Damien Miller | ded319c | 2006-09-01 15:38:36 +1000 | [diff] [blame] | 1 | /* $Id: audit-bsm.c,v 1.4 2006/09/01 05:38:36 djm Exp $ */ |
Darren Tucker | 8fe0794 | 2005-02-20 21:08:00 +1100 | [diff] [blame] | 2 | |
| 3 | /* |
| 4 | * TODO |
| 5 | * |
| 6 | * - deal with overlap between this and sys_auth_allowed_user |
| 7 | * sys_auth_record_login and record_failed_login. |
| 8 | */ |
| 9 | |
| 10 | /* |
| 11 | * Copyright 1988-2002 Sun Microsystems, Inc. All rights reserved. |
| 12 | * Use is subject to license terms. |
| 13 | * |
| 14 | * Redistribution and use in source and binary forms, with or without |
| 15 | * modification, are permitted provided that the following conditions |
| 16 | * are met: |
| 17 | * 1. Redistributions of source code must retain the above copyright |
| 18 | * notice, this list of conditions and the following disclaimer. |
| 19 | * 2. Redistributions in binary form must reproduce the above copyright |
| 20 | * notice, this list of conditions and the following disclaimer in the |
| 21 | * documentation and/or other materials provided with the distribution. |
| 22 | * |
| 23 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 24 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 25 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 26 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 27 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 28 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 29 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 30 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 31 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 32 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 33 | * |
| 34 | */ |
| 35 | /* #pragma ident "@(#)bsmaudit.c 1.1 01/09/17 SMI" */ |
| 36 | |
| 37 | #include "includes.h" |
| 38 | #if defined(USE_BSM_AUDIT) |
| 39 | |
Damien Miller | 56799c3 | 2006-08-16 11:40:45 +1000 | [diff] [blame] | 40 | #include <sys/types.h> |
| 41 | |
Damien Miller | ded319c | 2006-09-01 15:38:36 +1000 | [diff] [blame] | 42 | #include <stdarg.h> |
Damien Miller | 56799c3 | 2006-08-16 11:40:45 +1000 | [diff] [blame] | 43 | #include <unistd.h> |
| 44 | |
Darren Tucker | 8fe0794 | 2005-02-20 21:08:00 +1100 | [diff] [blame] | 45 | #include "ssh.h" |
| 46 | #include "log.h" |
Darren Tucker | 3e71451 | 2006-08-06 00:12:54 +1000 | [diff] [blame] | 47 | #include "key.h" |
| 48 | #include "hostfile.h" |
Darren Tucker | 8fe0794 | 2005-02-20 21:08:00 +1100 | [diff] [blame] | 49 | #include "auth.h" |
| 50 | #include "xmalloc.h" |
| 51 | |
| 52 | #ifndef AUE_openssh |
| 53 | # define AUE_openssh 32800 |
| 54 | #endif |
| 55 | #include <bsm/audit.h> |
| 56 | #include <bsm/libbsm.h> |
| 57 | #include <bsm/audit_uevents.h> |
| 58 | #include <bsm/audit_record.h> |
| 59 | #include <locale.h> |
| 60 | |
| 61 | #if defined(HAVE_GETAUDIT_ADDR) |
| 62 | #define AuditInfoStruct auditinfo_addr |
| 63 | #define AuditInfoTermID au_tid_addr_t |
| 64 | #define GetAuditFunc(a,b) getaudit_addr((a),(b)) |
| 65 | #define GetAuditFuncText "getaudit_addr" |
| 66 | #define SetAuditFunc(a,b) setaudit_addr((a),(b)) |
