edgroup.c revision 126753 
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  "$FreeBSD: head/usr.sbin/pw/edgroup.c 126753 2004-03-08 20:31:37Z kensmith $";
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 | O_EXLOCK, 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, 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.
211							 */
212							if (fflush(infp) == EOF || ferror(infp))
213								rc = rename(grouptmp, groupfile) == 0;
214							else
215								ftruncate(infd, ftell(infp));
216						}
217					}
218					free(mems);
219					free(outl);
220			    		free(line);
221					fclose(outfp);
222				}
223				remove(grouptmp);
224			}
225			fclose(infp);
226		}
227	}
228	return rc;
229}
230