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session.c
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session.c
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/* Copyright (c) 2004-2006, Sara Golemon <sarag@libssh2.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms,
* with or without modification, are permitted provided
* that the following conditions are met:
*
* Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* Neither the name of the copyright holder nor the names
* of any other contributors may be used to endorse or
* promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*/
#include "libssh2_priv.h"
#include <errno.h>
#ifndef WIN32
#include <unistd.h>
#endif
#include <stdlib.h>
#ifdef HAVE_GETTIMEOFDAY
#include <sys/time.h>
#include <math.h>
#endif
#ifdef HAVE_POLL
# include <sys/poll.h>
#else
# ifdef HAVE_SELECT
# ifdef HAVE_SYS_SELECT_H
# include <sys/select.h>
# else
# include <sys/time.h>
# include <sys/types.h>
# endif
# endif
#endif
/* {{{ libssh2_default_alloc
*/
static LIBSSH2_ALLOC_FUNC(libssh2_default_alloc)
{
return malloc(count);
}
/* }}} */
/* {{{ libssh2_default_free
*/
static LIBSSH2_FREE_FUNC(libssh2_default_free)
{
free(ptr);
}
/* }}} */
/* {{{ libssh2_default_realloc
*/
static LIBSSH2_REALLOC_FUNC(libssh2_default_realloc)
{
return realloc(ptr, count);
}
/* }}} */
/* {{{ libssh2_default_write
*/
static LIBSSH2_WRITE_FUNC(libssh2_default_write)
{
return send(session->socket_fd, buffer, length, LIBSSH2_SOCKET_SEND_FLAGS(session));
}
static LIBSSH2_READ_FUNC(libssh2_default_read)
{
return recv(session->socket_fd, buffer, length, LIBSSH2_SOCKET_RECV_FLAGS(session));
}
/* {{{ libssh2_session_set_user_info
* ui is passed into the custom read / write functions
*/
LIBSSH2_API void libssh2_session_set_user_info(LIBSSH2_SESSION *session, void *ui)
{
session->userInfo = ui;
}
/* }}} */
/* {{{ libssh2_session_set_write
* Set a custom function to handle the writing to the socket/stream
*/
LIBSSH2_API void libssh2_session_set_write(LIBSSH2_SESSION *session, void *my_write)
{
session->ssh_write = my_write;
}
/* }}} */
/* {{{ libssh2_session_set_read
* Set a custom function to handle the reading from the socket/stream
*/
LIBSSH2_API void libssh2_session_set_read(LIBSSH2_SESSION *session, void *my_read)
{
session->ssh_read = my_read;
}
/* }}} */
/* {{{ libssh2_banner_receive
* Wait for a hello from the remote host
* Allocate a buffer and store the banner in session->remote.banner
* Returns: 0 on success, 1 on failure
*/
static int libssh2_banner_receive(LIBSSH2_SESSION *session)
{
char banner[256];
int banner_len = 0;
//unused int tries = 10;
while ((banner_len < sizeof(banner)) &&
((banner_len == 0) || (banner[banner_len-1] != '\n'))) {
char c = '\0';
int ret;
ret = LIBSSH2_READ(session, &c, 1);
if (ret < 0) {
#ifdef WIN32
switch (WSAGetLastError()) {
case WSAEWOULDBLOCK:
errno = EAGAIN;
break;
case WSAENOTSOCK:
errno = EBADF;
break;
case WSAENOTCONN:
case WSAECONNABORTED:
errno = ENOTCONN;
break;
case WSAEINTR:
errno = EINTR;
break;
}
#endif /* WIN32 */
if (errno != EAGAIN) {
/* Some kinda error, but don't break for non-blocking issues */
return 1;
}
}
if (ret <= 0) continue;
if (c == '\0') {
/* NULLs are not allowed in SSH banners */
return 1;
}
banner[banner_len++] = c;
}
