1 files changed, 424 insertions, 31 deletions

diff --git a/clientloop.c b/clientloop.c
index 397c96532..a9c8a90f0 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.261 2014/07/15 15:54:14 millert Exp $ */
+/* $OpenBSD: clientloop.c,v 1.272 2015/02/25 19:54:02 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -61,9 +61,9 @@
 
 #include "includes.h"
 
+#include <sys/param.h>  /* MIN MAX */
 #include <sys/types.h>
 #include <sys/ioctl.h>
-#include <sys/param.h>
 #ifdef HAVE_SYS_STAT_H
 # include <sys/stat.h>
 #endif
@@ -85,6 +85,7 @@
 #include <termios.h>
 #include <pwd.h>
 #include <unistd.h>
+#include <limits.h>
 
 #include "openbsd-compat/sys-queue.h"
 #include "xmalloc.h"
@@ -110,6 +111,8 @@
 #include "match.h"
 #include "msg.h"
 #include "roaming.h"
+#include "ssherr.h"
+#include "hostfile.h"
 
 /* import options */
 extern Options options;
@@ -191,9 +194,6 @@ TAILQ_HEAD(global_confirms, global_confirm);
 static struct global_confirms global_confirms =
     TAILQ_HEAD_INITIALIZER(global_confirms);
 
-/*XXX*/
-extern Kex *xxx_kex;
-
 void ssh_process_session2_setup(int, int, int, Buffer *);
 
 /* Restores stdin to blocking mode. */
@@ -341,12 +341,12 @@ client_x11_get_proto(const char *display, const char *xauth_path,
                         display = xdisplay;
                 }
                 if (trusted == 0) {
-                        xauthdir = xmalloc(MAXPATHLEN);
-                        xauthfile = xmalloc(MAXPATHLEN);
-                        mktemp_proto(xauthdir, MAXPATHLEN);
+                        xauthdir = xmalloc(PATH_MAX);
+                        xauthfile = xmalloc(PATH_MAX);
+                        mktemp_proto(xauthdir, PATH_MAX);
                         if (mkdtemp(xauthdir) != NULL) {
                                 do_unlink = 1;
-                                snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
+                                snprintf(xauthfile, PATH_MAX, "%s/xauthfile",
                                     xauthdir);
                                 snprintf(cmd, sizeof(cmd),
                                     "%s -f %s generate %s " SSH_X11_PROTO
@@ -538,13 +538,13 @@ client_check_window_change(void)
         }
 }
 
-static void
+static int
 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
 {
         struct global_confirm *gc;
 
         if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
-                return;
+                return 0;
         if (gc->cb != NULL)
                 gc->cb(type, seq, gc->ctx);
         if (--gc->ref_count <= 0) {
@@ -554,6 +554,7 @@ client_global_request_reply(int type, u_int32_t seq, void *ctxt)
         }
 
         packet_set_alive_timeouts(0);
+        return 0;
 }
 
 static void
@@ -1414,8 +1415,7 @@ client_process_output(fd_set *writeset)
 static void
 client_process_buffered_input_packets(void)
 {
-        dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
-            compat20 ? xxx_kex : NULL);
+        dispatch_run(DISPATCH_NONBLOCK, &quit_pending, active_state);
 }
 
 /* scan buf[] for '~' before sending data to the peer */
@@ -1469,7 +1469,7 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
 {
         fd_set *readset = NULL, *writeset = NULL;
         double start_time, total_time;
-        int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
+        int r, max_fd = 0, max_fd2 = 0, len, rekeying = 0;
         u_int64_t ibytes, obytes;
         u_int nalloc = 0;
         char buf[100];
@@ -1554,7 +1554,7 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
                 if (compat20 && session_closed && !channel_still_open())
                         break;
 
-                rekeying = (xxx_kex != NULL && !xxx_kex->done);
+                rekeying = (active_state->kex != NULL && !active_state->kex->done);
 
                 if (rekeying) {
                         debug("rekeying in progress");
@@ -1598,8 +1598,10 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
                         channel_after_select(readset, writeset);
                         if (need_rekeying || packet_need_rekeying()) {
                                 debug("need rekeying");
-                                xxx_kex->done = 0;
-                                kex_send_kexinit(xxx_kex);
+                                active_state->kex->done = 0;
+                                if ((r = kex_send_kexinit(active_state)) != 0)
+                                        fatal("%s: kex_send_kexinit: %s",
+                                            __func__, ssh_err(r));
                                 need_rekeying = 0;
                         }
                 }
@@ -1728,8 +1730,7 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
 
