1 files changed, 225 insertions, 119 deletions

diff --git a/ssh.c b/ssh.c
index 9cb211716..e36debf6a 100644
--- a/ssh.c
+++ b/ssh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh.c,v 1.464 2017/09/21 19:16:53 markus Exp $ */
+/* $OpenBSD: ssh.c,v 1.475 2018/02/23 15:58:38 markus Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -168,6 +168,10 @@ char *config = NULL;
  */
 char *host;
 
+/* Various strings used to to percent_expand() arguments */
+static char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
+static char uidstr[32], *host_arg, *conn_hash_hex;
+
 /* socket address the host resolves to */
 struct sockaddr_storage hostaddr;
 
@@ -197,19 +201,19 @@ static void
 usage(void)
 {
         fprintf(stderr,
-"usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
-"           [-D [bind_address:]port] [-E log_file] [-e escape_char]\n"
-"           [-F configfile] [-I pkcs11] [-i identity_file]\n"
-"           [-J [user@]host[:port]] [-L address] [-l login_name] [-m mac_spec]\n"
-"           [-O ctl_cmd] [-o option] [-p port] [-Q query_option] [-R address]\n"
-"           [-S ctl_path] [-W host:port] [-w local_tun[:remote_tun]]\n"
-"           [user@]hostname [command]\n"
+"usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface]\n"
+"           [-b bind_address] [-c cipher_spec] [-D [bind_address:]port]\n"
+"           [-E log_file] [-e escape_char] [-F configfile] [-I pkcs11]\n"
+"           [-i identity_file] [-J [user@]host[:port]] [-L address]\n"
+"           [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
+"           [-Q query_option] [-R address] [-S ctl_path] [-W host:port]\n"
+"           [-w local_tun[:remote_tun]] destination [command]\n"
         );
         exit(255);
 }
 
-static int ssh_session2(struct ssh *);
-static void load_public_identity_files(void);
+static int ssh_session2(struct ssh *, struct passwd *);
+static void load_public_identity_files(struct passwd *);
 static void main_sigchld_handler(int);
 
 /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
@@ -267,6 +271,40 @@ resolve_host(const char *name, int port, int logerr, char *cname, size_t clen)
         return res;
 }
 
+/* Returns non-zero if name can only be an address and not a hostname */
+static int
+is_addr_fast(const char *name)
+{
+        return (strchr(name, '%') != NULL || strchr(name, ':') != NULL ||
+            strspn(name, "0123456789.") == strlen(name));
+}
+
+/* Returns non-zero if name represents a valid, single address */
+static int
+is_addr(const char *name)
+{
+        char strport[NI_MAXSERV];
+        struct addrinfo hints, *res;
+
+        if (is_addr_fast(name))
+                return 1;
+
+        snprintf(strport, sizeof strport, "%u", default_ssh_port());
+        memset(&hints, 0, sizeof(hints));
+        hints.ai_family = options.address_family == -1 ?
+            AF_UNSPEC : options.address_family;
+        hints.ai_socktype = SOCK_STREAM;
+        hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
+        if (getaddrinfo(name, strport, &hints, &res) != 0)
+                return 0;
+        if (res == NULL || res->ai_next != NULL) {
+                freeaddrinfo(res);
+                return 0;
+        }
+        freeaddrinfo(res);
+        return 1;
+}
+
 /*
  * Attempt to resolve a numeric host address / port to a single address.
  * Returns a canonical address string.
@@ -372,20 +410,10 @@ resolve_canonicalize(char **hostp, int port)
         char *cp, *fullhost, newname[NI_MAXHOST];
         struct addrinfo *addrs;
 
-        if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
-                return NULL;
-
         /*
-         * Don't attempt to canonicalize names that will be interpreted by
-         * a proxy unless the user specifically requests so.
+         * Attempt to canonicalise addresses, regardless of
+         * whether hostname canonicalisation was requested
          */
-        direct = option_clear_or_none(options.proxy_command) &&
-            options.jump_host == NULL;
-        if (!direct &&
-            options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
-                return NULL;
-
-        /* Try numeric hostnames first */
         if ((addrs = resolve_addr(*hostp, port,
             newname, sizeof(newname))) != NULL) {
                 debug2("%s: hostname %.100s is address", __func__, *hostp);
@@ -398,6 +426,30 @@ resolve_canonicalize(char **hostp, int port)
                 return addrs;
         }
 
