1417 lines
35 KiB
C
1417 lines
35 KiB
C
/* $OpenBSD: ssh-agent.c,v 1.199 2015/03/04 21:12:59 djm Exp $ */
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/*
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* Author: Tatu Ylonen <ylo@cs.hut.fi>
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* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
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* All rights reserved
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* The authentication agent program.
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*
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* As far as I am concerned, the code I have written for this software
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* can be used freely for any purpose. Any derived versions of this
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* software must be clearly marked as such, and if the derived work is
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* incompatible with the protocol description in the RFC file, it must be
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* called by a name other than "ssh" or "Secure Shell".
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*
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* Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "includes.h"
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__RCSID("$FreeBSD$");
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#include <sys/param.h> /* MIN MAX */
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#include <sys/types.h>
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#include <sys/param.h>
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#include <sys/resource.h>
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#include <sys/stat.h>
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#include <sys/socket.h>
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#ifdef HAVE_SYS_TIME_H
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# include <sys/time.h>
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#endif
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#ifdef HAVE_SYS_UN_H
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# include <sys/un.h>
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#endif
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#include "openbsd-compat/sys-queue.h"
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#ifdef WITH_OPENSSL
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#include <openssl/evp.h>
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#include "openbsd-compat/openssl-compat.h"
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#endif
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#include <errno.h>
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#include <fcntl.h>
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#include <limits.h>
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#ifdef HAVE_PATHS_H
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# include <paths.h>
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#endif
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#include <signal.h>
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#include <stdarg.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <time.h>
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#include <string.h>
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#include <unistd.h>
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#include "key.h" /* XXX for typedef */
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#include "buffer.h" /* XXX for typedef */
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#include "xmalloc.h"
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#include "ssh.h"
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#include "rsa.h"
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#include "sshbuf.h"
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#include "sshkey.h"
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#include "authfd.h"
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#include "compat.h"
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#include "log.h"
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#include "misc.h"
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#include "digest.h"
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#include "ssherr.h"
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#ifdef ENABLE_PKCS11
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#include "ssh-pkcs11.h"
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#endif
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#if defined(HAVE_SYS_PRCTL_H)
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#include <sys/prctl.h> /* For prctl() and PR_SET_DUMPABLE */
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#endif
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typedef enum {
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AUTH_UNUSED,
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AUTH_SOCKET,
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AUTH_CONNECTION
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} sock_type;
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typedef struct {
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int fd;
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sock_type type;
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struct sshbuf *input;
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struct sshbuf *output;
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struct sshbuf *request;
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} SocketEntry;
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u_int sockets_alloc = 0;
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SocketEntry *sockets = NULL;
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typedef struct identity {
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TAILQ_ENTRY(identity) next;
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struct sshkey *key;
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char *comment;
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char *provider;
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time_t death;
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u_int confirm;
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} Identity;
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typedef struct {
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int nentries;
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TAILQ_HEAD(idqueue, identity) idlist;
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} Idtab;
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/* private key table, one per protocol version */
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Idtab idtable[3];
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int max_fd = 0;
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/* pid of shell == parent of agent */
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pid_t parent_pid = -1;
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time_t parent_alive_interval = 0;
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/* pid of process for which cleanup_socket is applicable */
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pid_t cleanup_pid = 0;
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/* pathname and directory for AUTH_SOCKET */
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char socket_name[PATH_MAX];
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char socket_dir[PATH_MAX];
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/* locking */
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int locked = 0;
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char *lock_passwd = NULL;
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extern char *__progname;
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/* Default lifetime in seconds (0 == forever) */
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static long lifetime = 0;
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static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
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/*
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* Client connection count; incremented in new_socket() and decremented in
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* close_socket(). When it reaches 0, ssh-agent will exit. Since it is
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* normally initialized to 1, it will never reach 0. However, if the -x
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* option is specified, it is initialized to 0 in main(); in that case,
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* ssh-agent will exit as soon as it has had at least one client but no
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* longer has any.
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*/
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static int xcount = 1;
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static void
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close_socket(SocketEntry *e)
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{
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int last = 0;
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if (e->type == AUTH_CONNECTION) {
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debug("xcount %d -> %d", xcount, xcount - 1);
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if (--xcount == 0)
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last = 1;
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}
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close(e->fd);
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e->fd = -1;
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e->type = AUTH_UNUSED;
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sshbuf_free(e->input);
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sshbuf_free(e->output);
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sshbuf_free(e->request);
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if (last)
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cleanup_exit(0);
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}
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static void
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idtab_init(void)
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{
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int i;
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for (i = 0; i <=2; i++) {
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TAILQ_INIT(&idtable[i].idlist);
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idtable[i].nentries = 0;
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}
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}
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/* return private key table for requested protocol version */
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static Idtab *
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idtab_lookup(int version)
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{
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if (version < 1 || version > 2)
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fatal("internal error, bad protocol version %d", version);
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return &idtable[version];
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}
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static void
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free_identity(Identity *id)
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{
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sshkey_free(id->key);
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free(id->provider);
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free(id->comment);
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free(id);
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}
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/* return matching private key for given public key */
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static Identity *
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lookup_identity(struct sshkey *key, int version)
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{
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Identity *id;
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Idtab *tab = idtab_lookup(version);
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TAILQ_FOREACH(id, &tab->idlist, next) {
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if (sshkey_equal(key, id->key))
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return (id);
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}
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return (NULL);
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}
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/* Check confirmation of keysign request */
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static int
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confirm_key(Identity *id)
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{
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char *p;
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int ret = -1;
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p = sshkey_fingerprint(id->key, fingerprint_hash, SSH_FP_DEFAULT);
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if (p != NULL &&
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ask_permission("Allow use of key %s?\nKey fingerprint %s.",
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id->comment, p))
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ret = 0;
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free(p);
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return (ret);
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}
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static void
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send_status(SocketEntry *e, int success)
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{
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int r;
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if ((r = sshbuf_put_u32(e->output, 1)) != 0 ||
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(r = sshbuf_put_u8(e->output, success ?
