1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2  * All rights reserved.
3  *
4  * This package is an SSL implementation written
5  * by Eric Young (eay@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@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@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@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 #include <openssl/stack.h>
58 
59 #include <string.h>
60 
61 #include <openssl/mem.h>
62 
63 /* kMinSize is the number of pointers that will be initially allocated in a new
64  * stack. */
65 static const size_t kMinSize = 4;
66 
sk_new(stack_cmp_func comp)67 _STACK *sk_new(stack_cmp_func comp) {
68   _STACK *ret;
69 
70   ret = OPENSSL_malloc(sizeof(_STACK));
71   if (ret == NULL) {
72     goto err;
73   }
74   memset(ret, 0, sizeof(_STACK));
75 
76   ret->data = OPENSSL_malloc(sizeof(void *) * kMinSize);
77   if (ret->data == NULL) {
78     goto err;
79   }
80 
81   memset(ret->data, 0, sizeof(void *) * kMinSize);
82 
83   ret->comp = comp;
84   ret->num_alloc = kMinSize;
85 
86   return ret;
87 
88 err:
89   OPENSSL_free(ret);
90   return NULL;
91 }
92 
sk_new_null(void)93 _STACK *sk_new_null(void) { return sk_new(NULL); }
94 
sk_num(const _STACK * sk)95 size_t sk_num(const _STACK *sk) {
96   if (sk == NULL) {
97     return 0;
98   }
99   return sk->num;
100 }
101 
sk_zero(_STACK * sk)102 void sk_zero(_STACK *sk) {
103   if (sk == NULL || sk->num == 0) {
104     return;
105   }
106   memset(sk->data, 0, sizeof(void*) * sk->num);
107   sk->num = 0;
108   sk->sorted = 0;
109 }
110 
sk_value(const _STACK * sk,size_t i)111 void *sk_value(const _STACK *sk, size_t i) {
112   if (!sk || i >= sk->num) {
113     return NULL;
114   }
115   return sk->data[i];
116 }
117 
sk_set(_STACK * sk,size_t i,void * value)118 void *sk_set(_STACK *sk, size_t i, void *value) {
119   if (!sk || i >= sk->num) {
120     return NULL;
121   }
122   return sk->data[i] = value;
123 }
124 
sk_free(_STACK * sk)125 void sk_free(_STACK *sk) {
126   if (sk == NULL) {
127     return;
128   }
129   OPENSSL_free(sk->data);
130   OPENSSL_free(sk);
131 }
132 
sk_pop_free(_STACK * sk,void (* func)(void *))133 void sk_pop_free(_STACK *sk, void (*func)(void *)) {
134   size_t i;
135 
136   if (sk == NULL) {
137     return;
138   }
139 
140   for (i = 0; i < sk->num; i++) {
141     if (sk->data[i] != NULL) {
142       func(sk->data[i]);
143     }
144   }
145   sk_free(sk);
146 }
147 
sk_insert(_STACK * sk,void * p,size_t where)148 size_t sk_insert(_STACK *sk, void *p, size_t where) {
149   if (sk == NULL) {
150     return 0;
151   }
152 
153   if (sk->num_alloc <= sk->num + 1) {
154     /* Attempt to double the size of the array. */
155     size_t new_alloc = sk->num_alloc << 1;
156     size_t alloc_size = new_alloc * sizeof(void *);
157     void **data;
158 
159     /* If the doubling overflowed, try to increment. */
160     if (new_alloc < sk->num_alloc || alloc_size / sizeof(void *) != new_alloc) {
161       new_alloc = sk->num_alloc + 1;
162       alloc_size = new_alloc * sizeof(void *);
163     }
164 
165     /* If the increment also overflowed, fail. */
166     if (new_alloc < sk->num_alloc || alloc_size / sizeof(void *) != new_alloc) {
167       return 0;
168     }
169 
170     data = OPENSSL_realloc(sk->data, alloc_size);
171     if (data == NULL) {
172       return 0;
173     }
174 
175     sk->data = data;
176     sk->num_alloc = new_alloc;
177   }
178 
179   if (where >= sk->num) {
180     sk->data[sk->num] = p;
181   } else {
182     memmove(&sk->data[where + 1], &sk->data[where],
183             sizeof(void *) * (sk->num - where));
184     sk->data[where] = p;
185   }
186 
187   sk->num++;
188   sk->sorted = 0;
189 
190   return sk->num;
191 }
192 
sk_delete(_STACK * sk,size_t where)193 void *sk_delete(_STACK *sk, size_t where) {
194   void *ret;
195 
196   if (!sk || where >= sk->num) {
197     return NULL;
198   }
199 
200   ret = sk->data[where];
201 
202   if (where != sk->num - 1) {
203     memmove(&sk->data[where], &sk->data[where + 1],
204             sizeof(void *) * (sk->num - where - 1));
205   }
206 
207   sk->num--;
208   return ret;
209 }
210 
sk_delete_ptr(_STACK * sk,void * p)211 void *sk_delete_ptr(_STACK *sk, void *p) {
212   size_t i;
213 
214   if (sk == NULL) {
215     return NULL;
216   }
217 
218   for (i = 0; i < sk->num; i++) {
