digest.c revision 296465 
1/* crypto/evp/digest.c */
2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to.  The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 *    notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 *    notice, this list of conditions and the following disclaimer in the
30 *    documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 *    must display the following acknowledgement:
33 *    "This product includes cryptographic software written by
34 *     Eric Young (eay@cryptsoft.com)"
35 *    The word 'cryptographic' can be left out if the rouines from the library
36 *    being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 *    the apps directory (application code) you must include an acknowledgement:
39 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed.  i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58/* ====================================================================
59 * Copyright (c) 1998-2001 The OpenSSL Project.  All rights reserved.
60 *
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
63 * are met:
64 *
65 * 1. Redistributions of source code must retain the above copyright
66 *    notice, this list of conditions and the following disclaimer.
67 *
68 * 2. Redistributions in binary form must reproduce the above copyright
69 *    notice, this list of conditions and the following disclaimer in
70 *    the documentation and/or other materials provided with the
71 *    distribution.
72 *
73 * 3. All advertising materials mentioning features or use of this
74 *    software must display the following acknowledgment:
75 *    "This product includes software developed by the OpenSSL Project
76 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77 *
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 *    endorse or promote products derived from this software without
80 *    prior written permission. For written permission, please contact
81 *    openssl-core@openssl.org.
82 *
83 * 5. Products derived from this software may not be called "OpenSSL"
84 *    nor may "OpenSSL" appear in their names without prior written
85 *    permission of the OpenSSL Project.
86 *
87 * 6. Redistributions of any form whatsoever must retain the following
88 *    acknowledgment:
89 *    "This product includes software developed by the OpenSSL Project
90 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 *
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
105 *
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com).  This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
109 *
110 */
111
112#include <stdio.h>
113#include "cryptlib.h"
114#include <openssl/objects.h>
115#include <openssl/evp.h>
116#ifndef OPENSSL_NO_ENGINE
117# include <openssl/engine.h>
118#endif
119#include "evp_locl.h"
120
121void EVP_MD_CTX_init(EVP_MD_CTX *ctx)
122{
123    memset(ctx, '\0', sizeof *ctx);
124}
125
126EVP_MD_CTX *EVP_MD_CTX_create(void)
127{
128    EVP_MD_CTX *ctx = OPENSSL_malloc(sizeof *ctx);
129
130    if (ctx)
131        EVP_MD_CTX_init(ctx);
132
133    return ctx;
134}
135
136int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type)
137{
138    EVP_MD_CTX_init(ctx);
139    return EVP_DigestInit_ex(ctx, type, NULL);
140}
141
142#ifdef OPENSSL_FIPS
143
144/*
145 * The purpose of these is to trap programs that attempt to use non FIPS
146 * algorithms in FIPS mode and ignore the errors.
147 */
148
149static int bad_init(EVP_MD_CTX *ctx)
150{
151    FIPS_ERROR_IGNORED("Digest init");
152    return 0;
153}
154
155static int bad_update(EVP_MD_CTX *ctx, const void *data, size_t count)
156{
157    FIPS_ERROR_IGNORED("Digest update");
158    return 0;
159}
160
161static int bad_final(EVP_MD_CTX *ctx, unsigned char *md)
162{
163    FIPS_ERROR_IGNORED("Digest Final");
164    return 0;
165}
166
167static const EVP_MD bad_md = {
168    0,
169    0,
170    0,
171    0,
172    bad_init,
173    bad_update,
174    bad_final,
175    NULL,
176    NULL,
177    NULL,
178    0,
179    {0, 0, 0, 0},
180};
181
182#endif
183
184#ifndef OPENSSL_NO_ENGINE
185
186# ifdef OPENSSL_FIPS
187
188static int do_engine_null(ENGINE *impl)
189{
190    return 0;
191}
192
193static int do_evp_md_engine_null(EVP_MD_CTX *ctx,
194                                 const EVP_MD **ptype, ENGINE *impl)
195{
196    return 1;
197}
198
199static int (*do_engine_init) (ENGINE *impl)
200    = do_engine_null;
201
202static int (*do_engine_finish) (ENGINE *impl)
203    = do_engine_null;
204
205static int (*do_evp_md_engine)
206 (EVP_MD_CTX *ctx, const EVP_MD **ptype, ENGINE *impl)
207    = do_evp_md_engine_null;
208
209void int_EVP_MD_set_engine_callbacks(int (*eng_md_init) (ENGINE *impl),
210                                     int (*eng_md_fin) (ENGINE *impl),
211                                     int (*eng_md_evp)
212                                      (EVP_MD_CTX *ctx, const EVP_MD **ptype,
213                                       ENGINE *impl))
214{
215    do_engine_init = eng_md_init;
216    do_engine_finish = eng_md_fin;
217    do_evp_md_engine = eng_md_evp;
218}
219
220# else
221
222#  define do_engine_init  ENGINE_init
223#  define do_engine_finish ENGINE_finish
224
225static int do_evp_md_engine(EVP_MD_CTX *ctx, const EVP_MD **ptype,
226                            ENGINE *impl)
227{
228    if (*ptype) {
229        /*
230         * Ensure an ENGINE left lying around from last time is cleared (the
231         * previous check attempted to avoid this if the same ENGINE and
232         * EVP_MD could be used).