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SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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}
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/* send list of supported public keys to 'client' */
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static void
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process_request_identities(SocketEntry *e, int version)
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{
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Idtab *tab = idtab_lookup(version);
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Identity *id;
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struct sshbuf *msg;
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int r;
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if ((msg = sshbuf_new()) == NULL)
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fatal("%s: sshbuf_new failed", __func__);
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if ((r = sshbuf_put_u8(msg, (version == 1) ?
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SSH_AGENT_RSA_IDENTITIES_ANSWER :
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SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
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(r = sshbuf_put_u32(msg, tab->nentries)) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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TAILQ_FOREACH(id, &tab->idlist, next) {
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if (id->key->type == KEY_RSA1) {
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#ifdef WITH_SSH1
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if ((r = sshbuf_put_u32(msg,
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BN_num_bits(id->key->rsa->n))) != 0 ||
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(r = sshbuf_put_bignum1(msg,
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id->key->rsa->e)) != 0 ||
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(r = sshbuf_put_bignum1(msg,
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id->key->rsa->n)) != 0)
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fatal("%s: buffer error: %s",
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__func__, ssh_err(r));
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#endif
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} else {
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u_char *blob;
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size_t blen;
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if ((r = sshkey_to_blob(id->key, &blob, &blen)) != 0) {
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error("%s: sshkey_to_blob: %s", __func__,
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ssh_err(r));
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continue;
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}
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if ((r = sshbuf_put_string(msg, blob, blen)) != 0)
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fatal("%s: buffer error: %s",
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__func__, ssh_err(r));
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free(blob);
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}
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if ((r = sshbuf_put_cstring(msg, id->comment)) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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}
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if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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sshbuf_free(msg);
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}
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#ifdef WITH_SSH1
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/* ssh1 only */
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static void
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process_authentication_challenge1(SocketEntry *e)
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{
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u_char buf[32], mdbuf[16], session_id[16];
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u_int response_type;
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BIGNUM *challenge;
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Identity *id;
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int r, len;
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struct sshbuf *msg;
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struct ssh_digest_ctx *md;
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struct sshkey *key;
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if ((msg = sshbuf_new()) == NULL)
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fatal("%s: sshbuf_new failed", __func__);
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if ((key = sshkey_new(KEY_RSA1)) == NULL)
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fatal("%s: sshkey_new failed", __func__);
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if ((challenge = BN_new()) == NULL)
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fatal("%s: BN_new failed", __func__);
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if ((r = sshbuf_get_u32(e->request, NULL)) != 0 || /* ignored */
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(r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 ||
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(r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0 ||
