/src/openssl30/providers/implementations/kdfs/kbkdf.c

Source (jump to first uncovered line)
/*
 * Copyright 2019-2022 The OpenSSL Project Authors. All Rights Reserved.
 * Copyright 2019 Red Hat, Inc.
 *
 * 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
 */

/*
 * This implements https://csrc.nist.gov/publications/detail/sp/800-108/final
 * section 5.1 ("counter mode") and section 5.2 ("feedback mode") in both HMAC
 * and CMAC.  That document does not name the KDFs it defines; the name is
 * derived from
 * https://csrc.nist.gov/Projects/Cryptographic-Algorithm-Validation-Program/Key-Derivation
 *
 * Note that section 5.3 ("double-pipeline mode") is not implemented, though
 * it would be possible to do so in the future.
 *
 * These versions all assume the counter is used.  It would be relatively
 * straightforward to expose a configuration handle should the need arise.
 *
 * Variable names attempt to match those of SP800-108.
 */

#include <stdarg.h>
#include <stdlib.h>
#include <string.h>

#include <openssl/core_names.h>
#include <openssl/evp.h>
#include <openssl/hmac.h>
#include <openssl/kdf.h>
#include <openssl/params.h>
#include <openssl/proverr.h>

#include "internal/cryptlib.h"
#include "crypto/evp.h"
#include "internal/numbers.h"
#include "internal/endian.h"
#include "prov/implementations.h"
#include "prov/provider_ctx.h"
#include "prov/provider_util.h"
#include "prov/providercommon.h"

#include "e_os.h"

#define ossl_min(a, b) ((a) < (b)) ? (a) : (b)

typedef enum {
    COUNTER = 0,
    FEEDBACK
} kbkdf_mode;

/* Our context structure. */
typedef struct {
    void *provctx;
    kbkdf_mode mode;
    EVP_MAC_CTX *ctx_init;

    /* Names are lowercased versions of those found in SP800-108. */
    unsigned char *ki;
    size_t ki_len;
    unsigned char *label;
    size_t label_len;
    unsigned char *context;
    size_t context_len;
    unsigned char *iv;
    size_t iv_len;
    int use_l;
    int use_separator;
} KBKDF;

/* Definitions needed for typechecking. */
static OSSL_FUNC_kdf_newctx_fn kbkdf_new;
static OSSL_FUNC_kdf_freectx_fn kbkdf_free;
static OSSL_FUNC_kdf_reset_fn kbkdf_reset;
static OSSL_FUNC_kdf_derive_fn kbkdf_derive;
static OSSL_FUNC_kdf_settable_ctx_params_fn kbkdf_settable_ctx_params;
static OSSL_FUNC_kdf_set_ctx_params_fn kbkdf_set_ctx_params;
static OSSL_FUNC_kdf_gettable_ctx_params_fn kbkdf_gettable_ctx_params;
static OSSL_FUNC_kdf_get_ctx_params_fn kbkdf_get_ctx_params;

/* Not all platforms have htobe32(). */
static uint32_t be32(uint32_t host)
{
    uint32_t big = 0;
    DECLARE_IS_ENDIAN;

    if (!IS_LITTLE_ENDIAN)
        return host;

    big |= (host & 0xff000000) >> 24;
    big |= (host & 0x00ff0000) >> 8;
    big |= (host & 0x0000ff00) << 8;
    big |= (host & 0x000000ff) << 24;
    return big;
}

static void init(KBKDF *ctx)
{
    ctx->use_l = 1;
    ctx->use_separator = 1;
}

static void *kbkdf_new(void *provctx)
{
    KBKDF *ctx;

    if (!ossl_prov_is_running())
        return NULL;

    ctx = OPENSSL_zalloc(sizeof(*ctx));
    if (ctx == NULL) {
        ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
        return NULL;
    }

    ctx->provctx = provctx;
    init(ctx);
    return ctx;
}

static void kbkdf_free(void *vctx)
{
    KBKDF *ctx = (KBKDF *)vctx;

    if (ctx != NULL) {
        kbkdf_reset(ctx);
        OPENSSL_free(ctx);
    }
}

static void kbkdf_reset(void *vctx)
{
    KBKDF *ctx = (KBKDF *)vctx;
    void *provctx = ctx->provctx;

