/* print all known host keys for a given host, but skip keys of given type */
static int
show_other_keys(struct hostkeys *hostkeys, struct sshkey *key)
{
int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, KEY_ECDSA, -1};
int i, ret = 0;
char *fp, *ra;
const struct hostkey_entry *found;
for (i = 0; type[i] != -1; i++) {
if (type[i] == key->type)
continue;
if (!lookup_key_in_hostkeys_by_type(hostkeys, type[i], &found))
continue;
fp = sshkey_fingerprint(found->key, SSH_FP_MD5, SSH_FP_HEX);
ra = sshkey_fingerprint(found->key, SSH_FP_MD5,
SSH_FP_RANDOMART);
logit("WARNING: %s key found for host %s\n"
"in %s:%lu\n"
"%s key fingerprint %s.",
sshkey_type(found->key),
found->host, found->file, found->line,
sshkey_type(found->key), fp);
if (options.visual_host_key)
logit("%s", ra);
xfree(ra);
xfree(fp);
ret = 1;
}
return ret;
}
/*
* Formats any key left in authctxt->auth_method_key for inclusion in
* auth_log()'s message. Also includes authxtct->auth_method_info if present.
*/
static char *
format_method_key(Authctxt *authctxt)
{
const struct sshkey *key = authctxt->auth_method_key;
const char *methinfo = authctxt->auth_method_info;
char *fp, *ret = NULL;
if (key == NULL)
return NULL;
if (sshkey_is_cert(key)) {
fp = sshkey_fingerprint(key->cert->signature_key,
options.fingerprint_hash, SSH_FP_DEFAULT);
xasprintf(&ret, "%s ID %s (serial %llu) CA %s %s%s%s",
sshkey_type(key), key->cert->key_id,
(unsigned long long)key->cert->serial,
sshkey_type(key->cert->signature_key),
fp == NULL ? "(null)" : fp,
methinfo == NULL ? "" : ", ",
methinfo == NULL ? "" : methinfo);
free(fp);
} else {
fp = sshkey_fingerprint(key, options.fingerprint_hash,
SSH_FP_DEFAULT);
xasprintf(&ret, "%s %s%s%s", sshkey_type(key),
fp == NULL ? "(null)" : fp,
methinfo == NULL ? "" : ", ",
methinfo == NULL ? "" : methinfo);
free(fp);
}
return ret;
}
/* returns 0 if key verifies or -1 if key does NOT verify */
int
verify_host_key(char *host, struct sockaddr *hostaddr, struct sshkey *host_key)
{
int flags = 0;
char *fp;
fp = sshkey_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
debug("Server host key: %s %s", sshkey_type(host_key), fp);
xfree(fp);
/* XXX certs are not yet supported for DNS */
if (!sshkey_is_cert(host_key) && options.verify_host_key_dns &&
verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) {
if (flags & DNS_VERIFY_FOUND) {
if (options.verify_host_key_dns == 1 &&
flags & DNS_VERIFY_MATCH &&
flags & DNS_VERIFY_SECURE)
return 0;
if (flags & DNS_VERIFY_MATCH) {
matching_host_key_dns = 1;
} else {
warn_changed_key(host_key);
error("Update the SSHFP RR in DNS with the new "
"host key to get rid of this message.");
}
}
}
return check_host_key(host, hostaddr, options.port, host_key, RDRW,
options.user_hostfiles, options.num_user_hostfiles,
options.system_hostfiles, options.num_system_hostfiles);
}
/* Authenticate a certificate key against TrustedUserCAKeys */
static int
user_cert_trusted_ca(struct passwd *pw, Key *key)
{
char *ca_fp, *principals_file = NULL;
const char *reason;
int ret = 0, found_principal = 0, use_authorized_principals;
if (!key_is_cert(key) || options.trusted_user_ca_keys == NULL)
return 0;
if ((ca_fp = sshkey_fingerprint(key->cert->signature_key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
return 0;
if (sshkey_in_file(key->cert->signature_key,
options.trusted_user_ca_keys, 1, 0) != 0) {
debug2("%s: CA %s %s is not listed in %s", __func__,
key_type(key->cert->signature_key), ca_fp,
options.trusted_user_ca_keys);
goto out;
}
/*
* If AuthorizedPrincipals is in use, then compare the certificate
* principals against the names in that file rather than matching
* against the username.
*/
if ((principals_file = authorized_principals_file(pw)) != NULL) {
if (match_principals_file(principals_file, pw, key->cert))
found_principal = 1;
}
/* Try querying command if specified */
if (!found_principal && match_principals_command(pw, key->cert))
found_principal = 1;
/* If principals file or command is specified, then require a match */
use_authorized_principals = principals_file != NULL ||
options.authorized_principals_command != NULL;
if (!found_principal && use_authorized_principals) {
reason = "Certificate does not contain an authorized principal";
fail_reason:
error("%s", reason);
auth_debug_add("%s", reason);
goto out;
}
if (key_cert_check_authority(key, 0, 1,
use_authorized_principals ? NULL : pw->pw_name, &reason) != 0)
goto fail_reason;
if (auth_cert_options(key, pw) != 0)
goto out;
verbose("Accepted certificate ID \"%s\" signed by %s CA %s via %s",
key->cert->key_id, key_type(key->cert->signature_key), ca_fp,
options.trusted_user_ca_keys);
ret = 1;
out:
free(principals_file);
free(ca_fp);
return ret;
}
/* print all known host keys for a given host, but skip keys of given type */
static int
show_other_keys(struct hostkeys *hostkeys, Key *key)
{
int type[] = {
KEY_RSA1,
KEY_RSA,
KEY_DSA,
KEY_ECDSA,
KEY_ED25519,
-1
};
int i, ret = 0;
char *fp, *ra;
const struct hostkey_entry *found;
for (i = 0; type[i] != -1; i++) {
if (type[i] == key->type)
continue;
if (!lookup_key_in_hostkeys_by_type(hostkeys, type[i], &found))
continue;
fp = sshkey_fingerprint(found->key,
options.fingerprint_hash, SSH_FP_DEFAULT);
ra = sshkey_fingerprint(found->key,
options.fingerprint_hash, SSH_FP_RANDOMART);
if (fp == NULL || ra == NULL)
fatal("%s: sshkey_fingerprint fail", __func__);
logit("WARNING: %s key found for host %s\n"
"in %s:%lu\n"
"%s key fingerprint %s.",
key_type(found->key),
found->host, found->file, found->line,
key_type(found->key), fp);
if (options.visual_host_key)
logit("%s", ra);
free(ra);
free(fp);
ret = 1;
}
return ret;
}
void
pubkey_auth_info(Authctxt *authctxt, const Key *key, const char *fmt, ...)
{
char *fp, *extra;
va_list ap;
int i;
extra = NULL;
if (fmt != NULL) {
va_start(ap, fmt);
i = vasprintf(&extra, fmt, ap);
va_end(ap);
if (i < 0 || extra == NULL)
fatal("%s: vasprintf failed", __func__);
}
if (key_is_cert(key)) {
fp = sshkey_fingerprint(key->cert->signature_key,
options.fingerprint_hash, SSH_FP_DEFAULT);
auth_info(authctxt, "%s ID %s (serial %llu) CA %s %s%s%s",
key_type(key), key->cert->key_id,
(unsigned long long)key->cert->serial,
key_type(key->cert->signature_key),
fp == NULL ? "(null)" : fp,
extra == NULL ? "" : ", ", extra == NULL ? "" : extra);
free(fp);
} else {
fp = sshkey_fingerprint(key, options.fingerprint_hash,
SSH_FP_DEFAULT);
auth_info(authctxt, "%s %s%s%s", key_type(key),
fp == NULL ? "(null)" : fp,
extra == NULL ? "" : ", ", extra == NULL ? "" : extra);
free(fp);
}
free(extra);
}
/*
* Performs the RSA authentication dialog with the client. This returns
* 0 if the client could not be authenticated, and 1 if authentication was
* successful. This may exit if there is a serious protocol violation.
*/
int
auth_rsa(Authctxt *authctxt, BIGNUM *client_n)
{
struct ssh *ssh = active_state;
struct sshkey *key;
char *fp;
struct passwd *pw = authctxt->pw;
/* no user given */
if (!authctxt->valid)
return 0;
if (!PRIVSEP(auth_rsa_key_allowed(pw, client_n, &key))) {
auth_clear_options();
return (0);
}
/* Perform the challenge-response dialog for this key. */
if (!auth_rsa_challenge_dialog(key)) {
/* Wrong response. */
verbose("Wrong response to RSA authentication challenge.");
ssh_packet_send_debug(ssh,
"Wrong response to RSA authentication challenge.");
/*
* Break out of the loop. Otherwise we might send
* another challenge and break the protocol.
*/
sshkey_free(key);
return (0);
}
/*
* Correct response. The client has been successfully
* authenticated. Note that we have not yet processed the
* options; this will be reset if the options cause the
* authentication to be rejected.