while (banner_len &&
((banner[banner_len-1] == '\n') || (banner[banner_len-1] == '\r'))) {
banner_len--;
}
if (!banner_len)
return 1;
session->remote.banner = LIBSSH2_ALLOC(session, banner_len + 1);
memcpy(session->remote.banner, banner, banner_len);
session->remote.banner[banner_len] = '\0';
#ifdef LIBSSH2_DEBUG_TRANSPORT
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "Received Banner: %s", session->remote.banner);
#endif
return 0;
}
/* }}} */
/* {{{ libssh2_banner_send
* Send the default banner, or the one set via libssh2_setopt_string
*/
static int libssh2_banner_send(LIBSSH2_SESSION *session)
{
char *banner = LIBSSH2_SSH_DEFAULT_BANNER_WITH_CRLF;
int banner_len = sizeof(LIBSSH2_SSH_DEFAULT_BANNER_WITH_CRLF) - 1;
if (session->local.banner) {
/* setopt_string will have given us our \r\n characters */
banner_len = strlen((const char *)session->local.banner);
banner = (char *)session->local.banner;
}
#ifdef LIBSSH2_DEBUG_TRANSPORT
{
/* Hack and slash to avoid sending CRLF in debug output */
char banner_dup[256];
if (banner_len < 256) {
memcpy(banner_dup, banner, banner_len - 2);
banner_dup[banner_len - 2] = '\0';
} else {
memcpy(banner_dup, banner, 255);
banner[255] = '\0';
}
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "Sending Banner: %s", banner_dup);
}
#endif
return (LIBSSH2_WRITE(session, banner, banner_len) == banner_len) ? 0 : 1;
}
/* }}} */
/* {{{ libssh2_banner_set
* Set the local banner
*/
LIBSSH2_API int libssh2_banner_set(LIBSSH2_SESSION *session, const char *banner)
{
int banner_len = banner ? strlen(banner) : 0;
if (session->local.banner) {
LIBSSH2_FREE(session, session->local.banner);
session->local.banner = NULL;
}
if (!banner_len) {
return 0;
}
session->local.banner = LIBSSH2_ALLOC(session, banner_len + 3);
if (!session->local.banner) {
libssh2_error(session, LIBSSH2_ERROR_ALLOC, "Unable to allocate memory for local banner", 0);
return -1;
}
memcpy(session->local.banner, banner, banner_len);
#ifdef LIBSSH2_DEBUG_TRANSPORT
session->local.banner[banner_len] = '\0';
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "Setting local Banner: %s", session->local.banner);
#endif
session->local.banner[banner_len++] = '\r';
session->local.banner[banner_len++] = '\n';
session->local.banner[banner_len++] = '\0';
return 0;
}
/* }}} */
/* {{{ proto libssh2_session_init
* Allocate and initialize a libssh2 session structure
* Allows for malloc callbacks in case the calling program has its own memory manager
* It's allowable (but unadvisable) to define some but not all of the malloc callbacks
* An additional pointer value may be optionally passed to be sent to the callbacks (so they know who's asking)
*/
LIBSSH2_API LIBSSH2_SESSION *libssh2_session_init_ex(
LIBSSH2_ALLOC_FUNC((*my_alloc)),
LIBSSH2_FREE_FUNC((*my_free)),
LIBSSH2_REALLOC_FUNC((*my_realloc)),
void *abstract)
{
LIBSSH2_ALLOC_FUNC((*local_alloc)) = libssh2_default_alloc;
LIBSSH2_FREE_FUNC((*local_free)) = libssh2_default_free;
LIBSSH2_REALLOC_FUNC((*local_realloc)) = libssh2_default_realloc;
LIBSSH2_WRITE_FUNC((*local_write)) = libssh2_default_write;
LIBSSH2_READ_FUNC((*local_read)) = libssh2_default_read;
LIBSSH2_SESSION *session;
if (my_alloc) local_alloc = my_alloc;
if (my_free) local_free = my_free;
if (my_realloc) local_realloc = my_realloc;
