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openssh/openssh-8.0p1-gssapi-keyex.patch
Dirk Mueller 0957114f91 Accepting request 960041 from home:hpjansson:openssh-tw 
- Version update to 8.9p1:
  = Security
  * sshd(8): fix an integer overflow in the user authentication path
    that, in conjunction with other logic errors, could have yielded
    unauthenticated access under difficult to exploit conditions.
    This situation is not exploitable because of independent checks in
    the privilege separation monitor. Privilege separation has been
    enabled by default in since openssh-3.2.2 (released in 2002) and
    has been mandatory since openssh-7.5 (released in 2017). Moreover,
    portable OpenSSH has used toolchain features available in most
    modern compilers to abort on signed integer overflow since
    openssh-6.5 (released in 2014).
    Thanks to Malcolm Stagg for finding and reporting this bug.
  = Potentially-incompatible changes
  * sshd(8), portable OpenSSH only: this release removes in-built
    support for MD5-hashed passwords. If you require these on your
    system then we recommend linking against libxcrypt or similar.
  * This release modifies the FIDO security key middleware interface
    and increments SSH_SK_VERSION_MAJOR.
  = New features
  * ssh(1), sshd(8), ssh-add(1), ssh-agent(1): add a system for
    restricting forwarding and use of keys added to ssh-agent(1)
    A detailed description of the feature is available at
    https://www.openssh.com/agent-restrict.html and the protocol
    extensions are documented in the PROTOCOL and PROTOCOL.agent
    files in the source release.
  * ssh(1), sshd(8): add the sntrup761x25519-sha512@openssh.com hybrid
    ECDH/x25519 + Streamlined NTRU Prime post-quantum KEX to the
    default KEXAlgorithms list (after the ECDH methods but before the
    prime-group DH ones). The next release of OpenSSH is likely to
    make this key exchange the default method.
  * ssh-keygen(1): when downloading resident keys from a FIDO token,
    pass back the user ID that was used when the key was created and
    append it to the filename the key is written to (if it is not the
    default). Avoids keys being clobbered if the user created multiple
    resident keys with the same application string but different user
    IDs.
  * ssh-keygen(1), ssh(1), ssh-agent(1): better handling for FIDO keys
    on tokens that provide user verification (UV) on the device itself,
    including biometric keys, avoiding unnecessary PIN prompts.
  * ssh-keygen(1): add "ssh-keygen -Y match-principals" operation to
    perform matching of principals names against an allowed signers
    file. To be used towards a TOFU model for SSH signatures in git.
  * ssh-add(1), ssh-agent(1): allow pin-required FIDO keys to be added
    to ssh-agent(1). $SSH_ASKPASS will be used to request the PIN at
    authentication time.
  * ssh-keygen(1): allow selection of hash at sshsig signing time
    (either sha512 (default) or sha256).
  * ssh(1), sshd(8): read network data directly to the packet input
    buffer instead of indirectly via a small stack buffer. Provides a
    modest performance improvement.
  * ssh(1), sshd(8): read data directly to the channel input buffer,
    providing a similar modest performance improvement.
  * ssh(1): extend the PubkeyAuthentication configuration directive to
    accept yes|no|unbound|host-bound to allow control over one of the
    protocol extensions used to implement agent-restricted keys.
  = Bugfixes
  * sshd(8): document that CASignatureAlgorithms, ExposeAuthInfo and
    PubkeyAuthOptions can be used in a Match block. PR277.
  * sshd(8): fix possible string truncation when constructing paths to
    .rhosts/.shosts files with very long user home directory names.
  * ssh-keysign(1): unbreak for KEX algorithms that use SHA384/512
    exchange hashes
  * ssh(1): don't put the TTY into raw mode when SessionType=none,
    avoids ^C being unable to kill such a session. bz3360
  * scp(1): fix some corner-case bugs in SFTP-mode handling of
    ~-prefixed paths.
  * ssh(1): unbreak hostbased auth using RSA keys. Allow ssh(1) to
    select RSA keys when only RSA/SHA2 signature algorithms are
    configured (this is the default case). Previously RSA keys were
    not being considered in the default case.
  * ssh-keysign(1): make ssh-keysign use the requested signature
    algorithm and not the default for the key type. Part of unbreaking
    hostbased auth for RSA/SHA2 keys.
  * ssh(1): stricter UpdateHostkey signature verification logic on
    the client- side. Require RSA/SHA2 signatures for RSA hostkeys
    except when RSA/SHA1 was explicitly negotiated during initial
    KEX; bz3375
  * ssh(1), sshd(8): fix signature algorithm selection logic for
    UpdateHostkeys on the server side. The previous code tried to
    prefer RSA/SHA2 for hostkey proofs of RSA keys, but missed some
    cases. This will use RSA/SHA2 signatures for RSA keys if the
    client proposed these algorithms in initial KEX. bz3375
  * All: convert all uses of select(2)/pselect(2) to poll(2)/ppoll(2).
    This includes the mainloops in ssh(1), ssh-agent(1), ssh-agent(1)
    and sftp-server(8), as well as the sshd(8) listen loop and all
    other FD read/writability checks. On platforms with missing or
    broken poll(2)/ppoll(2) syscalls a select(2)-based compat shim is
    available.
  * ssh-keygen(1): the "-Y find-principals" command was verifying key
    validity when using ca certs but not with simple key lifetimes
    within the allowed signers file.
  * ssh-keygen(1): make sshsig verify-time argument parsing optional
  * sshd(8): fix truncation in rhosts/shosts path construction.
  * ssh(1), ssh-agent(1): avoid xmalloc(0) for PKCS#11 keyid for ECDSA
    keys (we already did this for RSA keys). Avoids fatal errors for
    PKCS#11 libraries that return empty keyid, e.g. Microchip ATECC608B
    "cryptoauthlib"; bz#3364
  * ssh(1), ssh-agent(1): improve the testing of credentials against
    inserted FIDO: ask the token whether a particular key belongs to
    it in cases where the token supports on-token user-verification
    (e.g. biometrics) rather than just assuming that it will accept it.
    Will reduce spurious "Confirm user presence" notifications for key
    handles that relate to FIDO keys that are not currently inserted in at
    least some cases. bz3366
  * ssh(1), sshd(8): correct value for IPTOS_DSCP_LE. It needs to
    allow for the preceding two ECN bits. bz#3373
  * ssh-keygen(1): add missing -O option to usage() for the "-Y sign"
    option.
  * ssh-keygen(1): fix a NULL deref when using the find-principals
    function, when matching an allowed_signers line that contains a
    namespace restriction, but no restriction specified on the
    command-line
  * ssh-agent(1): fix memleak in process_extension(); oss-fuzz
    issue #42719
  * ssh(1): suppress "Connection to xxx closed" messages when LogLevel
    is set to "error" or above. bz3378
  * ssh(1), sshd(8): use correct zlib flags when inflate(3)-ing
    compressed packet data. bz3372
  * scp(1): when recursively transferring files in SFTP mode, create the
    destination directory if it doesn't already exist to match scp(1) in
    legacy RCP mode behaviour.
  * scp(1): many improvements in error message consistency between scp(1)
    in SFTP mode vs legacy RCP mode.
  * sshd(8): fix potential race in SIGTERM handling PR289
  * ssh(1), ssh(8): since DSA keys are deprecated, move them to the
    end of the default list of public keys so that they will be tried
    last. PR295
  * ssh-keygen(1): allow 'ssh-keygen -Y find-principals' to match
    wildcard principals in allowed_signers files
  = Portability
  * ssh(1), sshd(8): don't trust closefrom(2) on Linux. glibc's
    implementation does not work in a chroot when the kernel does not
    have close_range(2). It tries to read from /proc/self/fd and when
    that fails dies with an assertion of sorts. Instead, call
    close_range(2) directly from our compat code and fall back if
    that fails.  bz#3349,
  * OS X poll(2) is broken; use compat replacement. For character-
    special devices like /dev/null, Darwin's poll(2) returns POLLNVAL
    when polled with POLLIN. Apparently this is Apple bug 3710161 -
    not public but a websearch will find other OSS projects
    rediscovering it periodically since it was first identified in
    2005.
  * Correct handling of exceptfds/POLLPRI in our select(2)-based
    poll(2)/ppoll(2) compat implementation.
  * Cygwin: correct checking of mbstowcs() return value.
  * Add a basic SECURITY.md that refers people to the openssh.com
    website.
  * Enable additional compiler warnings and toolchain hardening flags,
    including -Wbitwise-instead-of-logical, -Wmisleading-indentation,
    -fzero-call-used-regs and -ftrivial-auto-var-init.
  * HP/UX. Use compat getline(3) on HP-UX 10.x, where the libc version
    is not reliable.
- Rebased patches:
  * openssh-7.7p1-ldap.patch
  * openssh-8.0p1-gssapi-keyex.patch
  * openssh-8.1p1-audit.patch
  * openssh-8.4p1-vendordir.patch
  * openssh-reenable-dh-group14-sha1-default.patch

OBS-URL: https://build.opensuse.org/request/show/960041
OBS-URL: https://build.opensuse.org/package/show/network/openssh?expand=0&rev=237
2022-03-08 07:49:22 +00:00

3916 lines
121 KiB
Diff
Raw Blame History

Index: openssh-8.9p1/Makefile.in
===================================================================
--- openssh-8.9p1.orig/Makefile.in
+++ openssh-8.9p1/Makefile.in
@@ -114,6 +114,7 @@ LIBSSH_OBJS=${LIBOPENSSH_OBJS} \
kex.o kexdh.o kexgex.o kexecdh.o kexc25519.o \
kexgexc.o kexgexs.o \
kexsntrup761x25519.o sntrup761.o kexgen.o \
+ kexgssc.o \
sftp-realpath.o platform-pledge.o platform-tracing.o platform-misc.o \
sshbuf-io.o
@@ -132,7 +133,7 @@ SSHDOBJS=sshd.o auth-rhosts.o auth-passw
auth-bsdauth.o auth2-hostbased.o auth2-kbdint.o \
auth2-none.o auth2-passwd.o auth2-pubkey.o \
monitor.o monitor_wrap.o auth-krb5.o \
- auth2-gss.o gss-serv.o gss-serv-krb5.o \
+ auth2-gss.o gss-serv.o gss-serv-krb5.o kexgsss.o \
loginrec.o auth-pam.o auth-shadow.o auth-sia.o \
srclimit.o sftp-server.o sftp-common.o \
sandbox-null.o sandbox-rlimit.o sandbox-systrace.o sandbox-darwin.o \
Index: openssh-8.9p1/auth.c
===================================================================
--- openssh-8.9p1.orig/auth.c
+++ openssh-8.9p1/auth.c
@@ -402,7 +402,8 @@ auth_root_allowed(struct ssh *ssh, const
case PERMIT_NO_PASSWD:
if (strcmp(method, "publickey") == 0 ||
strcmp(method, "hostbased") == 0 ||
- strcmp(method, "gssapi-with-mic") == 0)
+ strcmp(method, "gssapi-with-mic") == 0 ||
+ strcmp(method, "gssapi-keyex") == 0)
return 1;
break;
case PERMIT_FORCED_ONLY:
@@ -740,97 +741,6 @@ fakepw(void)
}
/*
- * Returns the remote DNS hostname as a string. The returned string must not
- * be freed. NB. this will usually trigger a DNS query the first time it is
- * called.
- * This function does additional checks on the hostname to mitigate some
- * attacks on based on conflation of hostnames and IP addresses.
- */
-
-static char *
-remote_hostname(struct ssh *ssh)
-{
- struct sockaddr_storage from;
- socklen_t fromlen;
- struct addrinfo hints, *ai, *aitop;
- char name[NI_MAXHOST], ntop2[NI_MAXHOST];
- const char *ntop = ssh_remote_ipaddr(ssh);
-
- /* Get IP address of client. */
- fromlen = sizeof(from);
- memset(&from, 0, sizeof(from));
- if (getpeername(ssh_packet_get_connection_in(ssh),
- (struct sockaddr *)&from, &fromlen) == -1) {
- debug("getpeername failed: %.100s", strerror(errno));
- return xstrdup(ntop);
- }
-
- ipv64_normalise_mapped(&from, &fromlen);
- if (from.ss_family == AF_INET6)
- fromlen = sizeof(struct sockaddr_in6);
-
- debug3("Trying to reverse map address %.100s.", ntop);
- /* Map the IP address to a host name. */
- if (getnameinfo((struct sockaddr *)&from, fromlen, name, sizeof(name),
- NULL, 0, NI_NAMEREQD) != 0) {
- /* Host name not found. Use ip address. */
- return xstrdup(ntop);
- }
-
- /*
- * if reverse lookup result looks like a numeric hostname,
- * someone is trying to trick us by PTR record like following:
- * 1.1.1.10.in-addr.arpa. IN PTR 2.3.4.5
- */
- memset(&hints, 0, sizeof(hints));
- hints.ai_socktype = SOCK_DGRAM; /*dummy*/
- hints.ai_flags = AI_NUMERICHOST;
- if (getaddrinfo(name, NULL, &hints, &ai) == 0) {
- logit("Nasty PTR record \"%s\" is set up for %s, ignoring",
- name, ntop);
- freeaddrinfo(ai);
- return xstrdup(ntop);
- }
-
- /* Names are stored in lowercase. */
- lowercase(name);
-
- /*
- * Map it back to an IP address and check that the given
- * address actually is an address of this host. This is
- * necessary because anyone with access to a name server can
- * define arbitrary names for an IP address. Mapping from
- * name to IP address can be trusted better (but can still be
- * fooled if the intruder has access to the name server of
- * the domain).
- */
- memset(&hints, 0, sizeof(hints));
- hints.ai_family = from.ss_family;
- hints.ai_socktype = SOCK_STREAM;
- if (getaddrinfo(name, NULL, &hints, &aitop) != 0) {
- logit("reverse mapping checking getaddrinfo for %.700s "
- "[%s] failed.", name, ntop);
- return xstrdup(ntop);
- }
- /* Look for the address from the list of addresses. */
- for (ai = aitop; ai; ai = ai->ai_next) {
- if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop2,
- sizeof(ntop2), NULL, 0, NI_NUMERICHOST) == 0 &&
- (strcmp(ntop, ntop2) == 0))
- break;
- }
- freeaddrinfo(aitop);
- /* If we reached the end of the list, the address was not there. */
- if (ai == NULL) {
- /* Address not found for the host name. */
- logit("Address %.100s maps to %.600s, but this does not "
- "map back to the address.", ntop, name);
- return xstrdup(ntop);
- }
- return xstrdup(name);
-}
-
-/*
* Return the canonical name of the host in the other side of the current
* connection. The host name is cached, so it is efficient to call this
* several times.
Index: openssh-8.9p1/auth2-gss.c
===================================================================
--- openssh-8.9p1.orig/auth2-gss.c
+++ openssh-8.9p1/auth2-gss.c
@@ -1,7 +1,7 @@
/* $OpenBSD: auth2-gss.c,v 1.33 2021/12/19 22:12:07 djm Exp $ */
/*
- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
+ * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -56,6 +56,48 @@ static int input_gssapi_exchange_complet
static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
/*
+ * The 'gssapi_keyex' userauth mechanism.
+ */
+static int
+userauth_gsskeyex(struct ssh *ssh)
+{
+ Authctxt *authctxt = ssh->authctxt;
+ int r, authenticated = 0;
+ struct sshbuf *b = NULL;
+ gss_buffer_desc mic, gssbuf;
+ u_char *p;
+ size_t len;
+
+ if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("%s: %s", __func__, ssh_err(r));
+
+ if ((b = sshbuf_new()) == NULL)
+ fatal("%s: sshbuf_new failed", __func__);
+
+ mic.value = p;
+ mic.length = len;
+
+ ssh_gssapi_buildmic(b, authctxt->user, authctxt->service,
+ "gssapi-keyex", ssh->kex->session_id);
+
+ if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
+ fatal("%s: sshbuf_mutable_ptr failed", __func__);
+ gssbuf.length = sshbuf_len(b);
+
+ /* gss_kex_context is NULL with privsep, so we can't check it here */
+ if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gss_kex_context,
+ &gssbuf, &mic))))
+ authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user,
+ authctxt->pw, 1));
+
+ sshbuf_free(b);
+ free(mic.value);
+
+ return (authenticated);
+}
+
+/*
* We only support those mechanisms that we know about (ie ones that we know
* how to check local user kuserok and the like)
*/
@@ -261,7 +303,8 @@ input_gssapi_exchange_complete(int type,
if ((r = sshpkt_get_end(ssh)) != 0)
fatal_fr(r, "parse packet");
- authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
+ authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user,
+ authctxt->pw, 1));
if ((!use_privsep || mm_is_monitor()) &&
(displayname = ssh_gssapi_displayname()) != NULL)
@@ -307,7 +350,8 @@ input_gssapi_mic(int type, u_int32_t ple
gssbuf.length = sshbuf_len(b);
if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gssctxt, &gssbuf, &mic))))
- authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
+ authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user,
+ authctxt->pw, 0));
else
logit("GSSAPI MIC check failed");
@@ -327,6 +371,12 @@ input_gssapi_mic(int type, u_int32_t ple
return 0;
}
+Authmethod method_gsskeyex = {
+ "gssapi-keyex",
+ userauth_gsskeyex,
+ &options.gss_authentication
+};
+
Authmethod method_gssapi = {
"gssapi-with-mic",
NULL,
Index: openssh-8.9p1/auth2.c
===================================================================
--- openssh-8.9p1.orig/auth2.c
+++ openssh-8.9p1/auth2.c
@@ -71,6 +71,7 @@ extern Authmethod method_passwd;
extern Authmethod method_kbdint;
extern Authmethod method_hostbased;
#ifdef GSSAPI
+extern Authmethod method_gsskeyex;
extern Authmethod method_gssapi;
#endif
@@ -78,6 +79,7 @@ Authmethod *authmethods[] = {
&method_none,
&method_pubkey,
#ifdef GSSAPI
+ &method_gsskeyex,
&method_gssapi,
#endif
&method_passwd,
Index: openssh-8.9p1/canohost.c
===================================================================
--- openssh-8.9p1.orig/canohost.c
+++ openssh-8.9p1/canohost.c
@@ -35,6 +35,99 @@
#include "canohost.h"
#include "misc.h"
+/*
+ * Returns the remote DNS hostname as a string. The returned string must not
+ * be freed. NB. this will usually trigger a DNS query the first time it is
+ * called.
+ * This function does additional checks on the hostname to mitigate some
+ * attacks on legacy rhosts-style authentication.
+ * XXX is RhostsRSAAuthentication vulnerable to these?
+ * XXX Can we remove these checks? (or if not, remove RhostsRSAAuthentication?)
