dropbear: svr-kex.c annotate

annotate svr-kex.c @ 994:5c5ade336926

Prefer stronger algorithms in algorithm negotiation. Prefer diffie-hellman-group14-sha1 (2048 bit) over diffie-hellman-group1-sha1 (1024 bit). Due to meet-in-the-middle attacks the effective key length of three key 3DES is 112 bits. AES is stronger and faster then 3DES. Prefer to delay the start of compression until after authentication has completed. This avoids exposing compression code to attacks from unauthenticated users. (github pull request #9)

author	Fedor Brunner <fedor.brunner@azet.sk>
date	Fri, 23 Jan 2015 23:00:25 +0800
parents	2b62f26cf808
children	aaf576b27a10

rev	line source
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	1 /*
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	2 * Dropbear - a SSH2 server
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	3 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	4 * Copyright (c) 2002,2003 Matt Johnston
74 e3adf4cf5465 License boilerplate etc, add Mihnea as an author to some of the files Matt Johnston <matt@ucc.asn.au> parents: 26 diff changeset	5 * Copyright (c) 2004 by Mihnea Stoenescu
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	6 * All rights reserved.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	7 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	8 * Permission is hereby granted, free of charge, to any person obtaining a copy
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	9 * of this software and associated documentation files (the "Software"), to deal
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	10 * in the Software without restriction, including without limitation the rights
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	12 * copies of the Software, and to permit persons to whom the Software is
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	13 * furnished to do so, subject to the following conditions:
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	14 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	15 * The above copyright notice and this permission notice shall be included in
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	16 * all copies or substantial portions of the Software.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	17 *
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	24 * SOFTWARE. */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	25
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	26 #include "includes.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	27 #include "dbutil.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	28 #include "algo.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	29 #include "buffer.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	30 #include "session.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	31 #include "kex.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	32 #include "ssh.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	33 #include "packet.h"
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	34 #include "bignum.h"
858 220f55d540ae rename random.h to dbrandom.h since some OSes have a system random.h Matt Johnston <matt@ucc.asn.au> parents: 852 diff changeset	35 #include "dbrandom.h"
24 469950e86d0f switching to global vars Matt Johnston <matt@ucc.asn.au> parents: 22 diff changeset	36 #include "runopts.h"
761 ac2158e3e403 ecc kind of works, needs fixing/testing Matt Johnston <matt@ucc.asn.au> parents: 759 diff changeset	37 #include "ecc.h"
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	38 #include "gensignkey.h"
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	39
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	40 static void send_msg_kexdh_reply(mp_int dh_e, buffer ecdh_qs);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	41
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	42 /* Handle a diffie-hellman key exchange initialisation. This involves
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	43 * calculating a session key reply value, and corresponding hash. These
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	44 * are carried out by send_msg_kexdh_reply(). recv_msg_kexdh_init() calls
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	45 * that function, then brings the new keys into use */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	46 void recv_msg_kexdh_init() {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	47
84 29a5c7c62350 default initialisers for mp_ints Matt Johnston <matt@ucc.asn.au> parents: 74 diff changeset	48 DEF_MP_INT(dh_e);
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	49 buffer *ecdh_qs = NULL;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	50
165 0cfba3034be5 Fixed DEBUG_TRACE macro so that we don't get semicolons left about the place Matt Johnston <matt@ucc.asn.au> parents: 84 diff changeset	51 TRACE(("enter recv_msg_kexdh_init"))
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	52 if (!ses.kexstate.recvkexinit) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	53 dropbear_exit("Premature kexdh_init message received");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	54 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	55
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	56 switch (ses.newkeys->algo_kex->mode) {
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	57 case DROPBEAR_KEX_NORMAL_DH:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	58 m_mp_init(&dh_e);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	59 if (buf_getmpint(ses.payload, &dh_e) != DROPBEAR_SUCCESS) {
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	60 dropbear_exit("Bad kex value");
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	61 }
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	62 break;
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	63 case DROPBEAR_KEX_ECDH:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	64 case DROPBEAR_KEX_CURVE25519:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	65 #if defined(DROPBEAR_ECDH) \|\| defined(DROPBEAR_CURVE25519)
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	66 ecdh_qs = buf_getstringbuf(ses.payload);
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	67 #endif
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	68 break;
340 454a34b2dfd1 Fixes from Erik Hovland: Matt Johnston <matt@ucc.asn.au> parents: 165 diff changeset	69 }
852 7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	70 if (ses.payload->pos != ses.payload->len) {
7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	71 dropbear_exit("Bad kex value");
7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	72 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	73
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	74 send_msg_kexdh_reply(&dh_e, ecdh_qs);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	75
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	76 mp_clear(&dh_e);
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	77 if (ecdh_qs) {
b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	78 buf_free(ecdh_qs);
852 7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	79 ecdh_qs = NULL;
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	80 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	81
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	82 send_msg_newkeys();
886 cbc73a5aefb0 requirenext doesn't need two values Matt Johnston <matt@ucc.asn.au> parents: 875 diff changeset	83 ses.requirenext = SSH_MSG_NEWKEYS;
165 0cfba3034be5 Fixed DEBUG_TRACE macro so that we don't get semicolons left about the place Matt Johnston <matt@ucc.asn.au> parents: 84 diff changeset	84 TRACE(("leave recv_msg_kexdh_init"))
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	85 }
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	86
