/* * This file is part of the SSH Library * * Copyright (c) 2009 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. */ /* callback.h * This file includes the public declarations for the libssh callback mechanism */ #ifndef _SSH_CALLBACK_H #define _SSH_CALLBACK_H #include #include #ifdef __cplusplus extern "C" { #endif /** @internal * @brief callback to process simple codes * @param code value to transmit * @param user Userdata to pass in callback */ typedef void (*ssh_callback_int) (int code, void *user); /** @internal * @brief callback for data received messages. * @param data data retrieved from the socket or stream * @param len number of bytes available from this stream * @param user user-supplied pointer sent along with all callback messages * @returns number of bytes processed by the callee. The remaining bytes will * be sent in the next callback message, when more data is available. */ typedef int (*ssh_callback_data) (const void *data, size_t len, void *user); typedef void (*ssh_callback_int_int) (int code, int errno_code, void *user); typedef int (*ssh_message_callback) (ssh_session, ssh_message message, void *user); typedef int (*ssh_channel_callback_int) (ssh_channel channel, int code, void *user); typedef int (*ssh_channel_callback_data) (ssh_channel channel, int code, void *data, size_t len, void *user); /** * @brief SSH authentication callback. * * @param prompt Prompt to be displayed. * @param buf Buffer to save the password. You should null-terminate it. * @param len Length of the buffer. * @param echo Enable or disable the echo of what you type. * @param verify Should the password be verified? * @param userdata Userdata to be passed to the callback function. Useful * for GUI applications. * * @return 0 on success, < 0 on error. */ typedef int (*ssh_auth_callback) (const char *prompt, char *buf, size_t len, int echo, int verify, void *userdata); /** * @brief SSH log callback. All logging messages will go through this callback * @param session Current session handler * @param priority Priority of the log, the smaller being the more important * @param message the actual message * @param userdata Userdata to be passed to the callback function. */ typedef void (*ssh_log_callback) (ssh_session session, int priority, const char *message, void *userdata); /** * @brief SSH Connection status callback. * @param session Current session handler * @param status Percentage of connection status, going from 0.0 to 1.0 * once connection is done. * @param userdata Userdata to be passed to the callback function. */ typedef void (*ssh_status_callback) (ssh_session session, float status, void *userdata); /** * The structure to replace libssh functions with appropriate callbacks. */ struct ssh_callbacks_struct { /** DON'T SET THIS use ssh_callbacks_init() instead. */ size_t size; /** * User-provided data. User is free to set anything he wants here */ void *userdata; /** * This functions will be called if e.g. a keyphrase is needed. */ ssh_auth_callback auth_function; /** * This function will be called each time a loggable event happens. */ ssh_log_callback log_function; /** * This function gets called during connection time to indicate the * percentage of connection steps completed. */ void (*connect_status_function)(void *userdata, float status); }; typedef struct ssh_callbacks_struct *ssh_callbacks; /** * These are the callbacks exported by the socket structure * They are called by the socket module when a socket event appears */ struct ssh_socket_callbacks_struct { /** * User-provided data. User is free to set anything he wants here */ void *userdata; /** * This function will be called each time data appears on socket. The data * not consumed will appear on the next data event. */ ssh_callback_data data; /** This function will be called each time a controlflow state changes, i.e. * the socket is available for reading or writing. */ ssh_callback_int controlflow; /** This function will be called each time an exception appears on socket. An * exception can be a socket problem (timeout, ...) or an end-of-file. */ ssh_callback_int_int exception; /** This function is called when the ssh_socket_connect was used on the socket * on nonblocking state, and the connection successed. */ ssh_callback_int_int connected; }; typedef struct ssh_socket_callbacks_struct *ssh_socket_callbacks; #define SSH_SOCKET_FLOW_WRITEWILLBLOCK 1 #define SSH_SOCKET_FLOW_WRITEWONTBLOCK 2 #define SSH_SOCKET_EXCEPTION_EOF 1 #define SSH_SOCKET_EXCEPTION_ERROR 2 #define SSH_SOCKET_CONNECTED_OK 1 #define SSH_SOCKET_CONNECTED_ERROR 2 #define SSH_SOCKET_CONNECTED_TIMEOUT 3 /** Initializes an ssh_callbacks_struct * A call to this macro is mandatory when you have set a new * ssh_callback_struct structure. Its goal is to maintain the binary * compatibility with future versions of libssh as the structure * evolves with time. */ #define ssh_callbacks_init(p) do {\ (p)->size=sizeof(*(p)); \ } while(0); /** @brief Prototype for a packet callback, to be called when a new packet arrives * @param session The current session of the packet * @param type packet type (see ssh2.h) * @param packet buffer containing the packet, excluding size, type and padding fields * @param user user argument to the callback * and are called each time a packet shows up * @returns SSH_PACKET_USED Packet was parsed and used * @returns SSH_PACKET_NOT_USED Packet was not used or understood, processing must continue */ typedef int (*ssh_packet_callback) (ssh_session session, uint8_t type, ssh_buffer packet, void *user); /** return values for a ssh_packet_callback */ /** Packet was used and should not be parsed by another callback */ #define SSH_PACKET_USED 1 /** Packet was not used and should be passed to any other callback * available */ #define SSH_PACKET_NOT_USED 2 /** @brief This macro declares a packet callback handler * @code * SSH_PACKET_CALLBACK(mycallback){ * ... * } * @endcode */ #define SSH_PACKET_CALLBACK(name) \ int name (ssh_session session, uint8_t type, ssh_buffer packet, void *user) struct ssh_packet_callbacks_struct { /** Index of the first packet type being handled */ uint8_t start; /** Number of packets being handled by this callback struct */ uint8_t n_callbacks; /** A pointer to n_callbacks packet callbacks */ ssh_packet_callback *callbacks; /** * User-provided data. User is free to set anything he wants here */ void *user; }; typedef struct ssh_packet_callbacks_struct *ssh_packet_callbacks; /** * @brief Set the callback functions. * * This functions sets the callback structure to use your own callback * functions for auth, logging and status. * * @code * struct ssh_callbacks_struct cb; * memset(&cb, 0, sizeof(struct ssh_callbacks_struct)); * cb.userdata = data; * cb.auth_function = my_auth_function; * * ssh_callbacks_init(&cb); * ssh_set_callbacks(session, &cb); * @endcode * * @param session The session to set the callback structure. * * @param cb The callback itself. * * @return 0 on success, < 0 on error. */ LIBSSH_API int ssh_set_callbacks(ssh_session session, ssh_callbacks cb); #ifdef __cplusplus } #endif #endif /*_SSH_CALLBACK_H */