+ */
+
+char *
+remote_hostname(struct ssh *ssh)
+{
+ struct sockaddr_storage from;
+ socklen_t fromlen;
+ struct addrinfo hints, *ai, *aitop;
+ char name[NI_MAXHOST], ntop2[NI_MAXHOST];
+ const char *ntop = ssh_remote_ipaddr(ssh);
+
+ /* Get IP address of client. */
+ fromlen = sizeof(from);
+ memset(&from, 0, sizeof(from));
+ if (getpeername(ssh_packet_get_connection_in(ssh),
+ (struct sockaddr *)&from, &fromlen) == -1) {
+ debug("getpeername failed: %.100s", strerror(errno));
+ return xstrdup(ntop);
+ }
+
+ ipv64_normalise_mapped(&from, &fromlen);
+ if (from.ss_family == AF_INET6)
+ fromlen = sizeof(struct sockaddr_in6);
+
+ debug3("Trying to reverse map address %.100s.", ntop);
+ /* Map the IP address to a host name. */
+ if (getnameinfo((struct sockaddr *)&from, fromlen, name, sizeof(name),
+ NULL, 0, NI_NAMEREQD) != 0) {
+ /* Host name not found. Use ip address. */
+ return xstrdup(ntop);
+ }
+
+ /*
+ * if reverse lookup result looks like a numeric hostname,
+ * someone is trying to trick us by PTR record like following:
+ * 1.1.1.10.in-addr.arpa. IN PTR 2.3.4.5
+ */
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_socktype = SOCK_DGRAM; /*dummy*/
+ hints.ai_flags = AI_NUMERICHOST;
+ if (getaddrinfo(name, NULL, &hints, &ai) == 0) {
+ logit("Nasty PTR record \"%s\" is set up for %s, ignoring",
+ name, ntop);
+ freeaddrinfo(ai);
+ return xstrdup(ntop);
+ }
+
+ /* Names are stored in lowercase. */
+ lowercase(name);
+
+ /*
+ * Map it back to an IP address and check that the given
+ * address actually is an address of this host. This is
+ * necessary because anyone with access to a name server can
+ * define arbitrary names for an IP address. Mapping from
+ * name to IP address can be trusted better (but can still be
+ * fooled if the intruder has access to the name server of
+ * the domain).
+ */
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = from.ss_family;
+ hints.ai_socktype = SOCK_STREAM;
+ if (getaddrinfo(name, NULL, &hints, &aitop) != 0) {
+ logit("reverse mapping checking getaddrinfo for %.700s "
+ "[%s] failed.", name, ntop);
+ return xstrdup(ntop);
+ }
+ /* Look for the address from the list of addresses. */
+ for (ai = aitop; ai; ai = ai->ai_next) {
+ if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop2,
+ sizeof(ntop2), NULL, 0, NI_NUMERICHOST) == 0 &&
+ (strcmp(ntop, ntop2) == 0))
+ break;
+ }
+ freeaddrinfo(aitop);
+ /* If we reached the end of the list, the address was not there. */
+ if (ai == NULL) {
+ /* Address not found for the host name. */
+ logit("Address %.100s maps to %.600s, but this does not "
+ "map back to the address.", ntop, name);
+ return xstrdup(ntop);
+ }
+ return xstrdup(name);
+}
+
void
ipv64_normalise_mapped(struct sockaddr_storage *addr, socklen_t *len)
{
Index: openssh-8.9p1/canohost.h
===================================================================
--- openssh-8.9p1.orig/canohost.h
+++ openssh-8.9p1/canohost.h
@@ -15,6 +15,9 @@
#ifndef _CANOHOST_H
#define _CANOHOST_H
+struct ssh;
+
+char *remote_hostname(struct ssh *);
char *get_peer_ipaddr(int);
int get_peer_port(int);
char *get_local_ipaddr(int);
Index: openssh-8.9p1/clientloop.c
===================================================================
--- openssh-8.9p1.orig/clientloop.c
+++ openssh-8.9p1/clientloop.c
@@ -118,6 +118,10 @@
/* Permitted RSA signature algorithms for UpdateHostkeys proofs */
#define HOSTKEY_PROOF_RSA_ALGS "rsa-sha2-512,rsa-sha2-256"
+#ifdef GSSAPI
+#include "ssh-gss.h"
+#endif
+
/* import options */
extern Options options;
@@ -1349,9 +1353,18 @@ client_loop(struct ssh *ssh, int have_pt
break;
/* Do channel operations unless rekeying in progress. */
- if (!ssh_packet_is_rekeying(ssh))
+ if (!ssh_packet_is_rekeying(ssh)) {
channel_after_poll(ssh, pfd, npfd_active);
+#ifdef GSSAPI
+ if (options.gss_renewal_rekey &&
+ ssh_gssapi_credentials_updated(NULL)) {
+ debug("credentials updated - forcing rekey");
+ need_rekeying = 1;
+ }
+#endif
+ }
+
/* Buffer input from the connection. */
if (conn_in_ready)
client_process_net_input(ssh);
Index: openssh-8.9p1/configure.ac
===================================================================
--- openssh-8.9p1.orig/configure.ac
+++ openssh-8.9p1/configure.ac
@@ -714,6 +714,30 @@ main() { if (NSVersionOfRunTimeLibrary("
[Use tunnel device compatibility to OpenBSD])
AC_DEFINE([SSH_TUN_PREPEND_AF], [1],
[Prepend the address family to IP tunnel traffic])
+ AC_MSG_CHECKING([if we have the Security Authorization Session API])
+ AC_TRY_COMPILE([#include <Security/AuthSession.h>],
+ [SessionCreate(0, 0);],
+ [ac_cv_use_security_session_api="yes"
+ AC_DEFINE([USE_SECURITY_SESSION_API], [1],
+ [platform has the Security Authorization Session API])
+ LIBS="$LIBS -framework Security"
+ AC_MSG_RESULT([yes])],
+ [ac_cv_use_security_session_api="no"
+ AC_MSG_RESULT([no])])
+ AC_MSG_CHECKING([if we have an in-memory credentials cache])
+ AC_TRY_COMPILE(
+ [#include <Kerberos/Kerberos.h>],
+ [cc_context_t c;
+ (void) cc_initialize (&c, 0, NULL, NULL);],
+ [AC_DEFINE([USE_CCAPI], [1],
+ [platform uses an in-memory credentials cache])
+ LIBS="$LIBS -framework Security"
+ AC_MSG_RESULT([yes])
+ if test "x$ac_cv_use_security_session_api" = "xno"; then
+ AC_MSG_ERROR([*** Need a security framework to use the credentials cache API ***])
+ fi],
+ [AC_MSG_RESULT([no])]
+ )
m4_pattern_allow([AU_IPv])
AC_CHECK_DECL([AU_IPv4], [],
AC_DEFINE([AU_IPv4], [0], [System only supports IPv4 audit records])
Index: openssh-8.9p1/gss-genr.c
===================================================================
--- openssh-8.9p1.orig/gss-genr.c
+++ openssh-8.9p1/gss-genr.c
@@ -1,7 +1,7 @@
/* $OpenBSD: gss-genr.c,v 1.28 2021/01/27 10:05:28 djm Exp $ */
/*
- * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -43,8 +43,34 @@
#include "log.h"
#include "ssh2.h"
+#include "cipher.h"
+#include "sshkey.h"
+#include "kex.h"
+#include "digest.h"
+#include "packet.h"
+
#include "ssh-gss.h"
+typedef struct {
+ char *encoded;
+ gss_OID oid;
+} ssh_gss_kex_mapping;
+
+/*
+ * XXX - It would be nice to find a more elegant way of handling the
+ * XXX passing of the key exchange context to the userauth routines
+ */
+
+Gssctxt *gss_kex_context = NULL;
+
+static ssh_gss_kex_mapping *gss_enc2oid = NULL;
+
+int
+ssh_gssapi_oid_table_ok(void)
+{
+ return (gss_enc2oid != NULL);
+}
+
/* sshbuf_get for gss_buffer_desc */
int
ssh_gssapi_get_buffer_desc(struct sshbuf *b, gss_buffer_desc *g)
@@ -60,6 +86,161 @@ ssh_gssapi_get_buffer_desc(struct sshbuf
return 0;
}
+/* sshpkt_get of gss_buffer_desc */
+int
+ssh_gssapi_sshpkt_get_buffer_desc(struct ssh *ssh, gss_buffer_desc *g)
+{
+ int r;
+ u_char *p;
+ size_t len;
+
+ if ((r = sshpkt_get_string(ssh, &p, &len)) != 0)
+ return r;
+ g->value = p;
+ g->length = len;
+ return 0;
+}
+
+/*
+ * Return a list of the gss-group1-sha1 mechanisms supported by this program
+ *
+ * We test mechanisms to ensure that we can use them, to avoid starting
+ * a key exchange with a bad mechanism
+ */
+
+char *
+ssh_gssapi_client_mechanisms(const char *host, const char *client,
+ const char *kex) {
+ gss_OID_set gss_supported = NULL;
+ OM_uint32 min_status;
+
+ if (GSS_ERROR(gss_indicate_mechs(&min_status, &gss_supported)))
+ return NULL;
+
+ return ssh_gssapi_kex_mechs(gss_supported, ssh_gssapi_check_mechanism,
+ host, client, kex);
+}
+
+char *
+ssh_gssapi_kex_mechs(gss_OID_set gss_supported, ssh_gssapi_check_fn *check,
+ const char *host, const char *client, const char *kex) {
+ struct sshbuf *buf = NULL;
+ size_t i;
+ int r, oidpos, enclen;
+ char *mechs, *encoded;
+ u_char digest[SSH_DIGEST_MAX_LENGTH];
+ char deroid[2];
+ struct ssh_digest_ctx *md = NULL;
+ char *s, *cp, *p;
+
+ if (gss_enc2oid != NULL) {
+ for (i = 0; gss_enc2oid[i].encoded != NULL; i++)
+ free(gss_enc2oid[i].encoded);
+ free(gss_enc2oid);
+ }
+
+ gss_enc2oid = xmalloc(sizeof(ssh_gss_kex_mapping) *
+ (gss_supported->count + 1));
+
+ if ((buf = sshbuf_new()) == NULL)
+ fatal("%s: sshbuf_new failed", __func__);
+
+ oidpos = 0;
+ s = cp = xstrdup(kex);
+ for (i = 0; i < gss_supported->count; i++) {
+ if (gss_supported->elements[i].length < 128 &&
+ (*check)(NULL, &(gss_supported->elements[i]), host, client)) {
+
+ deroid[0] = SSH_GSS_OIDTYPE;
+ deroid[1] = gss_supported->elements[i].length;
+
+ if ((md = ssh_digest_start(SSH_DIGEST_MD5)) == NULL ||
+ (r = ssh_digest_update(md, deroid, 2)) != 0 ||
+ (r = ssh_digest_update(md,
+ gss_supported->elements[i].elements,
+ gss_supported->elements[i].length)) != 0 ||
+ (r = ssh_digest_final(md, digest, sizeof(digest))) != 0)
+ fatal("%s: digest failed: %s", __func__,
+ ssh_err(r));
+ ssh_digest_free(md);
+ md = NULL;
+
+ encoded = xmalloc(ssh_digest_bytes(SSH_DIGEST_MD5)
+ * 2);
+ enclen = __b64_ntop(digest,
+ ssh_digest_bytes(SSH_DIGEST_MD5), encoded,
+ ssh_digest_bytes(SSH_DIGEST_MD5) * 2);
+
+ cp = strncpy(s, kex, strlen(kex));
+ for ((p = strsep(&cp, ",")); p && *p != '\0';
+ (p = strsep(&cp, ","))) {
+ if (sshbuf_len(buf) != 0 &&
+ (r = sshbuf_put_u8(buf, ',')) != 0)
+ fatal("%s: sshbuf_put_u8 error: %s",
+ __func__, ssh_err(r));
+ if ((r = sshbuf_put(buf, p, strlen(p))) != 0 ||
+ (r = sshbuf_put(buf, encoded, enclen)) != 0)
+ fatal("%s: sshbuf_put error: %s",
+ __func__, ssh_err(r));
+ }
+
+ gss_enc2oid[oidpos].oid = &(gss_supported->elements[i]);
+ gss_enc2oid[oidpos].encoded = encoded;
+ oidpos++;
+ }
+ }
+ free(s);
+ gss_enc2oid[oidpos].oid = NULL;
+ gss_enc2oid[oidpos].encoded = NULL;
+
+ if ((mechs = sshbuf_dup_string(buf)) == NULL)
+ fatal("%s: sshbuf_dup_string failed", __func__);
+
+ sshbuf_free(buf);
+
+ if (strlen(mechs) == 0) {
+ free(mechs);
+ mechs = NULL;
+ }
+
+ return (mechs);
+}
+
+gss_OID
+ssh_gssapi_id_kex(Gssctxt *ctx, char *name, int kex_type) {
+ int i = 0;
+
+#define SKIP_KEX_NAME(type) \
+ case type: \
+ if (strlen(name) < sizeof(type##_ID)) \
+ return GSS_C_NO_OID; \
+ name += sizeof(type##_ID) - 1; \
+ break;
+
+ switch (kex_type) {
+ SKIP_KEX_NAME(KEX_GSS_GRP1_SHA1)
+ SKIP_KEX_NAME(KEX_GSS_GRP14_SHA1)
+ SKIP_KEX_NAME(KEX_GSS_GRP14_SHA256)
+ SKIP_KEX_NAME(KEX_GSS_GRP16_SHA512)
+ SKIP_KEX_NAME(KEX_GSS_GEX_SHA1)
+ SKIP_KEX_NAME(KEX_GSS_NISTP256_SHA256)
+ SKIP_KEX_NAME(KEX_GSS_C25519_SHA256)
+ default:
+ return GSS_C_NO_OID;
+ }
+
+#undef SKIP_KEX_NAME
+
+ while (gss_enc2oid[i].encoded != NULL &&
+ strcmp(name, gss_enc2oid[i].encoded) != 0)
+ i++;
+
+ if (gss_enc2oid[i].oid != NULL && ctx != NULL)
+ ssh_gssapi_set_oid(ctx, gss_enc2oid[i].oid);
+
+ return gss_enc2oid[i].oid;
+}
+
/* Check that the OID in a data stream matches that in the context */
int
ssh_gssapi_check_oid(Gssctxt *ctx, void *data, size_t len)
@@ -216,7 +397,7 @@ ssh_gssapi_init_ctx(Gssctxt *ctx, int de
}
ctx->major = gss_init_sec_context(&ctx->minor,
- GSS_C_NO_CREDENTIAL, &ctx->context, ctx->name, ctx->oid,
+ ctx->client_creds, &ctx->context, ctx->name, ctx->oid,
GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG | deleg_flag,
0, NULL, recv_tok, NULL, send_tok, flags, NULL);
@@ -246,8 +427,42 @@ ssh_gssapi_import_name(Gssctxt *ctx, con
}
OM_uint32
+ssh_gssapi_client_identity(Gssctxt *ctx, const char *name)
+{
+ gss_buffer_desc gssbuf;
+ gss_name_t gssname;
+ OM_uint32 status;
+ gss_OID_set oidset;
+
+ gssbuf.value = (void *) name;
+ gssbuf.length = strlen(gssbuf.value);
+
+ gss_create_empty_oid_set(&status, &oidset);
+ gss_add_oid_set_member(&status, ctx->oid, &oidset);
+
+ ctx->major = gss_import_name(&ctx->minor, &gssbuf,
+ GSS_C_NT_USER_NAME, &gssname);
+
+ if (!ctx->major)
+ ctx->major = gss_acquire_cred(&ctx->minor,
+ gssname, 0, oidset, GSS_C_INITIATE,
+ &ctx->client_creds, NULL, NULL);
+
+ gss_release_name(&status, &gssname);
+ gss_release_oid_set(&status, &oidset);
+
+ if (ctx->major)
+ ssh_gssapi_error(ctx);
+
+ return(ctx->major);
+}
+
+OM_uint32
ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
{
+ if (ctx == NULL)
+ return -1;
+
if ((ctx->major = gss_get_mic(&ctx->minor, ctx->context,
GSS_C_QOP_DEFAULT, buffer, hash)))
ssh_gssapi_error(ctx);
@@ -255,6 +470,19 @@ ssh_gssapi_sign(Gssctxt *ctx, gss_buffer
return (ctx->major);
}
+/* Priviledged when used by server */
+OM_uint32
+ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
+{
+ if (ctx == NULL)
+ return -1;
+
+ ctx->major = gss_verify_mic(&ctx->minor, ctx->context,
+ gssbuf, gssmic, NULL);
+
+ return (ctx->major);
+}
+
void
ssh_gssapi_buildmic(struct sshbuf *b, const char *user, const char *service,
const char *context, const struct sshbuf *session_id)
@@ -271,11 +499,16 @@ ssh_gssapi_buildmic(struct sshbuf *b, co
}
int
-ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
+ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host,
+ const char *client)
{
gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
OM_uint32 major, minor;
gss_OID_desc spnego_oid = {6, (void *)"\x2B\x06\x01\x05\x05\x02"};
+ Gssctxt *intctx = NULL;
+
+ if (ctx == NULL)
+ ctx = &intctx;
/* RFC 4462 says we MUST NOT do SPNEGO */
if (oid->length == spnego_oid.length &&
@@ -285,6 +518,10 @@ ssh_gssapi_check_mechanism(Gssctxt **ctx
ssh_gssapi_build_ctx(ctx);
ssh_gssapi_set_oid(*ctx, oid);
major = ssh_gssapi_import_name(*ctx, host);
+
+ if (!GSS_ERROR(major) && client)
+ major = ssh_gssapi_client_identity(*ctx, client);
+
if (!GSS_ERROR(major)) {
major = ssh_gssapi_init_ctx(*ctx, 0, GSS_C_NO_BUFFER, &token,
NULL);
@@ -294,10 +531,66 @@ ssh_gssapi_check_mechanism(Gssctxt **ctx
GSS_C_NO_BUFFER);
}
- if (GSS_ERROR(major))
+ if (GSS_ERROR(major) || intctx != NULL)
ssh_gssapi_delete_ctx(ctx);
return (!GSS_ERROR(major));
}
+int
+ssh_gssapi_credentials_updated(Gssctxt *ctxt) {
+ static gss_name_t saved_name = GSS_C_NO_NAME;
+ static OM_uint32 saved_lifetime = 0;
+ static gss_OID saved_mech = GSS_C_NO_OID;
+ static gss_name_t name;
+ static OM_uint32 last_call = 0;
+ OM_uint32 lifetime, now, major, minor;
+ int equal;
+
+ now = time(NULL);
+
+ if (ctxt) {
+ debug("Rekey has happened - updating saved versions");
+
+ if (saved_name != GSS_C_NO_NAME)
+ gss_release_name(&minor, &saved_name);
+
+ major = gss_inquire_cred(&minor, GSS_C_NO_CREDENTIAL,
+ &saved_name, &saved_lifetime, NULL, NULL);
+
+ if (!GSS_ERROR(major)) {
+ saved_mech = ctxt->oid;
+ saved_lifetime+= now;
+ } else {
+ /* Handle the error */
+ }
+ return 0;
+ }
+
+ if (now - last_call < 10)
+ return 0;
+
+ last_call = now;
+
+ if (saved_mech == GSS_C_NO_OID)
+ return 0;
+
+ major = gss_inquire_cred(&minor, GSS_C_NO_CREDENTIAL,
+ &name, &lifetime, NULL, NULL);
+ if (major == GSS_S_CREDENTIALS_EXPIRED)
+ return 0;
+ else if (GSS_ERROR(major))
+ return 0;
+
+ major = gss_compare_name(&minor, saved_name, name, &equal);
+ gss_release_name(&minor, &name);
+ if (GSS_ERROR(major))
+ return 0;
+
+ if (equal && (saved_lifetime < lifetime + now - 10))
+ return 1;
+
+ return 0;
+}
+
#endif /* GSSAPI */
Index: openssh-8.9p1/gss-serv-krb5.c
===================================================================
--- openssh-8.9p1.orig/gss-serv-krb5.c
+++ openssh-8.9p1/gss-serv-krb5.c
@@ -1,7 +1,7 @@
/* $OpenBSD: gss-serv-krb5.c,v 1.9 2018/07/09 21:37:55 markus Exp $ */
/*
- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
+ * Copyright (c) 2001-2007 Simon Wilkinson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -120,7 +120,7 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