*/
fp = sshkey_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
verbose("Found matching %s key: %s",
sshkey_type(key), fp);
xfree(fp);
sshkey_free(key);
ssh_packet_send_debug(ssh, "RSA authentication accepted.");
return (1);
}
static void
warn_changed_key(struct sshkey *host_key)
{
char *fp;
fp = sshkey_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
error("It is also possible that a host key has just been changed.");
error("The fingerprint for the %s key sent by the remote host is\n%s.",
sshkey_type(host_key), fp);
error("Please contact your system administrator.");
xfree(fp);
}
/* Checks whether a key has already been previously used for authentication */
int
auth2_key_already_used(Authctxt *authctxt, const struct sshkey *key)
{
u_int i;
char *fp;
for (i = 0; i < authctxt->nprev_keys; i++) {
if (sshkey_equal_public(key, authctxt->prev_keys[i])) {
fp = sshkey_fingerprint(authctxt->prev_keys[i],
options.fingerprint_hash, SSH_FP_DEFAULT);
debug3("%s: key already used: %s %s", __func__,
sshkey_type(authctxt->prev_keys[i]),
fp == NULL ? "UNKNOWN" : fp);
free(fp);
return 1;
}
}
return 0;
}
static void
warn_changed_key(Key *host_key)
{
char *fp;
fp = sshkey_fingerprint(host_key, options.fingerprint_hash,
SSH_FP_DEFAULT);
if (fp == NULL)
fatal("%s: sshkey_fingerprint fail", __func__);
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
error("It is also possible that a host key has just been changed.");
error("The fingerprint for the %s key sent by the remote host is\n%s.",
key_type(host_key), fp);
error("Please contact your system administrator.");
free(fp);
}
/* Returns 1 if key is revoked by revoked_keys_file, 0 otherwise */
int
auth_key_is_revoked(struct sshkey *key)
{
char *fp = NULL;
int r;
if (options.revoked_keys_file == NULL)
return 0;
if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
SSH_FP_DEFAULT)) == NULL) {
r = SSH_ERR_ALLOC_FAIL;
error("%s: fingerprint key: %s", __func__, ssh_err(r));
goto out;
}
r = sshkey_check_revoked(key, options.revoked_keys_file);
switch (r) {
case 0:
break; /* not revoked */
case SSH_ERR_KEY_REVOKED:
error("Authentication key %s %s revoked by file %s",
sshkey_type(key), fp, options.revoked_keys_file);
goto out;
default:
error("Error checking authentication key %s %s in "
"revoked keys file %s: %s", sshkey_type(key), fp,
options.revoked_keys_file, ssh_err(r));
goto out;
}
/* Success */
r = 0;
out:
free(fp);
return r == 0 ? 0 : 1;
}
int
hostfile_replace_entries(const char *filename, const char *host, const char *ip,
struct sshkey **keys, size_t nkeys, int store_hash, int quiet, int hash_alg)
{
int r, fd, oerrno = 0;
int loglevel = quiet ? SYSLOG_LEVEL_DEBUG1 : SYSLOG_LEVEL_VERBOSE;
struct host_delete_ctx ctx;
char *fp, *temp = NULL, *back = NULL;
mode_t omask;
size_t i;
omask = umask(077);
memset(&ctx, 0, sizeof(ctx));
ctx.host = host;
ctx.quiet = quiet;
if ((ctx.skip_keys = calloc(nkeys, sizeof(*ctx.skip_keys))) == NULL)
return SSH_ERR_ALLOC_FAIL;
ctx.keys = keys;
ctx.nkeys = nkeys;
ctx.modified = 0;
/*
* Prepare temporary file for in-place deletion.
*/
if ((r = asprintf(&temp, "%s.XXXXXXXXXXX", filename)) < 0 ||
(r = asprintf(&back, "%s.old", filename)) < 0) {
r = SSH_ERR_ALLOC_FAIL;
goto fail;
}
if ((fd = mkstemp(temp)) == -1) {
oerrno = errno;
error("%s: mkstemp: %s", __func__, strerror(oerrno));
r = SSH_ERR_SYSTEM_ERROR;
goto fail;
}
if ((ctx.out = fdopen(fd, "w")) == NULL) {
oerrno = errno;
close(fd);
error("%s: fdopen: %s", __func__, strerror(oerrno));
r = SSH_ERR_SYSTEM_ERROR;
goto fail;
}
/* Remove all entries for the specified host from the file */
if ((r = hostkeys_foreach(filename, host_delete, &ctx, host, ip,
HKF_WANT_PARSE_KEY)) != 0) {
error("%s: hostkeys_foreach failed: %s", __func__, ssh_err(r));
goto fail;
}
/* Add the requested keys */
for (i = 0; i < nkeys; i++) {
if (ctx.skip_keys[i])
continue;
if ((fp = sshkey_fingerprint(keys[i], hash_alg,
SSH_FP_DEFAULT)) == NULL) {
r = SSH_ERR_ALLOC_FAIL;
goto fail;
}
do_log2(loglevel, "%s%sAdding new key for %s to %s: %s %s",
quiet ? __func__ : "", quiet ? ": " : "", host, filename,
sshkey_ssh_name(keys[i]), fp);
free(fp);
if (!write_host_entry(ctx.out, host, ip, keys[i], store_hash)) {
r = SSH_ERR_INTERNAL_ERROR;
goto fail;
}
ctx.modified = 1;
}
fclose(ctx.out);
ctx.out = NULL;
if (ctx.modified) {
/* Backup the original file and replace it with the temporary */
if (unlink(back) == -1 && errno != ENOENT) {
oerrno = errno;
error("%s: unlink %.100s: %s", __func__,
back, strerror(errno));
r = SSH_ERR_SYSTEM_ERROR;
goto fail;
}
if (link(filename, back) == -1) {
oerrno = errno;
error("%s: link %.100s to %.100s: %s", __func__,
filename, back, strerror(errno));
r = SSH_ERR_SYSTEM_ERROR;
goto fail;
}
if (rename(temp, filename) == -1) {
oerrno = errno;
error("%s: rename \"%s\" to \"%s\": %s", __func__,
temp, filename, strerror(errno));
r = SSH_ERR_SYSTEM_ERROR;
goto fail;
}
} else {
/* No changes made; just delete the temporary file */
if (unlink(temp) != 0)
error("%s: unlink \"%s\": %s", __func__,
temp, strerror(errno));
}
/* success */
r = 0;
fail:
if (temp != NULL && r != 0)
unlink(temp);
free(temp);
free(back);
if (ctx.out != NULL)
fclose(ctx.out);
free(ctx.skip_keys);
umask(omask);
if (r == SSH_ERR_SYSTEM_ERROR)
errno = oerrno;
return r;
}
/* returns 0 if key verifies or -1 if key does NOT verify */
int
verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
{
int r = -1, flags = 0;
char *fp = NULL;
struct sshkey *plain = NULL;
if ((fp = sshkey_fingerprint(host_key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
error("%s: fingerprint host key: %s", __func__, ssh_err(r));
r = -1;
goto out;
}
debug("Server host key: %s %s",
compat20 ? sshkey_ssh_name(host_key) : sshkey_type(host_key), fp);
if (sshkey_equal(previous_host_key, host_key)) {
debug2("%s: server host key %s %s matches cached key",
__func__, sshkey_type(host_key), fp);
r = 0;
goto out;
}
/* Check in RevokedHostKeys file if specified */
if (options.revoked_host_keys != NULL) {
r = sshkey_check_revoked(host_key, options.revoked_host_keys);
switch (r) {
case 0:
break; /* not revoked */
case SSH_ERR_KEY_REVOKED:
error("Host key %s %s revoked by file %s",
sshkey_type(host_key), fp,
options.revoked_host_keys);
r = -1;
goto out;
default:
error("Error checking host key %s %s in "
"revoked keys file %s: %s", sshkey_type(host_key),
fp, options.revoked_host_keys, ssh_err(r));
r = -1;
goto out;
}
}
if (options.verify_host_key_dns) {
/*
* XXX certs are not yet supported for DNS, so downgrade
* them and try the plain key.
