openssh/openssh-6.6p1-keycat.patch
Hans Petter Jansson 74e20db9ed Accepting request 1123220 from home:jsegitz:branches:network
- Enhanced SELinux functionality. Added Fedora patches:
  * openssh-7.8p1-role-mls.patch
    Proper handling of MLS systems and basis for other SELinux
    improvements
  * openssh-6.6p1-privsep-selinux.patch
    Properly set contexts during privilege separation
  * openssh-6.6p1-keycat.patch
    Add ssh-keycat command to allow retrival of authorized_keys
    on MLS setups with polyinstantiation
  * openssh-6.6.1p1-selinux-contexts.patch
    Additional changes to set the proper context during privilege 
    separation
  * openssh-7.6p1-cleanup-selinux.patch
    Various changes and putting the pieces together
  For now we don't ship the ssh-keycat command, but we need the patch
  for the other SELinux infrastructure
  This change fixes issues like bsc#1214788, where the ssh daemon 
  needs to act on behalf of a user and needs a proper context for this

OBS-URL: https://build.opensuse.org/request/show/1123220
OBS-URL: https://build.opensuse.org/package/show/network/openssh?expand=0&rev=252
2023-11-28 16:35:34 +00:00

492 lines
14 KiB
Diff

Index: openssh-9.3p2/misc.c
===================================================================
--- openssh-9.3p2.orig/misc.c
+++ openssh-9.3p2/misc.c
@@ -2770,6 +2770,13 @@ subprocess(const char *tag, const char *
error("%s: dup2: %s", tag, strerror(errno));
_exit(1);
}
+#ifdef WITH_SELINUX
+ if (sshd_selinux_setup_env_variables() < 0) {
+ error ("failed to copy environment: %s",
+ strerror(errno));
+ _exit(127);
+ }
+#endif
if (env != NULL)
execve(av[0], av, env);
else
Index: openssh-9.3p2/HOWTO.ssh-keycat
===================================================================
--- /dev/null
+++ openssh-9.3p2/HOWTO.ssh-keycat
@@ -0,0 +1,12 @@
+The ssh-keycat retrieves the content of the ~/.ssh/authorized_keys
+of an user in any environment. This includes environments with
+polyinstantiation of home directories and SELinux MLS policy enabled.
+
+To use ssh-keycat, set these options in /etc/ssh/sshd_config file:
+ AuthorizedKeysCommand /usr/libexec/openssh/ssh-keycat
+ AuthorizedKeysCommandUser root
+
+Do not forget to enable public key authentication:
+ PubkeyAuthentication yes
+
+
Index: openssh-9.3p2/Makefile.in
===================================================================
--- openssh-9.3p2.orig/Makefile.in
+++ openssh-9.3p2/Makefile.in
@@ -24,6 +24,7 @@ SSH_PROGRAM=@bindir@/ssh
ASKPASS_PROGRAM=$(libexecdir)/ssh-askpass
SFTP_SERVER=$(libexecdir)/sftp-server
SSH_KEYSIGN=$(libexecdir)/ssh-keysign
+SSH_KEYCAT=$(libexecdir)/ssh-keycat
SSH_PKCS11_HELPER=$(libexecdir)/ssh-pkcs11-helper
SSH_SK_HELPER=$(libexecdir)/ssh-sk-helper
SSH_LDAP_HELPER=$(libexecdir)/ssh-ldap-helper
@@ -57,6 +58,7 @@ CHANNELLIBS=@CHANNELLIBS@
K5LIBS=@K5LIBS@
GSSLIBS=@GSSLIBS@
SSHDLIBS=@SSHDLIBS@
+KEYCATLIBS=@KEYCATLIBS@
LIBEDIT=@LIBEDIT@
LIBFIDO2=@LIBFIDO2@
LIBWTMPDB=@LIBWTMPDB@
@@ -75,7 +77,7 @@ MKDIR_P=@MKDIR_P@
.SUFFIXES: .lo
-TARGETS=ssh$(EXEEXT) sshd$(EXEEXT) ssh-add$(EXEEXT) ssh-keygen$(EXEEXT) ssh-keyscan${EXEEXT} ssh-keysign${EXEEXT} ssh-pkcs11-helper$(EXEEXT) ssh-agent$(EXEEXT) scp$(EXEEXT) sftp-server$(EXEEXT) sftp$(EXEEXT) ssh-sk-helper$(EXEEXT)
