diff --git a/block/ssh.c b/block/ssh.c index ac01301409..a64db146db 100644 --- a/block/ssh.c +++ b/block/ssh.c @@ -386,14 +386,28 @@ static int compare_fingerprint(const unsigned char *fingerprint, size_t len, return *host_key_check - '\0'; } +static char *format_fingerprint(const unsigned char *fingerprint, size_t len) +{ + static const char *hex = "0123456789abcdef"; + char *ret = g_new0(char, (len * 2) + 1); + for (size_t i = 0; i < len; i++) { + ret[i * 2] = hex[((fingerprint[i] >> 4) & 0xf)]; + ret[(i * 2) + 1] = hex[(fingerprint[i] & 0xf)]; + } + ret[len * 2] = '\0'; + return ret; +} + static int check_host_key_hash(BDRVSSHState *s, const char *hash, - enum ssh_publickey_hash_type type, Error **errp) + enum ssh_publickey_hash_type type, const char *typestr, + Error **errp) { int r; ssh_key pubkey; unsigned char *server_hash; size_t server_hash_len; + const char *keytype; r = ssh_get_server_publickey(s->session, &pubkey); if (r != SSH_OK) { @@ -401,6 +415,8 @@ check_host_key_hash(BDRVSSHState *s, const char *hash, return -EINVAL; } + keytype = ssh_key_type_to_char(ssh_key_type(pubkey)); + r = ssh_get_publickey_hash(pubkey, type, &server_hash, &server_hash_len); ssh_key_free(pubkey); if (r != 0) { @@ -410,12 +426,16 @@ check_host_key_hash(BDRVSSHState *s, const char *hash, } r = compare_fingerprint(server_hash, server_hash_len, hash); - ssh_clean_pubkey_hash(&server_hash); if (r != 0) { - error_setg(errp, "remote host key does not match host_key_check '%s'", - hash); + g_autofree char *server_fp = format_fingerprint(server_hash, + server_hash_len); + error_setg(errp, "remote host %s key fingerprint '%s:%s' " + "does not match host_key_check '%s:%s'", + keytype, typestr, server_fp, typestr, hash); + ssh_clean_pubkey_hash(&server_hash); return -EPERM; } + ssh_clean_pubkey_hash(&server_hash); return 0; } @@ -436,13 +456,16 @@ static int check_host_key(BDRVSSHState *s, SshHostKeyCheck *hkc, Error **errp) case SSH_HOST_KEY_CHECK_MODE_HASH: if (hkc->u.hash.type == SSH_HOST_KEY_CHECK_HASH_TYPE_MD5) { return check_host_key_hash(s, hkc->u.hash.hash, - SSH_PUBLICKEY_HASH_MD5, errp); + SSH_PUBLICKEY_HASH_MD5, "md5", + errp); } else if (hkc->u.hash.type == SSH_HOST_KEY_CHECK_HASH_TYPE_SHA1) { return check_host_key_hash(s, hkc->u.hash.hash, - SSH_PUBLICKEY_HASH_SHA1, errp); + SSH_PUBLICKEY_HASH_SHA1, "sha1", + errp); } else if (hkc->u.hash.type == SSH_HOST_KEY_CHECK_HASH_TYPE_SHA256) { return check_host_key_hash(s, hkc->u.hash.hash, - SSH_PUBLICKEY_HASH_SHA256, errp); + SSH_PUBLICKEY_HASH_SHA256, "sha256", + errp); } g_assert_not_reached(); break;