/
frame_parser.c
400 lines (335 loc) · 14.7 KB
/
frame_parser.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
/*
* nghq
*
* Copyright (c) 2018 British Broadcasting Corporation
*
* 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 <string.h>
#include <stdlib.h>
#include <arpa/inet.h>
#include "frame_parser.h"
#include "header_compression.h"
#include "util.h"
#include "debug.h"
/*
* Parse the frame header - returns the length of the frame payload, excluding
* the generic H3 header itself.
*/
static uint64_t _get_frame_payload_length (uint8_t* buf, nghq_frame_type *type,
size_t *header_offset) {
*header_offset = 0;
nghq_frame_type t = _get_varlen_int(buf, header_offset, 16);
if (type != NULL) *type = t;
return _get_varlen_int(buf + *header_offset, header_offset, 16);
}
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Length (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
ssize_t parse_frame_header (nghq_io_buf* buf, nghq_frame_type *type) {
uint64_t frame_length = 0;
size_t header_offset = 0;
if (buf == NULL) return 0;
*type = _get_varlen_int(buf->send_pos, &header_offset, 16);
frame_length = _get_varlen_int(buf->send_pos + header_offset, &header_offset, 16);
if (*type < NGHQ_FRAME_TYPE_DATA || *type > NGHQ_FRAME_TYPE_MAX_PUSH_ID) {
return NGHQ_ERROR;
}
return frame_length + header_offset;
}
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type (i) ... Frame
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Header
* | Length (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ===========
* | Data (*) | DATA
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Payload
*/
ssize_t parse_data_frame (nghq_session *session, nghq_io_buf* buf,
uint8_t** data, size_t *data_len) {
size_t header_len;
nghq_frame_type frame_type;
*data_len = (size_t) _get_frame_payload_length(buf->send_pos, &frame_type,
&header_len);
if (frame_type != NGHQ_FRAME_TYPE_DATA) {
return NGHQ_ERROR;
}
*data = buf->send_pos + header_len;
buf->send_pos += *data_len + header_len;
buf->remaining -= *data_len + header_len;
NGHQ_LOG_DEBUG (session, "Received DATA frame of length %lu\n", *data_len);
return 0;
}
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type (i) ... Frame
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Header
* | Length (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ===========
* | Encoded Field Section (*) | HEADERS
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Payload
*/
ssize_t parse_headers_frame (nghq_session *session,
nghq_hdr_compression_ctx* ctx, nghq_io_buf* buf,
nghq_header*** hdrs, size_t* num_hdrs) {
size_t header_len = 0, expected_header_block_len;
ssize_t result;
nghq_frame_type type;
expected_header_block_len =
_get_frame_payload_length(buf->send_pos, &type, &header_len);
if (type != NGHQ_FRAME_TYPE_HEADERS) {
return NGHQ_ERROR;
}
if (expected_header_block_len + header_len > buf->remaining) {
return expected_header_block_len + header_len;
}
result = nghq_inflate_hdr(session, ctx, buf->send_pos + header_len,
expected_header_block_len, 1, hdrs, num_hdrs);
if (result < 0) return result;
buf->send_pos += expected_header_block_len + header_len;
buf->remaining -= expected_header_block_len + header_len;
NGHQ_LOG_DEBUG (session, "Received HEADERS frame of length %lu with %lu "
"headers\n", expected_header_block_len, *num_hdrs);
return 0;
}
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type (i) ... Frame
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Header
* | Length (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ===========
* | Push ID (i) ... CANCEL_PUSH
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Payload
*/
int parse_cancel_push_frame (nghq_session *session, nghq_io_buf* buf,
uint64_t* push_id) {
size_t off = 0;
nghq_frame_type type;
uint64_t frame_length = _get_frame_payload_length(buf->send_pos, &type, &off);
if (type != NGHQ_FRAME_TYPE_CANCEL_PUSH) {
return NGHQ_ERROR;
}
frame_length += off;
if (buf->remaining < frame_length) {
return frame_length;
}
*push_id = _get_varlen_int(buf->send_pos+off, &off, frame_length);
if (off > frame_length) {
return NGHQ_HTTP_MALFORMED_FRAME;
}
buf->send_pos += frame_length;
buf->remaining -= frame_length;
NGHQ_LOG_DEBUG (session, "Received CANCEL_PUSH frame for push ID %lu\n",
*push_id);
return NGHQ_OK;
}
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type (i) ... Frame
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Header
* | Length (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ===========
* | Identifier (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Value (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | [Identifier (i)] ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | [Value (i)] ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | [...] |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