+TARGETS=ssh$(EXEEXT) sshd$(EXEEXT) ssh-add$(EXEEXT) ssh-keygen$(EXEEXT) ssh-keyscan${EXEEXT} ssh-keysign${EXEEXT} ssh-pkcs11-helper$(EXEEXT) ssh-agent$(EXEEXT) scp$(EXEEXT) sftp-server$(EXEEXT) sftp$(EXEEXT) ssh-sk-helper$(EXEEXT) ssh-keycat$(EXEEXT)
TARGETS += cavstest-ctr$(EXEEXT) cavstest-kdf$(EXEEXT)
@@ -245,6 +247,9 @@ ssh-pkcs11-helper$(EXEEXT): $(LIBCOMPAT)
ssh-sk-helper$(EXEEXT): $(LIBCOMPAT) libssh.a $(SKHELPER_OBJS)
$(LD) -o $@ $(SKHELPER_OBJS) $(LDFLAGS) -lssh -lopenbsd-compat -lssh -lopenbsd-compat $(LIBS) $(LIBFIDO2) $(CHANNELLIBS)
+ssh-keycat$(EXEEXT): $(LIBCOMPAT) $(SSHDOBJS) libssh.a ssh-keycat.o uidswap.o
+ $(LD) -o $@ ssh-keycat.o uidswap.o $(LDFLAGS) -lssh -lopenbsd-compat $(KEYCATLIBS) $(LIBS)
+
ssh-keyscan$(EXEEXT): $(LIBCOMPAT) libssh.a $(SSHKEYSCAN_OBJS)
$(LD) -o $@ $(SSHKEYSCAN_OBJS) $(LDFLAGS) -lssh -lopenbsd-compat -lssh $(LIBS) $(CHANNELLIBS)
@@ -431,6 +436,7 @@ install-files:
$(INSTALL) -m 0755 ssh-ldap-wrapper $(DESTDIR)$(SSH_LDAP_WRAPPER) ; \
fi
$(INSTALL) -m 0755 $(STRIP_OPT) ssh-sk-helper$(EXEEXT) $(DESTDIR)$(SSH_SK_HELPER)$(EXEEXT)
+ $(INSTALL) -m 0755 $(STRIP_OPT) ssh-keycat$(EXEEXT) $(DESTDIR)$(libexecdir)/ssh-keycat$(EXEEXT)
$(INSTALL) -m 0755 $(STRIP_OPT) sftp$(EXEEXT) $(DESTDIR)$(bindir)/sftp$(EXEEXT)
$(INSTALL) -m 0755 $(STRIP_OPT) sftp-server$(EXEEXT) $(DESTDIR)$(SFTP_SERVER)$(EXEEXT)
$(INSTALL) -m 0755 $(STRIP_OPT) cavstest-ctr$(EXEEXT) $(DESTDIR)$(libexecdir)/cavstest-ctr$(EXEEXT)
Index: openssh-9.3p2/openbsd-compat/port-linux.h
===================================================================
--- openssh-9.3p2.orig/openbsd-compat/port-linux.h
+++ openssh-9.3p2/openbsd-compat/port-linux.h
@@ -23,8 +23,10 @@ void ssh_selinux_setup_pty(char *, const
void ssh_selinux_change_context(const char *);
void ssh_selinux_setfscreatecon(const char *);
+int sshd_selinux_enabled(void);
void sshd_selinux_copy_context(void);
void sshd_selinux_setup_exec_context(char *);
+int sshd_selinux_setup_env_variables(void);
#endif
#ifdef LINUX_OOM_ADJUST
Index: openssh-9.3p2/openbsd-compat/port-linux-sshd.c
===================================================================
--- openssh-9.3p2.orig/openbsd-compat/port-linux-sshd.c
+++ openssh-9.3p2/openbsd-compat/port-linux-sshd.c
@@ -53,6 +53,20 @@ extern Authctxt *the_authctxt;
extern int inetd_flag;
extern int rexeced_flag;
+/* Wrapper around is_selinux_enabled() to log its return value once only */
+int
+sshd_selinux_enabled(void)
+{
+ static int enabled = -1;
+
+ if (enabled == -1) {
+ enabled = (is_selinux_enabled() == 1);
+ debug("SELinux support %s", enabled ? "enabled" : "disabled");
+ }
+
+ return (enabled);
+}
+
/* Send audit message */
static int
sshd_selinux_send_audit_message(int success, security_context_t default_context,
@@ -318,7 +332,7 @@ sshd_selinux_getctxbyname(char *pwname,
/* Setup environment variables for pam_selinux */
static int
-sshd_selinux_setup_pam_variables(void)
+sshd_selinux_setup_variables(int(*set_it)(char *, const char *))
{
const char *reqlvl;
char *role;
@@ -329,16 +343,16 @@ sshd_selinux_setup_pam_variables(void)
ssh_selinux_get_role_level(&role, &reqlvl);
- rv = do_pam_putenv("SELINUX_ROLE_REQUESTED", role ? role : "");
+ rv = set_it("SELINUX_ROLE_REQUESTED", role ? role : "");
if (inetd_flag && !rexeced_flag) {
use_current = "1";
