1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay (at) cryptsoft.com). 6 * The implementation was written so as to conform with Netscapes SSL. 7 * 8 * This library is free for commercial and non-commercial use as long as 9 * the following conditions are aheared to. The following conditions 10 * apply to all code found in this distribution, be it the RC4, RSA, 11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 12 * included with this distribution is covered by the same copyright terms 13 * except that the holder is Tim Hudson (tjh (at) cryptsoft.com). 14 * 15 * Copyright remains Eric Young's, and as such any Copyright notices in 16 * the code are not to be removed. 17 * If this package is used in a product, Eric Young should be given attribution 18 * as the author of the parts of the library used. 19 * This can be in the form of a textual message at program startup or 20 * in documentation (online or textual) provided with the package. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. All advertising materials mentioning features or use of this software 31 * must display the following acknowledgement: 32 * "This product includes cryptographic software written by 33 * Eric Young (eay (at) cryptsoft.com)" 34 * The word 'cryptographic' can be left out if the rouines from the library 35 * being used are not cryptographic related :-). 36 * 4. If you include any Windows specific code (or a derivative thereof) from 37 * the apps directory (application code) you must include an acknowledgement: 38 * "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * The licence and distribution terms for any publically available version or 53 * derivative of this code cannot be changed. i.e. this code cannot simply be 54 * copied and put under another distribution licence 55 * [including the GNU Public Licence.] */ 56 57 #ifndef OPENSSL_HEADER_STACK_H 58 #define OPENSSL_HEADER_STACK_H 59 60 #include <openssl/base.h> 61 62 #include <openssl/type_check.h> 63 64 #if defined(__cplusplus) 65 extern "C" { 66 #endif 67 68 69 // A stack, in OpenSSL, is an array of pointers. They are the most commonly 70 // used collection object. 71 // 72 // This file defines macros for type safe use of the stack functions. A stack 73 // of a specific type of object has type |STACK_OF(type)|. This can be defined 74 // (once) with |DEFINE_STACK_OF(type)| and declared where needed with 75 // |DECLARE_STACK_OF(type)|. For example: 76 // 77 // typedef struct foo_st { 78 // int bar; 79 // } FOO; 80 // 81 // DEFINE_STACK_OF(FOO) 82 // 83 // Although note that the stack will contain /pointers/ to |FOO|. 84 // 85 // A macro will be defined for each of the sk_* functions below. For 86 // STACK_OF(FOO), the macros would be sk_FOO_new, sk_FOO_pop etc. 87 88 89 // stack_free_func is a function that frees an element in a stack. Note its 90 // actual type is void (*)(T *) for some T. Low-level |sk_*| functions will be 91 // passed a type-specific wrapper to call it correctly. 92 typedef void (*stack_free_func)(void *ptr); 93 94 // stack_copy_func is a function that copies an element in a stack. Note its 95 // actual type is T *(*)(T *) for some T. Low-level |sk_*| functions will be 96 // passed a type-specific wrapper to call it correctly. 