/src/openssl/crypto/hmac/hmac.c

Source (jump to first uncovered line)
/*
 * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

/*
 * HMAC low level APIs are deprecated for public use, but still ok for internal
 * use.
 */
#include "internal/deprecated.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "internal/cryptlib.h"
#include <openssl/opensslconf.h>
#include <openssl/hmac.h>
#include <openssl/core_names.h>
#include "hmac_local.h"

int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len,
                 const EVP_MD *md, ENGINE *impl)
{
    int rv = 0, reset = 0;
    int i, j;
    unsigned char pad[HMAC_MAX_MD_CBLOCK_SIZE];
    unsigned int keytmp_length;
    unsigned char keytmp[HMAC_MAX_MD_CBLOCK_SIZE];

    /* If we are changing MD then we must have a key */
    if (md != NULL && md != ctx->md && (key == NULL || len < 0))
        return 0;

    if (md != NULL)
        ctx->md = md;
    else if (ctx->md != NULL)
        md = ctx->md;
    else
        return 0;

    /*
     * The HMAC construction is not allowed to be used with the
     * extendable-output functions (XOF) shake128 and shake256.
     */
    if ((EVP_MD_get_flags(md) & EVP_MD_FLAG_XOF) != 0)
        return 0;

    if (key != NULL) {
        reset = 1;

        j = EVP_MD_get_block_size(md);
        if (!ossl_assert(j <= (int)sizeof(keytmp)))
            return 0;
        if (j < 0)
            return 0;
        if (j < len) {
            if (!EVP_DigestInit_ex(ctx->md_ctx, md, impl)
                    || !EVP_DigestUpdate(ctx->md_ctx, key, len)
                    || !EVP_DigestFinal_ex(ctx->md_ctx, keytmp,
                                           &keytmp_length))
                return 0;
        } else {
            if (len < 0 || len > (int)sizeof(keytmp))
                return 0;
            memcpy(keytmp, key, len);
            keytmp_length = len;
        }
        if (keytmp_length != HMAC_MAX_MD_CBLOCK_SIZE)
            memset(&keytmp[keytmp_length], 0,
                   HMAC_MAX_MD_CBLOCK_SIZE - keytmp_length);

        for (i = 0; i < HMAC_MAX_MD_CBLOCK_SIZE; i++)
            pad[i] = 0x36 ^ keytmp[i];
        if (!EVP_DigestInit_ex(ctx->i_ctx, md, impl)
                || !EVP_DigestUpdate(ctx->i_ctx, pad,
                                     EVP_MD_get_block_size(md)))
            goto err;

        for (i = 0; i < HMAC_MAX_MD_CBLOCK_SIZE; i++)
            pad[i] = 0x5c ^ keytmp[i];
        if (!EVP_DigestInit_ex(ctx->o_ctx, md, impl)
                || !EVP_DigestUpdate(ctx->o_ctx, pad,
                                     EVP_MD_get_block_size(md)))
            goto err;
    }
    if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->i_ctx))
        goto err;
    rv = 1;
 err:
    if (reset) {
        OPENSSL_cleanse(keytmp, sizeof(keytmp));
        OPENSSL_cleanse(pad, sizeof(pad));
    }
    return rv;
}

#ifndef OPENSSL_NO_DEPRECATED_1_1_0
int HMAC_Init(HMAC_CTX *ctx, const void *key, int len, const EVP_MD *md)
{
    if (key && md)
        HMAC_CTX_reset(ctx);
    return HMAC_Init_ex(ctx, key, len, md, NULL);
}
#endif

int HMAC_Update(HMAC_CTX *ctx, const unsigned char *data, size_t len)
{
    if (!ctx->md)
        return 0;
    return EVP_DigestUpdate(ctx->md_ctx, data, len);
}

int HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len)
{
    unsigned int i;
    unsigned char buf[EVP_MAX_MD_SIZE];

    if (!ctx->md)
        goto err;

    if (!EVP_DigestFinal_ex(ctx->md_ctx, buf, &i))
        goto err;
    if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->o_ctx))
        goto err;
    if (!EVP_DigestUpdate(ctx->md_ctx, buf, i))
        goto err;
    if (!EVP_DigestFinal_ex(ctx->md_ctx, md, len))
        goto err;
    return 1;
 err:
    return 0;
}

size_t HMAC_size(const HMAC_CTX *ctx)
{
    int size = EVP_MD_get_size((ctx)->md);

    return (size < 0) ? 0 : size;
}

HMAC_CTX *HMAC_CTX_new(void)
{
    HMAC_CTX *ctx = OPENSSL_zalloc(sizeof(HMAC_CTX));

