xref: /freebsd/contrib/tcpdump/extract.h (revision aa1a8ff2d6dbc51ef058f46f3db5a8bb77967145)
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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