dropbear: svr-kex.c annotate

annotate svr-kex.c @ 1861:2b3a8026a6ce

Add re-exec for server This allows ASLR to re-randomize the address space for every connection, preventing some vulnerabilities from being exploitable by repeated probing. Overhead (memory and time) is yet to be confirmed. At present this is only enabled on Linux. Other BSD platforms with fexecve() would probably also work though have not been tested.

author	Matt Johnston <matt@ucc.asn.au>
date	Sun, 30 Jan 2022 10:14:56 +0800
parents	435cfb9ec96e
children	284c3837891c

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);
1681 435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	41 #if DROPBEAR_EXT_INFO
435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	42 static void send_msg_ext_info(void);
435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	43 #endif
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	44
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	45 /* 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	46 * 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	47 * 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	48 * 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	49 void recv_msg_kexdh_init() {
84 29a5c7c62350 default initialisers for mp_ints Matt Johnston <matt@ucc.asn.au> parents: 74 diff changeset	50 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	51 buffer *ecdh_qs = NULL;
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	52
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	53 TRACE(("enter recv_msg_kexdh_init"))
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	54 if (!ses.kexstate.recvkexinit) {
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	55 dropbear_exit("Premature kexdh_init message received");
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	56 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	57
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	58 switch (ses.newkeys->algo_kex->mode) {
1294 56aba7dedbea options for disabling "normal" DH Matt Johnston <matt@ucc.asn.au> parents: 1260 diff changeset	59 #if DROPBEAR_NORMAL_DH
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	60 case DROPBEAR_KEX_NORMAL_DH:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	61 m_mp_init(&dh_e);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	62 if (buf_getmpint(ses.payload, &dh_e) != DROPBEAR_SUCCESS) {
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	63 dropbear_exit("Bad kex value");
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	64 }
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	65 break;
1294 56aba7dedbea options for disabling "normal" DH Matt Johnston <matt@ucc.asn.au> parents: 1260 diff changeset	66 #endif
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	67 #if DROPBEAR_ECDH
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	68 case DROPBEAR_KEX_ECDH:
1294 56aba7dedbea options for disabling "normal" DH Matt Johnston <matt@ucc.asn.au> parents: 1260 diff changeset	69 #endif
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	70 #if DROPBEAR_CURVE25519
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	71 case DROPBEAR_KEX_CURVE25519:
1294 56aba7dedbea options for disabling "normal" DH Matt Johnston <matt@ucc.asn.au> parents: 1260 diff changeset	72 #endif
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	73 #if DROPBEAR_ECDH \|\| DROPBEAR_CURVE25519
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	74 ecdh_qs = buf_getstringbuf(ses.payload);
1294 56aba7dedbea options for disabling "normal" DH Matt Johnston <matt@ucc.asn.au> parents: 1260 diff changeset	75 break;
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	76 #endif
340 454a34b2dfd1 Fixes from Erik Hovland: Matt Johnston <matt@ucc.asn.au> parents: 165 diff changeset	77 }
852 7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	78 if (ses.payload->pos != ses.payload->len) {
7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	79 dropbear_exit("Bad kex value");
7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	80 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	81
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	82 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	83
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	84 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	85 if (ecdh_qs) {
b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	86 buf_free(ecdh_qs);
852 7540c0822374 Various cleanups and fixes for warnings Matt Johnston <matt@ucc.asn.au> parents: 850 diff changeset	87 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	88 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	89
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	90 send_msg_newkeys();
1678 4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	91
1681 435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	92 #if DROPBEAR_EXT_INFO
435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	93 /* Only send it following the first newkeys */
435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	94 if (!ses.kexstate.donesecondkex && ses.allow_ext_info) {
1678 4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	95 send_msg_ext_info();
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	96 }
1681 435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	97 #endif
1678 4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	98
886 cbc73a5aefb0 requirenext doesn't need two values Matt Johnston <matt@ucc.asn.au> parents: 875 diff changeset	99 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	100 TRACE(("leave recv_msg_kexdh_init"))
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	101 }
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	102
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
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	104 #if 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	105
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	106 static void svr_ensure_hostkey() {
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	107
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	108 const char* fn = NULL;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	109 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	110 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	111 int ret = DROPBEAR_FAILURE;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	112
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	113 if (hostkey && *hostkey) {
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	114 return;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	115 }
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 switch (type)
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	118 {
