extmod/moduwebsocket.c - lite/micropython - Linaro Git Browser

 /*
  * This file is part of the MicroPython project, http://micropython.org/
  *
  * The MIT License (MIT)
  *
  * Copyright (c) 2016 Paul Sokolovsky
  *
  * 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 <stdio.h>
 #include <stdint.h>
 #include <string.h>

 #include "py/runtime.h"
 #include "py/stream.h"
 #include "extmod/moduwebsocket.h"

 #if MICROPY_PY_UWEBSOCKET

 enum { FRAME_HEADER, FRAME_OPT, PAYLOAD, CONTROL };

 enum { BLOCKING_WRITE = 0x80 };

 typedef struct _mp_obj_websocket_t {
     mp_obj_base_t base;
     mp_obj_t sock;
     uint32_t msg_sz;
     byte mask[4];
     byte state;
     byte to_recv;
     byte mask_pos;
     byte buf_pos;
     byte buf[6];
     byte opts;
     // Copy of last data frame flags
     byte ws_flags;
     // Copy of current frame flags
     byte last_flags;
 } mp_obj_websocket_t;

 STATIC mp_uint_t websocket_write(mp_obj_t self_in, const void *buf, mp_uint_t size, int *errcode);

 STATIC mp_obj_t websocket_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
     mp_arg_check_num(n_args, n_kw, 1, 2, false);
     mp_get_stream_raise(args[0], MP_STREAM_OP_READ | MP_STREAM_OP_WRITE | MP_STREAM_OP_IOCTL);
     mp_obj_websocket_t *o = m_new_obj(mp_obj_websocket_t);
     o->base.type = type;
     o->sock = args[0];
     o->state = FRAME_HEADER;
     o->to_recv = 2;
     o->mask_pos = 0;
     o->buf_pos = 0;
     o->opts = FRAME_TXT;
     if (n_args > 1 && args[1] == mp_const_true) {
         o->opts |= BLOCKING_WRITE;
     }
     return MP_OBJ_FROM_PTR(o);
 }

 STATIC mp_uint_t websocket_read(mp_obj_t self_in, void *buf, mp_uint_t size, int *errcode) {
     mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
     const mp_stream_p_t *stream_p = mp_get_stream(self->sock);
     while (1) {
         if (self->to_recv != 0) {
             mp_uint_t out_sz = stream_p->read(self->sock, self->buf + self->buf_pos, self->to_recv, errcode);
             if (out_sz == 0 || out_sz == MP_STREAM_ERROR) {
                 return out_sz;
             }
             self->buf_pos += out_sz;
             self->to_recv -= out_sz;
             if (self->to_recv != 0) {
                 *errcode = MP_EAGAIN;
                 return MP_STREAM_ERROR;
             }
         }

         switch (self->state) {
             case FRAME_HEADER: {
                 // TODO: Split frame handling below is untested so far, so conservatively disable it
                 assert(self->buf[0] & 0x80);

                 // "Control frames MAY be injected in the middle of a fragmented message."
                 // So, they must be processed before data frames (and not alter
                 // self->ws_flags)
                 byte frame_type = self->buf[0];
                 self->last_flags = frame_type;
                 frame_type &= FRAME_OPCODE_MASK;

                 if ((self->buf[0] & FRAME_OPCODE_MASK) == FRAME_CONT) {
                     // Preserve previous frame type
                     self->ws_flags = (self->ws_flags & FRAME_OPCODE_MASK) | (self->buf[0] & ~FRAME_OPCODE_MASK);
                 } else {
                     self->ws_flags = self->buf[0];
                 }