*/
if ((r = sshkey_from_private(host_key, &plain)) != 0)
goto out;
if (sshkey_is_cert(plain))
sshkey_drop_cert(plain);
if (verify_host_key_dns(host, hostaddr, plain, &flags) == 0) {
if (flags & DNS_VERIFY_FOUND) {
if (options.verify_host_key_dns == 1 &&
flags & DNS_VERIFY_MATCH &&
flags & DNS_VERIFY_SECURE) {
r = 0;
goto out;
}
if (flags & DNS_VERIFY_MATCH) {
matching_host_key_dns = 1;
} else {
warn_changed_key(plain);
error("Update the SSHFP RR in DNS "
"with the new host key to get rid "
"of this message.");
}
}
}
}
r = check_host_key(host, hostaddr, options.port, host_key, RDRW,
options.user_hostfiles, options.num_user_hostfiles,
options.system_hostfiles, options.num_system_hostfiles);
out:
sshkey_free(plain);
free(fp);
if (r == 0 && host_key != NULL) {
key_free(previous_host_key);
previous_host_key = key_from_private(host_key);
}
return r;
}
void
sshkey_file_tests(void)
{
struct sshkey *k1, *k2;
struct sshbuf *buf, *pw;
BIGNUM *a, *b, *c;
char *cp;
TEST_START("load passphrase");
pw = load_text_file("pw");
TEST_DONE();
#ifdef WITH_SSH1
TEST_START("parse RSA1 from private");
buf = load_file("rsa1_1");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf, "", "rsa1_1",
&k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
a = load_bignum("rsa1_1.param.n");
ASSERT_BIGNUM_EQ(k1->rsa->n, a);
BN_free(a);
TEST_DONE();
TEST_START("parse RSA1 from private w/ passphrase");
buf = load_file("rsa1_1_pw");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
(const char *)sshbuf_ptr(pw), "rsa1_1_pw", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load RSA1 from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("rsa1_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("RSA1 key hex fingerprint");
buf = load_text_file("rsa1_1.fp");
cp = sshkey_fingerprint(k1, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("RSA1 key bubblebabble fingerprint");
buf = load_text_file("rsa1_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_DIGEST_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
#endif
TEST_START("parse RSA from private");
buf = load_file("rsa_1");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf, "", "rsa_1",
&k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
a = load_bignum("rsa_1.param.n");
b = load_bignum("rsa_1.param.p");
c = load_bignum("rsa_1.param.q");
ASSERT_BIGNUM_EQ(k1->rsa->n, a);
ASSERT_BIGNUM_EQ(k1->rsa->p, b);
ASSERT_BIGNUM_EQ(k1->rsa->q, c);
BN_free(a);
BN_free(b);
BN_free(c);
TEST_DONE();
TEST_START("parse RSA from private w/ passphrase");
buf = load_file("rsa_1_pw");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
(const char *)sshbuf_ptr(pw), "rsa_1_pw", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("parse RSA from new-format");
buf = load_file("rsa_n");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
"", "rsa_n", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("parse RSA from new-format w/ passphrase");
buf = load_file("rsa_n_pw");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
(const char *)sshbuf_ptr(pw), "rsa_n_pw", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load RSA from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("rsa_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load RSA cert");
ASSERT_INT_EQ(sshkey_load_cert(test_data_file("rsa_1"), &k2), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(k2->type, KEY_RSA_CERT);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 0);
ASSERT_INT_EQ(sshkey_equal_public(k1, k2), 1);
TEST_DONE();
TEST_START("RSA key hex fingerprint");
buf = load_text_file("rsa_1.fp");
cp = sshkey_fingerprint(k1, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("RSA cert hex fingerprint");
buf = load_text_file("rsa_1-cert.fp");
cp = sshkey_fingerprint(k2, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
sshkey_free(k2);
TEST_DONE();
TEST_START("RSA key bubblebabble fingerprint");
buf = load_text_file("rsa_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_DIGEST_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
TEST_START("parse DSA from private");
buf = load_file("dsa_1");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf, "", "dsa_1",
&k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
a = load_bignum("dsa_1.param.g");
b = load_bignum("dsa_1.param.priv");
c = load_bignum("dsa_1.param.pub");
ASSERT_BIGNUM_EQ(k1->dsa->g, a);
ASSERT_BIGNUM_EQ(k1->dsa->priv_key, b);
ASSERT_BIGNUM_EQ(k1->dsa->pub_key, c);
BN_free(a);
BN_free(b);
BN_free(c);
TEST_DONE();
TEST_START("parse DSA from private w/ passphrase");
buf = load_file("dsa_1_pw");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
(const char *)sshbuf_ptr(pw), "dsa_1_pw", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("parse DSA from new-format");
buf = load_file("dsa_n");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
"", "dsa_n", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("parse DSA from new-format w/ passphrase");
buf = load_file("dsa_n_pw");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
(const char *)sshbuf_ptr(pw), "dsa_n_pw", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load DSA from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("dsa_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load DSA cert");
ASSERT_INT_EQ(sshkey_load_cert(test_data_file("dsa_1"), &k2), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(k2->type, KEY_DSA_CERT);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 0);
ASSERT_INT_EQ(sshkey_equal_public(k1, k2), 1);
TEST_DONE();
TEST_START("DSA key hex fingerprint");
buf = load_text_file("dsa_1.fp");
cp = sshkey_fingerprint(k1, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("DSA cert hex fingerprint");
buf = load_text_file("dsa_1-cert.fp");
cp = sshkey_fingerprint(k2, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
sshkey_free(k2);
TEST_DONE();
TEST_START("DSA key bubblebabble fingerprint");
buf = load_text_file("dsa_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_DIGEST_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
#ifdef OPENSSL_HAS_ECC
TEST_START("parse ECDSA from private");
buf = load_file("ecdsa_1");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf, "", "ecdsa_1",
&k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
buf = load_text_file("ecdsa_1.param.curve");
ASSERT_STRING_EQ((const char *)sshbuf_ptr(buf),
OBJ_nid2sn(k1->ecdsa_nid));
sshbuf_free(buf);
a = load_bignum("ecdsa_1.param.priv");
b = load_bignum("ecdsa_1.param.pub");
c = EC_POINT_point2bn(EC_KEY_get0_group(k1->ecdsa),
EC_KEY_get0_public_key(k1->ecdsa), POINT_CONVERSION_UNCOMPRESSED,
NULL, NULL);
ASSERT_PTR_NE(c, NULL);
ASSERT_BIGNUM_EQ(EC_KEY_get0_private_key(k1->ecdsa), a);
ASSERT_BIGNUM_EQ(b, c);
BN_free(a);
BN_free(b);
BN_free(c);
TEST_DONE();
TEST_START("parse ECDSA from private w/ passphrase");
buf = load_file("ecdsa_1_pw");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
(const char *)sshbuf_ptr(pw), "ecdsa_1_pw", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("parse ECDSA from new-format");
buf = load_file("ecdsa_n");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
"", "ecdsa_n", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("parse ECDSA from new-format w/ passphrase");
buf = load_file("ecdsa_n_pw");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
(const char *)sshbuf_ptr(pw), "ecdsa_n_pw", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load ECDSA from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("ecdsa_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load ECDSA cert");
ASSERT_INT_EQ(sshkey_load_cert(test_data_file("ecdsa_1"), &k2), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(k2->type, KEY_ECDSA_CERT);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 0);
ASSERT_INT_EQ(sshkey_equal_public(k1, k2), 1);
TEST_DONE();
TEST_START("ECDSA key hex fingerprint");
buf = load_text_file("ecdsa_1.fp");
cp = sshkey_fingerprint(k1, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("ECDSA cert hex fingerprint");
buf = load_text_file("ecdsa_1-cert.fp");
cp = sshkey_fingerprint(k2, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
sshkey_free(k2);
TEST_DONE();
TEST_START("ECDSA key bubblebabble fingerprint");
buf = load_text_file("ecdsa_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_DIGEST_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
#endif /* OPENSSL_HAS_ECC */
TEST_START("parse Ed25519 from private");
buf = load_file("ed25519_1");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf, "", "ed25519_1",
&k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
ASSERT_INT_EQ(k1->type, KEY_ED25519);
/* XXX check key contents */
TEST_DONE();
TEST_START("parse Ed25519 from private w/ passphrase");
buf = load_file("ed25519_1_pw");
ASSERT_INT_EQ(sshkey_parse_private_fileblob(buf,
(const char *)sshbuf_ptr(pw), "ed25519_1_pw", &k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load Ed25519 from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("ed25519_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load Ed25519 cert");
ASSERT_INT_EQ(sshkey_load_cert(test_data_file("ed25519_1"), &k2), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(k2->type, KEY_ED25519_CERT);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 0);
ASSERT_INT_EQ(sshkey_equal_public(k1, k2), 1);
TEST_DONE();
TEST_START("Ed25519 key hex fingerprint");
buf = load_text_file("ed25519_1.fp");
cp = sshkey_fingerprint(k1, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("Ed25519 cert hex fingerprint");
buf = load_text_file("ed25519_1-cert.fp");
cp = sshkey_fingerprint(k2, SSH_DIGEST_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
sshkey_free(k2);
TEST_DONE();
TEST_START("Ed25519 key bubblebabble fingerprint");
buf = load_text_file("ed25519_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_DIGEST_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, (const char *)sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
sshbuf_free(pw);
}
/* returns 0 if key verifies or -1 if key does NOT verify */
int
verify_host_key(char *host, struct sockaddr *hostaddr, struct sshkey *host_key)
{
u_int i;
int r = -1, flags = 0;
char valid[64], *fp = NULL, *cafp = NULL;
struct sshkey *plain = NULL;
if ((fp = sshkey_fingerprint(host_key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
error("%s: fingerprint host key: %s", __func__, ssh_err(r));
r = -1;
goto out;
}
if (sshkey_is_cert(host_key)) {
if ((cafp = sshkey_fingerprint(host_key->cert->signature_key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
error("%s: fingerprint CA key: %s",
__func__, ssh_err(r));
r = -1;
goto out;
}
sshkey_format_cert_validity(host_key->cert,
valid, sizeof(valid));
debug("Server host certificate: %s %s, serial %llu "
"ID \"%s\" CA %s %s valid %s",
sshkey_ssh_name(host_key), fp,
(unsigned long long)host_key->cert->serial,
host_key->cert->key_id,
sshkey_ssh_name(host_key->cert->signature_key), cafp,
valid);
for (i = 0; i < host_key->cert->nprincipals; i++) {
debug2("Server host certificate hostname: %s",
host_key->cert->principals[i]);
}
} else {
debug("Server host key: %s %s", sshkey_ssh_name(host_key), fp);
}
if (sshkey_equal(previous_host_key, host_key)) {
debug2("%s: server host key %s %s matches cached key",
__func__, sshkey_type(host_key), fp);
r = 0;
goto out;
}
/* Check in RevokedHostKeys file if specified */
if (options.revoked_host_keys != NULL) {
r = sshkey_check_revoked(host_key, options.revoked_host_keys);
switch (r) {
case 0:
break; /* not revoked */
case SSH_ERR_KEY_REVOKED:
error("Host key %s %s revoked by file %s",
sshkey_type(host_key), fp,
options.revoked_host_keys);
r = -1;
goto out;
default:
error("Error checking host key %s %s in "
"revoked keys file %s: %s", sshkey_type(host_key),
fp, options.revoked_host_keys, ssh_err(r));
r = -1;
goto out;
}
}
if (options.verify_host_key_dns) {
/*
* XXX certs are not yet supported for DNS, so downgrade
* them and try the plain key.
