pool/openssh
SHA256
2
0
Fork 1
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
1c5ff2cc6c
openssh/openssh-6.6p1-audit3-key_auth_usage.patch
Petr Cerny efb05e6527 Accepting request 230097 from home:pcerny:factory 
- Update of the underlying OpenSSH to 6.6p1

- update to 6.6p1
  Security:
  * sshd(8): when using environment passing with a sshd_config(5)
    AcceptEnv pattern with a wildcard. OpenSSH prior to 6.6 could
    be tricked into accepting any enviornment variable that
    contains the characters before the wildcard character.
  Features since 6.5p1:
  * ssh(1), sshd(8): removal of the J-PAKE authentication code,
    which was experimental, never enabled and has been
    unmaintained for some time.
  * ssh(1): skip 'exec' clauses other clauses predicates failed
    to match while processing Match blocks.
  * ssh(1): if hostname canonicalisation is enabled and results
    in the destination hostname being changed, then re-parse
    ssh_config(5) files using the new destination hostname. This
    gives 'Host' and 'Match' directives that use the expanded
    hostname a chance to be applied.
  Bugfixes:
  * ssh(1): avoid spurious "getsockname failed: Bad file
    descriptor" in ssh -W. bz#2200, debian#738692
  * sshd(8): allow the shutdown(2) syscall in seccomp-bpf and
    systrace sandbox modes, as it is reachable if the connection
    is terminated during the pre-auth phase.
  * ssh(1), sshd(8): fix unsigned overflow that in SSH protocol 1
    bignum parsing. Minimum key length checks render this bug
    unexploitable to compromise SSH 1 sessions.
  * sshd_config(5): clarify behaviour of a keyword that appears
    in multiple matching Match blocks. bz#2184

OBS-URL: https://build.opensuse.org/request/show/230097
OBS-URL: https://build.opensuse.org/package/show/network/openssh?expand=0&rev=76
2014-04-14 21:53:01 +00:00

507 lines
15 KiB
Diff
Raw Blame History

# auditing key-based authentication (both server and client)
# based on:
# https://bugzilla.mindrot.org/show_bug.cgi?id=1402
# https://bugzilla.mindrot.org/attachment.cgi?id=2012
# (replaces: https://bugzilla.mindrot.org/attachment.cgi?id=1975)
# by jchadima@redhat.com
diff --git a/openssh-6.6p1/audit-bsm.c b/openssh-6.6p1/audit-bsm.c
--- a/openssh-6.6p1/audit-bsm.c
+++ b/openssh-6.6p1/audit-bsm.c
@@ -401,16 +401,22 @@ audit_session_open(struct logininfo *li)
}
void
audit_session_close(struct logininfo *li)
{
/* not implemented */
}
+int
+audit_keyusage(int host_user, const char *type, unsigned bits, char *fp, int rv)
+{
+ /* not implemented */
+}
+
void
audit_event(ssh_audit_event_t event)
{
char textbuf[BSM_TEXTBUFSZ];
static int logged_in = 0;
const char *user = the_authctxt ? the_authctxt->user : "(unknown user)";
if (cannot_audit(0))
diff --git a/openssh-6.6p1/audit-linux.c b/openssh-6.6p1/audit-linux.c
--- a/openssh-6.6p1/audit-linux.c
+++ b/openssh-6.6p1/audit-linux.c
@@ -36,16 +36,18 @@
#include "log.h"
#include "audit.h"
#include "key.h"
#include "hostfile.h"
#include "auth.h"
#include "servconf.h"
#include "canohost.h"
+#define AUDIT_LOG_SIZE 128
+
extern ServerOptions options;
extern Authctxt *the_authctxt;
extern u_int utmp_len;
const char* audit_username(void);
static void
linux_audit_user_logxxx(int uid, const char *username,