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(r = sshbuf_get_bignum1(e->request, challenge)))
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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/* Only protocol 1.1 is supported */
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if (sshbuf_len(e->request) == 0)
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goto failure;
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if ((r = sshbuf_get(e->request, session_id, sizeof(session_id))) != 0 ||
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(r = sshbuf_get_u32(e->request, &response_type)) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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if (response_type != 1)
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goto failure;
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id = lookup_identity(key, 1);
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if (id != NULL && (!id->confirm || confirm_key(id) == 0)) {
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struct sshkey *private = id->key;
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/* Decrypt the challenge using the private key. */
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if ((r = rsa_private_decrypt(challenge, challenge,
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private->rsa) != 0)) {
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fatal("%s: rsa_public_encrypt: %s", __func__,
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ssh_err(r));
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goto failure; /* XXX ? */
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}
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/* The response is MD5 of decrypted challenge plus session id */
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len = BN_num_bytes(challenge);
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if (len <= 0 || len > 32) {
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logit("%s: bad challenge length %d", __func__, len);
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goto failure;
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}
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memset(buf, 0, 32);
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BN_bn2bin(challenge, buf + 32 - len);
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if ((md = ssh_digest_start(SSH_DIGEST_MD5)) == NULL ||
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ssh_digest_update(md, buf, 32) < 0 ||
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ssh_digest_update(md, session_id, 16) < 0 ||
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ssh_digest_final(md, mdbuf, sizeof(mdbuf)) < 0)
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fatal("%s: md5 failed", __func__);
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ssh_digest_free(md);
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/* Send the response. */
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if ((r = sshbuf_put_u8(msg, SSH_AGENT_RSA_RESPONSE)) != 0 ||
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(r = sshbuf_put(msg, mdbuf, sizeof(mdbuf))) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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goto send;
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}
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failure:
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/* Unknown identity or protocol error. Send failure. */
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if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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send:
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if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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sshkey_free(key);
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BN_clear_free(challenge);
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sshbuf_free(msg);
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}
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#endif
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/* ssh2 only */
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static void
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process_sign_request2(SocketEntry *e)
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{
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u_char *blob, *data, *signature = NULL;
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size_t blen, dlen, slen = 0;
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u_int compat = 0, flags;
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int r, ok = -1;
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struct sshbuf *msg;
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struct sshkey *key;
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struct identity *id;
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if ((msg = sshbuf_new()) == NULL)
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fatal("%s: sshbuf_new failed", __func__);
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if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0 ||
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(r = sshbuf_get_string(e->request, &data, &dlen)) != 0 ||
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(r = sshbuf_get_u32(e->request, &flags)) != 0)
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
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if (flags & SSH_AGENT_OLD_SIGNATURE)
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compat = SSH_BUG_SIGBLOB;
