• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 #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_cmp_func is a comparison function that returns a value < 0, 0 or > 0
90  * if |*a| is less than, equal to or greater than |*b|, respectively.  Note the
91  * extra indirection - the function is given a pointer to a pointer to the
92  * element. This differs from the usual qsort/bsearch comparison function. */
93 typedef int (*stack_cmp_func)(const void **a, const void **b);
94 
95 /* stack_st contains an array of pointers. It is not designed to be used
96  * directly, rather the wrapper macros should be used. */
97 typedef struct stack_st {
98   /* num contains the number of valid pointers in |data|. */
99   size_t num;
100   void **data;
101   /* sorted is non-zero if the values pointed to by |data| are in ascending
102    * order, based on |comp|. */
103   int sorted;
104   /* num_alloc contains the number of pointers allocated in the buffer pointed
105    * to by |data|, which may be larger than |num|. */
106   size_t num_alloc;
107   /* comp is an optional comparison function. */
108   stack_cmp_func comp;
109 } _STACK;
110 
111 
112 #define STACK_OF(type) struct stack_st_##type
113 
114 #define DECLARE_STACK_OF(type) STACK_OF(type);
115 
116 /* These are the raw stack functions, you shouldn't be using them. Rather you
117  * should be using the type stack macros implemented above. */
118 
119 /* sk_new creates a new, empty stack with the given comparison function, which
120  * may be zero. It returns the new stack or NULL on allocation failure. */
121 OPENSSL_EXPORT _STACK *sk_new(stack_cmp_func comp);
122 
123 /* sk_new_null creates a new, empty stack. It returns the new stack or NULL on
124  * allocation failure. */
125 OPENSSL_EXPORT _STACK *sk_new_null(void);
126 
127 /* sk_num returns the number of elements in |s|. */
128 OPENSSL_EXPORT size_t sk_num(const _STACK *sk);
129 
130 /* sk_zero resets |sk| to the empty state but does nothing to free the
131  * individual elements themselves. */
132 OPENSSL_EXPORT void sk_zero(_STACK *sk);
133 
134 /* sk_value returns the |i|th pointer in |sk|, or NULL if |i| is out of
135  * range. */
136 OPENSSL_EXPORT void *sk_value(const _STACK *sk, size_t i);
137 
138 /* sk_set sets the |i|th pointer in |sk| to |p| and returns |p|. If |i| is out
139  * of range, it returns NULL. */
140 OPENSSL_EXPORT void *sk_set(_STACK *sk, size_t i, void *p);
141 
142 /* sk_free frees the given stack and array of pointers, but does nothing to
143  * free the individual elements. Also see |sk_pop_free|. */
144 OPENSSL_EXPORT void sk_free(_STACK *sk);
145 
146 /* sk_pop_free calls |free_func| on each element in the stack and then frees
147  * the stack itself. */
148 OPENSSL_EXPORT void sk_pop_free(_STACK *sk, void (*free_func)(void *));
149 
150 /* sk_insert inserts |p| into the stack at index |where|, moving existing
151  * elements if needed. It returns the length of the new stack, or zero on
152  * error. */
153 OPENSSL_EXPORT size_t sk_insert(_STACK *sk, void *p, size_t where);
154 
155 /* sk_delete removes the pointer at index |where|, moving other elements down
156  * if needed. It returns the removed pointer, or NULL if |where| is out of
157  * range. */
158 OPENSSL_EXPORT void *sk_delete(_STACK *sk, size_t where);
159 
160 /* sk_delete_ptr removes, at most, one instance of |p| from the stack based on
161  * pointer equality. If an instance of |p| is found then |p| is returned,
162  * otherwise it returns NULL. */
163 OPENSSL_EXPORT void *sk_delete_ptr(_STACK *sk, void *p);
164 
165 /* sk_find returns the first value in the stack equal to |p|. If a comparison
166  * function has been set on the stack, then equality is defined by it and the
167  * stack will be sorted if need be so that a binary search can be used.