97 typedef void *(*stack_copy_func)(void *ptr); 98 99 // stack_cmp_func is a comparison function that returns a value < 0, 0 or > 0 100 // if |*a| is less than, equal to or greater than |*b|, respectively. Note the 101 // extra indirection - the function is given a pointer to a pointer to the 102 // element. This differs from the usual qsort/bsearch comparison function. 103 // 104 // Note its actual type is int (*)(const T **, const T **). Low-level |sk_*| 105 // functions will be passed a type-specific wrapper to call it correctly. 106 typedef int (*stack_cmp_func)(const void **a, const void **b); 107 108 // stack_st contains an array of pointers. It is not designed to be used 109 // directly, rather the wrapper macros should be used. 110 typedef struct stack_st { 111 // num contains the number of valid pointers in |data|. 112 size_t num; 113 void **data; 114 // sorted is non-zero if the values pointed to by |data| are in ascending 115 // order, based on |comp|. 116 int sorted; 117 // num_alloc contains the number of pointers allocated in the buffer pointed 118 // to by |data|, which may be larger than |num|. 119 size_t num_alloc; 120 // comp is an optional comparison function. 121 stack_cmp_func comp; 122 } _STACK; 123 124 125 #define STACK_OF(type) struct stack_st_##type 126 127 #define DECLARE_STACK_OF(type) STACK_OF(type); 128 129 // These are the raw stack functions, you shouldn't be using them. Rather you 130 // should be using the type stack macros implemented above. 131 132 // sk_new creates a new, empty stack with the given comparison function, which 133 // may be zero. It returns the new stack or NULL on allocation failure. 134 OPENSSL_EXPORT _STACK *sk_new(stack_cmp_func comp); 135 136 // sk_new_null creates a new, empty stack. It returns the new stack or NULL on 137 // allocation failure. 138 OPENSSL_EXPORT _STACK *sk_new_null(void); 139 140 // sk_num returns the number of elements in |s|. 141 OPENSSL_EXPORT size_t sk_num(const _STACK *sk); 142 143 // sk_zero resets |sk| to the empty state but does nothing to free the 144 // individual elements themselves. 145 OPENSSL_EXPORT void sk_zero(_STACK *sk); 146 147 // sk_value returns the |i|th pointer in |sk|, or NULL if |i| is out of 148 // range. 149 OPENSSL_EXPORT void *sk_value(const _STACK *sk, size_t i); 150 151 // sk_set sets the |i|th pointer in |sk| to |p| and returns |p|. If |i| is out 152 // of range, it returns NULL. 153 OPENSSL_EXPORT void *sk_set(_STACK *sk, size_t i, void *p); 154 155 // sk_free frees the given stack and array of pointers, but does nothing to 156 // free the individual elements. Also see |sk_pop_free_ex|. 157 OPENSSL_EXPORT void sk_free(_STACK *sk); 158 159 // sk_pop_free_ex calls |free_func| on each element in the stack and then frees 160 // the stack itself. Note this corresponds to |sk_FOO_pop_free|. It is named 161 // |sk_pop_free_ex| as a workaround for existing code calling an older version 162 // of |sk_pop_free|. 163 OPENSSL_EXPORT void sk_pop_free_ex(_STACK *sk, 164 void (*call_free_func)(stack_free_func, 165 void *), 166 stack_free_func free_func); 167 168 // sk_insert inserts |p| into the stack at index |where|, moving existing 169 // elements if needed. It returns the length of the new stack, or zero on 170 // error. 