+        /*
+         * If this looks like an address but didn't parse as one, it might
+         * be an address with an invalid interface scope. Skip further
+         * attempts at canonicalisation.
+         */
+        if (is_addr_fast(*hostp)) {
+                debug("%s: hostname %.100s is an unrecognised address",
+                    __func__, *hostp);
+                return NULL;
+        }
+
+        if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
+                return NULL;
+
+        /*
+         * Don't attempt to canonicalize names that will be interpreted by
+         * a proxy unless the user specifically requests so.
+         */
+        direct = option_clear_or_none(options.proxy_command) &&
+            options.jump_host == NULL;
+        if (!direct &&
+            options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
+                return NULL;
+
         /* If domain name is anchored, then resolve it now */
         if ((*hostp)[strlen(*hostp) - 1] == '.') {
                 debug3("%s: name is fully qualified", __func__);
@@ -456,14 +508,14 @@ resolve_canonicalize(char **hostp, int port)
  * file if the user specifies a config file on the command line.
  */
 static void
-process_config_files(const char *host_arg, struct passwd *pw, int post_canon)
+process_config_files(const char *host_name, struct passwd *pw, int post_canon)
 {
         char buf[PATH_MAX];
         int r;
 
         if (config != NULL) {
                 if (strcasecmp(config, "none") != 0 &&
-                    !read_config_file(config, pw, host, host_arg, &options,
+                    !read_config_file(config, pw, host, host_name, &options,
                     SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0)))
                         fatal("Can't open user config file %.100s: "
                             "%.100s", config, strerror(errno));
@@ -471,13 +523,13 @@ process_config_files(const char *host_arg, struct passwd *pw, int post_canon)
                 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
                     _PATH_SSH_USER_CONFFILE);
                 if (r > 0 && (size_t)r < sizeof(buf))
-                        (void)read_config_file(buf, pw, host, host_arg,
+                        (void)read_config_file(buf, pw, host, host_name,
                             &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF |
                             (post_canon ? SSHCONF_POSTCANON : 0));
 
                 /* Read systemwide configuration file after user config. */
                 (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw,
-                    host, host_arg, &options,
+                    host, host_name, &options,
                     post_canon ? SSHCONF_POSTCANON : 0);
         }
 }
@@ -510,10 +562,9 @@ main(int ac, char **av)
 {
         struct ssh *ssh = NULL;
         int i, r, opt, exit_status, use_syslog, direct, timeout_ms;
-        int config_test = 0, opt_terminated = 0;
-        char *p, *cp, *line, *argv0, buf[PATH_MAX], *host_arg, *logfile;
-        char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
-        char cname[NI_MAXHOST], uidstr[32], *conn_hash_hex;
+        int was_addr, config_test = 0, opt_terminated = 0;
+        char *p, *cp, *line, *argv0, buf[PATH_MAX], *logfile;
+        char cname[NI_MAXHOST];
         struct stat st;
         struct passwd *pw;
         extern int optind, optreset;
@@ -612,7 +663,7 @@ main(int ac, char **av)
 
  again:
         while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
-            "ACD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
+            "AB:CD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
                 switch (opt) {
                 case '1':
                         fatal("SSH protocol v.1 is no longer supported");
@@ -846,14 +897,18 @@ main(int ac, char **av)
                                 options.control_master = SSHCTL_MASTER_YES;
                         break;
                 case 'p':
-                        options.port = a2port(optarg);
-                        if (options.port <= 0) {
-                                fprintf(stderr, "Bad port '%s'\n", optarg);
-                                exit(255);
+                        if (options.port == -1) {
+                                options.port = a2port(optarg);
+                                if (options.port <= 0) {
+                                        fprintf(stderr, "Bad port '%s'\n",
+                                            optarg);
+                                        exit(255);
+                                }
                         }
                         break;
                 case 'l':
-                        options.user = optarg;
+                        if (options.user == NULL)
+                                options.user = optarg;
                         break;
 
                 case 'L':
@@ -918,6 +973,9 @@ main(int ac, char **av)
                 case 'b':
                         options.bind_address = optarg;
                         break;
+                case 'B':
+                        options.bind_interface = optarg;
+                        break;
                 case 'F':
                         config = optarg;
                         break;
@@ -933,16 +991,38 @@ main(int ac, char **av)
         av += optind;
 
