diff options
author | Colin Watson <cjwatson@debian.org> | 2014-10-07 13:33:15 +0100 |
---|---|---|
committer | Colin Watson <cjwatson@debian.org> | 2014-10-07 14:27:30 +0100 |
commit | f0b009aea83e9ff3a50be30f51012099a5143c16 (patch) | |
tree | 3825e6f7e3b7ea4481d06ed89aba9a7a95150df5 /bufbn.c | |
parent | 47f0bad4330b16ec3bad870fcf9839c196e42c12 (diff) | |
parent | 762c062828f5a8f6ed189ed6e44ad38fd92f8b36 (diff) |
Merge 6.7p1.
* New upstream release (http://www.openssh.com/txt/release-6.7):
- sshd(8): The default set of ciphers and MACs has been altered to
remove unsafe algorithms. In particular, CBC ciphers and arcfour* are
disabled by default. The full set of algorithms remains available if
configured explicitly via the Ciphers and MACs sshd_config options.
- ssh(1), sshd(8): Add support for Unix domain socket forwarding. A
remote TCP port may be forwarded to a local Unix domain socket and
vice versa or both ends may be a Unix domain socket (closes: #236718).
- ssh(1), ssh-keygen(1): Add support for SSHFP DNS records for ED25519
key types.
- sftp(1): Allow resumption of interrupted uploads.
- ssh(1): When rekeying, skip file/DNS lookups of the hostkey if it is
the same as the one sent during initial key exchange.
- sshd(8): Allow explicit ::1 and 127.0.0.1 forwarding bind addresses
when GatewayPorts=no; allows client to choose address family.
- sshd(8): Add a sshd_config PermitUserRC option to control whether
~/.ssh/rc is executed, mirroring the no-user-rc authorized_keys
option.
- ssh(1): Add a %C escape sequence for LocalCommand and ControlPath that
expands to a unique identifer based on a hash of the tuple of (local
host, remote user, hostname, port). Helps avoid exceeding miserly
pathname limits for Unix domain sockets in multiplexing control paths.
- sshd(8): Make the "Too many authentication failures" message include
the user, source address, port and protocol in a format similar to the
authentication success / failure messages.
- Use CLOCK_BOOTTIME in preference to CLOCK_MONOTONIC when it is
available. It considers time spent suspended, thereby ensuring
timeouts (e.g. for expiring agent keys) fire correctly (closes:
#734553).
- Use prctl() to prevent sftp-server from accessing
/proc/self/{mem,maps}.
* Restore TCP wrappers support, removed upstream in 6.7. It is true that
dropping this reduces preauth attack surface in sshd. On the other
hand, this support seems to be quite widely used, and abruptly dropping
it (from the perspective of users who don't read openssh-unix-dev) could
easily cause more serious problems in practice. It's not entirely clear
what the right long-term answer for Debian is, but it at least probably
doesn't involve dropping this feature shortly before a freeze.
* Replace patch to disable OpenSSL version check with an updated version
of Kurt Roeckx's patch from #732940 to just avoid checking the status
field.
