1 /*
2 * Copyright (c) 1992, 1993, 1994, 1995, 1996
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 */
21
22 #ifndef EXTRACT_H
23 #define EXTRACT_H
24
25 #include <string.h>
26
27 /*
28 * For 8-bit values; needed to fetch a one-byte value. Byte order
29 * isn't relevant, and alignment isn't an issue.
30 */
31 #define EXTRACT_U_1(p) ((uint8_t)(*(p)))
32 #define EXTRACT_S_1(p) ((int8_t)(*(p)))
33
34 /*
35 * Inline functions or macros to extract possibly-unaligned big-endian
36 * integral values.
37 */
38 #include "funcattrs.h"
39 #include "netdissect.h"
40 #include "diag-control.h"
41
42 /*
43 * If we have versions of GCC or Clang that support an __attribute__
44 * to say "if we're building with unsigned behavior sanitization,
45 * don't complain about undefined behavior in this function", we
46 * label these functions with that attribute - we *know* it's undefined
47 * in the C standard, but we *also* know it does what we want with
48 * the ISA we're targeting and the compiler we're using.
49 *
50 * For GCC 4.9.0 and later, we use __attribute__((no_sanitize_undefined));
51 * pre-5.0 GCC doesn't have __has_attribute, and I'm not sure whether
52 * GCC or Clang first had __attribute__((no_sanitize(XXX)).
53 *
54 * For Clang, we check for __attribute__((no_sanitize(XXX)) with
55 * __has_attribute, as there are versions of Clang that support
56 * __attribute__((no_sanitize("undefined")) but don't support
57 * __attribute__((no_sanitize_undefined)).
58 *
59 * We define this here, rather than in funcattrs.h, because we
60 * only want it used here, we don't want it to be broadly used.
61 * (Any printer will get this defined, but this should at least
62 * make it harder for people to find.)
63 */
64 #if defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 409)
65 #define UNALIGNED_OK __attribute__((no_sanitize_undefined))
66 #elif __has_attribute(no_sanitize)
67 #define UNALIGNED_OK __attribute__((no_sanitize("undefined")))
68 #else
69 #define UNALIGNED_OK
70 #endif
71
72 #if (defined(__i386__) || defined(_M_IX86) || defined(__X86__) || defined(__x86_64__) || defined(_M_X64)) || \
73 (defined(__m68k__) && (!defined(__mc68000__) && !defined(__mc68010__))) || \
74 (defined(__ppc__) || defined(__ppc64__) || defined(_M_PPC) || defined(_ARCH_PPC) || defined(_ARCH_PPC64)) || \
75 (defined(__s390__) || defined(__s390x__) || defined(__zarch__))
76 /*
77 * The processor natively handles unaligned loads, so we can just
78 * cast the pointer and fetch through it.
79 *
80 * XXX - are those all the x86 tests we need?
81 * XXX - are those the only 68k tests we need not to generated
82 * unaligned accesses if the target is the 68000 or 68010?
83 * XXX - are there any tests we don't need, because some definitions are for
84 * compilers that also predefine the GCC symbols?
85 * XXX - do we need to test for both 32-bit and 64-bit versions of those
86 * architectures in all cases?
87 */
88 UNALIGNED_OK static inline uint16_t
EXTRACT_BE_U_2(const void * p)89 EXTRACT_BE_U_2(const void *p)
90 {
91 return ((uint16_t)ntohs(*(const uint16_t *)(p)));
92 }
93
94 UNALIGNED_OK static inline int16_t
EXTRACT_BE_S_2(const void * p)95 EXTRACT_BE_S_2(const void *p)
96 {
97 return ((int16_t)ntohs(*(const int16_t *)(p)));
98 }
99
100 UNALIGNED_OK static inline uint32_t
EXTRACT_BE_U_4(const void * p)101 EXTRACT_BE_U_4(const void *p)
102 {
103 return ((uint32_t)ntohl(*(const uint32_t *)(p)));
104 }
105
106 UNALIGNED_OK static inline int32_t
EXTRACT_BE_S_4(const void * p)107 EXTRACT_BE_S_4(const void *p)
108 {
109 return ((int32_t)ntohl(*(const int32_t *)(p)));
110 }
111
112 UNALIGNED_OK static inline uint64_t
EXTRACT_BE_U_8(const void * p)113 EXTRACT_BE_U_8(const void *p)
114 {
115 return ((uint64_t)(((uint64_t)ntohl(*((const uint32_t *)(p) + 0))) << 32 |
116 ((uint64_t)ntohl(*((const uint32_t *)(p) + 1))) << 0));
117
118 }
119
120 UNALIGNED_OK static inline int64_t
EXTRACT_BE_S_8(const void * p)121 EXTRACT_BE_S_8(const void *p)
122 {
123 return ((int64_t)(((int64_t)ntohl(*((const uint32_t *)(p) + 0))) << 32 |
124 ((uint64_t)ntohl(*((const uint32_t *)(p) + 1))) << 0));
125
126 }
127
128 /*
129 * Extract an IPv4 address, which is in network byte order, and not
130 * necessarily aligned, and provide the result in host byte order.
