OpenBSD-4.6/usr.bin/ssh/ssh-add.c
/* $OpenBSD: ssh-add.c,v 1.90 2007/09/09 11:38:01 sobrado Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
* Adds an identity to the authentication server, or removes an identity.
*
* As far as I am concerned, the code I have written for this software
* can be used freely for any purpose. Any derived versions of this
* software must be clearly marked as such, and if the derived work is
* incompatible with the protocol description in the RFC file, it must be
* called by a name other than "ssh" or "Secure Shell".
*
* SSH2 implementation,
* Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <openssl/evp.h>
#include <fcntl.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "xmalloc.h"
#include "ssh.h"
#include "rsa.h"
#include "log.h"
#include "key.h"
#include "buffer.h"
#include "authfd.h"
#include "authfile.h"
#include "pathnames.h"
#include "misc.h"
/* argv0 */
extern char *__progname;
/* Default files to add */
static char *default_files[] = {
_PATH_SSH_CLIENT_ID_RSA,
_PATH_SSH_CLIENT_ID_DSA,
_PATH_SSH_CLIENT_IDENTITY,
NULL
};
/* Default lifetime (0 == forever) */
static int lifetime = 0;
/* User has to confirm key use */
static int confirm = 0;
/* we keep a cache of one passphrases */
static char *pass = NULL;
static void
clear_pass(void)
{
if (pass) {
memset(pass, 0, strlen(pass));
xfree(pass);
pass = NULL;
}
}
static int
delete_file(AuthenticationConnection *ac, const char *filename)
{
Key *public;
char *comment = NULL;
int ret = -1;
public = key_load_public(filename, &comment);
if (public == NULL) {
printf("Bad key file %s\n", filename);
return -1;
}
if (ssh_remove_identity(ac, public)) {
fprintf(stderr, "Identity removed: %s (%s)\n", filename, comment);
ret = 0;
} else
fprintf(stderr, "Could not remove identity: %s\n", filename);
key_free(public);
xfree(comment);
return ret;
}
/* Send a request to remove all identities. */
static int
delete_all(AuthenticationConnection *ac)
{
int ret = -1;
if (ssh_remove_all_identities(ac, 1))
ret = 0;
/* ignore error-code for ssh2 */
ssh_remove_all_identities(ac, 2);
if (ret == 0)
fprintf(stderr, "All identities removed.\n");
else
fprintf(stderr, "Failed to remove all identities.\n");
return ret;
}
static int
add_file(AuthenticationConnection *ac, const char *filename)
{
Key *private;
char *comment = NULL;
char msg[1024];
int fd, perms_ok, ret = -1;
if ((fd = open(filename, O_RDONLY)) < 0) {
perror(filename);
return -1;
}
/*
* Since we'll try to load a keyfile multiple times, permission errors
* will occur multiple times, so check perms first and bail if wrong.
*/
perms_ok = key_perm_ok(fd, filename);
close(fd);
if (!perms_ok)
return -1;
/* At first, try empty passphrase */
private = key_load_private(filename, "", &comment);
if (comment == NULL)
comment = xstrdup(filename);
/* try last */
if (private == NULL && pass != NULL)
private = key_load_private(filename, pass, NULL);
if (private == NULL) {
/* clear passphrase since it did not work */
clear_pass();
snprintf(msg, sizeof msg, "Enter passphrase for %.200s: ",
comment);
for (;;) {
pass = read_passphrase(msg, RP_ALLOW_STDIN);
if (strcmp(pass, "") == 0) {
clear_pass();
xfree(comment);
return -1;
}
private = key_load_private(filename, pass, &comment);
if (private != NULL)
break;
clear_pass();
snprintf(msg, sizeof msg,
"Bad passphrase, try again for %.200s: ", comment);
}
}
if (ssh_add_identity_constrained(ac, private, comment, lifetime,
confirm)) {
fprintf(stderr, "Identity added: %s (%s)\n", filename, comment);
ret = 0;
if (lifetime != 0)
fprintf(stderr,
"Lifetime set to %d seconds\n", lifetime);
if (confirm != 0)
fprintf(stderr,
"The user has to confirm each use of the key\n");
} else if (ssh_add_identity(ac, private, comment)) {
fprintf(stderr, "Identity added: %s (%s)\n", filename, comment);
ret = 0;
} else {
fprintf(stderr, "Could not add identity: %s\n", filename);
}
xfree(comment);
key_free(private);
return ret;
}
static int
update_card(AuthenticationConnection *ac, int add, const char *id)
{
char *pin;
int ret = -1;
pin = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN);
if (pin == NULL)
return -1;
if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) {
fprintf(stderr, "Card %s: %s\n",
add ? "added" : "removed", id);
ret = 0;
} else {
