Return to getgrent.c CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / sudo / plugins / sample_group

Annotation of embedaddon/sudo/plugins/sample_group/getgrent.c, revision 1.1.1.1

1.1       misho       1: /*
                      2:  * Copyright (c) 2005,2008,2010-2011 Todd C. Miller <Todd.Miller@courtesan.com>
                      3:  *
                      4:  * Permission to use, copy, modify, and distribute this software for any
                      5:  * purpose with or without fee is hereby granted, provided that the above
                      6:  * copyright notice and this permission notice appear in all copies.
                      7:  *
                      8:  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
                      9:  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
                     10:  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
                     11:  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
                     12:  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
                     13:  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
                     14:  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
                     15:  */
                     16: 
                     17: /*
                     18:  * Trivial replacements for the libc getgr{uid,nam}() routines.
                     19:  */
                     20: 
                     21: #include <config.h>
                     22: 
                     23: #include <sys/types.h>
                     24: #include <sys/param.h>
                     25: #include <stdio.h>
                     26: #ifdef STDC_HEADERS
                     27: # include <stdlib.h>
                     28: # include <stddef.h>
                     29: #else
                     30: # ifdef HAVE_STDLIB_H
                     31: #  include <stdlib.h>
                     32: # endif
                     33: #endif /* STDC_HEADERS */
                     34: #ifdef HAVE_STRING_H
                     35: # if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS)
                     36: #  include <memory.h>
                     37: # endif
                     38: # include <string.h>
                     39: #endif /* HAVE_STRING_H */
                     40: #ifdef HAVE_STRINGS_H
                     41: # include <strings.h>
                     42: #endif /* HAVE_STRINGS_H */
                     43: #include <fcntl.h>
                     44: #include <limits.h>
                     45: #include <pwd.h>
                     46: #include <grp.h>
                     47: 
                     48: #include "missing.h"
                     49: 
                     50: #ifndef LINE_MAX
                     51: # define LINE_MAX 2048
                     52: #endif
                     53: 
                     54: #undef GRMEM_MAX
                     55: #define GRMEM_MAX 200
                     56: 
                     57: static FILE *grf;
                     58: static const char *grfile = "/etc/group";
                     59: static int gr_stayopen;
                     60: 
                     61: void mysetgrfile(const char *);
                     62: void mysetgrent(void);
                     63: void myendgrent(void);
                     64: struct group *mygetgrent(void);
                     65: struct group *mygetgrnam(const char *);
                     66: struct group *mygetgrgid(gid_t);
                     67: 
                     68: void
                     69: mysetgrfile(const char *file)
                     70: {
                     71:     grfile = file;
                     72:     if (grf != NULL)
                     73:        myendgrent();
                     74: }
                     75: 
                     76: void
                     77: mysetgrent(void)
                     78: {
                     79:     if (grf == NULL) {
                     80:        grf = fopen(grfile, "r");
                     81:        if (grf != NULL)
                     82:            fcntl(fileno(grf), F_SETFD, FD_CLOEXEC);
                     83:     } else {
                     84:        rewind(grf);
                     85:     }
                     86:     gr_stayopen = 1;
                     87: }
                     88: 
                     89: void
                     90: myendgrent(void)
                     91: {
                     92:     if (grf != NULL) {
                     93:        fclose(grf);
                     94:        grf = NULL;
                     95:     }
                     96:     gr_stayopen = 0;
                     97: }
                     98: 
                     99: struct group *
                    100: mygetgrent(void)
                    101: {
                    102:     static struct group gr;
                    103:     static char grbuf[LINE_MAX], *gr_mem[GRMEM_MAX+1];
                    104:     size_t len;
                    105:     char *cp, *colon;
                    106:     int n;
                    107: 
                    108:     if ((colon = fgets(grbuf, sizeof(grbuf), grf)) == NULL)
                    109:        return NULL;
                    110: 
                    111:     memset(&gr, 0, sizeof(gr));
                    112:     if ((colon = strchr(cp = colon, ':')) == NULL)
                    113:        return NULL;
                    114:     *colon++ = '\0';
                    115:     gr.gr_name = cp;
                    116:     if ((colon = strchr(cp = colon, ':')) == NULL)
                    117:        return NULL;
                    118:     *colon++ = '\0';
                    119:     gr.gr_passwd = cp;
                    120:     if ((colon = strchr(cp = colon, ':')) == NULL)
                    121:        return NULL;
                    122:     *colon++ = '\0';
                    123:     gr.gr_gid = atoi(cp);
                    124:     len = strlen(colon);
                    125:     if (len > 0 && colon[len - 1] == '\n')
                    126:        colon[len - 1] = '\0';
                    127:     if (*colon != '\0') {
                    128:        gr.gr_mem = gr_mem;
                    129:        cp = strtok(colon, ",");
                    130:        for (n = 0; cp != NULL && n < GRMEM_MAX; n++) {
                    131:            gr.gr_mem[n] = cp;
                    132:            cp = strtok(NULL, ",");
                    133:        }
                    134:        gr.gr_mem[n++] = NULL;
                    135:     } else
                    136:        gr.gr_mem = NULL;
                    137:     return &gr;
                    138: }
                    139: 
                    140: struct group *
                    141: mygetgrnam(const char *name)
                    142: {
                    143:     struct group *gr;
                    144: 
                    145:     if (grf == NULL) {
                    146:        if ((grf = fopen(grfile, "r")) == NULL)
                    147:            return NULL;
                    148:        fcntl(fileno(grf), F_SETFD, FD_CLOEXEC);
                    149:     } else {
                    150:        rewind(grf);
                    151:     }
                    152:     while ((gr = mygetgrent()) != NULL) {
                    153:        if (strcmp(gr->gr_name, name) == 0)
                    154:            break;
                    155:     }
                    156:     if (!gr_stayopen) {
                    157:        fclose(grf);
                    158:        grf = NULL;
                    159:     }
                    160:     return gr;
                    161: }
                    162: 
                    163: struct group *
                    164: mygetgrgid(gid_t gid)
                    165: {
                    166:     struct group *gr;
                    167: 
                    168:     if (grf == NULL) {
                    169:        if ((grf = fopen(grfile, "r")) == NULL)
                    170:            return NULL;
                    171:        fcntl(fileno(grf), F_SETFD, FD_CLOEXEC);
                    172:     } else {
                    173:        rewind(grf);
                    174:     }
                    175:     while ((gr = mygetgrent()) != NULL) {
                    176:        if (gr->gr_gid == gid)
                    177:            break;
                    178:     }
                    179:     if (!gr_stayopen) {
                    180:        fclose(grf);
                    181:        grf = NULL;
                    182:     }
                    183:     return gr;
                    184: }