save the derived session id in kex_derive_keys() rather than making each

kex method implementation do it.

from markus@ ok djm@

9 files changed, 17 insertions, 97 deletions

diff --git a/usr.bin/ssh/kex.c b/usr.bin/ssh/kex.c
index 806aa2b6d0e..387ded02147 100644
--- a/usr.bin/ssh/kex.c
+++ b/usr.bin/ssh/kex.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.c,v 1.143 2018/12/27 03:25:25 djm Exp $ */
+/* $OpenBSD: kex.c,v 1.144 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
  *
@@ -996,6 +996,14 @@ kex_derive_keys(struct ssh *ssh, u_char *hash, u_int hashlen,
 	u_int i, j, mode, ctos;
 	int r;
 
+	/* save initial hash as session id */
+	if (kex->session_id == NULL) {
+		kex->session_id_len = hashlen;
+		kex->session_id = malloc(kex->session_id_len);
+		if (kex->session_id == NULL)
+			return SSH_ERR_ALLOC_FAIL;
+		memcpy(kex->session_id, hash, kex->session_id_len);
+	}
 	for (i = 0; i < NKEYS; i++) {
 		if ((r = derive_key(ssh, 'A'+i, kex->we_need, hash, hashlen,
 		    shared_secret, &keys[i])) != 0) {
diff --git a/usr.bin/ssh/kexc25519c.c b/usr.bin/ssh/kexc25519c.c
index e007c6a0212..23b029fac76 100644
--- a/usr.bin/ssh/kexc25519c.c
+++ b/usr.bin/ssh/kexc25519c.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexc25519c.c,v 1.10 2018/12/27 03:25:25 djm Exp $ */
+/* $OpenBSD: kexc25519c.c,v 1.11 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -142,17 +142,6 @@ input_kex_c25519_reply(int type, u_int32_t seq, struct ssh *ssh)
 	    kex->hostkey_alg, ssh->compat)) != 0)
 		goto out;
 
-	/* save session id */
-	if (kex->session_id == NULL) {
-		kex->session_id_len = hashlen;
-		kex->session_id = malloc(kex->session_id_len);
-		if (kex->session_id == NULL) {
-			r = SSH_ERR_ALLOC_FAIL;
-			goto out;
-		}
-		memcpy(kex->session_id, hash, kex->session_id_len);
-	}
-
 	if ((r = kex_derive_keys(ssh, hash, hashlen, shared_secret)) == 0)
 		r = kex_send_newkeys(ssh);
 out:
diff --git a/usr.bin/ssh/kexc25519s.c b/usr.bin/ssh/kexc25519s.c
index fc4f51d6503..7d537fb711d 100644
--- a/usr.bin/ssh/kexc25519s.c
+++ b/usr.bin/ssh/kexc25519s.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexc25519s.c,v 1.13 2019/01/19 21:43:56 djm Exp $ */
+/* $OpenBSD: kexc25519s.c,v 1.14 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -119,17 +119,6 @@ input_kex_c25519_init(int type, u_int32_t seq, struct ssh *ssh)
 	    hash, &hashlen)) < 0)
 		goto out;
 
-	/* save session id := H */
-	if (kex->session_id == NULL) {
-		kex->session_id_len = hashlen;
-		kex->session_id = malloc(kex->session_id_len);
-		if (kex->session_id == NULL) {
-			r = SSH_ERR_ALLOC_FAIL;
-			goto out;
-		}
-		memcpy(kex->session_id, hash, kex->session_id_len);
-	}
-
 	/* sign H */
 	if ((r = kex->sign(ssh, server_host_private, server_host_public,
 	    &signature, &slen, hash, hashlen, kex->hostkey_alg)) < 0)
diff --git a/usr.bin/ssh/kexdhc.c b/usr.bin/ssh/kexdhc.c
index 6e2e41def25..d2989cb3fc6 100644
--- a/usr.bin/ssh/kexdhc.c
+++ b/usr.bin/ssh/kexdhc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexdhc.c,v 1.25 2019/01/21 09:54:11 djm Exp $ */
+/* $OpenBSD: kexdhc.c,v 1.26 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -181,17 +181,6 @@ input_kex_dh(int type, u_int32_t seq, struct ssh *ssh)
 	    kex->hostkey_alg, ssh->compat)) != 0)
 		goto out;
 
-	/* save session id */
-	if (kex->session_id == NULL) {
-		kex->session_id_len = hashlen;
-		kex->session_id = malloc(kex->session_id_len);
-		if (kex->session_id == NULL) {
-			r = SSH_ERR_ALLOC_FAIL;
-			goto out;
-		}
-		memcpy(kex->session_id, hash, kex->session_id_len);
-	}
-
 	if ((r = kex_derive_keys_bn(ssh, hash, hashlen, shared_secret)) == 0)
 		r = kex_send_newkeys(ssh);
  out:
diff --git a/usr.bin/ssh/kexdhs.c b/usr.bin/ssh/kexdhs.c
index a5d6508b358..dd8aa19d41c 100644
--- a/usr.bin/ssh/kexdhs.c
+++ b/usr.bin/ssh/kexdhs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexdhs.c,v 1.31 2019/01/21 09:54:11 djm Exp $ */
+/* $OpenBSD: kexdhs.c,v 1.32 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -166,17 +166,6 @@ input_kex_dh_init(int type, u_int32_t seq, struct ssh *ssh)
 	    hash, &hashlen)) != 0)
 		goto out;
 
