1 files changed, 75 insertions, 8 deletions

diff --git a/sshd.c b/sshd.c
index 1306a62a7..174cc7a42 100644
--- a/sshd.c
+++ b/sshd.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshd.c,v 1.403 2013/06/05 02:27:50 dtucker Exp $ */
+/* $OpenBSD: sshd.c,v 1.404 2013/07/19 07:37:48 markus Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -106,6 +106,7 @@
 #include "canohost.h"
 #include "hostfile.h"
 #include "auth.h"
+#include "authfd.h"
 #include "misc.h"
 #include "msg.h"
 #include "dispatch.h"
@@ -194,6 +195,10 @@ char *server_version_string = NULL;
 /* for rekeying XXX fixme */
 Kex *xxx_kex;
 
+/* Daemon's agent connection */
+AuthenticationConnection *auth_conn = NULL;
+int have_agent = 0;
+
 /*
  * Any really sensitive data in the application is contained in this
  * structure. The idea is that this structure could be locked into memory so
@@ -206,6 +211,7 @@ struct {
         Key     *server_key;            /* ephemeral server key */
         Key     *ssh1_host_key;         /* ssh1 host key */
         Key     **host_keys;            /* all private host keys */
+        Key     **host_pubkeys;         /* all public host keys */
         Key     **host_certificates;    /* all public host certificates */
         int     have_ssh1_key;
         int     have_ssh2_key;
@@ -653,6 +659,8 @@ privsep_preauth(Authctxt *authctxt)
                 debug2("Network child is on pid %ld", (long)pid);
 
                 pmonitor->m_pid = pid;
+                if (have_agent)
+                        auth_conn = ssh_get_authentication_connection();
                 if (box != NULL)
                         ssh_sandbox_parent_preauth(box, pid);
                 monitor_child_preauth(authctxt, pmonitor);
@@ -767,6 +775,8 @@ list_hostkey_types(void)
         for (i = 0; i < options.num_host_key_files; i++) {
                 key = sensitive_data.host_keys[i];
                 if (key == NULL)
+                        key = sensitive_data.host_pubkeys[i];
+                if (key == NULL)
                         continue;
                 switch (key->type) {
                 case KEY_RSA:
@@ -819,6 +829,8 @@ get_hostkey_by_type(int type, int need_private)
                         break;
                 default:
                         key = sensitive_data.host_keys[i];
+                        if (key == NULL && !need_private)
+                                key = sensitive_data.host_pubkeys[i];
                         break;
                 }
                 if (key != NULL && key->type == type)
@@ -848,6 +860,14 @@ get_hostkey_by_index(int ind)
         return (sensitive_data.host_keys[ind]);
 }
 
+Key *
+get_hostkey_public_by_index(int ind)
+{
+        if (ind < 0 || ind >= options.num_host_key_files)
+                return (NULL);
+        return (sensitive_data.host_pubkeys[ind]);
+}
+
 int
 get_hostkey_index(Key *key)
 {
@@ -860,6 +880,8 @@ get_hostkey_index(Key *key)
                 } else {
                         if (key == sensitive_data.host_keys[i])
                                 return (i);
+                        if (key == sensitive_data.host_pubkeys[i])
+                                return (i);
                 }
         }
         return (-1);
@@ -1344,6 +1366,8 @@ main(int ac, char **av)
         u_int64_t ibytes, obytes;
         mode_t new_umask;
         Key *key;
+        Key *pubkey;
+        int keytype;
         Authctxt *authctxt;
         struct connection_info *connection_info = get_connection_info(0, 0);
 
@@ -1623,22 +1647,45 @@ main(int ac, char **av)
         }
         endpwent();
 
