/src/openssl111/crypto/hmac/hmac.c

Source (jump to first uncovered line)
/*
 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the OpenSSL license (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
 */

#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_meth_get_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;
}

#if OPENSSL_API_COMPAT < 0x10100000L
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: 2023-06-08 06:41

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
3		*
4		* Licensed under the OpenSSL license (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 <stdio.h>
11		#include <stdlib.h>
12		#include <string.h>
13		#include "internal/cryptlib.h"
14		#include <openssl/hmac.h>
15		#include <openssl/opensslconf.h>
16		#include "hmac_local.h"
17
18		int HMAC_Init_ex(HMAC_CTX ctx, const void key, int len,
19		const EVP_MD md, ENGINE impl)
20	0	{
21	0	int rv = 0, reset = 0;
22	0	int i, j;
23	0	unsigned char pad[HMAC_MAX_MD_CBLOCK_SIZE];
24	0	unsigned int keytmp_length;
25	0	unsigned char keytmp[HMAC_MAX_MD_CBLOCK_SIZE];
26
27		/* If we are changing MD then we must have a key */
28	0	if (md != NULL && md != ctx->md && (key == NULL \|\| len < 0))
29	0	return 0;
30
31	0	if (md != NULL) {
32	0	ctx->md = md;
33	0	} else if (ctx->md) {
34	0	md = ctx->md;
35	0	} else {
36	0	return 0;
37	0	}
38
39		/*
40		* The HMAC construction is not allowed to be used with the
41		* extendable-output functions (XOF) shake128 and shake256.
42		*/
43	0	if ((EVP_MD_meth_get_flags(md) & EVP_MD_FLAG_XOF) != 0)
44	0	return 0;
45
46	0	if (key != NULL) {
47	0	reset = 1;
48
49	0	j = EVP_MD_block_size(md);
50	0	if (!ossl_assert(j <= (int)sizeof(keytmp)))
51	0	return 0;
52	0	if (j < len) {
53	0	if (!EVP_DigestInit_ex(ctx->md_ctx, md, impl)
54	0	\|\| !EVP_DigestUpdate(ctx->md_ctx, key, len)
55	0	\|\| !EVP_DigestFinal_ex(ctx->md_ctx, keytmp,
56	0	&keytmp_length))
57	0	return 0;
58	0	} else {
59	0	if (len < 0 \|\| len > (int)sizeof(keytmp))
60	0	return 0;
61	0	memcpy(keytmp, key, len);
62	0	keytmp_length = len;
63	0	}
64	0	if (keytmp_length != HMAC_MAX_MD_CBLOCK_SIZE)
65	0	memset(&keytmp[keytmp_length], 0,
66	0	HMAC_MAX_MD_CBLOCK_SIZE - keytmp_length);
67
68	0	for (i = 0; i < HMAC_MAX_MD_CBLOCK_SIZE; i++)
69	0	pad[i] = 0x36 ^ keytmp[i];
70	0	if (!EVP_DigestInit_ex(ctx->i_ctx, md, impl)
71	0	\|\| !EVP_DigestUpdate(ctx->i_ctx, pad, EVP_MD_block_size(md)))
72	0	goto err;
73
74	0	for (i = 0; i < HMAC_MAX_MD_CBLOCK_SIZE; i++)
75	0	pad[i] = 0x5c ^ keytmp[i];
76	0	if (!EVP_DigestInit_ex(ctx->o_ctx, md, impl)
77	0	\|\| !EVP_DigestUpdate(ctx->o_ctx, pad, EVP_MD_block_size(md)))
78	0	goto err;
79	0	}
80	0	if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->i_ctx))
81	0	goto err;
82	0	rv = 1;
83	0	err:
84	0	if (reset) {
85	0	OPENSSL_cleanse(keytmp, sizeof(keytmp));
86	0	OPENSSL_cleanse(pad, sizeof(pad));
87	0	}
88	0	return rv;
89	0	}
90
91		#if OPENSSL_API_COMPAT < 0x10100000L
92		int HMAC_Init(HMAC_CTX ctx, const void key, int len, const EVP_MD *md)
93	0	{
94	0	if (key && md)
95	0	HMAC_CTX_reset(ctx);
96	0	return HMAC_Init_ex(ctx, key, len, md, NULL);
97	0	}
98		#endif
99
100		int HMAC_Update(HMAC_CTX ctx, const unsigned char data, size_t len)
101	0	{
102	0	if (!ctx->md)
103	0	return 0;
104	0	return EVP_DigestUpdate(ctx->md_ctx, data, len);
105	0	}
106
107		int HMAC_Final(HMAC_CTX ctx, unsigned char md, unsigned int *len)
108	0	{
109	0	unsigned int i;
110	0	unsigned char buf[EVP_MAX_MD_SIZE];