982 fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	87
847 f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	88 #ifdef DROPBEAR_DELAY_HOSTKEY
982 fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	89
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	90 static void fsync_parent_dir(const char* fn) {
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	91 #ifdef HAVE_LIBGEN_H
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	92 char *fn_dir = m_strdup(fn);
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	93 char *dir = dirname(fn_dir);
983 2b62f26cf808 Open directories O_RDONLY for fsync, add debugging if it fails Matt Johnston <matt@ucc.asn.au> parents: 982 diff changeset	94 int dirfd = open(dir, O_RDONLY);
982 fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	95
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	96 if (dirfd != -1) {
983 2b62f26cf808 Open directories O_RDONLY for fsync, add debugging if it fails Matt Johnston <matt@ucc.asn.au> parents: 982 diff changeset	97 if (fsync(dirfd) != 0) {
2b62f26cf808 Open directories O_RDONLY for fsync, add debugging if it fails Matt Johnston <matt@ucc.asn.au> parents: 982 diff changeset	98 TRACE(("fsync of directory %s failed: %s", dir, strerror(errno)))
2b62f26cf808 Open directories O_RDONLY for fsync, add debugging if it fails Matt Johnston <matt@ucc.asn.au> parents: 982 diff changeset	99 }
982 fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	100 m_close(dirfd);
983 2b62f26cf808 Open directories O_RDONLY for fsync, add debugging if it fails Matt Johnston <matt@ucc.asn.au> parents: 982 diff changeset	101 } else {
2b62f26cf808 Open directories O_RDONLY for fsync, add debugging if it fails Matt Johnston <matt@ucc.asn.au> parents: 982 diff changeset	102 TRACE(("error opening directory %s for fsync: %s", dir, strerror(errno)))
982 fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	103 }
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	104
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	105 free(fn_dir);
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	106 #endif
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	107 }
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	108
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	109 static void svr_ensure_hostkey() {
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	110
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	111 const char* fn = NULL;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	112 char *fn_temp = NULL;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	113 enum signkey_type type = ses.newkeys->algo_hostkey;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	114 void **hostkey = signkey_key_ptr(svr_opts.hostkey, type);
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	115 int ret = DROPBEAR_FAILURE;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	116
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	117 if (hostkey && *hostkey) {
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	118 return;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	119 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	120
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	121 switch (type)
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	122 {
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	123 #ifdef DROPBEAR_RSA
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	124 case DROPBEAR_SIGNKEY_RSA:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	125 fn = RSA_PRIV_FILENAME;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	126 break;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	127 #endif
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	128 #ifdef DROPBEAR_DSS
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	129 case DROPBEAR_SIGNKEY_DSS:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	130 fn = DSS_PRIV_FILENAME;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	131 break;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	132 #endif
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	133 #ifdef DROPBEAR_ECDSA
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	134 case DROPBEAR_SIGNKEY_ECDSA_NISTP256:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	135 case DROPBEAR_SIGNKEY_ECDSA_NISTP384:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	136 case DROPBEAR_SIGNKEY_ECDSA_NISTP521:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	137 fn = ECDSA_PRIV_FILENAME;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	138 break;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	139 #endif
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	140 default:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	141 (void)0;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	142 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	143
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	144 if (readhostkey(fn, svr_opts.hostkey, &type) == DROPBEAR_SUCCESS) {
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	145 return;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	146 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	147
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	148 fn_temp = m_malloc(strlen(fn) + 20);
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	149 snprintf(fn_temp, strlen(fn)+20, "%s.tmp%d", fn, getpid());
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	150
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	151 if (signkey_generate(type, 0, fn_temp) == DROPBEAR_FAILURE) {
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	152 goto out;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	153 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	154
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	155 if (link(fn_temp, fn) < 0) {
852 7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	156 /* It's OK to get EEXIST - we probably just lost a race
7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	157 with another connection to generate the key */
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	158 if (errno != EEXIST) {
852 7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	159 dropbear_log(LOG_ERR, "Failed moving key file to %s: %s", fn,
7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	160 strerror(errno));
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	161 /* XXX fallback to non-atomic copy for some filesystems? */
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	162 goto out;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	163 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	164 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	165
982 fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	166 /* ensure directory update is flushed to disk, otherwise we can end up
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	167 with zero-byte hostkey files if the power goes off */
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	168 fsync_parent_dir(fn);
fd2e8bbb0333 Make sure hostkeys are flushed to disk to avoid empty files if the power Matt Johnston <matt@ucc.asn.au> parents: 886 diff changeset	169
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	170 ret = readhostkey(fn, svr_opts.hostkey, &type);
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	171
875 6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	172 if (ret == DROPBEAR_SUCCESS) {
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	173 char *fp = NULL;
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	174 unsigned int len;
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	175 buffer *key_buf = buf_new(MAX_PUBKEY_SIZE);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	176 buf_put_pub_key(key_buf, svr_opts.hostkey, type);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	177 buf_setpos(key_buf, 4);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	178 len = key_buf->len - key_buf->pos;