         if (ac > 0 && !host) {
-                if (strrchr(*av, '@')) {
+                int tport;
+                char *tuser;
+                switch (parse_ssh_uri(*av, &tuser, &host, &tport)) {
+                case -1:
+                        usage();
+                        break;
+                case 0:
+                        if (options.user == NULL) {
+                                options.user = tuser;
+                                tuser = NULL;
+                        }
+                        free(tuser);
+                        if (options.port == -1 && tport != -1)
+                                options.port = tport;
+                        break;
+                default:
                         p = xstrdup(*av);
                         cp = strrchr(p, '@');
-                        if (cp == NULL || cp == p)
-                                usage();
-                        options.user = p;
-                        *cp = '\0';
-                        host = xstrdup(++cp);
-                } else
-                        host = xstrdup(*av);
+                        if (cp != NULL) {
+                                if (cp == p)
+                                        usage();
+                                if (options.user == NULL) {
+                                        options.user = p;
+                                        p = NULL;
+                                }
+                                *cp++ = '\0';
+                                host = xstrdup(cp);
+                                free(p);
+                        } else
+                                host = p;
+                        break;
+                }
                 if (ac > 1 && !opt_terminated) {
                         optind = optreset = 1;
                         goto again;
@@ -994,9 +1074,9 @@ main(int ac, char **av)
         if (logfile != NULL)
                 log_redirect_stderr_to(logfile);
         log_init(argv0,
-            options.log_level == SYSLOG_LEVEL_NOT_SET ? 
+            options.log_level == SYSLOG_LEVEL_NOT_SET ?
             SYSLOG_LEVEL_INFO : options.log_level,
-            options.log_facility == SYSLOG_FACILITY_NOT_SET ? 
+            options.log_facility == SYSLOG_FACILITY_NOT_SET ?
             SYSLOG_FACILITY_USER : options.log_facility,
             !use_syslog);
 
@@ -1026,16 +1106,22 @@ main(int ac, char **av)
                 options.hostname = xstrdup(host);
         }
 
-        /* If canonicalization requested then try to apply it */
-        lowercase(host);
-        if (options.canonicalize_hostname != SSH_CANONICALISE_NO)
+        /* Don't lowercase addresses, they will be explicitly canonicalised */
+        if ((was_addr = is_addr(host)) == 0)
+                lowercase(host);
+
+        /*
+         * Try to canonicalize if requested by configuration or the
+         * hostname is an address.
+         */
+        if (options.canonicalize_hostname != SSH_CANONICALISE_NO || was_addr)
                 addrs = resolve_canonicalize(&host, options.port);
 
         /*
          * If CanonicalizePermittedCNAMEs have been specified but
          * other canonicalization did not happen (by not being requested
          * or by failing with fallback) then the hostname may still be changed
-         * as a result of CNAME following. 
+         * as a result of CNAME following.
          *
          * Try to resolve the bare hostname name using the system resolver's
          * usual search rules and then apply the CNAME follow rules.
@@ -1177,6 +1263,7 @@ main(int ac, char **av)
         if (options.user == NULL)
                 options.user = xstrdup(pw->pw_name);
 
+        /* Set up strings used to percent_expand() arguments */
         if (gethostname(thishost, sizeof(thishost)) == -1)
                 fatal("gethostname: %s", strerror(errno));
         strlcpy(shorthost, thishost, sizeof(shorthost));
@@ -1194,24 +1281,11 @@ main(int ac, char **av)
         ssh_digest_free(md);
         conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1));
 
-        if (options.local_command != NULL) {
-                debug3("expanding LocalCommand: %s", options.local_command);
-                cp = options.local_command;
-                options.local_command = percent_expand(cp,
-                    "C", conn_hash_hex,
-                    "L", shorthost,
-                    "d", pw->pw_dir,
-                    "h", host,
-                    "l", thishost,
-                    "n", host_arg,
-                    "p", portstr,
-                    "r", options.user,
-                    "u", pw->pw_name,
-                    (char *)NULL);
-                debug3("expanded LocalCommand: %s", options.local_command);
-                free(cp);
-        }
-
+        /*
+         * Expand tokens in arguments. NB. LocalCommand is expanded later,
+         * after port-forwarding is set up, so it may pick up any local
+         * tunnel interface name allocated.
+         */
         if (options.remote_command != NULL) {
                 debug3("expanding RemoteCommand: %s", options.remote_command);
                 cp = options.remote_command;
@@ -1230,7 +1304,6 @@ main(int ac, char **av)
                 free(cp);
                 buffer_append(&command, options.remote_command,
                     strlen(options.remote_command));
-
         }
 
