[thirdparty/openssl.git] / providers / implementations / kdfs / pbkdf2.c

/*
 * Copyright 2018-2019 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 <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <openssl/hmac.h>
#include <openssl/evp.h>
#include <openssl/kdf.h>
#include <openssl/core_names.h>
#include "internal/cryptlib.h"
#include "internal/numbers.h"
#include "crypto/evp.h"
#include "prov/provider_ctx.h"
#include "prov/providercommonerr.h"
#include "prov/implementations.h"
#include "prov/provider_util.h"
#include "pbkdf2.h"

/* Constants specified in SP800-132 */
#define KDF_PBKDF2_MIN_KEY_LEN_BITS  112
#define KDF_PBKDF2_MAX_KEY_LEN_DIGEST_RATIO 0xFFFFFFFF
#define KDF_PBKDF2_MIN_ITERATIONS 1000
#define KDF_PBKDF2_MIN_SALT_LEN   (128 / 8)

static OSSL_OP_kdf_newctx_fn kdf_pbkdf2_new;
static OSSL_OP_kdf_freectx_fn kdf_pbkdf2_free;
static OSSL_OP_kdf_reset_fn kdf_pbkdf2_reset;
static OSSL_OP_kdf_derive_fn kdf_pbkdf2_derive;
static OSSL_OP_kdf_settable_ctx_params_fn kdf_pbkdf2_settable_ctx_params;
static OSSL_OP_kdf_set_ctx_params_fn kdf_pbkdf2_set_ctx_params;

static int  pbkdf2_derive(const char *pass, size_t passlen,
                          const unsigned char *salt, int saltlen, uint64_t iter,
                          const EVP_MD *digest, unsigned char *key,
                          size_t keylen, int extra_checks);

typedef struct {
    void *provctx;
    unsigned char *pass;
    size_t pass_len;
    unsigned char *salt;
    size_t salt_len;
    uint64_t iter;
    PROV_DIGEST digest;
    int lower_bound_checks;
} KDF_PBKDF2;

static void kdf_pbkdf2_init(KDF_PBKDF2 *ctx);

static void *kdf_pbkdf2_new(void *provctx)
{
    KDF_PBKDF2 *ctx;

    ctx = OPENSSL_zalloc(sizeof(*ctx));
    if (ctx == NULL) {
        ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
        return NULL;
    }
    ctx->provctx = provctx;
    kdf_pbkdf2_init(ctx);
    return ctx;
}

static void kdf_pbkdf2_cleanup(KDF_PBKDF2 *ctx)
{
    ossl_prov_digest_reset(&ctx->digest);
    OPENSSL_free(ctx->salt);
    OPENSSL_clear_free(ctx->pass, ctx->pass_len);
    memset(ctx, 0, sizeof(*ctx));
}

static void kdf_pbkdf2_free(void *vctx)
{
    KDF_PBKDF2 *ctx = (KDF_PBKDF2 *)vctx;

    if (ctx != NULL) {
        kdf_pbkdf2_cleanup(ctx);
        OPENSSL_free(ctx);
    }
}

static void kdf_pbkdf2_reset(void *vctx)
{
    KDF_PBKDF2 *ctx = (KDF_PBKDF2 *)vctx;

    kdf_pbkdf2_cleanup(ctx);
    kdf_pbkdf2_init(ctx);
}

static void kdf_pbkdf2_init(KDF_PBKDF2 *ctx)
{
    OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
    OPENSSL_CTX *provctx = PROV_LIBRARY_CONTEXT_OF(ctx->provctx);

    params[0] = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
                                                 SN_sha1, 0);
    if (!ossl_prov_digest_load_from_params(&ctx->digest, params, provctx))
        /* This is an error, but there is no way to indicate such directly */
        ossl_prov_digest_reset(&ctx->digest);
    ctx->iter = PKCS5_DEFAULT_ITER;
    ctx->lower_bound_checks = kdf_pbkdf2_default_checks;
}

