openssh/ssh-add.c

1054 lines
27 KiB
C

/* $OpenBSD: ssh-add.c,v 1.169 2023/12/18 14:46:56 djm 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 "includes.h"
#include <sys/types.h>
#include <sys/stat.h>
#ifdef WITH_OPENSSL
# include <openssl/evp.h>
# include "openbsd-compat/openssl-compat.h"
#endif
#include <errno.h>
#include <fcntl.h>
#include <pwd.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>
#include "xmalloc.h"
#include "ssh.h"
#include "log.h"
#include "sshkey.h"
#include "sshbuf.h"
#include "authfd.h"
#include "authfile.h"
#include "pathnames.h"
#include "misc.h"
#include "ssherr.h"
#include "digest.h"
#include "ssh-sk.h"
#include "sk-api.h"
#include "hostfile.h"
/* argv0 */
extern char *__progname;
/* Default files to add */
static char *default_files[] = {
#ifdef WITH_OPENSSL
_PATH_SSH_CLIENT_ID_RSA,
#ifdef OPENSSL_HAS_ECC
_PATH_SSH_CLIENT_ID_ECDSA,
_PATH_SSH_CLIENT_ID_ECDSA_SK,
#endif
#endif /* WITH_OPENSSL */
_PATH_SSH_CLIENT_ID_ED25519,
_PATH_SSH_CLIENT_ID_ED25519_SK,
_PATH_SSH_CLIENT_ID_XMSS,
_PATH_SSH_CLIENT_ID_DSA,
NULL
};
static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
/* Default lifetime (0 == forever) */
static int lifetime = 0;
/* User has to confirm key use */
static int confirm = 0;
/* Maximum number of signatures (XMSS) */
static u_int maxsign = 0;
static u_int minleft = 0;
/* we keep a cache of one passphrase */
static char *pass = NULL;
static void
clear_pass(void)
{
if (pass) {
freezero(pass, strlen(pass));
pass = NULL;
}
}
static int
delete_one(int agent_fd, const struct sshkey *key, const char *comment,
const char *path, int qflag)
{
int r;
if ((r = ssh_remove_identity(agent_fd, key)) != 0) {
fprintf(stderr, "Could not remove identity \"%s\": %s\n",
path, ssh_err(r));
return r;
}
if (!qflag) {
fprintf(stderr, "Identity removed: %s %s (%s)\n", path,
sshkey_type(key), comment ? comment : "no comment");
}
return 0;
}
static int
delete_stdin(int agent_fd, int qflag, int key_only, int cert_only)
{
char *line = NULL, *cp;
size_t linesize = 0;
struct sshkey *key = NULL;
int lnum = 0, r, ret = -1;
while (getline(&line, &linesize, stdin) != -1) {
lnum++;
sshkey_free(key);
key = NULL;
line[strcspn(line, "\n")] = '\0';
cp = line + strspn(line, " \t");
if (*cp == '#' || *cp == '\0')
continue;
if ((key = sshkey_new(KEY_UNSPEC)) == NULL)
fatal_f("sshkey_new");
if ((r = sshkey_read(key, &cp)) != 0) {
error_r(r, "(stdin):%d: invalid key", lnum);
continue;
}
if ((!key_only && !cert_only) ||
(key_only && !sshkey_is_cert(key)) ||
(cert_only && sshkey_is_cert(key))) {
if (delete_one(agent_fd, key, cp,
"(stdin)", qflag) == 0)
ret = 0;
}
}
sshkey_free(key);
free(line);
return ret;
}
static int
delete_file(int agent_fd, const char *filename, int key_only,
int cert_only, int qflag)
{
struct sshkey *public, *cert = NULL;
char *certpath = NULL, *comment = NULL;
int r, ret = -1;
if (strcmp(filename, "-") == 0)
return delete_stdin(agent_fd, qflag, key_only, cert_only);
if ((r = sshkey_load_public(filename, &public, &comment)) != 0) {
printf("Bad key file %s: %s\n", filename, ssh_err(r));
return -1;
}
if ((!key_only && !cert_only) ||
(key_only && !sshkey_is_cert(public)) ||
(cert_only && sshkey_is_cert(public))) {
if (delete_one(agent_fd, public, comment, filename, qflag) == 0)
ret = 0;
}
if (key_only)
goto out;
/* Now try to delete the corresponding certificate too */
free(comment);
comment = NULL;
xasprintf(&certpath, "%s-cert.pub", filename);
if ((r = sshkey_load_public(certpath, &cert, &comment)) != 0) {
if (r != SSH_ERR_SYSTEM_ERROR || errno != ENOENT)
error_r(r, "Failed to load certificate \"%s\"", certpath);
goto out;
}
if (!sshkey_equal_public(cert, public))
fatal("Certificate %s does not match private key %s",
certpath, filename);
if (delete_one(agent_fd, cert, comment, certpath, qflag) == 0)
ret = 0;
out:
sshkey_free(cert);
sshkey_free(public);
free(certpath);
free(comment);
return ret;
}
/* Send a request to remove all identities. */
static int
delete_all(int agent_fd, int qflag)
{
int ret = -1;
/*
* Since the agent might be forwarded, old or non-OpenSSH, when asked
* to remove all keys, attempt to remove both protocol v.1 and v.2
* keys.