const char *hostname, const char *ip, const char *ttyn, int success, int event)
@@ -125,16 +127,47 @@ linux_audit_user_auth(int uid, const cha
rc = 0;
errno = saved_errno;
if (rc < 0) {
fatal_report:
fatal("linux_audit_write_entry failed: %s", strerror(errno));
}
}
+int
+audit_keyusage(int host_user, const char *type, unsigned bits, char *fp, int rv)
+{
+ char buf[AUDIT_LOG_SIZE];
+ int audit_fd, rc, saved_errno;
+
+ audit_fd = audit_open();
+ if (audit_fd < 0) {
+ if (errno == EINVAL || errno == EPROTONOSUPPORT ||
+ errno == EAFNOSUPPORT)
+ return 1; /* No audit support in kernel */
+ else
+ return 0; /* Must prevent login */
+ }
+ snprintf(buf, sizeof(buf), "%s_auth rport=%d", host_user ? "pubkey" : "hostbased", get_remote_port());
+ rc = audit_log_acct_message(audit_fd, AUDIT_USER_AUTH, NULL,
+ buf, audit_username(), -1, NULL, get_remote_ipaddr(), NULL, rv);
+ if ((rc < 0) && ((rc != -1) || (getuid() == 0)))
+ goto out;
+ snprintf(buf, sizeof(buf), "key algo=%s size=%d fp=%s rport=%d",
+ type, bits, fp, get_remote_port());
+ rc = audit_log_acct_message(audit_fd, AUDIT_USER_AUTH, NULL,
+ buf, audit_username(), -1, NULL, get_remote_ipaddr(), NULL, rv);
+out:
+ saved_errno = errno;
+ audit_close(audit_fd);
+ errno = saved_errno;
+ /* do not report error if the error is EPERM and sshd is run as non root user */
+ return (rc >= 0) || ((rc == -EPERM) && (getuid() != 0));
+}
+
static int user_login_count = 0;
/* Below is the sshd audit API code */
void
audit_connection_from(const char *host, int port)
{
/* not implemented */
diff --git a/openssh-6.6p1/audit.c b/openssh-6.6p1/audit.c
--- a/openssh-6.6p1/audit.c
+++ b/openssh-6.6p1/audit.c
@@ -31,16 +31,17 @@
#ifdef SSH_AUDIT_EVENTS
#include "audit.h"
#include "log.h"
#include "key.h"
#include "hostfile.h"
#include "auth.h"
+#include "xmalloc.h"
/*
* Care must be taken when using this since it WILL NOT be initialized when
* audit_connection_from() is called and MAY NOT be initialized when
* audit_event(CONNECTION_ABANDON) is called. Test for NULL before using.
*/
extern Authctxt *the_authctxt;
@@ -106,16 +107,32 @@ audit_event_lookup(ssh_audit_event_t ev)
};
for (i = 0; event_lookup[i].event != SSH_AUDIT_UNKNOWN; i++)
if (event_lookup[i].event == ev)
break;
return(event_lookup[i].name);
}
+void
+audit_key(int host_user, int *rv, const Key *key)
+{
+ char *fp;
+ const char *crypto_name;
+
+ fp = key_fingerprint(key, key_fp_type_select(), SSH_FP_HEX);
+ if (key->type == KEY_RSA1)
+ crypto_name = "ssh-rsa1";
+ else
+ crypto_name = key_ssh_name(key);
+ if (audit_keyusage(host_user, crypto_name, key_size(key), fp, *rv) == 0)
+ *rv = 0;
+ free(fp);
+}
+
# ifndef CUSTOM_SSH_AUDIT_EVENTS
/*
* Null implementations of audit functions.
* These get used if SSH_AUDIT_EVENTS is defined but no audit module is enabled.
*/
/*
* Called after a connection has been accepted but before any authentication
@@ -204,10 +221,22 @@ audit_run_command(const char *command)
*/
void
audit_end_command(int handle, const char *command)
{
debug("audit end nopty exec euid %d user %s command '%.200s'", geteuid(),
audit_username(), command);
}
+/*
+ * This will be called when user is successfully autherized by the RSA1/RSA/DSA key.
+ *
+ * Type is the key type, len is the key length(byte) and fp is the fingerprint of the key.