                 // Reset mask in case someone will use "simplified" protocol
                 // without masks.
                 memset(self->mask, 0, sizeof(self->mask));

                 int to_recv = 0;
                 size_t sz = self->buf[1] & 0x7f;
                 if (sz == 126) {
                     // Msg size is next 2 bytes
                     to_recv += 2;
                 } else if (sz == 127) {
                     // Msg size is next 8 bytes
                     assert(0);
                 }
                 if (self->buf[1] & 0x80) {
                     // Next 4 bytes is mask
                     to_recv += 4;
                 }

                 self->buf_pos = 0;
                 self->to_recv = to_recv;
                 self->msg_sz = sz; // May be overridden by FRAME_OPT
                 if (to_recv != 0) {
                     self->state = FRAME_OPT;
                 } else {
                     if (frame_type >= FRAME_CLOSE) {
                         self->state = CONTROL;
                     } else {
                         self->state = PAYLOAD;
                     }
                 }
                 continue;
             }

             case FRAME_OPT: {
                 if ((self->buf_pos & 3) == 2) {
                     // First two bytes are message length
                     self->msg_sz = (self->buf[0] << 8) | self->buf[1];
                 }
                 if (self->buf_pos >= 4) {
                     // Last 4 bytes is mask
                     memcpy(self->mask, self->buf + self->buf_pos - 4, 4);
                 }
                 self->buf_pos = 0;
                 if ((self->last_flags & FRAME_OPCODE_MASK) >= FRAME_CLOSE) {
                     self->state = CONTROL;
                 } else {
                     self->state = PAYLOAD;
                 }
                 continue;
             }

             case PAYLOAD:
             case CONTROL: {
                 mp_uint_t out_sz = 0;
                 if (self->msg_sz == 0) {
                     // In case message had zero payload
                     goto no_payload;
                 }

                 size_t sz = MIN(size, self->msg_sz);
                 out_sz = stream_p->read(self->sock, buf, sz, errcode);
                 if (out_sz == 0 || out_sz == MP_STREAM_ERROR) {
                     return out_sz;
                 }

                 sz = out_sz;
                 for (byte *p = buf; sz--; p++) {
                     *p ^= self->mask[self->mask_pos++ & 3];
                 }

                 self->msg_sz -= out_sz;
                 if (self->msg_sz == 0) {
                     byte last_state;
                 no_payload:
                     last_state = self->state;
                     self->state = FRAME_HEADER;
                     self->to_recv = 2;
                     self->mask_pos = 0;
                     self->buf_pos = 0;

                     // Handle control frame
                     if (last_state == CONTROL) {
                         byte frame_type = self->last_flags & FRAME_OPCODE_MASK;
                         if (frame_type == FRAME_CLOSE) {
                             static const char close_resp[2] = {0x88, 0};
                             int err;
                             websocket_write(self_in, close_resp, sizeof(close_resp), &err);
                             return 0;
                         }

                         //DEBUG_printf("Finished receiving ctrl message %x, ignoring\n", self->last_flags);
                         continue;
                     }
                 }

                 if (out_sz != 0) {
                     return out_sz;
                 }
                 // Empty (data) frame received is not EOF
                 continue;
             }

         }
     }
 }

 STATIC mp_uint_t websocket_write(mp_obj_t self_in, const void *buf, mp_uint_t size, int *errcode) {
     mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
     assert(size < 0x10000);
     byte header[4] = {0x80 | (self->opts & FRAME_OPCODE_MASK)};
     int hdr_sz;
     if (size < 126) {
         header[1] = size;
         hdr_sz = 2;
     } else {
         header[1] = 126;
         header[2] = size >> 8;
         header[3] = size & 0xff;
         hdr_sz = 4;
     }

     mp_obj_t dest[3];
     if (self->opts & BLOCKING_WRITE) {
         mp_load_method(self->sock, MP_QSTR_setblocking, dest);
         dest[2] = mp_const_true;
         mp_call_method_n_kw(1, 0, dest);
     }

     mp_uint_t out_sz = mp_stream_write_exactly(self->sock, header, hdr_sz, errcode);
     if (*errcode == 0) {
         out_sz = mp_stream_write_exactly(self->sock, buf, size, errcode);
     }

     if (self->opts & BLOCKING_WRITE) {
         dest[2] = mp_const_false;
         mp_call_method_n_kw(1, 0, dest);
     }

     if (*errcode != 0) {
         return MP_STREAM_ERROR;
     }
     return out_sz;
 }

