utmpx.c revision 1.1
1 /* $NetBSD: utmpx.c,v 1.1 2002/02/22 20:11:44 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 #include <sys/cdefs.h> 39 40 #if defined(LIBC_SCCS) && !defined(lint) 41 __RCSID("$NetBSD: utmpx.c,v 1.1 2002/02/22 20:11:44 christos Exp $"); 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include <sys/types.h> 45 #include <sys/param.h> 46 #include <sys/wait.h> 47 #include <sys/socket.h> 48 #include <sys/time.h> 49 #include <sys/stat.h> 50 51 #include <stdio.h> 52 #include <string.h> 53 #include <vis.h> 54 #include <utmpx.h> 55 #include <unistd.h> 56 57 static FILE *fp; 58 static struct utmpx ut; 59 static char utfile[MAXPATHLEN] = _PATH_UTMPX; 60 61 static struct utmpx *utmp_update(const struct utmpx *); 62 63 static const char vers[] = "utmpx-1.00"; 64 65 void 66 setutxent() 67 { 68 (void)memset(&ut, 0, sizeof(ut)); 69 if (fp == NULL) 70 return; 71 (void)fseeko(fp, (off_t)sizeof(ut), SEEK_SET); 72 } 73 74 75 void 76 endutxent() 77 { 78 (void)memset(&ut, 0, sizeof(ut)); 79 if (fp != NULL) 80 (void)fclose(fp); 81 } 82 83 84 struct utmpx * 85 getutxent() 86 { 87 if (fp == NULL) { 88 struct stat st; 89 90 if ((fp = fopen(utfile, "r+")) == NULL) 91 if ((fp = fopen(utfile, "r")) == NULL) 92 goto fail; 93 94 /* get file size in order to check if new file */ 95 if (fstat(fileno(fp), &st) == -1) 96 goto failclose; 97 98 if (st.st_size == 0) { 99 /* new file, add signature record */ 100 (void)memset(&ut, 0, sizeof(ut)); 101 ut.ut_type = SIGNATURE; 102 (void)memcpy(ut.ut_name, vers, sizeof(vers)); 103 if (fwrite(&ut, sizeof(ut), 1, fp) != sizeof(ut)) 104 goto failclose; 105 } else { 106 /* old file, read signature record */ 107 if (fread(&ut, sizeof(ut), 1, fp) != sizeof(ut)) 108 goto failclose; 109 if (memcmp(ut.ut_name, vers, sizeof(vers)) != 0 || 110 ut.ut_type != SIGNATURE) 111 goto failclose; 112 } 113 } 114 115 if (fread(&ut, sizeof(ut), 1, fp) != sizeof(ut)) 116 goto fail; 117 118 return &ut; 119 failclose: 120 (void)fclose(fp); 121 fail: 122 (void)memset(&ut, 0, sizeof(ut)); 123 return NULL; 124 } 125 126 127 struct utmpx * 128 getutxid(const struct utmpx *utx) 129 { 130 if (utx->ut_type == EMPTY) 131 return NULL; 132 133 do { 134 if (ut.ut_type == EMPTY) 135 continue; 136 switch (utx->ut_type) { 137 case EMPTY: 138 return NULL; 139 case RUN_LVL: 140 case BOOT_TIME: 141 case OLD_TIME: 142 case NEW_TIME: 143 if (ut.ut_type == utx->ut_type) 144 return &ut; 145 break; 146 case INIT_PROCESS: 147 case LOGIN_PROCESS: 148 case USER_PROCESS: 149 case DEAD_PROCESS: 150 switch (ut.ut_type) { 151 case INIT_PROCESS: 152 case LOGIN_PROCESS: 153 case USER_PROCESS: 154 case DEAD_PROCESS: 155 if (memcmp(ut.ut_id, utx->ut_id, 156 sizeof(ut.ut_id)) == 0) 157 return &ut; 158 break; 159 default: 160 break; 161 } 162 break; 163 default: 164 return NULL; 165 } 166 } 167 while (getutxent() != NULL); 168 return NULL; 169 } 170 171 172 struct utmpx * 173 getutxline(const struct utmpx *utx) 174 { 175 do { 176 switch (ut.ut_type) { 177 case EMPTY: 178 break; 179 case LOGIN_PROCESS: 180 case USER_PROCESS: 181 if (strncmp(ut.ut_line, utx->ut_line, 182 sizeof(ut.ut_line)) == 0) 183 return &ut; 184 break; 185 default: 186 break; 187 } 188 } 189 while (getutxent() != NULL); 190 return NULL; 191 } 192 193 194 struct utmpx * 195 pututxline(const struct utmpx *utx) 196 { 197 struct utmpx temp, *u = NULL; 198 int gotlock = 0; 199 200 if (strcmp(_PATH_UTMPX, utfile) == 0 && geteuid() != 0) 201 return utmp_update(utx); 202 203 if (utx == NULL) 204 return NULL; 205 206 (void)memcpy(&temp, utx, sizeof(temp)); 207 208 if (fp == NULL) { 209 (void)getutxent(); 210 if (fp == NULL) 211 return NULL; 212 } 213 214 if (getutxid(&temp) == NULL) { 215 setutxent(); 216 if (getutxid(&temp) == NULL) { 217 if (lockf(fileno(fp), F_LOCK, (off_t)0) == -1) 218 return NULL; 219 gotlock++; 220 if (fseeko(fp, (off_t)0, SEEK_END) == -1) 221 goto fail; 222 } 223 } 224 225 if (!gotlock) { 226 /* we are not appending */ 227 if (fseeko(fp, -(off_t)sizeof(ut), SEEK_CUR) == -1) 228 return NULL; 229 } 230 231 if (fwrite(&temp, sizeof (temp), 1, fp) != 1) 232 goto fail; 233 234 if (fflush(fp) == -1) 235 goto fail; 236 237 u = memcpy(&ut, &temp, sizeof(ut)); 238 fail: 239 if (gotlock) { 240 if (lockf(fileno(fp), F_ULOCK, (off_t)0) == -1) 241 return NULL; 242 } 243 return u; 244 } 245 246 247 static struct utmpx * 248 utmp_update(const struct utmpx *utx) 249 { 250 char buf[sizeof(*utx) * 4 + 1]; 251 pid_t pid; 252 int status; 253 254 (void)strvisx(buf, (const char *)(const void *)utx, sizeof(*utx), 255 VIS_WHITE); 256 switch (pid = fork()) { 257 case 0: 258 (void)execl(_PATH_UTMP_UPDATE, 259 strrchr(_PATH_UTMP_UPDATE, '/') + 1, buf); 260 exit(1); 261 /*NOTREACHED*/ 262 case -1: 263 return NULL; 264 default: 265 if (waitpid(pid, &status, 0) == -1) 266 return NULL; 267 if (WIFEXITED(status) && WEXITSTATUS(status) == 0) 268 return memcpy(&ut, utx, sizeof(ut)); 269 return NULL; 270 } 271 272 } 273 274 275 /* 276 * The following are extensions and not part of the X/Open spec 277 */ 278 int 279 utmpxname(const char *fname) 280 { 281 size_t len = strlen(fname); 282 283 if (len >= sizeof(utfile)) 284 return 0; 285 286 /* must end in x! */ 287 if (fname[len - 1] != 'x') 288 return 0; 289 290 (void)strcpy(utfile, fname); 291 endutxent(); 292 return 1; 293 } 294
Indexes created Mon Sep 29 21:09:56 GMT 2025