    if (ctx != NULL) {
        if (!HMAC_CTX_reset(ctx)) {
            HMAC_CTX_free(ctx);
            return NULL;
        }
    }
    return ctx;
}

static void hmac_ctx_cleanup(HMAC_CTX *ctx)
{
    EVP_MD_CTX_reset(ctx->i_ctx);
    EVP_MD_CTX_reset(ctx->o_ctx);
    EVP_MD_CTX_reset(ctx->md_ctx);
    ctx->md = NULL;
}

void HMAC_CTX_free(HMAC_CTX *ctx)
{
    if (ctx != NULL) {
        hmac_ctx_cleanup(ctx);
        EVP_MD_CTX_free(ctx->i_ctx);
        EVP_MD_CTX_free(ctx->o_ctx);
        EVP_MD_CTX_free(ctx->md_ctx);
        OPENSSL_free(ctx);
    }
}

static int hmac_ctx_alloc_mds(HMAC_CTX *ctx)
{
    if (ctx->i_ctx == NULL)
        ctx->i_ctx = EVP_MD_CTX_new();
    if (ctx->i_ctx == NULL)
        return 0;
    if (ctx->o_ctx == NULL)
        ctx->o_ctx = EVP_MD_CTX_new();
    if (ctx->o_ctx == NULL)
        return 0;
    if (ctx->md_ctx == NULL)
        ctx->md_ctx = EVP_MD_CTX_new();
    if (ctx->md_ctx == NULL)
        return 0;
    return 1;
}

int HMAC_CTX_reset(HMAC_CTX *ctx)
{
    hmac_ctx_cleanup(ctx);
    if (!hmac_ctx_alloc_mds(ctx)) {
        hmac_ctx_cleanup(ctx);
        return 0;
    }
    return 1;
}

int HMAC_CTX_copy(HMAC_CTX *dctx, HMAC_CTX *sctx)
{
    if (!hmac_ctx_alloc_mds(dctx))
        goto err;
    if (!EVP_MD_CTX_copy_ex(dctx->i_ctx, sctx->i_ctx))
        goto err;
    if (!EVP_MD_CTX_copy_ex(dctx->o_ctx, sctx->o_ctx))
        goto err;
    if (!EVP_MD_CTX_copy_ex(dctx->md_ctx, sctx->md_ctx))
        goto err;
    dctx->md = sctx->md;
    return 1;
 err:
    hmac_ctx_cleanup(dctx);
    return 0;
}

unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len,
                    const unsigned char *data, size_t data_len,
                    unsigned char *md, unsigned int *md_len)
{
    static unsigned char static_md[EVP_MAX_MD_SIZE];
    int size = EVP_MD_get_size(evp_md);
    size_t temp_md_len = 0;
    unsigned char *ret = NULL;

    if (size >= 0) {
        ret = EVP_Q_mac(NULL, "HMAC", NULL, EVP_MD_get0_name(evp_md), NULL,
                        key, key_len, data, data_len,
                        md == NULL ? static_md : md, size, &temp_md_len);
        if (md_len != NULL)
            *md_len = (unsigned int)temp_md_len;
    }
    return ret;
}

void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags)
{
    EVP_MD_CTX_set_flags(ctx->i_ctx, flags);
    EVP_MD_CTX_set_flags(ctx->o_ctx, flags);
    EVP_MD_CTX_set_flags(ctx->md_ctx, flags);
}