219     if (sk->data[i] == p) {
220       return sk_delete(sk, i);
221     }
222   }
223 
224   return NULL;
225 }
226 
sk_find(_STACK * sk,size_t * out_index,void * p)227 int sk_find(_STACK *sk, size_t *out_index, void *p) {
228   const void *const *r;
229   size_t i;
230   int (*comp_func)(const void *,const void *);
231 
232   if (sk == NULL) {
233     return 0;
234   }
235 
236   if (sk->comp == NULL) {
237     /* Use pointer equality when no comparison function has been set. */
238     for (i = 0; i < sk->num; i++) {
239       if (sk->data[i] == p) {
240         if (out_index) {
241           *out_index = i;
242         }
243         return 1;
244       }
245     }
246     return 0;
247   }
248 
249   if (p == NULL) {
250     return 0;
251   }
252 
253   sk_sort(sk);
254 
255   /* sk->comp is a function that takes pointers to pointers to elements, but
256    * qsort and bsearch take a comparison function that just takes pointers to
257    * elements. However, since we're passing an array of pointers to
258    * qsort/bsearch, we can just cast the comparison function and everything
259    * works. */
260   comp_func=(int (*)(const void *,const void *))(sk->comp);
261   r = bsearch(&p, sk->data, sk->num, sizeof(void *), comp_func);
262   if (r == NULL) {
263     return 0;
264   }
265   i = ((void **)r) - sk->data;
266   /* This function always returns the first result. */
267   while (i > 0 && sk->comp((const void**) &p, (const void**) &sk->data[i-1]) == 0) {
268     i--;
269   }
270   if (out_index) {
271     *out_index = i;
272   }
273   return 1;
274 }
275 
sk_shift(_STACK * sk)276 void *sk_shift(_STACK *sk) {
277   if (sk == NULL) {
278     return NULL;
279   }
280   if (sk->num == 0) {
281     return NULL;
282   }
283   return sk_delete(sk, 0);
284 }
285 
sk_push(_STACK * sk,void * p)286 size_t sk_push(_STACK *sk, void *p) { return (sk_insert(sk, p, sk->num)); }
287 
sk_pop(_STACK * sk)288 void *sk_pop(_STACK *sk) {
289   if (sk == NULL) {
290     return NULL;
291   }
292   if (sk->num == 0) {
293     return NULL;
294   }
295   return sk_delete(sk, sk->num - 1);
296 }
297 
sk_dup(const _STACK * sk)298 _STACK *sk_dup(const _STACK *sk) {
299   _STACK *ret;
300   void **s;
301 
302   if (sk == NULL) {
303     return NULL;
304   }
305 
306   ret = sk_new(sk->comp);
307   if (ret == NULL) {
308     goto err;
309   }
310 
311   s = (void **)OPENSSL_realloc(ret->data, sizeof(void *) * sk->num_alloc);
312   if (s == NULL) {
313     goto err;
314   }
315   ret->data = s;
316 
317   ret->num = sk->num;
318   memcpy(ret->data, sk->data, sizeof(void *) * sk->num);
319   ret->sorted = sk->sorted;
320   ret->num_alloc = sk->num_alloc;
321   ret->comp = sk->comp;
322   return ret;
323 
324 err:
325   sk_free(ret);
326   return NULL;
327 }
328 
sk_sort(_STACK * sk)329 void sk_sort(_STACK *sk) {
330   int (*comp_func)(const void *,const void *);
331 
332   if (sk == NULL || sk->sorted) {
333     return;
334   }
335 
336   /* See the comment in sk_find about this cast. */
337   comp_func = (int (*)(const void *, const void *))(sk->comp);
338   qsort(sk->data, sk->num, sizeof(void *), comp_func);
339   sk->sorted = 1;
340 }
341 
sk_is_sorted(const _STACK * sk)342 int sk_is_sorted(const _STACK *sk) {
343   if (!sk) {
344     return 1;
345   }
346   return sk->sorted;
347 }
348 
sk_set_cmp_func(_STACK * sk,stack_cmp_func comp)349 stack_cmp_func sk_set_cmp_func(_STACK *sk, stack_cmp_func comp) {
350   stack_cmp_func old = sk->comp;
351 
352   if (sk->comp != comp) {
353     sk->sorted = 0;
354   }
355   sk->comp = comp;
356 
357   return old;
358 }
359 
sk_deep_copy(const _STACK * sk,void * (* copy_func)(void *),void (* free_func)(void *))360 _STACK *sk_deep_copy(const _STACK *sk, void *(*copy_func)(void *),
361                      void (*free_func)(void *)) {
362   _STACK *ret = sk_dup(sk);
363   if (ret == NULL) {
364     return NULL;
365   }
366 
367   size_t i;
368   for (i = 0; i < ret->num; i++) {
369     if (ret->data[i] == NULL) {
370       continue;
371     }
372     ret->data[i] = copy_func(ret->data[i]);
373     if (ret->data[i] == NULL) {
374       size_t j;
375       for (j = 0; j < i; j++) {
376         if (ret->data[j] != NULL) {
377           free_func(ret->data[j]);
378         }
379       }
380       sk_free(ret);
381       return NULL;
382     }
383   }
384 
385   return ret;
386 }
387