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-rw-r--r--audit-bsm.c454
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+/*
+ * TODO
+ *
+ * - deal with overlap between this and sys_auth_allowed_user
+ * sys_auth_record_login and record_failed_login.
+ */
+
+/*
+ * Copyright 1988-2002 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * 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.
+ *
+ */
+/* #pragma ident "@(#)bsmaudit.c 1.1 01/09/17 SMI" */
+
+#include "includes.h"
+#if defined(USE_BSM_AUDIT)
+
+#include <sys/types.h>
+
+#include <errno.h>
+#include <netdb.h>
+#include <stdarg.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifdef BROKEN_BSM_API
+#include <libscf.h>
+#endif
+
+#include "ssh.h"
+#include "log.h"
+#include "hostfile.h"
+#include "auth.h"
+#include "xmalloc.h"
+
+#ifndef AUE_openssh
+# define AUE_openssh 32800
+#endif
+#include <bsm/audit.h>
+#include <bsm/libbsm.h>
+#include <bsm/audit_uevents.h>
+#include <bsm/audit_record.h>
+#include <locale.h>
+
+#if defined(HAVE_GETAUDIT_ADDR)
+#define AuditInfoStruct auditinfo_addr
+#define AuditInfoTermID au_tid_addr_t
+#define SetAuditFunc(a,b) setaudit_addr((a),(b))
+#define SetAuditFuncText "setaudit_addr"
+#define AUToSubjectFunc au_to_subject_ex
+#define AUToReturnFunc(a,b) au_to_return32((a), (int32_t)(b))
+#else
+#define AuditInfoStruct auditinfo
+#define AuditInfoTermID au_tid_t
+#define SetAuditFunc(a,b) setaudit(a)
+#define SetAuditFuncText "setaudit"
+#define AUToSubjectFunc au_to_subject
+#define AUToReturnFunc(a,b) au_to_return((a), (u_int)(b))
+#endif
+
+#ifndef cannot_audit
+extern int cannot_audit(int);
+#endif
+extern void aug_init(void);
+extern void aug_save_auid(au_id_t);
+extern void aug_save_uid(uid_t);
+extern void aug_save_euid(uid_t);
+extern void aug_save_gid(gid_t);
+extern void aug_save_egid(gid_t);
+extern void aug_save_pid(pid_t);
+extern void aug_save_asid(au_asid_t);
+extern void aug_save_tid(dev_t, unsigned int);
+extern void aug_save_tid_ex(dev_t, u_int32_t *, u_int32_t);
+extern int aug_save_me(void);
+extern int aug_save_namask(void);
+extern void aug_save_event(au_event_t);
+extern void aug_save_sorf(int);
+extern void aug_save_text(char *);
+extern void aug_save_text1(char *);
+extern void aug_save_text2(char *);
+extern void aug_save_na(int);
+extern void aug_save_user(char *);
+extern void aug_save_path(char *);
+extern int aug_save_policy(void);
+extern void aug_save_afunc(int (*)(int));
+extern int aug_audit(void);
+extern int aug_na_selected(void);
+extern int aug_selected(void);
+extern int aug_daemon_session(void);
+
+#ifndef HAVE_GETTEXT
+# define gettext(a) (a)
+#endif
+
+extern Authctxt *the_authctxt;
+static AuditInfoTermID ssh_bsm_tid;
+
+#ifdef BROKEN_BSM_API
+/* For some reason this constant is no longer defined
+ in Solaris 11. */
+#define BSM_TEXTBUFSZ 256
+#endif
+
+/* Below is the low-level BSM interface code */
+
+/*
+ * aug_get_machine is only required on IPv6 capable machines, we use a
+ * different mechanism in audit_connection_from() for IPv4-only machines.
+ * getaudit_addr() is only present on IPv6 capable machines.
+ */
+#if defined(HAVE_AUG_GET_MACHINE) || !defined(HAVE_GETAUDIT_ADDR)
+extern int aug_get_machine(char *, u_int32_t *, u_int32_t *);
+#else
+static int
+aug_get_machine(char *host, u_int32_t *addr, u_int32_t *type)
+{
+ struct addrinfo *ai;
+ struct sockaddr_in *in4;
+ struct sockaddr_in6 *in6;
+ int ret = 0, r;
+
+ if ((r = getaddrinfo(host, NULL, NULL, &ai)) != 0) {
+ error("BSM audit: getaddrinfo failed for %.100s: %.100s", host,
+ r == EAI_SYSTEM ? strerror(errno) : gai_strerror(r));
+ return -1;
+ }
+
+ switch (ai->ai_family) {
+ case AF_INET:
+ in4 = (struct sockaddr_in *)ai->ai_addr;
+ *type = AU_IPv4;
+ memcpy(addr, &in4->sin_addr, sizeof(struct in_addr));
+ break;
+#ifdef AU_IPv6
+ case AF_INET6:
+ in6 = (struct sockaddr_in6 *)ai->ai_addr;
+ *type = AU_IPv6;
+ memcpy(addr, &in6->sin6_addr, sizeof(struct in6_addr));
+ break;
+#endif
+ default:
+ error("BSM audit: unknown address family for %.100s: %d",
+ host, ai->ai_family);
+ ret = -1;
+ }
+ freeaddrinfo(ai);
+ return ret;
+}
+#endif
+
+#ifdef BROKEN_BSM_API
+/*
+ In Solaris 11 the audit daemon has been moved to SMF. In the process
+ they simply dropped getacna() from the API, since it read from a now
+ non-existent config file. This function re-implements getacna() to
+ read from the SMF repository instead.