*/
if (ssh_remove_all_identities(agent_fd, 2) == 0)
ret = 0;
/* ignore error-code for ssh1 */
ssh_remove_all_identities(agent_fd, 1);
if (ret != 0)
fprintf(stderr, "Failed to remove all identities.\n");
else if (!qflag)
fprintf(stderr, "All identities removed.\n");
return ret;
}
static int
add_file(int agent_fd, const char *filename, int key_only, int cert_only,
int qflag, const char *skprovider,
struct dest_constraint **dest_constraints,
size_t ndest_constraints)
{
struct sshkey *private, *cert;
char *comment = NULL;
char msg[1024], *certpath = NULL;
int r, fd, ret = -1;
size_t i;
u_int32_t left;
struct sshbuf *keyblob;
struct ssh_identitylist *idlist;
if (strcmp(filename, "-") == 0) {
fd = STDIN_FILENO;
filename = "(stdin)";
} else if ((fd = open(filename, O_RDONLY)) == -1) {
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.
*/
if (fd != STDIN_FILENO) {
if (sshkey_perm_ok(fd, filename) != 0) {
close(fd);
return -1;
}
}
if ((r = sshbuf_load_fd(fd, &keyblob)) != 0) {
fprintf(stderr, "Error loading key \"%s\": %s\n",
filename, ssh_err(r));
sshbuf_free(keyblob);
close(fd);
return -1;
}
close(fd);
/* At first, try empty passphrase */
if ((r = sshkey_parse_private_fileblob(keyblob, "", &private,
&comment)) != 0 && r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
fprintf(stderr, "Error loading key \"%s\": %s\n",
filename, ssh_err(r));
goto fail_load;
}
/* try last */
if (private == NULL && pass != NULL) {
if ((r = sshkey_parse_private_fileblob(keyblob, pass, &private,
&comment)) != 0 && r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
fprintf(stderr, "Error loading key \"%s\": %s\n",
filename, ssh_err(r));
goto fail_load;
}
}
if (private == NULL) {
/* clear passphrase since it did not work */
clear_pass();
snprintf(msg, sizeof msg, "Enter passphrase for %s%s: ",
filename, confirm ? " (will confirm each use)" : "");
for (;;) {
pass = read_passphrase(msg, RP_ALLOW_STDIN);
if (strcmp(pass, "") == 0)
goto fail_load;
if ((r = sshkey_parse_private_fileblob(keyblob, pass,
&private, &comment)) == 0)
break;
else if (r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
fprintf(stderr,
"Error loading key \"%s\": %s\n",
filename, ssh_err(r));
fail_load:
clear_pass();
sshbuf_free(keyblob);
return -1;
}
clear_pass();
snprintf(msg, sizeof msg,
"Bad passphrase, try again for %s%s: ", filename,
confirm ? " (will confirm each use)" : "");
}
}
if (comment == NULL || *comment == '\0')
comment = xstrdup(filename);
sshbuf_free(keyblob);
/* For XMSS */
if ((r = sshkey_set_filename(private, filename)) != 0) {
fprintf(stderr, "Could not add filename to private key: %s (%s)\n",
filename, comment);
goto out;
}
if (maxsign && minleft &&
(r = ssh_fetch_identitylist(agent_fd, &idlist)) == 0) {
for (i = 0; i < idlist->nkeys; i++) {
if (!sshkey_equal_public(idlist->keys[i], private))
continue;
left = sshkey_signatures_left(idlist->keys[i]);
if (left < minleft) {
fprintf(stderr,
"Only %d signatures left.\n", left);
break;
}
fprintf(stderr, "Skipping update: ");
if (left == minleft) {
fprintf(stderr,
"required signatures left (%d).\n", left);
} else {
fprintf(stderr,
"more signatures left (%d) than"