131 */
132 UNALIGNED_OK static inline uint32_t
EXTRACT_IPV4_TO_HOST_ORDER(const void * p)133 EXTRACT_IPV4_TO_HOST_ORDER(const void *p)
134 {
135 return ((uint32_t)ntohl(*(const uint32_t *)(p)));
136 }
137 #elif ND_IS_AT_LEAST_GNUC_VERSION(2,0) && \
138 (defined(__alpha) || defined(__alpha__) || \
139 defined(__mips) || defined(__mips__))
140 /*
141 * This is MIPS or Alpha, which don't natively handle unaligned loads,
142 * but which have instructions that can help when doing unaligned
143 * loads, and this is GCC 2.0 or later or a compiler that claims to
144 * be GCC 2.0 or later, which we assume that mean we have
145 * __attribute__((packed)), which we can use to convince the compiler
146 * to generate those instructions.
147 *
148 * Declare packed structures containing a uint16_t and a uint32_t,
149 * cast the pointer to point to one of those, and fetch through it;
150 * the GCC manual doesn't appear to explicitly say that
151 * __attribute__((packed)) causes the compiler to generate unaligned-safe
152 * code, but it appears to do so.
153 *
154 * We do this in case the compiler can generate code using those
155 * instructions to do an unaligned load and pass stuff to "ntohs()" or
156 * "ntohl()", which might be better than the code to fetch the
157 * bytes one at a time and assemble them. (That might not be the
158 * case on a little-endian platform, such as DEC's MIPS machines and
159 * Alpha machines, where "ntohs()" and "ntohl()" might not be done
160 * inline.)
161 *
162 * We do this only for specific architectures because, for example,
163 * at least some versions of GCC, when compiling for 64-bit SPARC,
164 * generate code that assumes alignment if we do this.
165 *
166 * XXX - add other architectures and compilers as possible and
167 * appropriate.
168 *
169 * HP's C compiler, indicated by __HP_cc being defined, supports
170 * "#pragma unaligned N" in version A.05.50 and later, where "N"
171 * specifies a number of bytes at which the typedef on the next
172 * line is aligned, e.g.
173 *
174 * #pragma unalign 1
175 * typedef uint16_t unaligned_uint16_t;
176 *
177 * to define unaligned_uint16_t as a 16-bit unaligned data type.
178 * This could be presumably used, in sufficiently recent versions of
179 * the compiler, with macros similar to those below. This would be
180 * useful only if that compiler could generate better code for PA-RISC
181 * or Itanium than would be generated by a bunch of shifts-and-ORs.
182 *
183 * DEC C, indicated by __DECC being defined, has, at least on Alpha,
184 * an __unaligned qualifier that can be applied to pointers to get the
185 * compiler to generate code that does unaligned loads and stores when
186 * dereferencing the pointer in question.
187 *
188 * XXX - what if the native C compiler doesn't support
189 * __attribute__((packed))? How can we get it to generate unaligned
190 * accesses for *specific* items?
191 */
192 typedef struct {
193 uint16_t val;
194 } __attribute__((packed)) unaligned_uint16_t;
195
196 typedef struct {
197 int16_t val;
198 } __attribute__((packed)) unaligned_int16_t;
199
200 typedef struct {
201 uint32_t val;
202 } __attribute__((packed)) unaligned_uint32_t;
203
204 typedef struct {
205 int32_t val;
206 } __attribute__((packed)) unaligned_int32_t;
207
208 UNALIGNED_OK static inline uint16_t
EXTRACT_BE_U_2(const void * p)209 EXTRACT_BE_U_2(const void *p)
210 {
211 return ((uint16_t)ntohs(((const unaligned_uint16_t *)(p))->val));
212 }
213
214 UNALIGNED_OK static inline int16_t
EXTRACT_BE_S_2(const void * p)215 EXTRACT_BE_S_2(const void *p)
216 {
217 return ((int16_t)ntohs(((const unaligned_int16_t *)(p))->val));
218 }
219
220 UNALIGNED_OK static inline uint32_t
EXTRACT_BE_U_4(const void * p)221 EXTRACT_BE_U_4(const void *p)
222 {
223 return ((uint32_t)ntohl(((const unaligned_uint32_t *)(p))->val));
224 }
225
226 UNALIGNED_OK static inline int32_t
EXTRACT_BE_S_4(const void * p)227 EXTRACT_BE_S_4(const void *p)
228 {
229 return ((int32_t)ntohl(((const unaligned_int32_t *)(p))->val));
230 }
231
232 UNALIGNED_OK static inline uint64_t
EXTRACT_BE_U_8(const void * p)233 EXTRACT_BE_U_8(const void *p)
234 {
235 return ((uint64_t)(((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 0)->val)) << 32 |
236 ((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 1)->val)) << 0));
237 }
238
239 UNALIGNED_OK static inline int64_t
EXTRACT_BE_S_8(const void * p)240 EXTRACT_BE_S_8(const void *p)
241 {
242 return ((int64_t)(((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 0)->val)) << 32 |
243 ((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 1)->val)) << 0));
244 }
245
246 /*
247 * Extract an IPv4 address, which is in network byte order, and not
248 * necessarily aligned, and provide the result in host byte order.