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if ((r = sshkey_from_blob(blob, blen, &key)) != 0) {
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error("%s: cannot parse key blob: %s", __func__, ssh_err(ok));
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goto send;
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}
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if ((id = lookup_identity(key, 2)) == NULL) {
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verbose("%s: %s key not found", __func__, sshkey_type(key));
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goto send;
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}
|
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if (id->confirm && confirm_key(id) != 0) {
|
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verbose("%s: user refused key", __func__);
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goto send;
|
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}
|
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if ((r = sshkey_sign(id->key, &signature, &slen,
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data, dlen, compat)) != 0) {
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error("%s: sshkey_sign: %s", __func__, ssh_err(ok));
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goto send;
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}
|
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/* Success */
|
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ok = 0;
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send:
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sshkey_free(key);
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if (ok == 0) {
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if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 ||
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(r = sshbuf_put_string(msg, signature, slen)) != 0)
|
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
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} else if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
|
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fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
|
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if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
|
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sshbuf_free(msg);
|
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free(data);
|
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free(blob);
|
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free(signature);
|
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}
|
|
|
|
/* shared */
|
|
static void
|
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process_remove_identity(SocketEntry *e, int version)
|
|
{
|
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size_t blen;
|
|
int r, success = 0;
|
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struct sshkey *key = NULL;
|
|
u_char *blob;
|
|
#ifdef WITH_SSH1
|
|
u_int bits;
|
|
#endif /* WITH_SSH1 */
|
|
|
|
switch (version) {
|
|
#ifdef WITH_SSH1
|
|
case 1:
|
|
if ((key = sshkey_new(KEY_RSA1)) == NULL) {
|
|
error("%s: sshkey_new failed", __func__);
|
|
return;
|
|
}
|
|
if ((r = sshbuf_get_u32(e->request, &bits)) != 0 ||
|
|
(r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 ||
|
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(r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
|
|
if (bits != sshkey_size(key))
|
|
logit("Warning: identity keysize mismatch: "
|
|
"actual %u, announced %u",
|
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sshkey_size(key), bits);
|
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break;
|
|
#endif /* WITH_SSH1 */
|
|
case 2:
|
|
if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
if ((r = sshkey_from_blob(blob, blen, &key)) != 0)
|
|
error("%s: sshkey_from_blob failed: %s",
|
|
__func__, ssh_err(r));
|
|
free(blob);
|
|
break;
|
|
}
|
|
if (key != NULL) {
|
|
Identity *id = lookup_identity(key, version);
|
|
if (id != NULL) {
|
|
/*
|
|
* We have this key. Free the old key. Since we
|
|
* don't want to leave empty slots in the middle of
|
|
* the array, we actually free the key there and move
|
|
* all the entries between the empty slot and the end
|
|
* of the array.
|
|
*/
|
|
Idtab *tab = idtab_lookup(version);
|
|
if (tab->nentries < 1)
|
|
fatal("process_remove_identity: "
|
|
"internal error: tab->nentries %d",
|
|
tab->nentries);
|
|
TAILQ_REMOVE(&tab->idlist, id, next);
|
|
free_identity(id);
|
|
tab->nentries--;
|
|
success = 1;
|
|
}
|
|
sshkey_free(key);
|
|
}
|
|
send_status(e, success);
|
|
}
|
|
|
|
static void
|
|
process_remove_all_identities(SocketEntry *e, int version)
|
|
{
|
|
Idtab *tab = idtab_lookup(version);
|
|
Identity *id;
|
|
|
|
/* Loop over all identities and clear the keys. */
|
|
for (id = TAILQ_FIRST(&tab->idlist); id;
|
|
id = TAILQ_FIRST(&tab->idlist)) {
|
|
TAILQ_REMOVE(&tab->idlist, id, next);
|
|
free_identity(id);
|
|
}
|
|
|
|
/* Mark that there are no identities. */
|
|
tab->nentries = 0;
|
|
|
|
/* Send success. */
|
|
send_status(e, 1);
|
|
}
|
|
|
|
/* removes expired keys and returns number of seconds until the next expiry */
|
|
static time_t
|
|
reaper(void)
|
|
{
|
|
time_t deadline = 0, now = monotime();
|
|
Identity *id, *nxt;
|
|
int version;
|
|
Idtab *tab;
|
|
|
|
for (version = 1; version < 3; version++) {
|
|
tab = idtab_lookup(version);
|
|
for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
|
|
nxt = TAILQ_NEXT(id, next);
|
|
if (id->death == 0)
|
|
continue;
|
|
if (now >= id->death) {
|
|
debug("expiring key '%s'", id->comment);
|
|
