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Makefile.in contains updated files required
author Matt Johnston <matt@ucc.asn.au>
date Tue, 01 Jun 2004 02:46:09 +0000
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children e3adf4cf5465
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-1:000000000000 4:fe6bca95afa7
1 /*
2 * Dropbear - a SSH2 server
3 *
4 * Copyright (c) 2002,2003 Matt Johnston
5 * All rights reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
20 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23 * SOFTWARE. */
24
25 #include "algo.h"
26 #include "dbutil.h"
27
28 /* This file (algo.c) organises the ciphers which can be used, and is used to
29 * decide which ciphers/hashes/compression/signing to use during key exchange*/
30
31 /* Mappings for ciphers, parameters are
32 {&cipher_desc, keysize, blocksize} */
33
34 #ifdef DROPBEAR_AES128_CBC
35 const struct dropbear_cipher dropbear_aes128 =
36 {&rijndael_desc, 16, 16};
37 #endif
38 #ifdef DROPBEAR_BLOWFISH_CBC
39 const struct dropbear_cipher dropbear_blowfish =
40 {&blowfish_desc, 16, 8};
41 #endif
42 #ifdef DROPBEAR_TWOFISH128_CBC
43 const struct dropbear_cipher dropbear_twofish128 =
44 {&twofish_desc, 16, 16};
45 #endif
46 #ifdef DROPBEAR_3DES_CBC
47 const struct dropbear_cipher dropbear_3des =
48 {&des3_desc, 24, 8};
49 #endif
50
51 /* used to indicate no encryption, as defined in rfc2410 */
52 const struct dropbear_cipher dropbear_nocipher =
53 {NULL, 16, 8};
54
55 /* Mapping of ssh hashes to libtomcrypt hashes, including keysize etc.
56 {&hash_desc, keysize, hashsize} */
57
58 #ifdef DROPBEAR_SHA1_HMAC
59 const struct dropbear_hash dropbear_sha1 =
60 {&sha1_desc, 20, 20};
61 #endif
62 #ifdef DROPBEAR_MD5_HMAC
63 const struct dropbear_hash dropbear_md5 =
64 {&md5_desc, 16, 16};
65 #endif
66
67 const struct dropbear_hash dropbear_nohash =
68 {NULL, 16, 0}; /* used initially */
69
70
71 /* The following map ssh names to internal values */
72
73 algo_type sshciphers[] = {
74 #ifdef DROPBEAR_AES128_CBC
75 {"aes128-cbc", 0, (void*)&dropbear_aes128, 1},
76 #endif
77 #ifdef DROPBEAR_BLOWFISH_CBC
78 {"blowfish-cbc", 0, (void*)&dropbear_blowfish, 1},
79 #endif
80 #ifdef DROPBEAR_TWOFISH128_CBC
81 {"twofish-cbc", 0, (void*)&dropbear_twofish128, 1},
82 #endif
83 #ifdef DROPBEAR_3DES_CBC
84 {"3des-cbc", 0, (void*)&dropbear_3des, 1},
85 #endif
86 {NULL, 0, NULL, 0}
87 };
88
89 algo_type sshhashes[] = {
90 #ifdef DROPBEAR_SHA1_HMAC
91 {"hmac-sha1", 0, (void*)&dropbear_sha1, 1},
92 #endif
93 #ifdef DROPBEAR_MD5_HMAC
94 {"hmac-md5", 0, (void*)&dropbear_md5, 1},
95 #endif
96 {NULL, 0, NULL, 0}
97 };
98
99 algo_type sshcompress[] = {
100 {"none", DROPBEAR_COMP_NONE, NULL, 1},
101 #ifndef DISABLE_ZLIB
102 {"zlib", DROPBEAR_COMP_ZLIB, NULL, 1},
103 #endif
104 {NULL, 0, NULL, 0}
105 };
106
107 algo_type sshhostkey[] = {
108 #ifdef DROPBEAR_RSA
109 {"ssh-rsa", DROPBEAR_SIGNKEY_RSA, NULL, 1},
110 #endif
111 #ifdef DROPBEAR_DSS
112 {"ssh-dss", DROPBEAR_SIGNKEY_DSS, NULL, 1},
113 #endif
114 {NULL, 0, NULL, 0}
115 };
116
117 algo_type sshkex[] = {
118 {"diffie-hellman-group1-sha1", DROPBEAR_KEX_DH_GROUP1, NULL, 1},
119 {NULL, 0, NULL, 0}
120 };
121
122
123 /* Register the compiled in ciphers.
124 * This should be run before using any of the ciphers/hashes */
125 void crypto_init() {
126
127 const struct _cipher_descriptor *regciphers[] = {
128 #ifdef DROPBEAR_AES128_CBC
129 &rijndael_desc,
130 #endif
131 #ifdef DROPBEAR_BLOWFISH_CBC
132 &blowfish_desc,
133 #endif
134 #ifdef DROPBEAR_TWOFISH128_CBC
135 &twofish_desc,
136 #endif
137 #ifdef DROPBEAR_3DES_CBC
138 &des3_desc,
139 #endif
140 NULL
141 };
142
143 const struct _hash_descriptor *reghashes[] = {
144 /* we need sha1 for hostkey stuff regardless */
145 &sha1_desc,
146 #ifdef DROPBEAR_MD5_HMAC
147 &md5_desc,
148 #endif
149 NULL
150 };
151 int i;
152
153 for (i = 0; regciphers[i] != NULL; i++) {
154 if (register_cipher(regciphers[i]) == -1) {
155 dropbear_exit("error registering crypto");
156 }
157 }
158
159 for (i = 0; reghashes[i] != NULL; i++) {
160 if (register_hash(reghashes[i]) == -1) {
161 dropbear_exit("error registering crypto");
162 }
163 }
164 }
165
166 /* algolen specifies the length of algo, algos is our local list to match
167 * against.
168 * Returns DROPBEAR_SUCCESS if we have a match for algo, DROPBEAR_FAILURE
169 * otherwise */
170 int have_algo(char* algo, size_t algolen, algo_type algos[]) {
171
172 int i;
173
174 for (i = 0; algos[i].name != NULL; i++) {
175 if (strlen(algos[i].name) == algolen
176 && (strncmp(algos[i].name, algo, algolen) == 0)) {
177 return DROPBEAR_SUCCESS;
178 }
179 }
180
181 return DROPBEAR_FAILURE;
182 }
183
184
185
186 /* Output a comma separated list of algorithms to a buffer */
187 void buf_put_algolist(buffer * buf, algo_type localalgos[]) {
188
189 unsigned int pos = 0, i, len;
190 char str[50]; /* enough for local algo storage */
191
192 for (i = 0; localalgos[i].name != NULL; i++) {
193 if (localalgos[i].usable) {
194 /* Avoid generating a trailing comma */
195 if (pos)
196 str[pos++] = ',';
197 len = strlen(localalgos[i].name);
198 memcpy(&str[pos], localalgos[i].name, len);
199 pos += len;
200 }
201 }
202 str[pos]=0;
203 /* Debug this */
204 TRACE(("buf_put_algolist: %s", str));
205 buf_putstring(buf, str, pos);
206 }