*/
if ((r = sshkey_from_private(host_key, &plain)) != 0)
goto out;
if (sshkey_is_cert(plain))
sshkey_drop_cert(plain);
if (verify_host_key_dns(host, hostaddr, plain, &flags) == 0) {
if (flags & DNS_VERIFY_FOUND) {
if (options.verify_host_key_dns == 1 &&
flags & DNS_VERIFY_MATCH &&
flags & DNS_VERIFY_SECURE) {
r = 0;
goto out;
}
if (flags & DNS_VERIFY_MATCH) {
matching_host_key_dns = 1;
} else {
warn_changed_key(plain);
error("Update the SSHFP RR in DNS "
"with the new host key to get rid "
"of this message.");
}
}
}
}
r = check_host_key(host, hostaddr, options.port, host_key, RDRW,
options.user_hostfiles, options.num_user_hostfiles,
options.system_hostfiles, options.num_system_hostfiles);
out:
sshkey_free(plain);
free(fp);
free(cafp);
if (r == 0 && host_key != NULL) {
sshkey_free(previous_host_key);
r = sshkey_from_private(host_key, &previous_host_key);
}
return r;
}
void
sshkey_file_tests(void)
{
struct sshkey *k1, *k2;
struct sshbuf *buf, *pw;
BIGNUM *a, *b, *c;
char *cp;
TEST_START("load passphrase");
pw = load_text_file("pw");
TEST_DONE();
TEST_START("parse RSA1 from private");
buf = load_file("rsa1_1");
ASSERT_INT_EQ(sshkey_parse_private(buf, "", "rsa1_1", &k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
a = load_bignum("rsa1_1.param.n");
ASSERT_BIGNUM_EQ(k1->rsa->n, a);
BN_free(a);
TEST_DONE();
TEST_START("parse RSA from private w/ passphrase");
buf = load_file("rsa1_1_pw");
ASSERT_INT_EQ(sshkey_parse_private(buf, sshbuf_ptr(pw), "rsa1_1_pw",
&k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load RSA from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("rsa1_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("RSA key hex fingerprint");
buf = load_text_file("rsa1_1.fp");
cp = sshkey_fingerprint(k1, SSH_FP_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("RSA key bubblebabble fingerprint");
buf = load_text_file("rsa1_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_FP_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
TEST_START("parse RSA from private");
buf = load_file("rsa_1");
ASSERT_INT_EQ(sshkey_parse_private(buf, "", "rsa_1", &k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
a = load_bignum("rsa_1.param.n");
b = load_bignum("rsa_1.param.p");
c = load_bignum("rsa_1.param.q");
ASSERT_BIGNUM_EQ(k1->rsa->n, a);
ASSERT_BIGNUM_EQ(k1->rsa->p, b);
ASSERT_BIGNUM_EQ(k1->rsa->q, c);
BN_free(a);
BN_free(b);
BN_free(c);
TEST_DONE();
TEST_START("parse RSA from private w/ passphrase");
buf = load_file("rsa_1_pw");
ASSERT_INT_EQ(sshkey_parse_private(buf, sshbuf_ptr(pw), "rsa_1_pw",
&k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load RSA from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("rsa_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("RSA key hex fingerprint");
buf = load_text_file("rsa_1.fp");
cp = sshkey_fingerprint(k1, SSH_FP_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("RSA key bubblebabble fingerprint");
buf = load_text_file("rsa_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_FP_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
TEST_START("parse DSA from private");
buf = load_file("dsa_1");
ASSERT_INT_EQ(sshkey_parse_private(buf, "", "dsa_1", &k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
a = load_bignum("dsa_1.param.g");
b = load_bignum("dsa_1.param.priv");
c = load_bignum("dsa_1.param.pub");
ASSERT_BIGNUM_EQ(k1->dsa->g, a);
ASSERT_BIGNUM_EQ(k1->dsa->priv_key, b);
ASSERT_BIGNUM_EQ(k1->dsa->pub_key, c);
BN_free(a);
BN_free(b);
BN_free(c);
TEST_DONE();
TEST_START("parse DSA from private w/ passphrase");
buf = load_file("dsa_1_pw");
ASSERT_INT_EQ(sshkey_parse_private(buf, sshbuf_ptr(pw), "dsa_1_pw",
&k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load DSA from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("dsa_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("DSA key hex fingerprint");
buf = load_text_file("dsa_1.fp");
cp = sshkey_fingerprint(k1, SSH_FP_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("DSA key bubblebabble fingerprint");
buf = load_text_file("dsa_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_FP_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
TEST_START("parse ECDSA from private");
buf = load_file("ecdsa_1");
ASSERT_INT_EQ(sshkey_parse_private(buf, "", "ecdsa_1", &k1, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k1, NULL);
buf = load_text_file("ecdsa_1.param.curve");
ASSERT_STRING_EQ(sshbuf_ptr(buf), OBJ_nid2sn(k1->ecdsa_nid));
sshbuf_free(buf);
a = load_bignum("ecdsa_1.param.priv");
b = load_bignum("ecdsa_1.param.pub");
c = EC_POINT_point2bn(EC_KEY_get0_group(k1->ecdsa),
EC_KEY_get0_public_key(k1->ecdsa), POINT_CONVERSION_UNCOMPRESSED,
NULL, NULL);
ASSERT_PTR_NE(c, NULL);
ASSERT_BIGNUM_EQ(EC_KEY_get0_private_key(k1->ecdsa), a);
ASSERT_BIGNUM_EQ(b, c);
BN_free(a);
BN_free(b);
BN_free(c);
TEST_DONE();
TEST_START("parse ECDSA from private w/ passphrase");
buf = load_file("ecdsa_1_pw");
ASSERT_INT_EQ(sshkey_parse_private(buf, sshbuf_ptr(pw), "ecdsa_1_pw",
&k2, NULL), 0);
sshbuf_free(buf);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("load ECDSA from public");
ASSERT_INT_EQ(sshkey_load_public(test_data_file("ecdsa_1.pub"), &k2,
NULL), 0);
ASSERT_PTR_NE(k2, NULL);
ASSERT_INT_EQ(sshkey_equal(k1, k2), 1);
sshkey_free(k2);
TEST_DONE();
TEST_START("ECDSA key hex fingerprint");
buf = load_text_file("ecdsa_1.fp");
cp = sshkey_fingerprint(k1, SSH_FP_MD5, SSH_FP_HEX);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
TEST_START("ECDSA key bubblebabble fingerprint");
buf = load_text_file("ecdsa_1.fp.bb");
cp = sshkey_fingerprint(k1, SSH_FP_SHA1, SSH_FP_BUBBLEBABBLE);
ASSERT_PTR_NE(cp, NULL);
ASSERT_STRING_EQ(cp, sshbuf_ptr(buf));
sshbuf_free(buf);
free(cp);
TEST_DONE();
sshkey_free(k1);
sshbuf_free(pw);
}
/*
* Checks whether key is allowed in authorized_keys-format file,
* returns 1 if the key is allowed or 0 otherwise.