krb5_error_code problem;
krb5_principal princ;
OM_uint32 maj_status, min_status;
- int len;
+ const char *new_ccname, *new_cctype;
const char *errmsg;
if (client->creds == NULL) {
@@ -180,11 +180,26 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
return;
}
- client->store.filename = xstrdup(krb5_cc_get_name(krb_context, ccache));
+ new_cctype = krb5_cc_get_type(krb_context, ccache);
+ new_ccname = krb5_cc_get_name(krb_context, ccache);
+
client->store.envvar = "KRB5CCNAME";
- len = strlen(client->store.filename) + 6;
- client->store.envval = xmalloc(len);
- snprintf(client->store.envval, len, "FILE:%s", client->store.filename);
+#ifdef USE_CCAPI
+ xasprintf(&client->store.envval, "API:%s", new_ccname);
+ client->store.filename = NULL;
+#else
+ if (new_ccname[0] == ':')
+ new_ccname++;
+ xasprintf(&client->store.envval, "%s:%s", new_cctype, new_ccname);
+ if (strcmp(new_cctype, "DIR") == 0) {
+ char *p;
+ p = strrchr(client->store.envval, '/');
+ if (p)
+ *p = '\0';
+ }
+ if ((strcmp(new_cctype, "FILE") == 0) || (strcmp(new_cctype, "DIR") == 0))
+ client->store.filename = xstrdup(new_ccname);
+#endif
#ifdef USE_PAM
if (options.use_pam)
@@ -193,9 +208,76 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
krb5_cc_close(krb_context, ccache);
+ client->store.data = krb_context;
+
return;
}
+int
+ssh_gssapi_krb5_updatecreds(ssh_gssapi_ccache *store,
+ ssh_gssapi_client *client)
+{
+ krb5_ccache ccache = NULL;
+ krb5_principal principal = NULL;
+ char *name = NULL;
+ krb5_error_code problem;
+ OM_uint32 maj_status, min_status;
+
+ if ((problem = krb5_cc_resolve(krb_context, store->envval, &ccache))) {
+ logit("krb5_cc_resolve(): %.100s",
+ krb5_get_err_text(krb_context, problem));
+ return 0;
+ }
+
+ /* Find out who the principal in this cache is */
+ if ((problem = krb5_cc_get_principal(krb_context, ccache,
+ &principal))) {
+ logit("krb5_cc_get_principal(): %.100s",
+ krb5_get_err_text(krb_context, problem));
+ krb5_cc_close(krb_context, ccache);
+ return 0;
+ }
+
+ if ((problem = krb5_unparse_name(krb_context, principal, &name))) {
+ logit("krb5_unparse_name(): %.100s",
+ krb5_get_err_text(krb_context, problem));
+ krb5_free_principal(krb_context, principal);
+ krb5_cc_close(krb_context, ccache);
+ return 0;
+ }
+
+
+ if (strcmp(name,client->exportedname.value)!=0) {
+ debug("Name in local credentials cache differs. Not storing");
+ krb5_free_principal(krb_context, principal);
+ krb5_cc_close(krb_context, ccache);
+ krb5_free_unparsed_name(krb_context, name);
+ return 0;
+ }
+ krb5_free_unparsed_name(krb_context, name);
+
+ /* Name matches, so lets get on with it! */
+
+ if ((problem = krb5_cc_initialize(krb_context, ccache, principal))) {
+ logit("krb5_cc_initialize(): %.100s",
+ krb5_get_err_text(krb_context, problem));
+ krb5_free_principal(krb_context, principal);
+ krb5_cc_close(krb_context, ccache);
+ return 0;
+ }
+
+ krb5_free_principal(krb_context, principal);
+
+ if ((maj_status = gss_krb5_copy_ccache(&min_status, client->creds,
+ ccache))) {
+ logit("gss_krb5_copy_ccache() failed. Sorry!");
+ krb5_cc_close(krb_context, ccache);
+ return 0;
+ }
+
+ return 1;
+}
+
ssh_gssapi_mech gssapi_kerberos_mech = {
"toWM5Slw5Ew8Mqkay+al2g==",
"Kerberos",
@@ -203,7 +285,8 @@ ssh_gssapi_mech gssapi_kerberos_mech = {
NULL,
&ssh_gssapi_krb5_userok,
NULL,
- &ssh_gssapi_krb5_storecreds
+ &ssh_gssapi_krb5_storecreds,
+ &ssh_gssapi_krb5_updatecreds
};
#endif /* KRB5 */
Index: openssh-8.9p1/gss-serv.c
===================================================================
--- openssh-8.9p1.orig/gss-serv.c
+++ openssh-8.9p1/gss-serv.c
@@ -1,7 +1,7 @@
/* $OpenBSD: gss-serv.c,v 1.32 2020/03/13 03:17:07 djm Exp $ */
/*
- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -44,17 +44,19 @@
#include "session.h"
#include "misc.h"
#include "servconf.h"
+#include "uidswap.h"
#include "ssh-gss.h"
+#include "monitor_wrap.h"
extern ServerOptions options;
static ssh_gssapi_client gssapi_client =
- { GSS_C_EMPTY_BUFFER, GSS_C_EMPTY_BUFFER,
- GSS_C_NO_CREDENTIAL, NULL, {NULL, NULL, NULL, NULL}};
+ { GSS_C_EMPTY_BUFFER, GSS_C_EMPTY_BUFFER, GSS_C_NO_CREDENTIAL,
+ GSS_C_NO_NAME, NULL, {NULL, NULL, NULL, NULL, NULL}, 0, 0};
ssh_gssapi_mech gssapi_null_mech =
- { NULL, NULL, {0, NULL}, NULL, NULL, NULL, NULL};
+ { NULL, NULL, {0, NULL}, NULL, NULL, NULL, NULL, NULL};
#ifdef KRB5
extern ssh_gssapi_mech gssapi_kerberos_mech;
@@ -141,6 +143,29 @@ ssh_gssapi_server_ctx(Gssctxt **ctx, gss
}
/* Unprivileged */
+char *
+ssh_gssapi_server_mechanisms(void) {
+ if (supported_oids == NULL)
+ ssh_gssapi_prepare_supported_oids();
+ return (ssh_gssapi_kex_mechs(supported_oids,
+ &ssh_gssapi_server_check_mech, NULL, NULL,
+ options.gss_kex_algorithms));
+}
+
+/* Unprivileged */
+int
+ssh_gssapi_server_check_mech(Gssctxt **dum, gss_OID oid, const char *data,
+ const char *dummy) {
+ Gssctxt *ctx = NULL;
+ int res;
+
+ res = !GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctx, oid)));
+ ssh_gssapi_delete_ctx(&ctx);
+
+ return (res);
+}
+
+/* Unprivileged */
void
ssh_gssapi_supported_oids(gss_OID_set *oidset)
{
@@ -150,7 +175,9 @@ ssh_gssapi_supported_oids(gss_OID_set *o
gss_OID_set supported;
gss_create_empty_oid_set(&min_status, oidset);
- gss_indicate_mechs(&min_status, &supported);
+
+ if (GSS_ERROR(gss_indicate_mechs(&min_status, &supported)))
+ return;
while (supported_mechs[i]->name != NULL) {
if (GSS_ERROR(gss_test_oid_set_member(&min_status,
@@ -276,8 +303,48 @@ OM_uint32
ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
{
int i = 0;
+ int equal = 0;
+ gss_name_t new_name = GSS_C_NO_NAME;
+ gss_buffer_desc ename = GSS_C_EMPTY_BUFFER;
+
+ if (options.gss_store_rekey && client->used && ctx->client_creds) {
+ if (client->mech->oid.length != ctx->oid->length ||
+ (memcmp(client->mech->oid.elements,
+ ctx->oid->elements, ctx->oid->length) !=0)) {
+ debug("Rekeyed credentials have different mechanism");
+ return GSS_S_COMPLETE;
+ }
+
+ if ((ctx->major = gss_inquire_cred_by_mech(&ctx->minor,
+ ctx->client_creds, ctx->oid, &new_name,
+ NULL, NULL, NULL))) {
+ ssh_gssapi_error(ctx);
+ return (ctx->major);
+ }
+
+ ctx->major = gss_compare_name(&ctx->minor, client->name,
+ new_name, &equal);
+
+ if (GSS_ERROR(ctx->major)) {
+ ssh_gssapi_error(ctx);
+ return (ctx->major);
+ }
+
+ if (!equal) {
+ debug("Rekeyed credentials have different name");
+ return GSS_S_COMPLETE;
+ }
- gss_buffer_desc ename;
+ debug("Marking rekeyed credentials for export");
+
+ gss_release_name(&ctx->minor, &client->name);
+ gss_release_cred(&ctx->minor, &client->creds);
+ client->name = new_name;
+ client->creds = ctx->client_creds;
+ ctx->client_creds = GSS_C_NO_CREDENTIAL;
+ client->updated = 1;
+ return GSS_S_COMPLETE;
+ }
client->mech = NULL;
@@ -292,6 +359,13 @@ ssh_gssapi_getclient(Gssctxt *ctx, ssh_g
if (client->mech == NULL)
return GSS_S_FAILURE;
+ if (ctx->client_creds &&
+ (ctx->major = gss_inquire_cred_by_mech(&ctx->minor,
+ ctx->client_creds, ctx->oid, &client->name, NULL, NULL, NULL))) {
+ ssh_gssapi_error(ctx);
+ return (ctx->major);
+ }
+
if ((ctx->major = gss_display_name(&ctx->minor, ctx->client,
&client->displayname, NULL))) {
ssh_gssapi_error(ctx);
@@ -309,6 +383,8 @@ ssh_gssapi_getclient(Gssctxt *ctx, ssh_g
return (ctx->major);
}
+ gss_release_buffer(&ctx->minor, &ename);
+
/* We can't copy this structure, so we just move the pointer to it */
client->creds = ctx->client_creds;
ctx->client_creds = GSS_C_NO_CREDENTIAL;
@@ -319,11 +395,20 @@ ssh_gssapi_getclient(Gssctxt *ctx, ssh_g
void
ssh_gssapi_cleanup_creds(void)
{
- if (gssapi_client.store.filename != NULL) {
- /* Unlink probably isn't sufficient */
- debug("removing gssapi cred file\"%s\"",
- gssapi_client.store.filename);
- unlink(gssapi_client.store.filename);
+ krb5_ccache ccache = NULL;
+ krb5_error_code problem;
+
+ if (gssapi_client.store.data != NULL) {
+ if ((problem = krb5_cc_resolve(gssapi_client.store.data, gssapi_client.store.envval, &ccache))) {
+ debug("%s: krb5_cc_resolve(): %.100s", __func__,
+ krb5_get_err_text(gssapi_client.store.data, problem));
+ } else if ((problem = krb5_cc_destroy(gssapi_client.store.data, ccache))) {
+ debug("%s: krb5_cc_destroy(): %.100s", __func__,
+ krb5_get_err_text(gssapi_client.store.data, problem));
+ } else {
+ krb5_free_context(gssapi_client.store.data);
+ gssapi_client.store.data = NULL;
+ }
}
}
@@ -356,19 +441,23 @@ ssh_gssapi_do_child(char ***envp, u_int
/* Privileged */
int
-ssh_gssapi_userok(char *user)
+ssh_gssapi_userok(char *user, struct passwd *pw, int kex)
{
OM_uint32 lmin;
+ (void) kex; /* used in privilege separation */
+
if (gssapi_client.exportedname.length == 0 ||
gssapi_client.exportedname.value == NULL) {
debug("No suitable client data");
return 0;
}
if (gssapi_client.mech && gssapi_client.mech->userok)
- if ((*gssapi_client.mech->userok)(&gssapi_client, user))
+ if ((*gssapi_client.mech->userok)(&gssapi_client, user)) {
+ gssapi_client.used = 1;
+ gssapi_client.store.owner = pw;
return 1;
- else {
+ } else {
/* Destroy delegated credentials if userok fails */
gss_release_buffer(&lmin, &gssapi_client.displayname);
gss_release_buffer(&lmin, &gssapi_client.exportedname);
@@ -382,14 +471,90 @@ ssh_gssapi_userok(char *user)
return (0);
}
-/* Privileged */
-OM_uint32
-ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
+/* These bits are only used for rekeying. The unpriviledged child is running
+ * as the user, the monitor is root.
+ *
+ * In the child, we want to :
+ * *) Ask the monitor to store our credentials into the store we specify
+ * *) If it succeeds, maybe do a PAM update
+ */
+
+/* Stuff for PAM */
+
+#ifdef USE_PAM
+static int ssh_gssapi_simple_conv(int n, const struct pam_message **msg,
+ struct pam_response **resp, void *data)
{
- ctx->major = gss_verify_mic(&ctx->minor, ctx->context,
- gssbuf, gssmic, NULL);
+ return (PAM_CONV_ERR);
+}
+#endif
- return (ctx->major);
+void
+ssh_gssapi_rekey_creds(void) {
+ int ok;
+#ifdef USE_PAM
+ int ret;
+ pam_handle_t *pamh = NULL;
+ struct pam_conv pamconv = {ssh_gssapi_simple_conv, NULL};
+ char *envstr;
+#endif
+
+ if (gssapi_client.store.filename == NULL &&
+ gssapi_client.store.envval == NULL &&
+ gssapi_client.store.envvar == NULL)
+ return;
+
+ ok = PRIVSEP(ssh_gssapi_update_creds(&gssapi_client.store));
+
+ if (!ok)
+ return;
+
+ debug("Rekeyed credentials stored successfully");
+
+ /* Actually managing to play with the ssh pam stack from here will
+ * be next to impossible. In any case, we may want different options
+ * for rekeying. So, use our own :)
+ */
+#ifdef USE_PAM
+ if (!use_privsep) {
+ debug("Not even going to try and do PAM with privsep disabled");
+ return;
+ }
+
+ ret = pam_start("sshd-rekey", gssapi_client.store.owner->pw_name,
+ &pamconv, &pamh);
+ if (ret)
+ return;
+
+ xasprintf(&envstr, "%s=%s", gssapi_client.store.envvar,
+ gssapi_client.store.envval);
+
+ ret = pam_putenv(pamh, envstr);
+ if (!ret)
+ pam_setcred(pamh, PAM_REINITIALIZE_CRED);
+ pam_end(pamh, PAM_SUCCESS);
+#endif
+}
+
+int
+ssh_gssapi_update_creds(ssh_gssapi_ccache *store) {
+ int ok = 0;
+
+ /* Check we've got credentials to store */
+ if (!gssapi_client.updated)
+ return 0;
+
+ gssapi_client.updated = 0;
+
+ temporarily_use_uid(gssapi_client.store.owner);
+ if (gssapi_client.mech && gssapi_client.mech->updatecreds)
+ ok = (*gssapi_client.mech->updatecreds)(store, &gssapi_client);
+ else
+ debug("No update function for this mechanism");
+
+ restore_uid();
+
+ return ok;
}
/* Privileged */
Index: openssh-8.9p1/kex.c
===================================================================
--- openssh-8.9p1.orig/kex.c
+++ openssh-8.9p1/kex.c
@@ -57,11 +57,16 @@
#include "misc.h"
#include "dispatch.h"
#include "monitor.h"
+#include "xmalloc.h"
#include "ssherr.h"
#include "sshbuf.h"
#include "digest.h"
+#ifdef GSSAPI
+#include "ssh-gss.h"
+#endif
+
#include "fips.h"
/* prototype */
@@ -119,6 +124,19 @@ static const struct kexalg kexalgs_all[]
#endif /* HAVE_EVP_SHA256 || !WITH_OPENSSL */
{ NULL, 0, -1, -1},
};
+static const struct kexalg gss_kexalgs[] = {
+#ifdef GSSAPI
+ { KEX_GSS_GEX_SHA1_ID, KEX_GSS_GEX_SHA1, 0, SSH_DIGEST_SHA1 },
+ { KEX_GSS_GRP1_SHA1_ID, KEX_GSS_GRP1_SHA1, 0, SSH_DIGEST_SHA1 },
+ { KEX_GSS_GRP14_SHA1_ID, KEX_GSS_GRP14_SHA1, 0, SSH_DIGEST_SHA1 },
+ { KEX_GSS_GRP14_SHA256_ID, KEX_GSS_GRP14_SHA256, 0, SSH_DIGEST_SHA256 },
+ { KEX_GSS_GRP16_SHA512_ID, KEX_GSS_GRP16_SHA512, 0, SSH_DIGEST_SHA512 },
+ { KEX_GSS_NISTP256_SHA256_ID, KEX_GSS_NISTP256_SHA256,
+ NID_X9_62_prime256v1, SSH_DIGEST_SHA256 },
+ { KEX_GSS_C25519_SHA256_ID, KEX_GSS_C25519_SHA256, 0, SSH_DIGEST_SHA256 },
+#endif
+ { NULL, 0, -1, -1 },
+};
static const struct kexalg kexalgs_fips140_2[] = {
#ifdef WITH_OPENSSL
@@ -146,12 +164,12 @@ static const struct kexalg kexalgs_fips1
/* Returns array of macs available depending on selected FIPS mode */
static const struct kexalg *
-fips_select_kexalgs(void)
+fips_select_kexalgs(const struct kexalg *algs)
{
int fips = fips_mode();
switch (fips) {
case 0:
- return kexalgs_all;
+ return algs;
case 1:
return kexalgs_fips140_2;
default:
@@ -162,13 +180,13 @@ fips_select_kexalgs(void)
}
char *
-kex_alg_list(char sep)
+kex_alg_list_internal(char sep, const struct kexalg *algs)
{
char *ret = NULL, *tmp;
size_t nlen, rlen = 0;
const struct kexalg *k;
- for (k = fips_select_kexalgs(); k->name != NULL; k++) {
+ for (k = fips_select_kexalgs(algs); k->name != NULL; k++) {
if (ret != NULL)
ret[rlen++] = sep;
nlen = strlen(k->name);
@@ -183,15 +201,31 @@ kex_alg_list(char sep)
return ret;
}
+char *
+kex_alg_list(char sep)
+{
+ return kex_alg_list_internal(sep, kexalgs_all);
+}
+
+char *
+kex_gss_alg_list(char sep)
+{
+ return kex_alg_list_internal(sep, gss_kexalgs);
+}
+
static const struct kexalg *
kex_alg_by_name(const char *name)
{
const struct kexalg *k;
- for (k = fips_select_kexalgs(); k->name != NULL; k++) {
+ for (k = fips_select_kexalgs(kexalgs_all); k->name != NULL; k++) {
if (strcmp(k->name, name) == 0)
return k;
}
+ for (k = gss_kexalgs; k->name != NULL; k++) {
+ if (strncmp(k->name, name, strlen(k->name)) == 0)
+ return k;
+ }
return NULL;
}
@@ -363,6 +397,29 @@ kex_assemble_names(char **listp, const c
return r;
}
+/* Validate GSS KEX method name list */
+int
+kex_gss_names_valid(const char *names)
+{
+ char *s, *cp, *p;
+
+ if (names == NULL || *names == '\0')
+ return 0;
+ s = cp = xstrdup(names);
+ for ((p = strsep(&cp, ",")); p && *p != '\0';
+ (p = strsep(&cp, ","))) {
+ if (strncmp(p, "gss-", 4) != 0
+ || kex_alg_by_name(p) == NULL) {
+ error("Unsupported KEX algorithm \"%.100s\"", p);
+ free(s);
+ return 0;
+ }
+ }
+ debug3("gss kex names ok: [%s]", names);
+ free(s);
+ return 1;
+}
+
/* put algorithm proposal into buffer */
int
kex_prop2buf(struct sshbuf *b, char *proposal[PROPOSAL_MAX])
@@ -765,6 +822,9 @@ kex_free(struct kex *kex)
sshbuf_free(kex->session_id);
sshbuf_free(kex->initial_sig);
sshkey_free(kex->initial_hostkey);
+#ifdef GSSAPI
+ free(kex->gss_host);
+#endif /* GSSAPI */
free(kex->failed_choice);
free(kex->hostkey_alg);
free(kex->name);
Index: openssh-8.9p1/kex.h
===================================================================