233         */
234        if (ctx->engine)
235            ENGINE_finish(ctx->engine);
236        if (impl) {
237            if (!ENGINE_init(impl)) {
238                EVPerr(EVP_F_DO_EVP_MD_ENGINE, EVP_R_INITIALIZATION_ERROR);
239                return 0;
240            }
241        } else
242            /* Ask if an ENGINE is reserved for this job */
243            impl = ENGINE_get_digest_engine((*ptype)->type);
244        if (impl) {
245            /* There's an ENGINE for this job ... (apparently) */
246            const EVP_MD *d = ENGINE_get_digest(impl, (*ptype)->type);
247            if (!d) {
248                /* Same comment from evp_enc.c */
249                EVPerr(EVP_F_DO_EVP_MD_ENGINE, EVP_R_INITIALIZATION_ERROR);
250                ENGINE_finish(impl);
251                return 0;
252            }
253            /* We'll use the ENGINE's private digest definition */
254            *ptype = d;
255            /*
256             * Store the ENGINE functional reference so we know 'type' came
257             * from an ENGINE and we need to release it when done.
258             */
259            ctx->engine = impl;
260        } else
261            ctx->engine = NULL;
262    } else if (!ctx->digest) {
263        EVPerr(EVP_F_DO_EVP_MD_ENGINE, EVP_R_NO_DIGEST_SET);
264        return 0;
265    }
266    return 1;
267}
268
269# endif
270
271#endif
272
273int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl)
274{
275    M_EVP_MD_CTX_clear_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
276#ifdef OPENSSL_FIPS
277    if (FIPS_selftest_failed()) {
278        FIPSerr(FIPS_F_EVP_DIGESTINIT_EX, FIPS_R_FIPS_SELFTEST_FAILED);
279        ctx->digest = &bad_md;
280        return 0;
281    }
282#endif
283#ifndef OPENSSL_NO_ENGINE
284    /*
285     * Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
286     * this context may already have an ENGINE! Try to avoid releasing the
287     * previous handle, re-querying for an ENGINE, and having a
288     * reinitialisation, when it may all be unecessary.
289     */
290    if (ctx->engine && ctx->digest && (!type ||
291                                       (type
292                                        && (type->type ==
293                                            ctx->digest->type))))
294        goto skip_to_init;
295    if (!do_evp_md_engine(ctx, &type, impl))
296        return 0;
297#endif
298    if (ctx->digest != type) {
299#ifdef OPENSSL_FIPS
300        if (FIPS_mode()) {
301            if (!(type->flags & EVP_MD_FLAG_FIPS)
302                && !(ctx->flags & EVP_MD_CTX_FLAG_NON_FIPS_ALLOW)) {
303                EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_DISABLED_FOR_FIPS);
304                ctx->digest = &bad_md;
305                return 0;
306            }
307        }
308#endif
309        if (ctx->digest && ctx->digest->ctx_size)
310            OPENSSL_free(ctx->md_data);
311        ctx->digest = type;
312        if (type->ctx_size) {
313            ctx->md_data = OPENSSL_malloc(type->ctx_size);
314            if (!ctx->md_data) {
315                EVPerr(EVP_F_EVP_DIGESTINIT_EX, ERR_R_MALLOC_FAILURE);
316                return 0;
317            }
318        }
319    }
320#ifndef OPENSSL_NO_ENGINE
321 skip_to_init:
322#endif
323    return ctx->digest->init(ctx);
324}
325
326int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data, size_t count)
327{
328#ifdef OPENSSL_FIPS
329    FIPS_selftest_check();
330#endif
331    return ctx->digest->update(ctx, data, count);
332}
333
334/* The caller can assume that this removes any secret data from the context */
335int EVP_DigestFinal(EVP_MD_CTX *ctx, unsigned char *md, unsigned int *size)
336{
337    int ret;
338    ret = EVP_DigestFinal_ex(ctx, md, size);
339    EVP_MD_CTX_cleanup(ctx);
340    return ret;
341}
342
