diff options
Diffstat (limited to 'uidswap.c')
-rw-r--r-- | uidswap.c | 52 |
1 files changed, 49 insertions, 3 deletions
@@ -1,3 +1,4 @@ | |||
1 | /* $OpenBSD: uidswap.c,v 1.35 2006/08/03 03:34:42 deraadt Exp $ */ | ||
1 | /* | 2 | /* |
2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | 3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | 4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
@@ -12,7 +13,15 @@ | |||
12 | */ | 13 | */ |
13 | 14 | ||
14 | #include "includes.h" | 15 | #include "includes.h" |
15 | RCSID("$OpenBSD: uidswap.c,v 1.24 2003/05/29 16:58:45 deraadt Exp $"); | 16 | |
17 | #include <sys/param.h> | ||
18 | #include <errno.h> | ||
19 | #include <pwd.h> | ||
20 | #include <string.h> | ||
21 | #include <unistd.h> | ||
22 | #include <stdarg.h> | ||
23 | |||
24 | #include <grp.h> | ||
16 | 25 | ||
17 | #include "log.h" | 26 | #include "log.h" |
18 | #include "uidswap.h" | 27 | #include "uidswap.h" |
@@ -77,7 +86,7 @@ temporarily_use_uid(struct passwd *pw) | |||
77 | fatal("getgroups: %.100s", strerror(errno)); | 86 | fatal("getgroups: %.100s", strerror(errno)); |
78 | if (saved_egroupslen > 0) { | 87 | if (saved_egroupslen > 0) { |
79 | saved_egroups = xrealloc(saved_egroups, | 88 | saved_egroups = xrealloc(saved_egroups, |
80 | saved_egroupslen * sizeof(gid_t)); | 89 | saved_egroupslen, sizeof(gid_t)); |
81 | if (getgroups(saved_egroupslen, saved_egroups) < 0) | 90 | if (getgroups(saved_egroupslen, saved_egroups) < 0) |
82 | fatal("getgroups: %.100s", strerror(errno)); | 91 | fatal("getgroups: %.100s", strerror(errno)); |
83 | } else { /* saved_egroupslen == 0 */ | 92 | } else { /* saved_egroupslen == 0 */ |
@@ -96,7 +105,7 @@ temporarily_use_uid(struct passwd *pw) | |||
96 | fatal("getgroups: %.100s", strerror(errno)); | 105 | fatal("getgroups: %.100s", strerror(errno)); |
97 | if (user_groupslen > 0) { | 106 | if (user_groupslen > 0) { |
98 | user_groups = xrealloc(user_groups, | 107 | user_groups = xrealloc(user_groups, |
99 | user_groupslen * sizeof(gid_t)); | 108 | user_groupslen, sizeof(gid_t)); |
100 | if (getgroups(user_groupslen, user_groups) < 0) | 109 | if (getgroups(user_groupslen, user_groups) < 0) |
101 | fatal("getgroups: %.100s", strerror(errno)); | 110 | fatal("getgroups: %.100s", strerror(errno)); |
102 | } else { /* user_groupslen == 0 */ | 111 | } else { /* user_groupslen == 0 */ |
@@ -123,6 +132,41 @@ temporarily_use_uid(struct passwd *pw) | |||
123 | strerror(errno)); | 132 | strerror(errno)); |
124 | } | 133 | } |
125 | 134 | ||
135 | void | ||
136 | permanently_drop_suid(uid_t uid) | ||
137 | { | ||
138 | uid_t old_uid = getuid(); | ||
139 | |||
140 | debug("permanently_drop_suid: %u", (u_int)uid); | ||
141 | #if defined(HAVE_SETRESUID) && !defined(BROKEN_SETRESUID) | ||
142 | if (setresuid(uid, uid, uid) < 0) | ||
143 | fatal("setresuid %u: %.100s", (u_int)uid, strerror(errno)); | ||
144 | #elif defined(HAVE_SETREUID) && !defined(BROKEN_SETREUID) | ||
145 | if (setreuid(uid, uid) < 0) | ||
146 | fatal("setreuid %u: %.100s", (u_int)uid, strerror(errno)); | ||
147 | #else | ||
148 | # ifndef SETEUID_BREAKS_SETUID | ||
149 | if (seteuid(uid) < 0) | ||
150 | fatal("seteuid %u: %.100s", (u_int)uid, strerror(errno)); | ||
151 | # endif | ||
152 | if (setuid(uid) < 0) | ||
153 | fatal("setuid %u: %.100s", (u_int)uid, strerror(errno)); | ||
154 | #endif | ||
155 | |||
156 | #ifndef HAVE_CYGWIN | ||
157 | /* Try restoration of UID if changed (test clearing of saved uid) */ | ||
158 | if (old_uid != uid && | ||
159 | (setuid(old_uid) != -1 || seteuid(old_uid) != -1)) | ||
160 | fatal("%s: was able to restore old [e]uid", __func__); | ||
161 | #endif | ||
162 | |||
163 | /* Verify UID drop was successful */ | ||
164 | if (getuid() != uid || geteuid() != uid) { | ||
165 | fatal("%s: euid incorrect uid:%u euid:%u (should be %u)", | ||
166 | __func__, (u_int)getuid(), (u_int)geteuid(), (u_int)uid); | ||
167 | } | ||
168 | } | ||
169 | |||
126 | /* | 170 | /* |
127 | * Restores to the original (privileged) uid. | 171 | * Restores to the original (privileged) uid. |
128 | */ | 172 | */ |
@@ -169,6 +213,8 @@ permanently_set_uid(struct passwd *pw) | |||
169 | uid_t old_uid = getuid(); | 213 | uid_t old_uid = getuid(); |
170 | gid_t old_gid = getgid(); | 214 | gid_t old_gid = getgid(); |
171 | 215 | ||
216 | if (pw == NULL) | ||
217 | fatal("permanently_set_uid: no user given"); | ||
172 | if (temporarily_use_uid_effective) | 218 | if (temporarily_use_uid_effective) |
173 | fatal("permanently_set_uid: temporarily_use_uid effective"); | 219 | fatal("permanently_set_uid: temporarily_use_uid effective"); |
174 | debug("permanently_set_uid: %u/%u", (u_int)pw->pw_uid, | 220 | debug("permanently_set_uid: %u/%u", (u_int)pw->pw_uid, |