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author	Damien Miller <djm@cvs.openbsd.org>	2015-02-20 22:17:22 +0000
committer	Damien Miller <djm@cvs.openbsd.org>	2015-02-20 22:17:22 +0000
commit	c9ba317251bb1d7b46346ee3ac41354b6bfa7ef6 (patch)
tree	d73cd8330f5f3d2739351fc423fd5e48d513b11b /usr.bin
parent	baa9ac356954692ecc751959de48f726abfdc38b (diff)

UpdateHostKeys fixes:

I accidentally changed the format of the hostkeys@openssh.com messages last week without changing the extension name, and this has been causing connection failures for people who are running -current. First reported by sthen@ s/hostkeys@openssh.com/hostkeys-00@openssh.com/ Change the name of the proof message too, and reorder it a little. Also, UpdateHostKeys=ask is incompatible with ControlPersist (no TTY available to read the response) so disable UpdateHostKeys if it is in ask mode and ControlPersist is active (and document this)

Diffstat (limited to 'usr.bin')

-rw-r--r--

usr.bin/ssh/PROTOCOL

-rw-r--r--

usr.bin/ssh/clientloop.c

-rw-r--r--

usr.bin/ssh/monitor.c

-rw-r--r--

usr.bin/ssh/serverloop.c

-rw-r--r--

usr.bin/ssh/ssh.c

-rw-r--r--

usr.bin/ssh/ssh_config.5

-rw-r--r--

usr.bin/ssh/sshd.c

7 files changed, 42 insertions, 30 deletions

diff --git a/usr.bin/ssh/PROTOCOL b/usr.bin/ssh/PROTOCOL
index f9560839ec4..91bfe270d93 100644
--- a/usr.bin/ssh/PROTOCOL
+++ b/usr.bin/ssh/PROTOCOL

@@ -282,15 +282,15 @@ by the client cancel the forwarding of a Unix domain socket.

boolean FALSE

string socket path

-2.5. connection: hostkey update and rotation "hostkeys@openssh.com"

-and "hostkeys-prove@openssh.com"

+2.5. connection: hostkey update and rotation "hostkeys-00@openssh.com"

+and "hostkeys-prove-00@openssh.com"

OpenSSH supports a protocol extension allowing a server to inform

a client of all its protocol v.2 host keys after user-authentication

has completed.

byte SSH_MSG_GLOBAL_REQUEST

- string "hostkeys@openssh.com"

+ string "hostkeys-00@openssh.com"

string[] hostkeys

Upon receiving this message, a client should check which of the

@@ -300,15 +300,15 @@ to request the server prove ownership of the private half of the

key.

byte SSH_MSG_GLOBAL_REQUEST

- string "hostkeys-prove@openssh.com"

+ string "hostkeys-prove-00@openssh.com"

char 1 /* want-reply */

string[] hostkeys

When a server receives this message, it should generate a signature

using each requested key over the following:

+ string "hostkeys-prove-00@openssh.com"

string session identifier

- string "hostkeys-prove@openssh.com"

string hostkey

These signatures should be included in the reply, in the order matching

@@ -453,4 +453,4 @@ respond with a SSH_FXP_STATUS message.

This extension is advertised in the SSH_FXP_VERSION hello with version

"1".

-$OpenBSD: PROTOCOL,v 1.26 2015/02/16 22:13:32 djm Exp $

+$OpenBSD: PROTOCOL,v 1.27 2015/02/20 22:17:21 djm Exp $

diff --git a/usr.bin/ssh/clientloop.c b/usr.bin/ssh/clientloop.c
index ef0ecadd5d0..644a1f2537f 100644
--- a/usr.bin/ssh/clientloop.c
+++ b/usr.bin/ssh/clientloop.c

@@ -1,4 +1,4 @@

-/* $OpenBSD: clientloop.c,v 1.269 2015/02/16 22:13:32 djm Exp $ */

+/* $OpenBSD: clientloop.c,v 1.270 2015/02/20 22:17:21 djm Exp $ */

* Author: Tatu Ylonen <ylo@cs.hut.fi>

@@ -2247,10 +2247,10 @@ client_global_hostkeys_private_confirm(int type, u_int32_t seq, void *_ctx)

continue;

/* Prepare data to be signed: session ID, unique string, key */

sshbuf_reset(signdata);

- if ((r = sshbuf_put_string(signdata, ssh->kex->session_id,

+ if ( (r = sshbuf_put_cstring(signdata,

+ "hostkeys-prove-00@openssh.com")) != 0 ||

+ (r = sshbuf_put_string(signdata, ssh->kex->session_id,

ssh->kex->session_id_len)) != 0 ||

- (r = sshbuf_put_cstring(signdata,

- "hostkeys-prove@openssh.com")) != 0 ||

(r = sshkey_puts(ctx->keys[i], signdata)) != 0)

fatal("%s: failed to prepare signature: %s",

__func__, ssh_err(r));

@@ -2282,7 +2282,7 @@ client_global_hostkeys_private_confirm(int type, u_int32_t seq, void *_ctx)

}

- * Handle hostkeys@openssh.com global request to inform the client of all

+ * Handle hostkeys-00@openssh.com global request to inform the client of all

* the server's hostkeys. The keys are checked against the user's

* HostkeyAlgorithms preference before they are accepted.

