1 files changed, 63 insertions, 48 deletions

diff --git a/sshconnect2.c b/sshconnect2.c
index 1a69c6b2b..5190b07e5 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -1,3 +1,4 @@
+/* $OpenBSD: sshconnect2.c,v 1.162 2006/08/30 00:06:51 dtucker Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -23,18 +24,30 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.143 2005/10/14 02:17:59 stevesk Exp $");
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+
+#include <errno.h>
+#include <pwd.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
 
 #include "openbsd-compat/sys-queue.h"
 
+#include "xmalloc.h"
 #include "ssh.h"
 #include "ssh2.h"
-#include "xmalloc.h"
 #include "buffer.h"
 #include "packet.h"
 #include "compat.h"
-#include "bufaux.h"
 #include "cipher.h"
+#include "key.h"
 #include "kex.h"
 #include "myproposal.h"
 #include "sshconnect.h"
@@ -49,6 +62,7 @@ RCSID("$OpenBSD: sshconnect2.c,v 1.143 2005/10/14 02:17:59 stevesk Exp $");
 #include "canohost.h"
 #include "msg.h"
 #include "pathnames.h"
+#include "uidswap.h"
 
 #ifdef GSSAPI
 #include "ssh-gss.h"
@@ -85,30 +99,30 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
         Kex *kex;
 
 #ifdef GSSAPI
-        char *orig, *gss;
-        int len;
-        char *gss_host;
+        char *orig = NULL, *gss = NULL;
+        char *gss_host = NULL;
 #endif
 
         xxx_host = host;
         xxx_hostaddr = hostaddr;
 
 #ifdef GSSAPI
-        /* Add the GSSAPI mechanisms currently supported on this client to
-         * the key exchange algorithm proposal */
-        orig = myproposal[PROPOSAL_KEX_ALGS];
-        if (options.gss_trust_dns)
-                gss_host = (char *)get_canonical_hostname(1);
-        else
-                gss_host = host;
-
-        gss = ssh_gssapi_client_mechanisms(gss_host);
-        if (gss) {
-                debug("Offering GSSAPI proposal: %s", gss);
-                len = strlen(orig) + strlen(gss) + 2;
-                myproposal[PROPOSAL_KEX_ALGS] = xmalloc(len);
-                snprintf(myproposal[PROPOSAL_KEX_ALGS], len, "%s,%s", gss, 
-                    orig);
+        if (options.gss_keyex) {
+                /* Add the GSSAPI mechanisms currently supported on this 
+                 * client to the key exchange algorithm proposal */
+                orig = myproposal[PROPOSAL_KEX_ALGS];
+
+                if (options.gss_trust_dns)
+                        gss_host = (char *)get_canonical_hostname(1);
+                else
+                        gss_host = host;
+
+                gss = ssh_gssapi_client_mechanisms(gss_host);
+                if (gss) {
+                        debug("Offering GSSAPI proposal: %s", gss);
+                        xasprintf(&myproposal[PROPOSAL_KEX_ALGS],
+                            "%s,%s", gss, orig);
+                }
         }
 #endif
 
@@ -142,11 +156,9 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
 #ifdef GSSAPI
         /* If we've got GSSAPI algorithms, then we also support the
          * 'null' hostkey, as a last resort */
-        if (gss) {
+        if (options.gss_keyex && gss) {
                 orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
-                len = strlen(orig) + sizeof(",null");
-                myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = xmalloc(len);
-                snprintf(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS], len, 
+                xasprintf(&myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS], 
                     "%s,null", orig);
         }
 #endif
@@ -159,8 +171,10 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
         kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
         kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
         kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
+        kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
 #ifdef GSSAPI
         kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_client;
+        kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_client;
         kex->kex[KEX_GSS_GEX_SHA1] = kexgss_client;
 #endif
         kex->client_version_string=client_version_string;
@@ -415,7 +429,7 @@ input_userauth_banner(int type, u_int32_t seq, void *ctxt)
         debug3("input_userauth_banner");
         msg = packet_get_string(NULL);
         lang = packet_get_string(NULL);
-        if (options.log_level > SYSLOG_LEVEL_QUIET)
+        if (options.log_level >= SYSLOG_LEVEL_INFO)
                 fprintf(stderr, "%s", msg);
         xfree(msg);
         xfree(lang);
@@ -537,6 +551,12 @@ userauth_gssapi(Authctxt *authctxt)
         static u_int mech = 0;
         OM_uint32 min;
         int ok = 0;
+        char *gss_host = NULL;
+
+        if (options.gss_trust_dns)
+                gss_host = (char *)get_canonical_hostname(1);
+        else
+                gss_host = (char *)authctxt->host;
 
         /* Try one GSSAPI method at a time, rather than sending them all at
          * once. */
@@ -546,15 +566,10 @@ userauth_gssapi(Authctxt *authctxt)
 
