/src/openssl/providers/implementations/kdfs/pbkdf2.c

Source
/*
 * Copyright 2018-2025 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 <openssl/proverr.h>
#include "internal/cryptlib.h"
#include "internal/numbers.h"
#include "crypto/evp.h"
#include "prov/provider_ctx.h"
#include "prov/providercommon.h"
#include "prov/implementations.h"
#include "prov/provider_util.h"
#include "prov/securitycheck.h"
#include "providers/implementations/kdfs/pbkdf2.inc"

/* 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_FUNC_kdf_newctx_fn kdf_pbkdf2_new;
static OSSL_FUNC_kdf_dupctx_fn kdf_pbkdf2_dup;
static OSSL_FUNC_kdf_freectx_fn kdf_pbkdf2_free;
static OSSL_FUNC_kdf_reset_fn kdf_pbkdf2_reset;
static OSSL_FUNC_kdf_derive_fn kdf_pbkdf2_derive;
static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_pbkdf2_settable_ctx_params;
static OSSL_FUNC_kdf_set_ctx_params_fn kdf_pbkdf2_set_ctx_params;
static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_pbkdf2_gettable_ctx_params;
static OSSL_FUNC_kdf_get_ctx_params_fn kdf_pbkdf2_get_ctx_params;

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;
    OSSL_FIPS_IND_DECLARE
} KDF_PBKDF2;

static int pbkdf2_derive(KDF_PBKDF2 *ctx, 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);

static void kdf_pbkdf2_init(KDF_PBKDF2 *ctx);

static void *kdf_pbkdf2_new_no_init(void *provctx)
{
    KDF_PBKDF2 *ctx;

    if (!ossl_prov_is_running())
        return NULL;

    ctx = OPENSSL_zalloc(sizeof(*ctx));
    if (ctx == NULL)
        return NULL;
    ctx->provctx = provctx;
    OSSL_FIPS_IND_INIT(ctx);
    return ctx;
}

static void *kdf_pbkdf2_new(void *provctx)
{
    KDF_PBKDF2 *ctx = kdf_pbkdf2_new_no_init(provctx);

    if (ctx != NULL)
        kdf_pbkdf2_init(ctx);
    return ctx;
}

static void kdf_pbkdf2_cleanup(KDF_PBKDF2 *ctx)
{
    ossl_prov_digest_reset(&ctx->digest);
#ifdef OPENSSL_PEDANTIC_ZEROIZATION
    OPENSSL_clear_free(ctx->salt, ctx->salt_len);
#else
    OPENSSL_free(ctx->salt);
#endif
    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;
    void *provctx = ctx->provctx;

    kdf_pbkdf2_cleanup(ctx);
    ctx->provctx = provctx;
    kdf_pbkdf2_init(ctx);
}

static void *kdf_pbkdf2_dup(void *vctx)
{
    const KDF_PBKDF2 *src = (const KDF_PBKDF2 *)vctx;
    KDF_PBKDF2 *dest;

    /* We need a new PBKDF2 object but uninitialised since we're filling it */
    dest = kdf_pbkdf2_new_no_init(src->provctx);
    if (dest != NULL) {
        if (!ossl_prov_memdup(src->salt, src->salt_len,
                              &dest->salt, &dest->salt_len)
                || !ossl_prov_memdup(src->pass, src->pass_len,
                                     &dest->pass, &dest->pass_len)
                || !ossl_prov_digest_copy(&dest->digest, &src->digest))
            goto err;
        dest->iter = src->iter;
        dest->lower_bound_checks = src->lower_bound_checks;
        OSSL_FIPS_IND_COPY(dest, src)
    }
    return dest;

 err:
    kdf_pbkdf2_free(dest);
    return NULL;
}

static void kdf_pbkdf2_init(KDF_PBKDF2 *ctx)
{
    OSSL_PARAM param;
    OSSL_LIB_CTX *provctx = PROV_LIBCTX_OF(ctx->provctx);

