circuitpython/supervisor/shared/web_workflow/websocket.c

262 lines
8.6 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2022 Scott Shawcroft for Adafruit Industries
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "supervisor/shared/web_workflow/websocket.h"
#include "py/ringbuf.h"
#include "py/runtime.h"
#include "shared/runtime/interrupt_char.h"
#include "shared-bindings/socketpool/SocketPool.h"
#include "supervisor/shared/web_workflow/web_workflow.h"
#if CIRCUITPY_STATUS_BAR
#include "supervisor/shared/status_bar.h"
#endif
typedef struct {
socketpool_socket_obj_t socket;
uint8_t opcode;
uint8_t frame_len;
uint8_t payload_len_size;
bool masked;
uint8_t mask[4];
int frame_index;
size_t payload_remaining;
} _websocket;
// Buffer the incoming serial data in the background so that we can look for the
// interrupt character.
STATIC ringbuf_t _incoming_ringbuf;
STATIC uint8_t _buf[16];
// make sure background is not called recursively
STATIC bool in_web_background = false;
static _websocket cp_serial;
void websocket_init(void) {
socketpool_socket_reset(&cp_serial.socket);
ringbuf_init(&_incoming_ringbuf, _buf, sizeof(_buf));
}
void websocket_handoff(socketpool_socket_obj_t *socket) {
if (!common_hal_socketpool_socket_get_closed(&cp_serial.socket)) {
common_hal_socketpool_socket_close(&cp_serial.socket);
}
socketpool_socket_move(socket, &cp_serial.socket);
cp_serial.opcode = 0;
cp_serial.frame_index = 0;
cp_serial.frame_len = 2;
#if CIRCUITPY_STATUS_BAR
// Send the title bar for the new client.
supervisor_status_bar_request_update(true);
#endif
}
bool websocket_connected(void) {
return _incoming_ringbuf.size > 0 &&
!common_hal_socketpool_socket_get_closed(&cp_serial.socket) &&
common_hal_socketpool_socket_get_connected(&cp_serial.socket);
}
static bool _read_byte(uint8_t *c) {
int len = socketpool_socket_recv_into(&cp_serial.socket, c, 1);
if (len < 1) {
return false;
}
return true;
}
static void _read_next_frame_header(void) {
uint8_t h;
if (cp_serial.frame_index == 0 && _read_byte(&h)) {
cp_serial.frame_index++;
cp_serial.opcode = h & 0xf;
}
if (cp_serial.frame_index == 1 && _read_byte(&h)) {
cp_serial.frame_index++;
uint8_t len = h & 0x7f;
cp_serial.masked = (h >> 7) == 1;
if (len <= 125) {
cp_serial.payload_remaining = len;
cp_serial.payload_len_size = 0;
} else if (len == 126) { // 16 bit length
cp_serial.payload_len_size = 2;
} else if (len == 127) { // 64 bit length
cp_serial.payload_len_size = 8;
}
cp_serial.frame_len = 2 + cp_serial.payload_len_size;
if (cp_serial.masked) {
cp_serial.frame_len += 4;
}
}
while (cp_serial.frame_index >= 2 &&
cp_serial.frame_index < (cp_serial.payload_len_size + 2) &&
_read_byte(&h)) {
cp_serial.frame_index++;
cp_serial.payload_remaining = cp_serial.payload_remaining << 8 | h;
}
int mask_start = cp_serial.payload_len_size + 2;
while (cp_serial.frame_index >= mask_start &&
cp_serial.frame_index < cp_serial.frame_len &&
_read_byte(&h)) {
size_t mask_offset = cp_serial.frame_index - mask_start;
cp_serial.mask[mask_offset] = h;
cp_serial.frame_index++;
}
// Reply to PINGs and CLOSE.
while ((cp_serial.opcode == 0x8 ||
cp_serial.opcode == 0x9) &&
cp_serial.frame_index >= cp_serial.frame_len) {
if (cp_serial.frame_index == cp_serial.frame_len) {
uint8_t opcode = 0x8; // CLOSE
if (cp_serial.opcode == 0x9) {
opcode = 0xA; // PONG
} else {
// Set the TCP socket to send immediately so that we send the payload back before
// closing the connection.