--- openssh-8.9p1.orig/kex.h
+++ openssh-8.9p1/kex.h
@@ -102,6 +102,15 @@ enum kex_exchange {
KEX_ECDH_SHA2,
KEX_C25519_SHA256,
KEX_KEM_SNTRUP761X25519_SHA512,
+#ifdef GSSAPI
+ KEX_GSS_GRP1_SHA1,
+ KEX_GSS_GRP14_SHA1,
+ KEX_GSS_GRP14_SHA256,
+ KEX_GSS_GRP16_SHA512,
+ KEX_GSS_GEX_SHA1,
+ KEX_GSS_NISTP256_SHA256,
+ KEX_GSS_C25519_SHA256,
+#endif
KEX_MAX
};
@@ -159,6 +168,12 @@ struct kex {
u_int flags;
int hash_alg;
int ec_nid;
+#ifdef GSSAPI
+ int gss_deleg_creds;
+ int gss_trust_dns;
+ char *gss_host;
+ char *gss_client;
+#endif
char *failed_choice;
int (*verify_host_key)(struct sshkey *, struct ssh *);
struct sshkey *(*load_host_public_key)(int, int, struct ssh *);
@@ -180,8 +195,10 @@ struct kex {
int kex_names_valid(const char *);
char *kex_alg_list(char);
+char *kex_gss_alg_list(char);
char *kex_names_cat(const char *, const char *);
int kex_assemble_names(char **, const char *, const char *);
+int kex_gss_names_valid(const char *);
int kex_exchange_identification(struct ssh *, int, const char *);
@@ -209,6 +226,12 @@ int kexgex_client(struct ssh *);
int kexgex_server(struct ssh *);
int kex_gen_client(struct ssh *);
int kex_gen_server(struct ssh *);
+#ifdef GSSAPI
+int kexgssgex_client(struct ssh *);
+int kexgssgex_server(struct ssh *);
+int kexgss_client(struct ssh *);
+int kexgss_server(struct ssh *);
+#endif
int kex_dh_keypair(struct kex *);
int kex_dh_enc(struct kex *, const struct sshbuf *, struct sshbuf **,
@@ -241,6 +264,12 @@ int kexgex_hash(int, const struct sshbu
const BIGNUM *, const u_char *, size_t,
u_char *, size_t *);
+int kex_gen_hash(int hash_alg, const struct sshbuf *client_version,
+ const struct sshbuf *server_version, const struct sshbuf *client_kexinit,
+ const struct sshbuf *server_kexinit, const struct sshbuf *server_host_key_blob,
+ const struct sshbuf *client_pub, const struct sshbuf *server_pub,
+ const struct sshbuf *shared_secret, u_char *hash, size_t *hashlen);
+
void kexc25519_keygen(u_char key[CURVE25519_SIZE], u_char pub[CURVE25519_SIZE])
__attribute__((__bounded__(__minbytes__, 1, CURVE25519_SIZE)))
__attribute__((__bounded__(__minbytes__, 2, CURVE25519_SIZE)));
Index: openssh-8.9p1/kexdh.c
===================================================================
--- openssh-8.9p1.orig/kexdh.c
+++ openssh-8.9p1/kexdh.c
@@ -49,13 +49,23 @@ kex_dh_keygen(struct kex *kex)
{
switch (kex->kex_type) {
case KEX_DH_GRP1_SHA1:
+#ifdef GSSAPI
+ case KEX_GSS_GRP1_SHA1:
+#endif
kex->dh = dh_new_group1();
break;
case KEX_DH_GRP14_SHA1:
case KEX_DH_GRP14_SHA256:
+#ifdef GSSAPI
+ case KEX_GSS_GRP14_SHA1:
+ case KEX_GSS_GRP14_SHA256:
+#endif
kex->dh = dh_new_group14();
break;
case KEX_DH_GRP16_SHA512:
+#ifdef GSSAPI
+ case KEX_GSS_GRP16_SHA512:
+#endif
kex->dh = dh_new_group16();
break;
case KEX_DH_GRP18_SHA512:
Index: openssh-8.9p1/kexgen.c
===================================================================
--- openssh-8.9p1.orig/kexgen.c
+++ openssh-8.9p1/kexgen.c
@@ -44,7 +44,7 @@
static int input_kex_gen_init(int, u_int32_t, struct ssh *);
static int input_kex_gen_reply(int type, u_int32_t seq, struct ssh *ssh);
-static int
+int
kex_gen_hash(
int hash_alg,
const struct sshbuf *client_version,
Index: openssh-8.9p1/kexgssc.c
===================================================================
--- /dev/null
+++ openssh-8.9p1/kexgssc.c
@@ -0,0 +1,595 @@
+/*
+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#if defined(GSSAPI) && defined(WITH_OPENSSL)
+
+#include "includes.h"
+
+#include <openssl/crypto.h>
+#include <openssl/bn.h>
+
+#include <string.h>
+
+#include "xmalloc.h"
+#include "sshbuf.h"
+#include "ssh2.h"
+#include "sshkey.h"
+#include "cipher.h"
+#include "kex.h"
+#include "log.h"
+#include "packet.h"
+#include "dh.h"
+#include "digest.h"
+#include "ssherr.h"
+
+#include "ssh-gss.h"
+
+int
+kexgss_client(struct ssh *ssh)
+{
+ struct kex *kex = ssh->kex;
+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER,
+ recv_tok = GSS_C_EMPTY_BUFFER,
+ gssbuf, msg_tok = GSS_C_EMPTY_BUFFER, *token_ptr;
+ Gssctxt *ctxt;
+ OM_uint32 maj_status, min_status, ret_flags;
+ struct sshbuf *server_blob = NULL;
+ struct sshbuf *shared_secret = NULL;
+ struct sshbuf *server_host_key_blob = NULL;
+ struct sshbuf *empty = sshbuf_new();
+ u_char *msg;
+ int type = 0;
+ int first = 1;
+ u_char hash[SSH_DIGEST_MAX_LENGTH];
+ size_t hashlen;
+ u_char c;
+ int r;
+
+ /* Initialise our GSSAPI world */
+ ssh_gssapi_build_ctx(&ctxt);
+ if (ssh_gssapi_id_kex(ctxt, kex->name, kex->kex_type)
+ == GSS_C_NO_OID)
+ fatal("Couldn't identify host exchange");
+
+ if (ssh_gssapi_import_name(ctxt, kex->gss_host))
+ fatal("Couldn't import hostname");
+
+ if (kex->gss_client &&
+ ssh_gssapi_client_identity(ctxt, kex->gss_client))
+ fatal("Couldn't acquire client credentials");
+
+ /* Step 1 */
+ switch (kex->kex_type) {
+ case KEX_GSS_GRP1_SHA1:
+ case KEX_GSS_GRP14_SHA1:
+ case KEX_GSS_GRP14_SHA256:
+ case KEX_GSS_GRP16_SHA512:
+ r = kex_dh_keypair(kex);
+ break;
+ case KEX_GSS_NISTP256_SHA256:
+ r = kex_ecdh_keypair(kex);
+ break;
+ case KEX_GSS_C25519_SHA256:
+ r = kex_c25519_keypair(kex);
+ break;
+ default:
+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+ }
+ if (r != 0)
+ return r;
+
+ token_ptr = GSS_C_NO_BUFFER;
+
+ do {
+ debug("Calling gss_init_sec_context");
+
+ maj_status = ssh_gssapi_init_ctx(ctxt,
+ kex->gss_deleg_creds, token_ptr, &send_tok,
+ &ret_flags);
+
+ if (GSS_ERROR(maj_status)) {
+ /* XXX Useles code: Missing send? */
+ if (send_tok.length != 0) {
+ if ((r = sshpkt_start(ssh,
+ SSH2_MSG_KEXGSS_CONTINUE)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value,
+ send_tok.length)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ }
+ fatal("gss_init_context failed");
+ }
+
+ /* If we've got an old receive buffer get rid of it */
+ if (token_ptr != GSS_C_NO_BUFFER)
+ gss_release_buffer(&min_status, &recv_tok);
+
+ if (maj_status == GSS_S_COMPLETE) {
+ /* If mutual state flag is not true, kex fails */
+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
+ fatal("Mutual authentication failed");
+
+ /* If integ avail flag is not true kex fails */
+ if (!(ret_flags & GSS_C_INTEG_FLAG))
+ fatal("Integrity check failed");
+ }
+
+ /*
+ * If we have data to send, then the last message that we
+ * received cannot have been a 'complete'.
+ */
+ if (send_tok.length != 0) {
+ if (first) {
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_INIT)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value,
+ send_tok.length)) != 0 ||
+ (r = sshpkt_put_stringb(ssh, kex->client_pub)) != 0)
+ fatal("failed to construct packet: %s", ssh_err(r));
+ first = 0;
+ } else {
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_CONTINUE)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value,
+ send_tok.length)) != 0)
+ fatal("failed to construct packet: %s", ssh_err(r));
+ }
+ if ((r = sshpkt_send(ssh)) != 0)
+ fatal("failed to send packet: %s", ssh_err(r));
+ gss_release_buffer(&min_status, &send_tok);
+
+ /* If we've sent them data, they should reply */
+ do {
+ type = ssh_packet_read(ssh);
+ if (type == SSH2_MSG_KEXGSS_HOSTKEY) {
+ debug("Received KEXGSS_HOSTKEY");
+ if (server_host_key_blob)
+ fatal("Server host key received more than once");
+ if ((r = sshpkt_getb_froms(ssh, &server_host_key_blob)) != 0)
+ fatal("Failed to read server host key: %s", ssh_err(r));
+ }
+ } while (type == SSH2_MSG_KEXGSS_HOSTKEY);
+
+ switch (type) {
+ case SSH2_MSG_KEXGSS_CONTINUE:
+ debug("Received GSSAPI_CONTINUE");
+ if (maj_status == GSS_S_COMPLETE)
+ fatal("GSSAPI Continue received from server when complete");
+ if ((r = ssh_gssapi_sshpkt_get_buffer_desc(ssh,
+ &recv_tok)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("Failed to read token: %s", ssh_err(r));
+ break;
+ case SSH2_MSG_KEXGSS_COMPLETE:
+ debug("Received GSSAPI_COMPLETE");
+ if (msg_tok.value != NULL)
+ fatal("Received GSSAPI_COMPLETE twice?");
+ if ((r = sshpkt_getb_froms(ssh, &server_blob)) != 0 ||
+ (r = ssh_gssapi_sshpkt_get_buffer_desc(ssh,
+ &msg_tok)) != 0)
+ fatal("Failed to read message: %s", ssh_err(r));
+
+ /* Is there a token included? */
+ if ((r = sshpkt_get_u8(ssh, &c)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ if (c) {
+ if ((r = ssh_gssapi_sshpkt_get_buffer_desc(
+ ssh, &recv_tok)) != 0)
+ fatal("Failed to read token: %s", ssh_err(r));
+ /* If we're already complete - protocol error */
+ if (maj_status == GSS_S_COMPLETE)
+ sshpkt_disconnect(ssh, "Protocol error: received token when complete");
+ } else {
+ /* No token included */
+ if (maj_status != GSS_S_COMPLETE)
+ sshpkt_disconnect(ssh, "Protocol error: did not receive final token");
+ }
+ if ((r = sshpkt_get_end(ssh)) != 0) {
+ fatal("Expecting end of packet.");
+ }
+ break;
+ case SSH2_MSG_KEXGSS_ERROR:
+ debug("Received Error");
+ if ((r = sshpkt_get_u32(ssh, &maj_status)) != 0 ||
+ (r = sshpkt_get_u32(ssh, &min_status)) != 0 ||
+ (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
+ (r = sshpkt_get_string(ssh, NULL, NULL)) != 0 || /* lang tag */
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt_get failed: %s", ssh_err(r));
+ fatal("GSSAPI Error: \n%.400s", msg);
+ default:
+ sshpkt_disconnect(ssh, "Protocol error: didn't expect packet type %d",
+ type);
+ }
+ token_ptr = &recv_tok;
+ } else {
+ /* No data, and not complete */
+ if (maj_status != GSS_S_COMPLETE)
+ fatal("Not complete, and no token output");
+ }
+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
+
+ /*
+ * We _must_ have received a COMPLETE message in reply from the
+ * server, which will have set server_blob and msg_tok
+ */
+
+ if (type != SSH2_MSG_KEXGSS_COMPLETE)
+ fatal("Didn't receive a SSH2_MSG_KEXGSS_COMPLETE when I expected it");
+
+ /* compute shared secret */
+ switch (kex->kex_type) {
+ case KEX_GSS_GRP1_SHA1:
+ case KEX_GSS_GRP14_SHA1:
+ case KEX_GSS_GRP14_SHA256:
+ case KEX_GSS_GRP16_SHA512:
+ r = kex_dh_dec(kex, server_blob, &shared_secret);
+ break;
+ case KEX_GSS_C25519_SHA256:
+ if (sshbuf_ptr(server_blob)[sshbuf_len(server_blob)] & 0x80)
+ fatal("The received key has MSB of last octet set!");
+ r = kex_c25519_dec(kex, server_blob, &shared_secret);
+ break;
+ case KEX_GSS_NISTP256_SHA256:
+ if (sshbuf_len(server_blob) != 65)
+ fatal("The received NIST-P256 key did not match"
+ "expected length (expected 65, got %zu)", sshbuf_len(server_blob));
+
+ if (sshbuf_ptr(server_blob)[0] != POINT_CONVERSION_UNCOMPRESSED)
+ fatal("The received NIST-P256 key does not have first octet 0x04");
+
+ r = kex_ecdh_dec(kex, server_blob, &shared_secret);
+ break;
+ default:
+ r = SSH_ERR_INVALID_ARGUMENT;
+ break;
+ }
+ if (r != 0)
+ goto out;
+
+ hashlen = sizeof(hash);
+ if ((r = kex_gen_hash(
+ kex->hash_alg,
+ kex->client_version,
+ kex->server_version,
+ kex->my,
+ kex->peer,
+ (server_host_key_blob ? server_host_key_blob : empty),
+ kex->client_pub,
+ server_blob,
+ shared_secret,
+ hash, &hashlen)) != 0)
+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+
+ gssbuf.value = hash;
+ gssbuf.length = hashlen;
+
+ /* Verify that the hash matches the MIC we just got. */
+ if (GSS_ERROR(ssh_gssapi_checkmic(ctxt, &gssbuf, &msg_tok)))
+ sshpkt_disconnect(ssh, "Hash's MIC didn't verify");
+
+ gss_release_buffer(&min_status, &msg_tok);
+
+ if (kex->gss_deleg_creds)
+ ssh_gssapi_credentials_updated(ctxt);
+
+ if (gss_kex_context == NULL)
+ gss_kex_context = ctxt;
+ else
+ ssh_gssapi_delete_ctx(&ctxt);
+
+ if ((r = kex_derive_keys(ssh, hash, hashlen, shared_secret)) == 0)
+ r = kex_send_newkeys(ssh);
+
+out:
+ explicit_bzero(hash, sizeof(hash));
+ explicit_bzero(kex->c25519_client_key, sizeof(kex->c25519_client_key));
+ sshbuf_free(empty);
+ sshbuf_free(server_host_key_blob);
+ sshbuf_free(server_blob);
+ sshbuf_free(shared_secret);
+ sshbuf_free(kex->client_pub);
+ kex->client_pub = NULL;
+ return r;
+}
+
+int
+kexgssgex_client(struct ssh *ssh)
+{
+ struct kex *kex = ssh->kex;
+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER,
+ recv_tok = GSS_C_EMPTY_BUFFER, gssbuf,
+ msg_tok = GSS_C_EMPTY_BUFFER, *token_ptr;
+ Gssctxt *ctxt;
+ OM_uint32 maj_status, min_status, ret_flags;
+ struct sshbuf *shared_secret = NULL;
+ BIGNUM *p = NULL;
+ BIGNUM *g = NULL;
+ struct sshbuf *buf = NULL;
+ struct sshbuf *server_host_key_blob = NULL;
+ struct sshbuf *server_blob = NULL;
+ BIGNUM *dh_server_pub = NULL;
+ u_char *msg;
+ int type = 0;
+ int first = 1;
+ u_char hash[SSH_DIGEST_MAX_LENGTH];
+ size_t hashlen;
+ const BIGNUM *pub_key, *dh_p, *dh_g;
+ int nbits = 0, min = DH_GRP_MIN, max = DH_GRP_MAX;
+ struct sshbuf *empty = sshbuf_new();
+ u_char c;
+ int r;
+
+ /* Initialise our GSSAPI world */
+ ssh_gssapi_build_ctx(&ctxt);
+ if (ssh_gssapi_id_kex(ctxt, kex->name, kex->kex_type)
+ == GSS_C_NO_OID)
+ fatal("Couldn't identify host exchange");
+
+ if (ssh_gssapi_import_name(ctxt, kex->gss_host))
+ fatal("Couldn't import hostname");
+
+ if (kex->gss_client &&
+ ssh_gssapi_client_identity(ctxt, kex->gss_client))
+ fatal("Couldn't acquire client credentials");
+
+ debug("Doing group exchange");
+ nbits = dh_estimate(kex->dh_need * 8);
+
+ kex->min = DH_GRP_MIN;
+ kex->max = DH_GRP_MAX;
+ kex->nbits = nbits;
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_GROUPREQ)) != 0 ||
+ (r = sshpkt_put_u32(ssh, min)) != 0 ||
+ (r = sshpkt_put_u32(ssh, nbits)) != 0 ||
+ (r = sshpkt_put_u32(ssh, max)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ fatal("Failed to construct a packet: %s", ssh_err(r));
+
+ if ((r = ssh_packet_read_expect(ssh, SSH2_MSG_KEXGSS_GROUP)) != 0)
+ fatal("Error: %s", ssh_err(r));
+
+ if ((r = sshpkt_get_bignum2(ssh, &p)) != 0 ||
+ (r = sshpkt_get_bignum2(ssh, &g)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("shpkt_get_bignum2 failed: %s", ssh_err(r));
+
+ if (BN_num_bits(p) < min || BN_num_bits(p) > max)
+ fatal("GSSGRP_GEX group out of range: %d !< %d !< %d",
+ min, BN_num_bits(p), max);
+
+ if ((kex->dh = dh_new_group(g, p)) == NULL)
+ fatal("dn_new_group() failed");
+ p = g = NULL; /* belong to kex->dh now */
+
+ if ((r = dh_gen_key(kex->dh, kex->we_need * 8)) != 0)
+ goto out;
+ DH_get0_key(kex->dh, &pub_key, NULL);
+
+ token_ptr = GSS_C_NO_BUFFER;
+
+ do {
+ /* Step 2 - call GSS_Init_sec_context() */
+ debug("Calling gss_init_sec_context");
+
+ maj_status = ssh_gssapi_init_ctx(ctxt,
+ kex->gss_deleg_creds, token_ptr, &send_tok,
+ &ret_flags);
+
+ if (GSS_ERROR(maj_status)) {
+ /* XXX Useles code: Missing send? */
+ if (send_tok.length != 0) {
+ if ((r = sshpkt_start(ssh,
+ SSH2_MSG_KEXGSS_CONTINUE)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value,
+ send_tok.length)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ }
+ fatal("gss_init_context failed");
+ }
+
+ /* If we've got an old receive buffer get rid of it */
+ if (token_ptr != GSS_C_NO_BUFFER)
+ gss_release_buffer(&min_status, &recv_tok);
+
+ if (maj_status == GSS_S_COMPLETE) {
+ /* If mutual state flag is not true, kex fails */
+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
+ fatal("Mutual authentication failed");
+
+ /* If integ avail flag is not true kex fails */
+ if (!(ret_flags & GSS_C_INTEG_FLAG))
+ fatal("Integrity check failed");
+ }
+
+ /*
+ * If we have data to send, then the last message that we
+ * received cannot have been a 'complete'.