171 OPENSSL_EXPORT size_t sk_insert(_STACK *sk, void *p, size_t where); 172 173 // sk_delete removes the pointer at index |where|, moving other elements down 174 // if needed. It returns the removed pointer, or NULL if |where| is out of 175 // range. 176 OPENSSL_EXPORT void *sk_delete(_STACK *sk, size_t where); 177 178 // sk_delete_ptr removes, at most, one instance of |p| from the stack based on 179 // pointer equality. If an instance of |p| is found then |p| is returned, 180 // otherwise it returns NULL. 181 OPENSSL_EXPORT void *sk_delete_ptr(_STACK *sk, const void *p); 182 183 // sk_find returns the first value in the stack equal to |p|. If a comparison 184 // function has been set on the stack, equality is defined by it, otherwise 185 // pointer equality is used. If the stack is sorted, then a binary search is 186 // used, otherwise a linear search is performed. If a matching element is found, 187 // its index is written to 188 // |*out_index| (if |out_index| is not NULL) and one is returned. Otherwise zero 189 // is returned. 190 // 191 // Note this differs from OpenSSL. The type signature is slightly different, and 192 // OpenSSL's sk_find will implicitly sort |sk| if it has a comparison function 193 // defined. 194 OPENSSL_EXPORT int sk_find(const _STACK *sk, size_t *out_index, const void *p, 195 int (*call_cmp_func)(stack_cmp_func, const void **, 196 const void **)); 197 198 // sk_shift removes and returns the first element in the stack, or returns NULL 199 // if the stack is empty. 200 OPENSSL_EXPORT void *sk_shift(_STACK *sk); 201 202 // sk_push appends |p| to the stack and returns the length of the new stack, or 203 // 0 on allocation failure. 204 OPENSSL_EXPORT size_t sk_push(_STACK *sk, void *p); 205 206 // sk_pop returns and removes the last element on the stack, or NULL if the 207 // stack is empty. 208 OPENSSL_EXPORT void *sk_pop(_STACK *sk); 209 210 // sk_dup performs a shallow copy of a stack and returns the new stack, or NULL 211 // on error. 212 OPENSSL_EXPORT _STACK *sk_dup(const _STACK *sk); 213 214 // sk_sort sorts the elements of |sk| into ascending order based on the 215 // comparison function. The stack maintains a |sorted| flag and sorting an 216 // already sorted stack is a no-op. 217 OPENSSL_EXPORT void sk_sort(_STACK *sk); 218 219 // sk_is_sorted returns one if |sk| is known to be sorted and zero 220 // otherwise. 221 OPENSSL_EXPORT int sk_is_sorted(const _STACK *sk); 222 223 // sk_set_cmp_func sets the comparison function to be used by |sk| and returns 224 // the previous one. 225 OPENSSL_EXPORT stack_cmp_func sk_set_cmp_func(_STACK *sk, stack_cmp_func comp); 226 227 // sk_deep_copy performs a copy of |sk| and of each of the non-NULL elements in 228 // |sk| by using |copy_func|. If an error occurs, |free_func| is used to free 229 // any copies already made and NULL is returned. 230 OPENSSL_EXPORT _STACK *sk_deep_copy( 231 const _STACK *sk, void *(*call_copy_func)(stack_copy_func, void *), 232 stack_copy_func copy_func, void (*call_free_func)(stack_free_func, void *), 233 stack_free_func free_func); 234 235 236 // Deprecated functions. 237 238 // sk_pop_free behaves like |sk_pop_free_ex| but performs an invalid function 239 // pointer cast. It exists because some existing callers called |sk_pop_free| 240 // directly. 