249 */
250 UNALIGNED_OK static inline uint32_t
EXTRACT_IPV4_TO_HOST_ORDER(const void * p)251 EXTRACT_IPV4_TO_HOST_ORDER(const void *p)
252 {
253 return ((uint32_t)ntohl(((const unaligned_uint32_t *)(p))->val));
254 }
255 #else
256 /*
257 * This architecture doesn't natively support unaligned loads, and either
258 * this isn't a GCC-compatible compiler, we don't have __attribute__,
259 * or we do but we don't know of any better way with this instruction
260 * set to do unaligned loads, so do unaligned loads of big-endian
261 * quantities the hard way - fetch the bytes one at a time and
262 * assemble them.
263 *
264 * XXX - ARM is a special case. ARMv1 through ARMv5 didn't suppory
265 * unaligned loads; ARMv6 and later support it *but* have a bit in
266 * the system control register that the OS can set and that causes
267 * unaligned loads to fault rather than succeeding.
268 *
269 * At least some OSes may set that flag, so we do *not* treat ARM
270 * as supporting unaligned loads. If your OS supports them on ARM,
271 * and you want to use them, please update the tests in the #if above
272 * to check for ARM *and* for your OS.
273 */
274 #define EXTRACT_BE_U_2(p) \
275 ((uint16_t)(((uint16_t)(*((const uint8_t *)(p) + 0)) << 8) | \
276 ((uint16_t)(*((const uint8_t *)(p) + 1)) << 0)))
277 #define EXTRACT_BE_S_2(p) \
278 ((int16_t)(((uint16_t)(*((const uint8_t *)(p) + 0)) << 8) | \
279 ((uint16_t)(*((const uint8_t *)(p) + 1)) << 0)))
280 #define EXTRACT_BE_U_4(p) \
281 ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 24) | \
282 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 16) | \
283 ((uint32_t)(*((const uint8_t *)(p) + 2)) << 8) | \
284 ((uint32_t)(*((const uint8_t *)(p) + 3)) << 0)))
285 #define EXTRACT_BE_S_4(p) \
286 ((int32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 24) | \
287 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 16) | \
288 ((uint32_t)(*((const uint8_t *)(p) + 2)) << 8) | \
289 ((uint32_t)(*((const uint8_t *)(p) + 3)) << 0)))
290 #define EXTRACT_BE_U_8(p) \
291 ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 56) | \
292 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 48) | \
293 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 40) | \
294 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 32) | \
295 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 24) | \
296 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 16) | \
297 ((uint64_t)(*((const uint8_t *)(p) + 6)) << 8) | \
298 ((uint64_t)(*((const uint8_t *)(p) + 7)) << 0)))
299 #define EXTRACT_BE_S_8(p) \
300 ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 56) | \
301 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 48) | \
302 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 40) | \
303 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 32) | \
304 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 24) | \
305 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 16) | \
306 ((uint64_t)(*((const uint8_t *)(p) + 6)) << 8) | \
307 ((uint64_t)(*((const uint8_t *)(p) + 7)) << 0)))
308
309 /*
310 * Extract an IPv4 address, which is in network byte order, and not
311 * necessarily aligned, and provide the result in host byte order.
312 */
313 #define EXTRACT_IPV4_TO_HOST_ORDER(p) \
314 ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 24) | \
315 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 16) | \
316 ((uint32_t)(*((const uint8_t *)(p) + 2)) << 8) | \
317 ((uint32_t)(*((const uint8_t *)(p) + 3)) << 0)))
318 #endif /* unaligned access checks */
319
320 /*
321 * Extract numerical values in *host* byte order. (Some metadata
322 * headers are in the byte order of the host that wrote the file,
323 * and libpcap translate them to the byte order of the host
324 * reading the file. This means that if a program on that host
325 * reads with libpcap and writes to a new file, the new file will
326 * be written in the byte order of the host writing the file. Thus,
327 * the magic number in pcap files and byte-order magic in pcapng
328 * files can be used to determine the byte order in those metadata
329 * headers.)
330 *
331 * XXX - on platforms that can do unaligned accesses, just cast and
332 * dereference the pointer.
333 */
334 static inline uint16_t
EXTRACT_HE_U_2(const void * p)335 EXTRACT_HE_U_2(const void *p)
336 {
337 uint16_t val;
338
339 UNALIGNED_MEMCPY(&val, p, sizeof(uint16_t));
340 return val;
341 }
342
343 static inline int16_t
EXTRACT_HE_S_2(const void * p)344 EXTRACT_HE_S_2(const void *p)
345 {
346 int16_t val;
347
348 UNALIGNED_MEMCPY(&val, p, sizeof(int16_t));
349 return val;
350 }
351
352 static inline uint32_t
EXTRACT_HE_U_4(const void * p)353 EXTRACT_HE_U_4(const void *p)
354 {
355 uint32_t val;
356
357 UNALIGNED_MEMCPY(&val, p, sizeof(uint32_t));
358 return val;
359 }
360
361 static inline int32_t
EXTRACT_HE_S_4(const void * p)362 EXTRACT_HE_S_4(const void *p)
363 {
364 int32_t val;
365
366 UNALIGNED_MEMCPY(&val, p, sizeof(int32_t));
367 return val;
368 }
369
370 /*
371 * Extract an IPv4 address, which is in network byte order, and which
372 * is not necessarily aligned on a 4-byte boundary, and provide the
373 * result in network byte order.
374 *
375 * This works the same way regardless of the host's byte order.
376 */
377 static inline uint32_t
EXTRACT_IPV4_TO_NETWORK_ORDER(const void * p)378 EXTRACT_IPV4_TO_NETWORK_ORDER(const void *p)
379 {
380 uint32_t addr;
381
382 UNALIGNED_MEMCPY(&addr, p, sizeof(uint32_t));
383 return addr;
384 }
385
386 /*
387 * Non-power-of-2 sizes.
388 */
389 #define EXTRACT_BE_U_3(p) \
390 ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 16) | \
391 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \
392 ((uint32_t)(*((const uint8_t *)(p) + 2)) << 0)))
393
394 #define EXTRACT_BE_S_3(p) \
395 (((*((const uint8_t *)(p) + 0)) & 0x80) ? \
396 ((int32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 16) | \
397 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \
398 ((uint32_t)(*((const uint8_t *)(p) + 2)) << 0))) : \
399 ((int32_t)(0xFF000000U | \
400 ((uint32_t)(*((const uint8_t *)(p) + 0)) << 16) | \
401 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \
402 ((uint32_t)(*((const uint8_t *)(p) + 2)) << 0))))
403
404 #define EXTRACT_BE_U_5(p) \
405 ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 32) | \
406 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 24) | \
407 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \
408 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 8) | \
409 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 0)))
410
411 #define EXTRACT_BE_S_5(p) \
412 (((*((const uint8_t *)(p) + 0)) & 0x80) ? \
413 ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 32) | \
414 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 24) | \
415 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \
416 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 8) | \
417 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 0))) : \
418 ((int64_t)(INT64_T_CONSTANT(0xFFFFFF0000000000U) | \
419 ((uint64_t)(*((const uint8_t *)(p) + 0)) << 32) | \
420 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 24) | \
421 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \
422 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 8) | \
423 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 0))))
424
425 #define EXTRACT_BE_U_6(p) \
426 ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 40) | \
427 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 32) | \
428 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 24) | \
429 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 16) | \
430 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 8) | \
431 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 0)))
432
433 #define EXTRACT_BE_S_6(p) \
434 (((*((const uint8_t *)(p) + 0)) & 0x80) ? \
435 ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 40) | \
436 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 32) | \
437 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 24) | \
438 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 16) | \
439 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 8) | \
440 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 0))) : \
441 ((int64_t)(INT64_T_CONSTANT(0xFFFFFFFF00000000U) | \
442 ((uint64_t)(*((const uint8_t *)(p) + 0)) << 40) | \
443 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 32) | \
444 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 24) | \
445 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 16) | \
446 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 8) | \
447 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 0))))
448
449 #define EXTRACT_BE_U_7(p) \
450 ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 48) | \
451 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 40) | \
452 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 32) | \
453 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \
454 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 16) | \
455 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 8) | \
456 ((uint64_t)(*((const uint8_t *)(p) + 6)) << 0)))
457
458 #define EXTRACT_BE_S_7(p) \
459 (((*((const uint8_t *)(p) + 0)) & 0x80) ? \
460 ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 48) | \
461 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 40) | \
462 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 32) | \
463 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \
464 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 16) | \
465 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 8) | \
466 ((uint64_t)(*((const uint8_t *)(p) + 6)) << 0))) : \
467 ((int64_t)(INT64_T_CONSTANT(0xFFFFFFFFFF000000U) | \
468 ((uint64_t)(*((const uint8_t *)(p) + 0)) << 48) | \
469 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 40) | \
470 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 32) | \
471 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \
472 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 16) | \
473 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 8) | \
474 ((uint64_t)(*((const uint8_t *)(p) + 6)) << 0))))
475
476 /*
477 * Macros to extract possibly-unaligned little-endian integral values.
478 * XXX - do loads on little-endian machines that support unaligned loads?
