diff options
Diffstat (limited to 'lib/libc/gen/getpwent.c')
-rw-r--r-- | lib/libc/gen/getpwent.c | 775 |
1 files changed, 775 insertions, 0 deletions
diff --git a/lib/libc/gen/getpwent.c b/lib/libc/gen/getpwent.c new file mode 100644 index 0000000..6dfd1ed --- /dev/null +++ b/lib/libc/gen/getpwent.c @@ -0,0 +1,775 @@ +/* + * Copyright (c) 1988, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)getpwent.c 8.1 (Berkeley) 6/4/93"; +#endif /* LIBC_SCCS and not lint */ + +#include <stdio.h> +#include <sys/param.h> +#include <fcntl.h> +#include <db.h> +#include <syslog.h> +#include <pwd.h> +#include <utmp.h> +#include <errno.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <limits.h> +#include <grp.h> + +static struct passwd _pw_passwd; /* password structure */ +static DB *_pw_db; /* password database */ +static int _pw_keynum; /* key counter */ +static int _pw_stayopen; /* keep fd's open */ +#ifdef YP +#include <rpc/rpc.h> +#include <rpcsvc/yp_prot.h> +#include <rpcsvc/ypclnt.h> +struct _namelist { + char *name; + struct _namelist *next; +}; +static struct passwd _pw_copy; +struct _pw_cache { + struct passwd pw_entry; + struct _namelist *namelist; + struct _pw_cache *next; +}; +static int _pluscnt, _minuscnt; +static struct _pw_cache *_plushead = NULL, *_minushead = NULL; +static void _createcaches(), _freecaches(); +static int _scancaches(char *); +static int _yp_enabled; /* set true when yp enabled */ +static int _pw_stepping_yp; /* set true when stepping thru map */ +static int _yp_done; +static int _gotmaster; +static char *_pw_yp_domain; +static int _havemaster(char *); +static int _getyppass(struct passwd *, const char *, const char *); +static int _nextyppass(struct passwd *); +#endif +static int __hashpw(), __initdb(); + +struct passwd * +getpwent() +{ + DBT key; + char bf[sizeof(_pw_keynum) + 1]; + int rv; + + if (!_pw_db && !__initdb()) + return((struct passwd *)NULL); + +#ifdef YP + if(_pw_stepping_yp) { + _pw_passwd = _pw_copy; + if (_nextyppass(&_pw_passwd)) + return (&_pw_passwd); + else + _yp_done = 1; + } +#endif +tryagain: + + ++_pw_keynum; + bf[0] = _PW_KEYBYNUM; + bcopy((char *)&_pw_keynum, bf + 1, sizeof(_pw_keynum)); + key.data = (u_char *)bf; + key.size = sizeof(_pw_keynum) + 1; + rv = __hashpw(&key); + if(!rv) return (struct passwd *)NULL; +#ifdef YP + if(_pw_passwd.pw_name[0] == '+' || _pw_passwd.pw_name[0] == '-') { + _pw_copy = _pw_passwd; + if (_yp_done || !_nextyppass(&_pw_passwd)) + goto tryagain; + else + return (&_pw_passwd); + } +#else + /* Ignore YP password file entries when YP is disabled. */ + if(_pw_passwd.pw_name[0] == '+' || _pw_passwd.pw_name[0] == '-') { + goto tryagain; + } +#endif + return(&_pw_passwd); +} + +struct passwd * +getpwnam(name) + const char *name; +{ + DBT key; + int len, rval; + char bf[UT_NAMESIZE + 2]; + + if (!_pw_db && !__initdb()) + return((struct passwd *)NULL); + + bf[0] = _PW_KEYBYNAME; + len = strlen(name); + bcopy(name, bf + 1, MIN(len, UT_NAMESIZE)); + key.data = (u_char *)bf; + key.size = len + 1; + rval = __hashpw(&key); + +#ifdef YP + if (!rval && _yp_enabled) + rval = _getyppass(&_pw_passwd, name, "passwd.byname"); +#endif + /* + * Prevent login attempts when YP is not enabled but YP entries + * are in /etc/master.passwd. + */ + if (rval && (_pw_passwd.pw_name[0] == '+'|| + _pw_passwd.pw_name[0] == '-')) rval = 0; + + endpwent(); + return(rval ? &_pw_passwd : (struct passwd *)NULL); +} + +struct passwd * +#ifdef __STDC__ +getpwuid(uid_t uid) +#else +getpwuid(uid) + int uid; +#endif +{ + DBT key; + int keyuid, rval; + char bf[sizeof(keyuid) + 1]; + + if (!_pw_db && !