From 8fe079451161b6b478dc686f43d8fe455974b4f8 Mon Sep 17 00:00:00 2001 From: Darren Tucker Date: Sun, 20 Feb 2005 21:08:00 +1100 Subject: - (dtucker) [LICENCE Makefile.in README.platform audit-bsm.c configure.ac defines.h] Bug #125: Add *EXPERIMENTAL* BSM audit support. Configure --with-audit=bsm to enable. Patch originally from Sun Microsystems, parts by John R. Jackson. ok djm@ --- audit-bsm.c | 329 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 329 insertions(+) create mode 100644 audit-bsm.c (limited to 'audit-bsm.c') diff --git a/audit-bsm.c b/audit-bsm.c new file mode 100644 index 000000000..c2679d3da --- /dev/null +++ b/audit-bsm.c @@ -0,0 +1,329 @@ +/* $Id: audit-bsm.c,v 1.1 2005/02/20 10:08:00 dtucker Exp $ */ + +/* + * 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 "ssh.h" +#include "log.h" +#include "auth.h" +#include "xmalloc.h" + +#ifndef AUE_openssh +# define AUE_openssh 32800 +#endif +#include +#include +#include +#include +#include + +#if defined(HAVE_GETAUDIT_ADDR) +#define AuditInfoStruct auditinfo_addr +#define AuditInfoTermID au_tid_addr_t +#define GetAuditFunc(a,b) getaudit_addr((a),(b)) +#define GetAuditFuncText "getaudit_addr" +#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 GetAuditFunc(a,b) getaudit(a) +#define GetAuditFuncText "getaudit" +#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 + +extern int cannot_audit(int); +extern void aug_init(void); +extern dev_t aug_get_port(void); +extern int aug_get_machine(char *, u_int32_t *, u_int32_t *); +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; + +/* Below is the low-level BSM interface code */ + +/* + * 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)); + + rc = au_close(ad, AU_TO_WRITE, event_no); + 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(const char *ttyn) +{ + /* not implemented */ +} + +void +audit_session_close(const char *ttyn) +{ + /* 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 */ -- cgit v1.2.3