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+/*
+ * client.c - SSH client functions
+ *
+ * This file is part of the SSH Library
+ *
+ * Copyright (c) 2003-2008 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifndef _WIN32
+#include <arpa/inet.h>
+#endif
+
+#include "libssh/priv.h"
+#include "libssh/ssh2.h"
+#include "libssh/buffer.h"
+#include "libssh/packet.h"
+#include "libssh/socket.h"
+#include "libssh/session.h"
+#include "libssh/dh.h"
+
+#define set_status(session, status) do {\
+ if (session->callbacks && session->callbacks->connect_status_function) \
+ session->callbacks->connect_status_function(session->callbacks->userdata, status); \
+ } while (0)
+
+/**
+ * @internal
+ * @brief Callback to be called when the socket is connected or had a
+ * connection error. Changes the state of the session and updates the error
+ * message.
+ * @param code one of SSH_SOCKET_CONNECTED_OK or SSH_SOCKET_CONNECTED_ERROR
+ * @param user is a pointer to session
+ */
+static void socket_callback_connected(int code, int errno_code, void *user){
+ ssh_session session=(ssh_session)user;
+ enter_function();
+ ssh_log(session,SSH_LOG_RARE,"Socket connection callback: %d (%d)",code, errno_code);
+ if(code == SSH_SOCKET_CONNECTED_OK)
+ session->session_state=SSH_SESSION_STATE_SOCKET_CONNECTED;
+ else {
+ session->session_state=SSH_SESSION_STATE_ERROR;
+ ssh_set_error(session,SSH_FATAL,"%s",strerror(errno_code));
+ }
+ session->ssh_connection_callback(session);
+ leave_function();
+}
+
+/**
+ * @internal
+ *
+ * @brief Gets the banner from socket and saves it in session.
+ * Updates the session state
+ *
+ * @param data pointer to the beginning of header
+ * @param len size of the banner
+ * @param user is a pointer to session
+ * @returns Number of bytes processed, or zero if the banner is not complete.
+ */
+static int callback_receive_banner(const void *data, size_t len, void *user) {
+ char *buffer = (char *)data;
+ ssh_session session=(ssh_session) user;
+ char *str = NULL;
+ size_t i;
+ int ret=0;
+ enter_function();
+ for(i=0;i<len;++i){
+#ifdef WITH_PCAP
+ if(session->pcap_ctx && buffer[i] == '\n'){
+ ssh_pcap_context_write(session->pcap_ctx,SSH_PCAP_DIR_IN,buffer,i+1,i+1);
+ }
+#endif
+ if(buffer[i]=='\r')
+ buffer[i]='\0';
+ if(buffer[i]=='\n'){
+ buffer[i]='\0';
+ str=strdup(buffer);
+ /* number of bytes read */
+ ret=i+1;
+ session->serverbanner=str;
+ session->session_state=SSH_SESSION_STATE_BANNER_RECEIVED;
+ ssh_log(session,SSH_LOG_PACKET,"Received banner: %s",str);
+ session->ssh_connection_callback(session);
+ leave_function();
+ return ret;
+ }
+ if(i>127){
+ /* Too big banner */
+ session->session_state=SSH_SESSION_STATE_ERROR;
+ ssh_set_error(session,SSH_FATAL,"Receiving banner: too large banner");
+ leave_function();
+ return 0;
+ }
+ }
+ leave_function();
+ return ret;
+}
+
+/**
+ * @internal
+ *
+ * @brief Analyze the SSH banner to find out if we have a SSHv1 or SSHv2
+ * server.
+ *
+ * @param session The session to analyze the banner from.
+ * @param ssh1 The variable which is set if it is a SSHv1 server.
+ * @param ssh2 The variable which is set if it is a SSHv2 server.
+ *
+ * @return 0 on success, < 0 on error.
