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comparison common-kex.c @ 679:03073a27abb3 sha2

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- Add hmac-sha2-256 and hmac-sha2-512. Needs debugging, seems to be getting keyed incorrectly
author Matt Johnston <matt@ucc.asn.au>
date Thu, 10 May 2012 08:38:37 +0800
parents 4222a1039b06
children a4b7627b3157
comparison
equal deleted inserted replaced
678:6e0899b56ac4 679:03073a27abb3
246 246
247 /* Helper function for gen_new_keys, creates a hash. It makes a copy of the 247 /* Helper function for gen_new_keys, creates a hash. It makes a copy of the
248 * already initialised hash_state hs, which should already have processed 248 * already initialised hash_state hs, which should already have processed
249 * the dh_K and hash, since these are common. X is the letter 'A', 'B' etc. 249 * the dh_K and hash, since these are common. X is the letter 'A', 'B' etc.
250 * out must have at least min(SHA1_HASH_SIZE, outlen) bytes allocated. 250 * out must have at least min(SHA1_HASH_SIZE, outlen) bytes allocated.
251 * The output will only be expanded once, as we are assured that
252 * outlen <= 2*SHA1_HASH_SIZE for all known hashes.
253 * 251 *
254 * See Section 7.2 of rfc4253 (ssh transport) for details */ 252 * See Section 7.2 of rfc4253 (ssh transport) for details */
255 static void hashkeys(unsigned char *out, int outlen, 253 static void hashkeys(unsigned char *out, int outlen,
256 const hash_state * hs, const unsigned char X) { 254 const hash_state * hs, const unsigned char X) {
257 255
258 hash_state hs2; 256 hash_state hs2;
259 unsigned char k2[SHA1_HASH_SIZE]; /* used to extending */ 257 int offset;
260 258
261 memcpy(&hs2, hs, sizeof(hash_state)); 259 memcpy(&hs2, hs, sizeof(hash_state));
262 sha1_process(&hs2, &X, 1); 260 sha1_process(&hs2, &X, 1);
263 sha1_process(&hs2, ses.session_id, SHA1_HASH_SIZE); 261 sha1_process(&hs2, ses.session_id, SHA1_HASH_SIZE);
264 sha1_done(&hs2, out); 262 sha1_done(&hs2, out);
265 if (SHA1_HASH_SIZE < outlen) { 263 for (offset = SHA1_HASH_SIZE;
264 offset < outlen;
265 offset += SHA1_HASH_SIZE)
266 {
266 /* need to extend */ 267 /* need to extend */
268 unsigned char k2[SHA1_HASH_SIZE];
267 memcpy(&hs2, hs, sizeof(hash_state)); 269 memcpy(&hs2, hs, sizeof(hash_state));
268 sha1_process(&hs2, out, SHA1_HASH_SIZE); 270 sha1_process(&hs2, out, offset);
269 sha1_done(&hs2, k2); 271 sha1_done(&hs2, k2);
270 memcpy(&out[SHA1_HASH_SIZE], k2, outlen - SHA1_HASH_SIZE); 272 memcpy(&out[offset], k2, MIN(outlen - offset, SHA1_HASH_SIZE));
271 } 273 }
272 } 274 }
273 275
274 /* Generate the actual encryption/integrity keys, using the results of the 276 /* Generate the actual encryption/integrity keys, using the results of the
275 * key exchange, as specified in section 7.2 of the transport rfc 4253. 277 * key exchange, as specified in section 7.2 of the transport rfc 4253.