session = local_alloc(sizeof(LIBSSH2_SESSION), abstract);
memset(session, 0, sizeof(LIBSSH2_SESSION));
session->alloc = local_alloc;
session->free = local_free;
session->realloc = local_realloc;
session->abstract = abstract;
session->ssh_write = local_write;
session->ssh_read = local_read;
#ifdef LIBSSH2_DEBUG_TRANSPORT
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "New session resource allocated");
#endif
libssh2_crypto_init ();
return session;
}
/* }}} */
/* {{{ libssh2_session_callback_set
* Set (or reset) a callback function
* Returns the prior address
*/
LIBSSH2_API void* libssh2_session_callback_set(LIBSSH2_SESSION *session, int cbtype, void *callback)
{
void *oldcb;
switch (cbtype) {
case LIBSSH2_CALLBACK_IGNORE:
oldcb = session->ssh_msg_ignore;
session->ssh_msg_ignore = callback;
return oldcb;
break;
case LIBSSH2_CALLBACK_DEBUG:
oldcb = session->ssh_msg_debug;
session->ssh_msg_debug = callback;
return oldcb;
break;
case LIBSSH2_CALLBACK_DISCONNECT:
oldcb = session->ssh_msg_disconnect;
session->ssh_msg_disconnect = callback;
return oldcb;
break;
case LIBSSH2_CALLBACK_MACERROR:
oldcb = session->macerror;
session->macerror = callback;
return oldcb;
break;
case LIBSSH2_CALLBACK_X11:
oldcb = session->x11;
session->x11 = callback;
return oldcb;
break;
}
#ifdef LIBSSH2_DEBUG_TRANSPORT
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "Setting Callback %d", cbtype);
#endif
return NULL;
}
/* }}} */
/* {{{ proto libssh2_session_startup
* session: LIBSSH2_SESSION struct allocated and owned by the calling program
* Returns: 0 on success, or non-zero on failure
* Any memory allocated by libssh2 will use alloc/realloc/free callbacks in session
* socket *must* be populated with an opened socket
*/
LIBSSH2_API int libssh2_session_startup(LIBSSH2_SESSION *session, int socket)
{
unsigned char *data;
unsigned long data_len;
unsigned char service[sizeof("ssh-userauth") + 5 - 1];
unsigned long service_length;
#ifdef LIBSSH2_DEBUG_TRANSPORT
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "session_startup for socket %d", socket);
#endif
if (socket < 0) {
/* Did we forget something? */
libssh2_error(session, LIBSSH2_ERROR_SOCKET_NONE, "Bad socket provided", 0);
return LIBSSH2_ERROR_SOCKET_NONE;
}
session->socket_fd = socket;
/* TODO: Liveness check */
if (libssh2_banner_send(session)) {
/* Unable to send banner? */
libssh2_error(session, LIBSSH2_ERROR_BANNER_SEND, "Error sending banner to remote host", 0);
return LIBSSH2_ERROR_BANNER_SEND;
}
if (libssh2_banner_receive(session)) {
/* Unable to receive banner from remote */
libssh2_error(session, LIBSSH2_ERROR_BANNER_NONE, "Timeout waiting for banner", 0);
return LIBSSH2_ERROR_BANNER_NONE;
}
if (libssh2_kex_exchange(session, 0)) {
libssh2_error(session, LIBSSH2_ERROR_KEX_FAILURE, "Unable to exchange encryption keys", 0);
return LIBSSH2_ERROR_KEX_FAILURE;
}
#ifdef LIBSSH2_DEBUG_TRANSPORT
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "Requesting userauth service");
#endif
/* Request the userauth service */
service[0] = SSH_MSG_SERVICE_REQUEST;
libssh2_htonu32(service + 1, sizeof("ssh-userauth") - 1);
memcpy(service + 5, "ssh-userauth", sizeof("ssh-userauth") - 1);
if (libssh2_packet_write(session, service, sizeof("ssh-userauth") + 5 - 1)) {
libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND, "Unable to ask for ssh-userauth service", 0);
return LIBSSH2_ERROR_SOCKET_SEND;
}
if (libssh2_packet_require(session, SSH_MSG_SERVICE_ACCEPT, &data, &data_len)) {
return LIBSSH2_ERROR_SOCKET_DISCONNECT;
}
service_length = libssh2_ntohu32(data + 1);
if ((service_length != (sizeof("ssh-userauth") - 1)) ||
strncmp("ssh-userauth", (const char *)data + 5, service_length)) {
LIBSSH2_FREE(session, data);
libssh2_error(session, LIBSSH2_ERROR_PROTO, "Invalid response received from server", 0);
return LIBSSH2_ERROR_PROTO;
}
LIBSSH2_FREE(session, data);
return 0;
}
/* }}} */
/* {{{ proto libssh2_session_free
* Frees the memory allocated to the session
* Also closes and frees any channels attached to this session
*/
LIBSSH2_API void libssh2_session_free(LIBSSH2_SESSION *session)
{
#ifdef LIBSSH2_DEBUG_TRANSPORT
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "Freeing session resource", session->remote.banner);
#endif
while (session->channels.head) {
LIBSSH2_CHANNEL *tmp = session->channels.head;
libssh2_channel_free(session->channels.head);
if (tmp == session->channels.head) {
/* channel_free couldn't do it's job, perform a messy cleanup */
tmp = session->channels.head;
/* unlink */
session->channels.head = tmp->next;
/* free */
LIBSSH2_FREE(session, tmp);
/* reverse linking isn't important here, we're killing the structure */
}
}
while (session->listeners) {
libssh2_channel_forward_cancel(session->listeners);
}
if (session->state & LIBSSH2_STATE_NEWKEYS) {
/* hostkey */
if (session->hostkey && session->hostkey->dtor) {
session->hostkey->dtor(session, &session->server_hostkey_abstract);
}
/* Client to Server */
/* crypt */
if (session->local.crypt && session->local.crypt->dtor) {
session->local.crypt->dtor(session, &session->local.crypt_abstract);
}
/* comp */
if (session->local.comp && session->local.comp->dtor) {
session->local.comp->dtor(session, 1, &session->local.comp_abstract);
}
/* mac */
if (session->local.mac && session->local.mac->dtor) {
session->local.mac->dtor(session, &session->local.mac_abstract);
}
/* Server to Client */
/* crypt */
if (session->remote.crypt && session->remote.crypt->dtor) {
session->remote.crypt->dtor(session, &session->remote.crypt_abstract);
}
/* comp */
if (session->remote.comp && session->remote.comp->dtor) {
session->remote.comp->dtor(session, 0, &session->remote.comp_abstract);
}
/* mac */
if (session->remote.mac && session->remote.mac->dtor) {
session->remote.mac->dtor(session, &session->remote.mac_abstract);
}
/* session_id */
if (session->session_id) {
LIBSSH2_FREE(session, session->session_id);
}
}
/* Free banner(s) */
if (session->remote.banner) {
LIBSSH2_FREE(session, session->remote.banner);
}
if (session->local.banner) {
LIBSSH2_FREE(session, session->local.banner);
}
/* Free preference(s) */
if (session->kex_prefs) {
LIBSSH2_FREE(session, session->kex_prefs);
}
if (session->hostkey_prefs) {
LIBSSH2_FREE(session, session->hostkey_prefs);
}
if (session->local.crypt_prefs) {
LIBSSH2_FREE(session, session->local.crypt_prefs);
}
if (session->local.mac_prefs) {
LIBSSH2_FREE(session, session->local.mac_prefs);
}
if (session->local.comp_prefs) {
LIBSSH2_FREE(session, session->local.comp_prefs);
}
if (session->local.lang_prefs) {