+ *
+ * @see ssh_get_banner()
+ */
+static int ssh_analyze_banner(ssh_session session, int *ssh1, int *ssh2) {
+ const char *banner = session->serverbanner;
+ const char *openssh;
+
+ ssh_log(session, SSH_LOG_RARE, "Analyzing banner: %s", banner);
+
+ if (strncmp(banner, "SSH-", 4) != 0) {
+ ssh_set_error(session, SSH_FATAL, "Protocol mismatch: %s", banner);
+ return -1;
+ }
+
+ /*
+ * Typical banners e.g. are:
+ * SSH-1.5-blah
+ * SSH-1.99-blah
+ * SSH-2.0-blah
+ */
+ switch(banner[4]) {
+ case '1':
+ *ssh1 = 1;
+ if (banner[6] == '9') {
+ *ssh2 = 1;
+ } else {
+ *ssh2 = 0;
+ }
+ break;
+ case '2':
+ *ssh1 = 0;
+ *ssh2 = 1;
+ break;
+ default:
+ ssh_set_error(session, SSH_FATAL, "Protocol mismatch: %s", banner);
+ return -1;
+ }
+
+ openssh = strstr(banner, "OpenSSH");
+ if (openssh != NULL) {
+ int major, minor;
+ major = strtol(openssh + 8, (char **) NULL, 10);
+ minor = strtol(openssh + 10, (char **) NULL, 10);
+ session->openssh = SSH_VERSION_INT(major, minor, 0);
+ ssh_log(session, SSH_LOG_RARE,
+ "We are talking to an OpenSSH server version: %d.%d (%x)",
+ major, minor, session->openssh);
+ }
+
+ return 0;
+}
+
+/** @internal
+ * @brief Sends a SSH banner to the server.
+ *
+ * @param session The SSH session to use.
+ *
+ * @param server Send client or server banner.
+ *
+ * @return 0 on success, < 0 on error.
+ */
+int ssh_send_banner(ssh_session session, int server) {
+ const char *banner = NULL;
+ char buffer[128] = {0};
+ int err=SSH_ERROR;
+
+ enter_function();
+
+ banner = session->version == 1 ? CLIENTBANNER1 : CLIENTBANNER2;
+
+ if (session->xbanner) {
+ banner = session->xbanner;
+ }
+
+ if (server) {
+ session->serverbanner = strdup(banner);
+ if (session->serverbanner == NULL) {
+ goto end;
+ }
+ } else {
+ session->clientbanner = strdup(banner);
+ if (session->clientbanner == NULL) {
+ goto end;
+ }
+ }
+
+ snprintf(buffer, 128, "%s\n", banner);
+
+ if (ssh_socket_write(session->socket, buffer, strlen(buffer)) == SSH_ERROR) {
+ goto end;
+ }
+ if (ssh_socket_nonblocking_flush(session->socket) == SSH_ERROR){
+ goto end;
+ }
+#ifdef WITH_PCAP
+ if(session->pcap_ctx)
+ ssh_pcap_context_write(session->pcap_ctx,SSH_PCAP_DIR_OUT,buffer,strlen(buffer),strlen(buffer));
+#endif
+ err=SSH_OK;
+end:
+ leave_function();
+ return err;
+}
+
+
+
+SSH_PACKET_CALLBACK(ssh_packet_dh_reply){
+ ssh_string f = NULL;
+ ssh_string pubkey = NULL;
+ ssh_string signature = NULL;
+ (void)type;
+ (void)user;
+ ssh_log(session,SSH_LOG_PROTOCOL,"Received SSH_KEXDH_REPLY");
+ if(session->session_state!= SSH_SESSION_STATE_DH &&
+ session->dh_handshake_state != DH_STATE_INIT_SENT){
+ ssh_set_error(session,SSH_FATAL,"ssh_packet_dh_reply called in wrong state : %d:%d",
+ session->session_state,session->dh_handshake_state);
+ goto error;
+ }
+
+ pubkey = buffer_get_ssh_string(packet);
+ if (pubkey == NULL){
+ ssh_set_error(session,SSH_FATAL, "No public key in packet");
+ goto error;
+ }
+ dh_import_pubkey(session, pubkey);
+
+ f = buffer_get_ssh_string(packet);
+ if (f == NULL) {
+ ssh_set_error(session,SSH_FATAL, "No F number in packet");
+ goto error;
+ }
+ if (dh_import_f(session, f) < 0) {
+ ssh_set_error(session, SSH_FATAL, "Cannot import f number");
+ goto error;
+ }
+ ssh_string_burn(f);
+ ssh_string_free(f);
+ f=NULL;
+ signature = buffer_get_ssh_string(packet);
+ if (signature == NULL) {
+ ssh_set_error(session, SSH_FATAL, "No signature in packet");
+ goto error;
+ }
+ session->dh_server_signature = signature;
+ signature=NULL; /* ownership changed */
+ if (dh_build_k(session) < 0) {
+ ssh_set_error(session, SSH_FATAL, "Cannot build k number");
+ goto error;
+ }
+
+ /* Send the MSG_NEWKEYS */
+ if (buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
+ goto error;
+ }
+
+ packet_send(session);
+ ssh_log(session, 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;
+}
+
+SSH_PACKET_CALLBACK(ssh_packet_newkeys){
+ ssh_string signature = NULL;
+ int rc;
