1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #if defined(LIBC_SCCS) && !defined(lint) 33 static char sccsid[] = "@(#)pw_scan.c 8.3 (Berkeley) 4/2/94"; 34 #endif /* LIBC_SCCS and not lint */ 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 /* 39 * This module is used to "verify" password entries by chpass(1) and 40 * pwd_mkdb(8). 41 */ 42 43 #include <sys/param.h> 44 45 #include <err.h> 46 #include <errno.h> 47 #include <fcntl.h> 48 #include <pwd.h> 49 #include <stdio.h> 50 #include <string.h> 51 #include <stdlib.h> 52 #include <unistd.h> 53 54 #include "pw_scan.h" 55 56 /* 57 * Some software assumes that IDs are short. We should emit warnings 58 * for id's which cannot be stored in a short, but we are more liberal 59 * by default, warning for IDs greater than USHRT_MAX. 60 * 61 * If pw_big_ids_warning is -1 on entry to pw_scan(), it will be set based 62 * on the existence of PW_SCAN_BIG_IDS in the environment. 63 * 64 * It is believed all baseline system software that can not handle the 65 * normal ID sizes is now gone so pw_big_ids_warning is disabled for now. 66 * But the code has been left in place in case end-users want to re-enable 67 * it and/or for the next time the ID sizes get bigger but pieces of the 68 * system lag behind. 69 */ 70 static int pw_big_ids_warning = 0; 71 72 int 73 __pw_scan(char *bp, struct passwd *pw, int flags) 74 { 75 uid_t id; 76 int root; 77 char *ep, *p, *sh; 78 unsigned long temp; 79 80 if (pw_big_ids_warning == -1) 81 pw_big_ids_warning = getenv("PW_SCAN_BIG_IDS") == NULL ? 1 : 0; 82 83 pw->pw_fields = 0; 84 if (!(pw->pw_name = strsep(&bp, ":"))) /* login */ 85 goto fmt; 86 root = !strcmp(pw->pw_name, "root"); 87 if (pw->pw_name[0] && (pw->pw_name[0] != '+' || pw->pw_name[1] == '\0')) 88 pw->pw_fields |= _PWF_NAME; 89 90 if (!(pw->pw_passwd = strsep(&bp, ":"))) /* passwd */ 91 goto fmt; 92 if (pw->pw_passwd[0]) 93 pw->pw_fields |= _PWF_PASSWD; 94 95 if (!(p = strsep(&bp, ":"))) /* uid */ 96 goto fmt; 97 if (p[0]) 98 pw->pw_fields |= _PWF_UID; 99 else { 100 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') { 101 if (flags & _PWSCAN_WARN) 102 warnx("no uid for user %s", pw->pw_name); 103 return (0); 104 } 105 } 106 errno = 0; 107 temp = strtoul(p, &ep, 10); 108 if ((temp == ULONG_MAX && errno == ERANGE) || temp > UID_MAX) { 109 if (flags & _PWSCAN_WARN) 110 warnx("%s > max uid value (%u)", p, UID_MAX); 111 return (0); 112 } 113 id = temp; 114 if (*ep != '\0') { 115 if (flags & _PWSCAN_WARN) 116 warnx("%s uid is incorrect", p); 117 return (0); 118 } 119 if (root && id) { 120 if (flags & _PWSCAN_WARN) 121 warnx("root uid should be 0"); 122 return (0); 123 } 124 if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) { 125 warnx("%s > recommended max uid value (%u)", p, USHRT_MAX); 126 /*return (0);*/ /* THIS SHOULD NOT BE FATAL! */ 127 } 128 pw->pw_uid = id; 129 130 if (!(p = strsep(&bp, ":"))) /* gid */ 131 goto fmt; 132 if (p[0]) 133 pw->pw_fields |= _PWF_GID; 134 else { 135 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') { 136 if (flags & _PWSCAN_WARN) 137 warnx("no gid for user %s", pw->pw_name); 138 return (0); 139 } 140 } 141 errno = 0; 142 temp = strtoul(p, &ep, 10); 143 if ((temp == ULONG_MAX && errno == ERANGE) || temp > GID_MAX) { 144 if (flags & _PWSCAN_WARN) 145 warnx("%s > max gid value (%u)", p, GID_MAX); 146 return (0); 147 } 148 id = temp; 149 if (*ep != '\0') { 150 if (flags & _PWSCAN_WARN) 151 warnx("%s gid is incorrect", p); 152 return (0); 153 } 154 if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) { 155 warnx("%s > recommended max gid value (%u)", p, USHRT_MAX); 156 /* return (0); This should not be fatal! */ 157 } 158 pw->pw_gid = id; 159 160 if (flags & _PWSCAN_MASTER ) { 161 if (!(pw->pw_class = strsep(&bp, ":"))) /* class */ 162 goto fmt; 163 if (pw->pw_class[0]) 164 pw->pw_fields |= _PWF_CLASS; 165 166 if (!(p = strsep(&bp, ":"))) /* change */ 167 goto fmt; 168 if (p[0]) 169 pw->pw_fields |= _PWF_CHANGE; 170 pw->pw_change = atol(p); 171 172 if (!(p = strsep(&bp, ":"))) /* expire */ 173 goto fmt; 174 if (p[0]) 175 pw->pw_fields |= _PWF_EXPIRE; 176 pw->pw_expire = atol(p); 177 } 178 if (!(pw->pw_gecos = strsep(&bp, ":"))) /* gecos */ 179 goto fmt; 180 if (pw->pw_gecos[0]) 181 pw->pw_fields |= _PWF_GECOS; 182 183 if (!(pw->pw_dir = strsep(&bp, ":"))) /* directory */ 184 goto fmt; 185 if (pw->pw_dir[0]) 186 pw->pw_fields |= _PWF_DIR; 187 188 if (!(pw->pw_shell = strsep(&bp, ":"))) /* shell */ 189 goto fmt; 190 191 p = pw->pw_shell; 192 if (root && *p) { /* empty == /bin/sh */ 193 for (setusershell();;) { 194 if (!(sh = getusershell())) { 195 if (flags & _PWSCAN_WARN) 196 warnx("warning, unknown root shell"); 197 break; 198 } 199 if (!strcmp(p, sh)) 200 break; 201 } 202 endusershell(); 203 } 204 if (p[0]) 205 pw->pw_fields |= _PWF_SHELL; 206 207 if ((p = strsep(&bp, ":"))) { /* too many */ 208 fmt: 209 if (flags & _PWSCAN_WARN) 210 warnx("corrupted entry"); 211 return (0); 212 } 213 return (1); 214 } 215