static int pbkdf2_set_membuf(unsigned char **buffer, size_t *buflen,
                             const OSSL_PARAM *p)
{
    OPENSSL_clear_free(*buffer, *buflen);
    if (p->data_size == 0) {
        if ((*buffer = OPENSSL_malloc(1)) == NULL) {
            ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
            return 0;
        }
    } else if (p->data != NULL) {
        *buffer = NULL;
        if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
            return 0;
    }
    return 1;
}

static int kdf_pbkdf2_derive(void *vctx, unsigned char *key,
                             size_t keylen)
{
    KDF_PBKDF2 *ctx = (KDF_PBKDF2 *)vctx;
    const EVP_MD *md = ossl_prov_digest_md(&ctx->digest);

    if (ctx->pass == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
        return 0;
    }

    if (ctx->salt == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
        return 0;
    }

    return pbkdf2_derive((char *)ctx->pass, ctx->pass_len,
                         ctx->salt, ctx->salt_len, ctx->iter,
                         md, key, keylen, ctx->lower_bound_checks);
}

static int kdf_pbkdf2_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
    const OSSL_PARAM *p;
    KDF_PBKDF2 *ctx = vctx;
    OPENSSL_CTX *provctx = PROV_LIBRARY_CONTEXT_OF(ctx->provctx);
    int pkcs5;
    uint64_t iter, min_iter;

    if (!ossl_prov_digest_load_from_params(&ctx->digest, params, provctx))
        return 0;

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PKCS5)) != NULL) {
        if (!OSSL_PARAM_get_int(p, &pkcs5))
            return 0;
        ctx->lower_bound_checks = pkcs5 == 0;
    }

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL)
        if (!pbkdf2_set_membuf(&ctx->pass, &ctx->pass_len, p))
            return 0;

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL) {
        if (ctx->lower_bound_checks != 0
            && p->data_size < KDF_PBKDF2_MIN_SALT_LEN) {
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_SALT_LENGTH);
            return 0;
        }
        if (!pbkdf2_set_membuf(&ctx->salt, &ctx->salt_len,p))
            return 0;
    }

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_ITER)) != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &iter))
            return 0;
        min_iter = ctx->lower_bound_checks != 0 ? KDF_PBKDF2_MIN_ITERATIONS : 1;
        if (iter < min_iter) {
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_ITERATION_COUNT);
            return 0;
        }
        ctx->iter = iter;
    }
    return 1;
}

static const OSSL_PARAM *kdf_pbkdf2_settable_ctx_params(void)
{
    static const OSSL_PARAM known_settable_ctx_params[] = {
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0),
        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD, NULL, 0),
        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
        OSSL_PARAM_uint64(OSSL_KDF_PARAM_ITER, NULL),
        OSSL_PARAM_int(OSSL_KDF_PARAM_PKCS5, NULL),
        OSSL_PARAM_END
    };
    return known_settable_ctx_params;
}

static int kdf_pbkdf2_get_ctx_params(void *vctx, OSSL_PARAM params[])
{
    OSSL_PARAM *p;

    if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
        return OSSL_PARAM_set_size_t(p, SIZE_MAX);
    return -2;
}

static const OSSL_PARAM *kdf_pbkdf2_gettable_ctx_params(void)
{
    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 kdf_pbkdf2_functions[] = {
    { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_pbkdf2_new },
    { OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_pbkdf2_free },
    { OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_pbkdf2_reset },
    { OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_pbkdf2_derive },
    { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
      (void(*)(void))kdf_pbkdf2_settable_ctx_params },
    { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_pbkdf2_set_ctx_params },
    { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
      (void(*)(void))kdf_pbkdf2_gettable_ctx_params },
    { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_pbkdf2_get_ctx_params },
    { 0, NULL }
};