const EVP_MD *HMAC_CTX_get_md(const HMAC_CTX *ctx)
{
    return ctx->md;
}

Coverage Report

Created: 2023-06-08 06:40

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 1995-2021 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		/*
11		* HMAC low level APIs are deprecated for public use, but still ok for internal
12		* use.
13		*/
14		#include "internal/deprecated.h"
15
16		#include <stdio.h>
17		#include <stdlib.h>
18		#include <string.h>
19		#include "internal/cryptlib.h"
20		#include <openssl/opensslconf.h>
21		#include <openssl/hmac.h>
22		#include <openssl/core_names.h>
23		#include "hmac_local.h"
24
25		int HMAC_Init_ex(HMAC_CTX ctx, const void key, int len,
26		const EVP_MD md, ENGINE impl)
27	0	{
28	0	int rv = 0, reset = 0;
29	0	int i, j;
30	0	unsigned char pad[HMAC_MAX_MD_CBLOCK_SIZE];
31	0	unsigned int keytmp_length;
32	0	unsigned char keytmp[HMAC_MAX_MD_CBLOCK_SIZE];
33
34		/* If we are changing MD then we must have a key */
35	0	if (md != NULL && md != ctx->md && (key == NULL \|\| len < 0))
36	0	return 0;
37
38	0	if (md != NULL)
39	0	ctx->md = md;
40	0	else if (ctx->md != NULL)
41	0	md = ctx->md;
42	0	else
43	0	return 0;
44
45		/*
46		* The HMAC construction is not allowed to be used with the
47		* extendable-output functions (XOF) shake128 and shake256.
48		*/
49	0	if ((EVP_MD_get_flags(md) & EVP_MD_FLAG_XOF) != 0)
50	0	return 0;
51
52	0	if (key != NULL) {
53	0	reset = 1;
54
55	0	j = EVP_MD_get_block_size(md);
56	0	if (!ossl_assert(j <= (int)sizeof(keytmp)))
57	0	return 0;
58	0	if (j < 0)
59	0	return 0;
60	0	if (j < len) {
61	0	if (!EVP_DigestInit_ex(ctx->md_ctx, md, impl)
62	0	\|\| !EVP_DigestUpdate(ctx->md_ctx, key, len)
63	0	\|\| !EVP_DigestFinal_ex(ctx->md_ctx, keytmp,
64	0	&keytmp_length))
65	0	return 0;
66	0	} else {
67	0	if (len < 0 \|\| len > (int)sizeof(keytmp))
68	0	return 0;
69	0	memcpy(keytmp, key, len);
70	0	keytmp_length = len;
71	0	}
72	0	if (keytmp_length != HMAC_MAX_MD_CBLOCK_SIZE)
73	0	memset(&keytmp[keytmp_length], 0,
74	0	HMAC_MAX_MD_CBLOCK_SIZE - keytmp_length);
75
76	0	for (i = 0; i < HMAC_MAX_MD_CBLOCK_SIZE; i++)
77	0	pad[i] = 0x36 ^ keytmp[i];
78	0	if (!EVP_DigestInit_ex(ctx->i_ctx, md, impl)
79	0	\|\| !EVP_DigestUpdate(ctx->i_ctx, pad,
80	0	EVP_MD_get_block_size(md)))
81	0	goto err;
82
83	0	for (i = 0; i < HMAC_MAX_MD_CBLOCK_SIZE; i++)
84	0	pad[i] = 0x5c ^ keytmp[i];
85	0	if (!EVP_DigestInit_ex(ctx->o_ctx, md, impl)
86	0	\|\| !EVP_DigestUpdate(ctx->o_ctx, pad,
87	0	EVP_MD_get_block_size(md)))
88	0	goto err;
89	0	}
90	0	if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->i_ctx))
91	0	goto err;
92	0	rv = 1;
93	0	err:
94	0	if (reset) {
95	0	OPENSSL_cleanse(keytmp, sizeof(keytmp));
96	0	OPENSSL_cleanse(pad, sizeof(pad));
97	0	}
98	0	return rv;
99	0	}
100
101		#ifndef OPENSSL_NO_DEPRECATED_1_1_0
102		int HMAC_Init(HMAC_CTX ctx, const void key, int len, const EVP_MD *md)
103	0	{
104	0	if (key && md)
105	0	HMAC_CTX_reset(ctx);
106	0	return HMAC_Init_ex(ctx, key, len, md, NULL);
107	0	}
108		#endif
109
110		int HMAC_Update(HMAC_CTX ctx, const unsigned char data, size_t len)
111	0	{
112	0	if (!ctx->md)
113	0	return 0;
114	0	return EVP_DigestUpdate(ctx->md_ctx, data, len);
115	0	}
116
117		int HMAC_Final(HMAC_CTX ctx, unsigned char md, unsigned int *len)
118	0	{
119	0	unsigned int i;