TAILQ_REMOVE(&tab->idlist, id, next);
|
|
free_identity(id);
|
|
tab->nentries--;
|
|
} else
|
|
deadline = (deadline == 0) ? id->death :
|
|
MIN(deadline, id->death);
|
|
}
|
|
}
|
|
if (deadline == 0 || deadline <= now)
|
|
return 0;
|
|
else
|
|
return (deadline - now);
|
|
}
|
|
|
|
/*
|
|
* XXX this and the corresponding serialisation function probably belongs
|
|
* in key.c
|
|
*/
|
|
#ifdef WITH_SSH1
|
|
static int
|
|
agent_decode_rsa1(struct sshbuf *m, struct sshkey **kp)
|
|
{
|
|
struct sshkey *k = NULL;
|
|
int r = SSH_ERR_INTERNAL_ERROR;
|
|
|
|
*kp = NULL;
|
|
if ((k = sshkey_new_private(KEY_RSA1)) == NULL)
|
|
return SSH_ERR_ALLOC_FAIL;
|
|
|
|
if ((r = sshbuf_get_u32(m, NULL)) != 0 || /* ignored */
|
|
(r = sshbuf_get_bignum1(m, k->rsa->n)) != 0 ||
|
|
(r = sshbuf_get_bignum1(m, k->rsa->e)) != 0 ||
|
|
(r = sshbuf_get_bignum1(m, k->rsa->d)) != 0 ||
|
|
(r = sshbuf_get_bignum1(m, k->rsa->iqmp)) != 0 ||
|
|
/* SSH1 and SSL have p and q swapped */
|
|
(r = sshbuf_get_bignum1(m, k->rsa->q)) != 0 || /* p */
|
|
(r = sshbuf_get_bignum1(m, k->rsa->p)) != 0) /* q */
|
|
goto out;
|
|
|
|
/* Generate additional parameters */
|
|
if ((r = rsa_generate_additional_parameters(k->rsa)) != 0)
|
|
goto out;
|
|
/* enable blinding */
|
|
if (RSA_blinding_on(k->rsa, NULL) != 1) {
|
|
r = SSH_ERR_LIBCRYPTO_ERROR;
|
|
goto out;
|
|
}
|
|
|
|
r = 0; /* success */
|
|
out:
|
|
if (r == 0)
|
|
*kp = k;
|
|
else
|
|
sshkey_free(k);
|
|
return r;
|
|
}
|
|
#endif /* WITH_SSH1 */
|
|
|
|
static void
|
|
process_add_identity(SocketEntry *e, int version)
|
|
{
|
|
Idtab *tab = idtab_lookup(version);
|
|
Identity *id;
|
|
int success = 0, confirm = 0;
|
|
u_int seconds;
|
|
char *comment = NULL;
|
|
time_t death = 0;
|
|
struct sshkey *k = NULL;
|
|
u_char ctype;
|
|
int r = SSH_ERR_INTERNAL_ERROR;
|
|
|
|
switch (version) {
|
|
#ifdef WITH_SSH1
|
|
case 1:
|
|
r = agent_decode_rsa1(e->request, &k);
|
|
break;
|
|
#endif /* WITH_SSH1 */
|
|
case 2:
|
|
r = sshkey_private_deserialize(e->request, &k);
|
|
break;
|
|
}
|
|
if (r != 0 || k == NULL ||
|
|
(r = sshbuf_get_cstring(e->request, &comment, NULL)) != 0) {
|
|
error("%s: decode private key: %s", __func__, ssh_err(r));
|
|
goto err;
|
|
}
|
|
|
|
while (sshbuf_len(e->request)) {
|
|
if ((r = sshbuf_get_u8(e->request, &ctype)) != 0) {
|
|
error("%s: buffer error: %s", __func__, ssh_err(r));
|
|
goto err;
|
|
}
|
|
switch (ctype) {
|
|
case SSH_AGENT_CONSTRAIN_LIFETIME:
|
|
if ((r = sshbuf_get_u32(e->request, &seconds)) != 0) {
|
|
error("%s: bad lifetime constraint: %s",
|
|
__func__, ssh_err(r));
|
|
goto err;
|
|
}
|
|
death = monotime() + seconds;
|
|
break;
|
|
case SSH_AGENT_CONSTRAIN_CONFIRM:
|
|
confirm = 1;
|
|
break;
|
|
default:
|
|
error("%s: Unknown constraint %d", __func__, ctype);
|
|
err:
|
|
sshbuf_reset(e->request);
|
|
free(comment);
|
|
sshkey_free(k);
|
|
goto send;
|
|
}
|
|
}
|
|
|
|
success = 1;
|
|
if (lifetime && !death)
|
|
death = monotime() + lifetime;
|
|
if ((id = lookup_identity(k, version)) == NULL) {
|
|
id = xcalloc(1, sizeof(Identity));
|
|
id->key = k;
|
|
TAILQ_INSERT_TAIL(&tab->idlist, id, next);
|
|
/* Increment the number of identities. */
|
|
tab->nentries++;
|
|
} else {
|
|
sshkey_free(k);
|
|
free(id->comment);
|
|
}
|
|
id->comment = comment;
|
|
id->death = death;
|
|
id->confirm = confirm;
|
|
send:
|
|
send_status(e, success);
|
|
}
|
|
|
|
/* XXX todo: encrypt sensitive data with passphrase */
|
|
static void
|
|
process_lock_agent(SocketEntry *e, int lock)
|
|
{
|
|
int r, success = 0;
|
|
char *passwd;
|
|
|
|
if ((r = sshbuf_get_cstring(e->request, &passwd, NULL)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
if (locked && !lock && strcmp(passwd, lock_passwd) == 0) {
|
|
locked = 0;
|
|
explicit_bzero(lock_passwd, strlen(lock_passwd));
|
|
free(lock_passwd);
|
|
lock_passwd = NULL;
|
|
success = 1;
|
|
} else if (!locked && lock) {
|
|
locked = 1;
|
|
lock_passwd = xstrdup(passwd);
|
|
success = 1;
|
|
}
|
|
explicit_bzero(passwd, strlen(passwd));
|
|
free(passwd);
|
|
send_status(e, success);
|
|
}
|
|
|
|
static void
|
|
no_identities(SocketEntry *e, u_int type)
|
|
{
|
|
struct sshbuf *msg;
|
|
int r;
|
|
|
|
if ((msg = sshbuf_new()) == NULL)
|
|
fatal("%s: sshbuf_new failed", __func__);
|
|
if ((r = sshbuf_put_u8(msg,
|
|
(type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
|
|
SSH_AGENT_RSA_IDENTITIES_ANSWER :
|
|
SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
|
|
(r = sshbuf_put_u32(msg, 0)) != 0 ||
|
|
(r = sshbuf_put_stringb(e->output, msg)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
sshbuf_free(msg);
|
|
}
|
|
|
|
#ifdef ENABLE_PKCS11
|
|
static void
|
|
process_add_smartcard_key(SocketEntry *e)
|
|
{
|
|
char *provider = NULL, *pin;
|
|
int r, i, version, count = 0, success = 0, confirm = 0;
|
|
u_int seconds;
|
|
time_t death = 0;
|
|
u_char type;
|
|
struct sshkey **keys = NULL, *k;
|
|
Identity *id;
|
|
Idtab *tab;
|
|
|
|
if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
|
|
(r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
|
|
while (sshbuf_len(e->request)) {
|
|
if ((r = sshbuf_get_u8(e->request, &type)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
switch (type) {
|
|
case SSH_AGENT_CONSTRAIN_LIFETIME:
|
|
if ((r = sshbuf_get_u32(e->request, &seconds)) != 0)
|
|
fatal("%s: buffer error: %s",
|
|
__func__, ssh_err(r));
|
|
death = monotime() + seconds;
|
|
break;
|
|
case SSH_AGENT_CONSTRAIN_CONFIRM:
|
|
confirm = 1;
|
|
break;
|
|
default:
|
|
error("process_add_smartcard_key: "
|
|
"Unknown constraint type %d", type);
|
|
goto send;
|
|
}
|
|
}
|
|
if (lifetime && !death)
|
|
death = monotime() + lifetime;
|
|
|
|
