diff options
author | Matt Johnston <matt@ucc.asn.au> | 2007-01-11 03:14:55 +0000 |
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committer | Matt Johnston <matt@ucc.asn.au> | 2007-01-11 03:14:55 +0000 |
commit | 9d5ed350a749368c84254c11e7616ce3c891193a (patch) | |
tree | 6dacbff2e9f5c60a1568382db55c72dd6d2ce925 /common-algo.c | |
parent | ca52f070aecf91e75f6ae6c87d4ae1a2189ccb14 (diff) | |
parent | 5ea605d8de5b4438deb4fa86c5231710dd09f934 (diff) |
propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 2af95f00ebd5bb7a28b3817db1218442c935388e)
to branch 'au.asn.ucc.matt.dropbear' (head ecd779509ef23a8cdf64888904fc9b31d78aa933)
--HG--
extra : convert_revision : d26d5eb2837f46b56a33fb0e7573aa0201abd4d5
Diffstat (limited to 'common-algo.c')
-rw-r--r-- | common-algo.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/common-algo.c b/common-algo.c new file mode 100644 index 0000000..ae2102a --- /dev/null +++ b/common-algo.c @@ -0,0 +1,228 @@ +/* + * Dropbear SSH + * + * Copyright (c) 2002,2003 Matt Johnston + * Copyright (c) 2004 by Mihnea Stoenescu + * All rights reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. */ + +#include "algo.h" +#include "dbutil.h" + +/* This file (algo.c) organises the ciphers which can be used, and is used to + * decide which ciphers/hashes/compression/signing to use during key exchange*/ + +/* Mappings for ciphers, parameters are + {&cipher_desc, keysize, blocksize} */ + +#ifdef DROPBEAR_AES256_CBC +static const struct dropbear_cipher dropbear_aes256 = + {&aes_desc, 32, 16}; +#endif +#ifdef DROPBEAR_AES128_CBC +static const struct dropbear_cipher dropbear_aes128 = + {&aes_desc, 16, 16}; +#endif +#ifdef DROPBEAR_BLOWFISH_CBC +static const struct dropbear_cipher dropbear_blowfish = + {&blowfish_desc, 16, 8}; +#endif +#ifdef DROPBEAR_TWOFISH256_CBC +static const struct dropbear_cipher dropbear_twofish256 = + {&twofish_desc, 32, 16}; +#endif +#ifdef DROPBEAR_TWOFISH128_CBC +static const struct dropbear_cipher dropbear_twofish128 = + {&twofish_desc, 16, 16}; +#endif +#ifdef DROPBEAR_3DES_CBC +static const struct dropbear_cipher dropbear_3des = + {&des3_desc, 24, 8}; +#endif + +/* used to indicate no encryption, as defined in rfc2410 */ +const struct dropbear_cipher dropbear_nocipher = + {NULL, 16, 8}; + +/* Mapping of ssh hashes to libtomcrypt hashes, including keysize etc. + {&hash_desc, keysize, hashsize} */ + +#ifdef DROPBEAR_SHA1_HMAC +static const struct dropbear_hash dropbear_sha1 = + {&sha1_desc, 20, 20}; +#endif +#ifdef DROPBEAR_SHA1_96_HMAC +static const struct dropbear_hash dropbear_sha1_96 = + {&sha1_desc, 20, 12}; +#endif +#ifdef DROPBEAR_MD5_HMAC +static const struct dropbear_hash dropbear_md5 = + {&md5_desc, 16, 16}; +#endif + +const struct dropbear_hash dropbear_nohash = + {NULL, 16, 0}; /* used initially */ + + +/* The following map ssh names to internal values */ + +algo_type sshciphers[] = { +#ifdef DROPBEAR_AES128_CBC + {"aes128-cbc", 0, (void*)&dropbear_aes128, 1}, +#endif +#ifdef DROPBEAR_3DES_CBC + {"3des-cbc", 0, (void*)&dropbear_3des, 1}, +#endif +#ifdef DROPBEAR_AES256_CBC + {"aes256-cbc", 