edgroup.c revision 44229
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 27#ifndef lint 28static const char rcsid[] = 29 "$Id: edgroup.c,v 1.6 1998/07/16 17:18:22 nate Exp $"; 30#endif /* not lint */ 31 32#include <stdio.h> 33#include <stdlib.h> 34#include <string.h> 35#include <unistd.h> 36#include <stdarg.h> 37#include <sys/types.h> 38#include <sys/stat.h> 39#include <pwd.h> 40#include <grp.h> 41#include <fcntl.h> 42#include <sys/param.h> 43#include <ctype.h> 44 45#include "pwupd.h" 46 47static int 48isingroup(char const * name, char **mem) 49{ 50 int i; 51 52 for (i = 0; mem[i] != NULL; i++) 53 if (strcmp(name, mem[i]) == 0) 54 return i; 55 return -1; 56} 57 58int 59editgroups(char *name, char **groups) 60{ 61 int rc = 0; 62 int infd; 63 char groupfile[MAXPATHLEN]; 64 char grouptmp[MAXPATHLEN]; 65 66 strncpy(groupfile, getgrpath(_GROUP), MAXPATHLEN - 5); 67 groupfile[MAXPATHLEN - 5] = '\0'; 68 strcpy(grouptmp, groupfile); 69 strcat(grouptmp, ".new"); 70 71 if ((infd = open(groupfile, O_RDWR | O_CREAT, 0644)) != -1) { 72 FILE *infp; 73 74 if ((infp = fdopen(infd, "r+")) == NULL) 75 close(infd); 76 else { 77 int outfd; 78 79 if ((outfd = open(grouptmp, O_RDWR | O_CREAT | O_TRUNC | O_EXLOCK, 0644)) != -1) { 80 FILE *outfp; 81 82 if ((outfp = fdopen(outfd, "w+")) == NULL) 83 close(outfd); 84 else { 85 int linelen = PWBUFSZ; 86 int outlen = PWBUFSZ; 87 int memlen = 200; /* Arbitrary */ 88 char *line = malloc(linelen); 89 char *outl = malloc(outlen); 90 char **mems = malloc(memlen * sizeof(char *)); 91 int namlen = strlen(name); 92 93 if (line == NULL || outl == NULL || mems == NULL) { 94 mem_abort: 95 rc = 0; 96 } else { 97 while (fgets(line, linelen, infp) != NULL) { 98 char *p; 99 int l; 100 101 while ((p = strchr(line, '\n')) == NULL) 102 { 103 if (extendline(&line, &linelen, linelen + PWBUFSZ) == -1) { 104 goto mem_abort; 105 } 106 l = strlen(line); 107 if (fgets(line + l, linelen - l, infp) == NULL) 108 break; /* No newline terminator on last line */ 109 } 110 l = strlen(line) + namlen + 1; 111 if (extendline(&outl, &outlen, l) == -1) { 112 goto mem_abort; 113 } 114 if (*line == '#') 115 strcpy(outl, line); 116 else if (*line == '\n') 117 *outl = '\0'; 118 else { 119 int i, 120 mno = 0; 121 char *cp = line; 122 char const *sep = ":\n"; 123 struct group grp; 124 125 memset(&grp, 0, sizeof grp); 126 for (i = 0; (p = strsep(&cp, sep)) != NULL; i++) { 127 switch (i) { 128 case 0: /* Group name */ 129 grp.gr_name = p; 130 break; 131 case 1: /* Group password */ 132 grp.gr_passwd = p; 133 break; 134 case 2: /* Group id */ 135 grp.gr_gid = atoi(p); 136 break; 137 case 3: /* Member list */ 138 cp = p; 139 sep = ",\n"; 140 break; 141 default: /* Individual members */ 142 if (*p) { 143 if (extendarray(&mems, &memlen, mno + 2) == -1) { 144 goto mem_abort; 145 } 146 mems[mno++] = p; 147 } 148 break; 149 } 150 } 151 if (i < 2) /* Bail out - insufficient fields */ 152 continue; 153 154 grp.gr_mem = mems; 155 for (i = mno; i < memlen; i++) 156 mems[i] = NULL; 157 158 /* 159 * Delete from group, or add to group? 160 */ 161 if (groups == NULL || isingroup(grp.gr_name, groups) == -1) { /* Delete */ 162 int idx; 163 164 while ((idx = isingroup(name, mems)) != -1) { 165 for (i = idx; i < (memlen - 1); i++) 166 mems[i] = mems[i + 1]; 167 mems[i] = NULL; 168 --mno; 169 } 170 /* 171 * Special case - deleting user and group may be user's own 172 */ 173 if (groups == NULL && mems[0] == NULL && strcmp(name, grp.gr_name) == 0) { 174 /* 175 * First, make _sure_ we don't have other members 176 */ 177 struct passwd *pwd; 178 179 SETPWENT(); 180 while ((pwd = GETPWENT()) != NULL && (gid_t)pwd->pw_gid != (gid_t)grp.gr_gid); 181 ENDPWENT(); 182 if (pwd == NULL) /* No members at all */ 183 continue; /* Drop the group */ 184 } 185 } else if (isingroup(name, mems) == -1) { 186 if (extendarray(&mems, &memlen, mno + 2) == -1) { 187 goto mem_abort; 188 } 189 grp.gr_mem = mems; /* May have realloced() */ 190 mems[mno++] = name; 191 mems[mno ] = NULL; 192 } 193 fmtgrentry(&outl, &outlen, &grp, PWF_GROUP); 194 } 195 fputs(outl, outfp); 196 } 197 if (fflush(outfp) != EOF) { 198 rc = 1; 199 200 /* 201 * Copy data back into the original file and truncate 202 */ 203 rewind(infp); 204 rewind(outfp); 205 while (fgets(outl, outlen, outfp) != NULL) 206 fputs(outl, infp); 207 208 /* 209 * This is a gross hack, but we may have corrupted the 210 * original file. Unfortunately, it will lose preservation 211 * of the inode. 212 */ 213 if (fflush(infp) == EOF || ferror(infp)) 214 rc = rename(grouptmp, groupfile) == 0; 215 else 216 ftruncate(infd, ftell(infp)); 217 } 218 } 219 free(mems); 220 free(outl); 221 free(line); 222 fclose(outfp); 223 } 224 remove(grouptmp); 225 } 226 fclose(infp); 227 } 228 } 229 return rc; 230} 231