1 /* $Id: audit-bsm.c,v 1.1 2005/02/20 10:08:00 dtucker 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 "ssh.h" 41 #include "log.h" 42 #include "auth.h" 43 #include "xmalloc.h" 44 45 #ifndef AUE_openssh 46 # define AUE_openssh 32800 47 #endif 48 #include <bsm/audit.h> 49 #include <bsm/libbsm.h> 50 #include <bsm/audit_uevents.h> 51 #include <bsm/audit_record.h> 52 #include <locale.h> 53 54 #if defined(HAVE_GETAUDIT_ADDR) 55 #define AuditInfoStruct auditinfo_addr 56 #define AuditInfoTermID au_tid_addr_t 57 #define GetAuditFunc(a,b) getaudit_addr((a),(b)) 58 #define GetAuditFuncText "getaudit_addr" 59 #define SetAuditFunc(a,b) setaudit_addr((a),(b)) 60 #define SetAuditFuncText "setaudit_addr" 61 #define AUToSubjectFunc au_to_subject_ex 62 #define AUToReturnFunc(a,b) au_to_return32((a), (int32_t)(b)) 63 #else 64 #define AuditInfoStruct auditinfo 65 #define AuditInfoTermID au_tid_t 66 #define GetAuditFunc(a,b) getaudit(a) 67 #define GetAuditFuncText "getaudit" 68 #define SetAuditFunc(a,b) setaudit(a) 69 #define SetAuditFuncText "setaudit" 70 #define AUToSubjectFunc au_to_subject 71 #define AUToReturnFunc(a,b) au_to_return((a), (u_int)(b)) 72 #endif 73 74 extern int cannot_audit(int); 75 extern void aug_init(void); 76 extern dev_t aug_get_port(void); 77 extern int aug_get_machine(char *, u_int32_t *, u_int32_t *); 78 extern void aug_save_auid(au_id_t); 79 extern void aug_save_uid(uid_t); 80 extern void aug_save_euid(uid_t); 81 extern void aug_save_gid(gid_t); 82 extern void aug_save_egid(gid_t); 83 extern void aug_save_pid(pid_t); 84 extern void aug_save_asid(au_asid_t); 85 extern void aug_save_tid(dev_t, unsigned int); 86 extern void aug_save_tid_ex(dev_t, u_int32_t *, u_int32_t); 87 extern int aug_save_me(void); 88 extern int aug_save_namask(void); 89 extern void aug_save_event(au_event_t); 90 extern void aug_save_sorf(int); 91 extern void aug_save_text(char *); 92 extern void aug_save_text1(char *); 93 extern void aug_save_text2(char *); 94 extern void aug_save_na(int); 95 extern void aug_save_user(char *); 96 extern void aug_save_path(char *); 97 extern int aug_save_policy(void); 98 extern void aug_save_afunc(int (*)(int)); 99 extern int aug_audit(void); 100 extern int aug_na_selected(void); 101 extern int aug_selected(void); 102 extern int aug_daemon_session(void); 103 104 #ifndef HAVE_GETTEXT 105 # define gettext(a) (a) 106 #endif 107 108 extern Authctxt *the_authctxt; 109 static AuditInfoTermID ssh_bsm_tid; 110 111 /* Below is the low-level BSM interface code */ 112 113 /* 114 * Check if the specified event is selected (enabled) for auditing. 115 * Returns 1 if the event is selected, 0 if not and -1 on failure. 116 */ 117 static int 118 selected(char *username, uid_t uid, au_event_t event, int sf) 119 { 120 int rc, sorf; 121 char naflags[512]; 122 struct au_mask mask; 123 124 mask.am_success = mask.am_failure = 0; 125 if (uid < 0) { 126 /* get flags for non-attributable (to a real user) events */ 127 rc = getacna(naflags, sizeof(naflags)); 128 if (rc == 0) 129 (void) getauditflagsbin(naflags, &mask); 130 } else 131 rc = au_user_mask(username, &mask); 132 133 sorf = (sf == 0) ? AU_PRS_SUCCESS : AU_PRS_FAILURE; 134 return(au_preselect(event, &mask, sorf, AU_PRS_REREAD)); 135 } 136 137 static void 138 bsm_audit_record(int typ, char *string, au_event_t event_no) 139 { 140 int ad, rc, sel; 141 uid_t uid = -1; 142 gid_t gid = -1; 143 pid_t pid = getpid(); 144 AuditInfoTermID tid = ssh_bsm_tid; 145 146 if (the_authctxt != NULL && the_authctxt->valid) { 147 uid = the_authctxt->pw->pw_uid; 148 gid = the_authctxt->pw->pw_gid; 149 } 150 151 rc = (typ == 0) ? 