" required (%d).\n", left, minleft);
}
ssh_free_identitylist(idlist);
goto out;
}
ssh_free_identitylist(idlist);
}
if (sshkey_is_sk(private)) {
if (skprovider == NULL) {
fprintf(stderr, "Cannot load FIDO key %s "
"without provider\n", filename);
goto out;
}
} else {
/* Don't send provider constraint for other keys */
skprovider = NULL;
}
if (!cert_only &&
(r = ssh_add_identity_constrained(agent_fd, private, comment,
lifetime, confirm, maxsign, skprovider,
dest_constraints, ndest_constraints)) == 0) {
ret = 0;
if (!qflag) {
fprintf(stderr, "Identity added: %s (%s)\n",
filename, comment);
if (lifetime != 0) {
fprintf(stderr,
"Lifetime set to %d seconds\n", lifetime);
}
if (confirm != 0) {
fprintf(stderr, "The user must confirm "
"each use of the key\n");
}
}
} else {
fprintf(stderr, "Could not add identity \"%s\": %s\n",
filename, ssh_err(r));
}
/* Skip trying to load the cert if requested */
if (key_only)
goto out;
/* Now try to add the certificate flavour too */
xasprintf(&certpath, "%s-cert.pub", filename);
if ((r = sshkey_load_public(certpath, &cert, NULL)) != 0) {
if (r != SSH_ERR_SYSTEM_ERROR || errno != ENOENT)
error_r(r, "Failed to load certificate \"%s\"",
certpath);
goto out;
}
if (!sshkey_equal_public(cert, private)) {
error("Certificate %s does not match private key %s",
certpath, filename);
sshkey_free(cert);
goto out;
}
/* Graft with private bits */
if ((r = sshkey_to_certified(private)) != 0) {
error_fr(r, "sshkey_to_certified");
sshkey_free(cert);
goto out;
}
if ((r = sshkey_cert_copy(cert, private)) != 0) {
error_fr(r, "sshkey_cert_copy");
sshkey_free(cert);
goto out;
}
sshkey_free(cert);
if ((r = ssh_add_identity_constrained(agent_fd, private, comment,
lifetime, confirm, maxsign, skprovider,
dest_constraints, ndest_constraints)) != 0) {
error_r(r, "Certificate %s (%s) add failed", certpath,
private->cert->key_id);
goto out;
}
/* success */
if (!qflag) {
fprintf(stderr, "Certificate added: %s (%s)\n", certpath,
private->cert->key_id);
if (lifetime != 0) {
fprintf(stderr, "Lifetime set to %d seconds\n",
lifetime);
}
if (confirm != 0) {
fprintf(stderr, "The user must confirm each use "
"of the key\n");
}
}
out:
free(certpath);
free(comment);
sshkey_free(private);
return ret;
}
static int
update_card(int agent_fd, int add, const char *id, int qflag,
int key_only, int cert_only,
struct dest_constraint **dest_constraints, size_t ndest_constraints,
struct sshkey **certs, size_t ncerts)
{
char *pin = NULL;
int r, ret = -1;
if (key_only)
ncerts = 0;
if (add) {
if ((pin = read_passphrase("Enter passphrase for PKCS#11: ",
RP_ALLOW_STDIN)) == NULL)
return -1;
}
if ((r = ssh_update_card(agent_fd, add, id, pin == NULL ? "" : pin,
lifetime, confirm, dest_constraints, ndest_constraints,
cert_only, certs, ncerts)) == 0) {
ret = 0;
if (!qflag) {
fprintf(stderr, "Card %s: %s\n",
add ? "added" : "removed", id);
}
} else {
fprintf(stderr, "Could not %s card \"%s\": %s\n",
add ? "add" : "remove", id, ssh_err(r));
ret = -1;
}
free(pin);
return ret;
}
static int
test_key(int agent_fd, const char *filename)
{
struct sshkey *key = NULL;
u_char *sig = NULL;
const char *alg = NULL;
size_t slen = 0;