} else {
use_current = "";
- rv = rv || do_pam_putenv("SELINUX_LEVEL_REQUESTED", reqlvl ? reqlvl: "");
+ rv = rv || set_it("SELINUX_LEVEL_REQUESTED", reqlvl ? reqlvl: "");
}
- rv = rv || do_pam_putenv("SELINUX_USE_CURRENT_RANGE", use_current);
+ rv = rv || set_it("SELINUX_USE_CURRENT_RANGE", use_current);
if (role != NULL)
free(role);
@@ -346,6 +360,24 @@ sshd_selinux_setup_pam_variables(void)
return rv;
}
+static int
+sshd_selinux_setup_pam_variables(void)
+{
+ return sshd_selinux_setup_variables(do_pam_putenv);
+}
+
+static int
+do_setenv(char *name, const char *value)
+{
+ return setenv(name, value, 1);
+}
+
+int
+sshd_selinux_setup_env_variables(void)
+{
+ return sshd_selinux_setup_variables(do_setenv);
+}
+
/* Set the execution context to the default for the specified user */
void
sshd_selinux_setup_exec_context(char *pwname)
@@ -354,7 +386,7 @@ sshd_selinux_setup_exec_context(char *pw
int r = 0;
security_context_t default_ctx = NULL;
- if (!ssh_selinux_enabled())
+ if (!sshd_selinux_enabled())
return;
if (options.use_pam) {
@@ -421,7 +453,7 @@ sshd_selinux_copy_context(void)
{
security_context_t *ctx;
- if (!ssh_selinux_enabled())
+ if (!sshd_selinux_enabled())
return;
if (getexeccon((security_context_t *)&ctx) != 0) {
Index: openssh-9.3p2/platform.c
===================================================================
--- openssh-9.3p2.orig/platform.c
+++ openssh-9.3p2/platform.c
@@ -100,7 +100,7 @@ platform_setusercontext(struct passwd *p
{
#ifdef WITH_SELINUX
/* Cache selinux status for later use */
- (void)ssh_selinux_enabled();
+ (void)sshd_selinux_enabled();
#endif
#ifdef USE_SOLARIS_PROJECTS
Index: openssh-9.3p2/ssh-keycat.c
===================================================================
--- /dev/null
+++ openssh-9.3p2/ssh-keycat.c
@@ -0,0 +1,241 @@
+/*
+ * 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, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``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.
+ */
+
+/*
+ * Copyright (c) 2011 Red Hat, Inc.
+ * Written by Tomas Mraz <tmraz@redhat.com>
+*/
+
+#define _GNU_SOURCE
+
+#include "config.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <pwd.h>
+#include <fcntl.h>
+#include <unistd.h>
+#ifdef HAVE_STDINT_H
+#include <stdint.h>
+#endif
+
+#include <security/pam_appl.h>
+
+#include "uidswap.h"
+#include "misc.h"
+
+#define ERR_USAGE 1
+#define ERR_PAM_START 2
+#define ERR_OPEN_SESSION 3
+#define ERR_CLOSE_SESSION 4
+#define ERR_PAM_END 5
+#define ERR_GETPWNAM 6
+#define ERR_MEMORY 7
+#define ERR_OPEN 8
+#define ERR_FILE_MODE 9
+#define ERR_FDOPEN 10
+#define ERR_STAT 11
+#define ERR_WRITE 12
+#define ERR_PAM_PUTENV 13
+#define BUFLEN 4096
+
+/* Just ignore the messages in the conversation function */
+static int
+dummy_conv(int num_msg, const struct pam_message **msgm,
+ struct pam_response **response, void *appdata_ptr)
+{
+ struct pam_response *rsp;
+
+ (void)msgm;
+ (void)appdata_ptr;
+
+ if (num_msg <= 0)
+ return PAM_CONV_ERR;
+
+ /* Just allocate the array as empty responses */
+ rsp = calloc (num_msg, sizeof (struct pam_response));
+ if (rsp == NULL)
+ return PAM_CONV_ERR;
+
+ *response = rsp;
+ return PAM_SUCCESS;
+}
+
+static struct pam_conv conv = {
+ dummy_conv,
+ NULL
+};
+
+char *
+make_auth_keys_name(const struct passwd *pwd)
