1 /* $Id: audit-bsm.c,v 1.4 2006/09/01 05:38:36 djm Exp $ */ 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 40 #include <sys/types.h> 41 42 #include <stdarg.h> 43 #include <unistd.h> 44 45 #include "ssh.h" 46 #include "log.h" 47 #include "key.h" 48 #include "hostfile.h" 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 */ 337