         /* Report bytes transferred, and transfer rates. */
         total_time = get_current_time() - start_time;
-        packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
-        packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
+        packet_get_bytes(&ibytes, &obytes);
         verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
             (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
         if (total_time > 0)
@@ -1742,7 +1743,7 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
 
 /*********/
 
-static void
+static int
 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
 {
         u_int data_len;
@@ -1751,8 +1752,9 @@ client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
         buffer_append(&stdout_buffer, data, data_len);
         explicit_bzero(data, data_len);
         free(data);
+        return 0;
 }
-static void
+static int
 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
 {
         u_int data_len;
@@ -1761,8 +1763,9 @@ client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
         buffer_append(&stderr_buffer, data, data_len);
         explicit_bzero(data, data_len);
         free(data);
+        return 0;
 }
-static void
+static int
 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
 {
         exit_status = packet_get_int();
@@ -1777,12 +1780,14 @@ client_input_exit_status(int type, u_int32_t seq, void *ctxt)
         packet_write_wait();
         /* Flag that we want to exit. */
         quit_pending = 1;
+        return 0;
 }
-static void
+
+static int
 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
 {
         Channel *c = NULL;
-        int remote_id, sock;
+        int r, remote_id, sock;
 
         /* Read the remote channel number from the message. */
         remote_id = packet_get_int();
@@ -1792,7 +1797,11 @@ client_input_agent_open(int type, u_int32_t seq, void *ctxt)
          * Get a connection to the local authentication agent (this may again
          * get forwarded).
          */
-        sock = ssh_get_authentication_socket();
+        if ((r = ssh_get_authentication_socket(&sock)) != 0 &&
+            r != SSH_ERR_AGENT_NOT_PRESENT)
+                debug("%s: ssh_get_authentication_socket: %s",
+                    __func__, ssh_err(r));
+
 
         /*
          * If we could not connect the agent, send an error message back to
@@ -1817,6 +1826,7 @@ client_input_agent_open(int type, u_int32_t seq, void *ctxt)
                 packet_put_int(c->self);
         }
         packet_send();
+        return 0;
 }
 
 static Channel *
@@ -1910,7 +1920,7 @@ static Channel *
 client_request_agent(const char *request_type, int rchan)
 {
         Channel *c = NULL;
-        int sock;
+        int r, sock;
 
         if (!options.forward_agent) {
                 error("Warning: ssh server tried agent forwarding.");
@@ -1918,9 +1928,12 @@ client_request_agent(const char *request_type, int rchan)
                     "malicious server.");
                 return NULL;
         }
-        sock = ssh_get_authentication_socket();
-        if (sock < 0)
+        if ((r = ssh_get_authentication_socket(&sock)) != 0) {
+                if (r != SSH_ERR_AGENT_NOT_PRESENT)
+                        debug("%s: ssh_get_authentication_socket: %s",
+                            __func__, ssh_err(r));
                 return NULL;
+        }
         c = channel_new("authentication agent connection",
             SSH_CHANNEL_OPEN, sock, sock, -1,
             CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
@@ -1974,7 +1987,7 @@ client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
 }
 
