crypto/openssh/audit-linux.c

   1 /*
   2  * Copyright 2010 Red Hat, Inc.  All rights reserved.
   3  * Use is subject to license terms.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  *
  25  * Red Hat author: Jan F. Chadima <jchadima@redhat.com>
  26  */
  27
  28 #include "includes.h"
  29 #if defined(USE_LINUX_AUDIT)
  30 #include <libaudit.h>
  31 #include <unistd.h>
  32 #include <string.h>
  33
  34 #include "log.h"
  35 #include "audit.h"
  36 #include "canohost.h"
  37 #include "packet.h"
  38
  39 const char *audit_username(void);
  40
  41 int
  42 linux_audit_record_event(int uid, const char *username, const char *hostname,
  43     const char *ip, const char *ttyn, int success)
  44 {
  45         int audit_fd, rc, saved_errno;
  46
  47         if ((audit_fd = audit_open()) < 0) {
  48                 if (errno == EINVAL || errno == EPROTONOSUPPORT ||
  49                     errno == EAFNOSUPPORT)
  50                         return 1; /* No audit support in kernel */
  51                 else
  52                         return 0; /* Must prevent login */
  53         }
  54         rc = audit_log_acct_message(audit_fd, AUDIT_USER_LOGIN,
  55             NULL, "login", username ? username : "(unknown)",
  56             username == NULL ? uid : -1, hostname, ip, ttyn, success);
  57         saved_errno = errno;
  58         close(audit_fd);
  59
  60         /*
  61          * Do not report error if the error is EPERM and sshd is run as non
  62          * root user.
  63          */
  64         if ((rc == -EPERM) && (geteuid() != 0))
  65                 rc = 0;
  66         errno = saved_errno;
  67
  68         return rc >= 0;
  69 }
  70
  71 /* Below is the sshd audit API code */
  72
  73 void
  74 audit_connection_from(const char *host, int port)
  75 {
  76         /* not implemented */
  77 }
  78
  79 void
  80 audit_run_command(const char *command)
  81 {
  82         /* not implemented */
  83 }
  84
  85 void
  86 audit_session_open(struct logininfo *li)
  87 {
  88         if (linux_audit_record_event(li->uid, NULL, li->hostname, NULL,
  89             li->line, 1) == 0)
  90                 fatal("linux_audit_write_entry failed: %s", strerror(errno));
  91 }
  92
  93 void
  94 audit_session_close(struct logininfo *li)
  95 {
  96         /* not implemented */
  97 }
  98
  99 void
 100 audit_event(struct ssh *ssh, ssh_audit_event_t event)
 101 {
 102         switch(event) {
 103         case SSH_AUTH_SUCCESS:
 104         case SSH_CONNECTION_CLOSE:
 105         case SSH_NOLOGIN:
 106         case SSH_LOGIN_EXCEED_MAXTRIES:
 107         case SSH_LOGIN_ROOT_DENIED:
 108                 break;
 109         case SSH_AUTH_FAIL_NONE:
 110         case SSH_AUTH_FAIL_PASSWD:
 111         case SSH_AUTH_FAIL_KBDINT:
 112         case SSH_AUTH_FAIL_PUBKEY:
 113         case SSH_AUTH_FAIL_HOSTBASED:
 114         case SSH_AUTH_FAIL_GSSAPI:
 115         case SSH_INVALID_USER:
 116                 linux_audit_record_event(-1, audit_username(), NULL,
 117                     ssh_remote_ipaddr(ssh), "sshd", 0);
 118                 break;
 119         default:
 120                 debug("%s: unhandled event %d", __func__, event);
 121                 break;
 122         }
 123 }
 124 #endif /* USE_LINUX_AUDIT */