count = pkcs11_add_provider(provider, pin, &keys);
|
|
for (i = 0; i < count; i++) {
|
|
k = keys[i];
|
|
version = k->type == KEY_RSA1 ? 1 : 2;
|
|
tab = idtab_lookup(version);
|
|
if (lookup_identity(k, version) == NULL) {
|
|
id = xcalloc(1, sizeof(Identity));
|
|
id->key = k;
|
|
id->provider = xstrdup(provider);
|
|
id->comment = xstrdup(provider); /* XXX */
|
|
id->death = death;
|
|
id->confirm = confirm;
|
|
TAILQ_INSERT_TAIL(&tab->idlist, id, next);
|
|
tab->nentries++;
|
|
success = 1;
|
|
} else {
|
|
sshkey_free(k);
|
|
}
|
|
keys[i] = NULL;
|
|
}
|
|
send:
|
|
free(pin);
|
|
free(provider);
|
|
free(keys);
|
|
send_status(e, success);
|
|
}
|
|
|
|
static void
|
|
process_remove_smartcard_key(SocketEntry *e)
|
|
{
|
|
char *provider = NULL, *pin = NULL;
|
|
int r, version, success = 0;
|
|
Identity *id, *nxt;
|
|
Idtab *tab;
|
|
|
|
if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
|
|
(r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
free(pin);
|
|
|
|
for (version = 1; version < 3; version++) {
|
|
tab = idtab_lookup(version);
|
|
for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
|
|
nxt = TAILQ_NEXT(id, next);
|
|
/* Skip file--based keys */
|
|
if (id->provider == NULL)
|
|
continue;
|
|
if (!strcmp(provider, id->provider)) {
|
|
TAILQ_REMOVE(&tab->idlist, id, next);
|
|
free_identity(id);
|
|
tab->nentries--;
|
|
}
|
|
}
|
|
}
|
|
if (pkcs11_del_provider(provider) == 0)
|
|
success = 1;
|
|
else
|
|
error("process_remove_smartcard_key:"
|
|
" pkcs11_del_provider failed");
|
|
free(provider);
|
|
send_status(e, success);
|
|
}
|
|
#endif /* ENABLE_PKCS11 */
|
|
|
|
/* dispatch incoming messages */
|
|
|
|
static void
|
|
process_message(SocketEntry *e)
|
|
{
|
|
u_int msg_len;
|
|
u_char type;
|
|
const u_char *cp;
|
|
int r;
|
|
|
|
if (sshbuf_len(e->input) < 5)
|
|
return; /* Incomplete message. */
|
|
cp = sshbuf_ptr(e->input);
|
|
msg_len = PEEK_U32(cp);
|
|
if (msg_len > 256 * 1024) {
|
|
close_socket(e);
|
|
return;
|
|
}
|
|
if (sshbuf_len(e->input) < msg_len + 4)
|
|
return;
|
|
|
|
/* move the current input to e->request */
|
|
sshbuf_reset(e->request);
|
|
if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 ||
|
|
(r = sshbuf_get_u8(e->request, &type)) != 0)
|
|
fatal("%s: buffer error: %s", __func__, ssh_err(r));
|
|
|
|
/* check wheter agent is locked */
|
|
if (locked && type != SSH_AGENTC_UNLOCK) {
|
|
sshbuf_reset(e->request);
|
|
switch (type) {
|
|
case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
|
|
case SSH2_AGENTC_REQUEST_IDENTITIES:
|
|
/* send empty lists */
|
|
no_identities(e, type);
|
|
break;
|
|
default:
|
|
/* send a fail message for all other request types */
|
|
send_status(e, 0);
|
|
}
|
|
return;
|
|
}
|
|
|
|
debug("type %d", type);
|
|
switch (type) {
|
|
case SSH_AGENTC_LOCK:
|
|
case SSH_AGENTC_UNLOCK:
|
|
process_lock_agent(e, type == SSH_AGENTC_LOCK);
|
|
break;
|
|
#ifdef WITH_SSH1
|
|
/* ssh1 */
|
|
case SSH_AGENTC_RSA_CHALLENGE:
|
|
process_authentication_challenge1(e);
|
|
break;
|
|
case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
|
|
process_request_identities(e, 1);
|
|
break;
|
|
case SSH_AGENTC_ADD_RSA_IDENTITY:
|
|
case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED:
|
|
process_add_identity(e, 1);
|
|
break;
|
|
case SSH_AGENTC_REMOVE_RSA_IDENTITY:
|
|
process_remove_identity(e, 1);
|
|
break;
|
|
#endif
|
|
case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
|
|
process_remove_all_identities(e, 1); /* safe for !WITH_SSH1 */
|
|
break;
|
|
/* ssh2 */
|
|
case SSH2_AGENTC_SIGN_REQUEST:
|
|
process_sign_request2(e);
|
|
break;
|
|
case SSH2_AGENTC_REQUEST_IDENTITIES:
|
|
process_request_identities(e, 2);
|
|
break;
|
|
case SSH2_AGENTC_ADD_IDENTITY:
|
|
case SSH2_AGENTC_ADD_ID_CONSTRAINED:
|
|
process_add_identity(e, 2);
|
|
break;
|
|
case SSH2_AGENTC_REMOVE_IDENTITY:
|
|
process_remove_identity(e, 2);
|
|
break;
|
|
case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
|
|
process_remove_all_identities(e, 2);
|
|
break;
|
|
#ifdef ENABLE_PKCS11
|
|
case SSH_AGENTC_ADD_SMARTCARD_KEY:
|
|
case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
|
|
process_add_smartcard_key(e);
|
|
break;
|
|
case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
|
|
process_remove_smartcard_key(e);
|
|
break;
|
|
#endif /* ENABLE_PKCS11 */
|
|
default:
|
|
/* Unknown message. Respond with failure. */
|
|
error("Unknown message %d", type);
|
|
sshbuf_reset(e->request);
|
|
send_status(e, 0);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void
|
|
new_socket(sock_type type, int fd)
|
|
{
|
|
u_int i, old_alloc, new_alloc;
|
|
|
|
if (type == AUTH_CONNECTION) {
|
|
debug("xcount %d -> %d", xcount, xcount + 1);
|
|
++xcount;
|
|
}
|
|
set_nonblock(fd);
|
|
|
|
if (fd > max_fd)
|
|
max_fd = fd;
|
|
|
|
for (i = 0; i < sockets_alloc; i++)
|
|
if (sockets[i].type == AUTH_UNUSED) {
|
|
sockets[i].fd = fd;
|
|
if ((sockets[i].input = sshbuf_new()) == NULL)
|
|
fatal("%s: sshbuf_new failed", __func__);
|
|
if ((sockets[i].output = sshbuf_new()) == NULL)
|
|
fatal("%s: sshbuf_new failed", __func__);
|
|
if ((sockets[i].request = sshbuf_new()) == NULL)
|
|
fatal("%s: sshbuf_new failed", __func__);
|
|
sockets[i].type = type;
|
|
return;
|
|
}
|
|
old_alloc = sockets_alloc;
|
|
new_alloc = sockets_alloc + 10;
|
|
sockets = xrealloc(sockets, new_alloc, sizeof(sockets[0]));
|
|
for (i = old_alloc; i < new_alloc; i++)
|
|
sockets[i].type = AUTH_UNUSED;
|
|
sockets_alloc = new_alloc;
|
|
sockets[old_alloc].fd = fd;
|
|
if ((sockets[old_alloc].input = sshbuf_new()) == NULL)
|
|
fatal("%s: sshbuf_new failed", __func__);
|
|
if ((sockets[old_alloc].output = sshbuf_new()) == NULL)
|
|