*/
static int
check_authkeys_file(FILE *f, char *file, Key* key, struct passwd *pw)
{
char line[SSH_MAX_PUBKEY_BYTES];
const char *reason;
int found_key = 0;
u_long linenum = 0;
Key *found;
char *fp;
found_key = 0;
found = NULL;
while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
char *cp, *key_options = NULL;
if (found != NULL)
key_free(found);
found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type);
auth_clear_options();
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
if (key_read(found, &cp) != 1) {
/* no key? check if there are options for this key */
int quoted = 0;
debug2("user_key_allowed: check options: '%s'", cp);
key_options = cp;
for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
/* Skip remaining whitespace. */
for (; *cp == ' ' || *cp == '\t'; cp++)
;
if (key_read(found, &cp) != 1) {
debug2("user_key_allowed: advance: '%s'", cp);
/* still no key? advance to next line*/
continue;
}
}
if (key_is_cert(key)) {
if (!key_equal(found, key->cert->signature_key))
continue;
if (auth_parse_options(pw, key_options, file,
linenum) != 1)
continue;
if (!key_is_cert_authority)
continue;
if ((fp = sshkey_fingerprint(found,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
continue;
debug("matching CA found: file %s, line %lu, %s %s",
file, linenum, key_type(found), fp);
/*
* If the user has specified a list of principals as
* a key option, then prefer that list to matching
* their username in the certificate principals list.
*/
if (authorized_principals != NULL &&
!match_principals_option(authorized_principals,
key->cert)) {
reason = "Certificate does not contain an "
"authorized principal";
fail_reason:
free(fp);
error("%s", reason);
auth_debug_add("%s", reason);
continue;
}
if (key_cert_check_authority(key, 0, 0,
authorized_principals == NULL ? pw->pw_name : NULL,
&reason) != 0)
goto fail_reason;
if (auth_cert_options(key, pw) != 0) {
free(fp);
continue;
}
verbose("Accepted certificate ID \"%s\" "
"signed by %s CA %s via %s", key->cert->key_id,
key_type(found), fp, file);
free(fp);
found_key = 1;
break;
} else if (key_equal(found, key)) {
if (auth_parse_options(pw, key_options, file,
linenum) != 1)
continue;
if (key_is_cert_authority)
continue;
if ((fp = sshkey_fingerprint(found,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
continue;
debug("matching key found: file %s, line %lu %s %s",
file, linenum, key_type(found), fp);
free(fp);
found_key = 1;
break;
}
}
if (found != NULL)
key_free(found);
if (!found_key)
debug2("key not found");
return found_key;
}
/* return 1 if given hostkey is allowed */
int
hostbased_key_allowed(struct passwd *pw, const char *cuser, char *chost,
struct sshkey *key)
{
struct ssh *ssh = active_state; /* XXX */
const char *resolvedname, *ipaddr, *lookup, *reason;
HostStatus host_status;
int len;
char *fp;
if (auth_key_is_revoked(key))
return 0;
resolvedname = auth_get_canonical_hostname(ssh, options.use_dns);
ipaddr = ssh_remote_ipaddr(ssh);
debug2("%s: chost %s resolvedname %s ipaddr %s", __func__,
chost, resolvedname, ipaddr);
if (((len = strlen(chost)) > 0) && chost[len - 1] == '.') {
debug2("stripping trailing dot from chost %s", chost);
chost[len - 1] = '\0';
}
if (options.hostbased_uses_name_from_packet_only) {
if (auth_rhosts2(pw, cuser, chost, chost) == 0) {
debug2("%s: auth_rhosts2 refused "
"user \"%.100s\" host \"%.100s\" (from packet)",
__func__, cuser, chost);
return 0;
}
lookup = chost;
} else {
if (strcasecmp(resolvedname, chost) != 0)
logit("userauth_hostbased mismatch: "
"client sends %s, but we resolve %s to %s",
chost, ipaddr, resolvedname);
if (auth_rhosts2(pw, cuser, resolvedname, ipaddr) == 0) {
debug2("%s: auth_rhosts2 refused "
"user \"%.100s\" host \"%.100s\" addr \"%.100s\"",
__func__, cuser, resolvedname, ipaddr);
return 0;
}
lookup = resolvedname;
}
debug2("%s: access allowed by auth_rhosts2", __func__);
if (sshkey_is_cert(key) &&
sshkey_cert_check_authority(key, 1, 0, lookup, &reason)) {
error("%s", reason);
auth_debug_add("%s", reason);
return 0;
}
host_status = check_key_in_hostfiles(pw, key, lookup,
_PATH_SSH_SYSTEM_HOSTFILE,
options.ignore_user_known_hosts ? NULL : _PATH_SSH_USER_HOSTFILE);
/* backward compat if no key has been found. */
if (host_status == HOST_NEW) {
host_status = check_key_in_hostfiles(pw, key, lookup,
_PATH_SSH_SYSTEM_HOSTFILE2,
options.ignore_user_known_hosts ? NULL :
_PATH_SSH_USER_HOSTFILE2);
}
if (host_status == HOST_OK) {
if (sshkey_is_cert(key)) {
if ((fp = sshkey_fingerprint(key->cert->signature_key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
fatal("%s: sshkey_fingerprint fail", __func__);
verbose("Accepted certificate ID \"%s\" signed by "
"%s CA %s from %s@%s", key->cert->key_id,
sshkey_type(key->cert->signature_key), fp,
cuser, lookup);
} else {
if ((fp = sshkey_fingerprint(key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
fatal("%s: sshkey_fingerprint fail", __func__);
verbose("Accepted %s public key %s from %s@%s",
sshkey_type(key), fp, cuser, lookup);
}
free(fp);
}
return (host_status == HOST_OK);
}
/*
* Checks whether key is allowed in output of command.
* returns 1 if the key is allowed or 0 otherwise.
*/
static int
user_key_command_allowed2(struct passwd *user_pw, Key *key)
{
FILE *f = NULL;
int r, ok, found_key = 0;
struct passwd *pw;
int i, uid_swapped = 0, ac = 0;
pid_t pid;
char *username = NULL, *key_fp = NULL, *keytext = NULL;
char *tmp, *command = NULL, **av = NULL;
void (*osigchld)(int);
if (options.authorized_keys_command == NULL)
return 0;
if (options.authorized_keys_command_user == NULL) {
error("No user for AuthorizedKeysCommand specified, skipping");
return 0;
}
/*
* NB. all returns later this function should go via "out" to
* ensure the original SIGCHLD handler is restored properly.
*/
osigchld = signal(SIGCHLD, SIG_DFL);
/* Prepare and verify the user for the command */
username = percent_expand(options.authorized_keys_command_user,
"u", user_pw->pw_name, (char *)NULL);
pw = getpwnam(username);
if (pw == NULL) {
error("AuthorizedKeysCommandUser \"%s\" not found: %s",
username, strerror(errno));
goto out;
}
/* Prepare AuthorizedKeysCommand */
if ((key_fp = sshkey_fingerprint(key, options.fingerprint_hash,
SSH_FP_DEFAULT)) == NULL) {
error("%s: sshkey_fingerprint failed", __func__);
goto out;
}
if ((r = sshkey_to_base64(key, &keytext)) != 0) {
error("%s: sshkey_to_base64 failed: %s", __func__, ssh_err(r));
goto out;
}
/* Turn the command into an argument vector */
if (split_argv(options.authorized_keys_command, &ac, &av) != 0) {
error("AuthorizedKeysCommand \"%s\" contains invalid quotes",
command);
goto out;
}
if (ac == 0) {
error("AuthorizedKeysCommand \"%s\" yielded no arguments",
command);
goto out;
}
for (i = 1; i < ac; i++) {
tmp = percent_expand(av[i],
"u", user_pw->pw_name,
"h", user_pw->pw_dir,
"t", sshkey_ssh_name(key),
"f", key_fp,
"k", keytext,
(char *)NULL);
if (tmp == NULL)
fatal("%s: percent_expand failed", __func__);
free(av[i]);
av[i] = tmp;
}
/* Prepare a printable command for logs, etc. */
command = assemble_argv(ac, av);
/*
* If AuthorizedKeysCommand was run without arguments
* then fall back to the old behaviour of passing the
* target username as a single argument.