LIBSSH2_FREE(session, session->local.lang_prefs);
}
if (session->remote.crypt_prefs) {
LIBSSH2_FREE(session, session->remote.crypt_prefs);
}
if (session->remote.mac_prefs) {
LIBSSH2_FREE(session, session->remote.mac_prefs);
}
if (session->remote.comp_prefs) {
LIBSSH2_FREE(session, session->remote.comp_prefs);
}
if (session->remote.lang_prefs) {
LIBSSH2_FREE(session, session->remote.lang_prefs);
}
/* Cleanup any remaining packets */
while (session->packets.head) {
LIBSSH2_PACKET *tmp = session->packets.head;
/* unlink */
session->packets.head = tmp->next;
/* free */
LIBSSH2_FREE(session, tmp->data);
LIBSSH2_FREE(session, tmp);
}
LIBSSH2_FREE(session, session);
}
/* }}} */
/* {{{ libssh2_session_disconnect_ex
*/
LIBSSH2_API int libssh2_session_disconnect_ex(LIBSSH2_SESSION *session, int reason, const char *description, const char *lang)
{
unsigned char *s, *data;
unsigned long data_len, descr_len = 0, lang_len = 0;
#ifdef LIBSSH2_DEBUG_TRANSPORT
_libssh2_debug(session, LIBSSH2_DBG_TRANS, "Disconnecting: reason=%d, desc=%s, lang=%s", reason, description, lang);
#endif
if (description) {
descr_len = strlen(description);
}
if (lang) {
lang_len = strlen(lang);
}
data_len = descr_len + lang_len + 13; /* packet_type(1) + reason code(4) + descr_len(4) + lang_len(4) */
s = data = LIBSSH2_ALLOC(session, data_len);
if (!data) {
libssh2_error(session, LIBSSH2_ERROR_ALLOC, "Unable to allocate memory for disconnect packet", 0);
return -1;
}
*(s++) = SSH_MSG_DISCONNECT;
libssh2_htonu32(s, reason); s += 4;
libssh2_htonu32(s, descr_len); s += 4;
if (description) {
memcpy(s, description, descr_len);
s += descr_len;
}
libssh2_htonu32(s, lang_len); s += 4;
if (lang) {
memcpy(s, lang, lang_len);
s += lang_len;
}
libssh2_packet_write(session, data, data_len);
LIBSSH2_FREE(session, data);
return 0;
}
/* }}} */
/* {{{ libssh2_session_methods
* Return the currently active methods for method_type
* NOTE: Currently lang_cs and lang_sc are ALWAYS set to empty string regardless of actual negotiation
* Strings should NOT be freed
*/
LIBSSH2_API const char *libssh2_session_methods(LIBSSH2_SESSION *session, int method_type)
{
/* All methods have char *name as their first element */
LIBSSH2_KEX_METHOD *method = NULL;
switch(method_type) {
case LIBSSH2_METHOD_KEX:
method = session->kex;
break;
case LIBSSH2_METHOD_HOSTKEY:
method = (LIBSSH2_KEX_METHOD*)session->hostkey;
break;
case LIBSSH2_METHOD_CRYPT_CS:
method = (LIBSSH2_KEX_METHOD*)session->local.crypt;
break;
case LIBSSH2_METHOD_CRYPT_SC:
method = (LIBSSH2_KEX_METHOD*)session->remote.crypt;
break;
case LIBSSH2_METHOD_MAC_CS:
method = (LIBSSH2_KEX_METHOD*)session->local.mac;
break;
case LIBSSH2_METHOD_MAC_SC:
method = (LIBSSH2_KEX_METHOD*)session->remote.mac;
break;
case LIBSSH2_METHOD_COMP_CS:
method = (LIBSSH2_KEX_METHOD*)session->local.comp;
break;
case LIBSSH2_METHOD_COMP_SC:
method = (LIBSSH2_KEX_METHOD*)session->remote.comp;
break;
case LIBSSH2_METHOD_LANG_CS:
return "";
break;
case LIBSSH2_METHOD_LANG_SC:
return "";
break;
default:
libssh2_error(session, LIBSSH2_ERROR_INVAL, "Invalid parameter specified for method_type", 0);
return NULL;
break;
}
if (!method) {
libssh2_error(session, LIBSSH2_ERROR_METHOD_NONE, "No method negotiated", 0);
return NULL;
}
return method->name;
}
/* }}} */