fprintf(stderr, "Could not %s card: %s\n",
add ? "add" : "remove", id);
ret = -1;
}
xfree(pin);
return ret;
}
static int
list_identities(AuthenticationConnection *ac, int do_fp)
{
Key *key;
char *comment, *fp;
int had_identities = 0;
int version;
for (version = 1; version <= 2; version++) {
for (key = ssh_get_first_identity(ac, &comment, version);
key != NULL;
key = ssh_get_next_identity(ac, &comment, version)) {
had_identities = 1;
if (do_fp) {
fp = key_fingerprint(key, SSH_FP_MD5,
SSH_FP_HEX);
printf("%d %s %s (%s)\n",
key_size(key), fp, comment, key_type(key));
xfree(fp);
} else {
if (!key_write(key, stdout))
fprintf(stderr, "key_write failed");
fprintf(stdout, " %s\n", comment);
}
key_free(key);
xfree(comment);
}
}
if (!had_identities) {
printf("The agent has no identities.\n");
return -1;
}
return 0;
}
static int
lock_agent(AuthenticationConnection *ac, int lock)
{
char prompt[100], *p1, *p2;
int passok = 1, ret = -1;
strlcpy(prompt, "Enter lock password: ", sizeof(prompt));
p1 = read_passphrase(prompt, RP_ALLOW_STDIN);
if (lock) {
strlcpy(prompt, "Again: ", sizeof prompt);
p2 = read_passphrase(prompt, RP_ALLOW_STDIN);
if (strcmp(p1, p2) != 0) {
fprintf(stderr, "Passwords do not match.\n");
passok = 0;
}
memset(p2, 0, strlen(p2));
xfree(p2);
}
if (passok && ssh_lock_agent(ac, lock, p1)) {
fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un");
ret = 0;
} else
fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un");
memset(p1, 0, strlen(p1));
xfree(p1);
return (ret);
}
static int
do_file(AuthenticationConnection *ac, int deleting, char *file)
{
if (deleting) {
if (delete_file(ac, file) == -1)
return -1;
} else {
if (add_file(ac, file) == -1)
return -1;
}
return 0;
}
static void
usage(void)
{
fprintf(stderr, "usage: %s [options] [file ...]\n", __progname);
fprintf(stderr, "Options:\n");
fprintf(stderr, " -l List fingerprints of all identities.\n");
fprintf(stderr, " -L List public key parameters of all identities.\n");
fprintf(stderr, " -d Delete identity.\n");
fprintf(stderr, " -D Delete all identities.\n");
fprintf(stderr, " -x Lock agent.\n");
fprintf(stderr, " -X Unlock agent.\n");
fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n");
fprintf(stderr, " -c Require confirmation to sign using identities\n");
#ifdef SMARTCARD
fprintf(stderr, " -s reader Add key in smartcard reader.\n");
fprintf(stderr, " -e reader Remove key in smartcard reader.\n");
#endif
}
int
main(int argc, char **argv)
{
extern char *optarg;
extern int optind;
AuthenticationConnection *ac = NULL;
char *sc_reader_id = NULL;
int i, ch, deleting = 0, ret = 0;
/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
sanitise_stdfd();
SSLeay_add_all_algorithms();
/* At first, get a connection to the authentication agent. */
ac = ssh_get_authentication_connection();
if (ac == NULL) {
fprintf(stderr,
"Could not open a connection to your authentication agent.\n");
exit(2);
}
while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) {
switch (ch) {
case 'l':
case 'L':
if (list_identities(ac, ch == 'l' ? 1 : 0) == -1)
ret = 1;
goto done;
case 'x':
case 'X':
if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1)
ret = 1;
goto done;
case 'c':
confirm = 1;
break;
case 'd':
deleting = 1;
break;
case 'D':
if (delete_all(ac) == -1)
ret = 1;
goto done;
case 's':
sc_reader_id = optarg;
break;
case 'e':
deleting = 1;
sc_reader_id = optarg;
break;
case 't':
if ((lifetime = convtime(optarg)) == -1) {
fprintf(stderr, "Invalid lifetime\n");
ret = 1;
goto done;
}
break;
default:
usage();
ret = 1;
goto done;
}
}
argc -= optind;
argv += optind;
if (sc_reader_id != NULL) {
if (update_card(ac, !deleting, sc_reader_id) == -1)
ret = 1;
goto done;
}
if (argc == 0) {
char buf[MAXPATHLEN];
struct passwd *pw;
struct stat st;
int count = 0;
if ((pw = getpwuid(getuid())) == NULL) {
fprintf(stderr, "No user found with uid %u\n",
(u_int)getuid());
ret = 1;
goto done;
}
for (i = 0; default_files[i]; i++) {
snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir,
default_files[i]);
if (stat(buf, &st) < 0)
continue;
if (do_file(ac, deleting, buf) == -1)
ret = 1;
else
count++;
}
if (count == 0)
ret = 1;
} else {
for (i = 0; i < argc; i++) {
if (do_file(ac, deleting, argv[i]) == -1)
ret = 1;
}
}
clear_pass();
done:
ssh_close_authentication_connection(ac);
return ret;
}