@@ -2317,8 +2317,10 @@ client_input_hostkeys(void)

__func__, ssh_err(r));

goto out;

}

- if ((r = sshkey_from_blob(blob, len, &key)) != 0)

- fatal("%s: parse key: %s", __func__, ssh_err(r));

+ if ((r = sshkey_from_blob(blob, len, &key)) != 0) {

+ error("%s: parse key: %s", __func__, ssh_err(r));

+ goto out;

+ }

fp = sshkey_fingerprint(key, options.fingerprint_hash,

SSH_FP_DEFAULT);

debug3("%s: received %s key %s", __func__,

@@ -2358,9 +2360,10 @@ client_input_hostkeys(void)

}

if (ctx->nkeys == 0) {

- error("%s: server sent no hostkeys", __func__);

+ debug("%s: server sent no hostkeys", __func__);

goto out;

}

if ((ctx->keys_seen = calloc(ctx->nkeys,

sizeof(*ctx->keys_seen))) == NULL)

fatal("%s: calloc failed", __func__);

@@ -2400,7 +2403,7 @@ client_input_hostkeys(void)

__func__, ctx->nnew);

if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||

(r = sshpkt_put_cstring(ssh,

- "hostkeys-prove@openssh.com")) != 0 ||

+ "hostkeys-prove-00@openssh.com")) != 0 ||

(r = sshpkt_put_u8(ssh, 1)) != 0) /* bool: want reply */

fatal("%s: cannot prepare packet: %s",

__func__, ssh_err(r));

@@ -2447,7 +2450,7 @@ client_input_global_request(int type, u_int32_t seq, void *ctxt)

want_reply = packet_get_char();

debug("client_input_global_request: rtype %s want_reply %d",

rtype, want_reply);

- if (strcmp(rtype, "hostkeys@openssh.com") == 0)

+ if (strcmp(rtype, "hostkeys-00@openssh.com") == 0)

success = client_input_hostkeys();

if (want_reply) {

packet_start(success ?

diff --git a/usr.bin/ssh/monitor.c b/usr.bin/ssh/monitor.c
index 13b75a62e48..e459ef90841 100644
--- a/usr.bin/ssh/monitor.c
+++ b/usr.bin/ssh/monitor.c

@@ -1,4 +1,4 @@

-/* $OpenBSD: monitor.c,v 1.144 2015/02/16 22:13:32 djm Exp $ */

+/* $OpenBSD: monitor.c,v 1.145 2015/02/20 22:17:21 djm Exp $ */

@@ -599,7 +599,7 @@ mm_answer_sign(int sock, Buffer *m)

u_char *signature;

size_t datlen, siglen;

int r, keyid, is_proof = 0;

- const char proof_req[] = "hostkeys-prove@openssh.com";

+ const char proof_req[] = "hostkeys-prove-00@openssh.com";

debug3("%s", __func__);

@@ -629,9 +629,9 @@ mm_answer_sign(int sock, Buffer *m)

fatal("%s: no hostkey for index %d", __func__, keyid);

if ((sigbuf = sshbuf_new()) == NULL)

fatal("%s: sshbuf_new", __func__);

- if ((r = sshbuf_put_string(sigbuf, session_id2,

+ if ((r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 ||

+ (r = sshbuf_put_string(sigbuf, session_id2,

session_id2_len) != 0) ||

- (r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 ||

(r = sshkey_puts(key, sigbuf)) != 0)

fatal("%s: couldn't prepare private key "

"proof buffer: %s", __func__, ssh_err(r));

diff --git a/usr.bin/ssh/serverloop.c b/usr.bin/ssh/serverloop.c
index 6b09fbde2f5..e2f60bc6255 100644
--- a/usr.bin/ssh/serverloop.c
+++ b/usr.bin/ssh/serverloop.c