/* {{{ libssh2_session_abstract
* Retrieve a pointer to the abstract property
*/
LIBSSH2_API void **libssh2_session_abstract(LIBSSH2_SESSION *session)
{
return &session->abstract;
}
/* }}} */
/* {{{ libssh2_session_last_error
* Returns error code and populates an error string into errmsg
* If want_buf is non-zero then the string placed into errmsg must be freed by the calling program
* Otherwise it is assumed to be owned by libssh2
*/
LIBSSH2_API int libssh2_session_last_error(LIBSSH2_SESSION *session, char **errmsg, int *errmsg_len, int want_buf)
{
/* No error to report */
if (!session->err_code) {
if (errmsg) {
if (want_buf) {
*errmsg = LIBSSH2_ALLOC(session, 1);
if (*errmsg) {
**errmsg = 0;
}
} else {
*errmsg = "";
}
}
if (errmsg_len) {
*errmsg_len = 0;
}
return 0;
}
if (errmsg) {
char *serrmsg = session->err_msg ? session->err_msg : "";
int ownbuf = session->err_msg ? session->err_should_free : 0;
if (want_buf) {
if (ownbuf) {
/* Just give the calling program the buffer */
*errmsg = serrmsg;
session->err_should_free = 0;
} else {
/* Make a copy so the calling program can own it */
*errmsg = LIBSSH2_ALLOC(session, session->err_msglen + 1);
if (*errmsg) {
memcpy(*errmsg, session->err_msg, session->err_msglen);
(*errmsg)[session->err_msglen] = 0;
}
}
} else {
*errmsg = serrmsg;
}
}
if (errmsg_len) {
*errmsg_len = session->err_msglen;
}
return session->err_code;
}
/* }}} */
/* {{{ libssh2_session_flag
* Set/Get session flags
* Passing flag==0 will avoid changing session->flags while still returning its current value
*/
LIBSSH2_API int libssh2_session_flag(LIBSSH2_SESSION *session, int flag, int value)
{
if (value) {
session->flags |= flag;
} else {
session->flags &= ~flag;
}
return session->flags;
}
/* }}} */
/* {{{ libssh2_poll_channel_read
* Returns 0 if no data is waiting on channel,
* non-0 if data is available
*/
LIBSSH2_API int libssh2_poll_channel_read(LIBSSH2_CHANNEL *channel, int extended)
{
LIBSSH2_SESSION *session = channel->session;
LIBSSH2_PACKET *packet = session->packets.head;
while (packet) {
if (((packet->data[0] == SSH_MSG_CHANNEL_DATA) && (extended == 0) && (channel->local.id == libssh2_ntohu32(packet->data + 1))) ||
((packet->data[0] == SSH_MSG_CHANNEL_EXTENDED_DATA) && (extended != 0) && (channel->local.id == libssh2_ntohu32(packet->data + 1)))) {
/* Found data waiting to be read */
return 1;
}
packet = packet->next;
}
return 0;
}
/* }}} */
/* {{{ libssh2_poll_channel_write
* Returns 0 if writing to channel would block,
* non-0 if data can be written without blocking
*/
inline int libssh2_poll_channel_write(LIBSSH2_CHANNEL *channel)
{
return channel->local.window_size ? 1 : 0;
}
/* }}} */
/* {{{ libssh2_poll_listener_queued
* Returns 0 if no connections are waiting to be accepted
* non-0 if one or more connections are available
*/
inline int libssh2_poll_listener_queued(LIBSSH2_LISTENER *listener)
{
return listener->queue ? 1 : 0;
}
/* }}} */
/* {{{ libssh2_poll
* Poll sockets, channels, and listeners for activity
*/
LIBSSH2_API int libssh2_poll(LIBSSH2_POLLFD *fds, unsigned int nfds, long timeout)
{
long timeout_remaining;
int i, active_fds;
#ifdef HAVE_POLL
LIBSSH2_SESSION *session = NULL;
struct pollfd sockets[nfds];
/* Setup sockets for polling */
for(i = 0; i < nfds; i++) {
fds[i].revents = 0;