+ */
+ if (send_tok.length != 0) {
+ if (first) {
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_INIT)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value,
+ send_tok.length)) != 0 ||
+ (r = sshpkt_put_bignum2(ssh, pub_key)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ first = 0;
+ } else {
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_CONTINUE)) != 0 ||
+ (r = sshpkt_put_string(ssh,send_tok.value,
+ send_tok.length)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ }
+ if ((r = sshpkt_send(ssh)) != 0)
+ fatal("sshpkt_send failed: %s", ssh_err(r));
+ gss_release_buffer(&min_status, &send_tok);
+
+ /* If we've sent them data, they should reply */
+ do {
+ type = ssh_packet_read(ssh);
+ if (type == SSH2_MSG_KEXGSS_HOSTKEY) {
+ debug("Received KEXGSS_HOSTKEY");
+ if (server_host_key_blob)
+ fatal("Server host key received more than once");
+ if ((r = sshpkt_getb_froms(ssh, &server_host_key_blob)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ }
+ } while (type == SSH2_MSG_KEXGSS_HOSTKEY);
+
+ switch (type) {
+ case SSH2_MSG_KEXGSS_CONTINUE:
+ debug("Received GSSAPI_CONTINUE");
+ if (maj_status == GSS_S_COMPLETE)
+ fatal("GSSAPI Continue received from server when complete");
+ if ((r = ssh_gssapi_sshpkt_get_buffer_desc(ssh,
+ &recv_tok)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ break;
+ case SSH2_MSG_KEXGSS_COMPLETE:
+ debug("Received GSSAPI_COMPLETE");
+ if (msg_tok.value != NULL)
+ fatal("Received GSSAPI_COMPLETE twice?");
+ if ((r = sshpkt_getb_froms(ssh, &server_blob)) != 0 ||
+ (r = ssh_gssapi_sshpkt_get_buffer_desc(ssh,
+ &msg_tok)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+
+ /* Is there a token included? */
+ if ((r = sshpkt_get_u8(ssh, &c)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ if (c) {
+ if ((r = ssh_gssapi_sshpkt_get_buffer_desc(
+ ssh, &recv_tok)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ /* If we're already complete - protocol error */
+ if (maj_status == GSS_S_COMPLETE)
+ sshpkt_disconnect(ssh, "Protocol error: received token when complete");
+ } else {
+ /* No token included */
+ if (maj_status != GSS_S_COMPLETE)
+ sshpkt_disconnect(ssh, "Protocol error: did not receive final token");
+ }
+ break;
+ case SSH2_MSG_KEXGSS_ERROR:
+ debug("Received Error");
+ if ((r = sshpkt_get_u32(ssh, &maj_status)) != 0 ||
+ (r = sshpkt_get_u32(ssh, &min_status)) != 0 ||
+ (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
+ (r = sshpkt_get_string(ssh, NULL, NULL)) != 0 || /* lang tag */
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ fatal("GSSAPI Error: \n%.400s", msg);
+ default:
+ sshpkt_disconnect(ssh, "Protocol error: didn't expect packet type %d",
+ type);
+ }
+ token_ptr = &recv_tok;
+ } else {
+ /* No data, and not complete */
+ if (maj_status != GSS_S_COMPLETE)
+ fatal("Not complete, and no token output");
+ }
+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
+
+ /*
+ * We _must_ have received a COMPLETE message in reply from the
+ * server, which will have set dh_server_pub and msg_tok
+ */
+
+ if (type != SSH2_MSG_KEXGSS_COMPLETE)
+ fatal("Didn't receive a SSH2_MSG_KEXGSS_COMPLETE when I expected it");
+
+ /* 7. C verifies that the key Q_S is valid */
+ /* 8. C computes shared secret */
+ if ((buf = sshbuf_new()) == NULL ||
+ (r = sshbuf_put_stringb(buf, server_blob)) != 0 ||
+ (r = sshbuf_get_bignum2(buf, &dh_server_pub)) != 0)
+ goto out;
+ sshbuf_free(buf);
+
+ if ((shared_secret = sshbuf_new()) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+
+ if ((r = kex_dh_compute_key(kex, dh_server_pub, shared_secret)) != 0)
+ goto out;
+
+ DH_get0_pqg(kex->dh, &dh_p, NULL, &dh_g);
+ hashlen = sizeof(hash);
+ if ((r = kexgex_hash(
+ kex->hash_alg,
+ kex->client_version,
+ kex->server_version,
+ kex->my,
+ kex->peer,
+ (server_host_key_blob ? server_host_key_blob : empty),
+ kex->min, kex->nbits, kex->max,
+ dh_p, dh_g,
+ pub_key,
+ dh_server_pub,
+ sshbuf_ptr(shared_secret), sshbuf_len(shared_secret),
+ hash, &hashlen)) != 0)
+ fatal("Failed to calculate hash: %s", ssh_err(r));
+
+ gssbuf.value = hash;
+ gssbuf.length = hashlen;
+
+ /* Verify that the hash matches the MIC we just got. */
+ if (GSS_ERROR(ssh_gssapi_checkmic(ctxt, &gssbuf, &msg_tok)))
+ sshpkt_disconnect(ssh, "Hash's MIC didn't verify");
+
+ gss_release_buffer(&min_status, &msg_tok);
+
+ /* save session id */
+ if (kex->session_id == NULL) {
+ kex->session_id = sshbuf_new ();
+ if ((r = sshbuf_put(kex->session_id, hash, hashlen)) != 0)
+ goto out;
+ }
+
+ if (kex->gss_deleg_creds)
+ ssh_gssapi_credentials_updated(ctxt);
+
+ if (gss_kex_context == NULL)
+ gss_kex_context = ctxt;
+ else
+ ssh_gssapi_delete_ctx(&ctxt);
+
+ /* Finally derive the keys and send them */
+ if ((r = kex_derive_keys(ssh, hash, hashlen, shared_secret)) == 0)
+ r = kex_send_newkeys(ssh);
+out:
+ sshbuf_free(server_blob);
+ sshbuf_free(empty);
+ explicit_bzero(hash, sizeof(hash));
+ DH_free(kex->dh);
+ kex->dh = NULL;
+ BN_clear_free(dh_server_pub);
+ sshbuf_free(shared_secret);
+ sshbuf_free(server_host_key_blob);
+ return r;
+}
+#endif /* defined(GSSAPI) && defined(WITH_OPENSSL) */
Index: openssh-8.9p1/kexgsss.c
===================================================================
--- /dev/null
+++ openssh-8.9p1/kexgsss.c
@@ -0,0 +1,474 @@
+/*
+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#if defined(GSSAPI) && defined(WITH_OPENSSL)
+
+#include <string.h>
+
+#include <openssl/crypto.h>
+#include <openssl/bn.h>
+
+#include "xmalloc.h"
+#include "sshbuf.h"
+#include "ssh2.h"
+#include "sshkey.h"
+#include "cipher.h"
+#include "kex.h"
+#include "log.h"
+#include "packet.h"
+#include "dh.h"
+#include "ssh-gss.h"
+#include "monitor_wrap.h"
+#include "misc.h" /* servconf.h needs misc.h for struct ForwardOptions */
+#include "servconf.h"
+#include "ssh-gss.h"
+#include "digest.h"
+#include "ssherr.h"
+
+extern ServerOptions options;
+
+int
+kexgss_server(struct ssh *ssh)
+{
+ struct kex *kex = ssh->kex;
+ OM_uint32 maj_status, min_status;
+
+ /*
+ * Some GSSAPI implementations use the input value of ret_flags (an
+ * output variable) as a means of triggering mechanism specific
+ * features. Initializing it to zero avoids inadvertently
+ * activating this non-standard behaviour.
+ */
+
+ OM_uint32 ret_flags = 0;
+ gss_buffer_desc gssbuf, recv_tok, msg_tok;
+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
+ Gssctxt *ctxt = NULL;
+ struct sshbuf *shared_secret = NULL;
+ struct sshbuf *client_pubkey = NULL;
+ struct sshbuf *server_pubkey = NULL;
+ struct sshbuf *empty = sshbuf_new();
+ int type = 0;
+ gss_OID oid;
+ char *mechs;
+ u_char hash[SSH_DIGEST_MAX_LENGTH];
+ size_t hashlen;
+ int r;
+
+ /* Initialise GSSAPI */
+
+ /* If we're rekeying, privsep means that some of the private structures
+ * in the GSSAPI code are no longer available. This kludges them back
+ * into life
+ */
+ if (!ssh_gssapi_oid_table_ok()) {
+ mechs = ssh_gssapi_server_mechanisms();
+ free(mechs);
+ }
+
+ debug2("%s: Identifying %s", __func__, kex->name);
+ oid = ssh_gssapi_id_kex(NULL, kex->name, kex->kex_type);
+ if (oid == GSS_C_NO_OID)
+ fatal("Unknown gssapi mechanism");
+
+ debug2("%s: Acquiring credentials", __func__);
+
+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctxt, oid))))
+ fatal("Unable to acquire credentials for the server");
+
+ do {
+ debug("Wait SSH2_MSG_KEXGSS_INIT");
+ type = ssh_packet_read(ssh);
+ switch(type) {
+ case SSH2_MSG_KEXGSS_INIT:
+ if (client_pubkey != NULL)
+ fatal("Received KEXGSS_INIT after initialising");
+ if ((r = ssh_gssapi_sshpkt_get_buffer_desc(ssh,
+ &recv_tok)) != 0 ||
+ (r = sshpkt_getb_froms(ssh, &client_pubkey)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+
+ switch (kex->kex_type) {
+ case KEX_GSS_GRP1_SHA1:
+ case KEX_GSS_GRP14_SHA1:
+ case KEX_GSS_GRP14_SHA256:
+ case KEX_GSS_GRP16_SHA512:
+ r = kex_dh_enc(kex, client_pubkey, &server_pubkey,
+ &shared_secret);
+ break;
+ case KEX_GSS_NISTP256_SHA256:
+ r = kex_ecdh_enc(kex, client_pubkey, &server_pubkey,
+ &shared_secret);
+ break;
+ case KEX_GSS_C25519_SHA256:
+ r = kex_c25519_enc(kex, client_pubkey, &server_pubkey,
+ &shared_secret);
+ break;
+ default:
+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+ }
+ if (r != 0)
+ goto out;
+
+ /* Send SSH_MSG_KEXGSS_HOSTKEY here, if we want */
+ break;
+ case SSH2_MSG_KEXGSS_CONTINUE:
+ if ((r = ssh_gssapi_sshpkt_get_buffer_desc(ssh,
+ &recv_tok)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ break;
+ default:
+ sshpkt_disconnect(ssh,
+ "Protocol error: didn't expect packet type %d",
+ type);
+ }
+
+ maj_status = PRIVSEP(ssh_gssapi_accept_ctx(ctxt, &recv_tok,
+ &send_tok, &ret_flags));
+
+ gss_release_buffer(&min_status, &recv_tok);
+
+ if (maj_status != GSS_S_COMPLETE && send_tok.length == 0)
+ fatal("Zero length token output when incomplete");
+
+ if (client_pubkey == NULL)
+ fatal("No client public key");
+
+ if (maj_status & GSS_S_CONTINUE_NEEDED) {
+ debug("Sending GSSAPI_CONTINUE");
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_CONTINUE)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value, send_tok.length)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ gss_release_buffer(&min_status, &send_tok);
+ }
+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
+
+ if (GSS_ERROR(maj_status)) {
+ if (send_tok.length > 0) {
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_CONTINUE)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value, send_tok.length)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ }
+ fatal("accept_ctx died");
+ }
+
+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
+ fatal("Mutual Authentication flag wasn't set");
+
+ if (!(ret_flags & GSS_C_INTEG_FLAG))
+ fatal("Integrity flag wasn't set");
+
+ hashlen = sizeof(hash);
+ if ((r = kex_gen_hash(
+ kex->hash_alg,
+ kex->client_version,
+ kex->server_version,
+ kex->peer,
+ kex->my,
+ empty,
+ client_pubkey,
+ server_pubkey,
+ shared_secret,
+ hash, &hashlen)) != 0)
+ goto out;
+
+ gssbuf.value = hash;
+ gssbuf.length = hashlen;
+
+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_sign(ctxt, &gssbuf, &msg_tok))))
+ fatal("Couldn't get MIC");
+
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_COMPLETE)) != 0 ||
+ (r = sshpkt_put_stringb(ssh, server_pubkey)) != 0 ||
+ (r = sshpkt_put_string(ssh, msg_tok.value, msg_tok.length)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+
+ if (send_tok.length != 0) {
+ if ((r = sshpkt_put_u8(ssh, 1)) != 0 || /* true */
+ (r = sshpkt_put_string(ssh, send_tok.value, send_tok.length)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ } else {
+ if ((r = sshpkt_put_u8(ssh, 0)) != 0) /* false */
+ fatal("sshpkt failed: %s", ssh_err(r));
+ }
+ if ((r = sshpkt_send(ssh)) != 0)
+ fatal("sshpkt_send failed: %s", ssh_err(r));
+
+ gss_release_buffer(&min_status, &send_tok);
+ gss_release_buffer(&min_status, &msg_tok);
+
+ if (gss_kex_context == NULL)
+ gss_kex_context = ctxt;
+ else
+ ssh_gssapi_delete_ctx(&ctxt);
+
+ if ((r = kex_derive_keys(ssh, hash, hashlen, shared_secret)) == 0)
+ r = kex_send_newkeys(ssh);
+
+ /* If this was a rekey, then save out any delegated credentials we
+ * just exchanged. */
+ if (options.gss_store_rekey)
+ ssh_gssapi_rekey_creds();
+out:
+ sshbuf_free(empty);
+ explicit_bzero(hash, sizeof(hash));
+ sshbuf_free(shared_secret);
+ sshbuf_free(client_pubkey);
+ sshbuf_free(server_pubkey);
+ return r;
+}
+
+int
+kexgssgex_server(struct ssh *ssh)
+{
+ struct kex *kex = ssh->kex;
+ OM_uint32 maj_status, min_status;
+
+ /*
+ * Some GSSAPI implementations use the input value of ret_flags (an
+ * output variable) as a means of triggering mechanism specific
+ * features. Initializing it to zero avoids inadvertently
+ * activating this non-standard behaviour.
