- djm@cvs.openbsd.org 2005/11/04 05:15:59
[kex.c kex.h kexdh.c kexdhc.c kexdhs.c kexgex.c kexgexc.c kexgexs.c]
remove hardcoded hash lengths in key exchange code, allowing
implementation of KEX methods with different hashes (e.g. SHA-256);
ok markus@ dtucker@ stevesk@
diff --git a/kexdhs.c b/kexdhs.c
index 225e655..26c8cdf 100644
--- a/kexdhs.c
+++ b/kexdhs.c
@@ -23,7 +23,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: kexdhs.c,v 1.2 2004/06/13 12:53:24 djm Exp $");
+RCSID("$OpenBSD: kexdhs.c,v 1.3 2005/11/04 05:15:59 djm Exp $");
#include "xmalloc.h"
#include "key.h"
@@ -41,7 +41,7 @@
DH *dh;
Key *server_host_key;
u_char *kbuf, *hash, *signature = NULL, *server_host_key_blob = NULL;
- u_int sbloblen, klen, kout;
+ u_int sbloblen, klen, kout, hashlen;
u_int slen;
/* generate server DH public key */
@@ -103,7 +103,7 @@
key_to_blob(server_host_key, &server_host_key_blob, &sbloblen);
/* calc H */
- hash = kex_dh_hash(
+ kex_dh_hash(
kex->client_version_string,
kex->server_version_string,
buffer_ptr(&kex->peer), buffer_len(&kex->peer),
@@ -111,21 +111,20 @@
server_host_key_blob, sbloblen,
dh_client_pub,
dh->pub_key,
- shared_secret
+ shared_secret,
+ &hash, &hashlen
);
BN_clear_free(dh_client_pub);
/* save session id := H */
- /* XXX hashlen depends on KEX */
if (kex->session_id == NULL) {
- kex->session_id_len = 20;
+ kex->session_id_len = hashlen;
kex->session_id = xmalloc(kex->session_id_len);
memcpy(kex->session_id, hash, kex->session_id_len);
}
/* sign H */
- /* XXX hashlen depends on KEX */
- PRIVSEP(key_sign(server_host_key, &signature, &slen, hash, 20));
+ PRIVSEP(key_sign(server_host_key, &signature, &slen, hash, hashlen));
/* destroy_sensitive_data(); */
@@ -141,7 +140,7 @@
/* have keys, free DH */
DH_free(dh);
- kex_derive_keys(kex, hash, shared_secret);
+ kex_derive_keys(kex, hash, hashlen, shared_secret);
BN_clear_free(shared_secret);
kex_finish(kex);
}