1 /*- 2 * Copyright (c) 2010 Ed Schouten <ed@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "namespace.h" 31 #include <sys/endian.h> 32 #include <sys/param.h> 33 #include <sys/stat.h> 34 #include <errno.h> 35 #include <stdio.h> 36 #include <string.h> 37 #include <utmpx.h> 38 #include "utxdb.h" 39 #include "un-namespace.h" 40 41 #ifdef __NO_TLS 42 static FILE *uf = NULL; 43 static int udb; 44 #else 45 static _Thread_local FILE *uf = NULL; 46 static _Thread_local int udb; 47 #endif 48 49 int 50 setutxdb(int db, const char *file) 51 { 52 struct stat sb; 53 54 switch (db) { 55 case UTXDB_ACTIVE: 56 if (file == NULL) 57 file = _PATH_UTX_ACTIVE; 58 break; 59 case UTXDB_LASTLOGIN: 60 if (file == NULL) 61 file = _PATH_UTX_LASTLOGIN; 62 break; 63 case UTXDB_LOG: 64 if (file == NULL) 65 file = _PATH_UTX_LOG; 66 break; 67 default: 68 errno = EINVAL; 69 return (-1); 70 } 71 72 if (uf != NULL) 73 fclose(uf); 74 uf = fopen(file, "re"); 75 if (uf == NULL) 76 return (-1); 77 78 if (db != UTXDB_LOG) { 79 /* Safety check: never use broken files. */ 80 if (_fstat(fileno(uf), &sb) != -1 && 81 sb.st_size % sizeof(struct futx) != 0) { 82 fclose(uf); 83 uf = NULL; 84 errno = EFTYPE; 85 return (-1); 86 } 87 /* Prevent reading of partial records. */ 88 (void)setvbuf(uf, NULL, _IOFBF, 89 rounddown(BUFSIZ, sizeof(struct futx))); 90 } 91 92 udb = db; 93 return (0); 94 } 95 96 void 97 setutxent(void) 98 { 99 100 setutxdb(UTXDB_ACTIVE, NULL); 101 } 102 103 void 104 endutxent(void) 105 { 106 107 if (uf != NULL) { 108 fclose(uf); 109 uf = NULL; 110 } 111 } 112 113 static int 114 getfutxent(struct futx *fu) 115 { 116 117 if (uf == NULL) 118 setutxent(); 119 if (uf == NULL) 120 return (-1); 121 122 if (udb == UTXDB_LOG) { 123 uint16_t len; 124 125 retry: 126 if (fread(&len, sizeof(len), 1, uf) != 1) 127 return (-1); 128 len = be16toh(len); 129 if (len == 0) { 130 /* 131 * XXX: Though zero-size records are valid in theory, 132 * they can never occur in practice. Zero-size records 133 * indicate file corruption. Seek one byte forward, to 134 * see if we can find a record there. 135 */ 136 ungetc('\0', uf); 137 goto retry; 138 } 139 if (len > sizeof *fu) { 140 /* Forward compatibility. */ 141 if (fread(fu, sizeof(*fu), 1, uf) != 1) 142 return (-1); 143 fseek(uf, len - sizeof(*fu), SEEK_CUR); 144 } else { 145 /* Partial record. */ 146 memset(fu, 0, sizeof(*fu)); 147 if (fread(fu, len, 1, uf) != 1) 148 return (-1); 149 } 150 } else { 151 if (fread(fu, sizeof(*fu), 1, uf) != 1) 152 return (-1); 153 } 154 return (0); 155 } 156 157 struct utmpx * 158 getutxent(void) 159 { 160 struct futx fu; 161 162 if (getfutxent(&fu) != 0) 163 return (NULL); 164 return (futx_to_utx(&fu)); 165 } 166 167 struct utmpx * 168 getutxid(const struct utmpx *id) 169 { 170 struct futx fu; 171 172 for (;;) { 173 if (getfutxent(&fu) != 0) 174 return (NULL); 175 176 switch (fu.fu_type) { 177 case USER_PROCESS: 178 case INIT_PROCESS: 179 case LOGIN_PROCESS: 180 case DEAD_PROCESS: 181 switch (id->ut_type) { 182 case USER_PROCESS: 183 case INIT_PROCESS: 184 case LOGIN_PROCESS: 185 case DEAD_PROCESS: 186 if (memcmp(fu.fu_id, id->ut_id, 187 MIN(sizeof(fu.fu_id), sizeof(id->ut_id))) == 188 0) 189 goto found; 190 } 191 break; 192 default: 193 if (fu.fu_type == id->ut_type) 194 goto found; 195 break; 196 } 197 } 198 199 found: 200 return (futx_to_utx(&fu)); 201 } 202 203 struct utmpx * 204 getutxline(const struct utmpx *line) 205 { 206 struct futx fu; 207 208 for (;;) { 209 if (getfutxent(&fu) != 0) 210 return (NULL); 211 212 switch (fu.fu_type) { 213 case USER_PROCESS: 214 case LOGIN_PROCESS: 215 if (strncmp(fu.fu_line, line->ut_line, 216 MIN(sizeof(fu.fu_line), sizeof(line->ut_line))) == 217 0) 218 goto found; 219 break; 220 } 221 } 222 223 found: 224 return (futx_to_utx(&fu)); 225 } 226 227 struct utmpx * 228 getutxuser(const char *user) 229 { 230 struct futx fu; 231 232 for (;;) { 233 if (getfutxent(&fu) != 0) 234 return (NULL); 235 236 switch (fu.fu_type) { 237 case USER_PROCESS: 238 if (strncmp(fu.fu_user, user, sizeof(fu.fu_user)) == 0) 239 goto found; 240 break; 241 } 242 } 243 244 found: 245 return (futx_to_utx(&fu)); 246 } 247