+ (void)packet;
+ (void)user;
+ (void)type;
+ ssh_log(session, SSH_LOG_PROTOCOL, "Received SSH_MSG_NEWKEYS");
+ if(session->session_state!= SSH_SESSION_STATE_DH &&
+ session->dh_handshake_state != DH_STATE_NEWKEYS_SENT){
+ ssh_set_error(session,SSH_FATAL,"ssh_packet_newkeys called in wrong state : %d:%d",
+ session->session_state,session->dh_handshake_state);
+ goto error;
+ }
+ if(session->server){
+ /* server things are done in server.c */
+ session->dh_handshake_state=DH_STATE_FINISHED;
+ } else {
+ /* client */
+ rc = make_sessionid(session);
+ if (rc != SSH_OK) {
+ goto error;
+ }
+
+ /*
+ * Set the cryptographic functions for the next crypto
+ * (it is needed for generate_session_keys for key lengths)
+ */
+ if (crypt_set_algorithms(session)) {
+ goto error;
+ }
+
+ if (generate_session_keys(session) < 0) {
+ goto error;
+ }
+
+ /* Verify the host's signature. FIXME do it sooner */
+ signature = session->dh_server_signature;
+ session->dh_server_signature = NULL;
+ if (signature_verify(session, signature)) {
+ goto error;
+ }
+
+ /* forget it for now ... */
+ ssh_string_burn(signature);
+ ssh_string_free(signature);
+ signature=NULL;
+ /*
+ * Once we got SSH2_MSG_NEWKEYS we can switch next_crypto and
+ * current_crypto
+ */
+ if (session->current_crypto) {
+ crypto_free(session->current_crypto);
+ session->current_crypto=NULL;
+ }
+
+ /* FIXME later, include a function to change keys */
+ session->current_crypto = session->next_crypto;
+
+ session->next_crypto = crypto_new();
+ if (session->next_crypto == NULL) {
+ ssh_set_error_oom(session);
+ goto error;
+ }
+ }
+ session->dh_handshake_state = DH_STATE_FINISHED;
+ session->ssh_connection_callback(session);
+ return SSH_PACKET_USED;
+error:
+ session->session_state=SSH_SESSION_STATE_ERROR;
+ return SSH_PACKET_USED;
+}
+
+/** @internal
+ * @brief launches the DH handshake state machine
+ * @param session session handle
+ * @returns SSH_OK or SSH_ERROR
+ * @warning this function returning is no proof that DH handshake is
+ * completed
+ */
+static int dh_handshake(ssh_session session) {
+ ssh_string e = NULL;
+ ssh_string f = NULL;
+ ssh_string signature = NULL;
+ int rc = SSH_ERROR;
+
+ enter_function();
+
+ switch (session->dh_handshake_state) {
+ case DH_STATE_INIT:
+ if (buffer_add_u8(session->out_buffer, SSH2_MSG_KEXDH_INIT) < 0) {
+ goto error;
+ }
+
+ if (dh_generate_x(session) < 0) {
+ goto error;
+ }
+ if (dh_generate_e(session) < 0) {
+ goto error;
+ }
+
+ e = dh_get_e(session);
+ if (e == NULL) {
+ goto error;
+ }
+
+ if (buffer_add_ssh_string(session->out_buffer, e) < 0) {
+ goto error;
+ }
+ ssh_string_burn(e);
+ ssh_string_free(e);
+ e=NULL;
+
+ rc = packet_send(session);
+ if (rc == SSH_ERROR) {
+ goto error;
+ }
+
+ session->dh_handshake_state = DH_STATE_INIT_SENT;
+ case DH_STATE_INIT_SENT:
+ /* wait until ssh_packet_dh_reply is called */
+ break;
+ case DH_STATE_NEWKEYS_SENT:
+ /* wait until ssh_packet_newkeys is called */
+ break;
+ case DH_STATE_FINISHED:
+ leave_function();
+ return SSH_OK;
+ default:
+ ssh_set_error(session, SSH_FATAL, "Invalid state in dh_handshake(): %d",
+ session->dh_handshake_state);
+ leave_function();
+ return SSH_ERROR;
+ }
+
+ leave_function();
+ return SSH_AGAIN;
+error:
+ if(e != NULL){
+ ssh_string_burn(e);
+ ssh_string_free(e);
+ }
+ if(f != NULL){
+ ssh_string_burn(f);
+ ssh_string_free(f);
+ }
+ if(signature != NULL){
+ ssh_string_burn(signature);
+ ssh_string_free(signature);
+ }
+
+ leave_function();
+ return rc;
+}
+
+/**
+ * @internal
+ * @brief handles a SSH_SERVICE_ACCEPT packet
+ *
+ */
+SSH_PACKET_CALLBACK(ssh_packet_service_accept){
+ (void)packet;
+ (void)type;
+ (void)user;
+ enter_function();
+ session->auth_service_state=SSH_AUTH_SERVICE_ACCEPTED;
+ ssh_log(session, SSH_LOG_PACKET,
+ "Received SSH_MSG_SERVICE_ACCEPT");
+ leave_function();
+ return SSH_PACKET_USED;
+}
+
+/**
+ * @internal
+ *
+ * @brief Request a service from the SSH server.