__initdb()) + return((struct passwd *)NULL); + + bf[0] = _PW_KEYBYUID; + keyuid = uid; + bcopy(&keyuid, bf + 1, sizeof(keyuid)); + key.data = (u_char *)bf; + key.size = sizeof(keyuid) + 1; + rval = __hashpw(&key); + +#ifdef YP + if (!rval && _yp_enabled) { + char ypbuf[16]; /* big enough for 32-bit uids and then some */ + snprintf(ypbuf, sizeof ypbuf, "%u", (unsigned)uid); + rval = _getyppass(&_pw_passwd, ypbuf, "passwd.byuid"); + } +#endif + /* + * Prevent login attempts when YP is not enabled but YP entries + * are in /etc/master.passwd. + */ + if (rval && (_pw_passwd.pw_name[0] == '+'|| + _pw_passwd.pw_name[0] == '-')) rval = 0; + + endpwent(); + return(rval ? &_pw_passwd : (struct passwd *)NULL); +} + +int +setpassent(stayopen) + int stayopen; +{ + _pw_keynum = 0; +#ifdef YP + _pw_stepping_yp = _yp_done = 0; +#endif + _pw_stayopen = stayopen; + return(1); +} + +int +setpwent() +{ + _pw_keynum = 0; +#ifdef YP + _pw_stepping_yp = _yp_done = 0; +#endif + _pw_stayopen = 0; + return(1); +} + +void +endpwent() +{ + _pw_keynum = 0; +#ifdef YP + _pw_stepping_yp = _yp_done = 0; +#endif + if (_pw_db) { + (void)(_pw_db->close)(_pw_db); + _pw_db = (DB *)NULL; +#ifdef YP + _freecaches(); +#endif + } +} + +static +__initdb() +{ + static int warned; + char *p; + + p = (geteuid()) ? _PATH_MP_DB : _PATH_SMP_DB; + _pw_db = dbopen(p, O_RDONLY, 0, DB_HASH, NULL); + if (_pw_db) { +#ifdef YP + DBT key, data; + char buf[] = { _PW_KEYYPENABLED }; + key.data = buf; + key.size = 1; + if ((_pw_db->get)(_pw_db, &key, &data, 0)) { + _yp_enabled = 0; + } else { + _yp_enabled = (int)*((char *)data.data) - 2; + _createcaches(); + /* Don't even bother with this if we aren't root. */ + if (!geteuid()) { + if (!_pw_yp_domain) + if (yp_get_default_domain(&_pw_yp_domain)) + return(1); + _gotmaster = _havemaster(_pw_yp_domain); + } else _gotmaster = 0; + } +#endif + return(1); + } + if (!warned) + syslog(LOG_ERR, "%s: %m", p); + return(0); +} + +static +__hashpw(key) + DBT *key; +{ + register char *p, *t; + static u_int max; + static char *line; + DBT data; + + if ((_pw_db->get)(_pw_db, key, &data, 0)) + return(0); + p = (char *)data.data; + if (data.size > max && !(line = realloc(line, max += 1024))) + return(0); + + t = line; +#define EXPAND(e) e = t; while (*t++ = *p++); + EXPAND(_pw_passwd.pw_name); + EXPAND(_pw_passwd.pw_passwd); + bcopy(p, (char *)&_pw_passwd.pw_uid, sizeof(int)); + p += sizeof(int); + bcopy(p, (char *)&_pw_passwd.pw_gid, sizeof(int)); + p += sizeof(int); + bcopy(p, (char *)&_pw_passwd.pw_change, sizeof(time_t)); + p += sizeof(time_t); + EXPAND(_pw_passwd.pw_class); + EXPAND(_pw_passwd.pw_gecos); + EXPAND(_pw_passwd.pw_dir); + EXPAND(_pw_passwd.pw_shell); + bcopy(p, (char *)&_pw_passwd.pw_expire, sizeof(time_t)); + p += sizeof(time_t); + bcopy(p, (char *)&_pw_passwd.pw_fields, sizeof _pw_passwd.pw_fields); + p += sizeof _pw_passwd.pw_fields; + return(1); +} + +#ifdef YP +/* + * Build special +@netgroup and -@netgroup caches. We also handle ordinary + * +user/-user entries, *and* +@group/-@group entries, which are special + * cases of the +@netgroup/-@netgroup substitutions: if we can't find + * netgroup 'foo', we look for a regular user group called 'foo' and + * match against that instead. The netgroup takes precedence since the + * +group/-group support is basically just a hack to make Justin T. Gibbs + * happy. :) Sorting out all the funny business here lets us have a + * yp_enabled flag with a simple on or off value instead of the somewhat + * bogus setup we had before. + * + * We cache everything here in one shot so that we only have to scan + * each netgroup/group once. The alternative is to use innetgr() inside the + * NIS lookup functions, which would make retrieving the whole password + * database though getpwent() very slow. +user/-user entries are treated + * like @groups/@netgroups with only one member. + */ +static void +_createcaches() +{ + DBT key, data; + int i; + char bf[UT_NAMESIZE + 2]; + struct _pw_cache *p, *m; + struct _namelist *n, *namehead; + char *user, *host, *domain; + struct group *grp; + + /* + * Assume that the database has already been initialized + * but be paranoid and check that YP is in fact enabled. + */ + + if (!