    param = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
                                             SN_sha1, 0);
    if (!ossl_prov_digest_load(&ctx->digest, &param, NULL, NULL, 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;
#ifdef FIPS_MODULE
    ctx->lower_bound_checks = 1;
#else
    ctx->lower_bound_checks = 0;
#endif
}

static int pbkdf2_set_membuf(unsigned char **buffer, size_t *buflen,
                             const OSSL_PARAM *p)
{
    OPENSSL_clear_free(*buffer, *buflen);
    *buffer = NULL;
    *buflen = 0;

    if (p->data_size == 0) {
        if ((*buffer = OPENSSL_malloc(1)) == NULL)
            return 0;
    } else if (p->data != NULL) {
        if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
            return 0;
    }
    return 1;
}

static int pbkdf2_lower_bound_check_passed(int saltlen, uint64_t iter,
                                           size_t keylen, int *error,
                                           const char **desc)
{
    if ((keylen * 8) < KDF_PBKDF2_MIN_KEY_LEN_BITS) {
        *error = PROV_R_KEY_SIZE_TOO_SMALL;
        if (desc != NULL)
            *desc = "Key size";
        return 0;
    }
    if (saltlen < KDF_PBKDF2_MIN_SALT_LEN) {
        *error = PROV_R_INVALID_SALT_LENGTH;
        if (desc != NULL)
            *desc = "Salt size";
        return 0;
    }
    if (iter < KDF_PBKDF2_MIN_ITERATIONS) {
        *error = PROV_R_INVALID_ITERATION_COUNT;
        if (desc != NULL)
            *desc = "Iteration count";
        return 0;
    }

    return 1;
}

#ifdef FIPS_MODULE
static int fips_lower_bound_check_passed(KDF_PBKDF2 *ctx, int saltlen,
                                         uint64_t iter, size_t keylen)
{
    OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
    int error = 0;
    const char *desc = NULL;
    int approved = pbkdf2_lower_bound_check_passed(saltlen, iter, keylen,
                                                   &error, &desc);

    if (!approved) {
        if (!OSSL_FIPS_IND_ON_UNAPPROVED(ctx, OSSL_FIPS_IND_SETTABLE0, libctx,
                                         "PBKDF2", desc,
                                         ossl_fips_config_pbkdf2_lower_bound_check)) {
            ERR_raise(ERR_LIB_PROV, error);
            return 0;
        }
    }
    return 1;
}
#endif

static int lower_bound_check_passed(KDF_PBKDF2 *ctx, int saltlen, uint64_t iter,
                                    size_t keylen, int lower_bound_checks)
{
#ifdef FIPS_MODULE
    if (!fips_lower_bound_check_passed(ctx, saltlen, iter, keylen))
        return 0;
#else
    if (lower_bound_checks) {
        int error = 0;
        int passed = pbkdf2_lower_bound_check_passed(saltlen, iter, keylen,
                                                     &error, NULL);

        if (!passed) {
            ERR_raise(ERR_LIB_PROV, error);
            return 0;
        }
    } else if (iter < 1) {
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_ITERATION_COUNT);
        return 0;
    }
#endif

    return 1;
}

static int kdf_pbkdf2_derive(void *vctx, unsigned char *key, size_t keylen,
                             const OSSL_PARAM params[])
{
    KDF_PBKDF2 *ctx = (KDF_PBKDF2 *)vctx;
    const EVP_MD *md;

    if (!ossl_prov_is_running() || !kdf_pbkdf2_set_ctx_params(ctx, params))
        return 0;