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	179 fp = sign_key_fingerprint(buf_getptr(key_buf, len), len);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	180 dropbear_log(LOG_INFO, "Generated hostkey %s, fingerprint is %s",
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	181 fn, fp);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	182 m_free(fp);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	183 buf_free(key_buf);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	184 }
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	185
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	186 out:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	187 if (fn_temp) {
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	188 unlink(fn_temp);
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	189 m_free(fn_temp);
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	190 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	191
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	192 if (ret == DROPBEAR_FAILURE)
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	193 {
847 f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	194 dropbear_exit("Couldn't read or generate hostkey %s", fn);
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	195 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	196 }
847 f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	197 #endif
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	198
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	199 /* Generate our side of the diffie-hellman key exchange value (dh_f), and
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	200 * calculate the session key using the diffie-hellman algorithm. Following
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	201 * that, the session hash is calculated, and signed with RSA or DSS. The
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	202 * result is sent to the client.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	203 *
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	204 * See the transport RFC4253 section 8 for details
b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	205 * or RFC5656 section 4 for elliptic curve variant. */
b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	206 static void send_msg_kexdh_reply(mp_int dh_e, buffer ecdh_qs) {
165 0cfba3034be5 Fixed DEBUG_TRACE macro so that we don't get semicolons left about the place Matt Johnston <matt@ucc.asn.au> parents: 84 diff changeset	207 TRACE(("enter send_msg_kexdh_reply"))
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	208
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	209 /* we can start creating the kexdh_reply packet */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	210 CHECKCLEARTOWRITE();
847 f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	211
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	212 #ifdef DROPBEAR_DELAY_HOSTKEY
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	213 if (svr_opts.delay_hostkey)
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	214 {
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	215 svr_ensure_hostkey();
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	216 }
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	217 #endif
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	218
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	219 buf_putbyte(ses.writepayload, SSH_MSG_KEXDH_REPLY);
24 469950e86d0f switching to global vars Matt Johnston <matt@ucc.asn.au> parents: 22 diff changeset	220 buf_put_pub_key(ses.writepayload, svr_opts.hostkey,
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	221 ses.newkeys->algo_hostkey);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	222
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	223 switch (ses.newkeys->algo_kex->mode) {
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	224 case DROPBEAR_KEX_NORMAL_DH:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	225 {
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	226 struct kex_dh_param * dh_param = gen_kexdh_param();
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	227 kexdh_comb_key(dh_param, dh_e, svr_opts.hostkey);
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	228
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	229 /* put f */
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	230 buf_putmpint(ses.writepayload, &dh_param->pub);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	231 free_kexdh_param(dh_param);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	232 }
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	233 break;
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	234 case DROPBEAR_KEX_ECDH:
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	235 #ifdef DROPBEAR_ECDH
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	236 {
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	237 struct kex_ecdh_param *ecdh_param = gen_kexecdh_param();
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	238 kexecdh_comb_key(ecdh_param, ecdh_qs, svr_opts.hostkey);
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	239
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	240 buf_put_ecc_raw_pubkey_string(ses.writepayload, &ecdh_param->key);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	241 free_kexecdh_param(ecdh_param);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	242 }
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	243 #endif
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	244 break;
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	245 case DROPBEAR_KEX_CURVE25519:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	246 #ifdef DROPBEAR_CURVE25519
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	247 {
849 754d7bee1068 Merge Matt Johnston <matt@ucc.asn.au> parents: 848 847 diff changeset	248 struct kex_curve25519_param *param = gen_kexcurve25519_param();
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	249 kexcurve25519_comb_key(param, ecdh_qs, svr_opts.hostkey);
850 7507b174bba0 - Make curve25519 work after fixing a typo, interoperates with OpenSSH Matt Johnston <matt@ucc.asn.au> parents: 849 diff changeset	250 buf_putstring(ses.writepayload, param->pub, CURVE25519_LEN);
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	251 free_kexcurve25519_param(param);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	252 }
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	253 #endif
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	254 break;
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	255 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	256
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	257 /* calc the signature */
24 469950e86d0f switching to global vars Matt Johnston <matt@ucc.asn.au> parents: 22 diff changeset	258 buf_put_sign(ses.writepayload, svr_opts.hostkey,
761 ac2158e3e403 ecc kind of works, needs fixing/testing Matt Johnston <matt@ucc.asn.au> parents: 759 diff changeset	259 ses.newkeys->algo_hostkey, ses.hash);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	260
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	261 /* the SSH_MSG_KEXDH_REPLY is done */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	262 encrypt_packet();
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	263
165 0cfba3034be5 Fixed DEBUG_TRACE macro so that we don't get semicolons left about the place Matt Johnston <matt@ucc.asn.au> parents: 84 diff changeset	264 TRACE(("leave send_msg_kexdh_reply"))
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	265 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	266

Mercurial > dropbear

annotate svr-kex.c @ 994:5c5ade336926