1 /*
2 * This file is part of the MicroPython project, http://micropython.org/
3 *
4 * The MIT License (MIT)
5 *
6 * Copyright (c) 2016 Paul Sokolovsky
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26
27 #include <stdio.h>
28 #include <stdint.h>
29 #include <string.h>
30
31 #include "py/runtime.h"
32 #include "py/stream.h"
33 #include "extmod/moduwebsocket.h"
34
35 #if MICROPY_PY_UWEBSOCKET
36
37 enum { FRAME_HEADER, FRAME_OPT, PAYLOAD, CONTROL };
38
39 enum { BLOCKING_WRITE = 0x80 };
40
41 typedef struct _mp_obj_websocket_t {
42 mp_obj_base_t base;
43 mp_obj_t sock;
44 uint32_t msg_sz;
45 byte mask[4];
46 byte state;
47 byte to_recv;
48 byte mask_pos;
49 byte buf_pos;
50 byte buf[6];
51 byte opts;
52 // Copy of last data frame flags
53 byte ws_flags;
54 // Copy of current frame flags
55 byte last_flags;
56 } mp_obj_websocket_t;
57
58 STATIC mp_uint_t websocket_write(mp_obj_t self_in, const void *buf, mp_uint_t size, int *errcode);
59
websocket_make_new(const mp_obj_type_t * type,size_t n_args,size_t n_kw,const mp_obj_t * args)60 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) {
61 mp_arg_check_num(n_args, n_kw, 1, 2, false);
62 mp_get_stream_raise(args[0], MP_STREAM_OP_READ | MP_STREAM_OP_WRITE | MP_STREAM_OP_IOCTL);
63 mp_obj_websocket_t *o = m_new_obj(mp_obj_websocket_t);
64 o->base.type = type;
65 o->sock = args[0];
66 o->state = FRAME_HEADER;
67 o->to_recv = 2;
68 o->mask_pos = 0;
69 o->buf_pos = 0;
70 o->opts = FRAME_TXT;
71 if (n_args > 1 && args[1] == mp_const_true) {
72 o->opts |= BLOCKING_WRITE;
73 }
74 return MP_OBJ_FROM_PTR(o);
75 }
76
websocket_read(mp_obj_t self_in,void * buf,mp_uint_t size,int * errcode)77 STATIC mp_uint_t websocket_read(mp_obj_t self_in, void *buf, mp_uint_t size, int *errcode) {
78 mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
79 const mp_stream_p_t *stream_p = mp_get_stream(self->sock);
80 while (1) {
81 if (self->to_recv != 0) {
82 mp_uint_t out_sz = stream_p->read(self->sock, self->buf + self->buf_pos, self->to_recv, errcode);
83 if (out_sz == 0 || out_sz == MP_STREAM_ERROR) {
84 return out_sz;
85 }
86 self->buf_pos += out_sz;
87 self->to_recv -= out_sz;
88 if (self->to_recv != 0) {
89 *errcode = MP_EAGAIN;
90 return MP_STREAM_ERROR;
91 }
92 }
93
94 switch (self->state) {
95 case FRAME_HEADER: {
96 // TODO: Split frame handling below is untested so far, so conservatively disable it
97 assert(self->buf[0] & 0x80);
98
99 // "Control frames MAY be injected in the middle of a fragmented message."
100 // So, they must be processed before data frames (and not alter
101 // self->ws_flags)
102 byte frame_type = self->buf[0];
103 self->last_flags = frame_type;
104 frame_type &= FRAME_OPCODE_MASK;
105
106 if ((self->buf[0] & FRAME_OPCODE_MASK) == FRAME_CONT) {
107 // Preserve previous frame type
108 self->ws_flags = (self->ws_flags & FRAME_OPCODE_MASK) | (self->buf[0] & ~FRAME_OPCODE_MASK);
109 } else {
110 self->ws_flags = self->buf[0];
111 }
112
113 // Reset mask in case someone will use "simplified" protocol
114 // without masks.
115 memset(self->mask, 0, sizeof(self->mask));
116
117 int to_recv = 0;
118 size_t sz = self->buf[1] & 0x7f;
119 if (sz == 126) {
120 // Msg size is next 2 bytes
121 to_recv += 2;
122 } else if (sz == 127) {
123 // Msg size is next 8 bytes
124 assert(0);
125 }
126 if (self->buf[1] & 0x80) {
127 // Next 4 bytes is mask
128 to_recv += 4;
129 }
130
131 self->buf_pos = 0;
132 self->to_recv = to_recv;
133 self->msg_sz = sz; // May be overridden by FRAME_OPT
134 if (to_recv != 0) {
135 self->state = FRAME_OPT;
136 } else {
137 if (frame_type >= FRAME_CLOSE) {
138 self->state = CONTROL;
139 } else {
140 self->state = PAYLOAD;
141 }
142 }
143 continue;
144 }
145
146 case FRAME_OPT: {
147 if ((self->buf_pos & 3) == 2) {
148 // First two bytes are message length
149 self->msg_sz = (self->buf[0] << 8) | self->buf[1];
150 }
151 if (self->buf_pos >= 4) {
152 // Last 4 bytes is mask
153 memcpy(self->mask, self->buf + self->buf_pos - 4, 4);
154 }
155 self->buf_pos = 0;
156 if ((self->last_flags & FRAME_OPCODE_MASK) >= FRAME_CLOSE) {
157 self->state = CONTROL;
158 } else {
159 self->state = PAYLOAD;
160 }
161 continue;
162 }
163
164 case PAYLOAD:
165 case CONTROL: {
166 mp_uint_t out_sz = 0;
167 if (self->msg_sz == 0) {
168 // In case message had zero payload
169 goto no_payload;
170 }
171
172 size_t sz = MIN(size, self->msg_sz);