         if (options.control_path != NULL) {
@@ -1311,7 +1384,7 @@ main(int ac, char **av)
         sensitive_data.keys = NULL;
         sensitive_data.external_keysign = 0;
         if (options.hostbased_authentication) {
-                sensitive_data.nkeys = 9;
+                sensitive_data.nkeys = 11;
                 sensitive_data.keys = xcalloc(sensitive_data.nkeys,
                     sizeof(struct sshkey));     /* XXX */
                 for (i = 0; i < sensitive_data.nkeys; i++)
@@ -1338,6 +1411,10 @@ main(int ac, char **av)
                     _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
                 sensitive_data.keys[8] = key_load_private_type(KEY_DSA,
                     _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
+                sensitive_data.keys[9] = key_load_private_cert(KEY_XMSS,
+                    _PATH_HOST_XMSS_KEY_FILE, "", NULL);
+                sensitive_data.keys[10] = key_load_private_type(KEY_XMSS,
+                    _PATH_HOST_XMSS_KEY_FILE, "", NULL, NULL);
                 PRIV_END;
 
                 if (options.hostbased_authentication == 1 &&
@@ -1345,7 +1422,8 @@ main(int ac, char **av)
                     sensitive_data.keys[5] == NULL &&
                     sensitive_data.keys[6] == NULL &&
                     sensitive_data.keys[7] == NULL &&
-                    sensitive_data.keys[8] == NULL) {
+                    sensitive_data.keys[8] == NULL &&
+                    sensitive_data.keys[9] == NULL) {
 #ifdef OPENSSL_HAS_ECC
                         sensitive_data.keys[1] = key_load_cert(
                             _PATH_HOST_ECDSA_KEY_FILE);
@@ -1366,6 +1444,10 @@ main(int ac, char **av)
                             _PATH_HOST_RSA_KEY_FILE, NULL);
                         sensitive_data.keys[8] = key_load_public(
                             _PATH_HOST_DSA_KEY_FILE, NULL);
+                        sensitive_data.keys[9] = key_load_cert(
+                            _PATH_HOST_XMSS_KEY_FILE);
+                        sensitive_data.keys[10] = key_load_public(
+                            _PATH_HOST_XMSS_KEY_FILE, NULL);
                         sensitive_data.external_keysign = 1;
                 }
         }
@@ -1401,7 +1483,7 @@ main(int ac, char **av)
                 }
         }
         /* load options.identity_files */
-        load_public_identity_files();
+        load_public_identity_files(pw);
 
         /* optionally set the SSH_AUTHSOCKET_ENV_NAME varibale */
         if (options.identity_agent &&
@@ -1465,7 +1547,7 @@ main(int ac, char **av)
         }
 
  skip_connect:
-        exit_status = ssh_session2(ssh);
+        exit_status = ssh_session2(ssh, pw);
         packet_close();
 
         if (options.control_path != NULL && muxserver_sock != -1)
@@ -1485,29 +1567,29 @@ control_persist_detach(void)
 
         debug("%s: backgrounding master process", __func__);
 
-        /*
-         * master (current process) into the background, and make the
-         * foreground process a client of the backgrounded master.
-         */
+        /*
+         * master (current process) into the background, and make the
+         * foreground process a client of the backgrounded master.
+         */
         switch ((pid = fork())) {
         case -1:
                 fatal("%s: fork: %s", __func__, strerror(errno));
         case 0:
                 /* Child: master process continues mainloop */
-                break;
-        default:
+                break;
+        default:
                 /* Parent: set up mux slave to connect to backgrounded master */
                 debug2("%s: background process is %ld", __func__, (long)pid);
                 stdin_null_flag = ostdin_null_flag;
                 options.request_tty = orequest_tty;
                 tty_flag = otty_flag;
-                close(muxserver_sock);
-                muxserver_sock = -1;
+                close(muxserver_sock);
+                muxserver_sock = -1;
                 options.control_master = SSHCTL_MASTER_NO;
-                muxclient(options.control_path);
+                muxclient(options.control_path);
                 /* muxclient() doesn't return on success. */
-                fatal("Failed to connect to new control master");
-        }
+                fatal("Failed to connect to new control master");
+        }
         if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
                 error("%s: open(\"/dev/null\"): %s", __func__,
                     strerror(errno));
@@ -1562,7 +1644,7 @@ ssh_confirm_remote_forward(struct ssh *ssh, int type, u_int32_t seq, void *ctxt)
                         channel_update_permitted_opens(ssh, rfwd->handle, -1);
                 }
         }
-        
+
         if (type == SSH2_MSG_REQUEST_FAILURE) {
                 if (options.exit_on_forward_failure) {
                         if (rfwd->listen_path != NULL)
@@ -1624,7 +1706,7 @@ ssh_init_stdio_forwarding(struct ssh *ssh)
 }
 