241 // 242 // TODO(davidben): Migrate callers to bssl::UniquePtr and remove this. 243 OPENSSL_EXPORT void sk_pop_free(_STACK *sk, stack_free_func free_func); 244 245 246 // Defining stack types. 247 // 248 // This set of macros is used to emit the typed functions that act on a 249 // |STACK_OF(T)|. 250 251 #if !defined(BORINGSSL_NO_CXX) 252 extern "C++" { 253 BSSL_NAMESPACE_BEGIN 254 namespace internal { 255 template <typename T> 256 struct StackTraits {}; 257 } 258 BSSL_NAMESPACE_END 259 } 260 261 #define BORINGSSL_DEFINE_STACK_TRAITS(name, type, is_const) \ 262 extern "C++" { \ 263 BSSL_NAMESPACE_BEGIN \ 264 namespace internal { \ 265 template <> \ 266 struct StackTraits<STACK_OF(name)> { \ 267 static constexpr bool kIsStack = true; \ 268 using Type = type; \ 269 static constexpr bool kIsConst = is_const; \ 270 }; \ 271 } \ 272 BSSL_NAMESPACE_END \ 273 } 274 275 #else 276 #define BORINGSSL_DEFINE_STACK_TRAITS(name, type, is_const) 277 #endif 278 279 #define BORINGSSL_DEFINE_STACK_OF_IMPL(name, ptrtype, constptrtype) \ 280 DECLARE_STACK_OF(name) \ 281 \ 282 typedef void (*stack_##name##_free_func)(ptrtype); \ 283 typedef ptrtype (*stack_##name##_copy_func)(ptrtype); \ 284 typedef int (*stack_##name##_cmp_func)(constptrtype *a, constptrtype *b); \ 285 \ 286 OPENSSL_INLINE void sk_##name##_call_free_func(stack_free_func free_func, \ 287 void *ptr) { \ 288 ((stack_##name##_free_func)free_func)((ptrtype)ptr); \ 289 } \ 290 \ 291 OPENSSL_INLINE void *sk_##name##_call_copy_func(stack_copy_func copy_func, \ 292 void *ptr) { \ 293 return (void *)((stack_##name##_copy_func)copy_func)((ptrtype)ptr); \ 294 } \ 295 \ 296 OPENSSL_INLINE int sk_##name##_call_cmp_func( \ 297 stack_cmp_func cmp_func, const void **a, const void **b) { \ 298 constptrtype a_ptr = (constptrtype)*a; \ 299 constptrtype b_ptr = (constptrtype)*b; \ 300 return ((stack_##name##_cmp_func)cmp_func)(&a_ptr, &b_ptr); \ 301 } \ 302 \ 303 OPENSSL_INLINE STACK_OF(name) * \ 304 sk_##name##_new(stack_##name##_cmp_func comp) { \ 305 return (STACK_OF(name) *)sk_new((stack_cmp_func)comp); \ 306 } \ 307 \ 308 OPENSSL_INLINE STACK_OF(name) *sk_##name##_new_null(void) { \ 309 return (STACK_OF(name) *)sk_new_null(); \ 310 } \ 311 \ 312 OPENSSL_INLINE size_t sk_##name##_num(const STACK_OF(name) *sk) { \ 313 return sk_num((const _STACK *)sk); \ 314 } \ 315 \ 316 OPENSSL_INLINE void sk_##name##_zero(STACK_OF(name) *sk) { \ 317 sk_zero((_STACK *)sk); \ 318 } \ 319 \ 320 OPENSSL_INLINE ptrtype sk_##name##_value(const STACK_OF(name) *sk, \ 321 size_t i) { \ 322 return (ptrtype)sk_value((const _STACK *)sk, i); \ 323 } \ 324 \ 325 OPENSSL_INLINE ptrtype sk_##name##_set(STACK_OF(name) *sk, size_t i, \ 326 ptrtype p) { \ 327 return (ptrtype)sk_set((_STACK *)sk, i, (void *)p); \ 328 } \ 329 \ 330 OPENSSL_INLINE void sk_##name##_free(STACK_OF(name) * sk) { \ 331 sk_free((_STACK *)sk); \ 332 } \ 333 \ 334 OPENSSL_INLINE void sk_##name##_pop_free( \ 335 STACK_OF(name) * sk, stack_##name##_free_func free_func) { \ 336 sk_pop_free_ex((_STACK *)sk, sk_##name##_call_free_func, \ 337 (stack_free_func)free_func); \ 338 } \ 339 \ 340 OPENSSL_INLINE size_t sk_##name##_insert(STACK_OF(name) *sk, ptrtype p, \ 341 size_t where) { \ 342 return sk_insert((_STACK *)sk, (void *)p, where); \ 343 } \ 344 \ 345 OPENSSL_INLINE ptrtype sk_##name##_delete(STACK_OF(name) *sk, \ 346 size_t where) { \ 347 return (ptrtype)sk_delete((_STACK *)sk, where); \ 348 } \ 349 \ 350 OPENSSL_INLINE ptrtype sk_##name##_delete_ptr(STACK_OF(name) *sk, \ 351 constptrtype p) { \ 352 return (ptrtype)sk_delete_ptr((_STACK *)sk, (const void *)p); \ 353 } \ 354 \ 355 OPENSSL_INLINE int sk_##name##_find(const STACK_OF(name) *sk, \ 356 size_t * out_index, constptrtype p) { \ 357 return sk_find((const _STACK *)sk, out_index, (const void *)p, \ 358 sk_##name##_call_cmp_func); \ 359 } \ 360 \ 361 OPENSSL_INLINE ptrtype sk_##name##_shift(STACK_OF(name) *sk) { \ 362 return (ptrtype)sk_shift((_STACK *)sk); \ 363 } \ 364 \ 365 OPENSSL_INLINE size_t sk_##name##_push(STACK_OF(name) *sk, ptrtype p) { \ 366 return sk_push((_STACK *)sk, (void *)p); \ 367 } \ 368 \ 369 OPENSSL_INLINE ptrtype sk_##name##_pop(STACK_OF(name) *sk) { \ 370 return (ptrtype)sk_pop((_STACK *)sk); \ 371 } \ 372 \ 373 OPENSSL_INLINE STACK_OF(name) * sk_##name##_dup(const STACK_OF(name) *sk) { \ 374 return (STACK_OF(name) *)sk_dup((const _STACK *)sk); \ 375 } \ 376 \ 377 OPENSSL_INLINE void sk_##name##_sort(STACK_OF(name) *sk) { \ 378 sk_sort((_STACK *)sk); \ 379 } \ 380 \ 381 OPENSSL_INLINE int sk_##name##_is_sorted(const STACK_OF(name) *sk) { \ 382 return sk_is_sorted((const _STACK *)sk); \ 383 } \ 384 \ 385 OPENSSL_INLINE stack_##name##_cmp_func sk_##name##_set_cmp_func( \ 386 STACK_OF(name) *sk, stack_##name##_cmp_func comp) { \ 387 return (stack_##name##_cmp_func)sk_set_cmp_func((_STACK *)sk, \ 388 (stack_cmp_func)comp); \ 389 } \ 390 \ 391 OPENSSL_INLINE STACK_OF(name) * \ 392 sk_##name##_deep_copy(const STACK_OF(name) *sk, \ 393 ptrtype(*copy_func)(ptrtype), \ 394 void (*free_func)(ptrtype)) { \ 395 return (STACK_OF(name) *)sk_deep_copy( \ 396 (const _STACK *)sk, sk_##name##_call_copy_func, \ 397 (stack_copy_func)copy_func, sk_##name##_call_free_func, \ 398 (stack_free_func)free_func); \ 399 } 400 401 // DEFINE_NAMED_STACK_OF defines |STACK_OF(name)| to be a stack whose elements 402 // are |type| *. 403 #define DEFINE_NAMED_STACK_OF(name, type) \ 404 BORINGSSL_DEFINE_STACK_OF_IMPL(name, type *, const type *) \ 405 BORINGSSL_DEFINE_STACK_TRAITS(name, type, false) 406 407 // DEFINE_STACK_OF defines |STACK_OF(type)| to be a stack whose elements are 408 // |type| *. 409 #define DEFINE_STACK_OF(type) DEFINE_NAMED_STACK_OF(type, type) 410 411 // DEFINE_CONST_STACK_OF defines |STACK_OF(type)| to be a stack whose elements 412 // are const |type| *. 413 #define DEFINE_CONST_STACK_OF(type) \ 414 BORINGSSL_DEFINE_STACK_OF_IMPL(type, const type *, const type *) \ 415 BORINGSSL_DEFINE_STACK_TRAITS(type, const type, true) 416 417 // DEFINE_SPECIAL_STACK_OF defines |STACK_OF(type)| to be a stack whose elements 418 // are |type|, where |type| must be a typedef for a pointer. 419 #define DEFINE_SPECIAL_STACK_OF(type) \ 420 OPENSSL_STATIC_ASSERT(sizeof(type) == sizeof(void *), \ 421 #type " is not a pointer"); \ 422 BORINGSSL_DEFINE_STACK_OF_IMPL(type, type, const type) 423 424 425 typedef char *OPENSSL_STRING; 426 427 DEFINE_STACK_OF(void) 428 DEFINE_SPECIAL_STACK_OF(OPENSSL_STRING) 429 430 431 #if defined(__cplusplus) 432 } // extern C 433 #endif 434 435 #if !defined(BORINGSSL_NO_CXX) 436 extern "C++" { 437 438 #include <type_traits> 439 440 BSSL_NAMESPACE_BEGIN 441 442 namespace internal { 443 444 // Stacks defined with |DEFINE_CONST_STACK_OF| are freed with |sk_free|. 