*/
if (ac == 1) {
av = xreallocarray(av, ac + 2, sizeof(*av));
av[1] = xstrdup(user_pw->pw_name);
av[2] = NULL;
/* Fix up command too, since it is used in log messages */
free(command);
xasprintf(&command, "%s %s", av[0], av[1]);
}
if ((pid = subprocess("AuthorizedKeysCommand", pw, command,
ac, av, &f)) == 0)
goto out;
uid_swapped = 1;
temporarily_use_uid(pw);
ok = check_authkeys_file(f, options.authorized_keys_command, key, pw);
fclose(f);
f = NULL;
if (exited_cleanly(pid, "AuthorizedKeysCommand", command) != 0)
goto out;
/* Read completed successfully */
found_key = ok;
out:
if (f != NULL)
fclose(f);
signal(SIGCHLD, osigchld);
for (i = 0; i < ac; i++)
free(av[i]);
free(av);
if (uid_swapped)
restore_uid();
free(command);
free(username);
free(key_fp);
free(keytext);
return found_key;
}
static int
userauth_pubkey(Authctxt *authctxt)
{
Buffer b;
Key *key = NULL;
char *pkalg, *userstyle, *fp = NULL;
u_char *pkblob, *sig;
u_int alen, blen, slen;
int have_sig, pktype;
int authenticated = 0;
if (!authctxt->valid) {
debug2("%s: disabled because of invalid user", __func__);
return 0;
}
have_sig = packet_get_char();
if (datafellows & SSH_BUG_PKAUTH) {
debug2("%s: SSH_BUG_PKAUTH", __func__);
/* no explicit pkalg given */
pkblob = packet_get_string(&blen);
buffer_init(&b);
buffer_append(&b, pkblob, blen);
/* so we have to extract the pkalg from the pkblob */
pkalg = buffer_get_string(&b, &alen);
buffer_free(&b);
} else {
pkalg = packet_get_string(&alen);
pkblob = packet_get_string(&blen);
}
pktype = key_type_from_name(pkalg);
if (pktype == KEY_UNSPEC) {
/* this is perfectly legal */
logit("%s: unsupported public key algorithm: %s",
__func__, pkalg);
goto done;
}
key = key_from_blob(pkblob, blen);
if (key == NULL) {
error("%s: cannot decode key: %s", __func__, pkalg);
goto done;
}
if (key->type != pktype) {
error("%s: type mismatch for decoded key "
"(received %d, expected %d)", __func__, key->type, pktype);
goto done;
}
if (key_type_plain(key->type) == KEY_RSA &&
(datafellows & SSH_BUG_RSASIGMD5) != 0) {
logit("Refusing RSA key because client uses unsafe "
"signature scheme");
goto done;
}
fp = sshkey_fingerprint(key, options.fingerprint_hash, SSH_FP_DEFAULT);
if (auth2_userkey_already_used(authctxt, key)) {
logit("refusing previously-used %s key", key_type(key));
goto done;
}
if (match_pattern_list(sshkey_ssh_name(key),
options.pubkey_key_types, 0) != 1) {
logit("%s: key type %s not in PubkeyAcceptedKeyTypes",
__func__, sshkey_ssh_name(key));
goto done;
}
if (have_sig) {
debug3("%s: have signature for %s %s",
__func__, sshkey_type(key), fp);
sig = packet_get_string(&slen);
packet_check_eom();
buffer_init(&b);
if (datafellows & SSH_OLD_SESSIONID) {
buffer_append(&b, session_id2, session_id2_len);
} else {
buffer_put_string(&b, session_id2, session_id2_len);
}
/* reconstruct packet */
buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
xasprintf(&userstyle, "%s%s%s", authctxt->user,
authctxt->style ? ":" : "",
authctxt->style ? authctxt->style : "");
buffer_put_cstring(&b, userstyle);
free(userstyle);
buffer_put_cstring(&b,
datafellows & SSH_BUG_PKSERVICE ?
"ssh-userauth" :
authctxt->service);
if (datafellows & SSH_BUG_PKAUTH) {
buffer_put_char(&b, have_sig);
} else {
buffer_put_cstring(&b, "publickey");
buffer_put_char(&b, have_sig);
buffer_put_cstring(&b, pkalg);
}
buffer_put_string(&b, pkblob, blen);
#ifdef DEBUG_PK
buffer_dump(&b);
#endif
pubkey_auth_info(authctxt, key, NULL);
/* test for correct signature */
authenticated = 0;
if (PRIVSEP(user_key_allowed(authctxt->pw, key, 1)) &&
PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b),
buffer_len(&b))) == 1) {
authenticated = 1;
/* Record the successful key to prevent reuse */
auth2_record_userkey(authctxt, key);
key = NULL; /* Don't free below */
}
buffer_free(&b);
free(sig);
} else {
debug("%s: test whether pkalg/pkblob are acceptable for %s %s",
__func__, sshkey_type(key), fp);
packet_check_eom();
/* XXX fake reply and always send PK_OK ? */
/*
* XXX this allows testing whether a user is allowed
* to login: if you happen to have a valid pubkey this
* message is sent. the message is NEVER sent at all
* if a user is not allowed to login. is this an
* issue? -markus
*/
if (PRIVSEP(user_key_allowed(authctxt->pw, key, 0))) {
packet_start(SSH2_MSG_USERAUTH_PK_OK);
packet_put_string(pkalg, alen);
packet_put_string(pkblob, blen);
packet_send();
packet_write_wait();
authctxt->postponed = 1;
}
}
if (authenticated != 1)
auth_clear_options();
done:
debug2("%s: authenticated %d pkalg %s", __func__, authenticated, pkalg);
if (key != NULL)
key_free(key);
free(pkalg);
free(pkblob);
free(fp);
return authenticated;
}
/*
* Checks whether principal is allowed in output of command.
* returns 1 if the principal is allowed or 0 otherwise.
*/
static int
match_principals_command(struct passwd *user_pw, const struct sshkey *key)
{
const struct sshkey_cert *cert = key->cert;
FILE *f = NULL;
int r, ok, found_principal = 0;
struct passwd *pw;
int i, ac = 0, uid_swapped = 0;
pid_t pid;
char *tmp, *username = NULL, *command = NULL, **av = NULL;
char *ca_fp = NULL, *key_fp = NULL, *catext = NULL, *keytext = NULL;
char serial_s[16];
void (*osigchld)(int);
if (options.authorized_principals_command == NULL)
return 0;
if (options.authorized_principals_command_user == NULL) {
error("No user for AuthorizedPrincipalsCommand specified, "
"skipping");
return 0;
}
/*
* NB. all returns later this function should go via "out" to
* ensure the original SIGCHLD handler is restored properly.
*/
osigchld = signal(SIGCHLD, SIG_DFL);
/* Prepare and verify the user for the command */
username = percent_expand(options.authorized_principals_command_user,
"u", user_pw->pw_name, (char *)NULL);
pw = getpwnam(username);
if (pw == NULL) {
error("AuthorizedPrincipalsCommandUser \"%s\" not found: %s",
username, strerror(errno));
goto out;
}
/* Turn the command into an argument vector */
if (split_argv(options.authorized_principals_command, &ac, &av) != 0) {
error("AuthorizedPrincipalsCommand \"%s\" contains "
"invalid quotes", command);
goto out;
}
if (ac == 0) {
error("AuthorizedPrincipalsCommand \"%s\" yielded no arguments",
command);
goto out;
}
if ((ca_fp = sshkey_fingerprint(cert->signature_key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
error("%s: sshkey_fingerprint failed", __func__);
goto out;
}
if ((key_fp = sshkey_fingerprint(key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
error("%s: sshkey_fingerprint failed", __func__);
goto out;
}
if ((r = sshkey_to_base64(cert->signature_key, &catext)) != 0) {
error("%s: sshkey_to_base64 failed: %s", __func__, ssh_err(r));
goto out;
}
if ((r = sshkey_to_base64(key, &keytext)) != 0) {
error("%s: sshkey_to_base64 failed: %s", __func__, ssh_err(r));
goto out;
}
snprintf(serial_s, sizeof(serial_s), "%llu",
(unsigned long long)cert->serial);
for (i = 1; i < ac; i++) {
tmp = percent_expand(av[i],
"u", user_pw->pw_name,
"h", user_pw->pw_dir,
"t", sshkey_ssh_name(key),
"T", sshkey_ssh_name(cert->signature_key),
"f", key_fp,
"F", ca_fp,
"k", keytext,
"K", catext,
"i", cert->key_id,
"s", serial_s,
(char *)NULL);
if (tmp == NULL)
fatal("%s: percent_expand failed", __func__);
free(av[i]);
av[i] = tmp;
}
/* Prepare a printable command for logs, etc. */
command = assemble_argv(ac, av);
if ((pid = subprocess("AuthorizedPrincipalsCommand", pw, command,
ac, av, &f)) == 0)
goto out;
uid_swapped = 1;
temporarily_use_uid(pw);
ok = process_principals(f, NULL, pw, cert);
fclose(f);
f = NULL;
if (exited_cleanly(pid, "AuthorizedPrincipalsCommand", command) != 0)
goto out;
/* Read completed successfully */
found_principal = ok;
out:
if (f != NULL)
fclose(f);
signal(SIGCHLD, osigchld);
for (i = 0; i < ac; i++)
free(av[i]);
free(av);
if (uid_swapped)
restore_uid();
free(command);
free(username);
free(ca_fp);
free(key_fp);
free(catext);
free(keytext);
return found_principal;
}
static int
check_host_key(char *hostname, struct sockaddr *hostaddr, u_short port,
Key *host_key, int readonly,
char **user_hostfiles, u_int num_user_hostfiles,
char **system_hostfiles, u_int num_system_hostfiles)
{
HostStatus host_status;
HostStatus ip_status;
Key *raw_key = NULL;
char *ip = NULL, *host = NULL;
char hostline[1000], *hostp, *fp, *ra;
char msg[1024];
const char *type;
const struct hostkey_entry *host_found, *ip_found;
int len, cancelled_forwarding = 0;
int local = sockaddr_is_local(hostaddr);
int r, want_cert = key_is_cert(host_key), host_ip_differ = 0;
int hostkey_trusted = 0; /* Known or explicitly accepted by user */
struct hostkeys *host_hostkeys, *ip_hostkeys;
u_int i;
/*
* Force accepting of the host key for loopback/localhost. The
* problem is that if the home directory is NFS-mounted to multiple
* machines, localhost will refer to a different machine in each of
* them, and the user will get bogus HOST_CHANGED warnings. This
* essentially disables host authentication for localhost; however,
* this is probably not a real problem.