 static void
-ssh_init_forwarding(struct ssh *ssh)
+ssh_init_forwarding(struct ssh *ssh, char **ifname)
 {
         int success = 0;
         int i;
@@ -1682,14 +1764,15 @@ ssh_init_forwarding(struct ssh *ssh)
 
         /* Initiate tunnel forwarding. */
         if (options.tun_open != SSH_TUNMODE_NO) {
-                if (client_request_tun_fwd(ssh, options.tun_open,
-                    options.tun_local, options.tun_remote) == -1) {
+                if ((*ifname = client_request_tun_fwd(ssh,
+                    options.tun_open, options.tun_local,
+                    options.tun_remote)) == NULL) {
                         if (options.exit_on_forward_failure)
                                 fatal("Could not request tunnel forwarding.");
                         else
                                 error("Could not request tunnel forwarding.");
                 }
-        }                       
+        }
 }
 
 static void
@@ -1798,20 +1881,41 @@ ssh_session2_open(struct ssh *ssh)
 }
 
 static int
-ssh_session2(struct ssh *ssh)
+ssh_session2(struct ssh *ssh, struct passwd *pw)
 {
-        int id = -1;
+        int devnull, id = -1;
+        char *cp, *tun_fwd_ifname = NULL;
 
         /* XXX should be pre-session */
         if (!options.control_persist)
                 ssh_init_stdio_forwarding(ssh);
-        ssh_init_forwarding(ssh);
+
+        ssh_init_forwarding(ssh, &tun_fwd_ifname);
+
+        if (options.local_command != NULL) {
+                debug3("expanding LocalCommand: %s", options.local_command);
+                cp = options.local_command;
+                options.local_command = percent_expand(cp,
+                    "C", conn_hash_hex,
+                    "L", shorthost,
+                    "d", pw->pw_dir,
+                    "h", host,
+                    "l", thishost,
+                    "n", host_arg,
+                    "p", portstr,
+                    "r", options.user,
+                    "u", pw->pw_name,
+                    "T", tun_fwd_ifname == NULL ? "NONE" : tun_fwd_ifname,
+                    (char *)NULL);
+                debug3("expanded LocalCommand: %s", options.local_command);
+                free(cp);
+        }
 
         /* Start listening for multiplex clients */
         if (!packet_get_mux())
                 muxserver_listen(ssh);
 
-        /*
+        /*
          * If we are in control persist mode and have a working mux listen
          * socket, then prepare to background ourselves and have a foreground
          * client attach as a control slave.
@@ -1820,18 +1924,18 @@ ssh_session2(struct ssh *ssh)
          * after the connection is fully established (in particular,
          * async rfwd replies have been received for ExitOnForwardFailure).
          */
-        if (options.control_persist && muxserver_sock != -1) {
+        if (options.control_persist && muxserver_sock != -1) {
                 ostdin_null_flag = stdin_null_flag;
                 ono_shell_flag = no_shell_flag;
                 orequest_tty = options.request_tty;
                 otty_flag = tty_flag;
-                stdin_null_flag = 1;
-                no_shell_flag = 1;
-                tty_flag = 0;
+                stdin_null_flag = 1;
+                no_shell_flag = 1;
+                tty_flag = 0;
                 if (!fork_after_authentication_flag)
                         need_controlpersist_detach = 1;
                 fork_after_authentication_flag = 1;
-        }
+        }
         /*
          * ControlPersist mux listen socket setup failed, attempt the
          * stdio forward setup that we skipped earlier.
@@ -1839,7 +1943,7 @@ ssh_session2(struct ssh *ssh)
         if (options.control_persist && muxserver_sock == -1)
                 ssh_init_stdio_forwarding(ssh);
 
