diff --git a/include/libssh/callbacks.h b/include/libssh/callbacks.h index 8804370b..a838bdce 100644 --- a/include/libssh/callbacks.h +++ b/include/libssh/callbacks.h @@ -540,6 +540,37 @@ typedef int (*ssh_channel_pty_window_change_callback) (ssh_session session, int pxwidth, int pwheight, void *userdata); +/** + * @brief SSH channel Exec request from a client. + * @param channel the channel + * @param command the shell command to be executed + * @param userdata Userdata to be passed to the callback function. + * @returns 0 if the exec request is accepted + * @returns 1 if the request is denied + */ +typedef int (*ssh_channel_exec_request_callback) (ssh_session session, + ssh_channel channel, + const char *command, + void *userdata); + +/** + * @brief SSH channel environment request from a client. + * @param channel the channel + * @param env_name name of the environment value to be set + * @param env_value value of the environment value to be set + * @param userdata Userdata to be passed to the callback function. + * @returns 0 if the env request is accepted + * @returns 1 if the request is denied + * @warning some environment variables can be dangerous if changed (e.g. + * LD_PRELOAD) and should not be fulfilled. + */ +typedef int (*ssh_channel_env_request_callback) (ssh_session session, + ssh_channel channel, + const char *env_name, + const char *env_value, + void *userdata); + + struct ssh_channel_callbacks_struct { /** DON'T SET THIS use ssh_callbacks_init() instead. */ size_t size; @@ -591,8 +622,16 @@ struct ssh_channel_callbacks_struct { * window change. */ ssh_channel_pty_window_change_callback channel_pty_window_change_function; - + /** This function will be called when a client requests a + * command execution. + */ + ssh_channel_exec_request_callback channel_exec_request_function; + /** This function will be called when a client requests an environment + * variable to be set. + */ + ssh_channel_env_request_callback channel_env_request_function; }; + typedef struct ssh_channel_callbacks_struct *ssh_channel_callbacks; /** diff --git a/src/messages.c b/src/messages.c index 4e550567..450b3236 100644 --- a/src/messages.c +++ b/src/messages.c @@ -176,6 +176,28 @@ static int ssh_execute_server_callbacks(ssh_session session, ssh_message msg){ msg->channel_request.pxheight, msg->channel_request.pxwidth, channel->callbacks->userdata); } + } else if(msg->channel_request.type == SSH_CHANNEL_REQUEST_EXEC ){ + if(ssh_callbacks_exists(channel->callbacks, channel_exec_request_function)){ + rc = channel->callbacks->channel_exec_request_function(session, channel, + msg->channel_request.command, + channel->callbacks->userdata); + if(rc == 0) + ssh_message_channel_request_reply_success(msg); + else + ssh_message_reply_default(msg); + return SSH_OK; + } + } else if(msg->channel_request.type == SSH_CHANNEL_REQUEST_ENV){ + if(ssh_callbacks_exists(channel->callbacks, channel_env_request_function)){ + rc = channel->callbacks->channel_env_request_function(session, channel, + msg->channel_request.var_name, msg->channel_request.var_value, + channel->callbacks->userdata); + if(rc == 0) + ssh_message_channel_request_reply_success(msg); + else + ssh_message_reply_default(msg); + return SSH_OK; + } } break; case SSH_REQUEST_SERVICE: