NCBI C++ ToolKit
common.h
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1 /**
2  * \file common.h
3  *
4  * \brief Utility macros for internal use in the library
5  */
6 /*
7  * Copyright The Mbed TLS Contributors
8  * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
9  */
10 
11 #ifndef MBEDTLS_LIBRARY_COMMON_H
12 #define MBEDTLS_LIBRARY_COMMON_H
13 
14 #include "mbedtls/build_info.h"
15 #include "alignment.h"
16 
17 #include <assert.h>
18 #include <stddef.h>
19 #include <stdint.h>
20 #include <stddef.h>
21 
22 #if defined(__ARM_NEON)
23 #include <arm_neon.h>
24 #define MBEDTLS_HAVE_NEON_INTRINSICS
25 #elif defined(MBEDTLS_PLATFORM_IS_WINDOWS_ON_ARM64)
26 #include <arm64_neon.h>
27 #define MBEDTLS_HAVE_NEON_INTRINSICS
28 #endif
29 
30 /** Helper to define a function as static except when building invasive tests.
31  *
32  * If a function is only used inside its own source file and should be
33  * declared `static` to allow the compiler to optimize for code size,
34  * but that function has unit tests, define it with
35  * ```
36  * MBEDTLS_STATIC_TESTABLE int mbedtls_foo(...) { ... }
37  * ```
38  * and declare it in a header in the `library/` directory with
39  * ```
40  * #if defined(MBEDTLS_TEST_HOOKS)
41  * int mbedtls_foo(...);
42  * #endif
43  * ```
44  */
45 #if defined(MBEDTLS_TEST_HOOKS)
46 #define MBEDTLS_STATIC_TESTABLE
47 #else
48 #define MBEDTLS_STATIC_TESTABLE static
49 #endif
50 
51 #if defined(MBEDTLS_TEST_HOOKS)
52 extern void (*mbedtls_test_hook_test_fail)(const char *test, int line, const char *file);
53 #define MBEDTLS_TEST_HOOK_TEST_ASSERT(TEST) \
54  do { \
55  if ((!(TEST)) && ((*mbedtls_test_hook_test_fail) != NULL)) \
56  { \
57  (*mbedtls_test_hook_test_fail)( #TEST, __LINE__, __FILE__); \
58  } \
59  } while (0)
60 #else
61 #define MBEDTLS_TEST_HOOK_TEST_ASSERT(TEST)
62 #endif /* defined(MBEDTLS_TEST_HOOKS) */
63 
64 /** \def ARRAY_LENGTH
65  * Return the number of elements of a static or stack array.
66  *
67  * \param array A value of array (not pointer) type.
68  *
69  * \return The number of elements of the array.
70  */
71 /* A correct implementation of ARRAY_LENGTH, but which silently gives
72  * a nonsensical result if called with a pointer rather than an array. */
73 #define ARRAY_LENGTH_UNSAFE(array) \
74  (sizeof(array) / sizeof(*(array)))
75 
76 #if defined(__GNUC__)
77 /* Test if arg and &(arg)[0] have the same type. This is true if arg is
78  * an array but not if it's a pointer. */
79 #define IS_ARRAY_NOT_POINTER(arg) \
80  (!__builtin_types_compatible_p(__typeof__(arg), \
81  __typeof__(&(arg)[0])))
82 /* A compile-time constant with the value 0. If `const_expr` is not a
83  * compile-time constant with a nonzero value, cause a compile-time error. */
84 #define STATIC_ASSERT_EXPR(const_expr) \
85  (0 && sizeof(struct { unsigned int STATIC_ASSERT : 1 - 2 * !(const_expr); }))
86 
87 /* Return the scalar value `value` (possibly promoted). This is a compile-time
88  * constant if `value` is. `condition` must be a compile-time constant.
89  * If `condition` is false, arrange to cause a compile-time error. */
90 #define STATIC_ASSERT_THEN_RETURN(condition, value) \
91  (STATIC_ASSERT_EXPR(condition) ? 0 : (value))
92 
93 #define ARRAY_LENGTH(array) \
94  (STATIC_ASSERT_THEN_RETURN(IS_ARRAY_NOT_POINTER(array), \
95  ARRAY_LENGTH_UNSAFE(array)))
96 
97 #else
98 /* If we aren't sure the compiler supports our non-standard tricks,
99  * fall back to the unsafe implementation. */
100 #define ARRAY_LENGTH(array) ARRAY_LENGTH_UNSAFE(array)
101 #endif
102 /** Allow library to access its structs' private members.
103  *
104  * Although structs defined in header files are publicly available,
105  * their members are private and should not be accessed by the user.
106  */
107 #define MBEDTLS_ALLOW_PRIVATE_ACCESS
108 
109 /**
110  * \brief Securely zeroize a buffer then free it.
111  *
112  * Similar to making consecutive calls to
113  * \c mbedtls_platform_zeroize() and \c mbedtls_free(), but has
114  * code size savings, and potential for optimisation in the future.
115  *
116  * Guaranteed to be a no-op if \p buf is \c NULL and \p len is 0.
117  *
118  * \param buf Buffer to be zeroized then freed.
119  * \param len Length of the buffer in bytes
120  */
121 void mbedtls_zeroize_and_free(void *buf, size_t len);
122 
123 /** Return an offset into a buffer.
124  *
125  * This is just the addition of an offset to a pointer, except that this
126  * function also accepts an offset of 0 into a buffer whose pointer is null.
127  * (`p + n` has undefined behavior when `p` is null, even when `n == 0`.
128  * A null pointer is a valid buffer pointer when the size is 0, for example
129  * as the result of `malloc(0)` on some platforms.)
130  *
131  * \param p Pointer to a buffer of at least n bytes.
132  * This may be \p NULL if \p n is zero.
133  * \param n An offset in bytes.
134  * \return Pointer to offset \p n in the buffer \p p.
135  * Note that this is only a valid pointer if the size of the
136  * buffer is at least \p n + 1.
137  */
138 static inline unsigned char *mbedtls_buffer_offset(
139  unsigned char *p, size_t n)
140 {
141  return p == NULL ? NULL : p + n;
142 }
143 
144 /** Return an offset into a read-only buffer.
145  *
146  * Similar to mbedtls_buffer_offset(), but for const pointers.
147  *
148  * \param p Pointer to a buffer of at least n bytes.
149  * This may be \p NULL if \p n is zero.
150  * \param n An offset in bytes.
151  * \return Pointer to offset \p n in the buffer \p p.
152  * Note that this is only a valid pointer if the size of the
153  * buffer is at least \p n + 1.
154  */
155 static inline const unsigned char *mbedtls_buffer_offset_const(
156  const unsigned char *p, size_t n)
157 {
158  return p == NULL ? NULL : p + n;
159 }
160 
161 /* Always inline mbedtls_xor() for similar reasons as mbedtls_xor_no_simd(). */
162 #if defined(__IAR_SYSTEMS_ICC__)
163 #pragma inline = forced
164 #elif defined(__GNUC__)
165 __attribute__((always_inline))
166 #endif
167 /**
168  * Perform a fast block XOR operation, such that
169  * r[i] = a[i] ^ b[i] where 0 <= i < n
170  *
171  * \param r Pointer to result (buffer of at least \p n bytes). \p r
172  * may be equal to either \p a or \p b, but behaviour when
173  * it overlaps in other ways is undefined.
174  * \param a Pointer to input (buffer of at least \p n bytes)
175  * \param b Pointer to input (buffer of at least \p n bytes)
176  * \param n Number of bytes to process.
177  *
178  * \note Depending on the situation, it may be faster to use either mbedtls_xor() or
179  * mbedtls_xor_no_simd() (these are functionally equivalent).
180  * If the result is used immediately after the xor operation in non-SIMD code (e.g, in
181  * AES-CBC), there may be additional latency to transfer the data from SIMD to scalar
182  * registers, and in this case, mbedtls_xor_no_simd() may be faster. In other cases where
183  * the result is not used immediately (e.g., in AES-CTR), mbedtls_xor() may be faster.
184  * For targets without SIMD support, they will behave the same.
185  */
186 static inline void mbedtls_xor(unsigned char *r,
187  const unsigned char *a,
188  const unsigned char *b,
189  size_t n)
190 {
191  size_t i = 0;
192 #if defined(MBEDTLS_EFFICIENT_UNALIGNED_ACCESS)
193 #if defined(MBEDTLS_HAVE_NEON_INTRINSICS) && \
194  (!(defined(MBEDTLS_COMPILER_IS_GCC) && MBEDTLS_GCC_VERSION < 70300))
195  /* Old GCC versions generate a warning here, so disable the NEON path for these compilers */
196  for (; (i + 16) <= n; i += 16) {
197  uint8x16_t v1 = vld1q_u8(a + i);
198  uint8x16_t v2 = vld1q_u8(b + i);
199  uint8x16_t x = veorq_u8(v1, v2);
200  vst1q_u8(r + i, x);
201  }
202 #if defined(__IAR_SYSTEMS_ICC__)
203  /* This if statement helps some compilers (e.g., IAR) optimise out the byte-by-byte tail case
204  * where n is a constant multiple of 16.
205  * For other compilers (e.g. recent gcc and clang) it makes no difference if n is a compile-time
206  * constant, and is a very small perf regression if n is not a compile-time constant. */
207  if (n % 16 == 0) {
208  return;
209  }
210 #endif
211 #elif defined(MBEDTLS_ARCH_IS_X64) || defined(MBEDTLS_ARCH_IS_ARM64)
212  /* This codepath probably only makes sense on architectures with 64-bit registers */
213  for (; (i + 8) <= n; i += 8) {
216  }
217 #if defined(__IAR_SYSTEMS_ICC__)
218  if (n % 8 == 0) {
219  return;
220  }
221 #endif
222 #else
223  for (; (i + 4) <= n; i += 4) {
226  }
227 #if defined(__IAR_SYSTEMS_ICC__)
228  if (n % 4 == 0) {
229  return;
230  }
231 #endif
232 #endif
233 #endif
234  for (; i < n; i++) {
235  r[i] = a[i] ^ b[i];
236  }
237 }
238 
239 /* Always inline mbedtls_xor_no_simd() as we see significant perf regressions when it does not get
240  * inlined (e.g., observed about 3x perf difference in gcm_mult_largetable with gcc 7 - 12) */
241 #if defined(__IAR_SYSTEMS_ICC__)
242 #pragma inline = forced
243 #elif defined(__GNUC__)
244 __attribute__((always_inline))
245 #endif
246 /**
247  * Perform a fast block XOR operation, such that
248  * r[i] = a[i] ^ b[i] where 0 <= i < n
249  *
250  * In some situations, this can perform better than mbedtls_xor() (e.g., it's about 5%
251  * better in AES-CBC).
252  *
253  * \param r Pointer to result (buffer of at least \p n bytes). \p r
254  * may be equal to either \p a or \p b, but behaviour when
255  * it overlaps in other ways is undefined.
256  * \param a Pointer to input (buffer of at least \p n bytes)
257  * \param b Pointer to input (buffer of at least \p n bytes)
258  * \param n Number of bytes to process.
259  *
260  * \note Depending on the situation, it may be faster to use either mbedtls_xor() or
261  * mbedtls_xor_no_simd() (these are functionally equivalent).
262  * If the result is used immediately after the xor operation in non-SIMD code (e.g, in
263  * AES-CBC), there may be additional latency to transfer the data from SIMD to scalar
264  * registers, and in this case, mbedtls_xor_no_simd() may be faster. In other cases where
265  * the result is not used immediately (e.g., in AES-CTR), mbedtls_xor() may be faster.
266  * For targets without SIMD support, they will behave the same.
267  */
268 static inline void mbedtls_xor_no_simd(unsigned char *r,
269  const unsigned char *a,
270  const unsigned char *b,
271  size_t n)
272 {
273  size_t i = 0;
274 #if defined(MBEDTLS_EFFICIENT_UNALIGNED_ACCESS)
275 #if defined(MBEDTLS_ARCH_IS_X64) || defined(MBEDTLS_ARCH_IS_ARM64)
276  /* This codepath probably only makes sense on architectures with 64-bit registers */
277  for (; (i + 8) <= n; i += 8) {
280  }
281 #if defined(__IAR_SYSTEMS_ICC__)
282  /* This if statement helps some compilers (e.g., IAR) optimise out the byte-by-byte tail case
283  * where n is a constant multiple of 8.
284  * For other compilers (e.g. recent gcc and clang) it makes no difference if n is a compile-time
285  * constant, and is a very small perf regression if n is not a compile-time constant. */
286  if (n % 8 == 0) {
287  return;
288  }
289 #endif
290 #else
291  for (; (i + 4) <= n; i += 4) {
294  }
295 #if defined(__IAR_SYSTEMS_ICC__)
296  if (n % 4 == 0) {
297  return;
298  }
299 #endif
300 #endif
301 #endif
302  for (; i < n; i++) {
303  r[i] = a[i] ^ b[i];
304  }
305 }
306 
307 /* Fix MSVC C99 compatible issue
308  * MSVC support __func__ from visual studio 2015( 1900 )
309  * Use MSVC predefine macro to avoid name check fail.
310  */
311 #if (defined(_MSC_VER) && (_MSC_VER <= 1900))
312 #define /*no-check-names*/ __func__ __FUNCTION__
313 #endif
314 
315 /* Define `asm` for compilers which don't define it. */
316 /* *INDENT-OFF* */
317 #ifndef asm
318 #if defined(__IAR_SYSTEMS_ICC__)
319 #define asm __asm
320 #else
321 #define asm __asm__
322 #endif
323 #endif
324 /* *INDENT-ON* */
325 
326 /*
327  * Define the constraint used for read-only pointer operands to aarch64 asm.
328  *
329  * This is normally the usual "r", but for aarch64_32 (aka ILP32,
330  * as found in watchos), "p" is required to avoid warnings from clang.
331  *
332  * Note that clang does not recognise '+p' or '=p', and armclang
333  * does not recognise 'p' at all. Therefore, to update a pointer from
334  * aarch64 assembly, it is necessary to use something like:
335  *
336  * uintptr_t uptr = (uintptr_t) ptr;
337  * asm( "ldr x4, [%x0], #8" ... : "+r" (uptr) : : )
338  * ptr = (void*) uptr;
339  *
340  * Note that the "x" in "%x0" is neccessary; writing "%0" will cause warnings.
341  */
342 #if defined(__aarch64__) && defined(MBEDTLS_HAVE_ASM)
343 #if UINTPTR_MAX == 0xfffffffful
344 /* ILP32: Specify the pointer operand slightly differently, as per #7787. */
345 #define MBEDTLS_ASM_AARCH64_PTR_CONSTRAINT "p"
346 #elif UINTPTR_MAX == 0xfffffffffffffffful
347 /* Normal case (64-bit pointers): use "r" as the constraint for pointer operands to asm */
348 #define MBEDTLS_ASM_AARCH64_PTR_CONSTRAINT "r"
349 #else
350 #error "Unrecognised pointer size for aarch64"
351 #endif
352 #endif
353 
354 /* Always provide a static assert macro, so it can be used unconditionally.
355  * It will expand to nothing on some systems.
356  * Can be used outside functions (but don't add a trailing ';' in that case:
357  * the semicolon is included here to avoid triggering -Wextra-semi when
358  * MBEDTLS_STATIC_ASSERT() expands to nothing).
359  * Can't use the C11-style `defined(static_assert)` on FreeBSD, since it
360  * defines static_assert even with -std=c99, but then complains about it.
361  */
362 #if defined(static_assert) && !defined(__FreeBSD__)
363 #define MBEDTLS_STATIC_ASSERT(expr, msg) static_assert(expr, msg);
364 #else
365 #define MBEDTLS_STATIC_ASSERT(expr, msg)
366 #endif
367 
368 #if defined(__has_builtin)
369 #define MBEDTLS_HAS_BUILTIN(x) __has_builtin(x)
370 #else
371 #define MBEDTLS_HAS_BUILTIN(x) 0
372 #endif
373 
374 /* Define compiler branch hints */
375 #if MBEDTLS_HAS_BUILTIN(__builtin_expect)
376 #define MBEDTLS_LIKELY(x) __builtin_expect(!!(x), 1)
377 #define MBEDTLS_UNLIKELY(x) __builtin_expect(!!(x), 0)
378 #else
379 #define MBEDTLS_LIKELY(x) x
380 #define MBEDTLS_UNLIKELY(x) x
381 #endif
382 
383 /* MBEDTLS_ASSUME may be used to provide additional information to the compiler
384  * which can result in smaller code-size. */
385 #if MBEDTLS_HAS_BUILTIN(__builtin_assume)
386 /* clang provides __builtin_assume */
387 #define MBEDTLS_ASSUME(x) __builtin_assume(x)
388 #elif MBEDTLS_HAS_BUILTIN(__builtin_unreachable)
389 /* gcc and IAR can use __builtin_unreachable */
390 #define MBEDTLS_ASSUME(x) do { if (!(x)) __builtin_unreachable(); } while (0)
391 #elif defined(_MSC_VER)
392 /* Supported by MSVC since VS 2005 */
393 #define MBEDTLS_ASSUME(x) __assume(x)
394 #else
395 #define MBEDTLS_ASSUME(x) do { } while (0)
396 #endif
397 
398 /* For gcc -Os, override with -O2 for a given function.