120	0	unsigned char buf[EVP_MAX_MD_SIZE];
121
122	0	if (!ctx->md)
123	0	goto err;
124
125	0	if (!EVP_DigestFinal_ex(ctx->md_ctx, buf, &i))
126	0	goto err;
127	0	if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->o_ctx))
128	0	goto err;
129	0	if (!EVP_DigestUpdate(ctx->md_ctx, buf, i))
130	0	goto err;
131	0	if (!EVP_DigestFinal_ex(ctx->md_ctx, md, len))
132	0	goto err;
133	0	return 1;
134	0	err:
135	0	return 0;
136	0	}
137
138		size_t HMAC_size(const HMAC_CTX *ctx)
139	0	{
140	0	int size = EVP_MD_get_size((ctx)->md);
141
142	0	return (size < 0) ? 0 : size;
143	0	}
144
145		HMAC_CTX *HMAC_CTX_new(void)
146	0	{
147	0	HMAC_CTX *ctx = OPENSSL_zalloc(sizeof(HMAC_CTX));
148
149	0	if (ctx != NULL) {
150	0	if (!HMAC_CTX_reset(ctx)) {
151	0	HMAC_CTX_free(ctx);
152	0	return NULL;
153	0	}
154	0	}
155	0	return ctx;
156	0	}
157
158		static void hmac_ctx_cleanup(HMAC_CTX *ctx)
159	0	{
160	0	EVP_MD_CTX_reset(ctx->i_ctx);
161	0	EVP_MD_CTX_reset(ctx->o_ctx);
162	0	EVP_MD_CTX_reset(ctx->md_ctx);
163	0	ctx->md = NULL;
164	0	}
165
166		void HMAC_CTX_free(HMAC_CTX *ctx)
167	0	{
168	0	if (ctx != NULL) {
169	0	hmac_ctx_cleanup(ctx);
170	0	EVP_MD_CTX_free(ctx->i_ctx);
171	0	EVP_MD_CTX_free(ctx->o_ctx);
172	0	EVP_MD_CTX_free(ctx->md_ctx);
173	0	OPENSSL_free(ctx);
174	0	}
175	0	}
176
177		static int hmac_ctx_alloc_mds(HMAC_CTX *ctx)
178	0	{
179	0	if (ctx->i_ctx == NULL)
180	0	ctx->i_ctx = EVP_MD_CTX_new();
181	0	if (ctx->i_ctx == NULL)
182	0	return 0;
183	0	if (ctx->o_ctx == NULL)
184	0	ctx->o_ctx = EVP_MD_CTX_new();
185	0	if (ctx->o_ctx == NULL)
186	0	return 0;
187	0	if (ctx->md_ctx == NULL)
188	0	ctx->md_ctx = EVP_MD_CTX_new();
189	0	if (ctx->md_ctx == NULL)
190	0	return 0;
191	0	return 1;
192	0	}
193
194		int HMAC_CTX_reset(HMAC_CTX *ctx)
195	0	{
196	0	hmac_ctx_cleanup(ctx);
197	0	if (!hmac_ctx_alloc_mds(ctx)) {
198	0	hmac_ctx_cleanup(ctx);
199	0	return 0;
200	0	}
201	0	return 1;
202	0	}
203
204		int HMAC_CTX_copy(HMAC_CTX dctx, HMAC_CTX sctx)
205	0	{
206	0	if (!hmac_ctx_alloc_mds(dctx))
207	0	goto err;
208	0	if (!EVP_MD_CTX_copy_ex(dctx->i_ctx, sctx->i_ctx))
209	0	goto err;
210	0	if (!EVP_MD_CTX_copy_ex(dctx->o_ctx, sctx->o_ctx))
211	0	goto err;
212	0	if (!EVP_MD_CTX_copy_ex(dctx->md_ctx, sctx->md_ctx))
213	0	goto err;
214	0	dctx->md = sctx->md;
215	0	return 1;
216	0	err:
217	0	hmac_ctx_cleanup(dctx);
218	0	return 0;
219	0	}
220
221		unsigned char HMAC(const EVP_MD evp_md, const void *key, int key_len,
222		const unsigned char *data, size_t data_len,
223		unsigned char md, unsigned int md_len)
224	0	{
225	0	static unsigned char static_md[EVP_MAX_MD_SIZE];
226	0	int size = EVP_MD_get_size(evp_md);
227	0	size_t temp_md_len = 0;
228	0	unsigned char *ret = NULL;
229
230	0	if (size >= 0) {
231	0	ret = EVP_Q_mac(NULL, "HMAC", NULL, EVP_MD_get0_name(evp_md), NULL,
232	0	key, key_len, data, data_len,
233	0	md == NULL ? static_md : md, size, &temp_md_len);
234	0	if (md_len != NULL)
235	0	*md_len = (unsigned int)temp_md_len;
236	0	}
237	0	return ret;
238	0	}
239
240		void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags)
241	0	{
242	0	EVP_MD_CTX_set_flags(ctx->i_ctx, flags);
243	0	EVP_MD_CTX_set_flags(ctx->o_ctx, flags);
244	0	EVP_MD_CTX_set_flags(ctx->md_ctx, flags);
245	0	}
246
247		const EVP_MD HMAC_CTX_get_md(const HMAC_CTX ctx)
248	0	{
249	0	return ctx->md;
250	0	}