int r, ret = -1;
char data[1024];
if ((r = sshkey_load_public(filename, &key, NULL)) != 0) {
error_r(r, "Couldn't read public key %s", filename);
return -1;
}
if (sshkey_type_plain(key->type) == KEY_RSA)
alg = "rsa-sha2-256";
arc4random_buf(data, sizeof(data));
if ((r = ssh_agent_sign(agent_fd, key, &sig, &slen, data, sizeof(data),
alg, 0)) != 0) {
error_r(r, "Agent signature failed for %s", filename);
goto done;
}
if ((r = sshkey_verify(key, sig, slen, data, sizeof(data),
alg, 0, NULL)) != 0) {
error_r(r, "Signature verification failed for %s", filename);
goto done;
}
/* success */
ret = 0;
done:
free(sig);
sshkey_free(key);
return ret;
}
static int
list_identities(int agent_fd, int do_fp)
{
char *fp;
int r;
struct ssh_identitylist *idlist;
u_int32_t left;
size_t i;
if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
if (r != SSH_ERR_AGENT_NO_IDENTITIES)
fprintf(stderr, "error fetching identities: %s\n",
ssh_err(r));
else
printf("The agent has no identities.\n");
return -1;
}
for (i = 0; i < idlist->nkeys; i++) {
if (do_fp) {
fp = sshkey_fingerprint(idlist->keys[i],
fingerprint_hash, SSH_FP_DEFAULT);
printf("%u %s %s (%s)\n", sshkey_size(idlist->keys[i]),
fp == NULL ? "(null)" : fp, idlist->comments[i],
sshkey_type(idlist->keys[i]));
free(fp);
} else {
if ((r = sshkey_write(idlist->keys[i], stdout)) != 0) {
fprintf(stderr, "sshkey_write: %s\n",
ssh_err(r));
continue;
}
fprintf(stdout, " %s", idlist->comments[i]);
left = sshkey_signatures_left(idlist->keys[i]);
if (left > 0)
fprintf(stdout,
" [signatures left %d]", left);
fprintf(stdout, "\n");
}
}
ssh_free_identitylist(idlist);
return 0;
}
static int
lock_agent(int agent_fd, int lock)
{
char prompt[100], *p1, *p2;
int r, 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;
}
freezero(p2, strlen(p2));
}
if (passok) {
if ((r = ssh_lock_agent(agent_fd, lock, p1)) == 0) {
fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un");
ret = 0;
} else {
fprintf(stderr, "Failed to %slock agent: %s\n",
lock ? "" : "un", ssh_err(r));
}
}
freezero(p1, strlen(p1));
return (ret);
}
static int
load_resident_keys(int agent_fd, const char *skprovider, int qflag,
struct dest_constraint **dest_constraints, size_t ndest_constraints)
{
struct sshsk_resident_key **srks;
size_t nsrks, i;
struct sshkey *key;
int r, ok = 0;
char *fp;
pass = read_passphrase("Enter PIN for authenticator: ", RP_ALLOW_STDIN);
if ((r = sshsk_load_resident(skprovider, NULL, pass, 0,
&srks, &nsrks)) != 0) {
error_r(r, "Unable to load resident keys");
return r;
}
for (i = 0; i < nsrks; i++) {
key = srks[i]->key;
if ((fp = sshkey_fingerprint(key,
fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
fatal_f("sshkey_fingerprint failed");
if ((r = ssh_add_identity_constrained(agent_fd, key, "",
lifetime, confirm, maxsign, skprovider,
dest_constraints, ndest_constraints)) != 0) {
error("Unable to add key %s %s",
sshkey_type(key), fp);
free(fp);
ok = r;
continue;
}
if (ok == 0)
ok = 1;
if (!qflag) {
fprintf(stderr, "Resident identity added: %s %s\n",
sshkey_type(key), fp);
if (lifetime != 0) {
fprintf(stderr,
"Lifetime set to %d seconds\n", lifetime);
}
if (confirm != 0) {