 STATIC mp_uint_t websocket_ioctl(mp_obj_t self_in, mp_uint_t request, uintptr_t arg, int *errcode) {
     mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
     switch (request) {
         case MP_STREAM_CLOSE:
             // TODO: Send close signaling to the other side, otherwise it's
             // abrupt close (connection abort).
             mp_stream_close(self->sock);
             return 0;
         case MP_STREAM_GET_DATA_OPTS:
             return self->ws_flags & FRAME_OPCODE_MASK;
         case MP_STREAM_SET_DATA_OPTS: {
             int cur = self->opts & FRAME_OPCODE_MASK;
             self->opts = (self->opts & ~FRAME_OPCODE_MASK) | (arg & FRAME_OPCODE_MASK);
             return cur;
         }
         default:
             *errcode = MP_EINVAL;
             return MP_STREAM_ERROR;
     }
 }

 STATIC const mp_rom_map_elem_t websocket_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
     { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
     { MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
     { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
     { MP_ROM_QSTR(MP_QSTR_ioctl), MP_ROM_PTR(&mp_stream_ioctl_obj) },
     { MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&mp_stream_close_obj) },
 };
 STATIC MP_DEFINE_CONST_DICT(websocket_locals_dict, websocket_locals_dict_table);

 STATIC const mp_stream_p_t websocket_stream_p = {
     .read = websocket_read,
     .write = websocket_write,
     .ioctl = websocket_ioctl,
 };

 STATIC const mp_obj_type_t websocket_type = {
     { &mp_type_type },
     .name = MP_QSTR_websocket,
     .make_new = websocket_make_new,
     .protocol = &websocket_stream_p,
     .locals_dict = (void *)&websocket_locals_dict,
 };

 STATIC const mp_rom_map_elem_t uwebsocket_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_uwebsocket) },
     { MP_ROM_QSTR(MP_QSTR_websocket), MP_ROM_PTR(&websocket_type) },
 };

 STATIC MP_DEFINE_CONST_DICT(uwebsocket_module_globals, uwebsocket_module_globals_table);

 const mp_obj_module_t mp_module_uwebsocket = {
     .base = { &mp_type_module },
     .globals = (mp_obj_dict_t *)&uwebsocket_module_globals,
 };

 #endif // MICROPY_PY_UWEBSOCKET
	/*
	* This file is part of the MicroPython project, http://micropython.org/
	*
	* The MIT License (MIT)
	*
	* Copyright (c) 2016 Paul Sokolovsky
	*
	* 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 <stdio.h>
	#include <stdint.h>
	#include <string.h>

	#include "py/runtime.h"
	#include "py/stream.h"
	#include "extmod/moduwebsocket.h"

	#if MICROPY_PY_UWEBSOCKET

	enum { FRAME_HEADER, FRAME_OPT, PAYLOAD, CONTROL };

	enum { BLOCKING_WRITE = 0x80 };

	typedef struct _mp_obj_websocket_t {
	mp_obj_base_t base;
	mp_obj_t sock;
	uint32_t msg_sz;
	byte mask[4];
	byte state;
	byte to_recv;
	byte mask_pos;
	byte buf_pos;
	byte buf[6];
	byte opts;
	// Copy of last data frame flags
	byte ws_flags;
	// Copy of current frame flags
	byte last_flags;
	} mp_obj_websocket_t;

	STATIC mp_uint_t websocket_write(mp_obj_t self_in, const void buf, mp_uint_t size, int errcode);

	STATIC mp_obj_t websocket_make_new(const mp_obj_type_t type, size_t n_args, size_t n_kw, const mp_obj_t args) {
	mp_arg_check_num(n_args, n_kw, 1, 2, false);
	mp_get_stream_raise(args[0], MP_STREAM_OP_READ \| MP_STREAM_OP_WRITE \| MP_STREAM_OP_IOCTL);
	mp_obj_websocket_t *o = m_new_obj(mp_obj_websocket_t);
	o->base.type = type;
	o->sock = args[0];
	o->state = FRAME_HEADER;
	o->to_recv = 2;
	o->mask_pos = 0;
	o->buf_pos = 0;
	o->opts = FRAME_TXT;
	if (n_args > 1 && args[1] == mp_const_true) {
	o->opts \|= BLOCKING_WRITE;
	}
	return MP_OBJ_FROM_PTR(o);
	}