 /* XXXX move to generic input handler */
-static void
+static int
 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
 {
         Channel *c = NULL;
@@ -2025,8 +2038,10 @@ client_input_channel_open(int type, u_int32_t seq, void *ctxt)
                 packet_send();
         }
         free(ctype);
+        return 0;
 }
-static void
+
+static int
 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
 {
         Channel *c = NULL;
@@ -2071,18 +2086,395 @@ client_input_channel_req(int type, u_int32_t seq, void *ctxt)
                 packet_send();
         }
         free(rtype);
+        return 0;
+}
+
+struct hostkeys_update_ctx {
+        /* The hostname and (optionally) IP address string for the server */
+        char *host_str, *ip_str;
+
+        /*
+         * Keys received from the server and a flag for each indicating
+         * whether they already exist in known_hosts.
+         * keys_seen is filled in by hostkeys_find() and later (for new
+         * keys) by client_global_hostkeys_private_confirm().
+         */
+        struct sshkey **keys;
+        int *keys_seen;
+        size_t nkeys;
+
+        size_t nnew;
+
+        /*
+         * Keys that are in known_hosts, but were not present in the update
+         * from the server (i.e. scheduled to be deleted).
+         * Filled in by hostkeys_find().
+         */
+        struct sshkey **old_keys;
+        size_t nold;
+};
+
+static void
+hostkeys_update_ctx_free(struct hostkeys_update_ctx *ctx)
+{
+        size_t i;
+
+        if (ctx == NULL)
+                return;
+        for (i = 0; i < ctx->nkeys; i++)
+                sshkey_free(ctx->keys[i]);
+        free(ctx->keys);
+        free(ctx->keys_seen);
+        for (i = 0; i < ctx->nold; i++)
+                sshkey_free(ctx->old_keys[i]);
+        free(ctx->old_keys);
+        free(ctx->host_str);
+        free(ctx->ip_str);
+        free(ctx);
+}
+
+static int
+hostkeys_find(struct hostkey_foreach_line *l, void *_ctx)
+{
+        struct hostkeys_update_ctx *ctx = (struct hostkeys_update_ctx *)_ctx;
+        size_t i;
+        struct sshkey **tmp;
+
+        if (l->status != HKF_STATUS_MATCHED || l->key == NULL ||
+            l->key->type == KEY_RSA1)
+                return 0;
+
+        /* Mark off keys we've already seen for this host */
+        for (i = 0; i < ctx->nkeys; i++) {
+                if (sshkey_equal(l->key, ctx->keys[i])) {
+                        debug3("%s: found %s key at %s:%ld", __func__,
+                            sshkey_ssh_name(ctx->keys[i]), l->path, l->linenum);
+                        ctx->keys_seen[i] = 1;
+                        return 0;
+                }
+        }
+        /* This line contained a key that not offered by the server */
+        debug3("%s: deprecated %s key at %s:%ld", __func__,
+            sshkey_ssh_name(l->key), l->path, l->linenum);
+        if ((tmp = reallocarray(ctx->old_keys, ctx->nold + 1,
+            sizeof(*ctx->old_keys))) == NULL)
+                fatal("%s: reallocarray failed nold = %zu",
+                    __func__, ctx->nold);
+        ctx->old_keys = tmp;
+        ctx->old_keys[ctx->nold++] = l->key;
+        l->key = NULL;
+
+        return 0;
+}
+
+static void
+update_known_hosts(struct hostkeys_update_ctx *ctx)
+{
+        int r, was_raw = 0;
+        int loglevel = options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK ?
+            SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_VERBOSE;
+        char *fp, *response;
+        size_t i;
+
+        for (i = 0; i < ctx->nkeys; i++) {
+                if (ctx->keys_seen[i] != 2)
+                        continue;
+                if ((fp = sshkey_fingerprint(ctx->keys[i],
+                    options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
+                        fatal("%s: sshkey_fingerprint failed", __func__);
+                do_log2(loglevel, "Learned new hostkey: %s %s",
+                    sshkey_type(ctx->keys[i]), fp);
+                free(fp);
+        }
+        for (i = 0; i < ctx->nold; i++) {
+                if ((fp = sshkey_fingerprint(ctx->old_keys[i],
+                    options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
+                        fatal("%s: sshkey_fingerprint failed", __func__);
+                do_log2(loglevel, "Deprecating obsolete hostkey: %s %s",
+                    sshkey_type(ctx->old_keys[i]), fp);
+                free(fp);
+        }
+        if (options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {
+                if (get_saved_tio() != NULL) {
+                        leave_raw_mode(1);
+                        was_raw = 1;
+                }
+                response = NULL;
+                for (i = 0; !quit_pending && i < 3; i++) {
+                        free(response);
+                        response = read_passphrase("Accept updated hostkeys? "
+                            "(yes/no): ", RP_ECHO);
+                        if (strcasecmp(response, "yes") == 0)
+                                break;
+                        else if (quit_pending || response == NULL ||
+                            strcasecmp(response, "no") == 0) {
+                                options.update_hostkeys = 0;
+                                break;
+                        } else {
+                                do_log2(loglevel, "Please enter "