fprintf(stderr, "The user must confirm "
"each use of the key\n");
}
}
free(fp);
}
sshsk_free_resident_keys(srks, nsrks);
if (nsrks == 0)
return SSH_ERR_KEY_NOT_FOUND;
return ok == 1 ? 0 : ok;
}
static int
do_file(int agent_fd, int deleting, int key_only, int cert_only,
char *file, int qflag, const char *skprovider,
struct dest_constraint **dest_constraints, size_t ndest_constraints)
{
if (deleting) {
if (delete_file(agent_fd, file, key_only,
cert_only, qflag) == -1)
return -1;
} else {
if (add_file(agent_fd, file, key_only, cert_only, qflag,
skprovider, dest_constraints, ndest_constraints) == -1)
return -1;
}
return 0;
}
/* Append string 's' to a NULL-terminated array of strings */
static void
stringlist_append(char ***listp, const char *s)
{
size_t i = 0;
if (*listp == NULL)
*listp = xcalloc(2, sizeof(**listp));
else {
for (i = 0; (*listp)[i] != NULL; i++)
; /* count */
*listp = xrecallocarray(*listp, i + 1, i + 2, sizeof(**listp));
}
(*listp)[i] = xstrdup(s);
}
static void
parse_dest_constraint_hop(const char *s, struct dest_constraint_hop *dch,
char **hostkey_files)
{
char *user = NULL, *host, *os, *path;
size_t i;
struct hostkeys *hostkeys;
const struct hostkey_entry *hke;
int r, want_ca;
memset(dch, '\0', sizeof(*dch));
os = xstrdup(s);
if ((host = strchr(os, '@')) == NULL)
host = os;
else {
*host++ = '\0';
user = os;
}
cleanhostname(host);
/* Trivial case: username@ (all hosts) */
if (*host == '\0') {
if (user == NULL) {
fatal("Invalid key destination constraint \"%s\": "
"does not specify user or host", s);
}
dch->user = xstrdup(user);
/* other fields left blank */
free(os);
return;
}
if (hostkey_files == NULL)
fatal_f("no hostkey files");
/* Otherwise we need to look up the keys for this hostname */
hostkeys = init_hostkeys();
for (i = 0; hostkey_files[i]; i++) {
path = tilde_expand_filename(hostkey_files[i], getuid());
debug2_f("looking up host keys for \"%s\" in %s", host, path);
load_hostkeys(hostkeys, host, path, 0);
free(path);
}
dch->user = user == NULL ? NULL : xstrdup(user);
dch->hostname = xstrdup(host);
for (i = 0; i < hostkeys->num_entries; i++) {
hke = hostkeys->entries + i;
want_ca = hke->marker == MRK_CA;
if (hke->marker != MRK_NONE && !want_ca)
continue;
debug3_f("%s%s%s: adding %s %skey from %s:%lu as key %u",
user == NULL ? "": user, user == NULL ? "" : "@",
host, sshkey_type(hke->key), want_ca ? "CA " : "",
hke->file, hke->line, dch->nkeys);
dch->keys = xrecallocarray(dch->keys, dch->nkeys,
dch->nkeys + 1, sizeof(*dch->keys));
dch->key_is_ca = xrecallocarray(dch->key_is_ca, dch->nkeys,
dch->nkeys + 1, sizeof(*dch->key_is_ca));
if ((r = sshkey_from_private(hke->key,
&(dch->keys[dch->nkeys]))) != 0)
fatal_fr(r, "sshkey_from_private");
dch->key_is_ca[dch->nkeys] = want_ca;
dch->nkeys++;
}
if (dch->nkeys == 0)
fatal("No host keys found for destination \"%s\"", host);
free_hostkeys(hostkeys);
free(os);
return;
}
static void
parse_dest_constraint(const char *s, struct dest_constraint ***dcp,
size_t *ndcp, char **hostkey_files)
{
struct dest_constraint *dc;
char *os, *cp;
dc = xcalloc(1, sizeof(*dc));
os = xstrdup(s);
if ((cp = strchr(os, '>')) == NULL) {