| 67 | #define SetAuditFuncText "setaudit_addr" |
| 68 | #define AUToSubjectFunc au_to_subject_ex |
| 69 | #define AUToReturnFunc(a,b) au_to_return32((a), (int32_t)(b)) |
| 70 | #else |
| 71 | #define AuditInfoStruct auditinfo |
| 72 | #define AuditInfoTermID au_tid_t |
| 73 | #define GetAuditFunc(a,b) getaudit(a) |
| 74 | #define GetAuditFuncText "getaudit" |
| 75 | #define SetAuditFunc(a,b) setaudit(a) |
| 76 | #define SetAuditFuncText "setaudit" |
| 77 | #define AUToSubjectFunc au_to_subject |
| 78 | #define AUToReturnFunc(a,b) au_to_return((a), (u_int)(b)) |
| 79 | #endif |
| 80 | |
| 81 | extern int cannot_audit(int); |
| 82 | extern void aug_init(void); |
| 83 | extern dev_t aug_get_port(void); |
| 84 | extern int aug_get_machine(char *, u_int32_t *, u_int32_t *); |
| 85 | extern void aug_save_auid(au_id_t); |
| 86 | extern void aug_save_uid(uid_t); |
| 87 | extern void aug_save_euid(uid_t); |
| 88 | extern void aug_save_gid(gid_t); |
| 89 | extern void aug_save_egid(gid_t); |
| 90 | extern void aug_save_pid(pid_t); |
| 91 | extern void aug_save_asid(au_asid_t); |
| 92 | extern void aug_save_tid(dev_t, unsigned int); |
| 93 | extern void aug_save_tid_ex(dev_t, u_int32_t *, u_int32_t); |
| 94 | extern int aug_save_me(void); |
| 95 | extern int aug_save_namask(void); |
| 96 | extern void aug_save_event(au_event_t); |
| 97 | extern void aug_save_sorf(int); |
| 98 | extern void aug_save_text(char *); |
| 99 | extern void aug_save_text1(char *); |
| 100 | extern void aug_save_text2(char *); |
| 101 | extern void aug_save_na(int); |
| 102 | extern void aug_save_user(char *); |
| 103 | extern void aug_save_path(char *); |
| 104 | extern int aug_save_policy(void); |
| 105 | extern void aug_save_afunc(int (*)(int)); |
| 106 | extern int aug_audit(void); |
| 107 | extern int aug_na_selected(void); |
| 108 | extern int aug_selected(void); |
| 109 | extern int aug_daemon_session(void); |
| 110 | |
| 111 | #ifndef HAVE_GETTEXT |
| 112 | # define gettext(a) (a) |
| 113 | #endif |
| 114 | |
| 115 | extern Authctxt *the_authctxt; |
| 116 | static AuditInfoTermID ssh_bsm_tid; |
| 117 | |
| 118 | /* Below is the low-level BSM interface code */ |
| 119 | |
| 120 | /* |
| 121 | * Check if the specified event is selected (enabled) for auditing. |
| 122 | * Returns 1 if the event is selected, 0 if not and -1 on failure. |
| 123 | */ |
| 124 | static int |
| 125 | selected(char *username, uid_t uid, au_event_t event, int sf) |
| 126 | { |
| 127 | int rc, sorf; |
| 128 | char naflags[512]; |
| 129 | struct au_mask mask; |
| 130 | |
| 131 | mask.am_success = mask.am_failure = 0; |
| 132 | if (uid < 0) { |
| 133 | /* get flags for non-attributable (to a real user) events */ |
| 134 | rc = getacna(naflags, sizeof(naflags)); |
| 135 | if (rc == 0) |
| 136 | (void) getauditflagsbin(naflags, &mask); |
| 137 | } else |
| 138 | rc = au_user_mask(username, &mask); |
| 139 | |
| 140 | sorf = (sf == 0) ? AU_PRS_SUCCESS : AU_PRS_FAILURE; |
| 141 | return(au_preselect(event, &mask, sorf, AU_PRS_REREAD)); |
| 142 | } |
| 143 | |
| 144 | static void |