479 */
480 #define EXTRACT_LE_U_2(p) \
481 ((uint16_t)(((uint16_t)(*((const uint8_t *)(p) + 1)) << 8) | \
482 ((uint16_t)(*((const uint8_t *)(p) + 0)) << 0)))
483 #define EXTRACT_LE_S_2(p) \
484 ((int16_t)(((uint16_t)(*((const uint8_t *)(p) + 1)) << 8) | \
485 ((uint16_t)(*((const uint8_t *)(p) + 0)) << 0)))
486 #define EXTRACT_LE_U_4(p) \
487 ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 3)) << 24) | \
488 ((uint32_t)(*((const uint8_t *)(p) + 2)) << 16) | \
489 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \
490 ((uint32_t)(*((const uint8_t *)(p) + 0)) << 0)))
491 #define EXTRACT_LE_S_4(p) \
492 ((int32_t)(((uint32_t)(*((const uint8_t *)(p) + 3)) << 24) | \
493 ((uint32_t)(*((const uint8_t *)(p) + 2)) << 16) | \
494 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \
495 ((uint32_t)(*((const uint8_t *)(p) + 0)) << 0)))
496 #define EXTRACT_LE_U_8(p) \
497 ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 7)) << 56) | \
498 ((uint64_t)(*((const uint8_t *)(p) + 6)) << 48) | \
499 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 40) | \
500 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 32) | \
501 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \
502 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \
503 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 8) | \
504 ((uint64_t)(*((const uint8_t *)(p) + 0)) << 0)))
505 #define EXTRACT_LE_S_8(p) \
506 ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 7)) << 56) | \
507 ((uint64_t)(*((const uint8_t *)(p) + 6)) << 48) | \
508 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 40) | \
509 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 32) | \
510 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \
511 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \
512 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 8) | \
513 ((uint64_t)(*((const uint8_t *)(p) + 0)) << 0)))
514
515 /*
516 * Non-power-of-2 sizes.
517 */
518
519 #define EXTRACT_LE_U_3(p) \
520 ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 2)) << 16) | \
521 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \
522 ((uint32_t)(*((const uint8_t *)(p) + 0)) << 0)))
523 #define EXTRACT_LE_S_3(p) \
524 ((int32_t)(((uint32_t)(*((const uint8_t *)(p) + 2)) << 16) | \
525 ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \
526 ((uint32_t)(*((const uint8_t *)(p) + 0)) << 0)))
527 #define EXTRACT_LE_U_5(p) \
528 ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 4)) << 32) | \
529 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \
530 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \
531 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 8) | \
532 ((uint64_t)(*((const uint8_t *)(p) + 0)) << 0)))
533 #define EXTRACT_LE_U_6(p) \
534 ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 5)) << 40) | \
535 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 32) | \
536 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \
537 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \
538 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 8) | \
539 ((uint64_t)(*((const uint8_t *)(p) + 0)) << 0)))
540 #define EXTRACT_LE_U_7(p) \
541 ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 6)) << 48) | \
542 ((uint64_t)(*((const uint8_t *)(p) + 5)) << 40) | \
543 ((uint64_t)(*((const uint8_t *)(p) + 4)) << 32) | \
544 ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \
545 ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \
546 ((uint64_t)(*((const uint8_t *)(p) + 1)) << 8) | \
547 ((uint64_t)(*((const uint8_t *)(p) + 0)) << 0)))
548
549 /*
550 * Macros to check the presence of the values in question.
551 */
552 #define ND_TTEST_1(p) ND_TTEST_LEN((p), 1)
553 #define ND_TCHECK_1(p) ND_TCHECK_LEN((p), 1)
554
555 #define ND_TTEST_2(p) ND_TTEST_LEN((p), 2)
556 #define ND_TCHECK_2(p) ND_TCHECK_LEN((p), 2)
557
558 #define ND_TTEST_3(p) ND_TTEST_LEN((p), 3)
559 #define ND_TCHECK_3(p) ND_TCHECK_LEN((p), 3)
560
561 #define ND_TTEST_4(p) ND_TTEST_LEN((p), 4)
562 #define ND_TCHECK_4(p) ND_TCHECK_LEN((p), 4)
563
564 #define ND_TTEST_5(p) ND_TTEST_LEN((p), 5)
565 #define ND_TCHECK_5(p) ND_TCHECK_LEN((p), 5)
566
567 #define ND_TTEST_6(p) ND_TTEST_LEN((p), 6)
568 #define ND_TCHECK_6(p) ND_TCHECK_LEN((p), 6)
569
570 #define ND_TTEST_7(p) ND_TTEST_LEN((p), 7)
571 #define ND_TCHECK_7(p) ND_TCHECK_LEN((p), 7)
572
573 #define ND_TTEST_8(p) ND_TTEST_LEN((p), 8)
574 #define ND_TCHECK_8(p) ND_TCHECK_LEN((p), 8)
575
576 #define ND_TTEST_16(p) ND_TTEST_LEN((p), 16)
577 #define ND_TCHECK_16(p) ND_TCHECK_LEN((p), 16)
578
579 /* get_u_1 and get_s_1 */
580
581 static inline uint8_t
get_u_1(netdissect_options * ndo,const u_char * p)582 get_u_1(netdissect_options *ndo, const u_char *p)
583 {
584 if (!ND_TTEST_1(p))
585 nd_trunc_longjmp(ndo);
586 return EXTRACT_U_1(p);
587 }
588
589 static inline int8_t
get_s_1(netdissect_options * ndo,const u_char * p)590 get_s_1(netdissect_options *ndo, const u_char *p)
591 {
592 if (!ND_TTEST_1(p))
593 nd_trunc_longjmp(ndo);
594 return EXTRACT_S_1(p);
595 }
596
597 /* get_be_u_N */
598
599 static inline uint16_t
get_be_u_2(netdissect_options * ndo,const u_char * p)600 get_be_u_2(netdissect_options *ndo, const u_char *p)
601 {
602 if (!ND_TTEST_2(p))
603 nd_trunc_longjmp(ndo);
604 return EXTRACT_BE_U_2(p);
605 }
606
607 static inline uint32_t
get_be_u_3(netdissect_options * ndo,const u_char * p)608 get_be_u_3(netdissect_options *ndo, const u_char *p)
609 {
610 if (!ND_TTEST_3(p))
611 nd_trunc_longjmp(ndo);
612 return EXTRACT_BE_U_3(p);
613 }
614
615 static inline uint32_t
get_be_u_4(netdissect_options * ndo,const u_char * p)616 get_be_u_4(netdissect_options *ndo, const u_char *p)
617 {
618 if (!ND_TTEST_4(p))
619 nd_trunc_longjmp(ndo);
620 return EXTRACT_BE_U_4(p);
621 }
622
623 static inline uint64_t
get_be_u_5(netdissect_options * ndo,const u_char * p)624 get_be_u_5(netdissect_options *ndo, const u_char *p)
625 {
626 if (!ND_TTEST_5(p))
627 nd_trunc_longjmp(ndo);
628 return EXTRACT_BE_U_5(p);
629 }
630
631 static inline uint64_t
get_be_u_6(netdissect_options * ndo,const u_char * p)632 get_be_u_6(netdissect_options *ndo, const u_char *p)
633 {
634 if (!ND_TTEST_6(p))
635 nd_trunc_longjmp(ndo);
636 return EXTRACT_BE_U_6(p);
637 }
638
639 static inline uint64_t
get_be_u_7(netdissect_options * ndo,const u_char * p)640 get_be_u_7(netdissect_options *ndo, const u_char *p)
641 {
642 if (!ND_TTEST_7(p))
643 nd_trunc_longjmp(ndo);
644 return EXTRACT_BE_U_7(p);
645 }
646
647 static inline uint64_t
get_be_u_8(netdissect_options * ndo,const u_char * p)648 get_be_u_8(netdissect_options *ndo, const u_char *p)
649 {
650 if (!ND_TTEST_8(p))
651 nd_trunc_longjmp(ndo);
652 return EXTRACT_BE_U_8(p);
653 }
654
655 /* get_be_s_N */
656
657 static inline int16_t
get_be_s_2(netdissect_options * ndo,const u_char * p)658 get_be_s_2(netdissect_options *ndo, const u_char *p)
659 {
660 if (!ND_TTEST_2(p))
661 nd_trunc_longjmp(ndo);
662 return EXTRACT_BE_S_2(p);
663 }
664
665 static inline int32_t
get_be_s_3(netdissect_options * ndo,const u_char * p)666 get_be_s_3(netdissect_options *ndo, const u_char *p)
667 {
668 if (!ND_TTEST_3(p))
669 nd_trunc_longjmp(ndo);
670 return EXTRACT_BE_S_3(p);
671 }
672
673 static inline int32_t
get_be_s_4(netdissect_options * ndo,const u_char * p)674 get_be_s_4(netdissect_options *ndo, const u_char *p)
675 {
676 if (!ND_TTEST_4(p))
677 nd_trunc_longjmp(ndo);
678 return EXTRACT_BE_S_4(p);
679 }
680
681 static inline int64_t
get_be_s_5(netdissect_options * ndo,const u_char * p)682 get_be_s_5(netdissect_options *ndo, const u_char *p)
683 {