+{
+ char *fname;
+
+ if (asprintf(&fname, "%s/.ssh/authorized_keys", pwd->pw_dir) < 0)
+ return NULL;
+
+ return fname;
+}
+
+int
+dump_keys(const char *user)
+{
+ struct passwd *pwd;
+ int fd = -1;
+ FILE *f = NULL;
+ char *fname = NULL;
+ int rv = 0;
+ char buf[BUFLEN];
+ size_t len;
+ struct stat st;
+
+ if ((pwd = getpwnam(user)) == NULL) {
+ return ERR_GETPWNAM;
+ }
+
+ if ((fname = make_auth_keys_name(pwd)) == NULL) {
+ return ERR_MEMORY;
+ }
+
+ temporarily_use_uid(pwd);
+
+ if ((fd = open(fname, O_RDONLY|O_NONBLOCK|O_NOFOLLOW, 0)) < 0) {
+ rv = ERR_OPEN;
+ goto fail;
+ }
+
+ if (fstat(fd, &st) < 0) {
+ rv = ERR_STAT;
+ goto fail;
+ }
+
+ if (!S_ISREG(st.st_mode) ||
+ (st.st_uid != pwd->pw_uid && st.st_uid != 0)) {
+ rv = ERR_FILE_MODE;
+ goto fail;
+ }
+
+ unset_nonblock(fd);
+
+ if ((f = fdopen(fd, "r")) == NULL) {
+ rv = ERR_FDOPEN;
+ goto fail;
+ }
+
+ fd = -1;
+
+ while ((len = fread(buf, 1, sizeof(buf), f)) > 0) {
+ rv = fwrite(buf, 1, len, stdout) != len ? ERR_WRITE : 0;
+ }
+
+fail:
+ if (fd != -1)
+ close(fd);
+ if (f != NULL)
+ fclose(f);
+ free(fname);
+ restore_uid();
+ return rv;
+}
+
+static const char *env_names[] = { "SELINUX_ROLE_REQUESTED",
+ "SELINUX_LEVEL_REQUESTED",
+ "SELINUX_USE_CURRENT_RANGE"
+};
+
+extern char **environ;
+
+int
+set_pam_environment(pam_handle_t *pamh)
+{
+ int i;
+ size_t j;
+
+ for (j = 0; j < sizeof(env_names)/sizeof(env_names[0]); ++j) {
+ int len = strlen(env_names[j]);
+
+ for (i = 0; environ[i] != NULL; ++i) {
+ if (strncmp(env_names[j], environ[i], len) == 0 &&
+ environ[i][len] == '=') {
+ if (pam_putenv(pamh, environ[i]) != PAM_SUCCESS)
+ return ERR_PAM_PUTENV;
+ }
+ }
+ }
+
+ return 0;
+}
+
+int
+main(int argc, char *argv[])
+{
+ pam_handle_t *pamh = NULL;
+ int retval;
+ int ev = 0;
+
+ if (argc != 2) {
+ fprintf(stderr, "Usage: %s <user-name>\n", argv[0]);
+ return ERR_USAGE;
+ }
+
+ retval = pam_start("ssh-keycat", argv[1], &conv, &pamh);
+ if (retval != PAM_SUCCESS) {
+ return ERR_PAM_START;
+ }
+
+ ev = set_pam_environment(pamh);
+ if (ev != 0)
+ goto finish;
+
+ retval = pam_open_session(pamh, PAM_SILENT);
+ if (retval != PAM_SUCCESS) {
+ ev = ERR_OPEN_SESSION;
+ goto finish;
+ }
+
+ ev = dump_keys(argv[1]);
+
+ retval = pam_close_session(pamh, PAM_SILENT);
+ if (retval != PAM_SUCCESS) {
+ ev = ERR_CLOSE_SESSION;
+ }
+
+finish:
+ retval = pam_end (pamh,retval);
+ if (retval != PAM_SUCCESS) {
+ ev = ERR_PAM_END;
+ }
+ return ev;
+}
Index: openssh-9.3p2/configure.ac
===================================================================
--- openssh-9.3p2.orig/configure.ac
+++ openssh-9.3p2/configure.ac
@@ -3632,6 +3632,7 @@ AC_ARG_WITH([pam],
PAM_MSG="yes"
SSHDLIBS="$SSHDLIBS -lpam"
+ KEYCATLIBS="$KEYCATLIBS -lpam"
AC_DEFINE([USE_PAM], [1],
[Define if you want to enable PAM support])
@@ -3642,6 +3643,7 @@ AC_ARG_WITH([pam],
;;
*)
SSHDLIBS="$SSHDLIBS -ldl"
+ KEYCATLIBS="$KEYCATLIBS -ldl"
;;
esac
fi
@@ -4875,6 +4877,7 @@ AC_ARG_WITH([selinux],
fi ]
)
AC_SUBST([SSHDLIBS])
+AC_SUBST([KEYCATLIBS])
# Check whether user wants Kerberos 5 support
KRB5_MSG="no"
@@ -5905,6 +5908,9 @@ fi
if test ! -z "${SSHDLIBS}"; then
echo " +for sshd: ${SSHDLIBS}"
fi
+if test ! -z "${KEYCATLIBS}"; then
+echo " +for ssh-keycat: ${KEYCATLIBS}"
+fi
echo ""