xref: /freebsd/crypto/openssl/crypto/mem.c (revision ad991e4c142ebabad7aef488ad97b189ecabb270)
1 /*
2  * Copyright 1995-2023 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (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
8  */
9 
10 #include "e_os.h"
11 #include "internal/cryptlib.h"
12 #include "crypto/cryptlib.h"
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <limits.h>
16 #include <openssl/crypto.h>
17 
18 /*
19  * the following pointers may be changed as long as 'allow_customize' is set
20  */
21 static int allow_customize = 1;
22 static CRYPTO_malloc_fn malloc_impl = CRYPTO_malloc;
23 static CRYPTO_realloc_fn realloc_impl = CRYPTO_realloc;
24 static CRYPTO_free_fn free_impl = CRYPTO_free;
25 
26 #if !defined(OPENSSL_NO_CRYPTO_MDEBUG) && !defined(FIPS_MODULE)
27 # include "internal/tsan_assist.h"
28 
29 # ifdef TSAN_REQUIRES_LOCKING
30 #  define INCREMENT(x) /* empty */
31 #  define LOAD(x) 0
32 # else  /* TSAN_REQUIRES_LOCKING */
33 static TSAN_QUALIFIER int malloc_count;
34 static TSAN_QUALIFIER int realloc_count;
35 static TSAN_QUALIFIER int free_count;
36 
37 #  define INCREMENT(x) tsan_counter(&(x))
38 #  define LOAD(x)      tsan_load(&x)
39 # endif /* TSAN_REQUIRES_LOCKING */
40 
41 static char *md_failstring;
42 static long md_count;
43 static int md_fail_percent = 0;
44 static int md_tracefd = -1;
45 
46 static void parseit(void);
47 static int shouldfail(void);
48 
49 # define FAILTEST() if (shouldfail()) return NULL
50 
51 #else
52 
53 # define INCREMENT(x) /* empty */
54 # define FAILTEST() /* empty */
55 #endif
56 
CRYPTO_set_mem_functions(CRYPTO_malloc_fn malloc_fn,CRYPTO_realloc_fn realloc_fn,CRYPTO_free_fn free_fn)57 int CRYPTO_set_mem_functions(CRYPTO_malloc_fn malloc_fn,
58                              CRYPTO_realloc_fn realloc_fn,
59                              CRYPTO_free_fn free_fn)
60 {
61     if (!allow_customize)
62         return 0;
63     if (malloc_fn != NULL)
64         malloc_impl = malloc_fn;
65     if (realloc_fn != NULL)
66         realloc_impl = realloc_fn;
67     if (free_fn != NULL)
68         free_impl = free_fn;
69     return 1;
70 }
71 
CRYPTO_get_mem_functions(CRYPTO_malloc_fn * malloc_fn,CRYPTO_realloc_fn * realloc_fn,CRYPTO_free_fn * free_fn)72 void CRYPTO_get_mem_functions(CRYPTO_malloc_fn *malloc_fn,
73                               CRYPTO_realloc_fn *realloc_fn,
74                               CRYPTO_free_fn *free_fn)
75 {
76     if (malloc_fn != NULL)
77         *malloc_fn = malloc_impl;
78     if (realloc_fn != NULL)
79         *realloc_fn = realloc_impl;
80     if (free_fn != NULL)
81         *free_fn = free_impl;
82 }
83 
84 #if !defined(OPENSSL_NO_CRYPTO_MDEBUG) && !defined(FIPS_MODULE)
CRYPTO_get_alloc_counts(int * mcount,int * rcount,int * fcount)85 void CRYPTO_get_alloc_counts(int *mcount, int *rcount, int *fcount)
86 {
87     if (mcount != NULL)
88         *mcount = LOAD(malloc_count);
89     if (rcount != NULL)
90         *rcount = LOAD(realloc_count);
91     if (fcount != NULL)
92         *fcount = LOAD(free_count);
93 }
94 
95 /*
96  * Parse a "malloc failure spec" string.  This likes like a set of fields
97  * separated by semicolons.  Each field has a count and an optional failure
98  * percentage.  For example:
99  *          100@0;100@25;0@0
100  *    or    100;100@25;0
101  * This means 100 mallocs succeed, then next 100 fail 25% of the time, and
102  * all remaining (count is zero) succeed.