switch (fds[i].type) {
case LIBSSH2_POLLFD_SOCKET:
sockets[i].fd = fds[i].fd.socket;
sockets[i].events = fds[i].events;
sockets[i].revents = 0;
break;
case LIBSSH2_POLLFD_CHANNEL:
sockets[i].fd = fds[i].fd.channel->session->socket_fd;
sockets[i].events = POLLIN;
sockets[i].revents = 0;
if (!session) session = fds[i].fd.channel->session;
break;
case LIBSSH2_POLLFD_LISTENER:
sockets[i].fd = fds[i].fd.listener->session->socket_fd;
sockets[i].events = POLLIN;
sockets[i].revents = 0;
if (!session) session = fds[i].fd.listener->session;
break;
default:
if (session) libssh2_error(session, LIBSSH2_ERROR_INVALID_POLL_TYPE, "Invalid descriptor passed to libssh2_poll()", 0);
return -1;
}
}
#elif defined(HAVE_SELECT)
LIBSSH2_SESSION *session = NULL;
int maxfd = 0;
fd_set rfds,wfds;
struct timeval tv;
FD_ZERO(&rfds);
FD_ZERO(&wfds);
for(i = 0; i < nfds; i++) {
fds[i].revents = 0;
switch (fds[i].type) {
case LIBSSH2_POLLFD_SOCKET:
if (fds[i].events & LIBSSH2_POLLFD_POLLIN) {
FD_SET(fds[i].fd.socket, &rfds);
if (fds[i].fd.socket > maxfd) maxfd = fds[i].fd.socket;
}
if (fds[i].events & LIBSSH2_POLLFD_POLLOUT) {
FD_SET(fds[i].fd.socket, &wfds);
if (fds[i].fd.socket > maxfd) maxfd = fds[i].fd.socket;
}
break;
case LIBSSH2_POLLFD_CHANNEL:
FD_SET(fds[i].fd.channel->session->socket_fd, &rfds);
if (fds[i].fd.channel->session->socket_fd > maxfd) maxfd = fds[i].fd.channel->session->socket_fd;
if (!session) session = fds[i].fd.channel->session;
break;
case LIBSSH2_POLLFD_LISTENER:
FD_SET(fds[i].fd.listener->session->socket_fd, &rfds);
if (fds[i].fd.listener->session->socket_fd > maxfd) maxfd = fds[i].fd.listener->session->socket_fd;
if (!session) session = fds[i].fd.listener->session;
break;
default:
if (session) libssh2_error(session, LIBSSH2_ERROR_INVALID_POLL_TYPE, "Invalid descriptor passed to libssh2_poll()", 0);
return -1;
}
}
#else
/* No select() or poll()
* no sockets sturcture to setup
*/
timeout = 0;
#endif /* HAVE_POLL or HAVE_SELECT */
timeout_remaining = timeout;
do {
#if defined(HAVE_POLL) || defined(HAVE_SELECT)
int sysret;
#endif
active_fds = 0;
for (i = 0; i < nfds; i++) {
if (fds[i].events != fds[i].revents) {
switch (fds[i].type) {
case LIBSSH2_POLLFD_CHANNEL:
if ((fds[i].events & LIBSSH2_POLLFD_POLLIN) && /* Want to be ready for read */
((fds[i].revents & LIBSSH2_POLLFD_POLLIN) == 0)) { /* Not yet known to be ready for read */
fds[i].revents |= libssh2_poll_channel_read(fds[i].fd.channel, 0) ? LIBSSH2_POLLFD_POLLIN : 0;
}
if ((fds[i].events & LIBSSH2_POLLFD_POLLEXT) && /* Want to be ready for extended read */
((fds[i].revents & LIBSSH2_POLLFD_POLLEXT) == 0)) { /* Not yet known to be ready for extended read */
fds[i].revents |= libssh2_poll_channel_read(fds[i].fd.channel, 1) ? LIBSSH2_POLLFD_POLLEXT : 0;
}
if ((fds[i].events & LIBSSH2_POLLFD_POLLOUT) && /* Want to be ready for write */
((fds[i].revents & LIBSSH2_POLLFD_POLLOUT) == 0)) { /* Not yet known to be ready for write */
fds[i].revents |= libssh2_poll_channel_write(fds[i].fd.channel) ? LIBSSH2_POLLFD_POLLOUT : 0;
}
if (fds[i].fd.channel->remote.close || fds[i].fd.channel->local.close) {
fds[i].revents |= LIBSSH2_POLLFD_CHANNEL_CLOSED;
}
if (fds[i].fd.channel->session->socket_state == LIBSSH2_SOCKET_DISCONNECTED) {
fds[i].revents |= LIBSSH2_POLLFD_CHANNEL_CLOSED | LIBSSH2_POLLFD_SESSION_CLOSED;