    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;
    }

    md = ossl_prov_digest_md(&ctx->digest);
    return pbkdf2_derive(ctx, (char *)ctx->pass, ctx->pass_len,
                         ctx->salt, (int)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[])
{
    struct pbkdf2_set_ctx_params_st p;
    KDF_PBKDF2 *ctx = vctx;
    OSSL_LIB_CTX *provctx;
    int pkcs5;
    uint64_t iter;
    const EVP_MD *md;

    if (ctx == NULL || !pbkdf2_set_ctx_params_decoder(params, &p))
        return 0;

    provctx = PROV_LIBCTX_OF(ctx->provctx);

    if (p.digest != NULL) {
        if (!ossl_prov_digest_load(&ctx->digest, p.digest,
                                   p.propq, p.engine, provctx))
            return 0;
        md = ossl_prov_digest_md(&ctx->digest);
        if (EVP_MD_xof(md)) {
            ERR_raise(ERR_LIB_PROV, PROV_R_XOF_DIGESTS_NOT_ALLOWED);
            return 0;
        }
    }

    if (p.pkcs5 != NULL) {
        if (!OSSL_PARAM_get_int(p.pkcs5, &pkcs5))
            return 0;
        ctx->lower_bound_checks = pkcs5 == 0;
#ifdef FIPS_MODULE
        ossl_FIPS_IND_set_settable(OSSL_FIPS_IND_GET(ctx),
                                   OSSL_FIPS_IND_SETTABLE0,
                                   ctx->lower_bound_checks);
#endif
    }

    if (p.pw != NULL && !pbkdf2_set_membuf(&ctx->pass, &ctx->pass_len, p.pw))
            return 0;

    if (p.salt != NULL) {
        if (!lower_bound_check_passed(ctx, (int)p.salt->data_size, UINT64_MAX, SIZE_MAX,
                                      ctx->lower_bound_checks))
            return 0;
        if (!pbkdf2_set_membuf(&ctx->salt, &ctx->salt_len, p.salt))
            return 0;
    }

    if (p.iter != NULL) {
        if (!OSSL_PARAM_get_uint64(p.iter, &iter))
            return 0;
        if (!lower_bound_check_passed(ctx, INT_MAX, iter, SIZE_MAX,
                                      ctx->lower_bound_checks))
            return 0;
        ctx->iter = iter;
    }
    return 1;
}

static const OSSL_PARAM *kdf_pbkdf2_settable_ctx_params(ossl_unused void *ctx,
                                                        ossl_unused void *p_ctx)
{
    return pbkdf2_set_ctx_params_list;
}

static int kdf_pbkdf2_get_ctx_params(void *vctx, OSSL_PARAM params[])
{
    KDF_PBKDF2 *ctx = vctx;
    struct pbkdf2_get_ctx_params_st p;

    if (ctx == NULL || !pbkdf2_get_ctx_params_decoder(params, &p))
        return 0;

    if (p.size != NULL && !OSSL_PARAM_set_size_t(p.size, SIZE_MAX))
            return 0;

    if (!OSSL_FIPS_IND_GET_CTX_FROM_PARAM(ctx, p.ind))
        return 0;
    return 1;
}

static const OSSL_PARAM *kdf_pbkdf2_gettable_ctx_params(ossl_unused void *ctx,
                                                        ossl_unused void *p_ctx)
{
    return pbkdf2_get_ctx_params_list;
}

const OSSL_DISPATCH ossl_kdf_pbkdf2_functions[] = {
    { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_pbkdf2_new },
    { OSSL_FUNC_KDF_DUPCTX, (void(*)(void))kdf_pbkdf2_dup },
    { 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 },
    OSSL_DISPATCH_END
};

/*
 * 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(KDF_PBKDF2 *ctx, 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_get_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_LENGTH);
        return 0;
    }

    if (!lower_bound_check_passed(ctx, saltlen, iter, keylen, lower_bound_checks))
        return 0;

    hctx_tpl = HMAC_CTX_new();
    if (hctx_tpl == NULL)
        return 0;
    p = key;
    tkeylen = (int)keylen;
    if (!HMAC_Init_ex(hctx_tpl, pass, (int)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;
}