-        if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
+        if (!no_shell_flag)
                 id = ssh_session2_open(ssh);
         else {
                 packet_set_interactive(
@@ -1863,6 +1967,22 @@ ssh_session2(struct ssh *ssh)
                 ssh_local_cmd(options.local_command);
 
         /*
+         * stdout is now owned by the session channel; clobber it here
+         * so future channel closes are propagated to the local fd.
+         * NB. this can only happen after LocalCommand has completed,
+         * as it may want to write to stdout.
+         */
+        if (!need_controlpersist_detach) {
+                if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1)
+                        error("%s: open %s: %s", __func__,
+                            _PATH_DEVNULL, strerror(errno));
+                if (dup2(devnull, STDOUT_FILENO) < 0)
+                        fatal("%s: dup2() stdout failed", __func__);
+                if (devnull > STDERR_FILENO)
+                        close(devnull);
+        }
+
+        /*
          * If requested and we are not interested in replies to remote
          * forwarding requests, then let ssh continue in the background.
          */
@@ -1881,12 +2001,10 @@ ssh_session2(struct ssh *ssh)
 
 /* Loads all IdentityFile and CertificateFile keys */
 static void
-load_public_identity_files(void)
+load_public_identity_files(struct passwd *pw)
 {
-        char *filename, *cp, thishost[NI_MAXHOST];
-        char *pwdir = NULL, *pwname = NULL;
+        char *filename, *cp;
         struct sshkey *public;
-        struct passwd *pw;
         int i;
         u_int n_ids, n_certs;
         char *identity_files[SSH_MAX_IDENTITY_FILES];
@@ -1925,11 +2043,6 @@ load_public_identity_files(void)
 #endif /* ENABLE_PKCS11 */
         if ((pw = getpwuid(original_real_uid)) == NULL)
                 fatal("load_public_identity_files: getpwuid failed");
-        pwname = xstrdup(pw->pw_name);
-        pwdir = xstrdup(pw->pw_dir);
-        if (gethostname(thishost, sizeof(thishost)) == -1)
-                fatal("load_public_identity_files: gethostname: %s",
-                    strerror(errno));
         for (i = 0; i < options.num_identity_files; i++) {
                 if (n_ids >= SSH_MAX_IDENTITY_FILES ||
                     strcasecmp(options.identity_files[i], "none") == 0) {
@@ -1939,8 +2052,8 @@ load_public_identity_files(void)
                 }
                 cp = tilde_expand_filename(options.identity_files[i],
                     original_real_uid);
-                filename = percent_expand(cp, "d", pwdir,
-                    "u", pwname, "l", thishost, "h", host,
+                filename = percent_expand(cp, "d", pw->pw_dir,
+                    "u", pw->pw_name, "l", thishost, "h", host,
                     "r", options.user, (char *)NULL);
                 free(cp);
                 public = key_load_public(filename, NULL);
@@ -1985,8 +2098,8 @@ load_public_identity_files(void)
         for (i = 0; i < options.num_certificate_files; i++) {
                 cp = tilde_expand_filename(options.certificate_files[i],
                     original_real_uid);
-                filename = percent_expand(cp, "d", pwdir,
-                    "u", pwname, "l", thishost, "h", host,
+                filename = percent_expand(cp, "d", pw->pw_dir,
+                    "u", pw->pw_name, "l", thishost, "h", host,
                     "r", options.user, (char *)NULL);
                 free(cp);
 
@@ -2019,11 +2132,6 @@ load_public_identity_files(void)
         memcpy(options.certificate_files,
             certificate_files, sizeof(certificate_files));
         memcpy(options.certificates, certificates, sizeof(certificates));
-
-        explicit_bzero(pwname, strlen(pwname));
-        free(pwname);
-        explicit_bzero(pwdir, strlen(pwdir));
-        free(pwdir);
 }
 
 static void
@@ -2036,7 +2144,5 @@ main_sigchld_handler(int sig)
         while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
             (pid < 0 && errno == EINTR))
                 ;
-
-        signal(sig, main_sigchld_handler);
         errno = save_errno;
 }