naddy@openbsd.org | 768405f | 2017-05-03 21:08:09 +0000 | [diff] [blame] | 1 | /* $OpenBSD: kex.h,v 1.82 2017/05/03 21:08:09 naddy Exp $ */ |
Ben Lindstrom | 36579d3 | 2001-01-29 07:39:26 +0000 | [diff] [blame] | 2 | |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 3 | /* |
Ben Lindstrom | 4469723 | 2001-07-04 03:32:30 +0000 | [diff] [blame] | 4 | * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that the following conditions |
| 8 | * are met: |
| 9 | * 1. Redistributions of source code must retain the above copyright |
| 10 | * notice, this list of conditions and the following disclaimer. |
| 11 | * 2. Redistributions in binary form must reproduce the above copyright |
| 12 | * notice, this list of conditions and the following disclaimer in the |
| 13 | * documentation and/or other materials provided with the distribution. |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 14 | * |
| 15 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 16 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 17 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 18 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 19 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 20 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 21 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 22 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 23 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 24 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 25 | */ |
| 26 | #ifndef KEX_H |
| 27 | #define KEX_H |
| 28 | |
markus@openbsd.org | 128343b | 2015-01-13 19:31:40 +0000 | [diff] [blame] | 29 | #include "mac.h" |
djm@openbsd.org | 1129dcf | 2015-01-15 09:40:00 +0000 | [diff] [blame] | 30 | #include "buffer.h" /* XXX for typedef */ |
| 31 | #include "key.h" /* XXX for typedef */ |
markus@openbsd.org | 128343b | 2015-01-13 19:31:40 +0000 | [diff] [blame] | 32 | |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 33 | #ifdef WITH_LEAKMALLOC |
| 34 | #include "leakmalloc.h" |
Darren Tucker | 8ccb739 | 2010-09-10 12:28:24 +1000 | [diff] [blame] | 35 | #endif |
Damien Miller | d8337c5 | 2006-07-24 14:14:19 +1000 | [diff] [blame] | 36 | |
Damien Miller | 773dda2 | 2015-01-30 23:10:17 +1100 | [diff] [blame] | 37 | #ifdef WITH_OPENSSL |
| 38 | # ifdef OPENSSL_HAS_ECC |
| 39 | # include <openssl/ec.h> |
| 40 | # else /* OPENSSL_HAS_ECC */ |
| 41 | # define EC_KEY void |
| 42 | # define EC_GROUP void |
| 43 | # define EC_POINT void |
| 44 | # endif /* OPENSSL_HAS_ECC */ |
| 45 | #else /* WITH_OPENSSL */ |
| 46 | # define EC_KEY void |
| 47 | # define EC_GROUP void |
| 48 | # define EC_POINT void |
| 49 | #endif /* WITH_OPENSSL */ |
| 50 | |
Darren Tucker | 5b48cdd | 2009-06-21 18:15:25 +1000 | [diff] [blame] | 51 | #define KEX_COOKIE_LEN 16 |
| 52 | |
djm@openbsd.org | b97739d | 2016-09-22 21:15:41 +0000 | [diff] [blame] | 53 | #define KEX_DH1 "diffie-hellman-group1-sha1" |
| 54 | #define KEX_DH14_SHA1 "diffie-hellman-group14-sha1" |
| 55 | #define KEX_DH14_SHA256 "diffie-hellman-group14-sha256" |
| 56 | #define KEX_DH16_SHA512 "diffie-hellman-group16-sha512" |
| 57 | #define KEX_DH18_SHA512 "diffie-hellman-group18-sha512" |
| 58 | #define KEX_DHGEX_SHA1 "diffie-hellman-group-exchange-sha1" |
| 59 | #define KEX_DHGEX_SHA256 "diffie-hellman-group-exchange-sha256" |
| 60 | #define KEX_ECDH_SHA2_NISTP256 "ecdh-sha2-nistp256" |
| 61 | #define KEX_ECDH_SHA2_NISTP384 "ecdh-sha2-nistp384" |
| 62 | #define KEX_ECDH_SHA2_NISTP521 "ecdh-sha2-nistp521" |
| 63 | #define KEX_CURVE25519_SHA256 "curve25519-sha256" |
| 64 | #define KEX_CURVE25519_SHA256_OLD "curve25519-sha256@libssh.org" |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 65 | |
Damien Miller | 9786e6e | 2005-07-26 21:54:56 +1000 | [diff] [blame] | 66 | #define COMP_NONE 0 |
djm@openbsd.org | b768915 | 2016-09-28 21:44:52 +0000 | [diff] [blame] | 67 | #define COMP_ZLIB 1 |