Coverage Report

Created: 2025-10-28 06:56

Line	Count	Source
1		/*
2		* Copyright 2018-2025 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 <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>
22		#include <openssl/core_names.h>
23		#include <openssl/proverr.h>
24		#include "internal/cryptlib.h"
25		#include "internal/numbers.h"
26		#include "crypto/evp.h"
27		#include "prov/provider_ctx.h"
28		#include "prov/providercommon.h"
29		#include "prov/implementations.h"
30		#include "prov/provider_util.h"
31		#include "prov/securitycheck.h"
32		#include "providers/implementations/kdfs/pbkdf2.inc"
33
34		/* Constants specified in SP800-132 */
35	0	#define KDF_PBKDF2_MIN_KEY_LEN_BITS 112
36	0	#define KDF_PBKDF2_MAX_KEY_LEN_DIGEST_RATIO 0xFFFFFFFF
37	0	#define KDF_PBKDF2_MIN_ITERATIONS 1000
38	0	#define KDF_PBKDF2_MIN_SALT_LEN (128 / 8)
39
40		static OSSL_FUNC_kdf_newctx_fn kdf_pbkdf2_new;
41		static OSSL_FUNC_kdf_dupctx_fn kdf_pbkdf2_dup;
42		static OSSL_FUNC_kdf_freectx_fn kdf_pbkdf2_free;
43		static OSSL_FUNC_kdf_reset_fn kdf_pbkdf2_reset;
44		static OSSL_FUNC_kdf_derive_fn kdf_pbkdf2_derive;
45		static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_pbkdf2_settable_ctx_params;
46		static OSSL_FUNC_kdf_set_ctx_params_fn kdf_pbkdf2_set_ctx_params;
47		static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_pbkdf2_gettable_ctx_params;
48		static OSSL_FUNC_kdf_get_ctx_params_fn kdf_pbkdf2_get_ctx_params;
49
50		typedef struct {
51		void *provctx;
52		unsigned char *pass;
53		size_t pass_len;
54		unsigned char *salt;
55		size_t salt_len;
56		uint64_t iter;
57		PROV_DIGEST digest;
58		int lower_bound_checks;
59		OSSL_FIPS_IND_DECLARE
60		} KDF_PBKDF2;
61
62		static int pbkdf2_derive(KDF_PBKDF2 ctx, const char pass, size_t passlen,
63		const unsigned char *salt, int saltlen, uint64_t iter,
64		const EVP_MD digest, unsigned char key,
65		size_t keylen, int lower_bound_checks);
66
67		static void kdf_pbkdf2_init(KDF_PBKDF2 *ctx);
68
69		static void kdf_pbkdf2_new_no_init(void provctx)
70	0	{
71	0	KDF_PBKDF2 *ctx;
72
73	0	if (!ossl_prov_is_running())
74	0	return NULL;
75
76	0	ctx = OPENSSL_zalloc(sizeof(*ctx));
77	0	if (ctx == NULL)
78	0	return NULL;
79	0	ctx->provctx = provctx;
80	0	OSSL_FIPS_IND_INIT(ctx);
81	0	return ctx;
82	0	}
83
84		static void kdf_pbkdf2_new(void provctx)
85	0	{
86	0	KDF_PBKDF2 *ctx = kdf_pbkdf2_new_no_init(provctx);
87
88	0	if (ctx != NULL)
89	0	kdf_pbkdf2_init(ctx);
90	0	return ctx;
91	0	}
92
93		static void kdf_pbkdf2_cleanup(KDF_PBKDF2 *ctx)
94	0	{
95	0	ossl_prov_digest_reset(&ctx->digest);
96		#ifdef OPENSSL_PEDANTIC_ZEROIZATION
97		OPENSSL_clear_free(ctx->salt, ctx->salt_len);
98		#else
99	0	OPENSSL_free(ctx->salt);
100	0	#endif
101	0	OPENSSL_clear_free(ctx->pass, ctx->pass_len);