+ */
+int
+audit_keyusage(int host_user, const char *type, unsigned bits, char *fp, int rv)
+{
+ debug("audit %s key usage euid %d user %s key type %s key length %d fingerprint %s, result %d",
+ host_user ? "pubkey" : "hostbased", geteuid(), audit_username(), type, bits,
+ fp, rv);
+}
# endif /* !defined CUSTOM_SSH_AUDIT_EVENTS */
#endif /* SSH_AUDIT_EVENTS */
diff --git a/openssh-6.6p1/audit.h b/openssh-6.6p1/audit.h
--- a/openssh-6.6p1/audit.h
+++ b/openssh-6.6p1/audit.h
@@ -23,16 +23,17 @@
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _SSH_AUDIT_H
# define _SSH_AUDIT_H
#include "loginrec.h"
+#include "key.h"
enum ssh_audit_event_type {
SSH_LOGIN_EXCEED_MAXTRIES,
SSH_LOGIN_ROOT_DENIED,
SSH_AUTH_SUCCESS,
SSH_AUTH_FAIL_NONE,
SSH_AUTH_FAIL_PASSWD,
SSH_AUTH_FAIL_KBDINT, /* keyboard-interactive or challenge-response */
@@ -50,10 +51,12 @@ typedef enum ssh_audit_event_type ssh_au
void audit_connection_from(const char *, int);
void audit_event(ssh_audit_event_t);
void audit_count_session_open(void);
void audit_session_open(struct logininfo *);
void audit_session_close(struct logininfo *);
int audit_run_command(const char *);
void audit_end_command(int, const char *);
ssh_audit_event_t audit_classify_auth(const char *);
+int audit_keyusage(int, const char *, unsigned, char *, int);
+void audit_key(int, int *, const Key *);
#endif /* _SSH_AUDIT_H */
diff --git a/openssh-6.6p1/auth.h b/openssh-6.6p1/auth.h
--- a/openssh-6.6p1/auth.h
+++ b/openssh-6.6p1/auth.h
@@ -178,16 +178,17 @@ int allowed_user(struct passwd *);
struct passwd * getpwnamallow(const char *user);
char *get_challenge(Authctxt *);
int verify_response(Authctxt *, const char *);
void abandon_challenge_response(Authctxt *);
char *expand_authorized_keys(const char *, struct passwd *pw);
char *authorized_principals_file(struct passwd *);
+int user_key_verify(const Key *, const u_char *, u_int, const u_char *, u_int);
FILE *auth_openkeyfile(const char *, struct passwd *, int);
FILE *auth_openprincipals(const char *, struct passwd *, int);
int auth_key_is_revoked(Key *);
HostStatus
check_key_in_hostfiles(struct passwd *, Key *, const char *,
const char *, const char *);
@@ -195,16 +196,17 @@ check_key_in_hostfiles(struct passwd *,
/* hostkey handling */
Key *get_hostkey_by_index(int);
Key *get_hostkey_public_by_index(int);
Key *get_hostkey_public_by_type(int);
Key *get_hostkey_private_by_type(int);
int get_hostkey_index(Key *);
int ssh1_session_key(BIGNUM *);
void sshd_hostkey_sign(Key *, Key *, u_char **, u_int *, u_char *, u_int);
+int hostbased_key_verify(const Key *, const u_char *, u_int, const u_char *, u_int);
/* debug messages during authentication */
void auth_debug_add(const char *fmt,...) __attribute__((format(printf, 1, 2)));
void auth_debug_send(void);
void auth_debug_reset(void);
struct passwd *fakepw(void);
diff --git a/openssh-6.6p1/auth2-hostbased.c b/openssh-6.6p1/auth2-hostbased.c
--- a/openssh-6.6p1/auth2-hostbased.c
+++ b/openssh-6.6p1/auth2-hostbased.c
@@ -124,33 +124,45 @@ userauth_hostbased(Authctxt *authctxt)
#endif
pubkey_auth_info(authctxt, key,
"client user \"%.100s\", client host \"%.100s\"", cuser, chost);
/* test for allowed key and correct signature */