173 out_sz = stream_p->read(self->sock, buf, sz, errcode);
174 if (out_sz == 0 || out_sz == MP_STREAM_ERROR) {
175 return out_sz;
176 }
177
178 sz = out_sz;
179 for (byte *p = buf; sz--; p++) {
180 *p ^= self->mask[self->mask_pos++ & 3];
181 }
182
183 self->msg_sz -= out_sz;
184 if (self->msg_sz == 0) {
185 byte last_state;
186 no_payload:
187 last_state = self->state;
188 self->state = FRAME_HEADER;
189 self->to_recv = 2;
190 self->mask_pos = 0;
191 self->buf_pos = 0;
192
193 // Handle control frame
194 if (last_state == CONTROL) {
195 byte frame_type = self->last_flags & FRAME_OPCODE_MASK;
196 if (frame_type == FRAME_CLOSE) {
197 static const char close_resp[2] = {0x88, 0};
198 int err;
199 websocket_write(self_in, close_resp, sizeof(close_resp), &err);
200 return 0;
201 }
202
203 // DEBUG_printf("Finished receiving ctrl message %x, ignoring\n", self->last_flags);
204 continue;
205 }
206 }
207
208 if (out_sz != 0) {
209 return out_sz;
210 }
211 // Empty (data) frame received is not EOF
212 continue;
213 }
214
215 }
216 }
217 }
218
websocket_write(mp_obj_t self_in,const void * buf,mp_uint_t size,int * errcode)219 STATIC mp_uint_t websocket_write(mp_obj_t self_in, const void *buf, mp_uint_t size, int *errcode) {
220 mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
221 assert(size < 0x10000);
222 byte header[4] = {0x80 | (self->opts & FRAME_OPCODE_MASK)};
223 int hdr_sz;
224 if (size < 126) {
225 header[1] = size;
226 hdr_sz = 2;
227 } else {
228 header[1] = 126;
229 header[2] = size >> 8;
230 header[3] = size & 0xff;
231 hdr_sz = 4;
232 }
233
234 mp_obj_t dest[3];
235 if (self->opts & BLOCKING_WRITE) {
236 mp_load_method(self->sock, MP_QSTR_setblocking, dest);
237 dest[2] = mp_const_true;
238 mp_call_method_n_kw(1, 0, dest);
239 }
240
241 mp_uint_t out_sz = mp_stream_write_exactly(self->sock, header, hdr_sz, errcode);
242 if (*errcode == 0) {
243 out_sz = mp_stream_write_exactly(self->sock, buf, size, errcode);
244 }
245
246 if (self->opts & BLOCKING_WRITE) {
247 dest[2] = mp_const_false;
248 mp_call_method_n_kw(1, 0, dest);
249 }
250
251 if (*errcode != 0) {
252 return MP_STREAM_ERROR;
253 }
254 return out_sz;
255 }
256
websocket_ioctl(mp_obj_t self_in,mp_uint_t request,uintptr_t arg,int * errcode)257 STATIC mp_uint_t websocket_ioctl(mp_obj_t self_in, mp_uint_t request, uintptr_t arg, int *errcode) {
258 mp_obj_websocket_t *self = MP_OBJ_TO_PTR(self_in);
259 switch (request) {
260 case MP_STREAM_CLOSE:
261 // TODO: Send close signaling to the other side, otherwise it's
262 // abrupt close (connection abort).
263 mp_stream_close(self->sock);
264 return 0;
265 case MP_STREAM_GET_DATA_OPTS:
266 return self->ws_flags & FRAME_OPCODE_MASK;
267 case MP_STREAM_SET_DATA_OPTS: {
268 int cur = self->opts & FRAME_OPCODE_MASK;
269 self->opts = (self->opts & ~FRAME_OPCODE_MASK) | (arg & FRAME_OPCODE_MASK);
270 return cur;
271 }
272 default:
273 *errcode = MP_EINVAL;
274 return MP_STREAM_ERROR;
275 }
276 }
277
278 STATIC const mp_rom_map_elem_t websocket_locals_dict_table[] = {
279 { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
280 { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
281 { MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
282 { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
283 { MP_ROM_QSTR(MP_QSTR_ioctl), MP_ROM_PTR(&mp_stream_ioctl_obj) },
284 { MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&mp_stream_close_obj) },
285 };
286 STATIC MP_DEFINE_CONST_DICT(websocket_locals_dict, websocket_locals_dict_table);
287
288 STATIC const mp_stream_p_t websocket_stream_p = {
289 .read = websocket_read,
290 .write = websocket_write,
291 .ioctl = websocket_ioctl,
292 };
293
294 STATIC const mp_obj_type_t websocket_type = {
295 { &mp_type_type },
296 .name = MP_QSTR_websocket,
297 .make_new = websocket_make_new,
298 .protocol = &websocket_stream_p,
299 .locals_dict = (void *)&websocket_locals_dict,
300 };
301
302 STATIC const mp_rom_map_elem_t uwebsocket_module_globals_table[] = {
303 { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_uwebsocket) },
304 { MP_ROM_QSTR(MP_QSTR_websocket), MP_ROM_PTR(&websocket_type) },
305 };
306
307 STATIC MP_DEFINE_CONST_DICT(uwebsocket_module_globals, uwebsocket_module_globals_table);
308
309 const mp_obj_module_t mp_module_uwebsocket = {
310 .base = { &mp_type_module },
311 .globals = (mp_obj_dict_t *)&uwebsocket_module_globals,
312 };
313
314 #endif // MICROPY_PY_UWEBSOCKET
315