int parse_settings_frame (nghq_session *session, nghq_io_buf* buf,
nghq_settings** settings) {
size_t off = 0;
nghq_frame_type type;
uint64_t frame_length;
int rv = NGHQ_OK;
int seen_max_header_list_size = 0;
int seen_num_placeholders = 0;
frame_length = _get_frame_payload_length(buf->send_pos, &type, &off);
if (type != NGHQ_FRAME_TYPE_SETTINGS) {
return NGHQ_ERROR;
}
frame_length += off;
if (buf->remaining < frame_length) {
return frame_length;
}
if (*settings == NULL) {
*settings = malloc(sizeof(nghq_settings));
if (*settings == NULL) {
return NGHQ_OUT_OF_MEMORY;
}
(*settings)->max_header_list_size =
NGHQ_SETTINGS_DEFAULT_MAX_HEADER_LIST_SIZE;
(*settings)->number_of_placeholders =
NGHQ_SETTINGS_DEFAULT_NUM_PLACEHOLDERS;
}
while (rv == NGHQ_OK && off < frame_length) {
uint64_t id = _get_varlen_int(buf->send_pos + off, &off, frame_length);
uint64_t value = _get_varlen_int(buf->send_pos + off, &off, frame_length);
switch (id) {
case NGHQ_SETTINGS_MAX_HEADER_LIST_SIZE:
if (seen_max_header_list_size++) {
rv = NGHQ_HTTP_MALFORMED_FRAME;
} else {
(*settings)->max_header_list_size = value;
}
break;
case NGHQ_SETTINGS_NUM_PLACEHOLDERS:
if (seen_num_placeholders++) {
rv = NGHQ_HTTP_MALFORMED_FRAME;
} else {
(*settings)->number_of_placeholders = value;
}
}
}
if (rv == NGHQ_OK) {
buf->send_pos += frame_length;
buf->remaining -= frame_length;
}
return rv;
}
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type (i) ... Frame
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Header
* | Length (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ===========
* | Push ID (i) ... PUSH_
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ PROMISE
* | Encoded Field Section (*) ... Payload
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
ssize_t parse_push_promise_frame (nghq_session *session,
nghq_hdr_compression_ctx *ctx,
nghq_io_buf* buf, uint64_t* push_id,
nghq_header ***hdrs, size_t* num_hdrs) {
size_t push_header_len = 0, push_id_len = 0, frame_payload_len;
ssize_t result;
nghq_frame_type type;
frame_payload_len =
_get_frame_payload_length(buf->send_pos, &type, &push_header_len);
if (type != NGHQ_FRAME_TYPE_PUSH_PROMISE) {
return NGHQ_ERROR;
}
if (buf->remaining < push_header_len + frame_payload_len) {
return push_header_len + frame_payload_len;
}
*push_id = _get_varlen_int(buf->send_pos + push_header_len, &push_id_len, push_header_len + frame_payload_len);
if (push_id_len > push_header_len + frame_payload_len) {
return NGHQ_HTTP_MALFORMED_FRAME;
}
result = nghq_inflate_hdr(session, ctx,
buf->send_pos + push_header_len + push_id_len,
frame_payload_len - push_id_len, 1, hdrs,
num_hdrs);
if (result == NGHQ_OK) {
buf->send_pos += push_header_len + frame_payload_len;
buf->remaining -= push_header_len + frame_payload_len;
}
NGHQ_LOG_DEBUG (session, "Received PUSH_PROMISE frame for push ID %lu with "
"%lu headers\n", *push_id, *num_hdrs);
return result;
}
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type (i) ... Frame
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Header
* | Length (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ===========
* | Stream ID (i) ... GOAWAY
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Payload
*/
int parse_goaway_frame (nghq_session *session, nghq_io_buf* buf,
uint64_t* last_stream_id) {
size_t off = 0;
nghq_frame_type type;
uint64_t frame_length = _get_frame_payload_length(buf->send_pos, &type, &off);
if (type != NGHQ_FRAME_TYPE_GOAWAY) {
return NGHQ_ERROR;
}
frame_length += off;
if (buf->remaining < frame_length) {
return frame_length;
}
*last_stream_id = _get_varlen_int(buf->send_pos + off, &off, frame_length);
if (off > frame_length) {
return NGHQ_HTTP_MALFORMED_FRAME;
}
buf->send_pos += frame_length;
buf->remaining -= frame_length;
NGHQ_LOG_DEBUG (session, "Received GOAWAY frame with last stream ID %lu\n",
*last_stream_id);
return NGHQ_OK;
}
/*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type (i) ... Frame
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Header
* | Length (i) ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ===========
* | Maximum Push ID (i) ... MAX_PUSH_ID
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Payload
*/
int parse_max_push_id_frame (nghq_session *session, nghq_io_buf* buf,
uint64_t* max_push_id) {
size_t off = 0;
nghq_frame_type type;
uint64_t frame_length = _get_frame_payload_length(buf->send_pos, &type, &off);
if (type != NGHQ_FRAME_TYPE_MAX_PUSH_ID) {
return NGHQ_ERROR;
}
frame_length += off;
if (buf->remaining < frame_length) {
return frame_length;
}
*max_push_id = _get_varlen_int(buf->send_pos + off, &off, frame_length);
if (off > frame_length) {
return NGHQ_HTTP_MALFORMED_FRAME;
}
buf->send_pos += frame_length;
buf->remaining -= frame_length;
NGHQ_LOG_DEBUG (session, "Received MAX_PUSH_ID frame with max push ID %lu\n",
*max_push_id);
return NGHQ_OK;
}