    EVP_MAC_CTX_free(ctx->ctx_init);
    OPENSSL_clear_free(ctx->context, ctx->context_len);
    OPENSSL_clear_free(ctx->label, ctx->label_len);
    OPENSSL_clear_free(ctx->ki, ctx->ki_len);
    OPENSSL_clear_free(ctx->iv, ctx->iv_len);
    memset(ctx, 0, sizeof(*ctx));
    ctx->provctx = provctx;
    init(ctx);
}

/* SP800-108 section 5.1 or section 5.2 depending on mode. */
static int derive(EVP_MAC_CTX *ctx_init, kbkdf_mode mode, unsigned char *iv,
                  size_t iv_len, unsigned char *label, size_t label_len,
                  unsigned char *context, size_t context_len,
                  unsigned char *k_i, size_t h, uint32_t l, int has_separator,
                  unsigned char *ko, size_t ko_len)
{
    int ret = 0;
    EVP_MAC_CTX *ctx = NULL;
    size_t written = 0, to_write, k_i_len = iv_len;
    const unsigned char zero = 0;
    uint32_t counter, i;
    /*
     * From SP800-108:
     * The fixed input data is a concatenation of a Label,
     * a separation indicator 0x00, the Context, and L.
     * One or more of these fixed input data fields may be omitted.
     *
     * has_separator == 0 means that the separator is omitted.
     * Passing a value of l == 0 means that L is omitted.
     * The Context and L are omitted automatically if a NULL buffer is passed.
     */
    int has_l = (l != 0);

    /* Setup K(0) for feedback mode. */
    if (iv_len > 0)
        memcpy(k_i, iv, iv_len);

    for (counter = 1; written < ko_len; counter++) {
        i = be32(counter);

        ctx = EVP_MAC_CTX_dup(ctx_init);
        if (ctx == NULL)
            goto done;

        /* Perform feedback, if appropriate. */
        if (mode == FEEDBACK && !EVP_MAC_update(ctx, k_i, k_i_len))
            goto done;

        if (!EVP_MAC_update(ctx, (unsigned char *)&i, 4)
            || !EVP_MAC_update(ctx, label, label_len)
            || (has_separator && !EVP_MAC_update(ctx, &zero, 1))
            || !EVP_MAC_update(ctx, context, context_len)
            || (has_l && !EVP_MAC_update(ctx, (unsigned char *)&l, 4))
            || !EVP_MAC_final(ctx, k_i, NULL, h))
            goto done;

        to_write = ko_len - written;
        memcpy(ko + written, k_i, ossl_min(to_write, h));
        written += h;

        k_i_len = h;
        EVP_MAC_CTX_free(ctx);
        ctx = NULL;
    }

    ret = 1;
done:
    EVP_MAC_CTX_free(ctx);
    return ret;
}

static int kbkdf_derive(void *vctx, unsigned char *key, size_t keylen,
                        const OSSL_PARAM params[])
{
    KBKDF *ctx = (KBKDF *)vctx;
    int ret = 0;
    unsigned char *k_i = NULL;
    uint32_t l = 0;
    size_t h = 0;

    if (!ossl_prov_is_running() || !kbkdf_set_ctx_params(ctx, params))
        return 0;

    /* label, context, and iv are permitted to be empty.  Check everything
     * else. */
    if (ctx->ctx_init == NULL) {
        if (ctx->ki_len == 0 || ctx->ki == NULL) {
            ERR_raise(ERR_LIB_PROV, PROV_R_NO_KEY_SET);
            return 0;
        }
        /* Could either be missing MAC or missing message digest or missing
         * cipher - arbitrarily, I pick this one. */
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MAC);
        return 0;
    }

    /* Fail if the output length is zero */
    if (keylen == 0) {
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
        return 0;
    }

    h = EVP_MAC_CTX_get_mac_size(ctx->ctx_init);
    if (h == 0)
        goto done;
    if (ctx->iv_len != 0 && ctx->iv_len != h) {
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_SEED_LENGTH);
        goto done;
    }

    if (ctx->use_l != 0)
        l = be32(keylen * 8);

    k_i = OPENSSL_zalloc(h);
    if (k_i == NULL)
        goto done;

    ret = derive(ctx->ctx_init, ctx->mode, ctx->iv, ctx->iv_len, ctx->label,
                 ctx->label_len, ctx->context, ctx->context_len, k_i, h, l,
                 ctx->use_separator, key, keylen);
done:
    if (ret != 1)
        OPENSSL_cleanse(key, keylen);
    OPENSSL_clear_free(k_i, h);
    return ret;
}

static int kbkdf_set_buffer(unsigned char **out, size_t *out_len,
                            const OSSL_PARAM *p)
{
    if (p->data == NULL || p->data_size == 0)
        return 1;

    OPENSSL_clear_free(*out, *out_len);
    *out = NULL;
    return OSSL_PARAM_get_octet_string(p, (void **)out, 0, out_len);
}

static int kbkdf_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
    KBKDF *ctx = (KBKDF *)vctx;
    OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
    const OSSL_PARAM *p;

    if (params == NULL)
        return 1;

    if (!ossl_prov_macctx_load_from_params(&ctx->ctx_init, params, NULL,
                                           NULL, NULL, libctx))
        return 0;
    else if (ctx->ctx_init != NULL
             && !EVP_MAC_is_a(EVP_MAC_CTX_get0_mac(ctx->ctx_init),
                              OSSL_MAC_NAME_HMAC)
             && !EVP_MAC_is_a(EVP_MAC_CTX_get0_mac(ctx->ctx_init),
                              OSSL_MAC_NAME_CMAC)) {
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MAC);
        return 0;
    }

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_MODE);
    if (p != NULL
        && OPENSSL_strncasecmp("counter", p->data, p->data_size) == 0) {
        ctx->mode = COUNTER;
    } else if (p != NULL
               && OPENSSL_strncasecmp("feedback", p->data, p->data_size) == 0) {
        ctx->mode = FEEDBACK;
    } else if (p != NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MODE);
        return 0;
    }

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KEY);
    if (p != NULL && !kbkdf_set_buffer(&ctx->ki, &ctx->ki_len, p))
        return 0;

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT);
    if (p != NULL && !kbkdf_set_buffer(&ctx->label, &ctx->label_len, p))
        return 0;

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_INFO);
    if (p != NULL && !kbkdf_set_buffer(&ctx->context, &ctx->context_len, p))
        return 0;

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SEED);
    if (p != NULL && !kbkdf_set_buffer(&ctx->iv, &ctx->iv_len, p))
        return 0;

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KBKDF_USE_L);
    if (p != NULL && !OSSL_PARAM_get_int(p, &ctx->use_l))
        return 0;

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KBKDF_USE_SEPARATOR);
    if (p != NULL && !OSSL_PARAM_get_int(p, &ctx->use_separator))
        return 0;

    /* Set up digest context, if we can. */
    if (ctx->ctx_init != NULL && ctx->ki_len != 0
            && !EVP_MAC_init(ctx->ctx_init, ctx->ki, ctx->ki_len, NULL))
            return 0;
    return 1;
}

static const OSSL_PARAM *kbkdf_settable_ctx_params(ossl_unused void *ctx,
                                                   ossl_unused void *provctx)
{
    static const OSSL_PARAM known_settable_ctx_params[] = {
        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_INFO, NULL, 0),
        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_KEY, NULL, 0),
        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SEED, NULL, 0),
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0),
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_CIPHER, NULL, 0),
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_MAC, NULL, 0),
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_MODE, NULL, 0),
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
        OSSL_PARAM_int(OSSL_KDF_PARAM_KBKDF_USE_L, NULL),
        OSSL_PARAM_int(OSSL_KDF_PARAM_KBKDF_USE_SEPARATOR, NULL),
        OSSL_PARAM_END,
    };
    return known_settable_ctx_params;
}

static int kbkdf_get_ctx_params(void *vctx, OSSL_PARAM params[])
{
    OSSL_PARAM *p;

    p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE);
    if (p == NULL)
        return -2;