/* initial hop; no 'from' hop specified */
parse_dest_constraint_hop(os, &dc->to, hostkey_files);
} else {
/* two hops specified */
*(cp++) = '\0';
parse_dest_constraint_hop(os, &dc->from, hostkey_files);
parse_dest_constraint_hop(cp, &dc->to, hostkey_files);
if (dc->from.user != NULL) {
fatal("Invalid key constraint %s: cannot specify "
"user on 'from' host", os);
}
}
/* XXX eliminate or error on duplicates */
debug2_f("constraint %zu: %s%s%s (%u keys) > %s%s%s (%u keys)", *ndcp,
dc->from.user ? dc->from.user : "", dc->from.user ? "@" : "",
dc->from.hostname ? dc->from.hostname : "(ORIGIN)", dc->from.nkeys,
dc->to.user ? dc->to.user : "", dc->to.user ? "@" : "",
dc->to.hostname ? dc->to.hostname : "(ANY)", dc->to.nkeys);
*dcp = xrecallocarray(*dcp, *ndcp, *ndcp + 1, sizeof(**dcp));
(*dcp)[(*ndcp)++] = dc;
free(os);
}
static void
usage(void)
{
fprintf(stderr,
"usage: ssh-add [-cDdKkLlqvXx] [-E fingerprint_hash] [-H hostkey_file]\n"
" [-h destination_constraint] [-S provider] [-t life]\n"
#ifdef WITH_XMSS
" [-M maxsign] [-m minleft]\n"
#endif
" [file ...]\n"
" ssh-add -s pkcs11\n"
" ssh-add -e pkcs11\n"
" ssh-add -T pubkey ...\n"
);
}
int
main(int argc, char **argv)
{
extern char *optarg;
extern int optind;
int agent_fd;
char *pkcs11provider = NULL, *skprovider = NULL;
char **dest_constraint_strings = NULL, **hostkey_files = NULL;
int r, i, ch, deleting = 0, ret = 0, key_only = 0, cert_only = 0;
int do_download = 0, xflag = 0, lflag = 0, Dflag = 0;
int qflag = 0, Tflag = 0;
SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
LogLevel log_level = SYSLOG_LEVEL_INFO;
struct sshkey *k, **certs = NULL;
struct dest_constraint **dest_constraints = NULL;
size_t ndest_constraints = 0i, ncerts = 0;
/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
sanitise_stdfd();
__progname = ssh_get_progname(argv[0]);
seed_rng();
log_init(__progname, log_level, log_facility, 1);
setvbuf(stdout, NULL, _IOLBF, 0);
/* First, get a connection to the authentication agent. */
switch (r = ssh_get_authentication_socket(&agent_fd)) {
case 0:
break;
case SSH_ERR_AGENT_NOT_PRESENT:
fprintf(stderr, "Could not open a connection to your "
"authentication agent.\n");
exit(2);
default:
fprintf(stderr, "Error connecting to agent: %s\n", ssh_err(r));
exit(2);
}
skprovider = getenv("SSH_SK_PROVIDER");
while ((ch = getopt(argc, argv, "vkKlLCcdDTxXE:e:h:H:M:m:qs:S:t:")) != -1) {
switch (ch) {
case 'v':
if (log_level == SYSLOG_LEVEL_INFO)
log_level = SYSLOG_LEVEL_DEBUG1;
else if (log_level < SYSLOG_LEVEL_DEBUG3)
log_level++;
break;
case 'E':
fingerprint_hash = ssh_digest_alg_by_name(optarg);
if (fingerprint_hash == -1)
fatal("Invalid hash algorithm \"%s\"", optarg);
break;
case 'H':
stringlist_append(&hostkey_files, optarg);
break;
case 'h':
stringlist_append(&dest_constraint_strings, optarg);
break;
case 'k':
key_only = 1;
break;
case 'C':
cert_only = 1;
break;
case 'K':
do_download = 1;
break;
case 'l':
case 'L':
if (lflag != 0)
fatal("-%c flag already specified", lflag);
lflag = ch;
break;
case 'x':
case 'X':
if (xflag != 0)
fatal("-%c flag already specified", xflag);
xflag = ch;
break;
case 'c':
confirm = 1;
break;
case 'm':