-	/* save session id := H */
-	if (kex->session_id == NULL) {
-		kex->session_id_len = hashlen;
-		kex->session_id = malloc(kex->session_id_len);
-		if (kex->session_id == NULL) {
-			r = SSH_ERR_ALLOC_FAIL;
-			goto out;
-		}
-		memcpy(kex->session_id, hash, kex->session_id_len);
-	}
-
 	/* sign H */
 	if ((r = kex->sign(ssh, server_host_private, server_host_public,
 	    &signature, &slen, hash, hashlen, kex->hostkey_alg)) < 0)
diff --git a/usr.bin/ssh/kexecdhc.c b/usr.bin/ssh/kexecdhc.c
index fac70b458a8..af1d4b23160 100644
--- a/usr.bin/ssh/kexecdhc.c
+++ b/usr.bin/ssh/kexecdhc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexecdhc.c,v 1.14 2018/12/27 03:25:25 djm Exp $ */
+/* $OpenBSD: kexecdhc.c,v 1.15 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -186,17 +186,6 @@ input_kex_ecdh_reply(int type, u_int32_t seq, struct ssh *ssh)
 	    hashlen, kex->hostkey_alg, ssh->compat)) != 0)
 		goto out;
 
-	/* save session id */
-	if (kex->session_id == NULL) {
-		kex->session_id_len = hashlen;
-		kex->session_id = malloc(kex->session_id_len);
-		if (kex->session_id == NULL) {
-			r = SSH_ERR_ALLOC_FAIL;
-			goto out;
-		}
-		memcpy(kex->session_id, hash, kex->session_id_len);
-	}
-
 	if ((r = kex_derive_keys_bn(ssh, hash, hashlen, shared_secret)) == 0)
 		r = kex_send_newkeys(ssh);
  out:
diff --git a/usr.bin/ssh/kexecdhs.c b/usr.bin/ssh/kexecdhs.c
index 46883229d49..70528bda60d 100644
--- a/usr.bin/ssh/kexecdhs.c
+++ b/usr.bin/ssh/kexecdhs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexecdhs.c,v 1.19 2019/01/19 21:43:56 djm Exp $ */
+/* $OpenBSD: kexecdhs.c,v 1.20 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2010 Damien Miller.  All rights reserved.
@@ -152,17 +152,6 @@ input_kex_ecdh_init(int type, u_int32_t seq, struct ssh *ssh)
 	    hash, &hashlen)) != 0)
 		goto out;
 
-	/* save session id := H */
-	if (kex->session_id == NULL) {
-		kex->session_id_len = hashlen;
-		kex->session_id = malloc(kex->session_id_len);
-		if (kex->session_id == NULL) {
-			r = SSH_ERR_ALLOC_FAIL;
-			goto out;
-		}
-		memcpy(kex->session_id, hash, kex->session_id_len);
-	}
-
 	/* sign H */
 	if ((r = kex->sign(ssh, server_host_private, server_host_public,
 	    &signature, &slen, hash, hashlen, kex->hostkey_alg)) < 0)
diff --git a/usr.bin/ssh/kexgexc.c b/usr.bin/ssh/kexgexc.c
index ea0eac944b1..6a24cf184a1 100644
--- a/usr.bin/ssh/kexgexc.c
+++ b/usr.bin/ssh/kexgexc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgexc.c,v 1.30 2019/01/21 09:54:11 djm Exp $ */
+/* $OpenBSD: kexgexc.c,v 1.31 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -222,17 +222,6 @@ input_kex_dh_gex_reply(int type, u_int32_t seq, struct ssh *ssh)
 	    hashlen, kex->hostkey_alg, ssh->compat)) != 0)
 		goto out;
 
-	/* save session id */
-	if (kex->session_id == NULL) {
-		kex->session_id_len = hashlen;
-		kex->session_id = malloc(kex->session_id_len);
-		if (kex->session_id == NULL) {
-			r = SSH_ERR_ALLOC_FAIL;
-			goto out;
-		}
-		memcpy(kex->session_id, hash, kex->session_id_len);
-	}
-
 	if ((r = kex_derive_keys_bn(ssh, hash, hashlen, shared_secret)) == 0)
 		r = kex_send_newkeys(ssh);
  out:
diff --git a/usr.bin/ssh/kexgexs.c b/usr.bin/ssh/kexgexs.c
index b98b8ccf8d1..8c217e4aeb0 100644
--- a/usr.bin/ssh/kexgexs.c
+++ b/usr.bin/ssh/kexgexs.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kexgexs.c,v 1.38 2019/01/21 09:54:11 djm Exp $ */
+/* $OpenBSD: kexgexs.c,v 1.39 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2000 Niels Provos.  All rights reserved.
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
@@ -200,17 +200,6 @@ input_kex_dh_gex_init(int type, u_int32_t seq, struct ssh *ssh)
 	    hash, &hashlen)) != 0)
 		goto out;
 
-	/* save session id := H */
-	if (kex->session_id == NULL) {
-		kex->session_id_len = hashlen;
-		kex->session_id = malloc(kex->session_id_len);
-		if (kex->session_id == NULL) {
-			r = SSH_ERR_ALLOC_FAIL;
-			goto out;
-		}
-		memcpy(kex->session_id, hash, kex->session_id_len);
-	}
-
 	/* sign H */
 	if ((r = kex->sign(ssh, server_host_private, server_host_public,
 	    &signature, &slen, hash, hashlen, kex->hostkey_alg)) < 0)