| 68 | #define COMP_DELAYED 2 |
Damien Miller | 9786e6e | 2005-07-26 21:54:56 +1000 | [diff] [blame] | 69 | |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 70 | #define CURVE25519_SIZE 32 |
| 71 | |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 72 | enum kex_init_proposals { |
| 73 | PROPOSAL_KEX_ALGS, |
| 74 | PROPOSAL_SERVER_HOST_KEY_ALGS, |
| 75 | PROPOSAL_ENC_ALGS_CTOS, |
| 76 | PROPOSAL_ENC_ALGS_STOC, |
| 77 | PROPOSAL_MAC_ALGS_CTOS, |
| 78 | PROPOSAL_MAC_ALGS_STOC, |
| 79 | PROPOSAL_COMP_ALGS_CTOS, |
| 80 | PROPOSAL_COMP_ALGS_STOC, |
| 81 | PROPOSAL_LANG_CTOS, |
| 82 | PROPOSAL_LANG_STOC, |
| 83 | PROPOSAL_MAX |
| 84 | }; |
| 85 | |
| 86 | enum kex_modes { |
| 87 | MODE_IN, |
| 88 | MODE_OUT, |
| 89 | MODE_MAX |
| 90 | }; |
| 91 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 92 | enum kex_exchange { |
Damien Miller | 8e7fb33 | 2003-02-24 12:03:03 +1100 | [diff] [blame] | 93 | KEX_DH_GRP1_SHA1, |
Damien Miller | f675fc4 | 2004-06-15 10:30:09 +1000 | [diff] [blame] | 94 | KEX_DH_GRP14_SHA1, |
djm@openbsd.org | 0e8eeec | 2016-05-02 10:26:04 +0000 | [diff] [blame] | 95 | KEX_DH_GRP14_SHA256, |
| 96 | KEX_DH_GRP16_SHA512, |
| 97 | KEX_DH_GRP18_SHA512, |
Damien Miller | 8e7fb33 | 2003-02-24 12:03:03 +1100 | [diff] [blame] | 98 | KEX_DH_GEX_SHA1, |
Damien Miller | a63128d | 2006-03-15 12:08:28 +1100 | [diff] [blame] | 99 | KEX_DH_GEX_SHA256, |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 100 | KEX_ECDH_SHA2, |
Damien Miller | 1e12426 | 2013-11-04 08:26:52 +1100 | [diff] [blame] | 101 | KEX_C25519_SHA256, |
Damien Miller | 8e7fb33 | 2003-02-24 12:03:03 +1100 | [diff] [blame] | 102 | KEX_MAX |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 103 | }; |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 104 | |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 105 | #define KEX_INIT_SENT 0x0001 |
| 106 | |
markus@openbsd.org | 091c302 | 2015-01-19 19:52:16 +0000 | [diff] [blame] | 107 | struct sshenc { |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 108 | char *name; |
markus@openbsd.org | 091c302 | 2015-01-19 19:52:16 +0000 | [diff] [blame] | 109 | const struct sshcipher *cipher; |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 110 | int enabled; |
Damien Miller | 963f6b2 | 2002-02-19 15:21:23 +1100 | [diff] [blame] | 111 | u_int key_len; |
Damien Miller | 1d75abf | 2013-01-09 16:12:19 +1100 | [diff] [blame] | 112 | u_int iv_len; |
Damien Miller | 963f6b2 | 2002-02-19 15:21:23 +1100 | [diff] [blame] | 113 | u_int block_size; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 114 | u_char *key; |
| 115 | u_char *iv; |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 116 | }; |
markus@openbsd.org | 091c302 | 2015-01-19 19:52:16 +0000 | [diff] [blame] | 117 | struct sshcomp { |
| 118 | u_int type; |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 119 | int enabled; |
| 120 | char *name; |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 121 | }; |
markus@openbsd.org | 091c302 | 2015-01-19 19:52:16 +0000 | [diff] [blame] | 122 | struct newkeys { |
| 123 | struct sshenc enc; |
| 124 | struct sshmac mac; |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 125 | struct sshcomp comp; |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 126 | }; |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 127 | |
| 128 | struct ssh; |
| 129 | |
markus@openbsd.org | 091c302 | 2015-01-19 19:52:16 +0000 | [diff] [blame] | 130 | struct kex { |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 131 | u_char *session_id; |
markus@openbsd.org | 091c302 | 2015-01-19 19:52:16 +0000 | [diff] [blame] | 132 | size_t session_id_len; |
| 133 | struct newkeys *newkeys[MODE_MAX]; |
Damien Miller | eccb9de | 2005-06-17 12:59:34 +1000 | [diff] [blame] | 134 | u_int we_need; |