Diffstat (limited to 'bufbn.c')
-rw-r--r-- | bufbn.c | 210 |
1 files changed, 42 insertions, 168 deletions
@@ -1,229 +1,103 @@ | |||
1 | /* $OpenBSD: bufbn.c,v 1.11 2014/02/27 08:25:09 djm Exp $*/ | 1 | /* $OpenBSD: bufbn.c,v 1.12 2014/04/30 05:29:56 djm Exp $ */ |
2 | |||
2 | /* | 3 | /* |
3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | 4 | * Copyright (c) 2012 Damien Miller <djm@mindrot.org> |
4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | ||
5 | * All rights reserved | ||
6 | * Auxiliary functions for storing and retrieving various data types to/from | ||
7 | * Buffers. | ||
8 | * | ||
9 | * As far as I am concerned, the code I have written for this software | ||
10 | * can be used freely for any purpose. Any derived versions of this | ||
11 | * software must be clearly marked as such, and if the derived work is | ||
12 | * incompatible with the protocol description in the RFC file, it must be | ||
13 | * called by a name other than "ssh" or "Secure Shell". | ||
14 | * | ||
15 | * | ||
16 | * SSH2 packet format added by Markus Friedl | ||
17 | * Copyright (c) 2000 Markus Friedl. All rights reserved. | ||
18 | * | 5 | * |
19 | * Redistribution and use in source and binary forms, with or without | 6 | * Permission to use, copy, modify, and distribute this software for any |
20 | * modification, are permitted provided that the following conditions | 7 | * purpose with or without fee is hereby granted, provided that the above |
21 | * are met: | 8 | * copyright notice and this permission notice appear in all copies. |
22 | * 1. Redistributions of source code must retain the above copyright | ||
23 | * notice, this list of conditions and the following disclaimer. | ||
24 | * 2. Redistributions in binary form must reproduce the above copyright | ||
25 | * notice, this list of conditions and the following disclaimer in the | ||
26 | * documentation and/or other materials provided with the distribution. | ||
27 | * | 9 | * |
28 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | 10 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
29 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | 11 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
30 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | 12 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
31 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | 13 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
32 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | 14 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
33 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | 15 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
34 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | 16 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
35 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | ||
36 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | ||
37 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
38 | */ | 17 | */ |
39 | 18 | ||
19 | /* Emulation wrappers for legacy OpenSSH buffer API atop sshbuf */ | ||
20 | |||
40 | #include "includes.h" | 21 | #include "includes.h" |
41 | 22 | ||
42 | #include <sys/types.h> | 23 | #include <sys/types.h> |
43 | 24 | ||
44 | #include <openssl/bn.h> | ||
45 | |||
46 | #include <string.h> | ||
47 | #include <stdarg.h> | ||
48 | #include <stdlib.h> | ||
49 | |||
50 | #include "xmalloc.h" | ||
51 | #include "buffer.h" | 25 | #include "buffer.h" |
52 | #include "log.h" | 26 | #include "log.h" |
53 | #include "misc.h" | 27 | #include "ssherr.h" |
54 | 28 | ||
55 | /* | ||
56 | * Stores an BIGNUM in the buffer with a 2-byte msb first bit count, followed | ||
