2 * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
11 #include "internal/cryptlib.h"
12 #include "internal/numbers.h"
13 #include <openssl/stack.h>
14 #include <openssl/objects.h>
16 #include <openssl/e_os2.h> /* For ossl_inline */
19 * The initial number of nodes in the array.
21 static const int min_nodes = 4;
22 static const int max_nodes = SIZE_MAX / sizeof(void *) < INT_MAX
23 ? (int)(SIZE_MAX / sizeof(void *))
31 OPENSSL_sk_compfunc comp;
34 OPENSSL_sk_compfunc OPENSSL_sk_set_cmp_func(OPENSSL_STACK *sk, OPENSSL_sk_compfunc c)
36 OPENSSL_sk_compfunc old = sk->comp;
45 OPENSSL_STACK *OPENSSL_sk_dup(const OPENSSL_STACK *sk)
49 if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL) {
50 CRYPTOerr(CRYPTO_F_OPENSSL_SK_DUP, ERR_R_MALLOC_FAILURE);
54 /* direct structure assignment */
58 /* postpone |ret->data| allocation */
63 /* duplicate |sk->data| content */
64 if ((ret->data = OPENSSL_malloc(sizeof(*ret->data) * sk->num_alloc)) == NULL)
66 memcpy(ret->data, sk->data, sizeof(void *) * sk->num);
73 OPENSSL_STACK *OPENSSL_sk_deep_copy(const OPENSSL_STACK *sk,
74 OPENSSL_sk_copyfunc copy_func,
75 OPENSSL_sk_freefunc free_func)
80 if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL) {
81 CRYPTOerr(CRYPTO_F_OPENSSL_SK_DEEP_COPY, ERR_R_MALLOC_FAILURE);
85 /* direct structure assignment */
89 /* postpone |ret| data allocation */
95 ret->num_alloc = sk->num > min_nodes ? sk->num : min_nodes;
96 ret->data = OPENSSL_zalloc(sizeof(*ret->data) * ret->num_alloc);
97 if (ret->data == NULL) {
102 for (i = 0; i < ret->num; ++i) {
103 if (sk->data[i] == NULL)
105 if ((ret->data[i] = copy_func(sk->data[i])) == NULL) {
107 if (ret->data[i] != NULL)
108 free_func((void *)ret->data[i]);
109 OPENSSL_sk_free(ret);
116 OPENSSL_STACK *OPENSSL_sk_new_null(void)
118 return OPENSSL_sk_new_reserve(NULL, 0);
121 OPENSSL_STACK *OPENSSL_sk_new(OPENSSL_sk_compfunc c)
123 return OPENSSL_sk_new_reserve(c, 0);
127 * Calculate the array growth based on the target size.
129 * The growth fraction is a rational number and is defined by a numerator
130 * and a denominator. According to Andrew Koenig in his paper "Why Are
131 * Vectors Efficient?" from JOOP 11(5) 1998, this factor should be less
132 * than the golden ratio (1.618...).
134 * We use 3/2 = 1.5 for simplicity of calculation and overflow checking.
135 * Another option 8/5 = 1.6 allows for slightly faster growth, although safe
136 * computation is more difficult.
138 * The limit to avoid overflow is spot on. The modulo three correction term
139 * ensures that the limit is the largest number than can be expanded by the
140 * growth factor without exceeding the hard limit.
142 * Do not call it with |current| lower than 2, or it will infinitely loop.
144 static ossl_inline int compute_growth(int target, int current)
146 const int limit = (max_nodes / 3) * 2 + (max_nodes % 3 ? 1 : 0);
148 while (current < target) {
149 /* Check to see if we're at the hard limit */
150 if (current >= max_nodes)
153 /* Expand the size by a factor of 3/2 if it is within range */
154 current = current < limit ? current + current / 2 : max_nodes;
159 /* internal STACK storage allocation */
160 static int sk_reserve(OPENSSL_STACK *st, int n, int exact)
162 const void **tmpdata;
165 /* Check to see the reservation isn't exceeding the hard limit */
166 if (n > max_nodes - st->num)
169 /* Figure out the new size */
170 num_alloc = st->num + n;
171 if (num_alloc < min_nodes)
172 num_alloc = min_nodes;
174 /* If |st->data| allocation was postponed */
175 if (st->data == NULL) {
177 * At this point, |st->num_alloc| and |st->num| are 0;
178 * so |num_alloc| value is |n| or |min_nodes| if greater than |n|.