fatal("%s: sshbuf_new failed", __func__);
|
|
if ((sockets[old_alloc].request = sshbuf_new()) == NULL)
|
|
fatal("%s: sshbuf_new failed", __func__);
|
|
sockets[old_alloc].type = type;
|
|
}
|
|
|
|
static int
|
|
prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
|
|
struct timeval **tvpp)
|
|
{
|
|
u_int i, sz;
|
|
int n = 0;
|
|
static struct timeval tv;
|
|
time_t deadline;
|
|
|
|
for (i = 0; i < sockets_alloc; i++) {
|
|
switch (sockets[i].type) {
|
|
case AUTH_SOCKET:
|
|
case AUTH_CONNECTION:
|
|
n = MAX(n, sockets[i].fd);
|
|
break;
|
|
case AUTH_UNUSED:
|
|
break;
|
|
default:
|
|
fatal("Unknown socket type %d", sockets[i].type);
|
|
break;
|
|
}
|
|
}
|
|
|
|
sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
|
|
if (*fdrp == NULL || sz > *nallocp) {
|
|
free(*fdrp);
|
|
free(*fdwp);
|
|
*fdrp = xmalloc(sz);
|
|
*fdwp = xmalloc(sz);
|
|
*nallocp = sz;
|
|
}
|
|
if (n < *fdl)
|
|
debug("XXX shrink: %d < %d", n, *fdl);
|
|
*fdl = n;
|
|
memset(*fdrp, 0, sz);
|
|
memset(*fdwp, 0, sz);
|
|
|
|
for (i = 0; i < sockets_alloc; i++) {
|
|
switch (sockets[i].type) {
|
|
case AUTH_SOCKET:
|
|
case AUTH_CONNECTION:
|
|
FD_SET(sockets[i].fd, *fdrp);
|
|
if (sshbuf_len(sockets[i].output) > 0)
|
|
FD_SET(sockets[i].fd, *fdwp);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
deadline = reaper();
|
|
if (parent_alive_interval != 0)
|
|
deadline = (deadline == 0) ? parent_alive_interval :
|
|
MIN(deadline, parent_alive_interval);
|
|
if (deadline == 0) {
|
|
*tvpp = NULL;
|
|
} else {
|
|
tv.tv_sec = deadline;
|
|
tv.tv_usec = 0;
|
|
*tvpp = &tv;
|
|
}
|
|
return (1);
|
|
}
|
|
|
|
static void
|
|
after_select(fd_set *readset, fd_set *writeset)
|
|
{
|
|
struct sockaddr_un sunaddr;
|
|
socklen_t slen;
|
|
char buf[1024];
|
|
int len, sock, r;
|
|
u_int i, orig_alloc;
|
|
uid_t euid;
|
|
gid_t egid;
|
|
|
|
for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++)
|
|
switch (sockets[i].type) {
|
|
case AUTH_UNUSED:
|
|
break;
|
|
case AUTH_SOCKET:
|
|
if (FD_ISSET(sockets[i].fd, readset)) {
|
|
slen = sizeof(sunaddr);
|
|
sock = accept(sockets[i].fd,
|
|
(struct sockaddr *)&sunaddr, &slen);
|
|
if (sock < 0) {
|
|
error("accept from AUTH_SOCKET: %s",
|
|
strerror(errno));
|
|
break;
|
|
}
|
|
if (getpeereid(sock, &euid, &egid) < 0) {
|
|
error("getpeereid %d failed: %s",
|
|
sock, strerror(errno));
|
|
close(sock);
|
|
break;
|
|
}
|
|
if ((euid != 0) && (getuid() != euid)) {
|
|
error("uid mismatch: "
|
|
"peer euid %u != uid %u",
|
|
(u_int) euid, (u_int) getuid());
|
|
close(sock);
|
|
break;
|
|
}
|
|
new_socket(AUTH_CONNECTION, sock);
|
|
}
|
|
break;
|
|
case AUTH_CONNECTION:
|
|
if (sshbuf_len(sockets[i].output) > 0 &&
|
|
FD_ISSET(sockets[i].fd, writeset)) {
|
|
len = write(sockets[i].fd,
|
|
sshbuf_ptr(sockets[i].output),
|
|
sshbuf_len(sockets[i].output));
|
|
if (len == -1 && (errno == EAGAIN ||
|
|
errno == EWOULDBLOCK ||
|
|
errno == EINTR))
|
|
continue;
|
|
if (len <= 0) {
|
|
close_socket(&sockets[i]);
|
|
break;
|
|
}
|
|
if ((r = sshbuf_consume(sockets[i].output,
|
|
len)) != 0)
|
|
fatal("%s: buffer error: %s",
|
|
__func__, ssh_err(r));
|
|
}
|
|
if (FD_ISSET(sockets[i].fd, readset)) {
|
|
len = read(sockets[i].fd, buf, sizeof(buf));
|
|
if (len == -1 && (errno == EAGAIN ||
|
|
errno == EWOULDBLOCK ||
|
|
errno == EINTR))
|
|
continue;
|
|
if (len <= 0) {
|
|
close_socket(&sockets[i]);
|
|
break;
|
|
}
|
|
if ((r = sshbuf_put(sockets[i].input,
|
|
buf, len)) != 0)
|
|
fatal("%s: buffer error: %s",
|
|
__func__, ssh_err(r));
|
|
explicit_bzero(buf, sizeof(buf));
|
|
process_message(&sockets[i]);
|
|
}
|
|
break;
|
|
default:
|
|
fatal("Unknown type %d", sockets[i].type);
|
|
}
|
|
}
|
|
|
|
static void
|
|
cleanup_socket(void)
|
|
{
|
|
if (cleanup_pid != 0 && getpid() != cleanup_pid)
|
|
return;
|
|
debug("%s: cleanup", __func__);
|
|
if (socket_name[0])
|
|
unlink(socket_name);
|
|
if (socket_dir[0])
|
|
rmdir(socket_dir);
|
|
}
|
|
|
|
void
|
|
cleanup_exit(int i)
|
|
{
|
|
cleanup_socket();
|
|
_exit(i);
|
|
}
|
|
|
|
/*ARGSUSED*/
|
|
static void
|
|
cleanup_handler(int sig)
|
|
{
|
|
cleanup_socket();
|
|
#ifdef ENABLE_PKCS11
|
|
pkcs11_terminate();
|
|
#endif
|
|
_exit(2);
|
|
}
|
|
|
|
static void
|
|
check_parent_exists(void)
|
|
{
|
|
/*
|
|
* If our parent has exited then getppid() will return (pid_t)1,
|
|
* so testing for that should be safe.
|
|
*/
|
|
if (parent_pid != -1 && getppid() != parent_pid) {
|
|
/* printf("Parent has died - Authentication agent exiting.\n"); */
|
|
cleanup_socket();
|
|
_exit(2);
|
|
}
|
|
}
|
|
|
|
static void
|
|
usage(void)
|
|
{
|
|
fprintf(stderr,
|
|
"usage: ssh-agent [-c | -s] [-d] [-a bind_address] [-E fingerprint_hash]\n"
|
|
" [-t life] [command [arg ...]]\n"
|
|
" ssh-agent [-c | -s] -k\n");
|
|
fprintf(stderr, " -x Exit when the last client disconnects.\n");
|
|
exit(1);
|
|
}
|
|
|
|
int
|
|
main(int ac, char **av)
|
|
{
|
|
int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0;
|
|
int sock, fd, ch, result, saved_errno;
|
|
u_int nalloc;
|
|
char *shell, *format, *pidstr, *agentsocket = NULL;
|
|
fd_set *readsetp = NULL, *writesetp = NULL;
|
|
#ifdef HAVE_SETRLIMIT
|
|
struct rlimit rlim;
|
|
#endif
|
|
extern int optind;
|
|
extern char *optarg;
|
|
pid_t pid;
|
|
char pidstrbuf[1 + 3 * sizeof pid];
|
|
struct timeval *tvp = NULL;
|
|
size_t len;
|
|
mode_t prev_mask;
|
|
|
|
/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
|
|
sanitise_stdfd();
|
|
|
|
/* drop */
|
|
setegid(getgid());
|
|
setgid(getgid());
|
|
setuid(geteuid());
|
|
|
|
#if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE)
|
|
/* Disable ptrace on Linux without sgid bit */
|
|
prctl(PR_SET_DUMPABLE, 0);
|
|
#endif
|
|
|
|
