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

Source (jump to first uncovered line)
/*
 * Copyright 1995-2018 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/hmac.h>
#include <openssl/opensslconf.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) {
        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_flags(md) & EVP_MD_FLAG_XOF) != 0)
        return 0;

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

        j = EVP_MD_block_size(md);
        if (!ossl_assert(j <= (int)sizeof(keytmp)))
            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_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_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_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 *d, size_t n, unsigned char *md,
                    unsigned int *md_len)
{
    HMAC_CTX *c = NULL;
    static unsigned char m[EVP_MAX_MD_SIZE];
    static const unsigned char dummy_key[1] = {'\0'};

    if (md == NULL)
        md = m;
    if ((c = HMAC_CTX_new()) == NULL)
        goto err;

    /* For HMAC_Init_ex, NULL key signals reuse. */
    if (key == NULL && key_len == 0) {
        key = dummy_key;
    }

    if (!HMAC_Init_ex(c, key, key_len, evp_md, NULL))
        goto err;
    if (!HMAC_Update(c, d, n))
        goto err;
    if (!HMAC_Final(c, md, md_len))
        goto err;
    HMAC_CTX_free(c);
    return md;
 err:
    HMAC_CTX_free(c);
    return NULL;
}

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: 2024-05-15 07:16

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 1995-2018 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/hmac.h>
21		#include <openssl/opensslconf.h>
22		#include "hmac_local.h"
23
24		int HMAC_Init_ex(HMAC_CTX ctx, const void key, int len,
25		const EVP_MD md, ENGINE impl)
26	0	{
27	0	int rv = 0, reset = 0;
28	0	int i, j;
29	0	unsigned char pad[HMAC_MAX_MD_CBLOCK_SIZE];
30	0	unsigned int keytmp_length;
31	0	unsigned char keytmp[HMAC_MAX_MD_CBLOCK_SIZE];
32
33		/* If we are changing MD then we must have a key */
34	0	if (md != NULL && md != ctx->md && (key == NULL \|\| len < 0))
35	0	return 0;
36
37	0	if (md != NULL) {
38	0	ctx->md = md;
39	0	} else if (ctx->md) {
40	0	md = ctx->md;
41	0	} else {
42	0	return 0;
43	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_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_block_size(md);
56	0	if (!ossl_assert(j <= (int)sizeof(keytmp)))
57	0	return 0;
58	0	if (j < len) {
59	0	if (!EVP_DigestInit_ex(ctx->md_ctx, md, impl)
60	0	\|\| !EVP_DigestUpdate(ctx->md_ctx, key, len)
61	0	\|\| !EVP_DigestFinal_ex(ctx->md_ctx, keytmp,
62	0	&keytmp_length))
63	0	return 0;
64	0	} else {
65	0	if (len < 0 \|\| len > (int)sizeof(keytmp))
66	0	return 0;
67	0	memcpy(keytmp, key, len);
68	0	keytmp_length = len;
69	0	}
70	0	if (keytmp_length != HMAC_MAX_MD_CBLOCK_SIZE)
71	0	memset(&keytmp[keytmp_length], 0,
72	0	HMAC_MAX_MD_CBLOCK_SIZE - keytmp_length);
73
74	0	for (i = 0; i < HMAC_MAX_MD_CBLOCK_SIZE; i++)
75	0	pad[i] = 0x36 ^ keytmp[i];
76	0	if (!EVP_DigestInit_ex(ctx->i_ctx, md, impl)
77	0	\|\| !EVP_DigestUpdate(ctx->i_ctx, pad, EVP_MD_block_size(md)))
78	0	goto err;
79
80	0	for (i = 0; i < HMAC_MAX_MD_CBLOCK_SIZE; i++)
81	0	pad[i] = 0x5c ^ keytmp[i];
82	0	if (!EVP_DigestInit_ex(ctx->o_ctx, md, impl)
83	0	\|\| !EVP_DigestUpdate(ctx->o_ctx, pad, EVP_MD_block_size(md)))
84	0	goto err;
85	0	}
86	0	if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->i_ctx))
87	0	goto err;
88	0	rv = 1;
89	0	err:
90	0	if (reset) {
91	0	OPENSSL_cleanse(keytmp, sizeof(keytmp));
92	0	OPENSSL_cleanse(pad, sizeof(pad));
93	0	}
94	0	return rv;
95	0	}
96
97		#ifndef OPENSSL_NO_DEPRECATED_1_1_0
98		int HMAC_Init(HMAC_CTX ctx, const void key, int len, const EVP_MD *md)
99	0	{
100	0	if (key && md)
101	0	HMAC_CTX_reset(ctx);
102	0	return HMAC_Init_ex(ctx, key, len, md, NULL);