*/
if (options.no_host_authentication_for_localhost == 1 && local &&
options.host_key_alias == NULL) {
debug("Forcing accepting of host key for "
"loopback/localhost.");
return 0;
}
/*
* Prepare the hostname and address strings used for hostkey lookup.
* In some cases, these will have a port number appended.
*/
get_hostfile_hostname_ipaddr(hostname, hostaddr, port, &host, &ip);
/*
* Turn off check_host_ip if the connection is to localhost, via proxy
* command or if we don't have a hostname to compare with
*/
if (options.check_host_ip && (local ||
strcmp(hostname, ip) == 0 || options.proxy_command != NULL))
options.check_host_ip = 0;
host_hostkeys = init_hostkeys();
for (i = 0; i < num_user_hostfiles; i++)
load_hostkeys(host_hostkeys, host, user_hostfiles[i]);
for (i = 0; i < num_system_hostfiles; i++)
load_hostkeys(host_hostkeys, host, system_hostfiles[i]);
ip_hostkeys = NULL;
if (!want_cert && options.check_host_ip) {
ip_hostkeys = init_hostkeys();
for (i = 0; i < num_user_hostfiles; i++)
load_hostkeys(ip_hostkeys, ip, user_hostfiles[i]);
for (i = 0; i < num_system_hostfiles; i++)
load_hostkeys(ip_hostkeys, ip, system_hostfiles[i]);
}
retry:
/* Reload these as they may have changed on cert->key downgrade */
want_cert = key_is_cert(host_key);
type = key_type(host_key);
/*
* Check if the host key is present in the user's list of known
* hosts or in the systemwide list.
*/
host_status = check_key_in_hostkeys(host_hostkeys, host_key,
&host_found);
/*
* Also perform check for the ip address, skip the check if we are
* localhost, looking for a certificate, or the hostname was an ip
* address to begin with.
*/
if (!want_cert && ip_hostkeys != NULL) {
ip_status = check_key_in_hostkeys(ip_hostkeys, host_key,
&ip_found);
if (host_status == HOST_CHANGED &&
(ip_status != HOST_CHANGED ||
(ip_found != NULL &&
!key_equal(ip_found->key, host_found->key))))
host_ip_differ = 1;
} else
ip_status = host_status;
switch (host_status) {
case HOST_OK:
/* The host is known and the key matches. */
debug("Host '%.200s' is known and matches the %s host %s.",
host, type, want_cert ? "certificate" : "key");
debug("Found %s in %s:%lu", want_cert ? "CA key" : "key",
host_found->file, host_found->line);
if (want_cert && !check_host_cert(hostname, host_key))
goto fail;
if (options.check_host_ip && ip_status == HOST_NEW) {
if (readonly || want_cert)
logit("%s host key for IP address "
"'%.128s' not in list of known hosts.",
type, ip);
else if (!add_host_to_hostfile(user_hostfiles[0], ip,
host_key, options.hash_known_hosts))
logit("Failed to add the %s host key for IP "
"address '%.128s' to the list of known "
"hosts (%.500s).", type, ip,
user_hostfiles[0]);
else
logit("Warning: Permanently added the %s host "
"key for IP address '%.128s' to the list "
"of known hosts.", type, ip);
} else if (options.visual_host_key) {
fp = sshkey_fingerprint(host_key,
options.fingerprint_hash, SSH_FP_DEFAULT);
ra = sshkey_fingerprint(host_key,
options.fingerprint_hash, SSH_FP_RANDOMART);
if (fp == NULL || ra == NULL)
fatal("%s: sshkey_fingerprint fail", __func__);
logit("Host key fingerprint is %s\n%s\n", fp, ra);
free(ra);
free(fp);
}
hostkey_trusted = 1;
break;
case HOST_NEW:
if (options.host_key_alias == NULL && port != 0 &&
port != SSH_DEFAULT_PORT) {
debug("checking without port identifier");
if (check_host_key(hostname, hostaddr, 0, host_key,
ROQUIET, user_hostfiles, num_user_hostfiles,
system_hostfiles, num_system_hostfiles) == 0) {
debug("found matching key w/out port");
break;
}
}
if (readonly || want_cert)
goto fail;
/* The host is new. */
if (options.strict_host_key_checking == 1) {
/*
* User has requested strict host key checking. We
* will not add the host key automatically. The only
* alternative left is to abort.
*/
error("No %s host key is known for %.200s and you "
"have requested strict checking.", type, host);
goto fail;
} else if (options.strict_host_key_checking == 2) {
char msg1[1024], msg2[1024];
if (show_other_keys(host_hostkeys, host_key))
snprintf(msg1, sizeof(msg1),
"\nbut keys of different type are already"
" known for this host.");
else
snprintf(msg1, sizeof(msg1), ".");
/* The default */
fp = sshkey_fingerprint(host_key,
options.fingerprint_hash, SSH_FP_DEFAULT);
ra = sshkey_fingerprint(host_key,
options.fingerprint_hash, SSH_FP_RANDOMART);
if (fp == NULL || ra == NULL)
fatal("%s: sshkey_fingerprint fail", __func__);
msg2[0] = '\0';
if (options.verify_host_key_dns) {
if (matching_host_key_dns)
snprintf(msg2, sizeof(msg2),
"Matching host key fingerprint"
" found in DNS.\n");
else
snprintf(msg2, sizeof(msg2),
"No matching host key fingerprint"
" found in DNS.\n");
}
snprintf(msg, sizeof(msg),
"The authenticity of host '%.200s (%s)' can't be "
"established%s\n"
"%s key fingerprint is %s.%s%s\n%s"
"Are you sure you want to continue connecting "
"(yes/no)? ",
host, ip, msg1, type, fp,
options.visual_host_key ? "\n" : "",
options.visual_host_key ? ra : "",
msg2);
free(ra);
free(fp);
if (!confirm(msg))
goto fail;
hostkey_trusted = 1; /* user explicitly confirmed */
}
/*
* If not in strict mode, add the key automatically to the
* local known_hosts file.
*/
if (options.check_host_ip && ip_status == HOST_NEW) {
snprintf(hostline, sizeof(hostline), "%s,%s", host, ip);
hostp = hostline;
if (options.hash_known_hosts) {
/* Add hash of host and IP separately */
r = add_host_to_hostfile(user_hostfiles[0],
host, host_key, options.hash_known_hosts) &&
add_host_to_hostfile(user_hostfiles[0], ip,
host_key, options.hash_known_hosts);
} else {
/* Add unhashed "host,ip" */
r = add_host_to_hostfile(user_hostfiles[0],
hostline, host_key,
options.hash_known_hosts);
}
} else {
r = add_host_to_hostfile(user_hostfiles[0], host,
host_key, options.hash_known_hosts);
hostp = host;
}
if (!r)
logit("Failed to add the host to the list of known "
"hosts (%.500s).", user_hostfiles[0]);
else
logit("Warning: Permanently added '%.200s' (%s) to the "
"list of known hosts.", hostp, type);
break;
case HOST_REVOKED:
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("@ WARNING: REVOKED HOST KEY DETECTED! @");
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("The %s host key for %s is marked as revoked.", type, host);
error("This could mean that a stolen key is being used to");
error("impersonate this host.");
/*
* If strict host key checking is in use, the user will have
* to edit the key manually and we can only abort.
*/
if (options.strict_host_key_checking) {
error("%s host key for %.200s was revoked and you have "
"requested strict checking.", type, host);
goto fail;
}
goto continue_unsafe;
case HOST_CHANGED:
if (want_cert) {
/*
* This is only a debug() since it is valid to have
* CAs with wildcard DNS matches that don't match
* all hosts that one might visit.
*/
debug("Host certificate authority does not "
"match %s in %s:%lu", CA_MARKER,
host_found->file, host_found->line);
goto fail;
}
if (readonly == ROQUIET)
goto fail;
if (options.check_host_ip && host_ip_differ) {
char *key_msg;
if (ip_status == HOST_NEW)
key_msg = "is unknown";
else if (ip_status == HOST_OK)
key_msg = "is unchanged";
else
key_msg = "has a different value";
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("The %s host key for %s has changed,", type, host);
error("and the key for the corresponding IP address %s", ip);
error("%s. This could either mean that", key_msg);
error("DNS SPOOFING is happening or the IP address for the host");
error("and its host key have changed at the same time.");
if (ip_status != HOST_NEW)
error("Offending key for IP in %s:%lu",
ip_found->file, ip_found->line);
}
/* The host key has changed. */
warn_changed_key(host_key);
error("Add correct host key in %.100s to get rid of this message.",
user_hostfiles[0]);
error("Offending %s key in %s:%lu", key_type(host_found->key),
host_found->file, host_found->line);
/*
* If strict host key checking is in use, the user will have
* to edit the key manually and we can only abort.
*/
if (options.strict_host_key_checking) {
error("%s host key for %.200s has changed and you have "
"requested strict checking.", type, host);
goto fail;
}
continue_unsafe:
/*
* If strict host key checking has not been requested, allow
* the connection but without MITM-able authentication or
* forwarding.