	STATIC mp_uint_t websocket_read(mp_obj_t self_in, void buf, mp_uint_t size, int errcode) {
	mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
	const mp_stream_p_t *stream_p = mp_get_stream(self->sock);
	while (1) {
	if (self->to_recv != 0) {
	mp_uint_t out_sz = stream_p->read(self->sock, self->buf + self->buf_pos, self->to_recv, errcode);
	if (out_sz == 0 \|\| out_sz == MP_STREAM_ERROR) {
	return out_sz;
	}
	self->buf_pos += out_sz;
	self->to_recv -= out_sz;
	if (self->to_recv != 0) {
	*errcode = MP_EAGAIN;
	return MP_STREAM_ERROR;
	}
	}

	switch (self->state) {
	case FRAME_HEADER: {
	// TODO: Split frame handling below is untested so far, so conservatively disable it
	assert(self->buf[0] & 0x80);

	// "Control frames MAY be injected in the middle of a fragmented message."
	// So, they must be processed before data frames (and not alter
	// self->ws_flags)
	byte frame_type = self->buf[0];
	self->last_flags = frame_type;
	frame_type &= FRAME_OPCODE_MASK;

	if ((self->buf[0] & FRAME_OPCODE_MASK) == FRAME_CONT) {
	// Preserve previous frame type
	self->ws_flags = (self->ws_flags & FRAME_OPCODE_MASK) \| (self->buf[0] & ~FRAME_OPCODE_MASK);
	} else {
	self->ws_flags = self->buf[0];
	}

	// Reset mask in case someone will use "simplified" protocol
	// without masks.
	memset(self->mask, 0, sizeof(self->mask));

	int to_recv = 0;
	size_t sz = self->buf[1] & 0x7f;
	if (sz == 126) {
	// Msg size is next 2 bytes
	to_recv += 2;
	} else if (sz == 127) {
	// Msg size is next 8 bytes
	assert(0);
	}
	if (self->buf[1] & 0x80) {
	// Next 4 bytes is mask
	to_recv += 4;
	}

	self->buf_pos = 0;
	self->to_recv = to_recv;
	self->msg_sz = sz; // May be overridden by FRAME_OPT
	if (to_recv != 0) {
	self->state = FRAME_OPT;
	} else {
	if (frame_type >= FRAME_CLOSE) {
	self->state = CONTROL;
	} else {
	self->state = PAYLOAD;
	}
	}
	continue;
	}

	case FRAME_OPT: {
	if ((self->buf_pos & 3) == 2) {
	// First two bytes are message length
	self->msg_sz = (self->buf[0] << 8) \| self->buf[1];
	}
	if (self->buf_pos >= 4) {
	// Last 4 bytes is mask
	memcpy(self->mask, self->buf + self->buf_pos - 4, 4);
	}
	self->buf_pos = 0;
	if ((self->last_flags & FRAME_OPCODE_MASK) >= FRAME_CLOSE) {
	self->state = CONTROL;
	} else {
	self->state = PAYLOAD;
	}
	continue;
	}

	case PAYLOAD:
	case CONTROL: {
	mp_uint_t out_sz = 0;
	if (self->msg_sz == 0) {
	// In case message had zero payload
	goto no_payload;
	}

	size_t sz = MIN(size, self->msg_sz);
	out_sz = stream_p->read(self->sock, buf, sz, errcode);
	if (out_sz == 0 \|\| out_sz == MP_STREAM_ERROR) {
	return out_sz;
	}

	sz = out_sz;
	for (byte *p = buf; sz--; p++) {
	*p ^= self->mask[self->mask_pos++ & 3];
	}

	self->msg_sz -= out_sz;
	if (self->msg_sz == 0) {
	byte last_state;
	no_payload:
	last_state = self->state;
	self->state = FRAME_HEADER;
	self->to_recv = 2;
	self->mask_pos = 0;
	self->buf_pos = 0;