    /* KBKDF can produce results as large as you like. */
    return OSSL_PARAM_set_size_t(p, SIZE_MAX);
}

static const OSSL_PARAM *kbkdf_gettable_ctx_params(ossl_unused void *ctx,
                                                   ossl_unused void *provctx)
{
    static const OSSL_PARAM known_gettable_ctx_params[] =
        { OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL), OSSL_PARAM_END };
    return known_gettable_ctx_params;
}

const OSSL_DISPATCH ossl_kdf_kbkdf_functions[] = {
    { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kbkdf_new },
    { OSSL_FUNC_KDF_FREECTX, (void(*)(void))kbkdf_free },
    { OSSL_FUNC_KDF_RESET, (void(*)(void))kbkdf_reset },
    { OSSL_FUNC_KDF_DERIVE, (void(*)(void))kbkdf_derive },
    { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
      (void(*)(void))kbkdf_settable_ctx_params },
    { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kbkdf_set_ctx_params },
    { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
      (void(*)(void))kbkdf_gettable_ctx_params },
    { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kbkdf_get_ctx_params },
    { 0, NULL },
};

Coverage Report

Created: 2025-06-13 06:58

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 2019-2022 The OpenSSL Project Authors. All Rights Reserved.
3		* Copyright 2019 Red Hat, Inc.
4		*
5		* Licensed under the Apache License 2.0 (the "License"). You may not use
6		* this file except in compliance with the License. You can obtain a copy
7		* in the file LICENSE in the source distribution or at
8		* https://www.openssl.org/source/license.html
9		*/
10
11		/*
12		* This implements https://csrc.nist.gov/publications/detail/sp/800-108/final
13		* section 5.1 ("counter mode") and section 5.2 ("feedback mode") in both HMAC
14		* and CMAC. That document does not name the KDFs it defines; the name is
15		* derived from
16		* https://csrc.nist.gov/Projects/Cryptographic-Algorithm-Validation-Program/Key-Derivation
17		*
18		* Note that section 5.3 ("double-pipeline mode") is not implemented, though
19		* it would be possible to do so in the future.
20		*
21		* These versions all assume the counter is used. It would be relatively
22		* straightforward to expose a configuration handle should the need arise.
23		*
24		* Variable names attempt to match those of SP800-108.
25		*/
26
27		#include <stdarg.h>
28		#include <stdlib.h>
29		#include <string.h>
30
31		#include <openssl/core_names.h>
32		#include <openssl/evp.h>
33		#include <openssl/hmac.h>
34		#include <openssl/kdf.h>
35		#include <openssl/params.h>
36		#include <openssl/proverr.h>
37
38		#include "internal/cryptlib.h"
39		#include "crypto/evp.h"
40		#include "internal/numbers.h"
41		#include "internal/endian.h"
42		#include "prov/implementations.h"
43		#include "prov/provider_ctx.h"
44		#include "prov/provider_util.h"
45		#include "prov/providercommon.h"
46
47		#include "e_os.h"
48
49	19	#define ossl_min(a, b) ((a) < (b)) ? (a) : (b)
50
51		typedef enum {
52		COUNTER = 0,
53		FEEDBACK
54		} kbkdf_mode;
55
56		/* Our context structure. */
57		typedef struct {
58		void *provctx;
59		kbkdf_mode mode;
60		EVP_MAC_CTX *ctx_init;
61
62		/* Names are lowercased versions of those found in SP800-108. */
63		unsigned char *ki;
64		size_t ki_len;
65		unsigned char *label;
66		size_t label_len;
67		unsigned char *context;
68		size_t context_len;
69		unsigned char *iv;
70		size_t iv_len;
71		int use_l;
72		int use_separator;
73		} KBKDF;
74
75		/* Definitions needed for typechecking. */
76		static OSSL_FUNC_kdf_newctx_fn kbkdf_new;