Damien Miller | 76eea4a | 2014-01-26 09:37:25 +1100 | [diff] [blame] | 135 | u_int dh_need; |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 136 | int server; |
| 137 | char *name; |
markus@openbsd.org | 76c9fbb | 2015-12-04 16:41:28 +0000 | [diff] [blame] | 138 | char *hostkey_alg; |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 139 | int hostkey_type; |
djm@openbsd.org | 5104db7 | 2015-01-26 06:10:03 +0000 | [diff] [blame] | 140 | int hostkey_nid; |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 141 | u_int kex_type; |
markus@openbsd.org | 76c9fbb | 2015-12-04 16:41:28 +0000 | [diff] [blame] | 142 | int rsa_sha2; |
| 143 | int ext_info_c; |
markus@openbsd.org | 091c302 | 2015-01-19 19:52:16 +0000 | [diff] [blame] | 144 | struct sshbuf *my; |
| 145 | struct sshbuf *peer; |
Damien Miller | 97c91f6 | 2006-04-23 12:08:37 +1000 | [diff] [blame] | 146 | sig_atomic_t done; |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 147 | u_int flags; |
Damien Miller | b3051d0 | 2014-01-10 10:58:53 +1100 | [diff] [blame] | 148 | int hash_alg; |
Damien Miller | ea11119 | 2013-04-23 19:24:32 +1000 | [diff] [blame] | 149 | int ec_nid; |
Ben Lindstrom | 2d90e00 | 2001-04-04 02:00:54 +0000 | [diff] [blame] | 150 | char *client_version_string; |
| 151 | char *server_version_string; |
djm@openbsd.org | f319912 | 2015-07-29 04:43:06 +0000 | [diff] [blame] | 152 | char *failed_choice; |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 153 | int (*verify_host_key)(struct sshkey *, struct ssh *); |
djm@openbsd.org | 5104db7 | 2015-01-26 06:10:03 +0000 | [diff] [blame] | 154 | struct sshkey *(*load_host_public_key)(int, int, struct ssh *); |
| 155 | struct sshkey *(*load_host_private_key)(int, int, struct ssh *); |
djm@openbsd.org | 523463a | 2015-02-16 22:13:32 +0000 | [diff] [blame] | 156 | int (*host_key_index)(struct sshkey *, int, struct ssh *); |
markus@openbsd.org | 76c9fbb | 2015-12-04 16:41:28 +0000 | [diff] [blame] | 157 | int (*sign)(struct sshkey *, struct sshkey *, u_char **, size_t *, |
| 158 | const u_char *, size_t, const char *, u_int); |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 159 | int (*kex[KEX_MAX])(struct ssh *); |
| 160 | /* kex specific state */ |
| 161 | DH *dh; /* DH */ |
| 162 | u_int min, max, nbits; /* GEX */ |
| 163 | EC_KEY *ec_client_key; /* ECDH */ |
| 164 | const EC_GROUP *ec_group; /* ECDH */ |
| 165 | u_char c25519_client_key[CURVE25519_SIZE]; /* 25519 */ |
| 166 | u_char c25519_client_pubkey[CURVE25519_SIZE]; /* 25519 */ |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 167 | }; |
| 168 | |
Damien Miller | d5f62bf | 2010-09-24 22:11:14 +1000 | [diff] [blame] | 169 | int kex_names_valid(const char *); |
Damien Miller | 690d989 | 2013-11-08 12:16:49 +1100 | [diff] [blame] | 170 | char *kex_alg_list(char); |
djm@openbsd.org | f9eca24 | 2015-07-30 00:01:34 +0000 | [diff] [blame] | 171 | char *kex_names_cat(const char *, const char *); |
| 172 | int kex_assemble_names(const char *, char **); |
Damien Miller | d5f62bf | 2010-09-24 22:11:14 +1000 | [diff] [blame] | 173 | |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 174 | int kex_new(struct ssh *, char *[PROPOSAL_MAX], struct kex **); |
| 175 | int kex_setup(struct ssh *, char *[PROPOSAL_MAX]); |
| 176 | void kex_free_newkeys(struct newkeys *); |
| 177 | void kex_free(struct kex *); |
Ben Lindstrom | 238abf6 | 2001-04-04 17:52:53 +0000 | [diff] [blame] | 178 | |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 179 | int kex_buf2prop(struct sshbuf *, int *, char ***); |
| 180 | int kex_prop2buf(struct sshbuf *, char *proposal[PROPOSAL_MAX]); |
| 181 | void kex_prop_free(char **); |
| 182 | |
| 183 | int kex_send_kexinit(struct ssh *); |
markus@openbsd.org | 3fdc88a | 2015-01-19 20:07:45 +0000 | [diff] [blame] | 184 | int kex_input_kexinit(int, u_int32_t, void *); |
