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/*
* This file is part of the SSH Library
*
* Copyright (c) 2011-2013 by Aris Adamantiadis
*
* The SSH Library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at your
* option) any later version.
*
* The SSH Library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with the SSH Library; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
* MA 02111-1307, USA.
*/
#include "config.h"
#include "libssh/session.h"
#include "libssh/ecdh.h"
#include "libssh/dh.h"
#include "libssh/buffer.h"
#include "libssh/ssh2.h"
#include "libssh/pki.h"
#include "libssh/bignum.h"
#ifdef HAVE_ECDH
static SSH_PACKET_CALLBACK(ssh_packet_client_ecdh_reply);
static ssh_packet_callback ecdh_client_callbacks[]= {
ssh_packet_client_ecdh_reply
};
struct ssh_packet_callbacks_struct ssh_ecdh_client_callbacks = {
.start = SSH2_MSG_KEX_ECDH_REPLY,
.n_callbacks = 1,
.callbacks = ecdh_client_callbacks,
.user = NULL
};
/** @internal
* @brief parses a SSH_MSG_KEX_ECDH_REPLY packet and sends back
* a SSH_MSG_NEWKEYS
*/
SSH_PACKET_CALLBACK(ssh_packet_client_ecdh_reply){
ssh_string q_s_string = NULL;
ssh_string pubkey_blob = NULL;
ssh_string signature = NULL;
int rc;
(void)type;
(void)user;
ssh_packet_remove_callbacks(session, &ssh_ecdh_client_callbacks);
pubkey_blob = ssh_buffer_get_ssh_string(packet);
if (pubkey_blob == NULL) {
ssh_set_error(session,SSH_FATAL, "No public key in packet");
goto error;
}
rc = ssh_dh_import_next_pubkey_blob(session, pubkey_blob);
ssh_string_free(pubkey_blob);
if (rc != 0) {
goto error;
}
q_s_string = ssh_buffer_get_ssh_string(packet);
if (q_s_string == NULL) {
ssh_set_error(session,SSH_FATAL, "No Q_S ECC point in packet");
goto error;
}
session->next_crypto->ecdh_server_pubkey = q_s_string;
signature = ssh_buffer_get_ssh_string(packet);
if (signature == NULL) {
ssh_set_error(session, SSH_FATAL, "No signature in packet");
goto error;
}
session->next_crypto->dh_server_signature = signature;
signature=NULL; /* ownership changed */
/* TODO: verify signature now instead of waiting for NEWKEYS */
if (ecdh_build_k(session) < 0) {
ssh_set_error(session, SSH_FATAL, "Cannot build k number");
goto error;
}
/* Send the MSG_NEWKEYS */
if (ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
goto error;
}
rc=ssh_packet_send(session);
if (rc == SSH_ERROR) {
goto error;
}
SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
return SSH_PACKET_USED;
error:
session->session_state=SSH_SESSION_STATE_ERROR;
return SSH_PACKET_USED;
}
#endif /* HAVE_ECDH */
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