168  * Otherwise pointer equality is used. If a matching element is found, its
169  * index is written to |*out_index| (if |out_index| is not NULL) and one is
170  * returned. Otherwise zero is returned. */
171 OPENSSL_EXPORT int sk_find(_STACK *sk, size_t *out_index, void *p);
172 
173 /* sk_shift removes and returns the first element in the stack, or returns NULL
174  * if the stack is empty. */
175 OPENSSL_EXPORT void *sk_shift(_STACK *sk);
176 
177 /* sk_push appends |p| to the stack and returns the length of the new stack, or
178  * 0 on allocation failure. */
179 OPENSSL_EXPORT size_t sk_push(_STACK *sk, void *p);
180 
181 /* sk_pop returns and removes the last element on the stack, or NULL if the
182  * stack is empty. */
183 OPENSSL_EXPORT void *sk_pop(_STACK *sk);
184 
185 /* sk_dup performs a shallow copy of a stack and returns the new stack, or NULL
186  * on error. */
187 OPENSSL_EXPORT _STACK *sk_dup(const _STACK *sk);
188 
189 /* sk_sort sorts the elements of |sk| into ascending order based on the
190  * comparison function. The stack maintains a |sorted| flag and sorting an
191  * already sorted stack is a no-op. */
192 OPENSSL_EXPORT void sk_sort(_STACK *sk);
193 
194 /* sk_is_sorted returns one if |sk| is known to be sorted and zero
195  * otherwise. */
196 OPENSSL_EXPORT int sk_is_sorted(const _STACK *sk);
197 
198 /* sk_set_cmp_func sets the comparison function to be used by |sk| and returns
199  * the previous one. */
200 OPENSSL_EXPORT stack_cmp_func sk_set_cmp_func(_STACK *sk, stack_cmp_func comp);
201 
202 /* sk_deep_copy performs a copy of |sk| and of each of the non-NULL elements in
203  * |sk| by using |copy_func|. If an error occurs, |free_func| is used to free
204  * any copies already made and NULL is returned. */
205 OPENSSL_EXPORT _STACK *sk_deep_copy(const _STACK *sk,
206                                     void *(*copy_func)(void *),
207                                     void (*free_func)(void *));
208 
209 
210 /* Defining stack types.
211  *
212  * This set of macros is used to emit the typed functions that act on a
213  * |STACK_OF(T)|. */
214 
215 /* Stack functions must be tagged unused to support file-local stack types.
216  * Clang's -Wunused-function only allows unused static inline functions if they
217  * are defined in a header. */
218 
219 #define DEFINE_STACK_OF_IMPL(name, ptrtype, constptrtype)                      \
220   DECLARE_STACK_OF(name);                                                      \
221                                                                                \
222   typedef int (*stack_##name##_cmp_func)(constptrtype *a, constptrtype *b);    \
223                                                                                \
224   static inline OPENSSL_UNUSED STACK_OF(name) *                                \
225       sk_##name##_new(stack_##name##_cmp_func comp) {                          \
226     return (STACK_OF(name) *)sk_new((stack_cmp_func)comp);                     \
227   }                                                                            \
228                                                                                \
229   static inline OPENSSL_UNUSED STACK_OF(name) *sk_##name##_new_null(void) {    \
230     return (STACK_OF(name) *)sk_new_null();                                    \
231   }                                                                            \
232                                                                                \
233   static inline OPENSSL_UNUSED size_t sk_##name##_num(                         \
234       const STACK_OF(name) *sk) {                                              \
235     return sk_num((const _STACK *)sk);                                         \
236   }                                                                            \
237                                                                                \
238   static inline OPENSSL_UNUSED void sk_##name##_zero(STACK_OF(name) *sk) {     \
239     sk_zero((_STACK *)sk);                                                     \
240   }                                                                            \
241                                                                                \
242   static inline OPENSSL_UNUSED ptrtype sk_##name##_value(                      \
243       const STACK_OF(name) *sk, size_t i) {                                    \
244     return (ptrtype)sk_value((const _STACK *)sk, i);                           \
245   }                                                                            \
246                                                                                \
247   static inline OPENSSL_UNUSED ptrtype sk_##name##_set(STACK_OF(name) *sk,     \
248                                                        size_t i, ptrtype p) {  \
249     return (ptrtype)sk_set((_STACK *)sk, i, (void *)p);                        \
250   }                                                                            \
251                                                                                \
252   static inline OPENSSL_UNUSED void sk_##name##_free(STACK_OF(name) *sk) {     \
253     sk_free((_STACK *)sk);                                                     \
254   }                                                                            \
255                                                                                \
256   static inline OPENSSL_UNUSED void sk_##name##_pop_free(                      \
257       STACK_OF(name) *sk, void (*free_func)(ptrtype p)) {                      \
258     sk_pop_free((_STACK *)sk, (void (*)(void *))free_func);                    \
259   }                                                                            \
260                                                                                \
261   static inline OPENSSL_UNUSED size_t sk_##name##_insert(                      \
262       STACK_OF(name) *sk, ptrtype p, size_t where) {                           \