0 : -1; 152 sel = selected(the_authctxt->user, uid, event_no, rc); 153 debug3("BSM audit: typ %d rc %d \"%s\"", typ, rc, string); 154 if (!sel) 155 return; /* audit event does not match mask, do not write */ 156 157 debug3("BSM audit: writing audit new record"); 158 ad = au_open(); 159 160 (void) au_write(ad, AUToSubjectFunc(uid, uid, gid, uid, gid, 161 pid, pid, &tid)); 162 (void) au_write(ad, au_to_text(string)); 163 (void) au_write(ad, AUToReturnFunc(typ, rc)); 164 165 rc = au_close(ad, AU_TO_WRITE, event_no); 166 if (rc < 0) 167 error("BSM audit: %s failed to write \"%s\" record: %s", 168 __func__, string, strerror(errno)); 169 } 170 171 static void 172 bsm_audit_session_setup(void) 173 { 174 int rc; 175 struct AuditInfoStruct info; 176 au_mask_t mask; 177 178 if (the_authctxt == NULL) { 179 error("BSM audit: session setup internal error (NULL ctxt)"); 180 return; 181 } 182 183 if (the_authctxt->valid) 184 info.ai_auid = the_authctxt->pw->pw_uid; 185 else 186 info.ai_auid = -1; 187 info.ai_asid = getpid(); 188 mask.am_success = 0; 189 mask.am_failure = 0; 190 191 (void) au_user_mask(the_authctxt->user, &mask); 192 193 info.ai_mask.am_success = mask.am_success; 194 info.ai_mask.am_failure = mask.am_failure; 195 196 info.ai_termid = ssh_bsm_tid; 197 198 rc = SetAuditFunc(&info, sizeof(info)); 199 if (rc < 0) 200 error("BSM audit: %s: %s failed: %s", __func__, 201 SetAuditFuncText, strerror(errno)); 202 } 203 204 static void 205 bsm_audit_bad_login(const char *what) 206 { 207 char textbuf[BSM_TEXTBUFSZ]; 208 209 if (the_authctxt->valid) { 210 (void) snprintf(textbuf, sizeof (textbuf), 211 gettext("invalid %s for user %s"), 212 what, the_authctxt->user); 213 bsm_audit_record(4, textbuf, AUE_openssh); 214 } else { 215 (void) snprintf(textbuf, sizeof (textbuf), 216 gettext("invalid user name \"%s\""), 217 the_authctxt->user); 218 bsm_audit_record(3, textbuf, AUE_openssh); 219 } 220 } 221 222 /* Below is the sshd audit API code */ 223 224 void 225 audit_connection_from(const char *host, int port) 226 { 227 AuditInfoTermID *tid = &ssh_bsm_tid; 228 char buf[1024]; 229 230 if (cannot_audit(0)) 231 return; 232 debug3("BSM audit: connection from %.100s port %d", host, port); 233 234 /* populate our terminal id structure */ 235 #if defined(HAVE_GETAUDIT_ADDR) 236 tid->at_port = (dev_t)port; 237 aug_get_machine((char *)host, &(tid->at_addr[0]), &(tid->at_type)); 238 snprintf(buf, sizeof(buf), "%08x %08x %08x %08x", tid->at_addr[0], 239 tid->at_addr[1], tid->at_addr[2], tid->at_addr[3]); 240 debug3("BSM audit: iptype %d machine ID %s", (int)tid->at_type, buf); 241 #else 242 /* this is used on IPv4-only machines */ 243 tid->port = (dev_t)port; 244 tid->machine = inet_addr(host); 245 snprintf(buf, sizeof(buf), "%08x", tid->machine); 246 debug3("BSM audit: machine ID %s", buf); 247 #endif 248 } 249 250 void 251 audit_run_command(const char *command) 252 { 253 /* not implemented */ 254 } 255 256 void 257 audit_session_open(const char *ttyn) 258 { 259 /* not implemented */ 260 } 261 262 void 263 audit_session_close(const char *ttyn) 264 { 265 /* not implemented */ 266 } 267 268 void 269 audit_event(ssh_audit_event_t event) 270 { 271 char textbuf[BSM_TEXTBUFSZ]; 272 static int logged_in = 0; 273 const char *user = the_authctxt ? the_authctxt->user : "(unknown user)"; 274 275 if (cannot_audit(0)) 276 return; 277 278 switch(event) { 279 case SSH_AUTH_SUCCESS: 280 logged_in = 1; 281 bsm_audit_session_setup(); 282 snprintf(textbuf, sizeof(textbuf), 283 gettext("successful login %s"), user); 284 bsm_audit_record(0, textbuf, AUE_openssh); 285 break; 286 287 case SSH_CONNECTION_CLOSE: 288 /* 289 * We can also get a close event if the user attempted auth 290 * but never succeeded. 291 */ 292 if (logged_in) { 293 snprintf(textbuf, sizeof(textbuf), 294 gettext("sshd logout %s"), the_authctxt->user); 295 bsm_audit_record(0, textbuf, AUE_logout); 296 } else { 297 debug("%s: connection closed without authentication", 298 __func__); 299 } 300 break; 301 302 case SSH_NOLOGIN: 303 bsm_audit_record(1, 304 gettext("logins disabled by /etc/nologin"), AUE_openssh); 305 break; 306 307 case SSH_LOGIN_EXCEED_MAXTRIES: 308 snprintf(textbuf, sizeof(textbuf), 309 gettext("too many tries for user %s"), the_authctxt->user); 310 bsm_audit_record(1, textbuf, AUE_openssh); 311 break; 312 313 case SSH_LOGIN_ROOT_DENIED: 314 bsm_audit_record(2, gettext("not_console"), AUE_openssh); 315 break; 316 317 case SSH_AUTH_FAIL_PASSWD: 318 bsm_audit_bad_login("password"); 319 break; 320 321 case SSH_AUTH_FAIL_KBDINT: 322 bsm_audit_bad_login("interactive password entry"); 323 break; 324 325 default: 326 debug("%s: unhandled event %d", __func__, event); 327 } 328 } 329 #endif /* BSM */ 330