111
112	0	if (!ctx->md)
113	0	goto err;
114
115	0	if (!EVP_DigestFinal_ex(ctx->md_ctx, buf, &i))
116	0	goto err;
117	0	if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->o_ctx))
118	0	goto err;
119	0	if (!EVP_DigestUpdate(ctx->md_ctx, buf, i))
120	0	goto err;
121	0	if (!EVP_DigestFinal_ex(ctx->md_ctx, md, len))
122	0	goto err;
123	0	return 1;
124	0	err:
125	0	return 0;
126	0	}
127
128		size_t HMAC_size(const HMAC_CTX *ctx)
129	0	{
130	0	int size = EVP_MD_size((ctx)->md);
131
132	0	return (size < 0) ? 0 : size;
133	0	}
134
135		HMAC_CTX *HMAC_CTX_new(void)
136	0	{
137	0	HMAC_CTX *ctx = OPENSSL_zalloc(sizeof(HMAC_CTX));
138
139	0	if (ctx != NULL) {
140	0	if (!HMAC_CTX_reset(ctx)) {
141	0	HMAC_CTX_free(ctx);
142	0	return NULL;
143	0	}
144	0	}
145	0	return ctx;
146	0	}
147
148		static void hmac_ctx_cleanup(HMAC_CTX *ctx)
149	0	{
150	0	EVP_MD_CTX_reset(ctx->i_ctx);
151	0	EVP_MD_CTX_reset(ctx->o_ctx);
152	0	EVP_MD_CTX_reset(ctx->md_ctx);
153	0	ctx->md = NULL;
154	0	}
155
156		void HMAC_CTX_free(HMAC_CTX *ctx)
157	0	{
158	0	if (ctx != NULL) {
159	0	hmac_ctx_cleanup(ctx);
160	0	EVP_MD_CTX_free(ctx->i_ctx);
161	0	EVP_MD_CTX_free(ctx->o_ctx);
162	0	EVP_MD_CTX_free(ctx->md_ctx);
163	0	OPENSSL_free(ctx);
164	0	}
165	0	}
166
167		static int hmac_ctx_alloc_mds(HMAC_CTX *ctx)
168	0	{
169	0	if (ctx->i_ctx == NULL)
170	0	ctx->i_ctx = EVP_MD_CTX_new();
171	0	if (ctx->i_ctx == NULL)
172	0	return 0;
173	0	if (ctx->o_ctx == NULL)
174	0	ctx->o_ctx = EVP_MD_CTX_new();
175	0	if (ctx->o_ctx == NULL)
176	0	return 0;
177	0	if (ctx->md_ctx == NULL)
178	0	ctx->md_ctx = EVP_MD_CTX_new();
179	0	if (ctx->md_ctx == NULL)
180	0	return 0;
181	0	return 1;
182	0	}
183
184		int HMAC_CTX_reset(HMAC_CTX *ctx)
185	0	{
186	0	hmac_ctx_cleanup(ctx);
187	0	if (!hmac_ctx_alloc_mds(ctx)) {
188	0	hmac_ctx_cleanup(ctx);
189	0	return 0;
190	0	}
191	0	return 1;
192	0	}
193
194		int HMAC_CTX_copy(HMAC_CTX dctx, HMAC_CTX sctx)
195	0	{
196	0	if (!hmac_ctx_alloc_mds(dctx))
197	0	goto err;
198	0	if (!EVP_MD_CTX_copy_ex(dctx->i_ctx, sctx->i_ctx))
199	0	goto err;
200	0	if (!EVP_MD_CTX_copy_ex(dctx->o_ctx, sctx->o_ctx))
201	0	goto err;
202	0	if (!EVP_MD_CTX_copy_ex(dctx->md_ctx, sctx->md_ctx))
203	0	goto err;
204	0	dctx->md = sctx->md;
205	0	return 1;
206	0	err:
207	0	hmac_ctx_cleanup(dctx);
208	0	return 0;
209	0	}
210
211		unsigned char HMAC(const EVP_MD evp_md, const void *key, int key_len,
212		const unsigned char d, size_t n, unsigned char md,
213		unsigned int *md_len)
214	0	{
215	0	HMAC_CTX *c = NULL;
216	0	static unsigned char m[EVP_MAX_MD_SIZE];
217	0	static const unsigned char dummy_key[1] = {'\0'};
218
219	0	if (md == NULL)
220	0	md = m;
221	0	if ((c = HMAC_CTX_new()) == NULL)
222	0	goto err;
223
224		/* For HMAC_Init_ex, NULL key signals reuse. */
225	0	if (key == NULL && key_len == 0) {
226	0	key = dummy_key;
227	0	}
228
229	0	if (!HMAC_Init_ex(c, key, key_len, evp_md, NULL))
230	0	goto err;
231	0	if (!HMAC_Update(c, d, n))
232	0	goto err;
233	0	if (!HMAC_Final(c, md, md_len))
234	0	goto err;
235	0	HMAC_CTX_free(c);
236	0	return md;
237	0	err:
238	0	HMAC_CTX_free(c);
239	0	return NULL;
240	0	}
241
242		void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags)
243	0	{
244	0	EVP_MD_CTX_set_flags(ctx->i_ctx, flags);
245	0	EVP_MD_CTX_set_flags(ctx->o_ctx, flags);
246	0	EVP_MD_CTX_set_flags(ctx->md_ctx, flags);
247	0	}
248
249		const EVP_MD HMAC_CTX_get_md(const HMAC_CTX ctx)
250	0	{
251	0	return ctx->md;
252	0	}