103	0	}
104		#endif
105
106		int HMAC_Update(HMAC_CTX ctx, const unsigned char data, size_t len)
107	0	{
108	0	if (!ctx->md)
109	0	return 0;
110	0	return EVP_DigestUpdate(ctx->md_ctx, data, len);
111	0	}
112
113		int HMAC_Final(HMAC_CTX ctx, unsigned char md, unsigned int *len)
114	0	{
115	0	unsigned int i;
116	0	unsigned char buf[EVP_MAX_MD_SIZE];
117
118	0	if (!ctx->md)
119	0	goto err;
120
121	0	if (!EVP_DigestFinal_ex(ctx->md_ctx, buf, &i))
122	0	goto err;
123	0	if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->o_ctx))
124	0	goto err;
125	0	if (!EVP_DigestUpdate(ctx->md_ctx, buf, i))
126	0	goto err;
127	0	if (!EVP_DigestFinal_ex(ctx->md_ctx, md, len))
128	0	goto err;
129	0	return 1;
130	0	err:
131	0	return 0;
132	0	}
133
134		size_t HMAC_size(const HMAC_CTX *ctx)
135	0	{
136	0	int size = EVP_MD_size((ctx)->md);
137
138	0	return (size < 0) ? 0 : size;
139	0	}
140
141		HMAC_CTX *HMAC_CTX_new(void)
142	0	{
143	0	HMAC_CTX *ctx = OPENSSL_zalloc(sizeof(HMAC_CTX));
144
145	0	if (ctx != NULL) {
146	0	if (!HMAC_CTX_reset(ctx)) {
147	0	HMAC_CTX_free(ctx);
148	0	return NULL;
149	0	}
150	0	}
151	0	return ctx;
152	0	}
153
154		static void hmac_ctx_cleanup(HMAC_CTX *ctx)
155	0	{
156	0	EVP_MD_CTX_reset(ctx->i_ctx);
157	0	EVP_MD_CTX_reset(ctx->o_ctx);
158	0	EVP_MD_CTX_reset(ctx->md_ctx);
159	0	ctx->md = NULL;
160	0	}
161
162		void HMAC_CTX_free(HMAC_CTX *ctx)
163	0	{
164	0	if (ctx != NULL) {
165	0	hmac_ctx_cleanup(ctx);
166	0	EVP_MD_CTX_free(ctx->i_ctx);
167	0	EVP_MD_CTX_free(ctx->o_ctx);
168	0	EVP_MD_CTX_free(ctx->md_ctx);
169	0	OPENSSL_free(ctx);
170	0	}
171	0	}
172
173		static int hmac_ctx_alloc_mds(HMAC_CTX *ctx)
174	0	{
175	0	if (ctx->i_ctx == NULL)
176	0	ctx->i_ctx = EVP_MD_CTX_new();
177	0	if (ctx->i_ctx == NULL)
178	0	return 0;
179	0	if (ctx->o_ctx == NULL)
180	0	ctx->o_ctx = EVP_MD_CTX_new();
181	0	if (ctx->o_ctx == NULL)
182	0	return 0;
183	0	if (ctx->md_ctx == NULL)
184	0	ctx->md_ctx = EVP_MD_CTX_new();
185	0	if (ctx->md_ctx == NULL)
186	0	return 0;
187	0	return 1;
188	0	}
189
190		int HMAC_CTX_reset(HMAC_CTX *ctx)
191	0	{
192	0	hmac_ctx_cleanup(ctx);
193	0	if (!hmac_ctx_alloc_mds(ctx)) {
194	0	hmac_ctx_cleanup(ctx);
195	0	return 0;
196	0	}
197	0	return 1;
198	0	}
199
200		int HMAC_CTX_copy(HMAC_CTX dctx, HMAC_CTX sctx)
201	0	{
202	0	if (!hmac_ctx_alloc_mds(dctx))
203	0	goto err;
204	0	if (!EVP_MD_CTX_copy_ex(dctx->i_ctx, sctx->i_ctx))
205	0	goto err;
206	0	if (!EVP_MD_CTX_copy_ex(dctx->o_ctx, sctx->o_ctx))
207	0	goto err;
208	0	if (!EVP_MD_CTX_copy_ex(dctx->md_ctx, sctx->md_ctx))
209	0	goto err;
210	0	dctx->md = sctx->md;
211	0	return 1;
212	0	err:
213	0	hmac_ctx_cleanup(dctx);
214	0	return 0;
215	0	}
216
217		unsigned char HMAC(const EVP_MD evp_md, const void *key, int key_len,
218		const unsigned char d, size_t n, unsigned char md,
219		unsigned int *md_len)
220	0	{
221	0	HMAC_CTX *c = NULL;
222	0	static unsigned char m[EVP_MAX_MD_SIZE];
223	0	static const unsigned char dummy_key[1] = {'\0'};
224
225	0	if (md == NULL)
226	0	md = m;
227	0	if ((c = HMAC_CTX_new()) == NULL)
228	0	goto err;
229
230		/* For HMAC_Init_ex, NULL key signals reuse. */
231	0	if (key == NULL && key_len == 0) {
232	0	key = dummy_key;
233	0	}
234
235	0	if (!HMAC_Init_ex(c, key, key_len, evp_md, NULL))
236	0	goto err;
237	0	if (!HMAC_Update(c, d, n))
238	0	goto err;
239	0	if (!HMAC_Final(c, md, md_len))
240	0	goto err;
241	0	HMAC_CTX_free(c);
242	0	return md;
243	0	err:
244	0	HMAC_CTX_free(c);
245	0	return NULL;
246	0	}
247
248		void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags)
249	0	{
250	0	EVP_MD_CTX_set_flags(ctx->i_ctx, flags);
251	0	EVP_MD_CTX_set_flags(ctx->o_ctx, flags);
252	0	EVP_MD_CTX_set_flags(ctx->md_ctx, flags);
253	0	}
254
255		const EVP_MD HMAC_CTX_get_md(const HMAC_CTX ctx)
256	0	{
257	0	return ctx->md;
258	0	}