int nodelay = 1;
common_hal_socketpool_socket_setsockopt(&cp_serial.socket, SOCKETPOOL_IPPROTO_TCP, SOCKETPOOL_TCP_NODELAY, &nodelay, sizeof(nodelay));
}
uint8_t frame_header[2];
frame_header[0] = 1 << 7 | opcode;
frame_header[1] = cp_serial.payload_remaining;
web_workflow_send_raw(&cp_serial.socket, (const uint8_t *)frame_header, 2);
}
if (cp_serial.payload_remaining > 0 && _read_byte(&h)) {
// Send the payload back to the client.
cp_serial.frame_index++;
cp_serial.payload_remaining--;
web_workflow_send_raw(&cp_serial.socket, &h, 1);
}
if (cp_serial.payload_remaining == 0) {
cp_serial.frame_index = 0;
if (cp_serial.opcode == 0x8) {
common_hal_socketpool_socket_close(&cp_serial.socket);
}
}
}
}
static bool _read_next_payload_byte(uint8_t *c) {
_read_next_frame_header();
if (cp_serial.opcode == 0x1 &&
cp_serial.frame_index >= cp_serial.frame_len &&
cp_serial.payload_remaining > 0) {
if (_read_byte(c)) {
uint8_t mask_offset = (cp_serial.frame_index - cp_serial.frame_len) % 4;
*c ^= cp_serial.mask[mask_offset];
cp_serial.frame_index++;
cp_serial.payload_remaining--;
if (cp_serial.payload_remaining == 0) {
cp_serial.frame_index = 0;
}
return true;
}
}
return false;
}
bool websocket_available(void) {
if (!websocket_connected()) {
return false;
}
websocket_background();
return ringbuf_num_filled(&_incoming_ringbuf) > 0;
}
char websocket_read_char(void) {
websocket_background();
if (ringbuf_num_filled(&_incoming_ringbuf) > 0) {
return ringbuf_get(&_incoming_ringbuf);
}
return -1;
}
static void _websocket_send(_websocket *ws, const char *text, size_t len) {
if (!websocket_connected()) {
return;
}
uint32_t opcode = 1;
uint8_t frame_header[2];
frame_header[0] = 1 << 7 | opcode;
uint8_t payload_len;
if (len <= 125) {
payload_len = len;
} else if (len < (1 << 16)) {
payload_len = 126;
} else {
payload_len = 127;
}
frame_header[1] = payload_len;
web_workflow_send_raw(&ws->socket, (const uint8_t *)frame_header, 2);
uint8_t extended_len[4];
if (payload_len == 126) {
extended_len[0] = (len >> 8) & 0xff;
extended_len[1] = len & 0xff;
web_workflow_send_raw(&ws->socket, extended_len, 2);
} else if (payload_len == 127) {
uint32_t zero = 0;
// 64 bits where top four bytes are zero.
web_workflow_send_raw(&ws->socket, (const uint8_t *)&zero, 4);
extended_len[0] = (len >> 24) & 0xff;
extended_len[1] = (len >> 16) & 0xff;
extended_len[2] = (len >> 8) & 0xff;
extended_len[3] = len & 0xff;
web_workflow_send_raw(&ws->socket, extended_len, 4);
}
web_workflow_send_raw(&ws->socket, (const uint8_t *)text, len);
}
void websocket_write(const char *text, size_t len) {
_websocket_send(&cp_serial, text, len);
}
void websocket_background(void) {
if (!websocket_connected()) {
return;
}
if (in_web_background) {
return;
}
in_web_background = true;
uint8_t c;
while (ringbuf_num_empty(&_incoming_ringbuf) > 0 &&
_read_next_payload_byte(&c)) {
if (c == mp_interrupt_char) {
mp_sched_keyboard_interrupt();
continue;
}
ringbuf_put(&_incoming_ringbuf, c);
}
in_web_background = false;
}