57 | * by (bits+7)/8 bytes of binary data, msb first. | ||
58 | */ | ||
59 | int | 29 | int |
60 | buffer_put_bignum_ret(Buffer *buffer, const BIGNUM *value) | 30 | buffer_put_bignum_ret(Buffer *buffer, const BIGNUM *value) |
61 | { | 31 | { |
62 | int bits = BN_num_bits(value); | 32 | int ret; |
63 | int bin_size = (bits + 7) / 8; | ||
64 | u_char *buf = xmalloc(bin_size); | ||
65 | int oi; | ||
66 | char msg[2]; | ||
67 | |||
68 | /* Get the value of in binary */ | ||
69 | oi = BN_bn2bin(value, buf); | ||
70 | if (oi != bin_size) { | ||
71 | error("buffer_put_bignum_ret: BN_bn2bin() failed: oi %d != bin_size %d", | ||
72 | oi, bin_size); | ||
73 | free(buf); | ||
74 | return (-1); | ||
75 | } | ||
76 | |||
77 | /* Store the number of bits in the buffer in two bytes, msb first. */ | ||
78 | put_u16(msg, bits); | ||
79 | buffer_append(buffer, msg, 2); | ||
80 | /* Store the binary data. */ | ||
81 | buffer_append(buffer, buf, oi); | ||
82 | |||
83 | explicit_bzero(buf, bin_size); | ||
84 | free(buf); | ||
85 | 33 | ||
86 | return (0); | 34 | if ((ret = sshbuf_put_bignum1(buffer, value)) != 0) { |
35 | error("%s: %s", __func__, ssh_err(ret)); | ||
36 | return -1; | ||
37 | } | ||
38 | return 0; | ||
87 | } | 39 | } |
88 | 40 | ||
89 | void | 41 | void |
90 | buffer_put_bignum(Buffer *buffer, const BIGNUM *value) | 42 | buffer_put_bignum(Buffer *buffer, const BIGNUM *value) |
91 | { | 43 | { |
92 | if (buffer_put_bignum_ret(buffer, value) == -1) | 44 | if (buffer_put_bignum_ret(buffer, value) == -1) |
93 | fatal("buffer_put_bignum: buffer error"); | 45 | fatal("%s: buffer error", __func__); |
94 | } | 46 | } |
95 | 47 | ||
96 | /* | ||
97 | * Retrieves a BIGNUM from the buffer. | ||
98 | */ | ||
99 | int | 48 | int |
100 | buffer_get_bignum_ret(Buffer *buffer, BIGNUM *value) | 49 | buffer_get_bignum_ret(Buffer *buffer, BIGNUM *value) |
101 | { | 50 | { |
102 | u_int bits, bytes; | 51 | int ret; |
103 | u_char buf[2], *bin; | ||
104 | 52 | ||
105 | /* Get the number of bits. */ | 53 | if ((ret = sshbuf_get_bignum1(buffer, value)) != 0) { |
106 | if (buffer_get_ret(buffer, (char *) buf, 2) == -1) { | 54 | error("%s: %s", __func__, ssh_err(ret)); |
107 | error("buffer_get_bignum_ret: invalid length"); | 55 | return -1; |
108 | return (-1); | ||
109 | } | 56 | } |
110 | bits = get_u16(buf); | 57 | return 0; |
111 | if (bits > 65535-7) { | ||
112 | error("buffer_get_bignum_ret: cannot handle BN of size %d", | ||
113 | bits); | ||
114 | return (-1); | ||
115 | } | ||
116 | /* Compute the number of binary bytes that follow. */ | ||
117 | bytes = (bits + 7) / 8; | ||
118 | if (bytes > 8 * 1024) { | ||
119 | error("buffer_get_bignum_ret: cannot handle BN of size %d", bytes); | ||
120 | return (-1); | ||
121 | } | ||
122 | if (buffer_len(buffer) < bytes) { | ||
123 | error("buffer_get_bignum_ret: input buffer too small"); | ||
124 | return (-1); | ||
125 | } | ||
126 | bin = buffer_ptr(buffer); | ||
127 | if (BN_bin2bn(bin, bytes, value) == NULL) { | ||
128 | error("buffer_get_bignum_ret: BN_bin2bn failed"); | ||
129 | return (-1); | ||
130 | } | ||
131 | if (buffer_consume_ret(buffer, bytes) == -1) { | ||
132 | error("buffer_get_bignum_ret: buffer_consume failed"); | ||
133 | return (-1); | ||
134 | } | ||
135 | return (0); | ||
136 | } | 58 | } |
137 | 59 | ||
138 | void | 60 | void |
139 | buffer_get_bignum(Buffer *buffer, BIGNUM *value) | 61 | buffer_get_bignum(Buffer *buffer, BIGNUM *value) |
140 | { | 62 | { |
141 | if (buffer_get_bignum_ret(buffer, value) == -1) | 63 | if (buffer_get_bignum_ret(buffer, value) == -1) |
