guacamole-spice-protocol/src/libguac/socket.c

366 lines
9.1 KiB
C

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
#include "config.h"
#include "guacamole/error.h"
#include "guacamole/protocol.h"
#include "guacamole/socket.h"
#include "guacamole/timestamp.h"
#include <inttypes.h>
#include <pthread.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
char __guac_socket_BASE64_CHARACTERS[64] = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's',
't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', '+', '/'
};
static void* __guac_socket_keep_alive_thread(void* data) {
/* Calculate sleep interval */
struct timespec interval;
interval.tv_sec = GUAC_SOCKET_KEEP_ALIVE_INTERVAL / 1000;
interval.tv_nsec = (GUAC_SOCKET_KEEP_ALIVE_INTERVAL % 1000) * 1000000L;
/* Socket keep-alive loop */
guac_socket* socket = (guac_socket*) data;
while (socket->state == GUAC_SOCKET_OPEN) {
/* Send NOP keep-alive if it's been a while since the last output */
guac_timestamp timestamp = guac_timestamp_current();
if (timestamp - socket->last_write_timestamp >
GUAC_SOCKET_KEEP_ALIVE_INTERVAL) {
/* Send NOP */
if (guac_protocol_send_nop(socket)
|| guac_socket_flush(socket))
break;
}
/* Sleep until next keep-alive check */
nanosleep(&interval, NULL);
}
return NULL;
}
static ssize_t __guac_socket_write(guac_socket* socket,
const void* buf, size_t count) {
/* Update timestamp of last write */
socket->last_write_timestamp = guac_timestamp_current();
/* If handler defined, call it. */
if (socket->write_handler)
return socket->write_handler(socket, buf, count);
/* Otherwise, pretend everything was written. */
return count;
}
ssize_t guac_socket_write(guac_socket* socket,
const void* buf, size_t count) {
const char* buffer = buf;
/* Write until completely written */
while (count > 0) {
/* Attempt to write, return on error */
int written = __guac_socket_write(socket, buffer, count);
if (written == -1)
return 1;
/* Advance buffer as data written */
buffer += written;
count -= written;
}
return 0;
}
ssize_t guac_socket_read(guac_socket* socket, void* buf, size_t count) {
/* If handler defined, call it. */
if (socket->read_handler)
return socket->read_handler(socket, buf, count);
/* Otherwise, pretend nothing was read. */
return 0;
}
int guac_socket_select(guac_socket* socket, int usec_timeout) {
/* Call select handler if defined */
if (socket->select_handler)
return socket->select_handler(socket, usec_timeout);
/* Otherwise, assume ready. */
return 1;
}
guac_socket* guac_socket_alloc() {
guac_socket* socket = malloc(sizeof(guac_socket));
/* If no memory available, return with error */
if (socket == NULL) {
guac_error = GUAC_STATUS_NO_MEMORY;
guac_error_message = "Could not allocate memory for socket";
return NULL;
}
socket->__ready = 0;
socket->data = NULL;
socket->state = GUAC_SOCKET_OPEN;
socket->last_write_timestamp = guac_timestamp_current();
/* No keep alive ping by default */
socket->__keep_alive_enabled = 0;
/* No handlers yet */
socket->read_handler = NULL;
socket->write_handler = NULL;
socket->select_handler = NULL;
socket->free_handler = NULL;
socket->flush_handler = NULL;
socket->lock_handler = NULL;
socket->unlock_handler = NULL;
return socket;
}
void guac_socket_require_keep_alive(guac_socket* socket) {
/* Start keep-alive thread */
socket->__keep_alive_enabled = 1;
pthread_create(&(socket->__keep_alive_thread), NULL,
__guac_socket_keep_alive_thread, (void*) socket);
}
void guac_socket_instruction_begin(guac_socket* socket) {
/* Call instruction begin handler if defined */
if (socket->lock_handler)
