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
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/* ISC license. */
#include <string.h>
#include <pwd.h>
#include <grp.h>
#include <limits.h>
#include <skalibs/types.h>
#include <skalibs/sgetopt.h>
#include <skalibs/strerr2.h>
#include <skalibs/env.h>
#include <skalibs/djbunix.h>
#define USAGE "s6-envuidgid [ -i | -D defaultuid:defaultgid ] [ -u | -g | -B ] [ -n ] account prog..."
#define dieusage() strerr_dieusage(100, USAGE)
static inline size_t scan_defaults (char const *s, uid_t *uid, gid_t *gid, size_t *n, gid_t *tab)
{
size_t pos = uid_scan(s, uid) ;
if (!pos)
{
if (*s != ':') return 0 ;
*uid = 0 ;
}
s += pos ;
if (!*s) goto zgid ;
if (*s++ != ':') return 0 ;
if (!*s) goto zgid ;
pos = gid_scan(s, gid) ;
if (!pos)
{
if (*s != ':') return 0 ;
*gid = 0 ;
}
s += pos ;
if (!*s) goto zn ;
if (*s++ != ':') return 0 ;
if (!*s) goto zn ;
return gid_scanlist(tab, NGROUPS_MAX, s, n) ;
zgid:
*gid = 0 ;
zn:
*n = 0 ;
return 1 ;
}
int main (int argc, char *const *argv, char const *const *envp)
{
char const *user = 0 ;
char const *group = 0 ;
unsigned int what = 7 ;
int numfallback = 0 ;
int insist = 1 ;
uid_t uid ;
gid_t gid ;
size_t n ;
gid_t tab[NGROUPS_MAX] ;
PROG = "s6-envuidgid" ;
{
subgetopt_t l = SUBGETOPT_ZERO ;
for (;;)
{
int opt = subgetopt_r(argc, (char const *const *)argv, "ugBniD:", &l) ;
if (opt == -1) break ;
switch (opt)
{
case 'u' : what = 1 ; break ;
case 'g' : what = 2 ; break ;
case 'B' : what = 3 ; break ;
case 'n' : what &= 3 ; numfallback = 1 ; break ;
case 'i' : insist = 1 ; break ;
case 'D' :
if (!scan_defaults(l.arg, &uid, &gid, &n, tab)) dieusage() ;
insist = 0 ;
break ;
default : dieusage() ;
}
}
argc -= l.ind ; argv += l.ind ;
}
if (argc < 2) dieusage() ;
switch (what)
{
case 7 : /* account */
case 1 : /* user */
user = argv[0] ;
break ;
case 2 : /* group */
group = argv[0] ;
break ;
case 3 : /* both */
{
char *colon = strchr(argv[0], ':') ;
user = argv[0] ;
if (colon)
{
*colon = 0 ;
group = colon + 1 ;
if (colon == argv[0]) user = 0 ;
if (!group[0]) group = 0 ;
}
break ;
}
default : strerr_dief1x(101, "inconsistent option management - please submit a bug-report") ;
}
if (group)
{
struct group *gr = getgrnam(group) ;
if (gr) gid = gr->gr_gid ;
else if (numfallback && gid_scan(group, &gid)) ;
else if (insist) strerr_dief2x(1, "unknown group: ", group) ;
}
if (user)
{
struct passwd *pw = getpwnam(user) ;
if (pw)
{
uid = pw->pw_uid ;
if (what == 7)
{
int r = prot_readgroups(argv[0], tab, NGROUPS_MAX) ;
if (r < 0)
strerr_diefu2sys(111, "get supplementary groups for ", argv[0]) ;
n = r ;
gid = pw->pw_gid ;
}
}
else if (numfallback && uid_scan(user, &uid)) ;
else if (insist) strerr_dief2x(1, "unknown user: ", user) ;
}
{
size_t pos = 0 ;
char fmt[19 + UID_FMT + (NGROUPS_MAX+1) * GID_FMT] ;
if (what & 1)
{
memcpy(fmt + pos, "UID=", 4) ; pos += 4 ;
pos += uid_fmt(fmt + pos, uid) ;
fmt[pos++] = 0 ;
}
if (what & 2)
{
memcpy(fmt + pos, "GID=", 4) ; pos += 4 ;
pos += gid_fmt(fmt + pos, gid) ;
fmt[pos++] = 0 ;
}
if (what & 4)
{
memcpy(fmt + pos, "GIDLIST=", 8) ; pos += 8 ;
pos += gid_fmtlist(fmt + pos, tab, n) ;
fmt[pos++] = 0 ;
}
pathexec_r((char const *const *)argv + 1, envp, env_len(envp), fmt, pos) ;
}
strerr_dieexec(111, argv[1]) ;
}
|