         /* Check to see if the mechanism is usable before we offer it */
         while (mech < gss_supported->count && !ok) {
-                if (gssctxt)
-                        ssh_gssapi_delete_ctx(&gssctxt);
-                ssh_gssapi_build_ctx(&gssctxt);
-                ssh_gssapi_set_oid(gssctxt, &gss_supported->elements[mech]);
-
                 /* My DER encoding requires length<128 */
                 if (gss_supported->elements[mech].length < 128 &&
-                    !GSS_ERROR(ssh_gssapi_import_name(gssctxt,
-                    authctxt->host))) {
+                    ssh_gssapi_check_mechanism(&gssctxt, 
+                    &gss_supported->elements[mech], gss_host)) {
                         ok = 1; /* Mechanism works */
                 } else {
                         mech++;
@@ -650,8 +665,8 @@ input_gssapi_response(int type, u_int32_t plen, void *ctxt)
 {
         Authctxt *authctxt = ctxt;
         Gssctxt *gssctxt;
-        int oidlen;
-        char *oidv;
+        u_int oidlen;
+        u_char *oidv;
 
         if (authctxt == NULL)
                 fatal("input_gssapi_response: no authentication context");
@@ -1057,14 +1072,16 @@ load_identity_file(char *filename)
 {
         Key *private;
         char prompt[300], *passphrase;
-        int quit, i;
+        int perm_ok, quit, i;
         struct stat st;
 
         if (stat(filename, &st) < 0) {
                 debug3("no such identity: %s", filename);
                 return NULL;
         }
-        private = key_load_private_type(KEY_UNSPEC, filename, "", NULL);
+        private = key_load_private_type(KEY_UNSPEC, filename, "", NULL, &perm_ok);
+        if (!perm_ok)
+                return NULL;
         if (private == NULL) {
                 if (options.batch_mode)
                         return NULL;
@@ -1073,8 +1090,8 @@ load_identity_file(char *filename)
                 for (i = 0; i < options.number_of_password_prompts; i++) {
                         passphrase = read_passphrase(prompt, 0);
                         if (strcmp(passphrase, "") != 0) {
-                                private = key_load_private_type(KEY_UNSPEC, filename,
-                                    passphrase, NULL);
+                                private = key_load_private_type(KEY_UNSPEC,
+                                    filename, passphrase, NULL, NULL);
                                 quit = 0;
                         } else {
                                 debug2("no passphrase given, try next key");
@@ -1117,8 +1134,7 @@ pubkey_prepare(Authctxt *authctxt)
                 if (key && key->type == KEY_RSA1)
                         continue;
                 options.identity_keys[i] = NULL;
-                id = xmalloc(sizeof(*id));
-                memset(id, 0, sizeof(*id));
+                id = xcalloc(1, sizeof(*id));
                 id->key = key;
                 id->filename = xstrdup(options.identity_files[i]);
                 TAILQ_INSERT_TAIL(&files, id, next);
@@ -1142,8 +1158,7 @@ pubkey_prepare(Authctxt *authctxt)
                                 }
                         }
                         if (!found && !options.identities_only) {
-                                id = xmalloc(sizeof(*id));
-                                memset(id, 0, sizeof(*id));
+                                id = xcalloc(1, sizeof(*id));
                                 id->key = key;
                                 id->filename = comment;
                                 id->ac = ac;
@@ -1339,8 +1354,7 @@ ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
                 return -1;
         }
         if (pid == 0) {
-                seteuid(getuid());
-                setuid(getuid());
+                permanently_drop_suid(getuid());
                 close(from[0]);
                 if (dup2(from[1], STDOUT_FILENO) < 0)
                         fatal("ssh_keysign: dup2: %s", strerror(errno));
@@ -1420,12 +1434,11 @@ userauth_hostbased(Authctxt *authctxt)
         if (p == NULL) {
                 error("userauth_hostbased: cannot get local ipaddr/name");
                 key_free(private);
+                xfree(blob);
                 return 0;
         }
         len = strlen(p) + 2;
-        chost = xmalloc(len);
-        strlcpy(chost, p, len);
-        strlcat(chost, ".", len);
+        xasprintf(&chost, "%s.", p);
         debug2("userauth_hostbased: chost %s", chost);
         xfree(p);
 
@@ -1458,6 +1471,7 @@ userauth_hostbased(Authctxt *authctxt)
                 error("key_sign failed");
                 xfree(chost);
                 xfree(pkalg);
+                xfree(blob);
                 return 0;
         }
         packet_start(SSH2_MSG_USERAUTH_REQUEST);
@@ -1473,6 +1487,7 @@ userauth_hostbased(Authctxt *authctxt)
         xfree(signature);
         xfree(chost);
         xfree(pkalg);
+        xfree(blob);
 
         packet_send();
         return 1;