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

Source (jump to first uncovered line)
/*
 * Copyright 2017-2025 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
 */

#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <openssl/evp.h>
#include <openssl/kdf.h>
#include <openssl/err.h>
#include <openssl/core_names.h>
#include <openssl/proverr.h>
#include "crypto/evp.h"
#include "internal/numbers.h"
#include "prov/implementations.h"
#include "prov/provider_ctx.h"
#include "prov/providercommon.h"
#include "prov/implementations.h"

#ifndef OPENSSL_NO_SCRYPT

static OSSL_FUNC_kdf_newctx_fn kdf_scrypt_new;
static OSSL_FUNC_kdf_freectx_fn kdf_scrypt_free;
static OSSL_FUNC_kdf_reset_fn kdf_scrypt_reset;
static OSSL_FUNC_kdf_derive_fn kdf_scrypt_derive;
static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_scrypt_settable_ctx_params;
static OSSL_FUNC_kdf_set_ctx_params_fn kdf_scrypt_set_ctx_params;
static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_scrypt_gettable_ctx_params;
static OSSL_FUNC_kdf_get_ctx_params_fn kdf_scrypt_get_ctx_params;

static int scrypt_alg(const char *pass, size_t passlen,
                      const unsigned char *salt, size_t saltlen,
                      uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
                      unsigned char *key, size_t keylen, EVP_MD *sha256,
                      OSSL_LIB_CTX *libctx, const char *propq);

typedef struct {
    OSSL_LIB_CTX *libctx;
    char *propq;
    unsigned char *pass;
    size_t pass_len;
    unsigned char *salt;
    size_t salt_len;
    uint64_t N;
    uint64_t r, p;
    uint64_t maxmem_bytes;
    EVP_MD *sha256;
} KDF_SCRYPT;

static void kdf_scrypt_init(KDF_SCRYPT *ctx);

static void *kdf_scrypt_new(void *provctx)
{
    KDF_SCRYPT *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->libctx = PROV_LIBCTX_OF(provctx);
    kdf_scrypt_init(ctx);
    return ctx;
}

static void kdf_scrypt_free(void *vctx)
{
    KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;

    if (ctx != NULL) {
        OPENSSL_free(ctx->propq);
        EVP_MD_free(ctx->sha256);
        kdf_scrypt_reset(ctx);
        OPENSSL_free(ctx);
    }
}

static void kdf_scrypt_reset(void *vctx)
{
    KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;

    OPENSSL_free(ctx->salt);
    ctx->salt = NULL;
    OPENSSL_clear_free(ctx->pass, ctx->pass_len);
    ctx->pass = NULL;
    kdf_scrypt_init(ctx);
}

static void kdf_scrypt_init(KDF_SCRYPT *ctx)
{
    /* Default values are the most conservative recommendation given in the
     * original paper of C. Percival. Derivation uses roughly 1 GiB of memory
     * for this parameter choice (approx. 128 * r * N * p bytes).
     */
    ctx->N = 1 << 20;
    ctx->r = 8;
    ctx->p = 1;
    ctx->maxmem_bytes = 1025 * 1024 * 1024;
}

static int scrypt_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) {
            ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
            return 0;
        }
    } else if (p->data != NULL) {
        if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
            return 0;
    }
    return 1;
}

static int set_digest(KDF_SCRYPT *ctx)
{
    EVP_MD_free(ctx->sha256);
    ctx->sha256 = EVP_MD_fetch(ctx->libctx, "sha256", ctx->propq);
    if (ctx->sha256 == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_UNABLE_TO_LOAD_SHA256);
        return 0;
    }
    return 1;
}

static int set_property_query(KDF_SCRYPT *ctx, const char *propq)
{
    OPENSSL_free(ctx->propq);
    ctx->propq = NULL;
    if (propq != NULL) {
        ctx->propq = OPENSSL_strdup(propq);
        if (ctx->propq == NULL) {
            ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
            return 0;
        }
    }
    return 1;
}

static int kdf_scrypt_derive(void *vctx, unsigned char *key, size_t keylen,
                             const OSSL_PARAM params[])
{
    KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;

    if (!ossl_prov_is_running() || !kdf_scrypt_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;
    }

    if (ctx->sha256 == NULL && !set_digest(ctx))
        return 0;

    return scrypt_alg((char *)ctx->pass, ctx->pass_len, ctx->salt,
                      ctx->salt_len, ctx->N, ctx->r, ctx->p,
                      ctx->maxmem_bytes, key, keylen, ctx->sha256,
                      ctx->libctx, ctx->propq);
}

static int is_power_of_two(uint64_t value)
{
    return (value != 0) && ((value & (value - 1)) == 0);
}

static int kdf_scrypt_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
    const OSSL_PARAM *p;
    KDF_SCRYPT *ctx = vctx;
    uint64_t u64_value;

    if (params == NULL)
        return 1;