}
break;
case LIBSSH2_POLLFD_LISTENER:
if ((fds[i].events & LIBSSH2_POLLFD_POLLIN) && /* Want a connection */
((fds[i].revents & LIBSSH2_POLLFD_POLLIN) == 0)) { /* No connections known of yet */
fds[i].revents |= libssh2_poll_listener_queued(fds[i].fd.listener) ? LIBSSH2_POLLFD_POLLIN : 0;
}
if (fds[i].fd.listener->session->socket_state == LIBSSH2_SOCKET_DISCONNECTED) {
fds[i].revents |= LIBSSH2_POLLFD_LISTENER_CLOSED | LIBSSH2_POLLFD_SESSION_CLOSED;
}
break;
}
}
if (fds[i].revents) {
active_fds++;
}
}
if (active_fds) {
/* Don't block on the sockets if we have channels/listeners which are ready */
timeout_remaining = 0;
}
#ifdef HAVE_POLL
#ifdef HAVE_GETTIMEOFDAY
{
struct timeval tv_begin, tv_end;
gettimeofday((struct timeval *)&tv_begin, NULL);
sysret = poll(sockets, nfds, timeout_remaining);
gettimeofday((struct timeval *)&tv_end, NULL);
timeout_remaining -= (tv_end.tv_sec - tv_begin.tv_sec) * 1000;
timeout_remaining -= (tv_end.tv_usec - tv_begin.tv_usec) / 1000;
}
#else
/* If the platform doesn't support gettimeofday,
* then just make the call non-blocking and walk away
*/
sysret = poll(sockets, nfds, timeout_remaining);
timeout_remaining = 0;
#endif /* HAVE_GETTIMEOFDAY */
if (sysret > 0) {
for (i = 0; i < nfds; i++) {
switch (fds[i].type) {
case LIBSSH2_POLLFD_SOCKET:
fds[i].revents = sockets[i].revents;
sockets[i].revents = 0; /* In case we loop again, be nice */
if (fds[i].revents) {
active_fds++;
}
break;
case LIBSSH2_POLLFD_CHANNEL:
if (sockets[i].events & POLLIN) {
/* Spin session until no data available */
while (libssh2_packet_read(fds[i].fd.channel->session, 0) > 0);
}
if (sockets[i].revents & POLLHUP) {
fds[i].revents |= LIBSSH2_POLLFD_CHANNEL_CLOSED | LIBSSH2_POLLFD_SESSION_CLOSED;
}
sockets[i].revents = 0;
break;
case LIBSSH2_POLLFD_LISTENER:
if (sockets[i].events & POLLIN) {
/* Spin session until no data available */
while (libssh2_packet_read(fds[i].fd.listener->session, 0) > 0);
}
if (sockets[i].revents & POLLHUP) {
fds[i].revents |= LIBSSH2_POLLFD_LISTENER_CLOSED | LIBSSH2_POLLFD_SESSION_CLOSED;
}
sockets[i].revents = 0;
break;
}
}
}
#elif defined(HAVE_SELECT)
tv.tv_sec = timeout_remaining / 1000;
tv.tv_usec = (timeout_remaining % 1000) * 1000;
#ifdef HAVE_GETTIMEOFDAY
{
struct timeval tv_begin, tv_end;
gettimeofday((struct timeval *)&tv_begin, NULL);
sysret = select(maxfd, &rfds, &wfds, NULL, &tv);
gettimeofday((struct timeval *)&tv_end, NULL);
timeout_remaining -= (tv_end.tv_sec - tv_begin.tv_sec) * 1000;
timeout_remaining -= (tv_end.tv_usec - tv_begin.tv_usec) / 1000;
}
#else
/* If the platform doesn't support gettimeofday,
* then just make the call non-blocking and walk away
*/
sysret = select(maxfd, &rfds, &wfds, NULL, &tv);
timeout_remaining = 0;
#endif
if (sysret > 0) {
for (i = 0; i < nfds; i++) {
switch (fds[i].type) {
case LIBSSH2_POLLFD_SOCKET:
if (FD_ISSET(fds[i].fd.socket, &rfds)) {
fds[i].revents |= LIBSSH2_POLLFD_POLLIN;
}
if (FD_ISSET(fds[i].fd.socket, &wfds)) {
fds[i].revents |= LIBSSH2_POLLFD_POLLOUT;
}
if (fds[i].revents) {
active_fds++;
}
break;
case LIBSSH2_POLLFD_CHANNEL:
if (FD_ISSET(fds[i].fd.channel->session->socket_fd, &rfds)) {
/* Spin session until no data available */
while (libssh2_packet_read(fds[i].fd.channel->session, 0) > 0);