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	119 #if DROPBEAR_RSA
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	120 case DROPBEAR_SIGNKEY_RSA:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	121 fn = RSA_PRIV_FILENAME;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	122 break;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	123 #endif
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	124 #if DROPBEAR_DSS
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	125 case DROPBEAR_SIGNKEY_DSS:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	126 fn = DSS_PRIV_FILENAME;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	127 break;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	128 #endif
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	129 #if DROPBEAR_ECDSA
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	130 case DROPBEAR_SIGNKEY_ECDSA_NISTP256:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	131 case DROPBEAR_SIGNKEY_ECDSA_NISTP384:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	132 case DROPBEAR_SIGNKEY_ECDSA_NISTP521:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	133 fn = ECDSA_PRIV_FILENAME;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	134 break;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	135 #endif
1659 d32bcb5c557d Add Ed25519 support (#91) Vladislav Grishenko <themiron@users.noreply.github.com> parents: 1558 diff changeset	136 #if DROPBEAR_ED25519
d32bcb5c557d Add Ed25519 support (#91) Vladislav Grishenko <themiron@users.noreply.github.com> parents: 1558 diff changeset	137 case DROPBEAR_SIGNKEY_ED25519:
d32bcb5c557d Add Ed25519 support (#91) Vladislav Grishenko <themiron@users.noreply.github.com> parents: 1558 diff changeset	138 fn = ED25519_PRIV_FILENAME;
d32bcb5c557d Add Ed25519 support (#91) Vladislav Grishenko <themiron@users.noreply.github.com> parents: 1558 diff changeset	139 break;
d32bcb5c557d Add Ed25519 support (#91) Vladislav Grishenko <themiron@users.noreply.github.com> parents: 1558 diff changeset	140 #endif
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	141 default:
1260 c8f52c19e949 assertion for case that shouldn't happen Matt Johnston <matt@ucc.asn.au> parents: 1122 diff changeset	142 dropbear_assert(0);
846 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
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	145 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	146 return;
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
1329 185c14fa504d Use atomic key generation in all cases Matt Johnston <matt@ucc.asn.au> parents: 1295 diff changeset	149 if (signkey_generate(type, 0, fn, 1) == DROPBEAR_FAILURE) {
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	150 goto out;
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	151 }
1329 185c14fa504d Use atomic key generation in all cases Matt Johnston <matt@ucc.asn.au> parents: 1295 diff changeset	152
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	153 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	154
875 6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	155 if (ret == DROPBEAR_SUCCESS) {
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	156 char *fp = NULL;
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	157 unsigned int len;
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	158 buffer *key_buf = buf_new(MAX_PUBKEY_SIZE);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	159 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	160 buf_setpos(key_buf, 4);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	161 len = key_buf->len - key_buf->pos;
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	162 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	163 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	164 fn, fp);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	165 m_free(fp);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	166 buf_free(key_buf);
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	167 }
6c7a15668d5a Log when generating a hostkey Matt Johnston <matt@ucc.asn.au> parents: 858 diff changeset	168
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	169 out:
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	170 if (ret == DROPBEAR_FAILURE)
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	171 {
847 f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	172 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	173 }
b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	174 }
847 f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	175 #endif
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	176
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	177 /* 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	178 * 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	179 * 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	180 * result is sent to the client.
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	181 *
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	182 * 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	183 * 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	184 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	185 TRACE(("enter send_msg_kexdh_reply"))
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	186
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	187 /* we can start creating the kexdh_reply packet */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	188 CHECKCLEARTOWRITE();
847 f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	189
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	190 #if DROPBEAR_DELAY_HOSTKEY
847 f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	191 if (svr_opts.delay_hostkey)
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	192 {
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	193 svr_ensure_hostkey();
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	194 }
f4bb964c8678 Add '-R' for delayed hostkey option Matt Johnston <matt@ucc.asn.au> parents: 846 diff changeset	195 #endif
846 b298bb438625 refactor key generation, make it generate as required. Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	196
1558 2f64cb3d3007 - #if not #ifdef for DROPBEAR_FUZZ Matt Johnston <matt@ucc.asn.au> parents: 1456 diff changeset	197 #if DROPBEAR_FUZZ
1456 a90fdd2d2ed8 add fuzzer-preauth_nomaths Matt Johnston <matt@ucc.asn.au> parents: 1343 diff changeset	198 if (fuzz.fuzzing && fuzz.skip_kexmaths) {
a90fdd2d2ed8 add fuzzer-preauth_nomaths Matt Johnston <matt@ucc.asn.au> parents: 1343 diff changeset	199 fuzz_fake_send_kexdh_reply();
a90fdd2d2ed8 add fuzzer-preauth_nomaths Matt Johnston <matt@ucc.asn.au> parents: 1343 diff changeset	200 return;
