1 /* $OpenBSD: pw_dup.c,v 1.9 2019/01/25 00:19:25 millert Exp $ */
2
3 /*
4 * Copyright (c) 2000, 2002 Todd C. Miller <millert@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 *
18 * Sponsored in part by the Defense Advanced Research Projects
19 * Agency (DARPA) and Air Force Research Laboratory, Air Force
20 * Materiel Command, USAF, under agreement number F39502-99-1-0512.
21 */
22
23 #include <sys/types.h>
24
25 #include <pwd.h>
26 #include <stdlib.h>
27 #include <stdio.h>
28 #include <string.h>
29
30 #define PW_SIZE(name, size) \
31 do { \
32 if (pw->name) { \
33 size = strlen(pw->name) + 1; \
34 total += size; \
35 } \
36 } while (0)
37
38 #define PW_COPY(name, size) \
39 do { \
40 if (pw->name) { \
41 (void)memcpy(cp, pw->name, size); \
42 newpw->name = cp; \
43 cp += size; \
44 } \
45 } while (0)
46
47 struct passwd *
pw_dup(const struct passwd * pw)48 pw_dup(const struct passwd *pw)
49 {
50 char *cp;
51 size_t nsize, psize, csize, gsize, dsize, ssize, total;
52 struct passwd *newpw;
53
54 /* Allocate in one big chunk for easy freeing */
55 total = sizeof(struct passwd);
56 PW_SIZE(pw_name, nsize);
57 PW_SIZE(pw_passwd, psize);
58 PW_SIZE(pw_class, csize);
59 PW_SIZE(pw_gecos, gsize);
60 PW_SIZE(pw_dir, dsize);
61 PW_SIZE(pw_shell, ssize);
62
63 if ((cp = malloc(total)) == NULL)
64 return (NULL);
65 newpw = (struct passwd *)cp;
66
67 /*
68 * Copy in passwd contents and make strings relative to space
69 * at the end of the buffer.
70 */
71 (void)memcpy(newpw, pw, sizeof(struct passwd));
72 cp += sizeof(struct passwd);
73
74 PW_COPY(pw_name, nsize);
75 PW_COPY(pw_passwd, psize);
76 PW_COPY(pw_class, csize);
77 PW_COPY(pw_gecos, gsize);
78 PW_COPY(pw_dir, dsize);
79 PW_COPY(pw_shell, ssize);
80
81 return (newpw);
82 }
83 DEF_WEAK(pw_dup);
84