diff options
Diffstat (limited to 'lib/libc/gen/getgrent.c')
-rw-r--r-- | lib/libc/gen/getgrent.c | 553 |
1 files changed, 553 insertions, 0 deletions
diff --git a/lib/libc/gen/getgrent.c b/lib/libc/gen/getgrent.c new file mode 100644 index 0000000..5b5c9da --- /dev/null +++ b/lib/libc/gen/getgrent.c @@ -0,0 +1,553 @@ +/* + * Copyright (c) 1989, 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[] = "@(#)getgrent.c 8.2 (Berkeley) 3/21/94"; +#endif /* LIBC_SCCS and not lint */ + +#include <sys/types.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <grp.h> + +static FILE *_gr_fp; +static struct group _gr_group; +static int _gr_stayopen; +static int grscan(), start_gr(); +#ifdef YP +#include <rpc/rpc.h> +#include <rpcsvc/yp_prot.h> +#include <rpcsvc/ypclnt.h> +static int _gr_stepping_yp; +static int _gr_yp_enabled; +static int _getypgroup(struct group *, const char *, char *); +static int _nextypgroup(struct group *); +#endif + +/* initial size for malloc and increase steps for realloc */ +#define MAXGRP 64 +#define MAXLINELENGTH 256 + +static char **members; /* list of group members */ +static int maxgrp; /* current length of **mebers */ +static char *line; /* temp buffer for group line */ +static int maxlinelength; /* current length of *line */ + +/* + * Lines longer than MAXLINELENGTHLIMIT will be count as an error. + * <= 0 disable check for maximum line length + * 256K is enough for 64,000 uids + */ +#define MAXLINELENGTHLIMIT (256 * 1024) +#define GROUP_IGNORE_COMMENTS 1 /* allow comments in /etc/group */ + +struct group * +getgrent() +{ + if (!_gr_fp && !start_gr()) { + return NULL; + } + +#ifdef YP + if (_gr_stepping_yp) { + if (_nextypgroup(&_gr_group)) + return(&_gr_group); + } +tryagain: +#endif + + if (!grscan(0, 0, NULL)) + return(NULL); +#ifdef YP + if(_gr_group.gr_name[0] == '+' && _gr_group.gr_name[1]) { + _getypgroup(&_gr_group, &_gr_group.gr_name[1], + "group.byname"); + } else if(_gr_group.gr_name[0] == '+') { + if (!_nextypgroup(&_gr_group)) + goto tryagain; + else + return(&_gr_group); + } +#endif + return(&_gr_group); +} + +struct group * +getgrnam(name) + const char *name; +{ + int rval; + + if (!start_gr()) + return(NULL); +#ifdef YP + tryagain: +#endif + rval = grscan(1, 0, name); +#ifdef YP + if(rval == -1 && (_gr_yp_enabled < 0 || (_gr_yp_enabled && + _gr_group.gr_name[0] == '+'))) { + if (!(rval = _getypgroup(&_gr_group, name, "group.byname"))) + goto tryagain; + } +#endif + if (!_gr_stayopen) + endgrent(); + return(rval ? &_gr_group : NULL); +} + +struct group * +#ifdef __STDC__ +getgrgid(gid_t gid) +#else +getgrgid(gid) + gid_t gid; +#endif +{ + int rval; + + if (!start_gr()) + return(NULL); +#ifdef YP + tryagain: +#endif + rval = grscan(1, gid, NULL); +#ifdef YP + if(rval == -1 && _gr_yp_enabled) { + char buf[16]; + snprintf(buf, sizeof buf, "%d", (unsigned)gid); + if (!(rval = _getypgroup(&_gr_group, buf, "group.bygid"))) + goto tryagain; + } +#endif + if (!_gr_stayopen) + endgrent(); + return(rval ? &_gr_group : NULL); +} + +static int +start_gr() +{ + if (_gr_fp) { + rewind(_gr_fp); + return(1); + } + _gr_fp = fopen(_PATH_GROUP, "r"); + if(!_gr_fp) return 0; +#ifdef YP + /* + * This is a disgusting hack, used to determine when YP is enabled. + * This would be easier if we had a group database to go along with + * the password database. + */ + { + char *line; + size_t linelen; + _gr_yp_enabled = 0; + while((line = fgetln(_gr_fp, &linelen)) != NULL) { + if(line[0] == '+') { + if(line[1] && line[1] != ':' && !