263     return sk_insert((_STACK *)sk, (void *)p, where);                          \
264   }                                                                            \
265                                                                                \
266   static inline OPENSSL_UNUSED ptrtype sk_##name##_delete(STACK_OF(name) *sk,  \
267                                                           size_t where) {      \
268     return (ptrtype)sk_delete((_STACK *)sk, where);                            \
269   }                                                                            \
270                                                                                \
271   static inline OPENSSL_UNUSED ptrtype sk_##name##_delete_ptr(                 \
272       STACK_OF(name) *sk, ptrtype p) {                                         \
273     return (ptrtype)sk_delete_ptr((_STACK *)sk, (void *)p);                    \
274   }                                                                            \
275                                                                                \
276   static inline OPENSSL_UNUSED int sk_##name##_find(                           \
277       STACK_OF(name) *sk, size_t *out_index, ptrtype p) {                      \
278     return sk_find((_STACK *)sk, out_index, (void *)p);                        \
279   }                                                                            \
280                                                                                \
281   static inline OPENSSL_UNUSED ptrtype sk_##name##_shift(STACK_OF(name) *sk) { \
282     return (ptrtype)sk_shift((_STACK *)sk);                                    \
283   }                                                                            \
284                                                                                \
285   static inline OPENSSL_UNUSED size_t sk_##name##_push(STACK_OF(name) *sk,     \
286                                                        ptrtype p) {            \
287     return sk_push((_STACK *)sk, (void *)p);                                   \
288   }                                                                            \
289                                                                                \
290   static inline OPENSSL_UNUSED ptrtype sk_##name##_pop(STACK_OF(name) *sk) {   \
291     return (ptrtype)sk_pop((_STACK *)sk);                                      \
292   }                                                                            \
293                                                                                \
294   static inline OPENSSL_UNUSED STACK_OF(name) *                                \
295       sk_##name##_dup(const STACK_OF(name) *sk) {                              \
296     return (STACK_OF(name) *)sk_dup((const _STACK *)sk);                       \
297   }                                                                            \
298                                                                                \
299   static inline OPENSSL_UNUSED void sk_##name##_sort(STACK_OF(name) *sk) {     \
300     sk_sort((_STACK *)sk);                                                     \
301   }                                                                            \
302                                                                                \
303   static inline OPENSSL_UNUSED int sk_##name##_is_sorted(                      \
304       const STACK_OF(name) *sk) {                                              \
305     return sk_is_sorted((const _STACK *)sk);                                   \
306   }                                                                            \
307                                                                                \
308   static inline OPENSSL_UNUSED stack_##name##_cmp_func                         \
309       sk_##name##_set_cmp_func(STACK_OF(name) *sk,                             \
310                                stack_##name##_cmp_func comp) {                 \
311     return (stack_##name##_cmp_func)sk_set_cmp_func((_STACK *)sk,              \
312                                                     (stack_cmp_func)comp);     \
313   }                                                                            \
314                                                                                \
315   static inline OPENSSL_UNUSED STACK_OF(name) *                                \
316       sk_##name##_deep_copy(const STACK_OF(name) *sk,                          \
317                             ptrtype(*copy_func)(ptrtype),                      \
318                             void (*free_func)(ptrtype)) {                      \
319     return (STACK_OF(name) *)sk_deep_copy((_STACK *)sk,                        \
320                                           (void *(*)(void *))copy_func,        \
321                                           (void (*)(void *))free_func);        \
322   }
323 
324 /* DEFINE_STACK_OF defines |STACK_OF(type)| to be a stack whose elements are
325  * |type| *. */
326 #define DEFINE_STACK_OF(type) DEFINE_STACK_OF_IMPL(type, type *, const type *)
327 
328 /* DEFINE_CONST_STACK_OF defines |STACK_OF(type)| to be a stack whose elements
329  * are const |type| *. */
330 #define DEFINE_CONST_STACK_OF(type) \
331   DEFINE_STACK_OF_IMPL(type, const type *, const type *)
332 
333 /* DEFINE_SPECIAL_STACK_OF defines |STACK_OF(type)| to be a stack whose elements
334  * are |type|, where |type| must be a typedef for a pointer. */
335 #define DEFINE_SPECIAL_STACK_OF(type)                          \
336   OPENSSL_COMPILE_ASSERT(sizeof(type) == sizeof(void *),       \
337                          special_stack_of_non_pointer_##type); \
338   DEFINE_STACK_OF_IMPL(type, type, const type)
339 
340 
341 typedef char *OPENSSL_STRING;
342 
343 DEFINE_STACK_OF(void)
344 DEFINE_SPECIAL_STACK_OF(OPENSSL_STRING)
345 
346 
347 #if defined(__cplusplus)
348 }  /* extern C */
349 #endif
350 
351 #endif  /* OPENSSL_HEADER_STACK_H */
352