1/*
2   Unix SMB/CIFS implementation.
3
4   Safe versions of getpw* calls
5
6   Copyright (C) Andrew Bartlett 2002
7
8   This program is free software; you can redistribute it and/or modify
9   it under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 2 of the License, or
11   (at your option) any later version.
12
13   This program is distributed in the hope that it will be useful,
14   but WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16   GNU General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with this program; if not, write to the Free Software
20   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21*/
22
23#include "includes.h"
24
25struct passwd *tcopy_passwd(TALLOC_CTX *mem_ctx, const struct passwd *from)
26{
27	struct passwd *ret = TALLOC_P(mem_ctx, struct passwd);
28	if (!ret) {
29		return NULL;
30	}
31	ret->pw_name = talloc_strdup(ret, from->pw_name);
32	ret->pw_passwd = talloc_strdup(ret, from->pw_passwd);
33	ret->pw_uid = from->pw_uid;
34	ret->pw_gid = from->pw_gid;
35	ret->pw_gecos = talloc_strdup(ret, from->pw_gecos);
36	ret->pw_dir = talloc_strdup(ret, from->pw_dir);
37	ret->pw_shell = talloc_strdup(ret, from->pw_shell);
38	return ret;
39}
40
41#define PWNAMCACHE_SIZE 4
42static struct passwd **pwnam_cache = NULL;
43
44static void init_pwnam_cache(void)
45{
46	if (pwnam_cache != NULL)
47		return;
48
49	pwnam_cache = TALLOC_ZERO_ARRAY(NULL, struct passwd *,
50					PWNAMCACHE_SIZE);
51	if (pwnam_cache == NULL) {
52		smb_panic("Could not init pwnam_cache\n");
53	}
54
55	return;
56}
57
58void flush_pwnam_cache(void)
59{
60	TALLOC_FREE(pwnam_cache);
61	pwnam_cache = NULL;
62	init_pwnam_cache();
63}
64
65struct passwd *getpwnam_alloc(TALLOC_CTX *mem_ctx, const char *name)
66{
67	int i;
68
69	struct passwd *temp;
70
71	init_pwnam_cache();
72
73	for (i=0; i<PWNAMCACHE_SIZE; i++) {
74		if ((pwnam_cache[i] != NULL) &&
75		    (strcmp(name, pwnam_cache[i]->pw_name) == 0)) {
76			DEBUG(10, ("Got %s from pwnam_cache\n", name));
77			return (struct passwd *)talloc_reference(mem_ctx, pwnam_cache[i]);
78		}
79	}
80
81	temp = sys_getpwnam(name);
82
83	if (!temp) {
84#if 0
85		if (errno == ENOMEM) {
86			/* what now? */
87		}
88#endif
89		return NULL;
90	}
91
92	for (i=0; i<PWNAMCACHE_SIZE; i++) {
93		if (pwnam_cache[i] == NULL)
94			break;
95	}
96
97	if (i == PWNAMCACHE_SIZE)
98		i = rand() % PWNAMCACHE_SIZE;
99
100	if (pwnam_cache[i] != NULL) {
101		TALLOC_FREE(pwnam_cache[i]);
102	}
103
104	pwnam_cache[i] = tcopy_passwd(pwnam_cache, temp);
105	if (pwnam_cache[i]!= NULL && mem_ctx != NULL) {
106		return (struct passwd *)talloc_reference(mem_ctx, pwnam_cache[i]);
107	}
108
109	return tcopy_passwd(NULL, pwnam_cache[i]);
110}
111
112struct passwd *getpwuid_alloc(TALLOC_CTX *mem_ctx, uid_t uid)
113{
114	struct passwd *temp;
115
116	temp = sys_getpwuid(uid);
117
118	if (!temp) {
119#if 0
120		if (errno == ENOMEM) {
121			/* what now? */
122		}
123#endif
124		return NULL;
125	}
126
127	return tcopy_passwd(mem_ctx, temp);
128}
129