From 30fede7ecea2ccffdd5d6c6d02ba5d5454a3348f Mon Sep 17 00:00:00 2001 From: Joseph Southwell Date: Tue, 23 May 2017 17:32:41 -0400 Subject: [PATCH 1/3] got external io working in libssh client Signed-off-by: Joseph Southwell --- include/libssh/callbacks.h | 69 +++++++++++++++++++++++++ include/libssh/libsshpp.hpp | 8 +-- include/libssh/session.h | 5 +- src/callbacks.c | 17 +++++++ src/client.c | 1 + src/socket.c | 22 +++++++- 6 files changed, 101 insertions(+), 21 deletions(-) diff --git a/include/libssh/callbacks.h b/include/libssh/callbacks.h index 4e71b3b9..b382acb3 100644 --- a/include/libssh/callbacks.h +++ b/include/libssh/callbacks.h @@ -400,6 +400,52 @@ struct ssh_socket_callbacks_struct { }; typedef struct ssh_socket_callbacks_struct *ssh_socket_callbacks; +/** +* @brief callback to read data from the socket +* If this function returns less than zero +* it must update WSASetLastError or errno +* @param socket_t to read from +* @param userdata for callback +* @param buffer for read data +* @param size of read buffer +* @return < 0 on error and >= 0 indicated how much data read into buffer +*/ +typedef int(*ssh_callback_recv) (socket_t socket, void *userdata, char *buffer, int size); + +/** +* @brief callback to write data to the socket +* If this function returns less than zero +* it must update WSASetLastError or errno +* @param socket_t to write to +* @param userdata for callback +* @param buffer to write from +* @param size how much data to write +* @return < 0 on error and >= 0 indicated how much data consumed from buffer +*/ +typedef int(*ssh_callback_send) (socket_t socket, void *userdata, const char *buffer, int size); + +/** +* These are the callbacks exported by the socket structure +* They are called by unbuffered read and write when socket data is sent or received +*/ +struct ssh_socket_io_callbacks_struct { + /** + * User-provided data. User is free to set anything he wants here + */ + void *userdata; + /** + * This function will be called to write data to the socket. + * The data not consumed will appear on the next send event. + */ + ssh_callback_send send; + /** + * This function will be called to read data from the socket. + */ + ssh_callback_recv recv; +}; + +typedef struct ssh_socket_io_callbacks_struct *ssh_socket_io_callbacks; + #define SSH_SOCKET_FLOW_WRITEWILLBLOCK 1 #define SSH_SOCKET_FLOW_WRITEWONTBLOCK 2 @@ -566,6 +612,29 @@ typedef struct ssh_packet_callbacks_struct *ssh_packet_callbacks; LIBSSH_API int ssh_set_callbacks(ssh_session session, ssh_callbacks cb); /** +* @brief Set the session io callback functions. +* +* This functions sets the session io callback functions +* It allows you to use your own custom network interactions +* +* @code +* struct ssh_socket_io_callbacks_struct io_cb = { +* .userdata = data, +* .send = my_send_function +* .recv = my_recv_function +* }; +* ssh_set_io_callbacks(session, &io_cb); +* @endcode +* +* @param session The session to set the callback structure. +* +* @param io_cb The callback structure itself. +* +* @return SSH_OK on success, SSH_ERROR on error. +*/ +LIBSSH_API int ssh_set_io_callbacks(ssh_session session, ssh_socket_io_callbacks cb); + +/** * @brief SSH channel data callback. Called when data is available on a channel * @param session Current session handler * @param channel the actual channel diff --git a/include/libssh/libsshpp.hpp b/include/libssh/libsshpp.hpp index af08a914..1b058ad1 100644 --- a/include/libssh/libsshpp.hpp +++ b/include/libssh/libsshpp.hpp @@ -86,14 +86,14 @@ public: * @returns SSH_REQUEST_DENIED Request was denied by remote host * @see ssh_get_error_code */ - int getCode(){ + int getCode() const { return code; } /** @brief returns the error message of the last exception * @returns pointer to a c string containing the description of error * @see ssh_get_error */ - std::string getError(){ + std::string