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 #include <sys/cdefs.h> 33 __SCCSID("@(#)pw_scan.c 8.3 (Berkeley) 4/2/94"); 34 __FBSDID("$FreeBSD$"); 35 36 /* 37 * This module is used to "verify" password entries by chpass(1) and 38 * pwd_mkdb(8). 39 */ 40 41 #include <sys/param.h> 42 43 #include <err.h> 44 #include <errno.h> 45 #include <pwd.h> 46 #include <string.h> 47 #include <stdlib.h> 48 #include <unistd.h> 49 50 #include "pw_scan.h" 51 52 /* 53 * Some software assumes that IDs are short. We should emit warnings 54 * for id's which cannot be stored in a short, but we are more liberal 55 * by default, warning for IDs greater than USHRT_MAX. 56 * 57 * If pw_big_ids_warning is -1 on entry to pw_scan(), it will be set based 58 * on the existence of PW_SCAN_BIG_IDS in the environment. 59 * 60 * It is believed all baseline system software that can not handle the 61 * normal ID sizes is now gone so pw_big_ids_warning is disabled for now. 62 * But the code has been left in place in case end-users want to re-enable 63 * it and/or for the next time the ID sizes get bigger but pieces of the 64 * system lag behind. 65 */ 66 static int pw_big_ids_warning = 0; 67 68 int 69 __pw_scan(char *bp, struct passwd *pw, int flags) 70 { 71 uid_t id; 72 int root; 73 char *ep, *p, *sh; 74 unsigned long temp; 75 76 if (pw_big_ids_warning == -1) 77 pw_big_ids_warning = getenv("PW_SCAN_BIG_IDS") == NULL ? 1 : 0; 78 79 pw->pw_fields = 0; 80 if (!(pw->pw_name = strsep(&bp, ":"))) /* login */ 81 goto fmt; 82 root = !strcmp(pw->pw_name, "root"); 83 if (pw->pw_name[0] && (pw->pw_name[0] != '+' || pw->pw_name[1] == '\0')) 84 pw->pw_fields |= _PWF_NAME; 85 86 if (!(pw->pw_passwd = strsep(&bp, ":"))) /* passwd */ 87 goto fmt; 88 if (pw->pw_passwd[0]) 89 pw->pw_fields |= _PWF_PASSWD; 90 91 if (!(p = strsep(&bp, ":"))) /* uid */ 92 goto fmt; 93 if (p[0]) 94 pw->pw_fields |= _PWF_UID; 95 else { 96 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') { 97 if (flags & _PWSCAN_WARN) 98 warnx("no uid for user %s", pw->pw_name); 99 return (0); 100 } 101 } 102 errno = 0; 103 temp = strtoul(p, &ep, 10); 104 if ((temp == ULONG_MAX && errno == ERANGE) || temp > UID_MAX) { 105 if (flags & _PWSCAN_WARN) 106 warnx("%s > max uid value (%u)", p, UID_MAX); 107 return (0); 108 } 109 id = temp; 110 if (*ep != '\0') { 111 if (flags & _PWSCAN_WARN) 112 warnx("%s uid is incorrect", p); 113 return (0); 114 } 115 if (root && id) { 116 if (flags & _PWSCAN_WARN) 117 warnx("root uid should be 0"); 118 return (0); 119 } 120 if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) { 121 warnx("%s > recommended max uid value (%u)", p, USHRT_MAX); 122 /*return (0);*/ /* THIS SHOULD NOT BE FATAL! */ 123 } 124 pw->pw_uid = id; 125 126 if (!(p = strsep(&bp, ":"))) /* gid */ 127 goto fmt; 128 if (p[0]) 129 pw->pw_fields |= _PWF_GID; 130 else { 131 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') { 132 if (flags & _PWSCAN_WARN) 133 warnx("no gid for user %s", pw->pw_name); 134 return (0); 135 } 136 } 137 errno = 0; 138 temp = strtoul(p, &ep, 10); 139 if ((temp == ULONG_MAX && errno == ERANGE) || temp > GID_MAX) { 140 if (flags & _PWSCAN_WARN) 141 warnx("%s > max gid value (%u)", p, GID_MAX); 142 return (0); 143 } 144 id = temp; 145 if (*ep != '\0') { 146 if (flags & _PWSCAN_WARN) 147 warnx("%s gid is incorrect", p); 148 return (0); 149 } 150 if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) { 151 warnx("%s > recommended max gid value (%u)", p, USHRT_MAX); 152 /* return (0); This should not be fatal! */ 153 } 154 pw->pw_gid = id; 155 156 if (flags & _PWSCAN_MASTER ) { 157 if (!(pw->pw_class = strsep(&bp, ":"))) /* class */ 158 goto fmt; 159 if (pw->pw_class[0]) 160 pw->pw_fields |= _PWF_CLASS; 161 162 if (!(p = strsep(&bp, ":"))) /* change */ 163 goto fmt; 164 if (p[0]) 165 pw->pw_fields |= _PWF_CHANGE; 166 pw->pw_change = atol(p); 167 168 if (!(p = strsep(&bp, ":"))) /* expire */ 169 goto fmt; 170 if (p[0]) 171 pw->pw_fields |= _PWF_EXPIRE; 172 pw->pw_expire = atol(p); 173 } 174 if (!(pw->pw_gecos = strsep(&bp, ":"))) /* gecos */ 175 goto fmt; 176 if (pw->pw_gecos[0]) 177 pw->pw_fields |= _PWF_GECOS; 178 179 if (!(pw->pw_dir = strsep(&bp, ":"))) /* directory */ 180 goto fmt; 181 if (pw->pw_dir[0]) 182 pw->pw_fields |= _PWF_DIR; 183 184 if (!(pw->pw_shell = strsep(&bp, ":"))) /* shell */ 185 goto fmt; 186 187 p = pw->pw_shell; 188 if (root && *p) { /* empty == /bin/sh */ 189 for (setusershell();;) { 190 if (!(sh = getusershell())) { 191 if (flags & _PWSCAN_WARN) 192 warnx("warning, unknown root shell"); 193 break; 194 } 195 if (!strcmp(p, sh)) 196 break; 197 } 198 endusershell(); 199 } 200 if (p[0]) 201 pw->pw_fields |= _PWF_SHELL; 202 203 if ((p = strsep(&bp, ":"))) { /* too many */ 204 fmt: 205 if (flags & _PWSCAN_WARN) 206 warnx("corrupted entry"); 207 return (0); 208 } 209 return (1); 210 } 211