684 if (!ND_TTEST_5(p))
685 nd_trunc_longjmp(ndo);
686 return EXTRACT_BE_S_5(p);
687 }
688
689 static inline int64_t
get_be_s_6(netdissect_options * ndo,const u_char * p)690 get_be_s_6(netdissect_options *ndo, const u_char *p)
691 {
692 if (!ND_TTEST_6(p))
693 nd_trunc_longjmp(ndo);
694 return EXTRACT_BE_S_6(p);
695 }
696
697 static inline int64_t
get_be_s_7(netdissect_options * ndo,const u_char * p)698 get_be_s_7(netdissect_options *ndo, const u_char *p)
699 {
700 if (!ND_TTEST_7(p))
701 nd_trunc_longjmp(ndo);
702 return EXTRACT_BE_S_7(p);
703 }
704
705 static inline int64_t
get_be_s_8(netdissect_options * ndo,const u_char * p)706 get_be_s_8(netdissect_options *ndo, const u_char *p)
707 {
708 if (!ND_TTEST_8(p))
709 nd_trunc_longjmp(ndo);
710 return EXTRACT_BE_S_8(p);
711 }
712
713 /* get_he_u_N */
714
715 static inline uint16_t
get_he_u_2(netdissect_options * ndo,const u_char * p)716 get_he_u_2(netdissect_options *ndo, const u_char *p)
717 {
718 if (!ND_TTEST_2(p))
719 nd_trunc_longjmp(ndo);
720 return EXTRACT_HE_U_2(p);
721 }
722
723 static inline uint32_t
get_he_u_4(netdissect_options * ndo,const u_char * p)724 get_he_u_4(netdissect_options *ndo, const u_char *p)
725 {
726 if (!ND_TTEST_4(p))
727 nd_trunc_longjmp(ndo);
728 return EXTRACT_HE_U_4(p);
729 }
730
731 /* get_he_s_N */
732
733 static inline int16_t
get_he_s_2(netdissect_options * ndo,const u_char * p)734 get_he_s_2(netdissect_options *ndo, const u_char *p)
735 {
736 if (!ND_TTEST_2(p))
737 nd_trunc_longjmp(ndo);
738 return EXTRACT_HE_S_2(p);
739 }
740
741 static inline int32_t
get_he_s_4(netdissect_options * ndo,const u_char * p)742 get_he_s_4(netdissect_options *ndo, const u_char *p)
743 {
744 if (!ND_TTEST_4(p))
745 nd_trunc_longjmp(ndo);
746 return EXTRACT_HE_S_4(p);
747 }
748
749 /* get_le_u_N */
750
751 static inline uint16_t
get_le_u_2(netdissect_options * ndo,const u_char * p)752 get_le_u_2(netdissect_options *ndo, const u_char *p)
753 {
754 if (!ND_TTEST_2(p))
755 nd_trunc_longjmp(ndo);
756 return EXTRACT_LE_U_2(p);
757 }
758
759 static inline uint32_t
get_le_u_3(netdissect_options * ndo,const u_char * p)760 get_le_u_3(netdissect_options *ndo, const u_char *p)
761 {
762 if (!ND_TTEST_3(p))
763 nd_trunc_longjmp(ndo);
764 return EXTRACT_LE_U_3(p);
765 }
766
767 static inline uint32_t
get_le_u_4(netdissect_options * ndo,const u_char * p)768 get_le_u_4(netdissect_options *ndo, const u_char *p)
769 {
770 if (!ND_TTEST_4(p))
771 nd_trunc_longjmp(ndo);
772 return EXTRACT_LE_U_4(p);
773 }
774
775 static inline uint64_t
get_le_u_5(netdissect_options * ndo,const u_char * p)776 get_le_u_5(netdissect_options *ndo, const u_char *p)
777 {
778 if (!ND_TTEST_5(p))
779 nd_trunc_longjmp(ndo);
780 return EXTRACT_LE_U_5(p);
781 }
782
783 static inline uint64_t
get_le_u_6(netdissect_options * ndo,const u_char * p)784 get_le_u_6(netdissect_options *ndo, const u_char *p)
785 {
786 if (!ND_TTEST_6(p))
787 nd_trunc_longjmp(ndo);
788 return EXTRACT_LE_U_6(p);
789 }
790
791 static inline uint64_t
get_le_u_7(netdissect_options * ndo,const u_char * p)792 get_le_u_7(netdissect_options *ndo, const u_char *p)
793 {
794 if (!ND_TTEST_7(p))
795 nd_trunc_longjmp(ndo);
796 return EXTRACT_LE_U_7(p);
797 }
798
799 static inline uint64_t
get_le_u_8(netdissect_options * ndo,const u_char * p)800 get_le_u_8(netdissect_options *ndo, const u_char *p)
801 {
802 if (!ND_TTEST_8(p))
803 nd_trunc_longjmp(ndo);
804 return EXTRACT_LE_U_8(p);
805 }
806
807 /* get_le_s_N */
808
809 static inline int16_t
get_le_s_2(netdissect_options * ndo,const u_char * p)810 get_le_s_2(netdissect_options *ndo, const u_char *p)
811 {
812 if (!ND_TTEST_2(p))
813 nd_trunc_longjmp(ndo);
814 return EXTRACT_LE_S_2(p);
815 }
816
817 static inline int32_t
get_le_s_3(netdissect_options * ndo,const u_char * p)818 get_le_s_3(netdissect_options *ndo, const u_char *p)