+                                    "\"yes\" or \"no\"");
+                        }
+                }
+                if (quit_pending || i >= 3 || response == NULL)
+                        options.update_hostkeys = 0;
+                free(response);
+                if (was_raw)
+                        enter_raw_mode(1);
+        }
+
+        /*
+         * Now that all the keys are verified, we can go ahead and replace
+         * them in known_hosts (assuming SSH_UPDATE_HOSTKEYS_ASK didn't
+         * cancel the operation).
+         */
+        if (options.update_hostkeys != 0 &&
+            (r = hostfile_replace_entries(options.user_hostfiles[0],
+            ctx->host_str, ctx->ip_str, ctx->keys, ctx->nkeys,
+            options.hash_known_hosts, 0,
+            options.fingerprint_hash)) != 0)
+                error("%s: hostfile_replace_entries failed: %s",
+                    __func__, ssh_err(r));
 }
+
 static void
+client_global_hostkeys_private_confirm(int type, u_int32_t seq, void *_ctx)
+{
+        struct ssh *ssh = active_state; /* XXX */
+        struct hostkeys_update_ctx *ctx = (struct hostkeys_update_ctx *)_ctx;
+        size_t i, ndone;
+        struct sshbuf *signdata;
+        int r;
+        const u_char *sig;
+        size_t siglen;
+
+        if (ctx->nnew == 0)
+                fatal("%s: ctx->nnew == 0", __func__); /* sanity */
+        if (type != SSH2_MSG_REQUEST_SUCCESS) {
+                error("Server failed to confirm ownership of "
+                    "private host keys");
+                hostkeys_update_ctx_free(ctx);
+                return;
+        }
+        if ((signdata = sshbuf_new()) == NULL)
+                fatal("%s: sshbuf_new failed", __func__);
+        /* Don't want to accidentally accept an unbound signature */
+        if (ssh->kex->session_id_len == 0)
+                fatal("%s: ssh->kex->session_id_len == 0", __func__);
+        /*
+         * Expect a signature for each of the ctx->nnew private keys we
+         * haven't seen before. They will be in the same order as the
+         * ctx->keys where the corresponding ctx->keys_seen[i] == 0.
+         */
+        for (ndone = i = 0; i < ctx->nkeys; i++) {
+                if (ctx->keys_seen[i])
+                        continue;
+                /* Prepare data to be signed: session ID, unique string, key */
+                sshbuf_reset(signdata);
+                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 = sshkey_puts(ctx->keys[i], signdata)) != 0)
+                        fatal("%s: failed to prepare signature: %s",
+                            __func__, ssh_err(r));
+                /* Extract and verify signature */
+                if ((r = sshpkt_get_string_direct(ssh, &sig, &siglen)) != 0) {
+                        error("%s: couldn't parse message: %s",
+                            __func__, ssh_err(r));
+                        goto out;
+                }
+                if ((r = sshkey_verify(ctx->keys[i], sig, siglen,
+                    sshbuf_ptr(signdata), sshbuf_len(signdata), 0)) != 0) {
+                        error("%s: server gave bad signature for %s key %zu",
+                            __func__, sshkey_type(ctx->keys[i]), i);
+                        goto out;
+                }
+                /* Key is good. Mark it as 'seen' */
+                ctx->keys_seen[i] = 2;
+                ndone++;
+        }
+        if (ndone != ctx->nnew)
+                fatal("%s: ndone != ctx->nnew (%zu / %zu)", __func__,
+                    ndone, ctx->nnew);  /* Shouldn't happen */
+        ssh_packet_check_eom(ssh);
+
+        /* Make the edits to known_hosts */
+        update_known_hosts(ctx);
+ out:
+        hostkeys_update_ctx_free(ctx);
+}
+
+/*
+ * 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.
+ */
+static int
+client_input_hostkeys(void)
+{
+        struct ssh *ssh = active_state; /* XXX */
+        const u_char *blob = NULL;
+        size_t i, len = 0;
+        struct sshbuf *buf = NULL;
+        struct sshkey *key = NULL, **tmp;
+        int r;
+        char *fp;
+        static int hostkeys_seen = 0; /* XXX use struct ssh */
+        extern struct sockaddr_storage hostaddr; /* XXX from ssh.c */
+        struct hostkeys_update_ctx *ctx = NULL;
+
+        if (hostkeys_seen)
+                fatal("%s: server already sent hostkeys", __func__);
+        if (options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK &&
+            options.batch_mode)
+                return 1; /* won't ask in batchmode, so don't even try */
+        if (!options.update_hostkeys || options.num_user_hostfiles <= 0)
+                return 1;
+
+        ctx = xcalloc(1, sizeof(*ctx));
+        while (ssh_packet_remaining(ssh) > 0) {
+                sshkey_free(key);
+                key = NULL;
+                if ((r = sshpkt_get_string_direct(ssh, &blob, &len)) != 0) {
+                        error("%s: couldn't parse message: %s",
+                            __func__, ssh_err(r));
+                        goto out;
+                }
+                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__,
+                    sshkey_type(key), fp);
+                free(fp);
+                /* Check that the key is accepted in HostkeyAlgorithms */
+                if (options.hostkeyalgorithms != NULL &&