102	0	memset(ctx, 0, sizeof(*ctx));
103	0	}
104
105		static void kdf_pbkdf2_free(void *vctx)
106	0	{
107	0	KDF_PBKDF2 ctx = (KDF_PBKDF2 )vctx;
108
109	0	if (ctx != NULL) {
110	0	kdf_pbkdf2_cleanup(ctx);
111	0	OPENSSL_free(ctx);
112	0	}
113	0	}
114
115		static void kdf_pbkdf2_reset(void *vctx)
116	0	{
117	0	KDF_PBKDF2 ctx = (KDF_PBKDF2 )vctx;
118	0	void *provctx = ctx->provctx;
119
120	0	kdf_pbkdf2_cleanup(ctx);
121	0	ctx->provctx = provctx;
122	0	kdf_pbkdf2_init(ctx);
123	0	}
124
125		static void kdf_pbkdf2_dup(void vctx)
126	0	{
127	0	const KDF_PBKDF2 src = (const KDF_PBKDF2 )vctx;
128	0	KDF_PBKDF2 *dest;
129
130		/* We need a new PBKDF2 object but uninitialised since we're filling it */
131	0	dest = kdf_pbkdf2_new_no_init(src->provctx);
132	0	if (dest != NULL) {
133	0	if (!ossl_prov_memdup(src->salt, src->salt_len,
134	0	&dest->salt, &dest->salt_len)
135	0	\|\| !ossl_prov_memdup(src->pass, src->pass_len,
136	0	&dest->pass, &dest->pass_len)
137	0	\|\| !ossl_prov_digest_copy(&dest->digest, &src->digest))
138	0	goto err;
139	0	dest->iter = src->iter;
140	0	dest->lower_bound_checks = src->lower_bound_checks;
141	0	OSSL_FIPS_IND_COPY(dest, src)
142	0	}
143	0	return dest;
144
145	0	err:
146	0	kdf_pbkdf2_free(dest);
147	0	return NULL;
148	0	}
149
150		static void kdf_pbkdf2_init(KDF_PBKDF2 *ctx)
151	0	{
152	0	OSSL_PARAM param;
153	0	OSSL_LIB_CTX *provctx = PROV_LIBCTX_OF(ctx->provctx);
154
155	0	param = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
156	0	SN_sha1, 0);
157	0	if (!ossl_prov_digest_load(&ctx->digest, &param, NULL, NULL, provctx))
158		/* This is an error, but there is no way to indicate such directly */
159	0	ossl_prov_digest_reset(&ctx->digest);
160	0	ctx->iter = PKCS5_DEFAULT_ITER;
161		#ifdef FIPS_MODULE
162		ctx->lower_bound_checks = 1;
163		#else
164	0	ctx->lower_bound_checks = 0;
165	0	#endif
166	0	}
167
168		static int pbkdf2_set_membuf(unsigned char *buffer, size_t buflen,
169		const OSSL_PARAM *p)
170	0	{
171	0	OPENSSL_clear_free(buffer, buflen);
172	0	*buffer = NULL;
173	0	*buflen = 0;
174
175	0	if (p->data_size == 0) {
176	0	if ((*buffer = OPENSSL_malloc(1)) == NULL)
177	0	return 0;
178	0	} else if (p->data != NULL) {
179	0	if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
180	0	return 0;
181	0	}
182	0	return 1;
183	0	}
184
185		static int pbkdf2_lower_bound_check_passed(int saltlen, uint64_t iter,
186		size_t keylen, int *error,
187		const char **desc)
188	0	{
189	0	if ((keylen * 8) < KDF_PBKDF2_MIN_KEY_LEN_BITS) {
190	0	*error = PROV_R_KEY_SIZE_TOO_SMALL;
191	0	if (desc != NULL)
192	0	*desc = "Key size";
193	0	return 0;
194	0	}
195	0	if (saltlen < KDF_PBKDF2_MIN_SALT_LEN) {
196	0	*error = PROV_R_INVALID_SALT_LENGTH;
197	0	if (desc != NULL)
198	0	*desc = "Salt size";
199	0	return 0;
200	0	}