+ */
+
+ OM_uint32 ret_flags = 0;
+ gss_buffer_desc gssbuf, recv_tok, msg_tok;
+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
+ Gssctxt *ctxt = NULL;
+ struct sshbuf *shared_secret = NULL;
+ int type = 0;
+ gss_OID oid;
+ char *mechs;
+ u_char hash[SSH_DIGEST_MAX_LENGTH];
+ size_t hashlen;
+ BIGNUM *dh_client_pub = NULL;
+ const BIGNUM *pub_key, *dh_p, *dh_g;
+ int min = -1, max = -1, nbits = -1;
+ int cmin = -1, cmax = -1; /* client proposal */
+ struct sshbuf *empty = sshbuf_new();
+ int r;
+
+ /* Initialise GSSAPI */
+
+ /* If we're rekeying, privsep means that some of the private structures
+ * in the GSSAPI code are no longer available. This kludges them back
+ * into life
+ */
+ if (!ssh_gssapi_oid_table_ok())
+ if ((mechs = ssh_gssapi_server_mechanisms()))
+ free(mechs);
+
+ debug2("%s: Identifying %s", __func__, kex->name);
+ oid = ssh_gssapi_id_kex(NULL, kex->name, kex->kex_type);
+ if (oid == GSS_C_NO_OID)
+ fatal("Unknown gssapi mechanism");
+
+ debug2("%s: Acquiring credentials", __func__);
+
+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctxt, oid))))
+ fatal("Unable to acquire credentials for the server");
+
+ /* 5. S generates an ephemeral key pair (do the allocations early) */
+ debug("Doing group exchange");
+ ssh_packet_read_expect(ssh, SSH2_MSG_KEXGSS_GROUPREQ);
+ /* store client proposal to provide valid signature */
+ if ((r = sshpkt_get_u32(ssh, &cmin)) != 0 ||
+ (r = sshpkt_get_u32(ssh, &nbits)) != 0 ||
+ (r = sshpkt_get_u32(ssh, &cmax)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ kex->nbits = nbits;
+ kex->min = cmin;
+ kex->max = cmax;
+ min = MAX(DH_GRP_MIN, cmin);
+ max = MIN(DH_GRP_MAX, cmax);
+ nbits = MAXIMUM(DH_GRP_MIN, nbits);
+ nbits = MINIMUM(DH_GRP_MAX, nbits);
+ if (max < min || nbits < min || max < nbits)
+ fatal("GSS_GEX, bad parameters: %d !< %d !< %d",
+ min, nbits, max);
+ kex->dh = PRIVSEP(choose_dh(min, nbits, max));
+ if (kex->dh == NULL) {
+ sshpkt_disconnect(ssh, "Protocol error: no matching group found");
+ fatal("Protocol error: no matching group found");
+ }
+
+ DH_get0_pqg(kex->dh, &dh_p, NULL, &dh_g);
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_GROUP)) != 0 ||
+ (r = sshpkt_put_bignum2(ssh, dh_p)) != 0 ||
+ (r = sshpkt_put_bignum2(ssh, dh_g)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+
+ if ((r = ssh_packet_write_wait(ssh)) != 0)
+ fatal("ssh_packet_write_wait: %s", ssh_err(r));
+
+ /* Compute our exchange value in parallel with the client */
+ if ((r = dh_gen_key(kex->dh, kex->we_need * 8)) != 0)
+ goto out;
+
+ do {
+ debug("Wait SSH2_MSG_GSSAPI_INIT");
+ type = ssh_packet_read(ssh);
+ switch(type) {
+ case SSH2_MSG_KEXGSS_INIT:
+ if (dh_client_pub != NULL)
+ fatal("Received KEXGSS_INIT after initialising");
+ if ((r = ssh_gssapi_sshpkt_get_buffer_desc(ssh,
+ &recv_tok)) != 0 ||
+ (r = sshpkt_get_bignum2(ssh, &dh_client_pub)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+
+ /* Send SSH_MSG_KEXGSS_HOSTKEY here, if we want */
+ break;
+ case SSH2_MSG_KEXGSS_CONTINUE:
+ if ((r = ssh_gssapi_sshpkt_get_buffer_desc(ssh,
+ &recv_tok)) != 0 ||
+ (r = sshpkt_get_end(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ break;
+ default:
+ sshpkt_disconnect(ssh,
+ "Protocol error: didn't expect packet type %d",
+ type);
+ }
+
+ maj_status = PRIVSEP(ssh_gssapi_accept_ctx(ctxt, &recv_tok,
+ &send_tok, &ret_flags));
+
+ gss_release_buffer(&min_status, &recv_tok);
+
+ if (maj_status != GSS_S_COMPLETE && send_tok.length == 0)
+ fatal("Zero length token output when incomplete");
+
+ if (dh_client_pub == NULL)
+ fatal("No client public key");
+
+ if (maj_status & GSS_S_CONTINUE_NEEDED) {
+ debug("Sending GSSAPI_CONTINUE");
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_CONTINUE)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value, send_tok.length)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ gss_release_buffer(&min_status, &send_tok);
+ }
+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
+
+ if (GSS_ERROR(maj_status)) {
+ if (send_tok.length > 0) {
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_CONTINUE)) != 0 ||
+ (r = sshpkt_put_string(ssh, send_tok.value, send_tok.length)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ }
+ fatal("accept_ctx died");
+ }
+
+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
+ fatal("Mutual Authentication flag wasn't set");
+
+ if (!(ret_flags & GSS_C_INTEG_FLAG))
+ fatal("Integrity flag wasn't set");
+
+ /* calculate shared secret */
+ if ((shared_secret = sshbuf_new()) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ if ((r = kex_dh_compute_key(kex, dh_client_pub, shared_secret)) != 0)
+ goto out;
+
+ DH_get0_key(kex->dh, &pub_key, NULL);
+ DH_get0_pqg(kex->dh, &dh_p, NULL, &dh_g);
+ hashlen = sizeof(hash);
+ if ((r = kexgex_hash(
+ kex->hash_alg,
+ kex->client_version,
+ kex->server_version,
+ kex->peer,
+ kex->my,
+ empty,
+ cmin, nbits, cmax,
+ dh_p, dh_g,
+ dh_client_pub,
+ pub_key,
+ sshbuf_ptr(shared_secret), sshbuf_len(shared_secret),
+ hash, &hashlen)) != 0)
+ fatal("kexgex_hash failed: %s", ssh_err(r));
+
+ gssbuf.value = hash;
+ gssbuf.length = hashlen;
+
+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_sign(ctxt, &gssbuf, &msg_tok))))
+ fatal("Couldn't get MIC");
+
+ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXGSS_COMPLETE)) != 0 ||
+ (r = sshpkt_put_bignum2(ssh, pub_key)) != 0 ||
+ (r = sshpkt_put_string(ssh, msg_tok.value, msg_tok.length)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+
+ if (send_tok.length != 0) {
+ if ((r = sshpkt_put_u8(ssh, 1)) != 0 || /* true */
+ (r = sshpkt_put_string(ssh, send_tok.value, send_tok.length)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+ } else {
+ if ((r = sshpkt_put_u8(ssh, 0)) != 0) /* false */
+ fatal("sshpkt failed: %s", ssh_err(r));
+ }
+ if ((r = sshpkt_send(ssh)) != 0)
+ fatal("sshpkt failed: %s", ssh_err(r));
+
+ gss_release_buffer(&min_status, &send_tok);
+ gss_release_buffer(&min_status, &msg_tok);
+
+ if (gss_kex_context == NULL)
+ gss_kex_context = ctxt;
+ else
+ ssh_gssapi_delete_ctx(&ctxt);
+
+ /* Finally derive the keys and send them */
+ if ((r = kex_derive_keys(ssh, hash, hashlen, shared_secret)) == 0)
+ r = kex_send_newkeys(ssh);
+
+ /* If this was a rekey, then save out any delegated credentials we
+ * just exchanged. */
+ if (options.gss_store_rekey)
+ ssh_gssapi_rekey_creds();
+out:
+ sshbuf_free(empty);
+ explicit_bzero(hash, sizeof(hash));
+ DH_free(kex->dh);
+ kex->dh = NULL;
+ BN_clear_free(dh_client_pub);
+ sshbuf_free(shared_secret);
+ return r;
+}
+#endif /* defined(GSSAPI) && defined(WITH_OPENSSL) */
Index: openssh-8.9p1/monitor.c
===================================================================
--- openssh-8.9p1.orig/monitor.c
+++ openssh-8.9p1/monitor.c
@@ -145,6 +145,8 @@ int mm_answer_gss_setup_ctx(struct ssh *
int mm_answer_gss_accept_ctx(struct ssh *, int, struct sshbuf *);
int mm_answer_gss_userok(struct ssh *, int, struct sshbuf *);
int mm_answer_gss_checkmic(struct ssh *, int, struct sshbuf *);
+int mm_answer_gss_sign(struct ssh*, int, struct sshbuf *);
+int mm_answer_gss_updatecreds(struct ssh*, int, struct sshbuf *);
#endif
#ifdef SSH_AUDIT_EVENTS
@@ -217,11 +219,18 @@ struct mon_table mon_dispatch_proto20[]
{MONITOR_REQ_GSSSTEP, 0, mm_answer_gss_accept_ctx},
{MONITOR_REQ_GSSUSEROK, MON_ONCE|MON_AUTHDECIDE, mm_answer_gss_userok},
{MONITOR_REQ_GSSCHECKMIC, MON_ONCE, mm_answer_gss_checkmic},
+ {MONITOR_REQ_GSSSIGN, MON_ONCE, mm_answer_gss_sign},
#endif
{0, 0, NULL}
};
struct mon_table mon_dispatch_postauth20[] = {
+#ifdef GSSAPI
+ {MONITOR_REQ_GSSSETUP, 0, mm_answer_gss_setup_ctx},
+ {MONITOR_REQ_GSSSTEP, 0, mm_answer_gss_accept_ctx},
+ {MONITOR_REQ_GSSSIGN, 0, mm_answer_gss_sign},
+ {MONITOR_REQ_GSSUPCREDS, 0, mm_answer_gss_updatecreds},
+#endif
#ifdef WITH_OPENSSL
{MONITOR_REQ_MODULI, 0, mm_answer_moduli},
#endif
@@ -290,6 +299,10 @@ monitor_child_preauth(struct ssh *ssh, s
/* Permit requests for moduli and signatures */
monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
+#ifdef GSSAPI
+ /* and for the GSSAPI key exchange */
+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSETUP, 1);
+#endif
/* The first few requests do not require asynchronous access */
while (!authenticated) {
@@ -401,6 +414,10 @@ monitor_child_postauth(struct ssh *ssh,
monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
+#ifdef GSSAPI
+ /* and for the GSSAPI key exchange */
+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSETUP, 1);
+#endif
if (auth_opts->permit_pty_flag) {
monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
@@ -1747,6 +1764,17 @@ monitor_apply_keystate(struct ssh *ssh,
# ifdef OPENSSL_HAS_ECC
kex->kex[KEX_ECDH_SHA2] = kex_gen_server;
# endif
+# ifdef GSSAPI
+ if (options.gss_keyex) {
+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server;
+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_server;
+ kex->kex[KEX_GSS_GRP14_SHA256] = kexgss_server;
+ kex->kex[KEX_GSS_GRP16_SHA512] = kexgss_server;
+ kex->kex[KEX_GSS_GEX_SHA1] = kexgssgex_server;
+ kex->kex[KEX_GSS_NISTP256_SHA256] = kexgss_server;
+ kex->kex[KEX_GSS_C25519_SHA256] = kexgss_server;
+ }
+# endif
#endif /* WITH_OPENSSL */
kex->kex[KEX_C25519_SHA256] = kex_gen_server;
kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_server;
@@ -1839,8 +1867,8 @@ mm_answer_gss_setup_ctx(struct ssh *ssh,
u_char *p;
int r;
- if (!options.gss_authentication)
- fatal_f("GSSAPI authentication not enabled");
+ if (!options.gss_authentication && !options.gss_keyex)
+ fatal_f("GSSAPI not enabled");
if ((r = sshbuf_get_string(m, &p, &len)) != 0)
fatal_fr(r, "parse");
@@ -1872,8 +1900,8 @@ mm_answer_gss_accept_ctx(struct ssh *ssh
OM_uint32 flags = 0; /* GSI needs this */
int r;
- if (!options.gss_authentication)
- fatal_f("GSSAPI authentication not enabled");
+ if (!options.gss_authentication && !options.gss_keyex)
+ fatal_f("GSSAPI not enabled");
if ((r = ssh_gssapi_get_buffer_desc(m, &in)) != 0)
fatal_fr(r, "ssh_gssapi_get_buffer_desc");
@@ -1893,6 +1921,7 @@ mm_answer_gss_accept_ctx(struct ssh *ssh
monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSIGN, 1);
}
return (0);
}
@@ -1904,8 +1933,8 @@ mm_answer_gss_checkmic(struct ssh *ssh,
OM_uint32 ret;
int r;
- if (!options.gss_authentication)
- fatal_f("GSSAPI authentication not enabled");
+ if (!options.gss_authentication && !options.gss_keyex)
+ fatal_f("GSSAPI not enabled");
if ((r = ssh_gssapi_get_buffer_desc(m, &gssbuf)) != 0 ||
(r = ssh_gssapi_get_buffer_desc(m, &mic)) != 0)
@@ -1931,13 +1960,17 @@ mm_answer_gss_checkmic(struct ssh *ssh,
int
mm_answer_gss_userok(struct ssh *ssh, int sock, struct sshbuf *m)
{
- int r, authenticated;
+ int r, authenticated, kex;
const char *displayname;
- if (!options.gss_authentication)
- fatal_f("GSSAPI authentication not enabled");
+ if (!options.gss_authentication && !options.gss_keyex)
+ fatal_f("GSSAPI not enabled");
- authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
+ if ((r = sshbuf_get_u32(m, &kex)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+ authenticated = authctxt->valid &&
+ ssh_gssapi_userok(authctxt->user, authctxt->pw, kex);
sshbuf_reset(m);
if ((r = sshbuf_put_u32(m, authenticated)) != 0)
@@ -1946,7 +1979,11 @@ mm_answer_gss_userok(struct ssh *ssh, in
debug3_f("sending result %d", authenticated);
mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
- auth_method = "gssapi-with-mic";
+ if (kex) {
+ auth_method = "gssapi-keyex";
+ } else {
+ auth_method = "gssapi-with-mic";
+ }
if ((displayname = ssh_gssapi_displayname()) != NULL)
auth2_record_info(authctxt, "%s", displayname);
@@ -1954,5 +1991,85 @@ mm_answer_gss_userok(struct ssh *ssh, in
/* Monitor loop will terminate if authenticated */
return (authenticated);
}
+
+int
+mm_answer_gss_sign(struct ssh *ssh, int socket, struct sshbuf *m)
+{
+ gss_buffer_desc data;
+ gss_buffer_desc hash = GSS_C_EMPTY_BUFFER;
+ OM_uint32 major, minor;
+ size_t len;
+ u_char *p = NULL;
+ int r;
+
+ if (!options.gss_authentication && !options.gss_keyex)
+ fatal("%s: GSSAPI not enabled", __func__);
+
+ if ((r = sshbuf_get_string(m, &p, &len)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+ data.value = p;
+ data.length = len;
+ /* Lengths of SHA-1, SHA-256 and SHA-512 hashes that are used */
+ if (data.length != 20 && data.length != 32 && data.length != 64)
+ fatal("%s: data length incorrect: %d", __func__,
+ (int) data.length);
+
+ /* Save the session ID on the first time around */
+ if (session_id2_len == 0) {
+ session_id2_len = data.length;
+ session_id2 = xmalloc(session_id2_len);
+ memcpy(session_id2, data.value, session_id2_len);
+ }
+ major = ssh_gssapi_sign(gsscontext, &data, &hash);
+
+ free(data.value);
+
+ sshbuf_reset(m);
+
+ if ((r = sshbuf_put_u32(m, major)) != 0 ||
+ (r = sshbuf_put_string(m, hash.value, hash.length)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+ mm_request_send(socket, MONITOR_ANS_GSSSIGN, m);
+
+ gss_release_buffer(&minor, &hash);
+
+ /* Turn on getpwnam permissions */
+ monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
+
+ /* And credential updating, for when rekeying */
+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSUPCREDS, 1);
+
+ return (0);
+}
+
+int
+mm_answer_gss_updatecreds(struct ssh *ssh, int socket, struct sshbuf *m) {
+ ssh_gssapi_ccache store;
+ int r, ok;
+
+ if (!options.gss_authentication && !options.gss_keyex)
+ fatal("%s: GSSAPI not enabled", __func__);
+
+ if ((r = sshbuf_get_string(m, (u_char **)&store.filename, NULL)) != 0 ||
+ (r = sshbuf_get_string(m, (u_char **)&store.envvar, NULL)) != 0 ||
+ (r = sshbuf_get_string(m, (u_char **)&store.envval, NULL)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+ ok = ssh_gssapi_update_creds(&store);
+
+ free(store.filename);
+ free(store.envvar);
+ free(store.envval);
+
+ sshbuf_reset(m);
+ if ((r = sshbuf_put_u32(m, ok)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+ mm_request_send(socket, MONITOR_ANS_GSSUPCREDS, m);
+
+ return(0);
+}
+
#endif /* GSSAPI */
Index: openssh-8.9p1/monitor.h
===================================================================
--- openssh-8.9p1.orig/monitor.h
+++ openssh-8.9p1/monitor.h
@@ -63,6 +63,8 @@ enum monitor_reqtype {
MONITOR_REQ_PAM_FREE_CTX = 110, MONITOR_ANS_PAM_FREE_CTX = 111,
MONITOR_REQ_AUDIT_EVENT = 112, MONITOR_REQ_AUDIT_COMMAND = 113,
+ MONITOR_REQ_GSSSIGN = 150, MONITOR_ANS_GSSSIGN = 151,
+ MONITOR_REQ_GSSUPCREDS = 152, MONITOR_ANS_GSSUPCREDS = 153,
};
struct ssh;
Index: openssh-8.9p1/monitor_wrap.c
===================================================================
--- openssh-8.9p1.orig/monitor_wrap.c
+++ openssh-8.9p1/monitor_wrap.c
@@ -999,13 +999,15 @@ mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss
}
int
-mm_ssh_gssapi_userok(char *user)
+mm_ssh_gssapi_userok(char *user, struct passwd *pw, int kex)
{
struct sshbuf *m;
int r, authenticated = 0;
if ((m = sshbuf_new()) == NULL)
fatal_f("sshbuf_new failed");
+ if ((r = sshbuf_put_u32(m, kex)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, m);
mm_request_receive_expect(pmonitor->m_recvfd,
@@ -1018,4 +1020,57 @@ mm_ssh_gssapi_userok(char *user)
debug3_f("user %sauthenticated", authenticated ? "" : "not ");
return (authenticated);
}
+
+OM_uint32
+mm_ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_desc *data, gss_buffer_desc *hash)
+{
+ struct sshbuf *m;
+ OM_uint32 major;
+ int r;
+
+ if ((m = sshbuf_new()) == NULL)
+ fatal("%s: sshbuf_new failed", __func__);
+ if ((r = sshbuf_put_string(m, data->value, data->length)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+ mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSIGN, m);
+ mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSIGN, m);
+
+ if ((r = sshbuf_get_u32(m, &major)) != 0 ||
+ (r = ssh_gssapi_get_buffer_desc(m, hash)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+ sshbuf_free(m);
+
+ return (major);
+}
+
+int
+mm_ssh_gssapi_update_creds(ssh_gssapi_ccache *store)
+{
+ struct sshbuf *m;
+ int r, ok;
+
+ if ((m = sshbuf_new()) == NULL)
+ fatal("%s: sshbuf_new failed", __func__);
+
+ if ((r = sshbuf_put_cstring(m,
+ store->filename ? store->filename : "")) != 0 ||
+ (r = sshbuf_put_cstring(m,
+ store->envvar ? store->envvar : "")) != 0 ||
+ (r = sshbuf_put_cstring(m,
+ store->envval ? store->envval : "")) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+ mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUPCREDS, m);
+ mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUPCREDS, m);
+
+ if ((r = sshbuf_get_u32(m, &ok)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+ sshbuf_free(m);
+
+ return (ok);
+}
+
#endif /* GSSAPI */
Index: openssh-8.9p1/monitor_wrap.h
===================================================================
--- openssh-8.9p1.orig/monitor_wrap.h
+++ openssh-8.9p1/monitor_wrap.h
@@ -65,8 +65,10 @@ int mm_sshkey_verify(const struct sshkey
OM_uint32 mm_ssh_gssapi_server_ctx(Gssctxt **, gss_OID);
OM_uint32 mm_ssh_gssapi_accept_ctx(Gssctxt *,
gss_buffer_desc *, gss_buffer_desc *, OM_uint32 *);
-int mm_ssh_gssapi_userok(char *user);
+int mm_ssh_gssapi_userok(char *user, struct passwd *, int kex);
OM_uint32 mm_ssh_gssapi_checkmic(Gssctxt *, gss_buffer_t, gss_buffer_t);
+OM_uint32 mm_ssh_gssapi_sign(Gssctxt *, gss_buffer_t, gss_buffer_t);
+int mm_ssh_gssapi_update_creds(ssh_gssapi_ccache *);
#endif
#ifdef USE_PAM
Index: openssh-8.9p1/readconf.c
===================================================================
--- openssh-8.9p1.orig/readconf.c
+++ openssh-8.9p1/readconf.c
@@ -67,6 +67,7 @@
#include "uidswap.h"
#include "myproposal.h"
#include "digest.h"
+#include "ssh-gss.h"
#include "fips.h"
@@ -163,6 +164,8 @@ typedef enum {
oClearAllForwardings, oNoHostAuthenticationForLocalhost,
oEnableSSHKeysign, oRekeyLimit, oVerifyHostKeyDNS, oConnectTimeout,
oAddressFamily, oGssAuthentication, oGssDelegateCreds,
+ oGssTrustDns, oGssKeyEx, oGssClientIdentity, oGssRenewalRekey,
+ oGssServerIdentity, oGssKexAlgorithms,
oServerAliveInterval, oServerAliveCountMax, oIdentitiesOnly,
oSendEnv, oSetEnv, oControlPath, oControlMaster, oControlPersist,
oHashKnownHosts,
@@ -208,10 +211,22 @@ static struct {
/* Sometimes-unsupported options */
#if defined(GSSAPI)
{ "gssapiauthentication", oGssAuthentication },
+ { "gssapikeyexchange", oGssKeyEx },
{ "gssapidelegatecredentials", oGssDelegateCreds },
+ { "gssapitrustdns", oGssTrustDns },
+ { "gssapiclientidentity", oGssClientIdentity },
+ { "gssapiserveridentity", oGssServerIdentity },
+ { "gssapirenewalforcesrekey", oGssRenewalRekey },
+ { "gssapikexalgorithms", oGssKexAlgorithms },
# else
{ "gssapiauthentication", oUnsupported },
+ { "gssapikeyexchange", oUnsupported },
{ "gssapidelegatecredentials", oUnsupported },
+ { "gssapitrustdns", oUnsupported },
+ { "gssapiclientidentity", oUnsupported },
+ { "gssapiserveridentity", oUnsupported },
+ { "gssapirenewalforcesrekey", oUnsupported },
+ { "gssapikexalgorithms", oUnsupported },
#endif
#ifdef ENABLE_PKCS11
{ "pkcs11provider", oPKCS11Provider },
@@ -1125,10 +1140,42 @@ parse_time:
intptr = &options->gss_authentication;
goto parse_flag;
+ case oGssKeyEx:
+ intptr = &options->gss_keyex;
+ goto parse_flag;
+
case oGssDelegateCreds:
intptr = &options->gss_deleg_creds;
goto parse_flag;
+ case oGssTrustDns:
+ intptr = &options->gss_trust_dns;
+ goto parse_flag;
+
+ case oGssClientIdentity:
+ charptr = &options->gss_client_identity;
+ goto parse_string;
+
+ case oGssServerIdentity:
+ charptr = &options->gss_server_identity;
+ goto parse_string;
+
+ case oGssRenewalRekey:
+ intptr = &options->gss_renewal_rekey;
+ goto parse_flag;
+
+ case oGssKexAlgorithms:
+ arg = argv_next(&ac, &av);
+ if (!arg || *arg == '\0')
+ fatal("%.200s line %d: Missing argument.",
+ filename, linenum);
+ if (!kex_gss_names_valid(arg))
+ fatal("%.200s line %d: Bad GSSAPI KexAlgorithms '%s'.",
+ filename, linenum, arg ? arg : "<NONE>");
+ if (*activep && options->gss_kex_algorithms == NULL)
+ options->gss_kex_algorithms = xstrdup(arg);
+ break;
+
case oBatchMode:
intptr = &options->batch_mode;
goto parse_flag;
@@ -2361,7 +2408,13 @@ initialize_options(Options * options)
options->fwd_opts.streamlocal_bind_unlink = -1;
options->pubkey_authentication = -1;
options->gss_authentication = -1;
+ options->gss_keyex = -1;
options->gss_deleg_creds = -1;
+ options->gss_trust_dns = -1;
+ options->gss_renewal_rekey = -1;
+ options->gss_client_identity = NULL;
+ options->gss_server_identity = NULL;
+ options->gss_kex_algorithms = NULL;
options->password_authentication = -1;
options->kbd_interactive_authentication = -1;
options->kbd_interactive_devices = NULL;
@@ -2518,8 +2571,18 @@ fill_default_options(Options * options)
options->pubkey_authentication = SSH_PUBKEY_AUTH_ALL;
if (options->gss_authentication == -1)
options->gss_authentication = 0;
+ if (options->gss_keyex == -1)
+ options->gss_keyex = 0;
if (options->gss_deleg_creds == -1)
options->gss_deleg_creds = 0;
+ if (options->gss_trust_dns == -1)
+ options->gss_trust_dns = 0;
+ if (options->gss_renewal_rekey == -1)
+ options->gss_renewal_rekey = 0;
+#ifdef GSSAPI
+ if (options->gss_kex_algorithms == NULL)
+ options->gss_kex_algorithms = strdup(GSS_KEX_DEFAULT_KEX);
+#endif
if (options->password_authentication == -1)
options->password_authentication = 1;
if (options->kbd_interactive_authentication == -1)
@@ -3317,7 +3380,14 @@ dump_client_config(Options *o, const cha
dump_cfg_fmtint(oGatewayPorts, o->fwd_opts.gateway_ports);
#ifdef GSSAPI
dump_cfg_fmtint(oGssAuthentication, o->gss_authentication);
+ dump_cfg_fmtint(oGssKeyEx, o->gss_keyex);
dump_cfg_fmtint(oGssDelegateCreds, o->gss_deleg_creds);
+ dump_cfg_fmtint(oGssTrustDns, o->gss_trust_dns);
+ dump_cfg_fmtint(oGssRenewalRekey, o->gss_renewal_rekey);
+ dump_cfg_string(oGssClientIdentity, o->gss_client_identity);
+ dump_cfg_string(oGssServerIdentity, o->gss_server_identity);
+ dump_cfg_string(oGssKexAlgorithms, o->gss_kex_algorithms ?