77		static OSSL_FUNC_kdf_freectx_fn kbkdf_free;
78		static OSSL_FUNC_kdf_reset_fn kbkdf_reset;
79		static OSSL_FUNC_kdf_derive_fn kbkdf_derive;
80		static OSSL_FUNC_kdf_settable_ctx_params_fn kbkdf_settable_ctx_params;
81		static OSSL_FUNC_kdf_set_ctx_params_fn kbkdf_set_ctx_params;
82		static OSSL_FUNC_kdf_gettable_ctx_params_fn kbkdf_gettable_ctx_params;
83		static OSSL_FUNC_kdf_get_ctx_params_fn kbkdf_get_ctx_params;
84
85		/* Not all platforms have htobe32(). */
86		static uint32_t be32(uint32_t host)
87	24	{
88	24	uint32_t big = 0;
89	24	DECLARE_IS_ENDIAN;
90
91	24	if (!IS_LITTLE_ENDIAN)
92	0	return host;
93
94	24	big \|= (host & 0xff000000) >> 24;
95	24	big \|= (host & 0x00ff0000) >> 8;
96	24	big \|= (host & 0x0000ff00) << 8;
97	24	big \|= (host & 0x000000ff) << 24;
98	24	return big;
99	24	}
100
101		static void init(KBKDF *ctx)
102	180	{
103	180	ctx->use_l = 1;
104	180	ctx->use_separator = 1;
105	180	}
106
107		static void kbkdf_new(void provctx)
108	90	{
109	90	KBKDF *ctx;
110
111	90	if (!ossl_prov_is_running())
112	0	return NULL;
113
114	90	ctx = OPENSSL_zalloc(sizeof(*ctx));
115	90	if (ctx == NULL) {
116	0	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
117	0	return NULL;
118	0	}
119
120	90	ctx->provctx = provctx;
121	90	init(ctx);
122	90	return ctx;
123	90	}
124
125		static void kbkdf_free(void *vctx)
126	90	{
127	90	KBKDF ctx = (KBKDF )vctx;
128
129	90	if (ctx != NULL) {
130	90	kbkdf_reset(ctx);
131	90	OPENSSL_free(ctx);
132	90	}
133	90	}
134
135		static void kbkdf_reset(void *vctx)
136	90	{
137	90	KBKDF ctx = (KBKDF )vctx;
138	90	void *provctx = ctx->provctx;
139
140	90	EVP_MAC_CTX_free(ctx->ctx_init);
141	90	OPENSSL_clear_free(ctx->context, ctx->context_len);
142	90	OPENSSL_clear_free(ctx->label, ctx->label_len);
143	90	OPENSSL_clear_free(ctx->ki, ctx->ki_len);
144	90	OPENSSL_clear_free(ctx->iv, ctx->iv_len);
145	90	memset(ctx, 0, sizeof(*ctx));
146	90	ctx->provctx = provctx;
147	90	init(ctx);
148	90	}
149
150		/* SP800-108 section 5.1 or section 5.2 depending on mode. */
151		static int derive(EVP_MAC_CTX ctx_init, kbkdf_mode mode, unsigned char iv,
152		size_t iv_len, unsigned char *label, size_t label_len,
153		unsigned char *context, size_t context_len,
154		unsigned char *k_i, size_t h, uint32_t l, int has_separator,
155		unsigned char *ko, size_t ko_len)
156	13	{
157	13	int ret = 0;
158	13	EVP_MAC_CTX *ctx = NULL;
159	13	size_t written = 0, to_write, k_i_len = iv_len;
160	13	const unsigned char zero = 0;
161	13	uint32_t counter, i;
162		/*
163		* From SP800-108:
164		* The fixed input data is a concatenation of a Label,
165		* a separation indicator 0x00, the Context, and L.
166		* One or more of these fixed input data fields may be omitted.
167		*
168		* has_separator == 0 means that the separator is omitted.
169		* Passing a value of l == 0 means that L is omitted.
170		* The Context and L are omitted automatically if a NULL buffer is passed.
171		*/
172	13	int has_l = (l != 0);
173
174		/* Setup K(0) for feedback mode. */
175	13	if (iv_len > 0)
176	4	memcpy(k_i, iv, iv_len);
177
178	32	for (counter = 1; written < ko_len; counter++) {
179	19	i = be32(counter);
180
181	19	ctx = EVP_MAC_CTX_dup(ctx_init);
182	19	if (ctx == NULL)
183	0	goto done;
184
185		/* Perform feedback, if appropriate. */
186	19	if (mode == FEEDBACK && !EVP_MAC_update(ctx, k_i, k_i_len))
187	0	goto done;
188
189	19	if (!EVP_MAC_update(ctx, (unsigned char *)&i, 4)
190	19	\|\| !EVP_MAC_update(ctx, label, label_len)
191	19	\|\| (has_separator && !EVP_MAC_update(ctx, &zero, 1))