*/
if (options.password_authentication) {
error("Password authentication is disabled to avoid "
"man-in-the-middle attacks.");
options.password_authentication = 0;
cancelled_forwarding = 1;
}
if (options.kbd_interactive_authentication) {
error("Keyboard-interactive authentication is disabled"
" to avoid man-in-the-middle attacks.");
options.kbd_interactive_authentication = 0;
options.challenge_response_authentication = 0;
cancelled_forwarding = 1;
}
if (options.challenge_response_authentication) {
error("Challenge/response authentication is disabled"
" to avoid man-in-the-middle attacks.");
options.challenge_response_authentication = 0;
cancelled_forwarding = 1;
}
if (options.forward_agent) {
error("Agent forwarding is disabled to avoid "
"man-in-the-middle attacks.");
options.forward_agent = 0;
cancelled_forwarding = 1;
}
if (options.forward_x11) {
error("X11 forwarding is disabled to avoid "
"man-in-the-middle attacks.");
options.forward_x11 = 0;
cancelled_forwarding = 1;
}
if (options.num_local_forwards > 0 ||
options.num_remote_forwards > 0) {
error("Port forwarding is disabled to avoid "
"man-in-the-middle attacks.");
options.num_local_forwards =
options.num_remote_forwards = 0;
cancelled_forwarding = 1;
}
if (options.tun_open != SSH_TUNMODE_NO) {
error("Tunnel forwarding is disabled to avoid "
"man-in-the-middle attacks.");
options.tun_open = SSH_TUNMODE_NO;
cancelled_forwarding = 1;
}
if (options.exit_on_forward_failure && cancelled_forwarding)
fatal("Error: forwarding disabled due to host key "
"check failure");
/*
* XXX Should permit the user to change to use the new id.
* This could be done by converting the host key to an
* identifying sentence, tell that the host identifies itself
* by that sentence, and ask the user if he/she wishes to
* accept the authentication.
*/
break;
case HOST_FOUND:
fatal("internal error");
break;
}
if (options.check_host_ip && host_status != HOST_CHANGED &&
ip_status == HOST_CHANGED) {
snprintf(msg, sizeof(msg),
"Warning: the %s host key for '%.200s' "
"differs from the key for the IP address '%.128s'"
"\nOffending key for IP in %s:%lu",
type, host, ip, ip_found->file, ip_found->line);
if (host_status == HOST_OK) {
len = strlen(msg);
snprintf(msg + len, sizeof(msg) - len,
"\nMatching host key in %s:%lu",
host_found->file, host_found->line);
}
if (options.strict_host_key_checking == 1) {
logit("%s", msg);
error("Exiting, you have requested strict checking.");
goto fail;
} else if (options.strict_host_key_checking == 2) {
strlcat(msg, "\nAre you sure you want "
"to continue connecting (yes/no)? ", sizeof(msg));
if (!confirm(msg))
goto fail;
} else {
logit("%s", msg);
}
}
if (!hostkey_trusted && options.update_hostkeys) {
debug("%s: hostkey not known or explicitly trusted: "
"disabling UpdateHostkeys", __func__);
options.update_hostkeys = 0;
}
free(ip);
free(host);
if (host_hostkeys != NULL)
free_hostkeys(host_hostkeys);
if (ip_hostkeys != NULL)
free_hostkeys(ip_hostkeys);
return 0;
fail:
if (want_cert && host_status != HOST_REVOKED) {
/*
* No matching certificate. Downgrade cert to raw key and
* search normally.
*/
debug("No matching CA found. Retry with plain key");
raw_key = key_from_private(host_key);
if (key_drop_cert(raw_key) != 0)
fatal("Couldn't drop certificate");
host_key = raw_key;
goto retry;
}
if (raw_key != NULL)
key_free(raw_key);
free(ip);
free(host);
if (host_hostkeys != NULL)
free_hostkeys(host_hostkeys);
if (ip_hostkeys != NULL)
free_hostkeys(ip_hostkeys);
return -1;
}
int
main(int argc, char **argv)
{
struct sshbuf *b;
Options options;
#define NUM_KEYTYPES 4
struct sshkey *keys[NUM_KEYTYPES], *key = NULL;
struct passwd *pw;
int r, key_fd[NUM_KEYTYPES], i, found, version = 2, fd;
u_char *signature, *data, rver;
char *host, *fp;
size_t slen, dlen;
#ifdef WITH_OPENSSL
u_int32_t rnd[256];
#endif
if (pledge("stdio rpath getpw dns id", NULL) != 0)
fatal("%s: pledge: %s", __progname, strerror(errno));
/* Ensure that stdin and stdout are connected */
if ((fd = open(_PATH_DEVNULL, O_RDWR)) < 2)
exit(1);
/* Leave /dev/null fd iff it is attached to stderr */
if (fd > 2)
close(fd);
i = 0;
/* XXX This really needs to read sshd_config for the paths */
key_fd[i++] = open(_PATH_HOST_DSA_KEY_FILE, O_RDONLY);
key_fd[i++] = open(_PATH_HOST_ECDSA_KEY_FILE, O_RDONLY);
key_fd[i++] = open(_PATH_HOST_ED25519_KEY_FILE, O_RDONLY);
key_fd[i++] = open(_PATH_HOST_RSA_KEY_FILE, O_RDONLY);
original_real_uid = getuid(); /* XXX readconf.c needs this */
if ((pw = getpwuid(original_real_uid)) == NULL)
fatal("getpwuid failed");
pw = pwcopy(pw);
permanently_set_uid(pw);
seed_rng();
#ifdef DEBUG_SSH_KEYSIGN
log_init("ssh-keysign", SYSLOG_LEVEL_DEBUG3, SYSLOG_FACILITY_AUTH, 0);
#endif
/* verify that ssh-keysign is enabled by the admin */
initialize_options(&options);
(void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, "", "", &options, 0);
fill_default_options(&options);
if (options.enable_ssh_keysign != 1)
fatal("ssh-keysign not enabled in %s",
_PATH_HOST_CONFIG_FILE);
for (i = found = 0; i < NUM_KEYTYPES; i++) {
if (key_fd[i] != -1)
found = 1;
}
if (found == 0)
fatal("could not open any host key");
#ifdef WITH_OPENSSL
OpenSSL_add_all_algorithms();
arc4random_buf(rnd, sizeof(rnd));
RAND_seed(rnd, sizeof(rnd));
#endif
found = 0;
for (i = 0; i < NUM_KEYTYPES; i++) {
keys[i] = NULL;
if (key_fd[i] == -1)
continue;
r = sshkey_load_private_type_fd(key_fd[i], KEY_UNSPEC,
NULL, &key, NULL);
close(key_fd[i]);
if (r != 0)
debug("parse key %d: %s", i, ssh_err(r));
else if (key != NULL) {
keys[i] = key;
found = 1;
}
}
if (!found)
fatal("no hostkey found");
if (pledge("stdio dns", NULL) != 0)
fatal("%s: pledge: %s", __progname, strerror(errno));
if ((b = sshbuf_new()) == NULL)
fatal("%s: sshbuf_new failed", __progname);
if (ssh_msg_recv(STDIN_FILENO, b) < 0)
fatal("ssh_msg_recv failed");
if ((r = sshbuf_get_u8(b, &rver)) != 0)
fatal("%s: buffer error: %s", __progname, ssh_err(r));
if (rver != version)
fatal("bad version: received %d, expected %d", rver, version);
if ((r = sshbuf_get_u32(b, (u_int *)&fd)) != 0)
fatal("%s: buffer error: %s", __progname, ssh_err(r));
if (fd < 0 || fd == STDIN_FILENO || fd == STDOUT_FILENO)
fatal("bad fd");
if ((host = get_local_name(fd)) == NULL)
fatal("cannot get local name for fd");
if ((r = sshbuf_get_string(b, &data, &dlen)) != 0)
fatal("%s: buffer error: %s", __progname, ssh_err(r));
if (valid_request(pw, host, &key, data, dlen) < 0)
fatal("not a valid request");
free(host);
found = 0;
for (i = 0; i < NUM_KEYTYPES; i++) {
if (keys[i] != NULL &&
sshkey_equal_public(key, keys[i])) {
found = 1;
break;
}
}
if (!found) {
if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
SSH_FP_DEFAULT)) == NULL)
fatal("%s: sshkey_fingerprint failed", __progname);
fatal("no matching hostkey found for key %s %s",
sshkey_type(key), fp ? fp : "");
}
if ((r = sshkey_sign(keys[i], &signature, &slen, data, dlen, NULL, 0))
!= 0)
fatal("sshkey_sign failed: %s", ssh_err(r));
free(data);
/* send reply */
sshbuf_reset(b);
if ((r = sshbuf_put_string(b, signature, slen)) != 0)
fatal("%s: buffer error: %s", __progname, ssh_err(r));
if (ssh_msg_send(STDOUT_FILENO, version, b) == -1)
fatal("ssh_msg_send failed");
return (0);
}