| 145 | bsm_audit_record(int typ, char *string, au_event_t event_no) |
| 146 | { |
| 147 | int ad, rc, sel; |
| 148 | uid_t uid = -1; |
| 149 | gid_t gid = -1; |
| 150 | pid_t pid = getpid(); |
| 151 | AuditInfoTermID tid = ssh_bsm_tid; |
| 152 | |
| 153 | if (the_authctxt != NULL && the_authctxt->valid) { |
| 154 | uid = the_authctxt->pw->pw_uid; |
| 155 | gid = the_authctxt->pw->pw_gid; |
| 156 | } |
| 157 | |
| 158 | rc = (typ == 0) ? 0 : -1; |
| 159 | sel = selected(the_authctxt->user, uid, event_no, rc); |
| 160 | debug3("BSM audit: typ %d rc %d \"%s\"", typ, rc, string); |
| 161 | if (!sel) |
| 162 | return; /* audit event does not match mask, do not write */ |
| 163 | |
| 164 | debug3("BSM audit: writing audit new record"); |
| 165 | ad = au_open(); |
| 166 | |
| 167 | (void) au_write(ad, AUToSubjectFunc(uid, uid, gid, uid, gid, |
| 168 | pid, pid, &tid)); |
| 169 | (void) au_write(ad, au_to_text(string)); |
| 170 | (void) au_write(ad, AUToReturnFunc(typ, rc)); |
| 171 | |
| 172 | rc = au_close(ad, AU_TO_WRITE, event_no); |
| 173 | if (rc < 0) |
| 174 | error("BSM audit: %s failed to write \"%s\" record: %s", |
| 175 | __func__, string, strerror(errno)); |
| 176 | } |
| 177 | |
| 178 | static void |
| 179 | bsm_audit_session_setup(void) |
| 180 | { |
| 181 | int rc; |
| 182 | struct AuditInfoStruct info; |
| 183 | au_mask_t mask; |
| 184 | |
| 185 | if (the_authctxt == NULL) { |
| 186 | error("BSM audit: session setup internal error (NULL ctxt)"); |
| 187 | return; |
| 188 | } |
| 189 | |
| 190 | if (the_authctxt->valid) |
| 191 | info.ai_auid = the_authctxt->pw->pw_uid; |
| 192 | else |
| 193 | info.ai_auid = -1; |
| 194 | info.ai_asid = getpid(); |
| 195 | mask.am_success = 0; |
| 196 | mask.am_failure = 0; |
| 197 | |
| 198 | (void) au_user_mask(the_authctxt->user, &mask); |
| 199 | |
| 200 | info.ai_mask.am_success = mask.am_success; |
| 201 | info.ai_mask.am_failure = mask.am_failure; |
| 202 | |
| 203 | info.ai_termid = ssh_bsm_tid; |
| 204 | |
| 205 | rc = SetAuditFunc(&info, sizeof(info)); |
| 206 | if (rc < 0) |
| 207 | error("BSM audit: %s: %s failed: %s", __func__, |
| 208 | SetAuditFuncText, strerror(errno)); |
| 209 | } |
| 210 | |
| 211 | static void |
| 212 | bsm_audit_bad_login(const char *what) |
| 213 | { |
| 214 | char textbuf[BSM_TEXTBUFSZ]; |
| 215 | |
| 216 | if (the_authctxt->valid) { |
| 217 | (void) snprintf(textbuf, sizeof (textbuf), |
| 218 | gettext("invalid %s for user %s"), |
| 219 | what, the_authctxt->user); |
| 220 | bsm_audit_record(4, textbuf, AUE_openssh); |
| 221 | } else { |
| 222 | (void) snprintf(textbuf, sizeof (textbuf), |
| 223 | gettext("invalid user name \"%s\""), |
| 224 | the_authctxt->user); |
| 225 | bsm_audit_record(3, textbuf, AUE_openssh); |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | /* Below is the sshd audit API code */ |
| 230 | |
| 231 | void |
| 232 | audit_connection_from(const char *host, int port) |
| 233 | { |
| 234 | AuditInfoTermID *tid = &ssh_bsm_tid; |
| 235 | char buf[1024]; |
| 236 | |
| 237 | if (cannot_audit(0)) |
| 238 | return; |
| 239 | debug3("BSM audit: connection from %.100s port %d", host, port); |