+ o->gss_kex_algorithms : GSS_KEX_DEFAULT_KEX);
#endif /* GSSAPI */
dump_cfg_fmtint(oHashKnownHosts, o->hash_known_hosts);
dump_cfg_fmtint(oHostbasedAuthentication, o->hostbased_authentication);
Index: openssh-8.9p1/readconf.h
===================================================================
--- openssh-8.9p1.orig/readconf.h
+++ openssh-8.9p1/readconf.h
@@ -39,7 +39,13 @@ typedef struct {
int pubkey_authentication; /* Try ssh2 pubkey authentication. */
int hostbased_authentication; /* ssh2's rhosts_rsa */
int gss_authentication; /* Try GSS authentication */
+ int gss_keyex; /* Try GSS key exchange */
int gss_deleg_creds; /* Delegate GSS credentials */
+ int gss_trust_dns; /* Trust DNS for GSS canonicalization */
+ int gss_renewal_rekey; /* Credential renewal forces rekey */
+ char *gss_client_identity; /* Principal to initiate GSSAPI with */
+ char *gss_server_identity; /* GSSAPI target principal */
+ char *gss_kex_algorithms; /* GSSAPI kex methods to be offered by client. */
int password_authentication; /* Try password
* authentication. */
int kbd_interactive_authentication; /* Try keyboard-interactive auth. */
Index: openssh-8.9p1/servconf.c
===================================================================
--- openssh-8.9p1.orig/servconf.c
+++ openssh-8.9p1/servconf.c
@@ -70,6 +70,7 @@
#include "auth.h"
#include "myproposal.h"
#include "digest.h"
+#include "ssh-gss.h"
#include "fips.h"
static void add_listen_addr(ServerOptions *, const char *,
@@ -138,8 +139,11 @@ initialize_server_options(ServerOptions
options->kerberos_ticket_cleanup = -1;
options->kerberos_get_afs_token = -1;
options->gss_authentication=-1;
+ options->gss_keyex = -1;
options->gss_cleanup_creds = -1;
options->gss_strict_acceptor = -1;
+ options->gss_store_rekey = -1;
+ options->gss_kex_algorithms = NULL;
options->password_authentication = -1;
options->kbd_interactive_authentication = -1;
options->permit_empty_passwd = -1;
@@ -379,10 +383,18 @@ fill_default_server_options(ServerOption
options->kerberos_get_afs_token = 0;
if (options->gss_authentication == -1)
options->gss_authentication = 0;
+ if (options->gss_keyex == -1)
+ options->gss_keyex = 0;
if (options->gss_cleanup_creds == -1)
options->gss_cleanup_creds = 1;
if (options->gss_strict_acceptor == -1)
options->gss_strict_acceptor = 1;
+ if (options->gss_store_rekey == -1)
+ options->gss_store_rekey = 0;
+#ifdef GSSAPI
+ if (options->gss_kex_algorithms == NULL)
+ options->gss_kex_algorithms = strdup(GSS_KEX_DEFAULT_KEX);
+#endif
if (options->password_authentication == -1)
options->password_authentication = 1;
if (options->kbd_interactive_authentication == -1)
@@ -530,6 +542,7 @@ typedef enum {
sHostKeyAlgorithms, sPerSourceMaxStartups, sPerSourceNetBlockSize,
sClientAliveInterval, sClientAliveCountMax, sAuthorizedKeysFile,
sGssAuthentication, sGssCleanupCreds, sGssStrictAcceptor,
+ sGssKeyEx, sGssKexAlgorithms, sGssStoreRekey,
sAcceptEnv, sSetEnv, sPermitTunnel,
sMatch, sPermitOpen, sPermitListen, sForceCommand, sChrootDirectory,
sUsePrivilegeSeparation, sAllowAgentForwarding,
@@ -613,12 +626,22 @@ static struct {
#ifdef GSSAPI
{ "gssapiauthentication", sGssAuthentication, SSHCFG_ALL },
{ "gssapicleanupcredentials", sGssCleanupCreds, SSHCFG_GLOBAL },
+ { "gssapicleanupcreds", sGssCleanupCreds, SSHCFG_GLOBAL },
{ "gssapistrictacceptorcheck", sGssStrictAcceptor, SSHCFG_GLOBAL },
+ { "gssapikeyexchange", sGssKeyEx, SSHCFG_GLOBAL },
+ { "gssapistorecredentialsonrekey", sGssStoreRekey, SSHCFG_GLOBAL },
+ { "gssapikexalgorithms", sGssKexAlgorithms, SSHCFG_GLOBAL },
#else
{ "gssapiauthentication", sUnsupported, SSHCFG_ALL },
{ "gssapicleanupcredentials", sUnsupported, SSHCFG_GLOBAL },
+ { "gssapicleanupcreds", sUnsupported, SSHCFG_GLOBAL },
{ "gssapistrictacceptorcheck", sUnsupported, SSHCFG_GLOBAL },
+ { "gssapikeyexchange", sUnsupported, SSHCFG_GLOBAL },
+ { "gssapistorecredentialsonrekey", sUnsupported, SSHCFG_GLOBAL },
+ { "gssapikexalgorithms", sUnsupported, SSHCFG_GLOBAL },
#endif
+ { "gssusesessionccache", sUnsupported, SSHCFG_GLOBAL },
+ { "gssapiusesessioncredcache", sUnsupported, SSHCFG_GLOBAL },
{ "passwordauthentication", sPasswordAuthentication, SSHCFG_ALL },
{ "kbdinteractiveauthentication", sKbdInteractiveAuthentication, SSHCFG_ALL },
{ "challengeresponseauthentication", sKbdInteractiveAuthentication, SSHCFG_ALL }, /* alias */
@@ -1603,6 +1626,10 @@ process_server_config_line_depth(ServerO
intptr = &options->gss_authentication;
goto parse_flag;
+ case sGssKeyEx:
+ intptr = &options->gss_keyex;
+ goto parse_flag;
+
case sGssCleanupCreds:
intptr = &options->gss_cleanup_creds;
goto parse_flag;
@@ -1611,6 +1638,22 @@ process_server_config_line_depth(ServerO
intptr = &options->gss_strict_acceptor;
goto parse_flag;
+ case sGssStoreRekey:
+ intptr = &options->gss_store_rekey;
+ goto parse_flag;
+
+ case sGssKexAlgorithms:
+ arg = argv_next(&ac, &av);
+ if (!arg || *arg == '\0')
+ fatal("%.200s line %d: Missing argument.",
+ filename, linenum);
+ if (!kex_gss_names_valid(arg))
+ fatal("%.200s line %d: Bad GSSAPI KexAlgorithms '%s'.",
+ filename, linenum, arg ? arg : "<NONE>");
+ if (*activep && options->gss_kex_algorithms == NULL)
+ options->gss_kex_algorithms = xstrdup(arg);
+ break;
+
case sPasswordAuthentication:
intptr = &options->password_authentication;
goto parse_flag;
@@ -2918,6 +2961,10 @@ dump_config(ServerOptions *o)
#ifdef GSSAPI
dump_cfg_fmtint(sGssAuthentication, o->gss_authentication);
dump_cfg_fmtint(sGssCleanupCreds, o->gss_cleanup_creds);
+ dump_cfg_fmtint(sGssKeyEx, o->gss_keyex);
+ dump_cfg_fmtint(sGssStrictAcceptor, o->gss_strict_acceptor);
+ dump_cfg_fmtint(sGssStoreRekey, o->gss_store_rekey);
+ dump_cfg_string(sGssKexAlgorithms, o->gss_kex_algorithms);
#endif
dump_cfg_fmtint(sPasswordAuthentication, o->password_authentication);
dump_cfg_fmtint(sKbdInteractiveAuthentication,
Index: openssh-8.9p1/servconf.h
===================================================================
--- openssh-8.9p1.orig/servconf.h
+++ openssh-8.9p1/servconf.h
@@ -141,8 +141,11 @@ typedef struct {
int kerberos_get_afs_token; /* If true, try to get AFS token if
* authenticated with Kerberos. */
int gss_authentication; /* If true, permit GSSAPI authentication */
+ int gss_keyex; /* If true, permit GSSAPI key exchange */
int gss_cleanup_creds; /* If true, destroy cred cache on logout */
int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */
+ int gss_store_rekey;
+ char *gss_kex_algorithms; /* GSSAPI kex methods to be offered by client. */
int password_authentication; /* If true, permit password
* authentication. */
int kbd_interactive_authentication; /* If true, permit */
Index: openssh-8.9p1/session.c
===================================================================
--- openssh-8.9p1.orig/session.c
+++ openssh-8.9p1/session.c
@@ -2708,13 +2708,19 @@ do_cleanup(struct ssh *ssh, Authctxt *au
#ifdef KRB5
if (options.kerberos_ticket_cleanup &&
- authctxt->krb5_ctx)
+ authctxt->krb5_ctx) {
+ temporarily_use_uid(authctxt->pw);
krb5_cleanup_proc(authctxt);
+ restore_uid();
+ }
#endif
#ifdef GSSAPI
- if (options.gss_cleanup_creds)
+ if (options.gss_cleanup_creds) {
+ temporarily_use_uid(authctxt->pw);
ssh_gssapi_cleanup_creds();
+ restore_uid();
+ }
#endif
/* remove agent socket */
Index: openssh-8.9p1/ssh-gss.h
===================================================================
--- openssh-8.9p1.orig/ssh-gss.h
+++ openssh-8.9p1/ssh-gss.h
@@ -1,6 +1,6 @@
/* $OpenBSD: ssh-gss.h,v 1.15 2021/01/27 10:05:28 djm Exp $ */
/*
- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
+ * Copyright (c) 2001-2009 Simon Wilkinson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -61,10 +61,30 @@
#define SSH_GSS_OIDTYPE 0x06
+#define SSH2_MSG_KEXGSS_INIT 30
+#define SSH2_MSG_KEXGSS_CONTINUE 31
+#define SSH2_MSG_KEXGSS_COMPLETE 32
+#define SSH2_MSG_KEXGSS_HOSTKEY 33
+#define SSH2_MSG_KEXGSS_ERROR 34
+#define SSH2_MSG_KEXGSS_GROUPREQ 40
+#define SSH2_MSG_KEXGSS_GROUP 41
+#define KEX_GSS_GRP1_SHA1_ID "gss-group1-sha1-"
+#define KEX_GSS_GRP14_SHA1_ID "gss-group14-sha1-"
+#define KEX_GSS_GRP14_SHA256_ID "gss-group14-sha256-"
+#define KEX_GSS_GRP16_SHA512_ID "gss-group16-sha512-"
+#define KEX_GSS_GEX_SHA1_ID "gss-gex-sha1-"
+#define KEX_GSS_NISTP256_SHA256_ID "gss-nistp256-sha256-"
+#define KEX_GSS_C25519_SHA256_ID "gss-curve25519-sha256-"
+
+#define GSS_KEX_DEFAULT_KEX \
+ KEX_GSS_GEX_SHA1_ID "," \
+ KEX_GSS_GRP14_SHA1_ID
+
typedef struct {
char *filename;
char *envvar;
char *envval;
+ struct passwd *owner;
void *data;
} ssh_gssapi_ccache;
@@ -72,8 +92,11 @@ typedef struct {
gss_buffer_desc displayname;
gss_buffer_desc exportedname;
gss_cred_id_t creds;
+ gss_name_t name;
struct ssh_gssapi_mech_struct *mech;
ssh_gssapi_ccache store;
+ int used;
+ int updated;
} ssh_gssapi_client;
typedef struct ssh_gssapi_mech_struct {
@@ -84,6 +107,7 @@ typedef struct ssh_gssapi_mech_struct {
int (*userok) (ssh_gssapi_client *, char *);
int (*localname) (ssh_gssapi_client *, char **);
void (*storecreds) (ssh_gssapi_client *);
+ int (*updatecreds) (ssh_gssapi_ccache *, ssh_gssapi_client *);
} ssh_gssapi_mech;
typedef struct {
@@ -94,10 +118,11 @@ typedef struct {
gss_OID oid; /* client */
gss_cred_id_t creds; /* server */
gss_name_t client; /* server */
- gss_cred_id_t client_creds; /* server */
+ gss_cred_id_t client_creds; /* both */
} Gssctxt;
extern ssh_gssapi_mech *supported_mechs[];
+extern Gssctxt *gss_kex_context;
int ssh_gssapi_check_oid(Gssctxt *, void *, size_t);
void ssh_gssapi_set_oid_data(Gssctxt *, void *, size_t);
@@ -109,6 +134,7 @@ OM_uint32 ssh_gssapi_test_oid_supported(
struct sshbuf;
int ssh_gssapi_get_buffer_desc(struct sshbuf *, gss_buffer_desc *);
+int ssh_gssapi_sshpkt_get_buffer_desc(struct ssh *, gss_buffer_desc *);
OM_uint32 ssh_gssapi_import_name(Gssctxt *, const char *);
OM_uint32 ssh_gssapi_init_ctx(Gssctxt *, int,
@@ -123,17 +149,33 @@ void ssh_gssapi_delete_ctx(Gssctxt **);
OM_uint32 ssh_gssapi_sign(Gssctxt *, gss_buffer_t, gss_buffer_t);
void ssh_gssapi_buildmic(struct sshbuf *, const char *,
const char *, const char *, const struct sshbuf *);
-int ssh_gssapi_check_mechanism(Gssctxt **, gss_OID, const char *);
+int ssh_gssapi_check_mechanism(Gssctxt **, gss_OID, const char *, const char *);
+OM_uint32 ssh_gssapi_client_identity(Gssctxt *, const char *);
+int ssh_gssapi_credentials_updated(Gssctxt *);
/* In the server */
+typedef int ssh_gssapi_check_fn(Gssctxt **, gss_OID, const char *,
+ const char *);
+char *ssh_gssapi_client_mechanisms(const char *, const char *, const char *);
+char *ssh_gssapi_kex_mechs(gss_OID_set, ssh_gssapi_check_fn *, const char *,
+ const char *, const char *);
+gss_OID ssh_gssapi_id_kex(Gssctxt *, char *, int);
+int ssh_gssapi_server_check_mech(Gssctxt **,gss_OID, const char *,
+ const char *);
OM_uint32 ssh_gssapi_server_ctx(Gssctxt **, gss_OID);
-int ssh_gssapi_userok(char *name);
+int ssh_gssapi_userok(char *, struct passwd *, int kex);
OM_uint32 ssh_gssapi_checkmic(Gssctxt *, gss_buffer_t, gss_buffer_t);
void ssh_gssapi_do_child(char ***, u_int *);
void ssh_gssapi_cleanup_creds(void);
void ssh_gssapi_storecreds(void);
const char *ssh_gssapi_displayname(void);
+char *ssh_gssapi_server_mechanisms(void);
+int ssh_gssapi_oid_table_ok(void);
+
+int ssh_gssapi_update_creds(ssh_gssapi_ccache *store);
+void ssh_gssapi_rekey_creds(void);
+
#endif /* GSSAPI */
#endif /* _SSH_GSS_H */
Index: openssh-8.9p1/ssh.1
===================================================================
--- openssh-8.9p1.orig/ssh.1
+++ openssh-8.9p1/ssh.1
@@ -530,7 +530,13 @@ For full details of the options listed b
.It GatewayPorts
.It GlobalKnownHostsFile
.It GSSAPIAuthentication
+.It GSSAPIKeyExchange
+.It GSSAPIClientIdentity
.It GSSAPIDelegateCredentials
+.It GSSAPIKexAlgorithms
+.It GSSAPIRenewalForcesRekey
+.It GSSAPIServerIdentity
+.It GSSAPITrustDns
.It HashKnownHosts
.It Host
.It HostbasedAcceptedAlgorithms
@@ -607,6 +613,8 @@ flag),
(supported message integrity codes),
.Ar kex
(key exchange algorithms),
+.Ar kex-gss
+(GSSAPI key exchange algorithms),
.Ar key
(key types),
.Ar key-cert
Index: openssh-8.9p1/ssh.c
===================================================================
--- openssh-8.9p1.orig/ssh.c
+++ openssh-8.9p1/ssh.c
@@ -781,6 +781,8 @@ main(int ac, char **av)
else if (strcmp(optarg, "kex") == 0 ||
strcasecmp(optarg, "KexAlgorithms") == 0)
cp = kex_alg_list('\n');
+ else if (strcmp(optarg, "kex-gss") == 0)
+ cp = kex_gss_alg_list('\n');
else if (strcmp(optarg, "key") == 0)
cp = sshkey_alg_list(0, 0, 0, '\n');
else if (strcmp(optarg, "key-cert") == 0)
@@ -807,7 +809,7 @@ main(int ac, char **av)
cp[n] = '\n';
} else if (strcmp(optarg, "help") == 0) {
cp = xstrdup(
- "cipher\ncipher-auth\ncompression\nkex\n"
+ "cipher\ncipher-auth\ncompression\nkex\nkex-gss\n"
"key\nkey-cert\nkey-plain\nkey-sig\nmac\n"
"protocol-version\nsig");
}
Index: openssh-8.9p1/ssh_config
===================================================================
--- openssh-8.9p1.orig/ssh_config
+++ openssh-8.9p1/ssh_config
@@ -40,6 +40,8 @@ Host *
# HostbasedAuthentication no
# GSSAPIAuthentication no
# GSSAPIDelegateCredentials no
+# GSSAPIKeyExchange no
+# GSSAPITrustDNS no
# BatchMode no
# CheckHostIP yes
# AddressFamily any
Index: openssh-8.9p1/ssh_config.5
===================================================================
--- openssh-8.9p1.orig/ssh_config.5
+++ openssh-8.9p1/ssh_config.5
@@ -835,10 +835,67 @@ The default is
Specifies whether user authentication based on GSSAPI is allowed.