399  *
400  * This will not affect behaviour for other optimisation settings, e.g. -O0.
401  */
402 #if defined(MBEDTLS_COMPILER_IS_GCC) && defined(__OPTIMIZE_SIZE__)
403 #define MBEDTLS_OPTIMIZE_FOR_PERFORMANCE __attribute__((optimize("-O2")))
404 #else
405 #define MBEDTLS_OPTIMIZE_FOR_PERFORMANCE
406 #endif
407 
408 /* Suppress compiler warnings for unused functions and variables. */
409 #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__has_attribute)
410 # if __has_attribute(unused)
411 # define MBEDTLS_MAYBE_UNUSED __attribute__((unused))
412 # endif
413 #endif
414 #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__GNUC__)
415 # define MBEDTLS_MAYBE_UNUSED __attribute__((unused))
416 #endif
417 #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__IAR_SYSTEMS_ICC__) && defined(__VER__)
418 /* IAR does support __attribute__((unused)), but only if the -e flag (extended language support)
419  * is given; the pragma always works.
420  * Unfortunately the pragma affects the rest of the file where it is used, but this is harmless.
421  * Check for version 5.2 or later - this pragma may be supported by earlier versions, but I wasn't
422  * able to find documentation).
423  */
424 # if (__VER__ >= 5020000)
425 # define MBEDTLS_MAYBE_UNUSED _Pragma("diag_suppress=Pe177")
426 # endif
427 #endif
428 #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(_MSC_VER)
429 # define MBEDTLS_MAYBE_UNUSED __pragma(warning(suppress:4189))
430 #endif
431 #if !defined(MBEDTLS_MAYBE_UNUSED)
432 # define MBEDTLS_MAYBE_UNUSED
433 #endif
434 
435 #endif /* MBEDTLS_LIBRARY_COMMON_H */
Utility code for dealing with unaligned memory accesses.
static void mbedtls_put_unaligned_uint32(void *p, uint32_t x)
Write the unsigned 32 bits integer to the given address, which need not be aligned.
Definition: alignment.h:194
static uint64_t mbedtls_get_unaligned_uint64(const void *p)
Read the unsigned 64 bits integer from the given address, which need not be aligned.
Definition: alignment.h:219
static uint32_t mbedtls_get_unaligned_uint32(const void *p)
Read the unsigned 32 bits integer from the given address, which need not be aligned.
Definition: alignment.h:167
static void mbedtls_put_unaligned_uint64(void *p, uint64_t x)
Write the unsigned 64 bits integer to the given address, which need not be aligned.
Definition: alignment.h:246
static unsigned char * mbedtls_buffer_offset(unsigned char *p, size_t n)
Return an offset into a buffer.
Definition: common.h:138
static void mbedtls_xor(unsigned char *r, const unsigned char *a, const unsigned char *b, size_t n)
Perform a fast block XOR operation, such that r[i] = a[i] ^ b[i] where 0 <= i < n.
Definition: common.h:186
void mbedtls_zeroize_and_free(void *buf, size_t len)
Securely zeroize a buffer then free it.
static const unsigned char * mbedtls_buffer_offset_const(const unsigned char *p, size_t n)
Return an offset into a read-only buffer.
Definition: common.h:155
static void mbedtls_xor_no_simd(unsigned char *r, const unsigned char *a, const unsigned char *b, size_t n)
Perform a fast block XOR operation, such that r[i] = a[i] ^ b[i] where 0 <= i < n.
Definition: common.h:268
#define test(a, b, c, d, e)
Definition: numeric.c:170
Uint8 uint64_t
Uint4 uint32_t
#define NULL
Definition: ncbistd.hpp:225
const CVect2< U > & v2
Definition: globals.hpp:440
FILE * file
char * buf
int i
yy_size_t n
int len
Build-time configuration info.
unsigned int a
Definition: ncbi_localip.c:102
double r(size_t dimension_, const Int4 *score_, const double *prob_, double theta_)
Modified on Tue Jun 25 13:32:08 2024 by modify_doxy.py rev. 669887