192	19	\|\| !EVP_MAC_update(ctx, context, context_len)
193	19	\|\| (has_l && !EVP_MAC_update(ctx, (unsigned char *)&l, 4))
194	19	\|\| !EVP_MAC_final(ctx, k_i, NULL, h))
195	0	goto done;
196
197	19	to_write = ko_len - written;
198	19	memcpy(ko + written, k_i, ossl_min(to_write, h));
199	19	written += h;
200
201	19	k_i_len = h;
202	19	EVP_MAC_CTX_free(ctx);
203	19	ctx = NULL;
204	19	}
205
206	13	ret = 1;
207	13	done:
208	13	EVP_MAC_CTX_free(ctx);
209	13	return ret;
210	13	}
211
212		static int kbkdf_derive(void vctx, unsigned char key, size_t keylen,
213		const OSSL_PARAM params[])
214	0	{
215	0	KBKDF ctx = (KBKDF )vctx;
216	0	int ret = 0;
217	0	unsigned char *k_i = NULL;
218	0	uint32_t l = 0;
219	0	size_t h = 0;
220
221	0	if (!ossl_prov_is_running() \|\| !kbkdf_set_ctx_params(ctx, params))
222	0	return 0;
223
224		/* label, context, and iv are permitted to be empty. Check everything
225		* else. */
226	0	if (ctx->ctx_init == NULL) {
227	0	if (ctx->ki_len == 0 \|\| ctx->ki == NULL) {
228	0	ERR_raise(ERR_LIB_PROV, PROV_R_NO_KEY_SET);
229	0	return 0;
230	0	}
231		/* Could either be missing MAC or missing message digest or missing
232		* cipher - arbitrarily, I pick this one. */
233	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MAC);
234	0	return 0;
235	0	}
236
237		/* Fail if the output length is zero */
238	0	if (keylen == 0) {
239	0	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
240	0	return 0;
241	0	}
242
243	0	h = EVP_MAC_CTX_get_mac_size(ctx->ctx_init);
244	0	if (h == 0)
245	0	goto done;
246	0	if (ctx->iv_len != 0 && ctx->iv_len != h) {
247	0	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_SEED_LENGTH);
248	0	goto done;
249	0	}
250
251	0	if (ctx->use_l != 0)
252	0	l = be32(keylen * 8);
253
254	0	k_i = OPENSSL_zalloc(h);
255	0	if (k_i == NULL)
256	0	goto done;
257
258	0	ret = derive(ctx->ctx_init, ctx->mode, ctx->iv, ctx->iv_len, ctx->label,
259	0	ctx->label_len, ctx->context, ctx->context_len, k_i, h, l,
260	0	ctx->use_separator, key, keylen);
261	0	done:
262	0	if (ret != 1)
263	0	OPENSSL_cleanse(key, keylen);
264	0	OPENSSL_clear_free(k_i, h);
265	0	return ret;
266	0	}
267
268		static int kbkdf_set_buffer(unsigned char *out, size_t out_len,
269		const OSSL_PARAM *p)
270	0	{
271	0	if (p->data == NULL \|\| p->data_size == 0)
272	0	return 1;
273
274	0	OPENSSL_clear_free(out, out_len);
275	0	*out = NULL;
276	0	return OSSL_PARAM_get_octet_string(p, (void **)out, 0, out_len);
277	0	}
278
279		static int kbkdf_set_ctx_params(void *vctx, const OSSL_PARAM params[])
280		{
281		KBKDF ctx = (KBKDF )vctx;
282		OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
283		const OSSL_PARAM *p;
284
285		if (params == NULL)
286		return 1;
287
288		if (!ossl_prov_macctx_load_from_params(&ctx->ctx_init, params, NULL,
289		NULL, NULL, libctx))
290		return 0;
291		else if (ctx->ctx_init != NULL
292		&& !EVP_MAC_is_a(EVP_MAC_CTX_get0_mac(ctx->ctx_init),
293		OSSL_MAC_NAME_HMAC)
294		&& !EVP_MAC_is_a(EVP_MAC_CTX_get0_mac(ctx->ctx_init),
295		OSSL_MAC_NAME_CMAC)) {
296		ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MAC);
297		return 0;
298		}
299
300		p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_MODE);
301		if (p != NULL
302		&& OPENSSL_strncasecmp("counter", p->data, p->data_size) == 0) {
303		ctx->mode = COUNTER;
304		} else if (p != NULL
305		&& OPENSSL_strncasecmp("feedback", p->data, p->data_size) == 0) {
306		ctx->mode = FEEDBACK;
307		} else if (p != NULL) {
308		ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MODE);
309		return 0;
310		}
311