-        /* load private host keys */
+        /* load host keys */
         sensitive_data.host_keys = xcalloc(options.num_host_key_files,
             sizeof(Key *));
-        for (i = 0; i < options.num_host_key_files; i++)
+        sensitive_data.host_pubkeys = xcalloc(options.num_host_key_files,
+            sizeof(Key *));
+        for (i = 0; i < options.num_host_key_files; i++) {
                 sensitive_data.host_keys[i] = NULL;
+                sensitive_data.host_pubkeys[i] = NULL;
+        }
+
+        if (options.host_key_agent) {
+                if (strcmp(options.host_key_agent, SSH_AUTHSOCKET_ENV_NAME))
+                        setenv(SSH_AUTHSOCKET_ENV_NAME,
+                            options.host_key_agent, 1);
+                have_agent = ssh_agent_present();
+        }
 
         for (i = 0; i < options.num_host_key_files; i++) {
                 key = key_load_private(options.host_key_files[i], "", NULL);
+                pubkey = key_load_public(options.host_key_files[i], NULL);
                 sensitive_data.host_keys[i] = key;
-                if (key == NULL) {
+                sensitive_data.host_pubkeys[i] = pubkey;
+
+                if (key == NULL && pubkey != NULL && pubkey->type != KEY_RSA1 &&
+                    have_agent) {
+                        debug("will rely on agent for hostkey %s",
+                            options.host_key_files[i]);
+                        keytype = pubkey->type;
+                } else if (key != NULL) {
+                        keytype = key->type;
+                } else {
                         error("Could not load host key: %s",
                             options.host_key_files[i]);
                         sensitive_data.host_keys[i] = NULL;
+                        sensitive_data.host_pubkeys[i] = NULL;
                         continue;
                 }
-                switch (key->type) {
+
+                switch (keytype) {
                 case KEY_RSA1:
                         sensitive_data.ssh1_host_key = key;
                         sensitive_data.have_ssh1_key = 1;
@@ -1649,8 +1696,8 @@ main(int ac, char **av)
                         sensitive_data.have_ssh2_key = 1;
                         break;
                 }
-                debug("private host key: #%d type %d %s", i, key->type,
-                    key_type(key));
+                debug("private host key: #%d type %d %s", i, keytype,
+                    key_type(key ? key : pubkey));
         }
         if ((options.protocol & SSH_PROTO_1) && !sensitive_data.have_ssh1_key) {
                 logit("Disabling protocol version 1. Could not load host key");
@@ -2020,9 +2067,11 @@ main(int ac, char **av)
         buffer_init(&loginmsg);
         auth_debug_reset();
 
-        if (use_privsep)
+        if (use_privsep) {
                 if (privsep_preauth(authctxt) == 1)
                         goto authenticated;
+        } else if (compat20 && have_agent)
+                auth_conn = ssh_get_authentication_connection();
 
         /* perform the key exchange */
         /* authenticate user and start session */
@@ -2336,6 +2385,23 @@ do_ssh1_kex(void)
         packet_write_wait();
 }
 
+void
+sshd_hostkey_sign(Key *privkey, Key *pubkey, u_char **signature, u_int *slen,
+    u_char *data, u_int dlen)
+{
+        if (privkey) {
+                if (PRIVSEP(key_sign(privkey, signature, slen, data, dlen) < 0))
+                        fatal("%s: key_sign failed", __func__);
+        } else if (use_privsep) {
+                if (mm_key_sign(pubkey, signature, slen, data, dlen) < 0)
+                        fatal("%s: pubkey_sign failed", __func__);
+        } else {
+                if (ssh_agent_sign(auth_conn, pubkey, signature, slen, data,
+                    dlen))
+                        fatal("%s: ssh_agent_sign failed", __func__);
+        }
+}
+
 /*
  * SSH2 key exchange: diffie-hellman-group1-sha1
  */
@@ -2386,6 +2452,7 @@ do_ssh2_kex(void)
         kex->load_host_public_key=&get_hostkey_public_by_type;
         kex->load_host_private_key=&get_hostkey_private_by_type;
         kex->host_key_index=&get_hostkey_index;
+        kex->sign = sshd_hostkey_sign;
 
         xxx_kex = kex;