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authorColin Watson <cjwatson@debian.org>2007-06-12 16:16:35 +0000
committerColin Watson <cjwatson@debian.org>2007-06-12 16:16:35 +0000
commitb7e40fa9da0b5491534a429dadb321eab5a77558 (patch)
treebed1da11e9f829925797aa093e379fc0b5868ecd /uidswap.c
parent4f84beedf1005e44ff33c854abd6b711ffc0adb7 (diff)
parent086ea76990b1e6287c24b6db74adffd4605eb3b0 (diff)
* New upstream release (closes: #395507, #397961, #420035). Important
changes not previously backported to 4.3p2: - 4.4/4.4p1 (http://www.openssh.org/txt/release-4.4): + On portable OpenSSH, fix a GSSAPI authentication abort that could be used to determine the validity of usernames on some platforms. + Implemented conditional configuration in sshd_config(5) using the "Match" directive. This allows some configuration options to be selectively overridden if specific criteria (based on user, group, hostname and/or address) are met. So far a useful subset of post-authentication options are supported and more are expected to be added in future releases. + Add support for Diffie-Hellman group exchange key agreement with a final hash of SHA256. + Added a "ForceCommand" directive to sshd_config(5). Similar to the command="..." option accepted in ~/.ssh/authorized_keys, this forces the execution of the specified command regardless of what the user requested. This is very useful in conjunction with the new "Match" option. + Add a "PermitOpen" directive to sshd_config(5). This mirrors the permitopen="..." authorized_keys option, allowing fine-grained control over the port-forwardings that a user is allowed to establish. + Add optional logging of transactions to sftp-server(8). + ssh(1) will now record port numbers for hosts stored in ~/.ssh/known_hosts when a non-standard port has been requested (closes: #50612). + Add an "ExitOnForwardFailure" option to cause ssh(1) to exit (with a non-zero exit code) when requested port forwardings could not be established. + Extend sshd_config(5) "SubSystem" declarations to allow the specification of command-line arguments. + Replacement of all integer overflow susceptible invocations of malloc(3) and realloc(3) with overflow-checking equivalents. + Many manpage fixes and improvements. + Add optional support for OpenSSL hardware accelerators (engines), enabled using the --with-ssl-engine configure option. + Tokens in configuration files may be double-quoted in order to contain spaces (closes: #319639). + Move a debug() call out of a SIGCHLD handler, fixing a hang when the session exits very quickly (closes: #307890). + Fix some incorrect buffer allocation calculations (closes: #410599). + ssh-add doesn't ask for a passphrase if key file permissions are too liberal (closes: #103677). + Likewise, ssh doesn't ask either (closes: #99675). - 4.6/4.6p1 (http://www.openssh.org/txt/release-4.6): + sshd now allows the enabling and disabling of authentication methods on a per user, group, host and network basis via the Match directive in sshd_config. + Fixed an inconsistent check for a terminal when displaying scp progress meter (closes: #257524). + Fix "hang on exit" when background processes are running at the time of exit on a ttyful/login session (closes: #88337). * Update to current GSSAPI patch from http://www.sxw.org.uk/computing/patches/openssh-4.6p1-gsskex-20070312.patch; install ChangeLog.gssapi.
Diffstat (limited to 'uidswap.c')
-rw-r--r--uidswap.c52
1 files changed, 49 insertions, 3 deletions
diff --git a/uidswap.c b/uidswap.c
index aab7064eb..91d878c30 100644
--- a/uidswap.c
+++ b/uidswap.c
@@ -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"
15RCSID("$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
135void
136permanently_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,