From 9c38643c5cd47a19db2cc28279dcc28abadc22b3 Mon Sep 17 00:00:00 2001 From: Damien Miller Date: Thu, 3 Jul 2014 21:27:46 +1000 Subject: - djm@cvs.openbsd.org 2014/07/03 06:39:19 [ssh.c ssh_config.5] Add a %C escape sequence for LocalCommand and ControlPath that expands to a unique identifer based on a has of the tuple of (local host, remote user, hostname, port). Helps avoid exceeding sockaddr_un's miserly pathname limits for mux control paths. bz#2220, based on patch from mancha1 AT zoho.com; ok markus@ --- ssh.c | 43 ++++++++++++++++++++++++++++++++++++------- 1 file changed, 36 insertions(+), 7 deletions(-) (limited to 'ssh.c') diff --git a/ssh.c b/ssh.c index 6625557bd..54f1dbd0a 100644 --- a/ssh.c +++ b/ssh.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh.c,v 1.404 2014/06/27 16:41:56 markus Exp $ */ +/* $OpenBSD: ssh.c,v 1.405 2014/07/03 06:39:19 djm Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -85,6 +85,7 @@ #include "canohost.h" #include "compat.h" #include "cipher.h" +#include "digest.h" #include "packet.h" #include "buffer.h" #include "channels.h" @@ -424,6 +425,9 @@ main(int ac, char **av) extern char *optarg; Forward fwd; struct addrinfo *addrs = NULL; + struct ssh_digest_ctx *md; + u_char conn_hash[SSH_DIGEST_MAX_LENGTH]; + char *conn_hash_hex; /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ sanitise_stdfd(); @@ -1002,12 +1006,29 @@ main(int ac, char **av) shorthost[strcspn(thishost, ".")] = '\0'; snprintf(portstr, sizeof(portstr), "%d", options.port); + if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL || + ssh_digest_update(md, thishost, strlen(thishost)) < 0 || + ssh_digest_update(md, host, strlen(host)) < 0 || + ssh_digest_update(md, portstr, strlen(portstr)) < 0 || + ssh_digest_update(md, options.user, strlen(options.user)) < 0 || + ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0) + fatal("%s: mux digest failed", __func__); + 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, "d", pw->pw_dir, - "h", host, "l", thishost, "n", host_arg, "r", options.user, - "p", portstr, "u", pw->pw_name, "L", shorthost, + 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); @@ -1017,12 +1038,20 @@ main(int ac, char **av) cp = tilde_expand_filename(options.control_path, original_real_uid); free(options.control_path); - options.control_path = percent_expand(cp, "h", host, - "l", thishost, "n", host_arg, "r", options.user, - "p", portstr, "u", pw->pw_name, "L", shorthost, + options.control_path = percent_expand(cp, + "C", conn_hash_hex, + "L", shorthost, + "h", host, + "l", thishost, + "n", host_arg, + "p", portstr, + "r", options.user, + "u", pw->pw_name, (char *)NULL); free(cp); } + free(conn_hash_hex); + if (muxclient_command != 0 && options.control_path == NULL) fatal("No ControlPath specified for \"-O\" command"); if (options.control_path != NULL) -- cgit v1.2.3