_gr_yp_enabled) { + _gr_yp_enabled = 1; + } else { + _gr_yp_enabled = -1; + break; + } + } + } + rewind(_gr_fp); + } +#endif + + if (maxlinelength == 0) { + if ((line = (char *)malloc(sizeof(char) * + MAXLINELENGTH)) == NULL) + return(0); + maxlinelength += MAXLINELENGTH; + } + + if (maxgrp == 0) { + if ((members = (char **)malloc(sizeof(char **) * + MAXGRP)) == NULL) + return(0); + maxgrp += MAXGRP; + } + + return 1; +} + +int +setgrent() +{ + return(setgroupent(0)); +} + +int +setgroupent(stayopen) + int stayopen; +{ + if (!start_gr()) + return(0); + _gr_stayopen = stayopen; +#ifdef YP + _gr_stepping_yp = 0; +#endif + return(1); +} + +void +endgrent() +{ +#ifdef YP + _gr_stepping_yp = 0; +#endif + if (_gr_fp) { + (void)fclose(_gr_fp); + _gr_fp = NULL; + } +} + +static int +grscan(search, gid, name) + register int search, gid; + register char *name; +{ + register char *cp, **m; + char *bp; + + +#ifdef YP + int _ypfound; +#endif + for (;;) { +#ifdef YP + _ypfound = 0; +#endif + if (fgets(line, maxlinelength, _gr_fp) == NULL) + return(0); + + if (!index(line, '\n')) { + do { + if (feof(_gr_fp)) + return(0); + + /* don't allocate infinite memory */ + if (MAXLINELENGTHLIMIT > 0 && + maxlinelength >= MAXLINELENGTHLIMIT) + return(0); + + if ((line = (char *)reallocf(line, + sizeof(char) * + (maxlinelength + MAXLINELENGTH))) == NULL) + return(0); + + if (fgets(line + maxlinelength - 1, + MAXLINELENGTH + 1, _gr_fp) == NULL) + return(0); + + maxlinelength += MAXLINELENGTH; + } while (!index(line + maxlinelength - + MAXLINELENGTH - 1, '\n')); + } + +#ifdef GROUP_IGNORE_COMMENTS + /* + * Ignore comments: ^[ \t]*# + */ + for (cp = line; *cp != '\0'; cp++) + if (*cp != ' ' && *cp != '\t') + break; + if (*cp == '#' || *cp == '\0') + continue; +#endif + + bp = line; + + if ((_gr_group.gr_name = strsep(&bp, ":\n")) == NULL) + break; +#ifdef YP + /* + * XXX We need to be careful to avoid proceeding + * past this point under certain circumstances or + * we risk dereferencing null pointers down below. + */ + if (_gr_group.gr_name[0] == '+') { + if (strlen(_gr_group.gr_name) == 1) { + switch(search) { + case 0: + return(1); + case 1: + return(-1); + default: + return(0); + } + } else { + cp = &_gr_group.gr_name[1]; + if (search && name != NULL) + if (strcmp(cp, name)) + continue; + if (!_getypgroup(&_gr_group, cp, + "group.byname")) + continue; + if (search && name == NULL) + if (gid != _gr_group.gr_gid) + continue; + /* We're going to override -- tell the world. */ + _ypfound++; + } + } +#else + if (_gr_group.gr_name[0] == '+') + continue; +#endif /* YP */ + if (search && name) { + if(strcmp(_gr_group.gr_name, name)) { + continue; + } + } +#ifdef YP + if ((cp = strsep(&bp, ":\n")) == NULL) + if (_ypfound) + return(1); + else + break; + if (strlen(cp) || !_ypfound) + _gr_group.gr_passwd = cp; +#else + if ((_gr_group.gr_passwd = strsep(&bp, ":\n")) == NULL) + break; +#endif + if (!(cp = strsep(&bp, ":\n"))) +#ifdef YP + if (_ypfound) + return(1); + else +#endif + continue; +#ifdef YP + /* + * Hurm. Should we be doing this? We allow UIDs to + * be overridden -- what about GIDs? + */ + if (!