@@ -1,4 +1,4 @@

-/* $OpenBSD: serverloop.c,v 1.177 2015/02/16 22:13:32 djm Exp $ */

+/* $OpenBSD: serverloop.c,v 1.178 2015/02/20 22:17:21 djm Exp $ */

* Author: Tatu Ylonen <ylo@cs.hut.fi>

@@ -1158,10 +1158,10 @@ server_input_hostkeys_prove(struct sshbuf **respp)

sshbuf_reset(sigbuf);

free(sig);

sig = NULL;

- if ((r = sshbuf_put_string(sigbuf,

+ if ((r = sshbuf_put_cstring(sigbuf,

+ "hostkeys-prove-00@openssh.com")) != 0 ||

+ (r = sshbuf_put_string(sigbuf,

ssh->kex->session_id, ssh->kex->session_id_len)) != 0 ||

- (r = sshbuf_put_cstring(sigbuf,

- "hostkeys-prove@openssh.com")) != 0 ||

(r = sshkey_puts(key, sigbuf)) != 0 ||

(r = ssh->kex->sign(key_prv, key_pub, &sig, &slen,

sshbuf_ptr(sigbuf), sshbuf_len(sigbuf), 0)) != 0 ||

@@ -1270,7 +1270,7 @@ server_input_global_request(int type, u_int32_t seq, void *ctxt)

} else if (strcmp(rtype, "no-more-sessions@openssh.com") == 0) {

no_more_sessions = 1;

success = 1;

- } else if (strcmp(rtype, "hostkeys-prove@openssh.com") == 0) {

+ } else if (strcmp(rtype, "hostkeys-prove-00@openssh.com") == 0) {

success = server_input_hostkeys_prove(&resp);

}

if (want_reply) {

diff --git a/usr.bin/ssh/ssh.c b/usr.bin/ssh/ssh.c
index 108efd4bfa7..536f104d1a8 100644
--- a/usr.bin/ssh/ssh.c
+++ b/usr.bin/ssh/ssh.c

@@ -1,4 +1,4 @@

-/* $OpenBSD: ssh.c,v 1.414 2015/01/20 23:14:00 deraadt Exp $ */

+/* $OpenBSD: ssh.c,v 1.415 2015/02/20 22:17:21 djm Exp $ */

* Author: Tatu Ylonen <ylo@cs.hut.fi>

@@ -1042,6 +1042,12 @@ main(int ac, char **av)

strcmp(options.proxy_command, "-") == 0 &&

options.proxy_use_fdpass)

fatal("ProxyCommand=- and ProxyUseFDPass are incompatible");

+ if (options.control_persist &&

+ options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {

+ debug("UpdateHostKeys=ask is incompatible with ControlPersist; "

+ "disabling");

+ options.update_hostkeys = 0;

+ }

if (original_effective_uid != 0)

options.use_privileged_port = 0;

diff --git a/usr.bin/ssh/ssh_config.5 b/usr.bin/ssh/ssh_config.5
index fa59c518e87..140d0ba9815 100644
--- a/usr.bin/ssh/ssh_config.5
+++ b/usr.bin/ssh/ssh_config.5

@@ -33,8 +33,8 @@

.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

.\"

-.\" $OpenBSD: ssh_config.5,v 1.204 2015/02/16 22:13:32 djm Exp $

-.Dd $Mdocdate: February 16 2015 $

+.\" $OpenBSD: ssh_config.5,v 1.205 2015/02/20 22:17:21 djm Exp $

+.Dd $Mdocdate: February 20 2015 $

.Dt SSH_CONFIG 5

.Os

.Sh NAME

@@ -1524,6 +1524,9 @@ If

is set to

.Dq ask ,

then the user is asked to confirm the modifications to the known_hosts file.

+Confirmation is currently incompatible with

+.Cm ControlPersist ,

+and will be disabled if it is enabled.

.Pp

Presently, only

.Xr sshd 8

diff --git a/usr.bin/ssh/sshd.c b/usr.bin/ssh/sshd.c
index 73621167d38..a7a183a6e93 100644
--- a/usr.bin/ssh/sshd.c
+++ b/usr.bin/ssh/sshd.c

@@ -1,4 +1,4 @@

-/* $OpenBSD: sshd.c,v 1.443 2015/02/16 22:30:03 djm Exp $ */

+/* $OpenBSD: sshd.c,v 1.444 2015/02/20 22:17:21 djm Exp $ */

* Author: Tatu Ylonen <ylo@cs.hut.fi>

@@ -905,7 +905,7 @@ notify_hostkeys(struct ssh *ssh)

free(fp);

if (nkeys == 0) {

packet_start(SSH2_MSG_GLOBAL_REQUEST);

- packet_put_cstring("hostkeys@openssh.com");

+ packet_put_cstring("hostkeys-00@openssh.com");

packet_put_char(0); /* want-reply */

}

sshbuf_reset(buf);