201	0	if (iter < KDF_PBKDF2_MIN_ITERATIONS) {
202	0	*error = PROV_R_INVALID_ITERATION_COUNT;
203	0	if (desc != NULL)
204	0	*desc = "Iteration count";
205	0	return 0;
206	0	}
207
208	0	return 1;
209	0	}
210
211		#ifdef FIPS_MODULE
212		static int fips_lower_bound_check_passed(KDF_PBKDF2 *ctx, int saltlen,
213		uint64_t iter, size_t keylen)
214		{
215		OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
216		int error = 0;
217		const char *desc = NULL;
218		int approved = pbkdf2_lower_bound_check_passed(saltlen, iter, keylen,
219		&error, &desc);
220
221		if (!approved) {
222		if (!OSSL_FIPS_IND_ON_UNAPPROVED(ctx, OSSL_FIPS_IND_SETTABLE0, libctx,
223		"PBKDF2", desc,
224		ossl_fips_config_pbkdf2_lower_bound_check)) {
225		ERR_raise(ERR_LIB_PROV, error);
226		return 0;
227		}
228		}
229		return 1;
230		}
231		#endif
232
233		static int lower_bound_check_passed(KDF_PBKDF2 *ctx, int saltlen, uint64_t iter,
234		size_t keylen, int lower_bound_checks)
235	0	{
236		#ifdef FIPS_MODULE
237		if (!fips_lower_bound_check_passed(ctx, saltlen, iter, keylen))
238		return 0;
239		#else
240	0	if (lower_bound_checks) {
241	0	int error = 0;
242	0	int passed = pbkdf2_lower_bound_check_passed(saltlen, iter, keylen,
243	0	&error, NULL);
244
245	0	if (!passed) {
246	0	ERR_raise(ERR_LIB_PROV, error);
247	0	return 0;
248	0	}
249	0	} else if (iter < 1) {
250	0	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_ITERATION_COUNT);
251	0	return 0;
252	0	}
253	0	#endif
254
255	0	return 1;
256	0	}
257
258		static int kdf_pbkdf2_derive(void vctx, unsigned char key, size_t keylen,
259		const OSSL_PARAM params[])
260	0	{
261	0	KDF_PBKDF2 ctx = (KDF_PBKDF2 )vctx;
262	0	const EVP_MD *md;
263
264	0	if (!ossl_prov_is_running() \|\| !kdf_pbkdf2_set_ctx_params(ctx, params))
265	0	return 0;
266
267	0	if (ctx->pass == NULL) {
268	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
269	0	return 0;
270	0	}
271
272	0	if (ctx->salt == NULL) {
273	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
274	0	return 0;
275	0	}
276
277	0	md = ossl_prov_digest_md(&ctx->digest);
278	0	return pbkdf2_derive(ctx, (char *)ctx->pass, ctx->pass_len,
279	0	ctx->salt, (int)ctx->salt_len, ctx->iter,
280	0	md, key, keylen, ctx->lower_bound_checks);
281	0	}
282
283		static int kdf_pbkdf2_set_ctx_params(void *vctx, const OSSL_PARAM params[])
284	0	{
285	0	struct pbkdf2_set_ctx_params_st p;
286	0	KDF_PBKDF2 *ctx = vctx;
287	0	OSSL_LIB_CTX *provctx;
288	0	int pkcs5;
289	0	uint64_t iter;
290	0	const EVP_MD *md;
291
292	0	if (ctx == NULL \|\| !pbkdf2_set_ctx_params_decoder(params, &p))
293	0	return 0;
294
295	0	provctx = PROV_LIBCTX_OF(ctx->provctx);
296
297	0	if (p.digest != NULL) {
298	0	if (!ossl_prov_digest_load(&ctx->digest, p.digest,
299	0	p.propq, p.engine, provctx))