103  * The failure percentge can have 2 digits after the comma.  For example:
104  *          0@0.01
105  * This means 0.01% of all allocations will fail.
106  */
parseit(void)107 static void parseit(void)
108 {
109     char *semi = strchr(md_failstring, ';');
110     char *atsign;
111 
112     if (semi != NULL)
113         *semi++ = '\0';
114 
115     /* Get the count (atol will stop at the @ if there), and percentage */
116     md_count = atol(md_failstring);
117     atsign = strchr(md_failstring, '@');
118     md_fail_percent = atsign == NULL ? 0 : (int)(atof(atsign + 1) * 100 + 0.5);
119 
120     if (semi != NULL)
121         md_failstring = semi;
122 }
123 
124 /*
125  * Windows doesn't have random() and srandom(), but it has rand() and srand().
126  * Some rand() implementations aren't good, but we're not
127  * dealing with secure randomness here.
128  */
129 # ifdef _WIN32
130 #  define random() rand()
131 #  define srandom(seed) srand(seed)
132 # endif
133 /*
134  * See if the current malloc should fail.
135  */
shouldfail(void)136 static int shouldfail(void)
137 {
138     int roll = (int)(random() % 10000);
139     int shoulditfail = roll < md_fail_percent;
140 # ifndef _WIN32
141 /* suppressed on Windows as POSIX-like file descriptors are non-inheritable */
142     int len;
143     char buff[80];
144 
145     if (md_tracefd > 0) {
146         BIO_snprintf(buff, sizeof(buff),
147                      "%c C%ld %%%d R%d\n",
148                      shoulditfail ? '-' : '+', md_count, md_fail_percent, roll);
149         len = strlen(buff);
150         if (write(md_tracefd, buff, len) != len)
151             perror("shouldfail write failed");
152     }
153 # endif
154 
155     if (md_count) {
156         /* If we used up this one, go to the next. */
157         if (--md_count == 0)
158             parseit();
159     }
160 
161     return shoulditfail;
162 }
163 
ossl_malloc_setup_failures(void)164 void ossl_malloc_setup_failures(void)
165 {
166     const char *cp = getenv("OPENSSL_MALLOC_FAILURES");
167 
168     if (cp != NULL && (md_failstring = strdup(cp)) != NULL)
169         parseit();
170     if ((cp = getenv("OPENSSL_MALLOC_FD")) != NULL)
171         md_tracefd = atoi(cp);
172     if ((cp = getenv("OPENSSL_MALLOC_SEED")) != NULL)
173         srandom(atoi(cp));
174 }
175 #endif
176 
CRYPTO_malloc(size_t num,const char * file,int line)177 void *CRYPTO_malloc(size_t num, const char *file, int line)
178 {
179     INCREMENT(malloc_count);
180     if (malloc_impl != CRYPTO_malloc)
181         return malloc_impl(num, file, line);
182 
183     if (num == 0)
184         return NULL;
185 
186     FAILTEST();
187     if (allow_customize) {
188         /*
189          * Disallow customization after the first allocation. We only set this
190          * if necessary to avoid a store to the same cache line on every
191          * allocation.