+ */
+int
+getacna(char *auditstring, int len)
+{
+ scf_handle_t *handle = NULL;
+ scf_property_t *property = NULL;
+ scf_value_t *value = NULL;
+ int ret = 0;
+
+ handle = scf_handle_create(SCF_VERSION);
+ if (handle == NULL)
+ return -2; /* The man page for getacna on Solaris 10 states
+ we should return -2 in case of error and set
+ errno to indicate the error. We don't bother
+ with errno here, though, since the only use
+ of this function below doesn't check for errors
+ anyway.
+ */
+
+ ret = scf_handle_bind(handle);
+ if (ret == -1)
+ return -2;
+
+ property = scf_property_create(handle);
+ if (property == NULL)
+ return -2;
+
+ ret = scf_handle_decode_fmri(handle,
+ "svc:/system/auditd:default/:properties/preselection/naflags",
+ NULL, NULL, NULL, NULL, property, 0);
+ if (ret == -1)
+ return -2;
+
+ value = scf_value_create(handle);
+ if (value == NULL)
+ return -2;
+
+ ret = scf_property_get_value(property, value);
+ if (ret == -1)
+ return -2;
+
+ ret = scf_value_get_astring(value, auditstring, len);
+ if (ret == -1)
+ return -2;
+
+ scf_value_destroy(value);
+ scf_property_destroy(property);
+ scf_handle_destroy(handle);
+
+ return 0;
+}
+#endif
+
+/*
+ * Check if the specified event is selected (enabled) for auditing.
+ * Returns 1 if the event is selected, 0 if not and -1 on failure.
+ */
+static int
+selected(char *username, uid_t uid, au_event_t event, int sf)
+{
+ int rc, sorf;
+ char naflags[512];
+ struct au_mask mask;
+
+ mask.am_success = mask.am_failure = 0;
+ if (uid < 0) {
+ /* get flags for non-attributable (to a real user) events */
+ rc = getacna(naflags, sizeof(naflags));
+ if (rc == 0)
+ (void) getauditflagsbin(naflags, &mask);
+ } else
+ rc = au_user_mask(username, &mask);
+
+ sorf = (sf == 0) ? AU_PRS_SUCCESS : AU_PRS_FAILURE;
+ return(au_preselect(event, &mask, sorf, AU_PRS_REREAD));
+}
+
+static void
+bsm_audit_record(int typ, char *string, au_event_t event_no)
+{
+ int ad, rc, sel;
+ uid_t uid = -1;
+ gid_t gid = -1;
+ pid_t pid = getpid();
+ AuditInfoTermID tid = ssh_bsm_tid;
+
+ if (the_authctxt != NULL && the_authctxt->valid) {
+ uid = the_authctxt->pw->pw_uid;
+ gid = the_authctxt->pw->pw_gid;
+ }
+
+ rc = (typ == 0) ? 0 : -1;
+ sel = selected(the_authctxt->user, uid, event_no, rc);
+ debug3("BSM audit: typ %d rc %d \"%s\"", typ, rc, string);
+ if (!sel)
+ return; /* audit event does not match mask, do not write */
+
+ debug3("BSM audit: writing audit new record");
+ ad = au_open();
+
+ (void) au_write(ad, AUToSubjectFunc(uid, uid, gid, uid, gid,
+ pid, pid, &tid));
+ (void) au_write(ad, au_to_text(string));
+ (void) au_write(ad, AUToReturnFunc(typ, rc));
+
+#ifdef BROKEN_BSM_API
+ /* The last argument is the event modifier flags. For
+ some seemingly undocumented reason it was added in
+ Solaris 11. */
+ rc = au_close(ad, AU_TO_WRITE, event_no, 0);
+#else
+ rc = au_close(ad, AU_TO_WRITE, event_no);
+#endif
+
+ if (rc < 0)
+ error("BSM audit: %s failed to write \"%s\" record: %s",
+ __func__, string, strerror(errno));
+}
+
+static void
+bsm_audit_session_setup(void)
+{
+ int rc;
+ struct AuditInfoStruct info;
+ au_mask_t mask;
+
+ if (the_authctxt == NULL) {
+ error("BSM audit: session setup internal error (NULL ctxt)");
+ return;
+ }
+
+ if (the_authctxt->valid)
+ info.ai_auid = the_authctxt->pw->pw_uid;
