edgroup.c revision 20747
1/*- 2 * Copyright (C) 1996 3 * David L. Nugent. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL DAVID L. NUGENT OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $Id: edgroup.c,v 1.1.1.2 1996/12/10 23:58:54 joerg Exp $ 27 */ 28 29#include <stdio.h> 30#include <stdlib.h> 31#include <string.h> 32#include <unistd.h> 33#include <stdarg.h> 34#include <errno.h> 35#include <sys/types.h> 36#include <sys/stat.h> 37#include <pwd.h> 38#include <grp.h> 39#include <fcntl.h> 40#include <sys/param.h> 41#include <ctype.h> 42 43#include "pwupd.h" 44 45static int 46isingroup(char const * name, char **mem) 47{ 48 int i; 49 50 for (i = 0; mem[i] != NULL; i++) 51 if (strcmp(name, mem[i]) == 0) 52 return i; 53 return -1; 54} 55 56static char groupfile[] = _PATH_GROUP; 57static char grouptmp[] = _PATH_GROUP ".new"; 58 59int 60editgroups(char *name, char **groups) 61{ 62 int rc = 0; 63 int infd; 64 65 if ((infd = open(groupfile, O_RDWR | O_CREAT | O_EXLOCK, 0644)) != -1) { 66 FILE *infp; 67 68 if ((infp = fdopen(infd, "r+")) == NULL) 69 close(infd); 70 else { 71 int outfd; 72 73 if ((outfd = open(grouptmp, O_RDWR | O_CREAT | O_TRUNC | O_EXLOCK, 0644)) != -1) { 74 FILE *outfp; 75 76 if ((outfp = fdopen(outfd, "w+")) == NULL) 77 close(outfd); 78 else { 79 int linelen = PWBUFSZ; 80 int outlen = PWBUFSZ; 81 int memlen = 200; /* Arbitrary */ 82 char *line = malloc(linelen); 83 char *outl = malloc(outlen); 84 char **mems = malloc(memlen * sizeof(char *)); 85 int namlen = strlen(name); 86 87 if (line == NULL || outl == NULL || mems == NULL) { 88 mem_abort: 89 rc = 0; 90 } else { 91 while (fgets(line, linelen, infp) != NULL) { 92 char *p; 93 int l; 94 95 while ((p = strchr(line, '\n')) == NULL) 96 { 97 if (extendline(&line, &linelen, linelen + PWBUFSZ) == -1) { 98 goto mem_abort; 99 } 100 l = strlen(line); 101 if (fgets(line + l, linelen - l, infp) == NULL) 102 break; /* No newline terminator on last line */ 103 } 104 l = strlen(line) + namlen + 1; 105 if (extendline(&outl, &outlen, l) == -1) { 106 goto mem_abort; 107 } 108 if (*line == '#') 109 strcpy(outl, line); 110 else if (*line == '\n') 111 *outl = '\0'; 112 else { 113 int i, 114 mno = 0; 115 char *cp = line; 116 char const *sep = ":\n"; 117 struct group grp; 118 119 memset(&grp, 0, sizeof grp); 120 for (i = 0; (p = strsep(&cp, sep)) != NULL; i++) { 121 switch (i) { 122 case 0: /* Group name */ 123 grp.gr_name = p; 124 break; 125 case 1: /* Group password */ 126 grp.gr_passwd = p; 127 break; 128 case 2: /* Group id */ 129 grp.gr_gid = atoi(p); 130 break; 131 case 3: /* Member list */ 132 cp = p; 133 sep = ",\n"; 134 break; 135 default: /* Individual members */ 136 if (*p) { 137 if (extendarray(&mems, &memlen, mno + 2) == -1) { 138 goto mem_abort; 139 } 140 mems[mno++] = p; 141 } 142 break; 143 } 144 } 145 if (i < 2) /* Bail out - insufficient fields */ 146 continue; 147 148 grp.gr_mem = mems; 149 for (i = mno; i < memlen; i++) 150 mems[i] = NULL; 151 152 /* 153 * Delete from group, or add to group? 154 */ 155 if (groups == NULL || isingroup(grp.gr_name, groups) == -1) { /* Delete */ 156 int idx; 157 158 while ((idx = isingroup(name, mems)) != -1) { 159 for (i = idx; i < (memlen - 1); i++) 160 mems[i] = mems[i + 1]; 161 mems[i] = NULL; 162 --mno; 163 } 164 /* 165 * Special case - deleting user and group may be user's own 166 */ 167 if (groups == NULL && mems[0] == NULL && strcmp(name, grp.gr_name) == 0) { 168 /* 169 * First, make _sure_ we don't have other members 170 */ 171 struct passwd *pwd; 172 173 setpwent(); 174 while ((pwd = getpwent()) != NULL && pwd->pw_gid != grp.gr_gid); 175 endpwent(); 176 if (pwd == NULL) /* No members at all */ 177 continue; /* Drop the group */ 178 } 179 } else if (isingroup(name, mems) == -1) { 180 if (extendarray(&mems, &memlen, mno + 2) == -1) { 181 goto mem_abort; 182 } 183 grp.gr_mem = mems; /* May have realloced() */ 184 mems[mno++] = name; 185 mems[mno ] = NULL; 186 } 187 fmtgrentry(&outl, &outlen, &grp, PWF_GROUP); 188 } 189 fputs(outl, outfp); 190 } 191 if (fflush(outfp) != EOF) { 192 rc = 1; 193 194 /* 195 * Copy data back into the original file and truncate 196 */ 197 rewind(infp); 198 rewind(outfp); 199 while (fgets(outl, outlen, outfp) != NULL) 200 fputs(outl, infp); 201 202 /* 203 * This is a gross hack, but we may have corrupted the 204 * original file. Unfortunately, it will lose preservation 205 * of the inode. 206 */ 207 if (fflush(infp) == EOF || ferror(infp)) 208 rc = rename(grouptmp, groupfile) == 0; 209 else 210 ftruncate(infd, ftell(infp)); 211 } 212 } 213 free(mems); 214 free(outl); 215 free(line); 216 fclose(outfp); 217 } 218 remove(grouptmp); 219 } 220 fclose(infp); 221 } 222 } 223 return rc; 224} 225