+ *
+ * Service requests are for example: ssh-userauth, ssh-connection, etc.
+ *
+ * @param session The session to use to ask for a service request.
+ * @param service The service request.
+ *
+ * @return SSH_OK on success
+ * @return SSH_ERROR on error
+ * @return SSH_AGAIN No response received yet
+ * @bug actually only works with ssh-userauth
+ */
+int ssh_service_request(ssh_session session, const char *service) {
+ ssh_string service_s = NULL;
+ int rc=SSH_ERROR;
+ enter_function();
+ switch(session->auth_service_state){
+ case SSH_AUTH_SERVICE_NONE:
+ if (buffer_add_u8(session->out_buffer, SSH2_MSG_SERVICE_REQUEST) < 0) {
+ break;
+ }
+ service_s = ssh_string_from_char(service);
+ if (service_s == NULL) {
+ break;
+ }
+
+ if (buffer_add_ssh_string(session->out_buffer,service_s) < 0) {
+ ssh_string_free(service_s);
+ break;
+ }
+ ssh_string_free(service_s);
+
+ if (packet_send(session) == SSH_ERROR) {
+ ssh_set_error(session, SSH_FATAL,
+ "Sending SSH2_MSG_SERVICE_REQUEST failed.");
+ break;
+ }
+
+ ssh_log(session, SSH_LOG_PACKET,
+ "Sent SSH_MSG_SERVICE_REQUEST (service %s)", service);
+ session->auth_service_state=SSH_AUTH_SERVICE_SENT;
+ rc=SSH_AGAIN;
+ break;
+ case SSH_AUTH_SERVICE_DENIED:
+ ssh_set_error(session,SSH_FATAL,"ssh_auth_service request denied");
+ break;
+ case SSH_AUTH_SERVICE_ACCEPTED:
+ rc=SSH_OK;
+ break;
+ case SSH_AUTH_SERVICE_SENT:
+ rc=SSH_AGAIN;
+ break;
+ case SSH_AUTH_SERVICE_USER_SENT:
+ /* Invalid state, SSH1 specific */
+ rc=SSH_ERROR;
+ break;
+ }
+
+ leave_function();
+ return rc;
+}
+
+/**
+ * @addtogroup libssh_session
+ *
+ * @{
+ */
+
+/**
+ * @internal
+ *
+ * @brief A function to be called each time a step has been done in the
+ * connection.