312		p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KEY);
313		if (p != NULL && !kbkdf_set_buffer(&ctx->ki, &ctx->ki_len, p))
314		return 0;
315
316		p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT);
317		if (p != NULL && !kbkdf_set_buffer(&ctx->label, &ctx->label_len, p))
318		return 0;
319
320		p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_INFO);
321		if (p != NULL && !kbkdf_set_buffer(&ctx->context, &ctx->context_len, p))
322		return 0;
323
324		p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SEED);
325		if (p != NULL && !kbkdf_set_buffer(&ctx->iv, &ctx->iv_len, p))
326		return 0;
327
328		p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KBKDF_USE_L);
329		if (p != NULL && !OSSL_PARAM_get_int(p, &ctx->use_l))
330		return 0;
331
332		p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KBKDF_USE_SEPARATOR);
333		if (p != NULL && !OSSL_PARAM_get_int(p, &ctx->use_separator))
334		return 0;
335
336		/* Set up digest context, if we can. */
337		if (ctx->ctx_init != NULL && ctx->ki_len != 0
338		&& !EVP_MAC_init(ctx->ctx_init, ctx->ki, ctx->ki_len, NULL))
339		return 0;
340		return 1;
341		}
342
343		static const OSSL_PARAM kbkdf_settable_ctx_params(ossl_unused void ctx,
344		ossl_unused void *provctx)
345	90	{
346	90	static const OSSL_PARAM known_settable_ctx_params[] = {
347	90	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_INFO, NULL, 0),
348	90	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
349	90	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_KEY, NULL, 0),
350	90	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SEED, NULL, 0),
351	90	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0),
352	90	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_CIPHER, NULL, 0),
353	90	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_MAC, NULL, 0),
354	90	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_MODE, NULL, 0),
355	90	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
356	90	OSSL_PARAM_int(OSSL_KDF_PARAM_KBKDF_USE_L, NULL),
357	90	OSSL_PARAM_int(OSSL_KDF_PARAM_KBKDF_USE_SEPARATOR, NULL),
358	90	OSSL_PARAM_END,
359	90	};
360	90	return known_settable_ctx_params;
361	90	}
362
363		static int kbkdf_get_ctx_params(void *vctx, OSSL_PARAM params[])
364	0	{
365	0	OSSL_PARAM *p;
366
367	0	p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE);
368	0	if (p == NULL)
369	0	return -2;
370
371		/* KBKDF can produce results as large as you like. */
372	0	return OSSL_PARAM_set_size_t(p, SIZE_MAX);
373	0	}
374
375		static const OSSL_PARAM kbkdf_gettable_ctx_params(ossl_unused void ctx,
376		ossl_unused void *provctx)
377	0	{
378	0	static const OSSL_PARAM known_gettable_ctx_params[] =
379	0	{ OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL), OSSL_PARAM_END };
380	0	return known_gettable_ctx_params;
381	0	}
382
383		const OSSL_DISPATCH ossl_kdf_kbkdf_functions[] = {
384		{ OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kbkdf_new },
385		{ OSSL_FUNC_KDF_FREECTX, (void(*)(void))kbkdf_free },
386		{ OSSL_FUNC_KDF_RESET, (void(*)(void))kbkdf_reset },
387		{ OSSL_FUNC_KDF_DERIVE, (void(*)(void))kbkdf_derive },
388		{ OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
389		(void(*)(void))kbkdf_settable_ctx_params },
390		{ OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kbkdf_set_ctx_params },
391		{ OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
392		(void(*)(void))kbkdf_gettable_ctx_params },
393		{ OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kbkdf_get_ctx_params },
394		{ 0, NULL },
395		};