authenticated = 0;
if (PRIVSEP(hostbased_key_allowed(authctxt->pw, cuser, chost, key)) &&
- PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b),
+ PRIVSEP(hostbased_key_verify(key, sig, slen, buffer_ptr(&b),
buffer_len(&b))) == 1)
authenticated = 1;
buffer_free(&b);
done:
debug2("userauth_hostbased: authenticated %d", authenticated);
if (key != NULL)
key_free(key);
free(pkalg);
free(pkblob);
free(cuser);
free(chost);
free(sig);
return authenticated;
}
+int
+hostbased_key_verify(const Key *key, const u_char *sig, u_int slen, const u_char *data, u_int datalen)
+{
+ int rv;
+
+ rv = key_verify(key, sig, slen, data, datalen);
+#ifdef SSH_AUDIT_EVENTS
+ audit_key(0, &rv, key);
+#endif
+ return rv;
+}
+
/* return 1 if given hostkey is allowed */
int
hostbased_key_allowed(struct passwd *pw, const char *cuser, char *chost,
Key *key)
{
const char *resolvedname, *ipaddr, *lookup, *reason;
HostStatus host_status;
int len;
diff --git a/openssh-6.6p1/auth2-pubkey.c b/openssh-6.6p1/auth2-pubkey.c
--- a/openssh-6.6p1/auth2-pubkey.c
+++ b/openssh-6.6p1/auth2-pubkey.c
@@ -153,17 +153,17 @@ userauth_pubkey(Authctxt *authctxt)
#ifdef DEBUG_PK
buffer_dump(&b);
#endif
pubkey_auth_info(authctxt, key, NULL);
/* test for correct signature */
authenticated = 0;
if (PRIVSEP(user_key_allowed(authctxt->pw, key)) &&
- PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b),
+ PRIVSEP(user_key_verify(key, sig, slen, buffer_ptr(&b),
buffer_len(&b))) == 1)
authenticated = 1;
buffer_free(&b);
free(sig);
} else {
debug("test whether pkalg/pkblob are acceptable");
packet_check_eom();
@@ -190,16 +190,28 @@ done:
debug2("userauth_pubkey: authenticated %d pkalg %s", authenticated, pkalg);
if (key != NULL)
key_free(key);
free(pkalg);
free(pkblob);
return authenticated;
}
+int
+user_key_verify(const Key *key, const u_char *sig, u_int slen, const u_char *data, u_int datalen)
+{
+ int rv;
+
+ rv = key_verify(key, sig, slen, data, datalen);
+#ifdef SSH_AUDIT_EVENTS
+ audit_key(1, &rv, key);
+#endif
+ return rv;
+}
+
void
pubkey_auth_info(Authctxt *authctxt, const Key *key, const char *fmt, ...)
{
char *fp, *extra;
va_list ap;
int i;
extra = NULL;
diff --git a/openssh-6.6p1/monitor.c b/openssh-6.6p1/monitor.c
--- a/openssh-6.6p1/monitor.c
+++ b/openssh-6.6p1/monitor.c
@@ -1340,26 +1340,30 @@ monitor_valid_hostbasedblob(u_char *data
}
int
mm_answer_keyverify(int sock, Buffer *m)
{
Key *key;
u_char *signature, *data, *blob;
u_int signaturelen, datalen, bloblen;
+ int type = 0;
int verified = 0;
int valid_data = 0;
+ type = buffer_get_int(m);
blob = buffer_get_string(m, &bloblen);
signature = buffer_get_string(m, &signaturelen);
data = buffer_get_string(m, &datalen);
if (hostbased_cuser == NULL || hostbased_chost == NULL ||
!monitor_allowed_key(blob, bloblen))
fatal("%s: bad key, not previously allowed", __func__);
+ if (type != key_blobtype)
+ fatal("%s: bad key type", __func__);
key = key_from_blob(blob, bloblen);
if (key == NULL)
fatal("%s: bad public key blob", __func__);
switch (key_blobtype) {
case MM_USERKEY:
valid_data = monitor_valid_userblob(data, datalen);
@@ -1370,17 +1374,27 @@ mm_answer_keyverify(int sock, Buffer *m)
break;
default:
valid_data = 0;
break;