a90fdd2d2ed8 add fuzzer-preauth_nomaths Matt Johnston <matt@ucc.asn.au> parents: 1343 diff changeset	201 }
a90fdd2d2ed8 add fuzzer-preauth_nomaths Matt Johnston <matt@ucc.asn.au> parents: 1343 diff changeset	202 #endif
a90fdd2d2ed8 add fuzzer-preauth_nomaths Matt Johnston <matt@ucc.asn.au> parents: 1343 diff changeset	203
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	204 buf_putbyte(ses.writepayload, SSH_MSG_KEXDH_REPLY);
24 469950e86d0f switching to global vars Matt Johnston <matt@ucc.asn.au> parents: 22 diff changeset	205 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	206 ses.newkeys->algo_hostkey);
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	207
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	208 switch (ses.newkeys->algo_kex->mode) {
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	209 #if DROPBEAR_NORMAL_DH
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	210 case DROPBEAR_KEX_NORMAL_DH:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	211 {
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	212 struct kex_dh_param * dh_param = gen_kexdh_param();
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	213 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	214
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	215 /* put f */
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	216 buf_putmpint(ses.writepayload, &dh_param->pub);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	217 free_kexdh_param(dh_param);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	218 }
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	219 break;
1294 56aba7dedbea options for disabling "normal" DH Matt Johnston <matt@ucc.asn.au> parents: 1260 diff changeset	220 #endif
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	221 #if DROPBEAR_ECDH
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	222 case DROPBEAR_KEX_ECDH:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	223 {
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	224 struct kex_ecdh_param *ecdh_param = gen_kexecdh_param();
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	225 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	226
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	227 buf_put_ecc_raw_pubkey_string(ses.writepayload, &ecdh_param->key);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	228 free_kexecdh_param(ecdh_param);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	229 }
1294 56aba7dedbea options for disabling "normal" DH Matt Johnston <matt@ucc.asn.au> parents: 1260 diff changeset	230 break;
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	231 #endif
1295 750ec4ec4cbe Convert #ifdef to #if, other build changes Matt Johnston <matt@ucc.asn.au> parents: 1294 diff changeset	232 #if DROPBEAR_CURVE25519
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	233 case DROPBEAR_KEX_CURVE25519:
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	234 {
849 754d7bee1068 Merge Matt Johnston <matt@ucc.asn.au> parents: 848 847 diff changeset	235 struct kex_curve25519_param *param = gen_kexcurve25519_param();
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	236 kexcurve25519_comb_key(param, ecdh_qs, svr_opts.hostkey);
1659 d32bcb5c557d Add Ed25519 support (#91) Vladislav Grishenko <themiron@users.noreply.github.com> parents: 1558 diff changeset	237
d32bcb5c557d Add Ed25519 support (#91) Vladislav Grishenko <themiron@users.noreply.github.com> parents: 1558 diff changeset	238 buf_putstring(ses.writepayload, param->pub, CURVE25519_LEN);
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	239 free_kexcurve25519_param(param);
6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	240 }
1294 56aba7dedbea options for disabling "normal" DH Matt Johnston <matt@ucc.asn.au> parents: 1260 diff changeset	241 break;
848 6c69e7df3621 curve25519 Matt Johnston <matt@ucc.asn.au> parents: 801 diff changeset	242 #endif
755 b07eb3dc23ec refactor kexdh code a bit, start working on ecdh etc Matt Johnston <matt@ucc.asn.au> parents: 603 diff changeset	243 }
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	244
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	245 /* calc the signature */
24 469950e86d0f switching to global vars Matt Johnston <matt@ucc.asn.au> parents: 22 diff changeset	246 buf_put_sign(ses.writepayload, svr_opts.hostkey,
1674 ba6fc7afe1c5 use sigtype where appropriate Matt Johnston <matt@ucc.asn.au> parents: 1659 diff changeset	247 ses.newkeys->algo_signature, ses.hash);
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	248
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	249 /* the SSH_MSG_KEXDH_REPLY is done */
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	250 encrypt_packet();
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	251
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	252 TRACE(("leave send_msg_kexdh_reply"))
4 fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	253 }
fe6bca95afa7 Makefile.in contains updated files required Matt Johnston <matt@ucc.asn.au> parents: diff changeset	254
1681 435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	255 #if DROPBEAR_EXT_INFO
1678 4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	256 /* Only used for server-sig-algs on the server side */
1681 435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	257 static void send_msg_ext_info(void) {
1678 4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	258 TRACE(("enter send_msg_ext_info"))
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	259
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	260 buf_putbyte(ses.writepayload, SSH_MSG_EXT_INFO);
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	261 /* nr-extensions */
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	262 buf_putint(ses.writepayload, 1);
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	263
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	264 buf_putstring(ses.writepayload, SSH_SERVER_SIG_ALGS, strlen(SSH_SERVER_SIG_ALGS));
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	265 buf_put_algolist_all(ses.writepayload, sigalgs, 1);
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	266
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	267 encrypt_packet();
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	268
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	269 TRACE(("leave send_msg_ext_info"))
4b4cfc92c5b7 Make server send SSH_MSG_EXT_INFO Matt Johnston <matt@ucc.asn.au> parents: 1674 diff changeset	270 }
1681 435cfb9ec96e send and handle SSH_MSG_EXT_INFO only at the correct point Matt Johnston <matt@ucc.asn.au> parents: 1678 diff changeset	271 #endif

Mercurial > dropbear

annotate svr-kex.c @ 1861:2b3a8026a6ce