audit-linux.c

   1 /* $Id: audit-linux.c,v 1.1 2011/01/17 10:15:30 dtucker Exp $ */
   2
   3 /*
   4  * Copyright 2010 Red Hat, Inc.  All rights reserved.
   5  * Use is subject to license terms.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  *
  27  * Red Hat author: Jan F. Chadima <jchadima@redhat.com>
  28  */
  29
  30 #include "includes.h"
  31 #if defined(USE_LINUX_AUDIT)
  32 #include <libaudit.h>
  33 #include <unistd.h>
  34 #include <string.h>
  35
  36 #include "log.h"
  37 #include "audit.h"
  38 #include "canohost.h"
  39
  40 const char* audit_username(void);
  41
  42 int
  43 linux_audit_record_event(int uid, const char *username,
  44     const char *hostname, const char *ip, const char *ttyn, int success)
  45 {
  46         int audit_fd, rc, saved_errno;
  47
  48         audit_fd = audit_open();
  49         if (audit_fd < 0) {
  50                 if (errno == EINVAL || errno == EPROTONOSUPPORT ||
  51                     errno == EAFNOSUPPORT)
  52                         return 1; /* No audit support in kernel */
  53                 else
  54                         return 0; /* Must prevent login */
  55         }
  56         rc = audit_log_acct_message(audit_fd, AUDIT_USER_LOGIN,
  57             NULL, "login", username ? username : "(unknown)",
  58             username == NULL ? uid : -1, hostname, ip, ttyn, success);
  59         saved_errno = errno;
  60         close(audit_fd);
  61         /*
  62          * Do not report error if the error is EPERM and sshd is run as non
  63          * root user.
  64          */
  65         if ((rc == -EPERM) && (geteuid() != 0))
  66                 rc = 0;
  67         errno = saved_errno;
  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 }
  77         /* not implemented */
  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,
  89             NULL, 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(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
 110         case SSH_AUTH_FAIL_NONE:
 111         case SSH_AUTH_FAIL_PASSWD:
 112         case SSH_AUTH_FAIL_KBDINT:
 113         case SSH_AUTH_FAIL_PUBKEY:
 114         case SSH_AUTH_FAIL_HOSTBASED:
 115         case SSH_AUTH_FAIL_GSSAPI:
 116         case SSH_INVALID_USER:
 117                 linux_audit_record_event(-1, audit_username(), NULL,
 118                         get_remote_ipaddr(), "sshd", 0);
 119                 break;
 120
 121         default:
 122                 debug("%s: unhandled event %d", __func__, event);
 123         }
 124 }
 125
 126 #endif /* USE_LINUX_AUDIT */