1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
/*
** Copyright 1998 - 2002 Double Precision, Inc. See COPYING for
** distribution information.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <grp.h>
#include <pwd.h>
#include <errno.h>
#include "numlib.h"
void libmail_changegroup(gid_t gid)
{
if ( setgid(gid))
{
perror("setgid");
exit(1);
}
#if HAVE_SETGROUPS
if ( getuid() == 0 && setgroups(1, &gid) )
{
perror("setgroups");
exit(1);
}
#endif
}
void libmail_changeuidgid(uid_t uid, gid_t gid)
{
libmail_changegroup(gid);
if ( setuid(uid))
{
perror("setuid");
exit(1);
}
}
void libmail_changeusername(const char *uname, const gid_t *forcegrp)
{
struct passwd *pw;
uid_t changeuid;
gid_t changegid;
/* uname might be a pointer returned from a previous called to getpw(),
** and libc has a problem getting it back.
*/
char *p=malloc(strlen(uname)+1);
if (!p)
{
perror("malloc");
exit(1);
}
strcpy(p, uname);
errno=ENOENT;
if ((pw=getpwnam(p)) == 0)
{
free(p);
perror("getpwnam");
exit(1);
}
free(p);
changeuid=pw->pw_uid;
if ( !forcegrp ) forcegrp= &pw->pw_gid;
changegid= *forcegrp;
if ( setgid( changegid ))
{
perror("setgid");
exit(1);
}
#if HAVE_INITGROUPS
if ( getuid() == 0 && initgroups(pw->pw_name, changegid) )
{
perror("initgroups");
exit(1);
}
#else
#if HAVE_SETGROUPS
if ( getuid() == 0 && setgroups(1, &changegid) )
{
perror("setgroups");
exit(1);
}
#endif
#endif
if (setuid(changeuid))
{
perror("setuid");
exit(1);
}
}
|