	// Handle control frame
	if (last_state == CONTROL) {
	byte frame_type = self->last_flags & FRAME_OPCODE_MASK;
	if (frame_type == FRAME_CLOSE) {
	static const char close_resp[2] = {0x88, 0};
	int err;
	websocket_write(self_in, close_resp, sizeof(close_resp), &err);
	return 0;
	}

	//DEBUG_printf("Finished receiving ctrl message %x, ignoring\n", self->last_flags);
	continue;
	}
	}

	if (out_sz != 0) {
	return out_sz;
	}
	// Empty (data) frame received is not EOF
	continue;
	}

	}
	}
	}

	STATIC mp_uint_t websocket_write(mp_obj_t self_in, const void buf, mp_uint_t size, int errcode) {
	mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
	assert(size < 0x10000);
	byte header[4] = {0x80 \| (self->opts & FRAME_OPCODE_MASK)};
	int hdr_sz;
	if (size < 126) {
	header[1] = size;
	hdr_sz = 2;
	} else {
	header[1] = 126;
	header[2] = size >> 8;
	header[3] = size & 0xff;
	hdr_sz = 4;
	}

	mp_obj_t dest[3];
	if (self->opts & BLOCKING_WRITE) {
	mp_load_method(self->sock, MP_QSTR_setblocking, dest);
	dest[2] = mp_const_true;
	mp_call_method_n_kw(1, 0, dest);
	}

	mp_uint_t out_sz = mp_stream_write_exactly(self->sock, header, hdr_sz, errcode);
	if (*errcode == 0) {
	out_sz = mp_stream_write_exactly(self->sock, buf, size, errcode);
	}

	if (self->opts & BLOCKING_WRITE) {
	dest[2] = mp_const_false;
	mp_call_method_n_kw(1, 0, dest);
	}

	if (*errcode != 0) {
	return MP_STREAM_ERROR;
	}
	return out_sz;
	}

	STATIC mp_uint_t websocket_ioctl(mp_obj_t self_in, mp_uint_t request, uintptr_t arg, int *errcode) {
	mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
	switch (request) {
	case MP_STREAM_CLOSE:
	// TODO: Send close signaling to the other side, otherwise it's
	// abrupt close (connection abort).
	mp_stream_close(self->sock);
	return 0;
	case MP_STREAM_GET_DATA_OPTS:
	return self->ws_flags & FRAME_OPCODE_MASK;
	case MP_STREAM_SET_DATA_OPTS: {
	int cur = self->opts & FRAME_OPCODE_MASK;
	self->opts = (self->opts & ~FRAME_OPCODE_MASK) \| (arg & FRAME_OPCODE_MASK);
	return cur;
	}
	default:
	*errcode = MP_EINVAL;
	return MP_STREAM_ERROR;
	}
	}

	STATIC const mp_rom_map_elem_t websocket_locals_dict_table[] = {
	{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
	{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
	{ MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
	{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
	{ MP_ROM_QSTR(MP_QSTR_ioctl), MP_ROM_PTR(&mp_stream_ioctl_obj) },
	{ MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&mp_stream_close_obj) },
	};
	STATIC MP_DEFINE_CONST_DICT(websocket_locals_dict, websocket_locals_dict_table);

	STATIC const mp_stream_p_t websocket_stream_p = {
	.read = websocket_read,
	.write = websocket_write,
	.ioctl = websocket_ioctl,
	};

	STATIC const mp_obj_type_t websocket_type = {
	{ &mp_type_type },
	.name = MP_QSTR_websocket,
	.make_new = websocket_make_new,
	.protocol = &websocket_stream_p,
	.locals_dict = (void *)&websocket_locals_dict,
	};

	STATIC const mp_rom_map_elem_t uwebsocket_module_globals_table[] = {
	{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_uwebsocket) },
	{ MP_ROM_QSTR(MP_QSTR_websocket), MP_ROM_PTR(&websocket_type) },
	};

	STATIC MP_DEFINE_CONST_DICT(uwebsocket_module_globals, uwebsocket_module_globals_table);

	const mp_obj_module_t mp_module_uwebsocket = {
	.base = { &mp_type_module },
	.globals = (mp_obj_dict_t *)&uwebsocket_module_globals,
	};

	#endif // MICROPY_PY_UWEBSOCKET