343/* The caller can assume that this removes any secret data from the context */
344int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, unsigned char *md, unsigned int *size)
345{
346    int ret;
347#ifdef OPENSSL_FIPS
348    FIPS_selftest_check();
349#endif
350
351    OPENSSL_assert(ctx->digest->md_size <= EVP_MAX_MD_SIZE);
352    ret = ctx->digest->final(ctx, md);
353    if (size != NULL)
354        *size = ctx->digest->md_size;
355    if (ctx->digest->cleanup) {
356        ctx->digest->cleanup(ctx);
357        M_EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
358    }
359    memset(ctx->md_data, 0, ctx->digest->ctx_size);
360    return ret;
361}
362
363int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in)
364{
365    EVP_MD_CTX_init(out);
366    return EVP_MD_CTX_copy_ex(out, in);
367}
368
369int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in)
370{
371    unsigned char *tmp_buf;
372    if ((in == NULL) || (in->digest == NULL)) {
373        EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, EVP_R_INPUT_NOT_INITIALIZED);
374        return 0;
375    }
376#ifndef OPENSSL_NO_ENGINE
377    /* Make sure it's safe to copy a digest context using an ENGINE */
378    if (in->engine && !do_engine_init(in->engine)) {
379        EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, ERR_R_ENGINE_LIB);
380        return 0;
381    }
382#endif
383
384    if (out->digest == in->digest) {
385        tmp_buf = out->md_data;
386        M_EVP_MD_CTX_set_flags(out, EVP_MD_CTX_FLAG_REUSE);
387    } else
388        tmp_buf = NULL;
389    EVP_MD_CTX_cleanup(out);
390    memcpy(out, in, sizeof *out);
391
392    if (out->digest->ctx_size) {
393        if (tmp_buf)
394            out->md_data = tmp_buf;
395        else {
396            out->md_data = OPENSSL_malloc(out->digest->ctx_size);
397            if (!out->md_data) {
398                EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, ERR_R_MALLOC_FAILURE);
399                return 0;
400            }
401        }
402        memcpy(out->md_data, in->md_data, out->digest->ctx_size);
403    }
404
405    if (out->digest->copy)
406        return out->digest->copy(out, in);
407
408    return 1;
409}
410
411int EVP_Digest(const void *data, size_t count,
412               unsigned char *md, unsigned int *size, const EVP_MD *type,
413               ENGINE *impl)
414{
415    EVP_MD_CTX ctx;
416    int ret;
417
418    EVP_MD_CTX_init(&ctx);
419    M_EVP_MD_CTX_set_flags(&ctx, EVP_MD_CTX_FLAG_ONESHOT);
420    ret = EVP_DigestInit_ex(&ctx, type, impl)
421        && EVP_DigestUpdate(&ctx, data, count)
422        && EVP_DigestFinal_ex(&ctx, md, size);
423    EVP_MD_CTX_cleanup(&ctx);
424
425    return ret;
426}
427
428void EVP_MD_CTX_destroy(EVP_MD_CTX *ctx)
429{
430    EVP_MD_CTX_cleanup(ctx);
431    OPENSSL_free(ctx);
432}
433
434/* This call frees resources associated with the context */
435int EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx)
436{
437    /*
438     * Don't assume ctx->md_data was cleaned in EVP_Digest_Final, because
439     * sometimes only copies of the context are ever finalised.
440     */
441    if (ctx->digest && ctx->digest->cleanup
442        && !M_EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_CLEANED))
443        ctx->digest->cleanup(ctx);
444    if (ctx->digest && ctx->digest->ctx_size && ctx->md_data
445        && !M_EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_REUSE)) {
446        OPENSSL_cleanse(ctx->md_data, ctx->digest->ctx_size);
447        OPENSSL_free(ctx->md_data);
448    }
449#ifndef OPENSSL_NO_ENGINE
450    if (ctx->engine)
451        /*
452         * The EVP_MD we used belongs to an ENGINE, release the functional
453         * reference we held for this reason.
454         */
455        do_engine_finish(ctx->engine);
456#endif
457    memset(ctx, '\0', sizeof *ctx);
458
459    return 1;
460}
461