192          */
193         allow_customize = 0;
194     }
195 
196     return malloc(num);
197 }
198 
CRYPTO_zalloc(size_t num,const char * file,int line)199 void *CRYPTO_zalloc(size_t num, const char *file, int line)
200 {
201     void *ret;
202 
203     ret = CRYPTO_malloc(num, file, line);
204     if (ret != NULL)
205         memset(ret, 0, num);
206 
207     return ret;
208 }
209 
CRYPTO_realloc(void * str,size_t num,const char * file,int line)210 void *CRYPTO_realloc(void *str, size_t num, const char *file, int line)
211 {
212     INCREMENT(realloc_count);
213     if (realloc_impl != CRYPTO_realloc)
214         return realloc_impl(str, num, file, line);
215 
216     if (str == NULL)
217         return CRYPTO_malloc(num, file, line);
218 
219     if (num == 0) {
220         CRYPTO_free(str, file, line);
221         return NULL;
222     }
223 
224     FAILTEST();
225     return realloc(str, num);
226 }
227 
CRYPTO_clear_realloc(void * str,size_t old_len,size_t num,const char * file,int line)228 void *CRYPTO_clear_realloc(void *str, size_t old_len, size_t num,
229                            const char *file, int line)
230 {
231     void *ret = NULL;
232 
233     if (str == NULL)
234         return CRYPTO_malloc(num, file, line);
235 
236     if (num == 0) {
237         CRYPTO_clear_free(str, old_len, file, line);
238         return NULL;
239     }
240 
241     /* Can't shrink the buffer since memcpy below copies |old_len| bytes. */
242     if (num < old_len) {
243         OPENSSL_cleanse((char*)str + num, old_len - num);
244         return str;
245     }
246 
247     ret = CRYPTO_malloc(num, file, line);
248     if (ret != NULL) {
249         memcpy(ret, str, old_len);
250         CRYPTO_clear_free(str, old_len, file, line);
251     }
252     return ret;
253 }
254 
CRYPTO_free(void * str,const char * file,int line)255 void CRYPTO_free(void *str, const char *file, int line)
256 {
257     INCREMENT(free_count);
258     if (free_impl != CRYPTO_free) {
259         free_impl(str, file, line);
260         return;
261     }
262 
263     free(str);
264 }
265 
CRYPTO_clear_free(void * str,size_t num,const char * file,int line)266 void CRYPTO_clear_free(void *str, size_t num, const char *file, int line)
267 {
268     if (str == NULL)
269         return;
270     if (num)
271         OPENSSL_cleanse(str, num);
272     CRYPTO_free(str, file, line);
273 }
274 
275 #if !defined(OPENSSL_NO_CRYPTO_MDEBUG)
276 
277 # ifndef OPENSSL_NO_DEPRECATED_3_0
CRYPTO_mem_ctrl(int mode)278 int CRYPTO_mem_ctrl(int mode)
279 {
280     (void)mode;
281     return -1;
282 }
283 
CRYPTO_set_mem_debug(int flag)284 int CRYPTO_set_mem_debug(int flag)
285 {
286     (void)flag;
287     return -1;
288 }
289 
CRYPTO_mem_debug_push(const char * info,const char * file,int line)290 int CRYPTO_mem_debug_push(const char *info, const char *file, int line)
291 {
292     (void)info; (void)file; (void)line;
293     return 0;
294 }
295 
CRYPTO_mem_debug_pop(void)296 int CRYPTO_mem_debug_pop(void)
297 {
298     return 0;
299 }
300 
CRYPTO_mem_debug_malloc(void * addr,size_t num,int flag,const char * file,int line)301 void CRYPTO_mem_debug_malloc(void *addr, size_t num, int flag,
302                              const char *file, int line)
303 {
304     (void)addr; (void)num; (void)flag; (void)file; (void)line;
305 }
306 
CRYPTO_mem_debug_realloc(void * addr1,void * addr2,size_t num,int flag,const char * file,int line)307 void CRYPTO_mem_debug_realloc(void *addr1, void *addr2, size_t num, int flag,
308                               const char *file, int line)
309 {
310     (void)addr1; (void)addr2; (void)num; (void)flag; (void)file; (void)line;
311 }
312 
CRYPTO_mem_debug_free(void * addr,int flag,const char * file,int line)313 void CRYPTO_mem_debug_free(void *addr, int flag,
314                            const char *file, int line)
315 {
316     (void)addr; (void)flag; (void)file; (void)line;
317 }
318 
CRYPTO_mem_leaks(BIO * b)319 int CRYPTO_mem_leaks(BIO *b)
320 {
321     (void)b;
322     return -1;
323 }
324 
325 #  ifndef OPENSSL_NO_STDIO
CRYPTO_mem_leaks_fp(FILE * fp)326 int CRYPTO_mem_leaks_fp(FILE *fp)
327 {
328     (void)fp;
329     return -1;
330 }
331 #  endif
332 
CRYPTO_mem_leaks_cb(int (* cb)(const char * str,size_t len,void * u),void * u)333 int CRYPTO_mem_leaks_cb(int (*cb)(const char *str, size_t len, void *u),
334                         void *u)
335 {
336     (void)cb; (void)u;
337     return -1;
338 }
339 
340 # endif
341 
342 #endif
343