+ */
+static void ssh_client_connection_callback(ssh_session session){
+ int ssh1,ssh2;
+ enter_function();
+ switch(session->session_state){
+ case SSH_SESSION_STATE_NONE:
+ case SSH_SESSION_STATE_CONNECTING:
+ case SSH_SESSION_STATE_SOCKET_CONNECTED:
+ break;
+ case SSH_SESSION_STATE_BANNER_RECEIVED:
+ if (session->serverbanner == NULL) {
+ goto error;
+ }
+ set_status(session, 0.4f);
+ ssh_log(session, SSH_LOG_RARE,
+ "SSH server banner: %s", session->serverbanner);
+
+ /* Here we analyze the different protocols the server allows. */
+ if (ssh_analyze_banner(session, &ssh1, &ssh2) < 0) {
+ goto error;
+ }
+ /* Here we decide which version of the protocol to use. */
+ if (ssh2 && session->ssh2) {
+ session->version = 2;
+ } else if(ssh1 && session->ssh1) {
+ session->version = 1;
+ } else if(ssh1 && !session->ssh1){
+#ifdef WITH_SSH1
+ ssh_set_error(session, SSH_FATAL,
+ "SSH-1 protocol not available (configure session to allow SSH-1)");
+ goto error;
+#else
+ ssh_set_error(session, SSH_FATAL,
+ "SSH-1 protocol not available (libssh compiled without SSH-1 support)");
+ goto error;
+#endif
+ } else {
+ ssh_set_error(session, SSH_FATAL,
+ "No version of SSH protocol usable (banner: %s)",
+ session->serverbanner);
+ goto error;
+ }
+ /* from now, the packet layer is handling incoming packets */
+ if(session->version==2)
+ session->socket_callbacks.data=ssh_packet_socket_callback;
+#ifdef WITH_SSH1
+ else
+ session->socket_callbacks.data=ssh_packet_socket_callback1;
+#endif
+ ssh_packet_set_default_callbacks(session);
+ ssh_send_banner(session, 0);
+ set_status(session, 0.5f);
+ session->session_state=SSH_SESSION_STATE_INITIAL_KEX;
+ break;
+ case SSH_SESSION_STATE_INITIAL_KEX:
+ /* TODO: This state should disappear in favor of get_key handle */
+#ifdef WITH_SSH1
+ if(session->version==1){
+ if (ssh_get_kex1(session) < 0)
+ goto error;
+ set_status(session,0.6f);
+ session->connected = 1;
+ break;
+ }
+#endif
+ break;
+ case SSH_SESSION_STATE_KEXINIT_RECEIVED:
+ set_status(session,0.6f);
+ ssh_list_kex(session, &session->server_kex);
+ if (set_kex(session) < 0) {
+ goto error;
+ }
+ if (ssh_send_kex(session, 0) < 0) {
+ goto error;
+ }
+ set_status(session,0.8f);
+ session->session_state=SSH_SESSION_STATE_DH;
+ if (dh_handshake(session) == SSH_ERROR) {
+ goto error;
+ }
+ case SSH_SESSION_STATE_DH:
+ if(session->dh_handshake_state==DH_STATE_FINISHED){
+ set_status(session,1.0f);
+ session->connected = 1;
+ session->session_state=SSH_SESSION_STATE_AUTHENTICATING;
+ }
+ break;
+ case SSH_SESSION_STATE_AUTHENTICATING:
+ break;
+ case SSH_SESSION_STATE_ERROR:
+ goto error;
+ default:
+ ssh_set_error(session,SSH_FATAL,"Invalid state %d",session->session_state);
+ }
+ leave_function();
+ return;
+ error:
+ ssh_socket_close(session->socket);
+ session->alive = 0;
+ session->session_state=SSH_SESSION_STATE_ERROR;
+ leave_function();
+}
+
+/**
+ * @brief Connect to the ssh server.
+ *
+ * @param[in] session The ssh session to connect.
+ *
+ * @returns SSH_OK on success, SSH_ERROR on error.