/*
 * This is an implementation of PKCS#5 v2.0 password based encryption key
 * derivation function PBKDF2. SHA1 version verified against test vectors
 * posted by Peter Gutmann to the PKCS-TNG mailing list.
 *
 * The constraints specified by SP800-132 have been added i.e.
 *  - Check the range of the key length.
 *  - Minimum iteration count of 1000.
 *  - Randomly-generated portion of the salt shall be at least 128 bits.
 */
static int pbkdf2_derive(const char *pass, size_t passlen,
                         const unsigned char *salt, int saltlen, uint64_t iter,
                         const EVP_MD *digest, unsigned char *key,
                         size_t keylen, int lower_bound_checks)
{
    int ret = 0;
    unsigned char digtmp[EVP_MAX_MD_SIZE], *p, itmp[4];
    int cplen, k, tkeylen, mdlen;
    uint64_t j;
    unsigned long i = 1;
    HMAC_CTX *hctx_tpl = NULL, *hctx = NULL;

    mdlen = EVP_MD_size(digest);
    if (mdlen <= 0)
        return 0;

    /*
     * This check should always be done because keylen / mdlen >= (2^32 - 1)
     * results in an overflow of the loop counter 'i'.
     */
    if ((keylen / mdlen) >= KDF_PBKDF2_MAX_KEY_LEN_DIGEST_RATIO) {
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LEN);
        return 0;
    }

    if (lower_bound_checks) {
        if ((keylen * 8) < KDF_PBKDF2_MIN_KEY_LEN_BITS) {
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LEN);
            return 0;
        }
        if (saltlen < KDF_PBKDF2_MIN_SALT_LEN) {
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_SALT_LENGTH);
            return 0;
        }
        if (iter < KDF_PBKDF2_MIN_ITERATIONS) {
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_ITERATION_COUNT);
            return 0;
        }
    }

    hctx_tpl = HMAC_CTX_new();
    if (hctx_tpl == NULL)
        return 0;
    p = key;
    tkeylen = keylen;
    if (!HMAC_Init_ex(hctx_tpl, pass, passlen, digest, NULL))
        goto err;
    hctx = HMAC_CTX_new();
    if (hctx == NULL)
        goto err;
    while (tkeylen) {
        if (tkeylen > mdlen)
            cplen = mdlen;
        else
            cplen = tkeylen;
        /*
         * We are unlikely to ever use more than 256 blocks (5120 bits!) but
         * just in case...
         */
        itmp[0] = (unsigned char)((i >> 24) & 0xff);
        itmp[1] = (unsigned char)((i >> 16) & 0xff);
        itmp[2] = (unsigned char)((i >> 8) & 0xff);
        itmp[3] = (unsigned char)(i & 0xff);
        if (!HMAC_CTX_copy(hctx, hctx_tpl))
            goto err;
        if (!HMAC_Update(hctx, salt, saltlen)
                || !HMAC_Update(hctx, itmp, 4)
                || !HMAC_Final(hctx, digtmp, NULL))
            goto err;
        memcpy(p, digtmp, cplen);
        for (j = 1; j < iter; j++) {
            if (!HMAC_CTX_copy(hctx, hctx_tpl))
                goto err;
            if (!HMAC_Update(hctx, digtmp, mdlen)
                    || !HMAC_Final(hctx, digtmp, NULL))
                goto err;
            for (k = 0; k < cplen; k++)
                p[k] ^= digtmp[k];
        }
        tkeylen -= cplen;
        i++;
        p += cplen;
    }
    ret = 1;