142 | fatal("buffer_get_bignum: buffer error"); | 64 | fatal("%s: buffer error", __func__); |
143 | } | 65 | } |
144 | 66 | ||
145 | /* | ||
146 | * Stores a BIGNUM in the buffer in SSH2 format. | ||
147 | */ | ||
148 | int | 67 | int |
149 | buffer_put_bignum2_ret(Buffer *buffer, const BIGNUM *value) | 68 | buffer_put_bignum2_ret(Buffer *buffer, const BIGNUM *value) |
150 | { | 69 | { |
151 | u_int bytes; | 70 | int ret; |
152 | u_char *buf; | 71 | |
153 | int oi; | 72 | if ((ret = sshbuf_put_bignum2(buffer, value)) != 0) { |
154 | u_int hasnohigh = 0; | 73 | error("%s: %s", __func__, ssh_err(ret)); |
155 | 74 | return -1; | |
156 | if (BN_is_zero(value)) { | ||
157 | buffer_put_int(buffer, 0); | ||
158 | return 0; | ||
159 | } | ||
160 | if (value->neg) { | ||
161 | error("buffer_put_bignum2_ret: negative numbers not supported"); | ||
162 | return (-1); | ||
163 | } | ||
164 | bytes = BN_num_bytes(value) + 1; /* extra padding byte */ | ||
165 | if (bytes < 2) { | ||
166 | error("buffer_put_bignum2_ret: BN too small"); | ||
167 | return (-1); | ||
168 | } | ||
169 | buf = xmalloc(bytes); | ||
170 | buf[0] = 0x00; | ||
171 | /* Get the value of in binary */ | ||
172 | oi = BN_bn2bin(value, buf+1); | ||
173 | if (oi < 0 || (u_int)oi != bytes - 1) { | ||
174 | error("buffer_put_bignum2_ret: BN_bn2bin() failed: " | ||
175 | "oi %d != bin_size %d", oi, bytes); | ||
176 | free(buf); | ||
177 | return (-1); | ||
178 | } | 75 | } |
179 | hasnohigh = (buf[1] & 0x80) ? 0 : 1; | 76 | return 0; |
180 | buffer_put_string(buffer, buf+hasnohigh, bytes-hasnohigh); | ||
181 | explicit_bzero(buf, bytes); | ||
182 | free(buf); | ||
183 | return (0); | ||
184 | } | 77 | } |
185 | 78 | ||
186 | void | 79 | void |
187 | buffer_put_bignum2(Buffer *buffer, const BIGNUM *value) | 80 | buffer_put_bignum2(Buffer *buffer, const BIGNUM *value) |
188 | { | 81 | { |
189 | if (buffer_put_bignum2_ret(buffer, value) == -1) | 82 | if (buffer_put_bignum2_ret(buffer, value) == -1) |
190 | fatal("buffer_put_bignum2: buffer error"); | 83 | fatal("%s: buffer error", __func__); |
191 | } | 84 | } |
192 | 85 | ||
193 | int | 86 | int |
194 | buffer_get_bignum2_ret(Buffer *buffer, BIGNUM *value) | 87 | buffer_get_bignum2_ret(Buffer *buffer, BIGNUM *value) |
195 | { | 88 | { |
196 | u_int len; | 89 | int ret; |
197 | u_char *bin; | ||
198 | 90 | ||
199 | if ((bin = buffer_get_string_ret(buffer, &len)) == NULL) { | 91 | if ((ret = sshbuf_get_bignum2(buffer, value)) != 0) { |
200 | error("buffer_get_bignum2_ret: invalid bignum"); | 92 | error("%s: %s", __func__, ssh_err(ret)); |
201 | return (-1); | 93 | return -1; |
202 | } | ||
203 | |||
204 | if (len > 0 && (bin[0] & 0x80)) { | ||
205 | error("buffer_get_bignum2_ret: negative numbers not supported"); | ||
206 | free(bin); | ||
207 | return (-1); | ||
208 | } | ||
209 | if (len > 8 * 1024) { | ||
210 | error("buffer_get_bignum2_ret: cannot handle BN of size %d", | ||
211 | len); | ||
212 | free(bin); | ||
213 | return (-1); | ||
214 | } | ||
215 | if (BN_bin2bn(bin, len, value) == NULL) { | ||
216 | error("buffer_get_bignum2_ret: BN_bin2bn failed"); | ||
217 | free(bin); | ||
218 | return (-1); | ||
219 | } | 94 | } |
220 | free(bin); | 95 | return 0; |
221 | return (0); | ||
222 | } | 96 | } |
223 | 97 | ||
224 | void | 98 | void |
225 | buffer_get_bignum2(Buffer *buffer, BIGNUM *value) | 99 | buffer_get_bignum2(Buffer *buffer, BIGNUM *value) |
226 | { | 100 | { |
227 | if (buffer_get_bignum2_ret(buffer, value) == -1) | 101 | if (buffer_get_bignum2_ret(buffer, value) == -1) |
228 | fatal("buffer_get_bignum2: buffer error"); | 102 | fatal("%s: buffer error", __func__); |
229 | } | 103 | } |