0, (void*)&dropbear_aes256, 1}, +#endif +#ifdef DROPBEAR_TWOFISH256_CBC + {"twofish256-cbc", 0, (void*)&dropbear_twofish256, 1}, + {"twofish-cbc", 0, (void*)&dropbear_twofish256, 1}, +#endif +#ifdef DROPBEAR_TWOFISH128_CBC + {"twofish128-cbc", 0, (void*)&dropbear_twofish128, 1}, +#endif +#ifdef DROPBEAR_BLOWFISH_CBC + {"blowfish-cbc", 0, (void*)&dropbear_blowfish, 1}, +#endif + {NULL, 0, NULL, 0} +}; + +algo_type sshhashes[] = { +#ifdef DROPBEAR_SHA1_96_HMAC + {"hmac-sha1-96", 0, (void*)&dropbear_sha1_96, 1}, +#endif +#ifdef DROPBEAR_SHA1_HMAC + {"hmac-sha1", 0, (void*)&dropbear_sha1, 1}, +#endif +#ifdef DROPBEAR_MD5_HMAC + {"hmac-md5", 0, (void*)&dropbear_md5, 1}, +#endif + {NULL, 0, NULL, 0} +}; + +algo_type sshcompress[] = { +#ifndef DISABLE_ZLIB + {"zlib", DROPBEAR_COMP_ZLIB, NULL, 1}, +#endif + {"none", DROPBEAR_COMP_NONE, NULL, 1}, + {NULL, 0, NULL, 0} +}; + +algo_type sshhostkey[] = { +#ifdef DROPBEAR_RSA + {"ssh-rsa", DROPBEAR_SIGNKEY_RSA, NULL, 1}, +#endif +#ifdef DROPBEAR_DSS + {"ssh-dss", DROPBEAR_SIGNKEY_DSS, NULL, 1}, +#endif + {NULL, 0, NULL, 0} +}; + +algo_type sshkex[] = { + {"diffie-hellman-group1-sha1", DROPBEAR_KEX_DH_GROUP1, NULL, 1}, + {NULL, 0, NULL, 0} +}; + + +/* Register the compiled in ciphers. + * This should be run before using any of the ciphers/hashes */ +void crypto_init() { + + const struct ltc_cipher_descriptor *regciphers[] = { +#ifdef DROPBEAR_AES_CBC + &aes_desc, +#endif +#ifdef DROPBEAR_BLOWFISH_CBC + &blowfish_desc, +#endif +#ifdef DROPBEAR_TWOFISH_CBC + &twofish_desc, +#endif +#ifdef DROPBEAR_3DES_CBC + &des3_desc, +#endif + NULL + }; + + const struct ltc_hash_descriptor *reghashes[] = { + /* we need sha1 for hostkey stuff regardless */ + &sha1_desc, +#ifdef DROPBEAR_MD5_HMAC + &md5_desc, +#endif + NULL + }; + int i; + + for (i = 0; regciphers[i] != NULL; i++) { + if (register_cipher(regciphers[i]) == -1) { + dropbear_exit("error registering crypto"); + } + } + + for (i = 0; reghashes[i] != NULL; i++) { + if (register_hash(reghashes[i]) == -1) { + dropbear_exit("error registering crypto"); + } + } +} + +/* algolen specifies the length of algo, algos is our local list to match + * against. + * Returns DROPBEAR_SUCCESS if we have a match for algo, DROPBEAR_FAILURE + * otherwise */ +int have_algo(char* algo, size_t algolen, algo_type algos[]) { + + int i; + + for (i = 0; algos[i].name != NULL; i++) { + if (strlen(algos[i].name) == algolen + && (strncmp(algos[i].name, algo, algolen) == 0)) { + return DROPBEAR_SUCCESS; + } + } + + return DROPBEAR_FAILURE; +} + + + +/* Output a comma separated list of algorithms to a buffer */ +void buf_put_algolist(buffer * buf, algo_type localalgos[]) { + + unsigned int i, len; + unsigned int donefirst = 0; + buffer *algolist = NULL; + + algolist = buf_new(100); + for (i = 0; localalgos[i].name != NULL; i++) { + if (localalgos[i].usable) { + if (donefirst) + buf_putbyte(algolist, ','); + donefirst = 1; + len = strlen(localalgos[i].name); + buf_putbytes(algolist, localalgos[i].name, len); + } + } + buf_putstring(buf, algolist->data, algolist->len); + buf_free(algolist); +} |