markus@openbsd.org | 76c9fbb | 2015-12-04 16:41:28 +0000 | [diff] [blame] | 185 | int kex_input_ext_info(int, u_int32_t, void *); |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 186 | int kex_derive_keys(struct ssh *, u_char *, u_int, const struct sshbuf *); |
| 187 | int kex_derive_keys_bn(struct ssh *, u_char *, u_int, const BIGNUM *); |
| 188 | int kex_send_newkeys(struct ssh *); |
djm@openbsd.org | 19bcf2e | 2016-02-08 10:57:07 +0000 | [diff] [blame] | 189 | int kex_start_rekex(struct ssh *); |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 190 | |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 191 | int kexdh_client(struct ssh *); |
| 192 | int kexdh_server(struct ssh *); |
| 193 | int kexgex_client(struct ssh *); |
| 194 | int kexgex_server(struct ssh *); |
| 195 | int kexecdh_client(struct ssh *); |
| 196 | int kexecdh_server(struct ssh *); |
| 197 | int kexc25519_client(struct ssh *); |
| 198 | int kexc25519_server(struct ssh *); |
Damien Miller | 8e7fb33 | 2003-02-24 12:03:03 +1100 | [diff] [blame] | 199 | |
djm@openbsd.org | 0e8eeec | 2016-05-02 10:26:04 +0000 | [diff] [blame] | 200 | int kex_dh_hash(int, const char *, const char *, |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 201 | const u_char *, size_t, const u_char *, size_t, const u_char *, size_t, |
| 202 | const BIGNUM *, const BIGNUM *, const BIGNUM *, u_char *, size_t *); |
Damien Miller | 1e12426 | 2013-11-04 08:26:52 +1100 | [diff] [blame] | 203 | |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 204 | int kexgex_hash(int, const char *, const char *, |
| 205 | const u_char *, size_t, const u_char *, size_t, const u_char *, size_t, |
| 206 | int, int, int, |
| 207 | const BIGNUM *, const BIGNUM *, const BIGNUM *, |
| 208 | const BIGNUM *, const BIGNUM *, |
| 209 | u_char *, size_t *); |
| 210 | |
| 211 | int kex_ecdh_hash(int, const EC_GROUP *, const char *, const char *, |
| 212 | const u_char *, size_t, const u_char *, size_t, const u_char *, size_t, |
| 213 | const EC_POINT *, const EC_POINT *, const BIGNUM *, u_char *, size_t *); |
| 214 | |
djm@openbsd.org | 1a31d02 | 2016-05-02 08:49:03 +0000 | [diff] [blame] | 215 | int kex_c25519_hash(int, const char *, const char *, |
| 216 | const u_char *, size_t, const u_char *, size_t, |
| 217 | const u_char *, size_t, const u_char *, const u_char *, |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 218 | const u_char *, size_t, u_char *, size_t *); |
| 219 | |
| 220 | void kexc25519_keygen(u_char key[CURVE25519_SIZE], u_char pub[CURVE25519_SIZE]) |
Damien Miller | 686c7d9 | 2014-05-15 14:37:03 +1000 | [diff] [blame] | 221 | __attribute__((__bounded__(__minbytes__, 1, CURVE25519_SIZE))) |
| 222 | __attribute__((__bounded__(__minbytes__, 2, CURVE25519_SIZE))); |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 223 | int kexc25519_shared_key(const u_char key[CURVE25519_SIZE], |
| 224 | const u_char pub[CURVE25519_SIZE], struct sshbuf *out) |
Damien Miller | 686c7d9 | 2014-05-15 14:37:03 +1000 | [diff] [blame] | 225 | __attribute__((__bounded__(__minbytes__, 1, CURVE25519_SIZE))) |
| 226 | __attribute__((__bounded__(__minbytes__, 2, CURVE25519_SIZE))); |
Damien Miller | 8e7fb33 | 2003-02-24 12:03:03 +1100 | [diff] [blame] | 227 | |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 228 | #if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH) |
Ben Lindstrom | 16ae3d0 | 2001-07-04 04:02:36 +0000 | [diff] [blame] | 229 | void dump_digest(char *, u_char *, int); |
Ben Lindstrom | 20d7c7b | 2001-04-04 01:56:17 +0000 | [diff] [blame] | 230 | #endif |
| 231 | |
Damien Miller | 773dda2 | 2015-01-30 23:10:17 +1100 | [diff] [blame] | 232 | #if !defined(WITH_OPENSSL) || !defined(OPENSSL_HAS_ECC) |
| 233 | # undef EC_KEY |
| 234 | # undef EC_GROUP |
| 235 | # undef EC_POINT |
| 236 | #endif |
| 237 | |
Damien Miller | 33b1356 | 2000-04-04 14:38:59 +1000 | [diff] [blame] | 238 | #endif |