+                    match_pattern_list(sshkey_ssh_name(key),
+                    options.hostkeyalgorithms,
+                    strlen(options.hostkeyalgorithms), 0) != 1) {
+                        debug3("%s: %s key not permitted by HostkeyAlgorithms",
+                            __func__, sshkey_ssh_name(key));
+                        continue;
+                }
+                /* Skip certs */
+                if (sshkey_is_cert(key)) {
+                        debug3("%s: %s key is a certificate; skipping",
+                            __func__, sshkey_ssh_name(key));
+                        continue;
+                }
+                /* Ensure keys are unique */
+                for (i = 0; i < ctx->nkeys; i++) {
+                        if (sshkey_equal(key, ctx->keys[i])) {
+                                error("%s: received duplicated %s host key",
+                                    __func__, sshkey_ssh_name(key));
+                                goto out;
+                        }
+                }
+                /* Key is good, record it */
+                if ((tmp = reallocarray(ctx->keys, ctx->nkeys + 1,
+                    sizeof(*ctx->keys))) == NULL)
+                        fatal("%s: reallocarray failed nkeys = %zu",
+                            __func__, ctx->nkeys);
+                ctx->keys = tmp;
+                ctx->keys[ctx->nkeys++] = key;
+                key = NULL;
+        }
+
+        if (ctx->nkeys == 0) {
+                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__);
+
+        get_hostfile_hostname_ipaddr(host,
+            options.check_host_ip ? (struct sockaddr *)&hostaddr : NULL,
+            options.port, &ctx->host_str,
+            options.check_host_ip ? &ctx->ip_str : NULL);
+
+        /* Find which keys we already know about. */
+        if ((r = hostkeys_foreach(options.user_hostfiles[0], hostkeys_find,
+            ctx, ctx->host_str, ctx->ip_str,
+            HKF_WANT_PARSE_KEY|HKF_WANT_MATCH)) != 0) {
+                error("%s: hostkeys_foreach failed: %s", __func__, ssh_err(r));
+                goto out;
+        }
+
+        /* Figure out if we have any new keys to add */
+        ctx->nnew = 0;
+        for (i = 0; i < ctx->nkeys; i++) {
+                if (!ctx->keys_seen[i])
+                        ctx->nnew++;
+        }
+
+        debug3("%s: %zu keys from server: %zu new, %zu retained. %zu to remove",
+            __func__, ctx->nkeys, ctx->nnew, ctx->nkeys - ctx->nnew, ctx->nold);
+
+        if (ctx->nnew == 0 && ctx->nold != 0) {
+                /* We have some keys to remove. Just do it. */
+                update_known_hosts(ctx);
+        } else if (ctx->nnew != 0) {
+                /*
+                 * We have received hitherto-unseen keys from the server.
+                 * Ask the server to confirm ownership of the private halves.
+                 */
+                debug3("%s: asking server to prove ownership for %zu keys",
+                    __func__, ctx->nnew);
+                if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
+                    (r = sshpkt_put_cstring(ssh,
+                    "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));
+                if ((buf = sshbuf_new()) == NULL)
+                        fatal("%s: sshbuf_new", __func__);
+                for (i = 0; i < ctx->nkeys; i++) {
+                        if (ctx->keys_seen[i])
+                                continue;
+                        sshbuf_reset(buf);
+                        if ((r = sshkey_putb(ctx->keys[i], buf)) != 0)
+                                fatal("%s: sshkey_putb: %s",
+                                    __func__, ssh_err(r));
+                        if ((r = sshpkt_put_stringb(ssh, buf)) != 0)
+                                fatal("%s: sshpkt_put_string: %s",
+                                    __func__, ssh_err(r));
+                }
+                if ((r = sshpkt_send(ssh)) != 0)
+                        fatal("%s: sshpkt_send: %s", __func__, ssh_err(r));
+                client_register_global_confirm(
+                    client_global_hostkeys_private_confirm, ctx);
+                ctx = NULL;  /* will be freed in callback */
+        }
+
+        /* Success */
+ out:
+        hostkeys_update_ctx_free(ctx);
+        sshkey_free(key);
+        sshbuf_free(buf);
+        /*
+         * NB. Return success for all cases. The server doesn't need to know
+         * what the client does with its hosts file.
+         */
+        return 1;
+}
+
+static int
 client_input_global_request(int type, u_int32_t seq, void *ctxt)
 {
         char *rtype;
         int want_reply;
         int success = 0;
 
-        rtype = packet_get_string(NULL);
+        rtype = packet_get_cstring(NULL);
         want_reply = packet_get_char();
         debug("client_input_global_request: rtype %s want_reply %d",
             rtype, want_reply);
+        if (strcmp(rtype, "hostkeys-00@openssh.com") == 0)
+                success = client_input_hostkeys();
         if (want_reply) {
                 packet_start(success ?
                     SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
@@ -2090,6 +2482,7 @@ client_input_global_request(int type, u_int32_t seq, void *ctxt)
                 packet_write_wait();
         }
         free(rtype);
+        return 0;
 }
 
 void