300	0	return 0;
301	0	md = ossl_prov_digest_md(&ctx->digest);
302	0	if (EVP_MD_xof(md)) {
303	0	ERR_raise(ERR_LIB_PROV, PROV_R_XOF_DIGESTS_NOT_ALLOWED);
304	0	return 0;
305	0	}
306	0	}
307
308	0	if (p.pkcs5 != NULL) {
309	0	if (!OSSL_PARAM_get_int(p.pkcs5, &pkcs5))
310	0	return 0;
311	0	ctx->lower_bound_checks = pkcs5 == 0;
312		#ifdef FIPS_MODULE
313		ossl_FIPS_IND_set_settable(OSSL_FIPS_IND_GET(ctx),
314		OSSL_FIPS_IND_SETTABLE0,
315		ctx->lower_bound_checks);
316		#endif
317	0	}
318
319	0	if (p.pw != NULL && !pbkdf2_set_membuf(&ctx->pass, &ctx->pass_len, p.pw))
320	0	return 0;
321
322	0	if (p.salt != NULL) {
323	0	if (!lower_bound_check_passed(ctx, (int)p.salt->data_size, UINT64_MAX, SIZE_MAX,
324	0	ctx->lower_bound_checks))
325	0	return 0;
326	0	if (!pbkdf2_set_membuf(&ctx->salt, &ctx->salt_len, p.salt))
327	0	return 0;
328	0	}
329
330	0	if (p.iter != NULL) {
331	0	if (!OSSL_PARAM_get_uint64(p.iter, &iter))
332	0	return 0;
333	0	if (!lower_bound_check_passed(ctx, INT_MAX, iter, SIZE_MAX,
334	0	ctx->lower_bound_checks))
335	0	return 0;
336	0	ctx->iter = iter;
337	0	}
338	0	return 1;
339	0	}
340
341		static const OSSL_PARAM kdf_pbkdf2_settable_ctx_params(ossl_unused void ctx,
342		ossl_unused void *p_ctx)
343	0	{
344	0	return pbkdf2_set_ctx_params_list;
345	0	}
346
347		static int kdf_pbkdf2_get_ctx_params(void *vctx, OSSL_PARAM params[])
348	0	{
349	0	KDF_PBKDF2 *ctx = vctx;
350	0	struct pbkdf2_get_ctx_params_st p;
351
352	0	if (ctx == NULL \|\| !pbkdf2_get_ctx_params_decoder(params, &p))
353	0	return 0;
354
355	0	if (p.size != NULL && !OSSL_PARAM_set_size_t(p.size, SIZE_MAX))
356	0	return 0;
357
358	0	if (!OSSL_FIPS_IND_GET_CTX_FROM_PARAM(ctx, p.ind))
359	0	return 0;
360	0	return 1;
361	0	}
362
363		static const OSSL_PARAM kdf_pbkdf2_gettable_ctx_params(ossl_unused void ctx,
364		ossl_unused void *p_ctx)
365	0	{
366	0	return pbkdf2_get_ctx_params_list;
367	0	}
368
369		const OSSL_DISPATCH ossl_kdf_pbkdf2_functions[] = {
370		{ OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_pbkdf2_new },
371		{ OSSL_FUNC_KDF_DUPCTX, (void(*)(void))kdf_pbkdf2_dup },
372		{ OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_pbkdf2_free },
373		{ OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_pbkdf2_reset },
374		{ OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_pbkdf2_derive },
375		{ OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
376		(void(*)(void))kdf_pbkdf2_settable_ctx_params },
377		{ OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_pbkdf2_set_ctx_params },
378		{ OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
379		(void(*)(void))kdf_pbkdf2_gettable_ctx_params },
380		{ OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_pbkdf2_get_ctx_params },
381		OSSL_DISPATCH_END
382		};