_ypfound) +#endif + _gr_group.gr_gid = atoi(cp); + if (search && name == NULL && _gr_group.gr_gid != gid) + continue; + cp = NULL; + if (bp == NULL) /* !!! Must check for this! */ + break; +#ifdef YP + if ((cp = strsep(&bp, ":\n")) == NULL) + break; + + if (!strlen(cp) && _ypfound) + return(1); + else + members[0] = NULL; + bp = cp; + cp = NULL; +#endif + for (m = members; ; bp++) { + if (m == (members + maxgrp - 1)) { + if ((members = (char **) + reallocf(members, + sizeof(char **) * + (maxgrp + MAXGRP))) == NULL) + return(0); + m = members + maxgrp - 1; + maxgrp += MAXGRP; + } + if (*bp == ',') { + if (cp) { + *bp = '\0'; + *m++ = cp; + cp = NULL; + } + } else if (*bp == '\0' || *bp == '\n' || *bp == ' ') { + if (cp) { + *bp = '\0'; + *m++ = cp; + } + break; + } else if (cp == NULL) + cp = bp; + + } + _gr_group.gr_mem = members; + *m = NULL; + return(1); + } + /* NOTREACHED */ + return (0); +} + +#ifdef YP + +static int +_gr_breakout_yp(struct group *gr, char *result) +{ + char *s, *cp; + char **m; + + /* + * XXX If 's' ends up being a NULL pointer, punt on this group. + * It means the NIS group entry is badly formatted and should + * be skipped. + */ + if ((s = strsep(&result, ":")) == NULL) return 0; /* name */ + gr->gr_name = s; + + if ((s = strsep(&result, ":")) == NULL) return 0; /* password */ + gr->gr_passwd = s; + + if ((s = strsep(&result, ":")) == NULL) return 0; /* gid */ + gr->gr_gid = atoi(s); + + if ((s = result) == NULL) return 0; + cp = 0; + + for (m = members; ; s++) { + if (m == members + maxgrp - 1) { + if ((members = (char **)reallocf(members, + sizeof(char **) * (maxgrp + MAXGRP))) == NULL) + return(0); + m = members + maxgrp - 1; + maxgrp += MAXGRP; + } + if (*s == ',') { + if (cp) { + *s = '\0'; + *m++ = cp; + cp = NULL; + } + } else if (*s == '\0' || *s == '\n' || *s == ' ') { + if (cp) { + *s = '\0'; + *m++ = cp; + } + break; + } else if (cp == NULL) { + cp = s; + } + } + _gr_group.gr_mem = members; + *m = NULL; + + return 1; +} + +static char *_gr_yp_domain; + +static int +_getypgroup(struct group *gr, const char *name, char *map) +{ + char *result, *s; + static char resultbuf[YPMAXRECORD + 2]; + int resultlen; + + if(!_gr_yp_domain) { + if(yp_get_default_domain(&_gr_yp_domain)) + return 0; + } + + if(yp_match(_gr_yp_domain, map, name, strlen(name), + &result, &resultlen)) + return 0; + + s = strchr(result, '\n'); + if(s) *s = '\0'; + + if(resultlen >= sizeof resultbuf) return 0; + strncpy(resultbuf, result, resultlen); + resultbuf[resultlen] = '\0'; + free(result); + return(_gr_breakout_yp(gr, resultbuf)); + +} + + +static int +_nextypgroup(struct group *gr) +{ + static char *key; + static int keylen; + char *lastkey, *result; + static char resultbuf[YPMAXRECORD + 2]; + int resultlen; + int rv; + + if(!_gr_yp_domain) { + if(yp_get_default_domain(&_gr_yp_domain)) + return 0; + } + + if(!_gr_stepping_yp) { + if(key) free(key); + rv = yp_first(_gr_yp_domain, "group.byname", + &key, &keylen, &result, &resultlen); + if(rv) { + return 0; + } + _gr_stepping_yp = 1; + goto unpack; + } else { +tryagain: + lastkey = key; + rv = yp_next(_gr_yp_domain, "group.byname", key, keylen, + &key, &keylen, &result, &resultlen); + free(lastkey); +unpack: + if(rv) { + _gr_stepping_yp = 0; + return 0; + } + + if(resultlen > sizeof(resultbuf)) { + free(result); + goto tryagain; + } + + strncpy(resultbuf, result, resultlen); + resultbuf[resultlen] = '\0'; + free(result); + if((result = strchr(resultbuf, '\n')) != NULL) + *result = '\0'; + if (_gr_breakout_yp(gr, resultbuf)) + return(1); + else + goto tryagain; + } +} + +#endif /* YP */ |