getError() const { return description; } private: @@ -378,7 +378,7 @@ public: return_throwable; } -private: +protected: ssh_session c_session; ssh_session getCSession(){ return c_session; @@ -584,7 +584,7 @@ public: ssh_throw(ret); return ret; } -private: +protected: ssh_session getCSession(){ return session->getCSession(); } diff --git a/include/libssh/session.h b/include/libssh/session.h index 60d78578..50a05b31 100644 --- a/include/libssh/session.h +++ b/include/libssh/session.h @@ -169,8 +169,9 @@ struct ssh_session_struct { void (*ssh_connection_callback)( struct ssh_session_struct *session); struct ssh_packet_callbacks_struct default_packet_callbacks; struct ssh_list *packet_callbacks; - struct ssh_socket_callbacks_struct socket_callbacks; - ssh_poll_ctx default_poll_ctx; + struct ssh_socket_callbacks_struct socket_callbacks; + struct ssh_socket_io_callbacks_struct socket_io_callbacks; + ssh_poll_ctx default_poll_ctx; /* options */ #ifdef WITH_PCAP ssh_pcap_context pcap_ctx; /* pcap debugging context */ diff --git a/src/callbacks.c b/src/callbacks.c index 3ed2f11c..c8ee9e7b 100644 --- a/src/callbacks.c +++ b/src/callbacks.c @@ -67,6 +67,23 @@ int ssh_set_callbacks(ssh_session session, ssh_callbacks cb) { return 0; } +int ssh_set_io_callbacks(ssh_session session, ssh_socket_io_callbacks io_cb) { + if (session == NULL ) { + return SSH_ERROR; + } + + if (io_cb == NULL) { + ssh_set_error(session, + SSH_FATAL, + "Invalid callback passed in (badly initialized)"); + return SSH_ERROR; + }; + + session->socket_io_callbacks = *io_cb; + return SSH_OK; +} + + static int ssh_add_set_channel_callbacks(ssh_channel channel, ssh_channel_callbacks cb, int prepend) diff --git a/src/client.c b/src/client.c index 3b120bbc..7c903403 100644 --- a/src/client.c +++ b/src/client.c @@ -576,6 +576,7 @@ int ssh_connect(ssh_session session) { session->socket_callbacks.userdata=session; if (session->opts.fd != SSH_INVALID_SOCKET) { session->session_state=SSH_SESSION_STATE_SOCKET_CONNECTED; + ssh_socket_set_io_callbacks(session->socket, &session->socket_io_callbacks); ssh_socket_set_fd(session->socket, session->opts.fd); ret=SSH_OK; #ifndef _WIN32 diff --git a/src/socket.c b/src/socket.c index 76dc55e5..b6af36af 100644 --- a/src/socket.c +++ b/src/socket.c @@ -87,6 +87,7 @@ struct ssh_socket_struct { ssh_buffer in_buffer; ssh_session session; ssh_socket_callbacks callbacks; + ssh_socket_io_callbacks io_callbacks; ssh_poll_handle poll_in; ssh_poll_handle poll_out; }; @@ -204,6 +205,19 @@ void ssh_socket_set_callbacks(ssh_socket s, ssh_socket_callbacks callbacks){ } /** +* @internal +* @brief the socket io callbacks, i.e. the callbacks to called +* to read or write data to the socket. +* Only useful when using an externally provided socket fd +* @param s socket to set callbacks on. +* @param callbacks a ssh_socket_io_callback object reference. +*/ + +void ssh_socket_set_io_callbacks(ssh_socket s, ssh_socket_io_callbacks io_callbacks) { + s->io_callbacks = io_callbacks; +} + +/** * @brief SSH poll callback. This callback will be used when an event * caught on the socket. * @@ -530,7 +544,9 @@ static int ssh_socket_unbuffered_read(ssh_socket s, void *buffer, uint32_t len) if (s->data_except) { return -1; } - if(s->fd_is_socket) + if (s->io_callbacks && s->io_callbacks->recv) + rc = s->io_callbacks->recv(s->fd_in, s->io_callbacks->userdata, buffer, len); + else if(s->fd_is_socket) rc = recv(s->fd_in,buffer, len, 0); else rc = read(s->fd_in,buffer, len); @@ -558,7 +574,9 @@ static int ssh_socket_unbuffered_write(ssh_socket s, const void *buffer, if (s->data_except) { return -1; } - if (s->fd_is_socket) + if (s->io_callbacks && s->io_callbacks->send) + w = s->io_callbacks->send(s->fd_in, s->io_callbacks->userdata, buffer, len); + else if (s->fd_is_socket) w = send(s->fd_out,buffer, len, 0); else w = write(s->fd_out, buffer, len); -- 2.11.0.windows.3