err:
    HMAC_CTX_free(hctx);
    HMAC_CTX_free(hctx_tpl);
    return ret;
}
Commit	Line	Data
5a285add	1	/*
f0efeea2	2	* Copyright 2018-2019 The OpenSSL Project Authors. All Rights Reserved.
5a285add DM	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
dbde4726 P	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
5a285add DM	16	#include <stdlib.h>
	17	#include <stdarg.h>
	18	#include <string.h>
	19	#include <openssl/hmac.h>
	20	#include <openssl/evp.h>
	21	#include <openssl/kdf.h>
e3405a4a	22	#include <openssl/core_names.h>
5a285add	23	#include "internal/cryptlib.h"
e3405a4a	24	#include "internal/numbers.h"
25f2138b	25	#include "crypto/evp.h"
ddd21319 RL	26	#include "prov/provider_ctx.h"
ddd21319 RL	27	#include "prov/providercommonerr.h"
af3e7e1b	28	#include "prov/implementations.h"
ddd21319	29	#include "prov/provider_util.h"
dec95d75	30	#include "pbkdf2.h"
5a285add	31
f0efeea2 SL	32	/* Constants specified in SP800-132 */
	33	#define KDF_PBKDF2_MIN_KEY_LEN_BITS 112
	34	#define KDF_PBKDF2_MAX_KEY_LEN_DIGEST_RATIO 0xFFFFFFFF
	35	#define KDF_PBKDF2_MIN_ITERATIONS 1000
	36	#define KDF_PBKDF2_MIN_SALT_LEN (128 / 8)
f0efeea2	37
e3405a4a P	38	static OSSL_OP_kdf_newctx_fn kdf_pbkdf2_new;
	39	static OSSL_OP_kdf_freectx_fn kdf_pbkdf2_free;
	40	static OSSL_OP_kdf_reset_fn kdf_pbkdf2_reset;
	41	static OSSL_OP_kdf_derive_fn kdf_pbkdf2_derive;
	42	static OSSL_OP_kdf_settable_ctx_params_fn kdf_pbkdf2_settable_ctx_params;
	43	static OSSL_OP_kdf_set_ctx_params_fn kdf_pbkdf2_set_ctx_params;
	44
f0efeea2	45	static int pbkdf2_derive(const char *pass, size_t passlen,
e3405a4a	46	const unsigned char *salt, int saltlen, uint64_t iter,
f0efeea2 SL	47	const EVP_MD digest, unsigned char key,
f0efeea2 SL	48	size_t keylen, int extra_checks);
5a285add	49
e3405a4a P	50	typedef struct {
e3405a4a P	51	void *provctx;
5a285add DM	52	unsigned char *pass;
	53	size_t pass_len;
	54	unsigned char *salt;
	55	size_t salt_len;
e3405a4a	56	uint64_t iter;
e957226a	57	PROV_DIGEST digest;
f0efeea2	58	int lower_bound_checks;
e3405a4a	59	} KDF_PBKDF2;
5a285add	60
e3405a4a P	61	static void kdf_pbkdf2_init(KDF_PBKDF2 *ctx);
	62
	63	static void kdf_pbkdf2_new(void provctx)
5a285add	64	{
e3405a4a	65	KDF_PBKDF2 *ctx;
5a285add	66
e3405a4a P	67	ctx = OPENSSL_zalloc(sizeof(*ctx));
	68	if (ctx == NULL) {
	69	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
5a285add DM	70	return NULL;
5a285add DM	71	}
e3405a4a P	72	ctx->provctx = provctx;
	73	kdf_pbkdf2_init(ctx);
	74	return ctx;
5a285add DM	75	}
5a285add DM	76
b1f15129 RL	77	static void kdf_pbkdf2_cleanup(KDF_PBKDF2 *ctx)
b1f15129 RL	78	{
e957226a	79	ossl_prov_digest_reset(&ctx->digest);
b1f15129 RL	80	OPENSSL_free(ctx->salt);
	81	OPENSSL_clear_free(ctx->pass, ctx->pass_len);
	82	memset(ctx, 0, sizeof(*ctx));
	83	}
	84
e3405a4a	85	static void kdf_pbkdf2_free(void *vctx)
5a285add	86	{
e3405a4a P	87	KDF_PBKDF2 ctx = (KDF_PBKDF2 )vctx;
e3405a4a P	88
3c659415 P	89	if (ctx != NULL) {
	90	kdf_pbkdf2_cleanup(ctx);
	91	OPENSSL_free(ctx);
