diff options
| -rw-r--r-- | lib/ssh.c | 71 |
1 files changed, 39 insertions, 32 deletions
@@ -639,6 +639,43 @@ static CURLcode ssh_knownhost(struct connectdata *conn) return result; } +static bool ssh_check_fingerprint(struct connectdata *conn) +{ + struct ssh_conn *sshc = &conn->proto.sshc; + struct SessionHandle *data = conn->data; + const char *pubkey_md5 = data->set.str[STRING_SSH_HOST_PUBLIC_KEY_MD5]; + char md5buffer[33]; + int i; + + const char *fingerprint = libssh2_hostkey_hash(sshc->ssh_session, + LIBSSH2_HOSTKEY_HASH_MD5); + + /* The fingerprint points to static storage (!), don't free() it. */ + for(i = 0; i < 16; i++) + snprintf(&md5buffer[i*2], 3, "%02x", (unsigned char) fingerprint[i]); + infof(data, "SSH MD5 fingerprint: %s\n", md5buffer); + + /* Before we authenticate we check the hostkey's MD5 fingerprint + * against a known fingerprint, if available. + */ + if(pubkey_md5 && strlen(pubkey_md5) == 32) { + if(!strequal(md5buffer, pubkey_md5)) { + failf(data, + "Denied establishing ssh session: mismatch md5 fingerprint. " + "Remote %s is not equal to %s", md5buffer, pubkey_md5); + state(conn, SSH_SESSION_FREE); + sshc->actualcode = CURLE_PEER_FAILED_VERIFICATION; + return sshc->actualcode; + } + else { + infof(data, "MD5 checksum match!\n"); + /* as we already matched, we skip the check for known hosts */ + return CURLE_OK; + } + } + else + return ssh_knownhost(conn); +} /* * ssh_statemach_act() runs the SSH state machine as far as it can without @@ -654,10 +691,8 @@ static CURLcode ssh_statemach_act(struct connectdata *conn, bool *block) struct SSHPROTO *sftp_scp = data->state.proto.ssh; struct ssh_conn *sshc = &conn->proto.sshc; curl_socket_t sock = conn->sock[FIRSTSOCKET]; - const char *fingerprint; - char md5buffer[33]; char *new_readdir_line; - int rc = LIBSSH2_ERROR_NONE, i; + int rc = LIBSSH2_ERROR_NONE; int err; int seekerr = CURL_SEEKFUNC_OK; *block = 0; /* we're not blocking by default */ @@ -698,35 +733,7 @@ static CURLcode ssh_statemach_act(struct connectdata *conn, bool *block) * against our known hosts. How that is handled (reading from file, * whatever) is up to us. */ - fingerprint = libssh2_hostkey_hash(sshc->ssh_session, - LIBSSH2_HOSTKEY_HASH_MD5); - - /* The fingerprint points to static storage (!), don't free() it. */ - for(i = 0; i < 16; i++) - snprintf(&md5buffer[i*2], 3, "%02x", (unsigned char) fingerprint[i]); - infof(data, "SSH MD5 fingerprint: %s\n", md5buffer); - - /* Before we authenticate we check the hostkey's MD5 fingerprint - * against a known fingerprint, if available. - */ - if(data->set.str[STRING_SSH_HOST_PUBLIC_KEY_MD5] && - strlen(data->set.str[STRING_SSH_HOST_PUBLIC_KEY_MD5]) == 32) { - if(!strequal(md5buffer, - data->set.str[STRING_SSH_HOST_PUBLIC_KEY_MD5])) { - failf(data, - "Denied establishing ssh session: mismatch md5 fingerprint. " - "Remote %s is not equal to %s", - md5buffer, data->set.str[STRING_SSH_HOST_PUBLIC_KEY_MD5]); - state(conn, SSH_SESSION_FREE); - result = sshc->actualcode = CURLE_PEER_FAILED_VERIFICATION; - } - else - infof(data, "MD5 checksum match!\n"); - /* as we already matched, we skip the check for known hosts */ - } - else - result = ssh_knownhost(conn); - + result = ssh_check_fingerprint(conn); if(!result) state(conn, SSH_AUTHLIST); break; |