#ifdef WITH_OPENSSL
|
|
OpenSSL_add_all_algorithms();
|
|
#endif
|
|
|
|
__progname = ssh_get_progname(av[0]);
|
|
seed_rng();
|
|
|
|
while ((ch = getopt(ac, av, "cdksE:a:t:x")) != -1) {
|
|
switch (ch) {
|
|
case 'E':
|
|
fingerprint_hash = ssh_digest_alg_by_name(optarg);
|
|
if (fingerprint_hash == -1)
|
|
fatal("Invalid hash algorithm \"%s\"", optarg);
|
|
break;
|
|
case 'c':
|
|
if (s_flag)
|
|
usage();
|
|
c_flag++;
|
|
break;
|
|
case 'k':
|
|
k_flag++;
|
|
break;
|
|
case 's':
|
|
if (c_flag)
|
|
usage();
|
|
s_flag++;
|
|
break;
|
|
case 'd':
|
|
if (d_flag)
|
|
usage();
|
|
d_flag++;
|
|
break;
|
|
case 'a':
|
|
agentsocket = optarg;
|
|
break;
|
|
case 't':
|
|
if ((lifetime = convtime(optarg)) == -1) {
|
|
fprintf(stderr, "Invalid lifetime\n");
|
|
usage();
|
|
}
|
|
break;
|
|
case 'x':
|
|
xcount = 0;
|
|
break;
|
|
default:
|
|
usage();
|
|
}
|
|
}
|
|
ac -= optind;
|
|
av += optind;
|
|
|
|
if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
|
|
usage();
|
|
|
|
if (ac == 0 && !c_flag && !s_flag) {
|
|
shell = getenv("SHELL");
|
|
if (shell != NULL && (len = strlen(shell)) > 2 &&
|
|
strncmp(shell + len - 3, "csh", 3) == 0)
|
|
c_flag = 1;
|
|
}
|
|
if (k_flag) {
|
|
const char *errstr = NULL;
|
|
|
|
pidstr = getenv(SSH_AGENTPID_ENV_NAME);
|
|
if (pidstr == NULL) {
|
|
fprintf(stderr, "%s not set, cannot kill agent\n",
|
|
SSH_AGENTPID_ENV_NAME);
|
|
exit(1);
|
|
}
|
|
pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
|
|
if (errstr) {
|
|
fprintf(stderr,
|
|
"%s=\"%s\", which is not a good PID: %s\n",
|
|
SSH_AGENTPID_ENV_NAME, pidstr, errstr);
|
|
exit(1);
|
|
}
|
|
if (kill(pid, SIGTERM) == -1) {
|
|
perror("kill");
|
|
exit(1);
|
|
}
|
|
format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
|
|
printf(format, SSH_AUTHSOCKET_ENV_NAME);
|
|
printf(format, SSH_AGENTPID_ENV_NAME);
|
|
printf("echo Agent pid %ld killed;\n", (long)pid);
|
|
exit(0);
|
|
}
|
|
parent_pid = getpid();
|
|
|
|
if (agentsocket == NULL) {
|
|
/* Create private directory for agent socket */
|
|
mktemp_proto(socket_dir, sizeof(socket_dir));
|
|
if (mkdtemp(socket_dir) == NULL) {
|
|
perror("mkdtemp: private socket dir");
|
|
exit(1);
|
|
}
|
|
snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
|
|
(long)parent_pid);
|
|
} else {
|
|
/* Try to use specified agent socket */
|
|
socket_dir[0] = '\0';
|
|
strlcpy(socket_name, agentsocket, sizeof socket_name);
|
|
}
|
|
|
|
/*
|
|
* Create socket early so it will exist before command gets run from
|
|
* the parent.
|
|
*/
|
|
prev_mask = umask(0177);
|
|
sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0);
|
|
if (sock < 0) {
|
|
/* XXX - unix_listener() calls error() not perror() */
|
|
*socket_name = '\0'; /* Don't unlink any existing file */
|
|
cleanup_exit(1);
|
|
}
|
|
umask(prev_mask);
|
|
|
|
/*
|
|
* Fork, and have the parent execute the command, if any, or present
|
|
* the socket data. The child continues as the authentication agent.
|
|
*/
|
|
if (d_flag) {
|
|
log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
|
|
format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
|
|
printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
|
|
SSH_AUTHSOCKET_ENV_NAME);
|
|
printf("echo Agent pid %ld;\n", (long)parent_pid);
|
|
goto skip;
|
|
}
|
|
pid = fork();
|
|
if (pid == -1) {
|
|
perror("fork");
|
|
cleanup_exit(1);
|
|
}
|
|
if (pid != 0) { /* Parent - execute the given command. */
|
|
close(sock);
|
|
snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
|
|
if (ac == 0) {
|
|
format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
|
|
printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
|
|
SSH_AUTHSOCKET_ENV_NAME);
|
|
printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
|
|
SSH_AGENTPID_ENV_NAME);
|
|
printf("echo Agent pid %ld;\n", (long)pid);
|
|
exit(0);
|
|
}
|
|
if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
|
|
setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
|
|
perror("setenv");
|
|
exit(1);
|
|
}
|
|
execvp(av[0], av);
|
|
perror(av[0]);
|
|
exit(1);
|
|
}
|
|
/* child */
|
|
log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
|
|
|
|
if (setsid() == -1) {
|
|
error("setsid: %s", strerror(errno));
|
|
cleanup_exit(1);
|
|
}
|
|
|
|
(void)chdir("/");
|
|
if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
|
|
/* XXX might close listen socket */
|
|
(void)dup2(fd, STDIN_FILENO);
|
|
(void)dup2(fd, STDOUT_FILENO);
|
|
(void)dup2(fd, STDERR_FILENO);
|
|
if (fd > 2)
|
|
close(fd);
|
|
}
|
|
|
|
#ifdef HAVE_SETRLIMIT
|
|
/* deny core dumps, since memory contains unencrypted private keys */
|
|
rlim.rlim_cur = rlim.rlim_max = 0;
|
|
if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
|
|
error("setrlimit RLIMIT_CORE: %s", strerror(errno));
|
|
cleanup_exit(1);
|
|
}
|
|
#endif
|
|
|
|
skip:
|
|
|
|
cleanup_pid = getpid();
|
|
|
|
#ifdef ENABLE_PKCS11
|
|
pkcs11_init(0);
|
|
#endif
|
|
new_socket(AUTH_SOCKET, sock);
|
|
if (ac > 0)
|
|
parent_alive_interval = 10;
|
|
idtab_init();
|
|
signal(SIGPIPE, SIG_IGN);
|
|
signal(SIGINT, d_flag ? cleanup_handler : SIG_IGN);
|
|
signal(SIGHUP, cleanup_handler);
|
|
signal(SIGTERM, cleanup_handler);
|
|
nalloc = 0;
|
|
|
|
while (1) {
|
|
prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp);
|
|
result = select(max_fd + 1, readsetp, writesetp, NULL, tvp);
|
|
saved_errno = errno;
|
|
if (parent_alive_interval != 0)
|
|
check_parent_exists();
|
|
(void) reaper(); /* remove expired keys */
|
|
if (result < 0) {
|
|
if (saved_errno == EINTR)
|
|
continue;
|
|
fatal("select: %s", strerror(saved_errno));
|
|
} else if (result > 0)
|
|
after_select(readsetp, writesetp);
|
|
}
|
|
/* NOTREACHED */
|
|
}
|