socket->lock_handler(socket);
}
void guac_socket_instruction_end(guac_socket* socket) {
/* Call instruction end handler if defined */
if (socket->unlock_handler)
socket->unlock_handler(socket);
}
void guac_socket_free(guac_socket* socket) {
guac_socket_flush(socket);
/* Call free handler if defined */
if (socket->free_handler)
socket->free_handler(socket);
/* Mark as closed */
socket->state = GUAC_SOCKET_CLOSED;
/* Wait for keep-alive, if enabled */
if (socket->__keep_alive_enabled)
pthread_join(socket->__keep_alive_thread, NULL);
free(socket);
}
ssize_t guac_socket_write_int(guac_socket* socket, int64_t i) {
char buffer[128];
int length;
/* Write provided integer as a string */
length = snprintf(buffer, sizeof(buffer), "%"PRIi64, i);
return guac_socket_write(socket, buffer, length);
}
ssize_t guac_socket_write_string(guac_socket* socket, const char* str) {
/* Write contents of string */
if (guac_socket_write(socket, str, strlen(str)))
return 1;
return 0;
}
ssize_t __guac_socket_write_base64_triplet(guac_socket* socket,
int a, int b, int c) {
char output[4];
/* Byte 0:[AAAAAA] AABBBB BBBBCC CCCCCC */
output[0] = __guac_socket_BASE64_CHARACTERS[(a & 0xFC) >> 2];
if (b >= 0) {
/* Byte 1: AAAAAA [AABBBB] BBBBCC CCCCCC */
output[1] = __guac_socket_BASE64_CHARACTERS[((a & 0x03) << 4) | ((b & 0xF0) >> 4)];
/*
* Bytes 2 and 3, zero characters of padding:
*
* AAAAAA AABBBB [BBBBCC] CCCCCC
* AAAAAA AABBBB BBBBCC [CCCCCC]
*/
if (c >= 0) {
output[2] = __guac_socket_BASE64_CHARACTERS[((b & 0x0F) << 2) | ((c & 0xC0) >> 6)];
output[3] = __guac_socket_BASE64_CHARACTERS[c & 0x3F];
}
/*
* Bytes 2 and 3, one character of padding:
*
* AAAAAA AABBBB [BBBB--] ------
* AAAAAA AABBBB BBBB-- [------]
*/
else {
output[2] = __guac_socket_BASE64_CHARACTERS[((b & 0x0F) << 2)];
output[3] = '=';
}
}
/*
* Bytes 1, 2, and 3, two characters of padding:
*
* AAAAAA [AA----] ------ ------
* AAAAAA AA---- [------] ------
* AAAAAA AA---- ------ [------]
*/
else {
output[1] = __guac_socket_BASE64_CHARACTERS[((a & 0x03) << 4)];
output[2] = '=';
output[3] = '=';
}
/* At this point, 4 base64 bytes have been written */
if (guac_socket_write(socket, output, 4))
return -1;
/* If no second byte was provided, only one byte was written */
if (b < 0)
return 1;
/* If no third byte was provided, only two bytes were written */
if (c < 0)
return 2;
/* Otherwise, three bytes were written */
return 3;
}
ssize_t __guac_socket_write_base64_byte(guac_socket* socket, int buf) {
int* __ready_buf = socket->__ready_buf;
int retval;
__ready_buf[socket->__ready++] = buf;
/* Flush triplet */
if (socket->__ready == 3) {
retval = __guac_socket_write_base64_triplet(socket, __ready_buf[0], __ready_buf[1], __ready_buf[2]);
if (retval < 0)
return retval;
socket->__ready = 0;
}
return 1;
}
ssize_t guac_socket_write_base64(guac_socket* socket, const void* buf, size_t count) {
int retval;
const unsigned char* char_buf = (const unsigned char*) buf;
const unsigned char* end = char_buf + count;
while (char_buf < end) {
retval = __guac_socket_write_base64_byte(socket, *(char_buf++));
if (retval < 0)
return retval;
}
return 0;
}
ssize_t guac_socket_flush(guac_socket* socket) {
/* If handler defined, call it. */
if (socket->flush_handler)
return socket->flush_handler(socket);
/* Otherwise, do nothing */
return 0;
}
ssize_t guac_socket_flush_base64(guac_socket* socket) {
int retval;
/* Flush triplet to output buffer */
while (socket->__ready > 0) {
retval = __guac_socket_write_base64_byte(socket, -1);
if (retval < 0)
return retval;
}
return 0;
}