	92	}
5a285add DM	93	}
5a285add DM	94
e3405a4a	95	static void kdf_pbkdf2_reset(void *vctx)
5a285add	96	{
e3405a4a P	97	KDF_PBKDF2 ctx = (KDF_PBKDF2 )vctx;
e3405a4a P	98
b1f15129	99	kdf_pbkdf2_cleanup(ctx);
e3405a4a	100	kdf_pbkdf2_init(ctx);
5a285add DM	101	}
5a285add DM	102
e3405a4a	103	static void kdf_pbkdf2_init(KDF_PBKDF2 *ctx)
5a285add	104	{
e957226a P	105	OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
	106	OPENSSL_CTX *provctx = PROV_LIBRARY_CONTEXT_OF(ctx->provctx);
	107
	108	params[0] = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
	109	SN_sha1, 0);
d111712f P	110	if (!ossl_prov_digest_load_from_params(&ctx->digest, params, provctx))
	111	/* This is an error, but there is no way to indicate such directly */
	112	ossl_prov_digest_reset(&ctx->digest);
e3405a4a	113	ctx->iter = PKCS5_DEFAULT_ITER;
dec95d75	114	ctx->lower_bound_checks = kdf_pbkdf2_default_checks;
5a285add DM	115	}
	116
	117	static int pbkdf2_set_membuf(unsigned char *buffer, size_t buflen,
e3405a4a	118	const OSSL_PARAM *p)
5a285add	119	{
5a285add	120	OPENSSL_clear_free(buffer, buflen);
e3405a4a P	121	if (p->data_size == 0) {
	122	if ((*buffer = OPENSSL_malloc(1)) == NULL) {
	123	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
	124	return 0;
	125	}
	126	} else if (p->data != NULL) {
	127	*buffer = NULL;
	128	if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
	129	return 0;
	130	}
	131	return 1;
	132	}
	133
	134	static int kdf_pbkdf2_derive(void vctx, unsigned char key,
	135	size_t keylen)
	136	{
	137	KDF_PBKDF2 ctx = (KDF_PBKDF2 )vctx;
e957226a	138	const EVP_MD *md = ossl_prov_digest_md(&ctx->digest);
5a285add	139
e3405a4a P	140	if (ctx->pass == NULL) {
	141	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
	142	return 0;
5a285add	143	}
e3405a4a P	144
	145	if (ctx->salt == NULL) {
	146	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
5a285add DM	147	return 0;
	148	}
	149
e3405a4a P	150	return pbkdf2_derive((char *)ctx->pass, ctx->pass_len,
e3405a4a P	151	ctx->salt, ctx->salt_len, ctx->iter,
e957226a	152	md, key, keylen, ctx->lower_bound_checks);
5a285add DM	153	}
5a285add DM	154
e3405a4a	155	static int kdf_pbkdf2_set_ctx_params(void *vctx, const OSSL_PARAM params[])
5a285add	156	{
e3405a4a P	157	const OSSL_PARAM *p;
e3405a4a P	158	KDF_PBKDF2 *ctx = vctx;
e957226a	159	OPENSSL_CTX *provctx = PROV_LIBRARY_CONTEXT_OF(ctx->provctx);
e3405a4a P	160	int pkcs5;
e3405a4a P	161	uint64_t iter, min_iter;
e3405a4a	162
e957226a P	163	if (!ossl_prov_digest_load_from_params(&ctx->digest, params, provctx))
e957226a P	164	return 0;
5a285add	165
e3405a4a P	166	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PKCS5)) != NULL) {
	167	if (!OSSL_PARAM_get_int(p, &pkcs5))
	168	return 0;
	169	ctx->lower_bound_checks = pkcs5 == 0;
5a285add DM	170	}
5a285add DM	171
e3405a4a P	172	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL)
	173	if (!pbkdf2_set_membuf(&ctx->pass, &ctx->pass_len, p))
	174	return 0;
5a285add	175