180 if ((st->data = OPENSSL_zalloc(sizeof(void *) * num_alloc)) == NULL) {
181 CRYPTOerr(CRYPTO_F_SK_RESERVE, ERR_R_MALLOC_FAILURE);
184 st->num_alloc = num_alloc;
189 if (num_alloc <= st->num_alloc)
191 num_alloc = compute_growth(num_alloc, st->num_alloc);
194 } else if (num_alloc == st->num_alloc) {
198 tmpdata = OPENSSL_realloc((void *)st->data, sizeof(void *) * num_alloc);
203 st->num_alloc = num_alloc;
207 OPENSSL_STACK *OPENSSL_sk_new_reserve(OPENSSL_sk_compfunc c, int n)
209 OPENSSL_STACK *st = OPENSSL_zalloc(sizeof(OPENSSL_STACK));
219 if (!sk_reserve(st, n, 1)) {
227 int OPENSSL_sk_reserve(OPENSSL_STACK *st, int n)
231 return sk_reserve(st, n, 1);
234 int OPENSSL_sk_insert(OPENSSL_STACK *st, const void *data, int loc)
236 if (st->num == max_nodes)
239 if (!sk_reserve(st, 1, 0))
242 if ((loc >= st->num) || (loc < 0)) {
243 st->data[st->num] = data;
245 memmove(&st->data[loc + 1], &st->data[loc],
246 sizeof(st->data[0]) * (st->num - loc));
247 st->data[loc] = data;
254 static ossl_inline void *internal_delete(OPENSSL_STACK *st, int loc)
256 const void *ret = st->data[loc];
258 if (loc != st->num - 1)
259 memmove(&st->data[loc], &st->data[loc + 1],
260 sizeof(st->data[0]) * (st->num - loc - 1));
266 void *OPENSSL_sk_delete_ptr(OPENSSL_STACK *st, const void *p)
270 for (i = 0; i < st->num; i++)
271 if (st->data[i] == p)
272 return internal_delete(st, i);
276 void *OPENSSL_sk_delete(OPENSSL_STACK *st, int loc)
278 if (loc < 0 || loc >= st->num)
281 return internal_delete(st, loc);
284 static int internal_find(OPENSSL_STACK *st, const void *data,
293 if (st->comp == NULL) {
294 for (i = 0; i < st->num; i++)
295 if (st->data[i] == data)
302 qsort(st->data, st->num, sizeof(void *), st->comp);
303 st->sorted = 1; /* empty or single-element stack is considered sorted */
307 r = OBJ_bsearch_ex_(&data, st->data, st->num, sizeof(void *), st->comp,
310 return r == NULL ? -1 : (int)((const void **)r - st->data);
313 int OPENSSL_sk_find(OPENSSL_STACK *st, const void *data)
315 return internal_find(st, data, OBJ_BSEARCH_FIRST_VALUE_ON_MATCH);
318 int OPENSSL_sk_find_ex(OPENSSL_STACK *st, const void *data)
320 return internal_find(st, data, OBJ_BSEARCH_VALUE_ON_NOMATCH);
323 int OPENSSL_sk_push(OPENSSL_STACK *st, const void *data)
325 return OPENSSL_sk_insert(st, data, st->num);
328 int OPENSSL_sk_unshift(OPENSSL_STACK *st, const void *data)
330 return OPENSSL_sk_insert(st, data, 0);
333 void *OPENSSL_sk_shift(OPENSSL_STACK *st)
335 if (st == NULL || st->num == 0)
337 return internal_delete(st, 0);
340 void *OPENSSL_sk_pop(OPENSSL_STACK *st)
342 if (st == NULL || st->num == 0)
344 return internal_delete(st, st->num - 1);
347 void OPENSSL_sk_zero(OPENSSL_STACK *st)
351 memset(st->data, 0, sizeof(*st->data) * st->num);
355 void OPENSSL_sk_pop_free(OPENSSL_STACK *st, OPENSSL_sk_freefunc func)
361 for (i = 0; i < st->num; i++)
362 if (st->data[i] != NULL)
363 func((char *)st->data[i]);
367 void OPENSSL_sk_free(OPENSSL_STACK *st)
371 OPENSSL_free(st->data);
375 int OPENSSL_sk_num(const OPENSSL_STACK *st)
377 return st == NULL ? -1 : st->num;
380 void *OPENSSL_sk_value(const OPENSSL_STACK *st, int i)
382 if (i < 0 || i >= st->num)
384 return (void *)st->data[i];
387 void *OPENSSL_sk_set(OPENSSL_STACK *st, int i, const void *data)
389 if (i < 0 || i >= st->num)
393 return (void *)st->data[i];
396 void OPENSSL_sk_sort(OPENSSL_STACK *st)
398 if (!st->sorted && st->comp != NULL) {
400 qsort(st->data, st->num, sizeof(void *), st->comp);
401 st->sorted = 1; /* empty or single-element stack is considered sorted */
405 int OPENSSL_sk_is_sorted(const OPENSSL_STACK *st)