445 template <typename Stack> 446 struct DeleterImpl< 447 Stack, typename std::enable_if<StackTraits<Stack>::kIsConst>::type> { 448 static void Free(Stack *sk) { sk_free(reinterpret_cast<_STACK *>(sk)); } 449 }; 450 451 // Stacks defined with |DEFINE_STACK_OF| are freed with |sk_pop_free| and the 452 // corresponding type's deleter. 453 template <typename Stack> 454 struct DeleterImpl< 455 Stack, typename std::enable_if<!StackTraits<Stack>::kIsConst>::type> { 456 static void Free(Stack *sk) { 457 // sk_FOO_pop_free is defined by macros and bound by name, so we cannot 458 // access it from C++ here. 459 using Type = typename StackTraits<Stack>::Type; 460 sk_pop_free_ex(reinterpret_cast<_STACK *>(sk), 461 [](stack_free_func /* unused */, void *ptr) { 462 DeleterImpl<Type>::Free(reinterpret_cast<Type *>(ptr)); 463 }, 464 nullptr); 465 } 466 }; 467 468 template <typename Stack> 469 class StackIteratorImpl { 470 public: 471 using Type = typename StackTraits<Stack>::Type; 472 // Iterators must be default-constructable. 473 StackIteratorImpl() : sk_(nullptr), idx_(0) {} 474 StackIteratorImpl(const Stack *sk, size_t idx) : sk_(sk), idx_(idx) {} 475 476 bool operator==(StackIteratorImpl other) const { 477 return sk_ == other.sk_ && idx_ == other.idx_; 478 } 479 bool operator!=(StackIteratorImpl other) const { 480 return !(*this == other); 481 } 482 483 Type *operator*() const { 484 return reinterpret_cast<Type *>( 485 sk_value(reinterpret_cast<const _STACK *>(sk_), idx_)); 486 } 487 488 StackIteratorImpl &operator++(/* prefix */) { 489 idx_++; 490 return *this; 491 } 492 493 StackIteratorImpl operator++(int /* postfix */) { 494 StackIteratorImpl copy(*this); 495 ++(*this); 496 return copy; 497 } 498 499 private: 500 const Stack *sk_; 501 size_t idx_; 502 }; 503 504 template <typename Stack> 505 using StackIterator = typename std::enable_if<StackTraits<Stack>::kIsStack, 506 StackIteratorImpl<Stack>>::type; 507 508 } // namespace internal 509 510 // PushToStack pushes |elem| to |sk|. It returns true on success and false on 511 // allocation failure. 512 template <typename Stack> 513 inline 514 typename std::enable_if<!internal::StackTraits<Stack>::kIsConst, bool>::type 515 PushToStack(Stack *sk, 516 UniquePtr<typename internal::StackTraits<Stack>::Type> elem) { 517 if (!sk_push(reinterpret_cast<_STACK *>(sk), elem.get())) { 518 return false; 519 } 520 // sk_push takes ownership on success. 521 elem.release(); 522 return true; 523 } 524 525 BSSL_NAMESPACE_END 526 527 // Define begin() and end() for stack types so C++ range for loops work. 528 template <typename Stack> 529 inline bssl::internal::StackIterator<Stack> begin(const Stack *sk) { 530 return bssl::internal::StackIterator<Stack>(sk, 0); 531 } 532 533 template <typename Stack> 534 inline bssl::internal::StackIterator<Stack> end(const Stack *sk) { 535 return bssl::internal::StackIterator<Stack>( 536 sk, sk_num(reinterpret_cast<const _STACK *>(sk))); 537 } 538 539 } // extern C++ 540 #endif 541 542 #endif // OPENSSL_HEADER_STACK_H 543