383
384		/*
385		* This is an implementation of PKCS#5 v2.0 password based encryption key
386		* derivation function PBKDF2. SHA1 version verified against test vectors
387		* posted by Peter Gutmann to the PKCS-TNG mailing list.
388		*
389		* The constraints specified by SP800-132 have been added i.e.
390		* - Check the range of the key length.
391		* - Minimum iteration count of 1000.
392		* - Randomly-generated portion of the salt shall be at least 128 bits.
393		*/
394		static int pbkdf2_derive(KDF_PBKDF2 ctx, const char pass, size_t passlen,
395		const unsigned char *salt, int saltlen, uint64_t iter,
396		const EVP_MD digest, unsigned char key,
397		size_t keylen, int lower_bound_checks)
398	0	{
399	0	int ret = 0;
400	0	unsigned char digtmp[EVP_MAX_MD_SIZE], *p, itmp[4];
401	0	int cplen, k, tkeylen, mdlen;
402	0	uint64_t j;
403	0	unsigned long i = 1;
404	0	HMAC_CTX hctx_tpl = NULL, hctx = NULL;
405
406	0	mdlen = EVP_MD_get_size(digest);
407	0	if (mdlen <= 0)
408	0	return 0;
409
410		/*
411		* This check should always be done because keylen / mdlen >= (2^32 - 1)
412		* results in an overflow of the loop counter 'i'.
413		*/
414	0	if ((keylen / mdlen) >= KDF_PBKDF2_MAX_KEY_LEN_DIGEST_RATIO) {
415	0	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
416	0	return 0;
417	0	}
418
419	0	if (!lower_bound_check_passed(ctx, saltlen, iter, keylen, lower_bound_checks))
420	0	return 0;
421
422	0	hctx_tpl = HMAC_CTX_new();
423	0	if (hctx_tpl == NULL)
424	0	return 0;
425	0	p = key;
426	0	tkeylen = (int)keylen;
427	0	if (!HMAC_Init_ex(hctx_tpl, pass, (int)passlen, digest, NULL))
428	0	goto err;
429	0	hctx = HMAC_CTX_new();
430	0	if (hctx == NULL)
431	0	goto err;
432	0	while (tkeylen) {
433	0	if (tkeylen > mdlen)
434	0	cplen = mdlen;
435	0	else
436	0	cplen = tkeylen;
437		/*
438		* We are unlikely to ever use more than 256 blocks (5120 bits!) but
439		* just in case...
440		*/
441	0	itmp[0] = (unsigned char)((i >> 24) & 0xff);
442	0	itmp[1] = (unsigned char)((i >> 16) & 0xff);
443	0	itmp[2] = (unsigned char)((i >> 8) & 0xff);
444	0	itmp[3] = (unsigned char)(i & 0xff);
445	0	if (!HMAC_CTX_copy(hctx, hctx_tpl))
446	0	goto err;
447	0	if (!HMAC_Update(hctx, salt, saltlen)
448	0	\|\| !HMAC_Update(hctx, itmp, 4)
449	0	\|\| !HMAC_Final(hctx, digtmp, NULL))
450	0	goto err;
451	0	memcpy(p, digtmp, cplen);
452	0	for (j = 1; j < iter; j++) {
453	0	if (!HMAC_CTX_copy(hctx, hctx_tpl))
454	0	goto err;
455	0	if (!HMAC_Update(hctx, digtmp, mdlen)
456	0	\|\| !HMAC_Final(hctx, digtmp, NULL))
457	0	goto err;
458	0	for (k = 0; k < cplen; k++)
459	0	p[k] ^= digtmp[k];
460	0	}
461	0	tkeylen -= cplen;
462	0	i++;
463	0	p += cplen;
464	0	}
465	0	ret = 1;
466
467	0	err:
468	0	HMAC_CTX_free(hctx);
469	0	HMAC_CTX_free(hctx_tpl);
470	0	return ret;
471	0	}