}
if (!valid_data)
fatal("%s: bad signature data blob", __func__);
- verified = key_verify(key, signature, signaturelen, data, datalen);
+ switch (key_blobtype) {
+ case MM_USERKEY:
+ verified = user_key_verify(key, signature, signaturelen, data, datalen);
+ break;
+ case MM_HOSTKEY:
+ verified = hostbased_key_verify(key, signature, signaturelen, data, datalen);
+ break;
+ default:
+ verified = 0;
+ break;
+ }
debug3("%s: key %p signature %s",
__func__, key, (verified == 1) ? "verified" : "unverified");
key_free(key);
free(blob);
free(signature);
free(data);
diff --git a/openssh-6.6p1/monitor_wrap.c b/openssh-6.6p1/monitor_wrap.c
--- a/openssh-6.6p1/monitor_wrap.c
+++ b/openssh-6.6p1/monitor_wrap.c
@@ -426,30 +426,31 @@ mm_key_allowed(enum mm_keytype type, cha
/*
* This key verify needs to send the key type along, because the
* privileged parent makes the decision if the key is allowed
* for authentication.
*/
int
-mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
+mm_key_verify(enum mm_keytype type, Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
{
Buffer m;
u_char *blob;
u_int len;
int verified = 0;
debug3("%s entering", __func__);
/* Convert the key to a blob and the pass it over */
if (!key_to_blob(key, &blob, &len))
return (0);
buffer_init(&m);
+ buffer_put_int(&m, type);
buffer_put_string(&m, blob, len);
buffer_put_string(&m, sig, siglen);
buffer_put_string(&m, data, datalen);
free(blob);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
@@ -457,16 +458,29 @@ mm_key_verify(Key *key, u_char *sig, u_i
verified = buffer_get_int(&m);
buffer_free(&m);
return (verified);
}
+int
+mm_hostbased_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
+{
+ return mm_key_verify(MM_HOSTKEY, key, sig, siglen, data, datalen);
+}
+
+int
+mm_user_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
+{
+ return mm_key_verify(MM_USERKEY, key, sig, siglen, data, datalen);
+}
+
+
/* Export key state after authentication */
Newkeys *
mm_newkeys_from_blob(u_char *blob, int blen)
{
Buffer b;
u_int len;
Newkeys *newkey = NULL;
Enc *enc;
diff --git a/openssh-6.6p1/monitor_wrap.h b/openssh-6.6p1/monitor_wrap.h
--- a/openssh-6.6p1/monitor_wrap.h
+++ b/openssh-6.6p1/monitor_wrap.h
@@ -44,17 +44,18 @@ int mm_key_sign(Key *, u_char **, u_int
void mm_inform_authserv(char *, char *);
struct passwd *mm_getpwnamallow(const char *);
char *mm_auth2_read_banner(void);
int mm_auth_password(struct Authctxt *, char *);
int mm_key_allowed(enum mm_keytype, char *, char *, Key *);
int mm_user_key_allowed(struct passwd *, Key *);
int mm_hostbased_key_allowed(struct passwd *, char *, char *, Key *);
int mm_auth_rhosts_rsa_key_allowed(struct passwd *, char *, char *, Key *);
-int mm_key_verify(Key *, u_char *, u_int, u_char *, u_int);
+int mm_hostbased_key_verify(Key *, u_char *, u_int, u_char *, u_int);
+int mm_user_key_verify(Key *, u_char *, u_int, u_char *, u_int);
int mm_auth_rsa_key_allowed(struct passwd *, BIGNUM *, Key **);
int mm_auth_rsa_verify_response(Key *, BIGNUM *, u_char *);
BIGNUM *mm_auth_rsa_generate_challenge(Key *);
#ifdef GSSAPI
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 *);
Reference in New Issue View Git Blame Copy Permalink