_yp_enabled) + return; + /* + * For the plus list, we have to store both the linked list of + * names and the +entries from the password database so we can + * do the substitution later if we find a match. + */ + bf[0] = _PW_KEYPLUSCNT; + key.data = (u_char*)bf; + key.size = 1; + if (!(_pw_db->get)(_pw_db, &key, &data, 0)) { + _pluscnt = (int)*((char *)data.data); + for (i = 0; i < _pluscnt; i++) { + bf[0] = _PW_KEYPLUSBYNUM; + bcopy(&i, bf + 1, sizeof(i) + 1); + key.size = (sizeof(i)) + 1; + if (__hashpw(&key)) { + p = (struct _pw_cache *)malloc(sizeof (struct _pw_cache)); + if (strlen(_pw_passwd.pw_name) > 2 && _pw_passwd.pw_name[1] == '@') { + setnetgrent(_pw_passwd.pw_name+2); + namehead = NULL; + while(getnetgrent(&host, &user, &domain)) { + n = (struct _namelist *)malloc(sizeof (struct _namelist)); + n->name = strdup(user); + n->next = namehead; + namehead = n; + } + /* + * If netgroup 'foo' doesn't exist, + * try group 'foo' instead. + */ + if (namehead == NULL && (grp = getgrnam(_pw_passwd.pw_name+2)) != NULL) { + while(*grp->gr_mem) { + n = (struct _namelist *)malloc(sizeof (struct _namelist)); + n->name = strdup(*grp->gr_mem); + n->next = namehead; + namehead = n; + grp->gr_mem++; + } + } + } else { + if (_pw_passwd.pw_name[1] != '@') { + namehead = (struct _namelist *)malloc(sizeof (struct _namelist)); + namehead->name = strdup(_pw_passwd.pw_name+1); + namehead->next = NULL; + } + } + p->namelist = namehead; + p->pw_entry.pw_name = strdup(_pw_passwd.pw_name); + p->pw_entry.pw_passwd = strdup(_pw_passwd.pw_passwd); + p->pw_entry.pw_uid = _pw_passwd.pw_uid; + p->pw_entry.pw_gid = _pw_passwd.pw_gid; + p->pw_entry.pw_expire = _pw_passwd.pw_expire; + p->pw_entry.pw_change = _pw_passwd.pw_change; + p->pw_entry.pw_class = strdup(_pw_passwd.pw_class); + p->pw_entry.pw_gecos = strdup(_pw_passwd.pw_gecos); + p->pw_entry.pw_dir = strdup(_pw_passwd.pw_dir); + p->pw_entry.pw_shell = strdup(_pw_passwd.pw_shell); + p->pw_entry.pw_fields = _pw_passwd.pw_fields; + p->next = _plushead; + _plushead = p; + } + } + } + + /* + * All we need for the minuslist is the usernames. + * The actual -entries data can be ignored since no substitution + * will be done: anybody on the minus list is treated like a + * non-person. + */ + bf[0] = _PW_KEYMINUSCNT; + key.data = (u_char*)bf; + key.size = 1; + if (!(_pw_db->get)(_pw_db, &key, &data, 0)) { + _minuscnt = (int)*((char *)data.data); + for (i = _minuscnt; i > -1; i--) { + bf[0] = _PW_KEYMINUSBYNUM; + bcopy(&i, bf + 1, sizeof(i) + 1); + key.size = (sizeof(i)) + 1; + if (__hashpw(&key)) { + m = (struct _pw_cache *)malloc(sizeof (struct _pw_cache)); + if (strlen (_pw_passwd.pw_name) > 2 && _pw_passwd.pw_name[1] == '@') { + namehead = NULL; + setnetgrent(_pw_passwd.pw_name+2); + while(getnetgrent(&host, &user, &domain)) { + n = (struct _namelist *)malloc(sizeof (struct _namelist)); + n->name = strdup(user); + n->next = namehead; + namehead = n; + } + /* + * If netgroup 'foo' doesn't exist, + * try group 'foo' instead. + */ + if (namehead == NULL && (grp = getgrnam(_pw_passwd.pw_name+2)) != NULL) { + while(*grp->gr_mem) { + n = (struct _namelist *)malloc(sizeof (struct _namelist)); + n->name = strdup(*grp->gr_mem); + n->next = namehead; + namehead = n; + grp->gr_mem++; + } + } + } else { + if (_pw_passwd.pw_name[1] != '@') { + namehead = (struct _namelist *)malloc(sizeof (struct _namelist)); + namehead->name = strdup(_pw_passwd.pw_name+1); + namehead->next = NULL; + } + } + /* Save just the name */ + m->pw_entry.pw_name = strdup(_pw_passwd.pw_name); + m->namelist = namehead; + m->next = _minushead; + _minushead = m; + } + } + } + endgrent(); + endnetgrent(); +} + +/* + * Free the +@netgroup/-@netgroup caches. Should be called + * from endpwent(). We have to blow away both the list of + * netgroups and the attached linked lists of usernames. + */ +static void +_freecaches() +{ +struct _pw_cache *p, *m; +struct _namelist *n; + + while (_plushead) { + while(_plushead->namelist) { + n = _plushead->namelist->next; + free(_plushead->namelist->name); + free(_plushead->namelist); + _plushead->namelist = n; + } + free(_plushead->pw_entry.pw_name); + free(_plushead->pw_entry.pw_passwd); + free(_plushead->pw_entry.pw_class); + free(_plushead->pw_entry.pw_gecos); + free(_plushead->pw_entry.pw_dir); + free(_plushead->pw_entry.pw_shell); + p = _plushead->next; + free(_plushead); + _plushead = p; + } + + while(_minushead) { + while(_minushead->namelist) { + n = _minushead->namelist->next; + free(_minushead->namelist->name); + free(_minushead->namelist); + _minushead->namelist = n; + } + m = _minushead->next; + free(_minushead); + _minushead = m; + } + _pluscnt = _minuscnt = 0; +} + +static int _scancaches(user) +char *user; +{ + register struct _pw_cache *m, *p; + register struct _namelist *n; + + if (_minuscnt && _minushead) { + m = _minushead; + while (m) { + n = m->namelist; + while (n) { + if (!strcmp(n->name,user) || *n->name == '\0') + return (1); + n = n->next; + } + m = m->next; + } + } + if (_pluscnt && _plushead) { + p = _plushead; + while (p) { + n = p->namelist; + while (n) { + if (!strcmp(n->name, user) || *n->name == '\0') + bcopy((char *)&p->pw_entry, + (char *)&_pw_passwd, sizeof(p->pw_entry)); + n = n->next; + } + p = p->next; + } + } + return(0); +} + +static int +_pw_breakout_yp(struct passwd *pw, char *res, int master) +{ + char *s, *c, *result; + static char resbuf[YPMAXRECORD+2]; + + /* + * Be triple, ultra super-duper paranoid: reject entries + * that start with a + or -. yp_mkdb and /var/yp/Makefile + * are _both_ supposed to strip these out, but you never + * know. + */ + if (*res == '+' || *res == '-') + return 0; + + /* + * The NIS protocol definition limits the size of an NIS + * record to YPMAXRECORD bytes. We need to do a copy to + * a static buffer here since the memory pointed to by + * res will be free()ed when this function returns. + */ + strncpy((char *)&resbuf, res, YPMAXRECORD); + result = (char *)&resbuf; + + /* + * XXX Sanity check: make sure all fields are valid (no NULLs). + * If we find a badly formatted entry, we punt. + */ + if ((s = strsep(&result, ":")) == NULL) return 0; /* name */ + /* + * We don't care what pw_fields says: we _always_ want the + * username returned to us by NIS. + */ + pw->pw_name = s; + pw->pw_fields |= _PWF_NAME; + + if ((s = strsep(&result, ":")) == NULL) return 0; /* password */ + if(!(pw->pw_fields & _PWF_PASSWD)) { + pw->pw_passwd = s; + pw->pw_fields |= _PWF_PASSWD; + } + + if ((s = strsep(&result, ":")) == NULL) return 0; /* uid */ + if(!(pw->pw_fields & _PWF_UID)) { + pw->pw_uid = atoi(s); + pw->pw_fields |= _PWF_UID; + } + + if ((s = strsep(&result, ":")) == NULL) return 0; /* gid */ + if(!(pw->pw_fields & _PWF_GID)) { + pw->pw_gid = atoi(s); + pw->pw_fields |= _PWF_GID; + } + + if (master) { + if ((s = strsep(&result, ":")) == NULL) return 0; /* class */ + if(!