819 {
820 if (!ND_TTEST_3(p))
821 nd_trunc_longjmp(ndo);
822 return EXTRACT_LE_S_3(p);
823 }
824
825 static inline int32_t
get_le_s_4(netdissect_options * ndo,const u_char * p)826 get_le_s_4(netdissect_options *ndo, const u_char *p)
827 {
828 if (!ND_TTEST_4(p))
829 nd_trunc_longjmp(ndo);
830 return EXTRACT_LE_S_4(p);
831 }
832
833 static inline int64_t
get_le_s_8(netdissect_options * ndo,const u_char * p)834 get_le_s_8(netdissect_options *ndo, const u_char *p)
835 {
836 if (!ND_TTEST_8(p))
837 nd_trunc_longjmp(ndo);
838 return EXTRACT_LE_S_8(p);
839 }
840
841 /* get_ipv4_to_{host|network]_order */
842
843 static inline uint32_t
get_ipv4_to_host_order(netdissect_options * ndo,const u_char * p)844 get_ipv4_to_host_order(netdissect_options *ndo, const u_char *p)
845 {
846 if (!ND_TTEST_4(p))
847 nd_trunc_longjmp(ndo);
848 return EXTRACT_IPV4_TO_HOST_ORDER(p);
849 }
850
851 static inline uint32_t
get_ipv4_to_network_order(netdissect_options * ndo,const u_char * p)852 get_ipv4_to_network_order(netdissect_options *ndo, const u_char *p)
853 {
854 if (!ND_TTEST_4(p))
855 nd_trunc_longjmp(ndo);
856 return EXTRACT_IPV4_TO_NETWORK_ORDER(p);
857 }
858
859 static inline void
get_cpy_bytes(netdissect_options * ndo,u_char * dst,const u_char * p,size_t len)860 get_cpy_bytes(netdissect_options *ndo, u_char *dst, const u_char *p, size_t len)
861 {
862 if (!ND_TTEST_LEN(p, len))
863 nd_trunc_longjmp(ndo);
864 UNALIGNED_MEMCPY(dst, p, len);
865 }
866
867 #define GET_U_1(p) get_u_1(ndo, (const u_char *)(p))
868 #define GET_S_1(p) get_s_1(ndo, (const u_char *)(p))
869
870 #define GET_BE_U_2(p) get_be_u_2(ndo, (const u_char *)(p))
871 #define GET_BE_U_3(p) get_be_u_3(ndo, (const u_char *)(p))
872 #define GET_BE_U_4(p) get_be_u_4(ndo, (const u_char *)(p))
873 #define GET_BE_U_5(p) get_be_u_5(ndo, (const u_char *)(p))
874 #define GET_BE_U_6(p) get_be_u_6(ndo, (const u_char *)(p))
875 #define GET_BE_U_7(p) get_be_u_7(ndo, (const u_char *)(p))
876 #define GET_BE_U_8(p) get_be_u_8(ndo, (const u_char *)(p))
877
878 #define GET_BE_S_2(p) get_be_s_2(ndo, (const u_char *)(p))
879 #define GET_BE_S_3(p) get_be_s_3(ndo, (const u_char *)(p))
880 #define GET_BE_S_4(p) get_be_s_4(ndo, (const u_char *)(p))
881 #define GET_BE_S_5(p) get_be_s_5(ndo, (const u_char *)(p))
882 #define GET_BE_S_6(p) get_be_s_6(ndo, (const u_char *)(p))
883 #define GET_BE_S_7(p) get_be_s_7(ndo, (const u_char *)(p))
884 #define GET_BE_S_8(p) get_be_s_8(ndo, (const u_char *)(p))
885
886 #define GET_HE_U_2(p) get_he_u_2(ndo, (const u_char *)(p))
887 #define GET_HE_U_4(p) get_he_u_4(ndo, (const u_char *)(p))
888
889 #define GET_HE_S_2(p) get_he_s_2(ndo, (const u_char *)(p))
890 #define GET_HE_S_4(p) get_he_s_4(ndo, (const u_char *)(p))
891
892 #define GET_LE_U_2(p) get_le_u_2(ndo, (const u_char *)(p))
893 #define GET_LE_U_3(p) get_le_u_3(ndo, (const u_char *)(p))
894 #define GET_LE_U_4(p) get_le_u_4(ndo, (const u_char *)(p))
895 #define GET_LE_U_5(p) get_le_u_5(ndo, (const u_char *)(p))
896 #define GET_LE_U_6(p) get_le_u_6(ndo, (const u_char *)(p))
897 #define GET_LE_U_7(p) get_le_u_7(ndo, (const u_char *)(p))
898 #define GET_LE_U_8(p) get_le_u_8(ndo, (const u_char *)(p))
899
900 #define GET_LE_S_2(p) get_le_s_2(ndo, (const u_char *)(p))
901 #define GET_LE_S_3(p) get_le_s_3(ndo, (const u_char *)(p))
902 #define GET_LE_S_4(p) get_le_s_4(ndo, (const u_char *)(p))
903 #define GET_LE_S_8(p) get_le_s_8(ndo, (const u_char *)(p))
904
905 #define GET_IPV4_TO_HOST_ORDER(p) get_ipv4_to_host_order(ndo, (const u_char *)(p))
906 #define GET_IPV4_TO_NETWORK_ORDER(p) get_ipv4_to_network_order(ndo, (const u_char *)(p))
907
908 #define GET_CPY_BYTES(dst, p, len) get_cpy_bytes(ndo, (u_char *)(dst), (const u_char *)(p), len)
909
910 #endif /* EXTRACT_H */
911