The default is
.Cm no .
+.It Cm GSSAPIClientIdentity
+If set, specifies the GSSAPI client identity that ssh should use when
+connecting to the server. The default is unset, which means that the default
+identity will be used.
.It Cm GSSAPIDelegateCredentials
Forward (delegate) credentials to the server.
The default is
.Cm no .
+.It Cm GSSAPIKeyExchange
+Specifies whether key exchange based on GSSAPI may be used. When using
+GSSAPI key exchange the server need not have a host key.
+The default is
+.Dq no .
+.It Cm GSSAPIRenewalForcesRekey
+If set to
+.Dq yes
+then renewal of the client's GSSAPI credentials will force the rekeying of the
+ssh connection. With a compatible server, this will delegate the renewed
+credentials to a session on the server.
+.Pp
+Checks are made to ensure that credentials are only propagated when the new
+credentials match the old ones on the originating client and where the
+receiving server still has the old set in its cache.
+.Pp
+The default is
+.Dq no .
+.Pp
+For this to work
+.Cm GSSAPIKeyExchange
+needs to be enabled in the server and also used by the client.
+.It Cm GSSAPIServerIdentity
+If set, specifies the GSSAPI server identity that ssh should expect when
+connecting to the server. The default is unset, which means that the
+expected GSSAPI server identity will be determined from the target
+hostname.
+.It Cm GSSAPITrustDns
+Set to
+.Dq yes
+to indicate that the DNS is trusted to securely canonicalize
+the name of the host being connected to. If
+.Dq no ,
+the hostname entered on the
+command line will be passed untouched to the GSSAPI library.
+The default is
+.Dq no .
+.It Cm GSSAPIKexAlgorithms
+The list of key exchange algorithms that are offered for GSSAPI
+key exchange. Possible values are
+.Bd -literal -offset 3n
+gss-gex-sha1-,
+gss-group1-sha1-,
+gss-group14-sha1-,
+gss-group14-sha256-,
+gss-group16-sha512-,
+gss-nistp256-sha256-,
+gss-curve25519-sha256-
+.Ed
+.Pp
+The default is
+.Dq gss-gex-sha1-,gss-group14-sha1- .
+This option only applies to protocol version 2 connections using GSSAPI.
.It Cm HashKnownHosts
Indicates that
.Xr ssh 1
Index: openssh-8.9p1/sshconnect2.c
===================================================================
--- openssh-8.9p1.orig/sshconnect2.c
+++ openssh-8.9p1/sshconnect2.c
@@ -81,8 +81,6 @@
#endif
/* import */
-extern char *client_version_string;
-extern char *server_version_string;
extern Options options;
/*
@@ -220,6 +218,11 @@ ssh_kex2(struct ssh *ssh, char *host, st
char *s, *all_key;
int r, use_known_hosts_order = 0;
+#if defined(GSSAPI) && defined(WITH_OPENSSL)
+ char *orig = NULL, *gss = NULL;
+ char *gss_host = NULL;
+#endif
+
xxx_host = host;
xxx_hostaddr = hostaddr;
xxx_conn_info = cinfo;
@@ -264,6 +267,35 @@ ssh_kex2(struct ssh *ssh, char *host, st
compat_pkalg_proposal(ssh, options.hostkeyalgorithms);
}
+#if defined(GSSAPI) && defined(WITH_OPENSSL)
+ if (options.gss_keyex) {
+ /* Add the GSSAPI mechanisms currently supported on this
+ * client to the key exchange algorithm proposal */
+ orig = myproposal[PROPOSAL_KEX_ALGS];
+
+ if (options.gss_server_identity)
+ gss_host = xstrdup(options.gss_server_identity);
+ else if (options.gss_trust_dns)
+ gss_host = remote_hostname(ssh);
+ else
+ gss_host = xstrdup(host);
+
+ gss = ssh_gssapi_client_mechanisms(gss_host,
+ options.gss_client_identity, options.gss_kex_algorithms);
+ if (gss) {
+ debug("Offering GSSAPI proposal: %s", gss);
+ xasprintf(&myproposal[PROPOSAL_KEX_ALGS],
+ "%s,%s", gss, orig);
+
+ /* If we've got GSSAPI algorithms, then we also support the
+ * 'null' hostkey, as a last resort */
+ orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
+ xasprintf(&myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS],
+ "%s,null", orig);
+ }
+ }
+#endif
+
if (options.rekey_limit || options.rekey_interval)
ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
options.rekey_interval);
@@ -282,16 +314,46 @@ ssh_kex2(struct ssh *ssh, char *host, st
# ifdef OPENSSL_HAS_ECC
ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
# endif
-#endif
+# ifdef GSSAPI
+ if (options.gss_keyex) {
+ ssh->kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_client;
+ ssh->kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_client;
+ ssh->kex->kex[KEX_GSS_GRP14_SHA256] = kexgss_client;
+ ssh->kex->kex[KEX_GSS_GRP16_SHA512] = kexgss_client;
+ ssh->kex->kex[KEX_GSS_GEX_SHA1] = kexgssgex_client;
+ ssh->kex->kex[KEX_GSS_NISTP256_SHA256] = kexgss_client;
+ ssh->kex->kex[KEX_GSS_C25519_SHA256] = kexgss_client;
+ }
+# endif
+#endif /* WITH_OPENSSL */
ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
ssh->kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_client;
ssh->kex->verify_host_key=&verify_host_key_callback;
+#if defined(GSSAPI) && defined(WITH_OPENSSL)
+ if (options.gss_keyex) {
+ ssh->kex->gss_deleg_creds = options.gss_deleg_creds;
+ ssh->kex->gss_trust_dns = options.gss_trust_dns;
+ ssh->kex->gss_client = options.gss_client_identity;
+ ssh->kex->gss_host = gss_host;
+ }
+#endif
+
ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
/* remove ext-info from the KEX proposals for rekeying */
myproposal[PROPOSAL_KEX_ALGS] =
compat_kex_proposal(ssh, options.kex_algorithms);
+#if defined(GSSAPI) && defined(WITH_OPENSSL)
+ /* repair myproposal after it was crumpled by the */
+ /* ext-info removal above */
+ if (gss) {
+ orig = myproposal[PROPOSAL_KEX_ALGS];
+ xasprintf(&myproposal[PROPOSAL_KEX_ALGS],
+ "%s,%s", gss, orig);
+ free(gss);
+ }
+#endif
if ((r = kex_prop2buf(ssh->kex->my, myproposal)) != 0)
fatal_r(r, "kex_prop2buf");
@@ -385,6 +447,7 @@ static int input_gssapi_response(int typ
static int input_gssapi_token(int type, u_int32_t, struct ssh *);
static int input_gssapi_error(int, u_int32_t, struct ssh *);
static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
+static int userauth_gsskeyex(struct ssh *);
#endif
void userauth(struct ssh *, char *);
@@ -401,6 +464,11 @@ static char *authmethods_get(void);
Authmethod authmethods[] = {
#ifdef GSSAPI
+ {"gssapi-keyex",
+ userauth_gsskeyex,
+ NULL,
+ &options.gss_keyex,
+ NULL},
{"gssapi-with-mic",
userauth_gssapi,
userauth_gssapi_cleanup,
@@ -776,12 +844,23 @@ userauth_gssapi(struct ssh *ssh)
OM_uint32 min;
int r, ok = 0;
gss_OID mech = NULL;
+ char *gss_host;
+
+ if (options.gss_server_identity)
+ gss_host = xstrdup(options.gss_server_identity);
+ else if (options.gss_trust_dns)
+ gss_host = remote_hostname(ssh);
+ else
+ gss_host = xstrdup(authctxt->host);
/* Try one GSSAPI method at a time, rather than sending them all at
* once. */
if (authctxt->gss_supported_mechs == NULL)
- gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
+ if (GSS_ERROR(gss_indicate_mechs(&min, &authctxt->gss_supported_mechs))) {
+ free(gss_host);
+ return 0;
+ }
/* Check to see whether the mechanism is usable before we offer it */
while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
@@ -790,13 +869,15 @@ userauth_gssapi(struct ssh *ssh)
elements[authctxt->mech_tried];
/* My DER encoding requires length<128 */
if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
- mech, authctxt->host)) {
+ mech, gss_host, options.gss_client_identity)) {
ok = 1; /* Mechanism works */
} else {
authctxt->mech_tried++;
}
}
+ free(gss_host);
+
if (!ok || mech == NULL)
return 0;
@@ -1037,6 +1118,55 @@ input_gssapi_error(int type, u_int32_t p
free(lang);
return r;
}
+
+int
+userauth_gsskeyex(struct ssh *ssh)
+{
+ struct sshbuf *b = NULL;
+ Authctxt *authctxt = ssh->authctxt;
+ gss_buffer_desc gssbuf;
+ gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
+ OM_uint32 ms;
+ int r;
+
+ static int attempt = 0;
+ if (attempt++ >= 1)
+ return (0);
+
+ if (gss_kex_context == NULL) {
+ debug("No valid Key exchange context");
+ return (0);
+ }
+
+ if ((b = sshbuf_new()) == NULL)
+ fatal("%s: sshbuf_new failed", __func__);
+
+ ssh_gssapi_buildmic(b, authctxt->server_user, authctxt->service,
+ "gssapi-keyex", ssh->kex->session_id);
+
+ if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
+ fatal("%s: sshbuf_mutable_ptr failed", __func__);
+ gssbuf.length = sshbuf_len(b);
+
+ if (GSS_ERROR(ssh_gssapi_sign(gss_kex_context, &gssbuf, &mic))) {
+ sshbuf_free(b);
+ return (0);
+ }
+
+ if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
+ (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
+ (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
+ (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
+ (r = sshpkt_put_string(ssh, mic.value, mic.length)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ fatal("%s: %s", __func__, ssh_err(r));
+
+ sshbuf_free(b);
+ gss_release_buffer(&ms, &mic);
+
+ return (1);
+}
+
#endif /* GSSAPI */
static int
Index: openssh-8.9p1/sshd.c
===================================================================
--- openssh-8.9p1.orig/sshd.c
+++ openssh-8.9p1/sshd.c
@@ -813,8 +813,8 @@ notify_hostkeys(struct ssh *ssh)
}
debug3_f("sent %u hostkeys", nkeys);
if (nkeys == 0)
- fatal_f("no hostkeys");
- if ((r = sshpkt_send(ssh)) != 0)
+ debug3("%s: no hostkeys", __func__);
+ else if ((r = sshpkt_send(ssh)) != 0)
sshpkt_fatal(ssh, r, "%s: send", __func__);
sshbuf_free(buf);
}
@@ -1909,7 +1909,8 @@ main(int ac, char **av)
free(fp);
}
accumulate_host_timing_secret(cfg, NULL);
- if (!sensitive_data.have_ssh2_key) {
+ /* The GSSAPI key exchange can run without a host key */
+ if (!sensitive_data.have_ssh2_key && !options.gss_keyex) {
logit("sshd: no hostkeys available -- exiting.");
exit(1);
}
@@ -2397,6 +2398,48 @@ do_ssh2_kex(struct ssh *ssh)
myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = compat_pkalg_proposal(
ssh, list_hostkey_types());
+#if defined(GSSAPI) && defined(WITH_OPENSSL)
+ {
+ char *orig;
+ char *gss = NULL;
+ char *newstr = NULL;
+ orig = myproposal[PROPOSAL_KEX_ALGS];
+
+ /*
+ * If we don't have a host key, then there's no point advertising
+ * the other key exchange algorithms
+ */
+
+ if (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS]) == 0)
+ orig = NULL;
+
+ if (options.gss_keyex)
+ gss = ssh_gssapi_server_mechanisms();
+ else
+ gss = NULL;
+
+ if (gss && orig)
+ xasprintf(&newstr, "%s,%s", gss, orig);
+ else if (gss)
+ newstr = gss;
+ else if (orig)
+ newstr = orig;
+
+ /*
+ * If we've got GSSAPI mechanisms, then we've got the 'null' host
+ * key alg, but we can't tell people about it unless its the only
+ * host key algorithm we support
+ */
+ if (gss && (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS])) == 0)
+ myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = "null";
+
+ if (newstr)
+ myproposal[PROPOSAL_KEX_ALGS] = newstr;
+ else
+ fatal("No supported key exchange algorithms");
+ }
+#endif
+
/* start key exchange */
if ((r = kex_setup(ssh, myproposal)) != 0)
fatal_r(r, "kex_setup");
@@ -2412,7 +2455,18 @@ do_ssh2_kex(struct ssh *ssh)
# ifdef OPENSSL_HAS_ECC
kex->kex[KEX_ECDH_SHA2] = kex_gen_server;
# endif
-#endif
+# ifdef GSSAPI
+ if (options.gss_keyex) {
+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server;
+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_server;
+ kex->kex[KEX_GSS_GRP14_SHA256] = kexgss_server;
+ kex->kex[KEX_GSS_GRP16_SHA512] = kexgss_server;
+ kex->kex[KEX_GSS_GEX_SHA1] = kexgssgex_server;
+ kex->kex[KEX_GSS_NISTP256_SHA256] = kexgss_server;
+ kex->kex[KEX_GSS_C25519_SHA256] = kexgss_server;
+ }
+# endif
+#endif /* WITH_OPENSSL */
kex->kex[KEX_C25519_SHA256] = kex_gen_server;
kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_server;
kex->load_host_public_key=&get_hostkey_public_by_type;
Index: openssh-8.9p1/sshd_config
===================================================================
--- openssh-8.9p1.orig/sshd_config
+++ openssh-8.9p1/sshd_config
@@ -69,6 +69,8 @@ AuthorizedKeysFile .ssh/authorized_keys
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
+#GSSAPIStrictAcceptorCheck yes
+#GSSAPIKeyExchange no
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
Index: openssh-8.9p1/sshd_config.5
===================================================================
--- openssh-8.9p1.orig/sshd_config.5
+++ openssh-8.9p1/sshd_config.5
@@ -652,6 +652,11 @@ Specifies whether to automatically destr
on logout.
The default is
.Cm yes .
+.It Cm GSSAPIKeyExchange
+Specifies whether key exchange based on GSSAPI is allowed. GSSAPI key exchange
+doesn't rely on ssh keys to verify host identity.
+The default is
+.Cm no .
.It Cm GSSAPIStrictAcceptorCheck
Determines whether to be strict about the identity of the GSSAPI acceptor
a client authenticates against.
@@ -666,6 +671,31 @@ machine's default store.
This facility is provided to assist with operation on multi homed machines.
The default is
.Cm yes .
+.It Cm GSSAPIStoreCredentialsOnRekey
+Controls whether the user's GSSAPI credentials should be updated following a
+successful connection rekeying. This option can be used to accepted renewed
+or updated credentials from a compatible client. The default is
+.Dq no .
+.Pp
+For this to work
+.Cm GSSAPIKeyExchange
+needs to be enabled in the server and also used by the client.
+.It Cm GSSAPIKexAlgorithms
+The list of key exchange algorithms that are accepted by GSSAPI
+key exchange. Possible values are
+.Bd -literal -offset 3n
+gss-gex-sha1-,
+gss-group1-sha1-,
+gss-group14-sha1-,
+gss-group14-sha256-,
+gss-group16-sha512-,
+gss-nistp256-sha256-,
+gss-curve25519-sha256-
+.Ed
+.Pp
+The default is
+.Dq gss-gex-sha1-,gss-group14-sha1- .
+This option only applies to protocol version 2 connections using GSSAPI.
.It Cm HostbasedAcceptedAlgorithms
Specifies the signature algorithms that will be accepted for hostbased
authentication as a list of comma-separated patterns.
Index: openssh-8.9p1/sshkey.c
===================================================================
--- openssh-8.9p1.orig/sshkey.c
+++ openssh-8.9p1/sshkey.c
@@ -162,6 +162,7 @@ static const struct keytype keytypes[] =
# endif /* ENABLE_SK */
# endif /* OPENSSL_HAS_ECC */
#endif /* WITH_OPENSSL */
+ { "null", "null", NULL, KEY_NULL, 0, 0, 0 },
{ NULL, NULL, NULL, -1, -1, 0, 0 }
};
@@ -286,7 +287,7 @@ sshkey_alg_list(int certs_only, int plai
const struct keytype *kt;
for (kt = keytypes; kt->type != -1; kt++) {
- if (kt->name == NULL)
+ if (kt->name == NULL || kt->type == KEY_NULL)
continue;
if (!include_sigonly && kt->sigonly)
continue;
Index: openssh-8.9p1/sshkey.h
===================================================================
--- openssh-8.9p1.orig/sshkey.h
+++ openssh-8.9p1/sshkey.h
@@ -71,6 +71,7 @@ enum sshkey_types {
KEY_ECDSA_SK_CERT,
KEY_ED25519_SK,
KEY_ED25519_SK_CERT,
+ KEY_NULL,
KEY_UNSPEC
};
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