+ *
+ * @see ssh_new()
+ * @see ssh_disconnect()
+ */
+int ssh_connect(ssh_session session) {
+ int ret;
+
+ if (session == NULL) {
+ ssh_set_error(session, SSH_FATAL, "Invalid session pointer");
+ return SSH_ERROR;
+ }
+
+ enter_function();
+
+ session->alive = 0;
+ session->client = 1;
+
+ if (ssh_init() < 0) {
+ leave_function();
+ return SSH_ERROR;
+ }
+ if (session->fd == SSH_INVALID_SOCKET && session->host == NULL && session->ProxyCommand == NULL) {
+ ssh_set_error(session, SSH_FATAL, "Hostname required");
+ leave_function();
+ return SSH_ERROR;
+ }
+
+ ret = ssh_options_apply(session);
+ if (ret < 0) {
+ ssh_set_error(session, SSH_FATAL, "Couldn't apply options");
+ leave_function();
+ return SSH_ERROR;
+ }
+
+ session->ssh_connection_callback = ssh_client_connection_callback;
+ session->session_state=SSH_SESSION_STATE_CONNECTING;
+ ssh_socket_set_callbacks(session->socket,&session->socket_callbacks);
+ session->socket_callbacks.connected=socket_callback_connected;
+ session->socket_callbacks.data=callback_receive_banner;
+ session->socket_callbacks.exception=ssh_socket_exception_callback;
+ session->socket_callbacks.userdata=session;
+ if (session->fd != SSH_INVALID_SOCKET) {
+ ssh_socket_set_fd(session->socket, session->fd);
+ ret=SSH_OK;
+#ifndef _WIN32
+ } else if (session->ProxyCommand != NULL){
+ ret=ssh_socket_connect_proxycommand(session->socket, session->ProxyCommand);
+#endif
+ } else {
+ ret=ssh_socket_connect(session->socket, session->host, session->port,
+ session->bindaddr);
+
+ /*, session->timeout * 1000 + session->timeout_usec); */
+ }
+ if (ret == SSH_ERROR) {
+ leave_function();
+ return SSH_ERROR;
+ }
+
+ set_status(session, 0.2f);
+
+ session->alive = 1;
+ ssh_log(session,SSH_LOG_PROTOCOL,"Socket connecting, now waiting for the callbacks to work");
+ while(session->session_state != SSH_SESSION_STATE_ERROR &&
+ session->session_state != SSH_SESSION_STATE_AUTHENTICATING &&
+ session->session_state != SSH_SESSION_STATE_DISCONNECTED){
+ /* loop until SSH_SESSION_STATE_BANNER_RECEIVED or
+ * SSH_SESSION_STATE_ERROR */
+ ssh_handle_packets(session,-1);
+ ssh_log(session,SSH_LOG_PACKET,"ssh_connect: Actual state : %d",session->session_state);
+ }
+ leave_function();
+ if(session->session_state == SSH_SESSION_STATE_ERROR || session->session_state == SSH_SESSION_STATE_DISCONNECTED)
+ return SSH_ERROR;
+ return SSH_OK;
+}
+
+/**
+ * @brief Get the issue banner from the server.
+ *
+ * This is the banner showing a disclaimer to users who log in,
+ * typically their right or the fact that they will be monitored.
+ *
+ * @param[in] session The SSH session to use.
+ *
+ * @return A newly allocated string with the banner, NULL on error.
+ */
+char *ssh_get_issue_banner(ssh_session session) {
+ if (session == NULL || session->banner == NULL) {
+ return NULL;
+ }
+
+ return ssh_string_to_char(session->banner);
+}
+
+/**
+ * @brief Get the version of the OpenSSH server, if it is not an OpenSSH server
+ * then 0 will be returned.
+ *
+ * You can use the SSH_VERSION_INT macro to compare version numbers.
+ *
+ * @param[in] session The SSH session to use.
+ *
+ * @return The version number if available, 0 otherwise.
+ */
+int ssh_get_openssh_version(ssh_session session) {
+ if (session == NULL) {
+ return 0;
+ }
+
+ return session->openssh;
+}
+
+/**
+ * @brief Disconnect from a session (client or server).
+ * The session can then be reused to open a new session.
+ *
+ * @param[in] session The SSH session to use.
+ */
+void ssh_disconnect(ssh_session session) {
+ ssh_string str = NULL;
+
+ if (session == NULL) {
+ return;
+ }
+
+ enter_function();
+
+ if (ssh_socket_is_open(session->socket)) {
+ if (buffer_add_u8(session->out_buffer, SSH2_MSG_DISCONNECT) < 0) {
+ goto error;
+ }
+ if (buffer_add_u32(session->out_buffer,
+ htonl(SSH2_DISCONNECT_BY_APPLICATION)) < 0) {
+ goto error;
+ }
+
+ str = ssh_string_from_char("Bye Bye");
+ if (str == NULL) {
+ goto error;
+ }
+
+ if (buffer_add_ssh_string(session->out_buffer,str) < 0) {
+ ssh_string_free(str);
+ goto error;
+ }
+ ssh_string_free(str);
+
+ packet_send(session);
+ ssh_socket_close(session->socket);
+ }
+ session->alive = 0;
+
+error:
+ leave_function();
+}
+
+const char *ssh_copyright(void) {
+ return SSH_STRINGIFY(LIBSSH_VERSION) " (c) 2003-2010 Aris Adamantiadis "
+ "(aris@0xbadc0de.be) Distributed under the LGPL, please refer to COPYING"
+ "file for information about your rights";
+}
+/** @} */
+
+/* vim: set ts=4 sw=4 et cindent: */