| 240 | |
| 241 | /* populate our terminal id structure */ |
| 242 | #if defined(HAVE_GETAUDIT_ADDR) |
| 243 | tid->at_port = (dev_t)port; |
| 244 | aug_get_machine((char *)host, &(tid->at_addr[0]), &(tid->at_type)); |
| 245 | snprintf(buf, sizeof(buf), "%08x %08x %08x %08x", tid->at_addr[0], |
| 246 | tid->at_addr[1], tid->at_addr[2], tid->at_addr[3]); |
| 247 | debug3("BSM audit: iptype %d machine ID %s", (int)tid->at_type, buf); |
| 248 | #else |
| 249 | /* this is used on IPv4-only machines */ |
| 250 | tid->port = (dev_t)port; |
| 251 | tid->machine = inet_addr(host); |
| 252 | snprintf(buf, sizeof(buf), "%08x", tid->machine); |
| 253 | debug3("BSM audit: machine ID %s", buf); |
| 254 | #endif |
| 255 | } |
| 256 | |
| 257 | void |
| 258 | audit_run_command(const char *command) |
| 259 | { |
| 260 | /* not implemented */ |
| 261 | } |
| 262 | |
| 263 | void |
| 264 | audit_session_open(const char *ttyn) |
| 265 | { |
| 266 | /* not implemented */ |
| 267 | } |
| 268 | |
| 269 | void |
| 270 | audit_session_close(const char *ttyn) |
| 271 | { |
| 272 | /* not implemented */ |
| 273 | } |
| 274 | |
| 275 | void |
| 276 | audit_event(ssh_audit_event_t event) |
| 277 | { |
| 278 | char textbuf[BSM_TEXTBUFSZ]; |
| 279 | static int logged_in = 0; |
| 280 | const char *user = the_authctxt ? the_authctxt->user : "(unknown user)"; |
| 281 | |
| 282 | if (cannot_audit(0)) |
| 283 | return; |
| 284 | |
| 285 | switch(event) { |
| 286 | case SSH_AUTH_SUCCESS: |
| 287 | logged_in = 1; |
| 288 | bsm_audit_session_setup(); |
| 289 | snprintf(textbuf, sizeof(textbuf), |
| 290 | gettext("successful login %s"), user); |
| 291 | bsm_audit_record(0, textbuf, AUE_openssh); |
| 292 | break; |
| 293 | |
| 294 | case SSH_CONNECTION_CLOSE: |
| 295 | /* |
| 296 | * We can also get a close event if the user attempted auth |
| 297 | * but never succeeded. |
| 298 | */ |
| 299 | if (logged_in) { |
| 300 | snprintf(textbuf, sizeof(textbuf), |
| 301 | gettext("sshd logout %s"), the_authctxt->user); |
| 302 | bsm_audit_record(0, textbuf, AUE_logout); |
| 303 | } else { |
| 304 | debug("%s: connection closed without authentication", |
| 305 | __func__); |
| 306 | } |
| 307 | break; |
| 308 | |
| 309 | case SSH_NOLOGIN: |
| 310 | bsm_audit_record(1, |
| 311 | gettext("logins disabled by /etc/nologin"), AUE_openssh); |
| 312 | break; |
| 313 | |
| 314 | case SSH_LOGIN_EXCEED_MAXTRIES: |
| 315 | snprintf(textbuf, sizeof(textbuf), |
| 316 | gettext("too many tries for user %s"), the_authctxt->user); |
| 317 | bsm_audit_record(1, textbuf, AUE_openssh); |
| 318 | break; |
| 319 | |
| 320 | case SSH_LOGIN_ROOT_DENIED: |
| 321 | bsm_audit_record(2, gettext("not_console"), AUE_openssh); |
| 322 | break; |
| 323 | |
| 324 | case SSH_AUTH_FAIL_PASSWD: |
| 325 | bsm_audit_bad_login("password"); |
| 326 | break; |
| 327 | |
| 328 | case SSH_AUTH_FAIL_KBDINT: |
| 329 | bsm_audit_bad_login("interactive password entry"); |
| 330 | break; |
| 331 | |
| 332 | default: |
| 333 | debug("%s: unhandled event %d", __func__, event); |
| 334 | } |
| 335 | } |
| 336 | #endif /* BSM */ |