e3405a4a P	176	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL) {
	177	if (ctx->lower_bound_checks != 0
	178	&& p->data_size < KDF_PBKDF2_MIN_SALT_LEN) {
	179	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_SALT_LENGTH);
	180	return 0;
	181	}
	182	if (!pbkdf2_set_membuf(&ctx->salt, &ctx->salt_len,p))
	183	return 0;
	184	}
5a285add	185
e3405a4a P	186	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_ITER)) != NULL) {
	187	if (!OSSL_PARAM_get_uint64(p, &iter))
	188	return 0;
	189	min_iter = ctx->lower_bound_checks != 0 ? KDF_PBKDF2_MIN_ITERATIONS : 1;
	190	if (iter < min_iter) {
	191	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_ITERATION_COUNT);
	192	return 0;
	193	}
	194	ctx->iter = iter;
	195	}
	196	return 1;
	197	}
5a285add	198
e3405a4a P	199	static const OSSL_PARAM *kdf_pbkdf2_settable_ctx_params(void)
	200	{
	201	static const OSSL_PARAM known_settable_ctx_params[] = {
	202	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
	203	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0),
	204	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD, NULL, 0),
	205	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
	206	OSSL_PARAM_uint64(OSSL_KDF_PARAM_ITER, NULL),
	207	OSSL_PARAM_int(OSSL_KDF_PARAM_PKCS5, NULL),
	208	OSSL_PARAM_END
	209	};
	210	return known_settable_ctx_params;
	211	}
5a285add	212
e3405a4a P	213	static int kdf_pbkdf2_get_ctx_params(void *vctx, OSSL_PARAM params[])
	214	{
	215	OSSL_PARAM *p;
5a285add	216
e3405a4a P	217	if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
e3405a4a P	218	return OSSL_PARAM_set_size_t(p, SIZE_MAX);
5a285add DM	219	return -2;
	220	}
	221
e3405a4a	222	static const OSSL_PARAM *kdf_pbkdf2_gettable_ctx_params(void)
5a285add	223	{
e3405a4a P	224	static const OSSL_PARAM known_gettable_ctx_params[] = {
	225	OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
	226	OSSL_PARAM_END
	227	};
	228	return known_gettable_ctx_params;
5a285add DM	229	}
5a285add DM	230
e3405a4a P	231	const OSSL_DISPATCH kdf_pbkdf2_functions[] = {
	232	{ OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_pbkdf2_new },
	233	{ OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_pbkdf2_free },
	234	{ OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_pbkdf2_reset },
	235	{ OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_pbkdf2_derive },
	236	{ OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
	237	(void(*)(void))kdf_pbkdf2_settable_ctx_params },
	238	{ OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_pbkdf2_set_ctx_params },
	239	{ OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
	240	(void(*)(void))kdf_pbkdf2_gettable_ctx_params },
	241	{ OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_pbkdf2_get_ctx_params },
	242	{ 0, NULL }
5a285add DM	243	};
	244
	245	/*
	246	* This is an implementation of PKCS#5 v2.0 password based encryption key
	247	* derivation function PBKDF2. SHA1 version verified against test vectors
	248	* posted by Peter Gutmann to the PKCS-TNG mailing list.
f0efeea2 SL	249	*