+ else
+ info.ai_auid = -1;
+ info.ai_asid = getpid();
+ mask.am_success = 0;
+ mask.am_failure = 0;
+
+ (void) au_user_mask(the_authctxt->user, &mask);
+
+ info.ai_mask.am_success = mask.am_success;
+ info.ai_mask.am_failure = mask.am_failure;
+
+ info.ai_termid = ssh_bsm_tid;
+
+ rc = SetAuditFunc(&info, sizeof(info));
+ if (rc < 0)
+ error("BSM audit: %s: %s failed: %s", __func__,
+ SetAuditFuncText, strerror(errno));
+}
+
+static void
+bsm_audit_bad_login(const char *what)
+{
+ char textbuf[BSM_TEXTBUFSZ];
+
+ if (the_authctxt->valid) {
+ (void) snprintf(textbuf, sizeof (textbuf),
+ gettext("invalid %s for user %s"),
+ what, the_authctxt->user);
+ bsm_audit_record(4, textbuf, AUE_openssh);
+ } else {
+ (void) snprintf(textbuf, sizeof (textbuf),
+ gettext("invalid user name \"%s\""),
+ the_authctxt->user);
+ bsm_audit_record(3, textbuf, AUE_openssh);
+ }
+}
+
+/* Below is the sshd audit API code */
+
+void
+audit_connection_from(const char *host, int port)
+{
+ AuditInfoTermID *tid = &ssh_bsm_tid;
+ char buf[1024];
+
+ if (cannot_audit(0))
+ return;
+ debug3("BSM audit: connection from %.100s port %d", host, port);
+
+ /* populate our terminal id structure */
+#if defined(HAVE_GETAUDIT_ADDR)
+ tid->at_port = (dev_t)port;
+ aug_get_machine((char *)host, &(tid->at_addr[0]), &(tid->at_type));
+ snprintf(buf, sizeof(buf), "%08x %08x %08x %08x", tid->at_addr[0],
+ tid->at_addr[1], tid->at_addr[2], tid->at_addr[3]);
+ debug3("BSM audit: iptype %d machine ID %s", (int)tid->at_type, buf);
+#else
+ /* this is used on IPv4-only machines */
+ tid->port = (dev_t)port;
+ tid->machine = inet_addr(host);
+ snprintf(buf, sizeof(buf), "%08x", tid->machine);
+ debug3("BSM audit: machine ID %s", buf);
+#endif
+}
+
+void
+audit_run_command(const char *command)
+{
+ /* not implemented */
+}
+
+void
+audit_session_open(struct logininfo *li)
+{
+ /* not implemented */
+}
+
+void
+audit_session_close(struct logininfo *li)
+{
+ /* 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))
+ return;
+
+ switch(event) {
+ case SSH_AUTH_SUCCESS:
+ logged_in = 1;
+ bsm_audit_session_setup();
+ snprintf(textbuf, sizeof(textbuf),
+ gettext("successful login %s"), user);
+ bsm_audit_record(0, textbuf, AUE_openssh);
+ break;
+
+ case SSH_CONNECTION_CLOSE:
+ /*
+ * We can also get a close event if the user attempted auth
+ * but never succeeded.
+ */
+ if (logged_in) {
+ snprintf(textbuf, sizeof(textbuf),
+ gettext("sshd logout %s"), the_authctxt->user);
+ bsm_audit_record(0, textbuf, AUE_logout);
+ } else {
+ debug("%s: connection closed without authentication",
+ __func__);
+ }
+ break;
+
+ case SSH_NOLOGIN:
+ bsm_audit_record(1,
+ gettext("logins disabled by /etc/nologin"), AUE_openssh);
+ break;
+
+ case SSH_LOGIN_EXCEED_MAXTRIES:
+ snprintf(textbuf, sizeof(textbuf),
+ gettext("too many tries for user %s"), the_authctxt->user);
+ bsm_audit_record(1, textbuf, AUE_openssh);
+ break;
+
+ case SSH_LOGIN_ROOT_DENIED:
+ bsm_audit_record(2, gettext("not_console"), AUE_openssh);
+ break;
+
+ case SSH_AUTH_FAIL_PASSWD:
+ bsm_audit_bad_login("password");
+ break;
+
+ case SSH_AUTH_FAIL_KBDINT:
+ bsm_audit_bad_login("interactive password entry");
+ break;
+
+ default:
+ debug("%s: unhandled event %d", __func__, event);
+ }
+}
+#endif /* BSM */