(pw->pw_fields & _PWF_CLASS)) { + pw->pw_class = s; + pw->pw_fields |= _PWF_CLASS; + } + + if ((s = strsep(&result, ":")) == NULL) return 0; /* change */ + if(!(pw->pw_fields & _PWF_CHANGE)) { + pw->pw_change = atol(s); + pw->pw_fields |= _PWF_CHANGE; + } + + if ((s = strsep(&result, ":")) == NULL) return 0; /* expire */ + if(!(pw->pw_fields & _PWF_EXPIRE)) { + pw->pw_expire = atol(s); + pw->pw_fields |= _PWF_EXPIRE; + } + } + + if ((s = strsep(&result, ":")) == NULL) return 0; /* gecos */ + if(!(pw->pw_fields & _PWF_GECOS)) { + pw->pw_gecos = s; + pw->pw_fields |= _PWF_GECOS; + } + + if ((s = strsep(&result, ":")) == NULL) return 0; /* dir */ + if(!(pw->pw_fields & _PWF_DIR)) { + pw->pw_dir = s; + pw->pw_fields |= _PWF_DIR; + } + + if ((s = strsep(&result, ":")) == NULL) return 0; /* shell */ + if(!(pw->pw_fields & _PWF_SHELL)) { + pw->pw_shell = s; + pw->pw_fields |= _PWF_SHELL; + } + + /* Be consistent. */ + if ((s = strchr(pw->pw_shell, '\n'))) *s = '\0'; + + return 1; +} + +static int +_havemaster(char *_pw_yp_domain) +{ + int keylen, resultlen; + char *key, *result; + + if (yp_first(_pw_yp_domain, "master.passwd.byname", + &key, &keylen, &result, &resultlen)) { + free(result); + return 0; + } + free(result); + return 1; +} + +static int +_getyppass(struct passwd *pw, const char *name, const char *map) +{ + char *result, *s; + int resultlen; + int rv; + char mastermap[1024]; + + if(!_pw_yp_domain) { + if(yp_get_default_domain(&_pw_yp_domain)) + return 0; + } + + sprintf(mastermap,"%s",map); + + if (_gotmaster) + sprintf(mastermap,"master.%s", map); + + if(yp_match(_pw_yp_domain, (char *)&mastermap, name, strlen(name), + &result, &resultlen)) + return 0; + + s = strchr(result, ':'); + if (s) { + *s = '\0'; + } else { + /* Must be a malformed entry if no colons. */ + free(result); + return(0); + } + _pw_passwd.pw_fields = -1; /* Impossible value */ + if (_scancaches(result)) { + free(result); + return(0); + } + /* No hits in the plus or minus lists: Bzzt! reject. */ + if (_pw_passwd.pw_fields == -1) { + free(result); + return(0); + } + *s = ':'; /* Put back the colon we previously replaced with a NUL. */ + rv = _pw_breakout_yp(pw, result, _gotmaster); + free(result); + return(rv); +} + +static int +_nextyppass(struct passwd *pw) +{ + static char *key; + static int keylen; + char *lastkey, *result, *s; + int resultlen; + int rv; + char *map = "passwd.byname"; + + if(!_pw_yp_domain) { + if(yp_get_default_domain(&_pw_yp_domain)) + return 0; + } + + if (_gotmaster) + map = "master.passwd.byname"; + + if(!_pw_stepping_yp) { + if(key) free(key); + rv = yp_first(_pw_yp_domain, map, + &key, &keylen, &result, &resultlen); + if(rv) { + return 0; + } + _pw_stepping_yp = 1; + goto unpack; + } else { +tryagain: + lastkey = key; + rv = yp_next(_pw_yp_domain, map, key, keylen, + &key, &keylen, &result, &resultlen); + free(lastkey); +unpack: + if(rv) { + _pw_stepping_yp = 0; + return 0; + } + + s = strchr(result, ':'); + if (s) { + *s = '\0'; + } else { + /* Must be a malformed entry if no colon. */ + free(result); + goto tryagain; + } + _pw_passwd.pw_fields = -1; /* Impossible value */ + if (_scancaches(result)) { + free(result); + goto tryagain; + } + /* No plus or minus hits: Bzzzt! reject. */ + if (_pw_passwd.pw_fields == -1) { + free(result); + goto tryagain; + } + *s = ':'; /* Put back colon we previously replaced with a NUL. */ + if(s = strchr(result, '\n')) *s = '\0'; + if (_pw_breakout_yp(pw, result, _gotmaster)) { + free(result); + return(1); + } else { + free(result); + goto tryagain; + } + } +} + +#endif /* YP */ |