minleft = (u_int)strtonum(optarg, 1, UINT_MAX, NULL);
if (minleft == 0) {
usage();
ret = 1;
goto done;
}
break;
case 'M':
maxsign = (u_int)strtonum(optarg, 1, UINT_MAX, NULL);
if (maxsign == 0) {
usage();
ret = 1;
goto done;
}
break;
case 'd':
deleting = 1;
break;
case 'D':
Dflag = 1;
break;
case 's':
pkcs11provider = optarg;
break;
case 'S':
skprovider = optarg;
break;
case 'e':
deleting = 1;
pkcs11provider = optarg;
break;
case 't':
if ((lifetime = convtime(optarg)) == -1 ||
lifetime < 0 || (u_long)lifetime > UINT32_MAX) {
fprintf(stderr, "Invalid lifetime\n");
ret = 1;
goto done;
}
break;
case 'q':
qflag = 1;
break;
case 'T':
Tflag = 1;
break;
default:
usage();
ret = 1;
goto done;
}
}
log_init(__progname, log_level, log_facility, 1);
if ((xflag != 0) + (lflag != 0) + (Dflag != 0) > 1)
fatal("Invalid combination of actions");
else if (xflag) {
if (lock_agent(agent_fd, xflag == 'x' ? 1 : 0) == -1)
ret = 1;
goto done;
} else if (lflag) {
if (list_identities(agent_fd, lflag == 'l' ? 1 : 0) == -1)
ret = 1;
goto done;
} else if (Dflag) {
if (delete_all(agent_fd, qflag) == -1)
ret = 1;
goto done;
}
#ifdef ENABLE_SK_INTERNAL
if (skprovider == NULL)
skprovider = "internal";
#endif
if (hostkey_files == NULL) {
/* use defaults from readconf.c */
stringlist_append(&hostkey_files, _PATH_SSH_USER_HOSTFILE);
stringlist_append(&hostkey_files, _PATH_SSH_USER_HOSTFILE2);
stringlist_append(&hostkey_files, _PATH_SSH_SYSTEM_HOSTFILE);
stringlist_append(&hostkey_files, _PATH_SSH_SYSTEM_HOSTFILE2);
}
if (dest_constraint_strings != NULL) {
for (i = 0; dest_constraint_strings[i] != NULL; i++) {
parse_dest_constraint(dest_constraint_strings[i],
&dest_constraints, &ndest_constraints, hostkey_files);
}
}
argc -= optind;
argv += optind;
if (Tflag) {
if (argc <= 0)
fatal("no keys to test");
for (r = i = 0; i < argc; i++)
r |= test_key(agent_fd, argv[i]);
ret = r == 0 ? 0 : 1;
goto done;
}
if (pkcs11provider != NULL) {
for (i = 0; i < argc; i++) {
if ((r = sshkey_load_public(argv[i], &k, NULL)) != 0)
fatal_fr(r, "load certificate %s", argv[i]);
certs = xrecallocarray(certs, ncerts, ncerts + 1,
sizeof(*certs));
debug2("%s: %s", argv[i], sshkey_ssh_name(k));
certs[ncerts++] = k;
}
debug2_f("loaded %zu certificates", ncerts);
if (update_card(agent_fd, !deleting, pkcs11provider,
qflag, key_only, cert_only,
dest_constraints, ndest_constraints,
certs, ncerts) == -1)
ret = 1;
goto done;
}
if (do_download) {
if (skprovider == NULL)
fatal("Cannot download keys without provider");
if (load_resident_keys(agent_fd, skprovider, qflag,
dest_constraints, ndest_constraints) != 0)
ret = 1;
goto done;
}
if (argc == 0) {
char buf[PATH_MAX];
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) == -1)
continue;
if (do_file(agent_fd, deleting, key_only, cert_only,
buf, qflag, skprovider,
dest_constraints, ndest_constraints) == -1)
ret = 1;
else
count++;
}
if (count == 0)
ret = 1;
} else {
for (i = 0; i < argc; i++) {
if (do_file(agent_fd, deleting, key_only, cert_only,
argv[i], qflag, skprovider,
dest_constraints, ndest_constraints) == -1)
ret = 1;
}
}
done:
clear_pass();
ssh_close_authentication_socket(agent_fd);
return ret;
}