	250	* The constraints specified by SP800-132 have been added i.e.
	251	* - Check the range of the key length.
	252	* - Minimum iteration count of 1000.
	253	* - Randomly-generated portion of the salt shall be at least 128 bits.
5a285add	254	*/
f0efeea2	255	static int pbkdf2_derive(const char *pass, size_t passlen,
e3405a4a	256	const unsigned char *salt, int saltlen, uint64_t iter,
f0efeea2 SL	257	const EVP_MD digest, unsigned char key,
f0efeea2 SL	258	size_t keylen, int lower_bound_checks)
5a285add DM	259	{
	260	int ret = 0;
	261	unsigned char digtmp[EVP_MAX_MD_SIZE], *p, itmp[4];
e3405a4a P	262	int cplen, k, tkeylen, mdlen;
e3405a4a P	263	uint64_t j;
5a285add DM	264	unsigned long i = 1;
	265	HMAC_CTX hctx_tpl = NULL, hctx = NULL;
	266
	267	mdlen = EVP_MD_size(digest);
f0efeea2 SL	268	if (mdlen <= 0)
	269	return 0;
	270
	271	/*
	272	* This check should always be done because keylen / mdlen >= (2^32 - 1)
	273	* results in an overflow of the loop counter 'i'.
	274	*/
	275	if ((keylen / mdlen) >= KDF_PBKDF2_MAX_KEY_LEN_DIGEST_RATIO) {
e3405a4a	276	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LEN);
5a285add	277	return 0;
f0efeea2 SL	278	}
	279
	280	if (lower_bound_checks) {
e3405a4a P	281	if ((keylen * 8) < KDF_PBKDF2_MIN_KEY_LEN_BITS) {
	282	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LEN);
	283	return 0;
	284	}
	285	if (saltlen < KDF_PBKDF2_MIN_SALT_LEN) {
	286	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_SALT_LENGTH);
f0efeea2	287	return 0;
e3405a4a P	288	}
	289	if (iter < KDF_PBKDF2_MIN_ITERATIONS) {
	290	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_ITERATION_COUNT);
	291	return 0;
	292	}
f0efeea2	293	}
5a285add DM	294
	295	hctx_tpl = HMAC_CTX_new();
	296	if (hctx_tpl == NULL)
	297	return 0;
	298	p = key;
	299	tkeylen = keylen;
	300	if (!HMAC_Init_ex(hctx_tpl, pass, passlen, digest, NULL))
	301	goto err;
	302	hctx = HMAC_CTX_new();
	303	if (hctx == NULL)
	304	goto err;
	305	while (tkeylen) {
	306	if (tkeylen > mdlen)
	307	cplen = mdlen;
	308	else
	309	cplen = tkeylen;
	310	/*
	311	* We are unlikely to ever use more than 256 blocks (5120 bits!) but
	312	* just in case...
	313	*/
	314	itmp[0] = (unsigned char)((i >> 24) & 0xff);
	315	itmp[1] = (unsigned char)((i >> 16) & 0xff);
	316	itmp[2] = (unsigned char)((i >> 8) & 0xff);
	317	itmp[3] = (unsigned char)(i & 0xff);
	318	if (!HMAC_CTX_copy(hctx, hctx_tpl))
	319	goto err;
	320	if (!HMAC_Update(hctx, salt, saltlen)
	321	\|\| !HMAC_Update(hctx, itmp, 4)
	322	\|\| !HMAC_Final(hctx, digtmp, NULL))
	323	goto err;
	324	memcpy(p, digtmp, cplen);
	325	for (j = 1; j < iter; j++) {
	326	if (!HMAC_CTX_copy(hctx, hctx_tpl))
	327	goto err;
	328	if (!HMAC_Update(hctx, digtmp, mdlen)
	329	\|\| !HMAC_Final(hctx, digtmp, NULL))
	330	goto err;
	331	for (k = 0; k < cplen; k++)
	332	p[k] ^= digtmp[k];
	333	}
	334	tkeylen -= cplen;
	335	i++;
	336	p += cplen;
	337	}
	338	ret = 1;
	339
	340	err:
	341	HMAC_CTX_free(hctx);
	342	HMAC_CTX_free(hctx_tpl);
	343	return ret;
	344	}