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

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL)
        if (!scrypt_set_membuf(&ctx->salt, &ctx->salt_len, p))
            return 0;

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_N))
        != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &u64_value)
            || u64_value <= 1
            || !is_power_of_two(u64_value))
            return 0;
        ctx->N = u64_value;
    }

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_R))
        != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
            return 0;
        ctx->r = u64_value;
    }

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_P))
        != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
            return 0;
        ctx->p = u64_value;
    }

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_MAXMEM))
        != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
            return 0;
        ctx->maxmem_bytes = u64_value;
    }

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PROPERTIES);
    if (p != NULL) {
        if (p->data_type != OSSL_PARAM_UTF8_STRING
            || !set_property_query(ctx, p->data)
            || !set_digest(ctx))
            return 0;
    }
    return 1;
}

static const OSSL_PARAM *kdf_scrypt_settable_ctx_params(ossl_unused void *ctx,
                                                        ossl_unused void *p_ctx)
{
    static const OSSL_PARAM known_settable_ctx_params[] = {
        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_SCRYPT_N, NULL),
        OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R, NULL),
        OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P, NULL),
        OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM, NULL),
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
        OSSL_PARAM_END
    };
    return known_settable_ctx_params;
}

static int kdf_scrypt_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_scrypt_gettable_ctx_params(ossl_unused void *ctx,
                                                        ossl_unused void *p_ctx)
{
    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_scrypt_functions[] = {
    { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_scrypt_new },
    { OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_scrypt_free },
    { OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_scrypt_reset },
    { OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_scrypt_derive },
    { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
      (void(*)(void))kdf_scrypt_settable_ctx_params },
    { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_scrypt_set_ctx_params },
    { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
      (void(*)(void))kdf_scrypt_gettable_ctx_params },
    { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_scrypt_get_ctx_params },
    { 0, NULL }
};

#define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
static void salsa208_word_specification(uint32_t inout[16])
{
    int i;
    uint32_t x[16];

    memcpy(x, inout, sizeof(x));
    for (i = 8; i > 0; i -= 2) {
        x[4] ^= R(x[0] + x[12], 7);
        x[8] ^= R(x[4] + x[0], 9);
        x[12] ^= R(x[8] + x[4], 13);
        x[0] ^= R(x[12] + x[8], 18);
        x[9] ^= R(x[5] + x[1], 7);
        x[13] ^= R(x[9] + x[5], 9);
        x[1] ^= R(x[13] + x[9], 13);
        x[5] ^= R(x[1] + x[13], 18);
        x[14] ^= R(x[10] + x[6], 7);
        x[2] ^= R(x[14] + x[10], 9);
        x[6] ^= R(x[2] + x[14], 13);
        x[10] ^= R(x[6] + x[2], 18);
        x[3] ^= R(x[15] + x[11], 7);
        x[7] ^= R(x[3] + x[15], 9);
        x[11] ^= R(x[7] + x[3], 13);
        x[15] ^= R(x[11] + x[7], 18);
        x[1] ^= R(x[0] + x[3], 7);
        x[2] ^= R(x[1] + x[0], 9);
        x[3] ^= R(x[2] + x[1], 13);
        x[0] ^= R(x[3] + x[2], 18);
        x[6] ^= R(x[5] + x[4], 7);
        x[7] ^= R(x[6] + x[5], 9);
        x[4] ^= R(x[7] + x[6], 13);
        x[5] ^= R(x[4] + x[7], 18);
        x[11] ^= R(x[10] + x[9], 7);
        x[8] ^= R(x[11] + x[10], 9);
        x[9] ^= R(x[8] + x[11], 13);
        x[10] ^= R(x[9] + x[8], 18);
        x[12] ^= R(x[15] + x[14], 7);
        x[13] ^= R(x[12] + x[15], 9);
        x[14] ^= R(x[13] + x[12], 13);
        x[15] ^= R(x[14] + x[13], 18);
    }
    for (i = 0; i < 16; ++i)
        inout[i] += x[i];
    OPENSSL_cleanse(x, sizeof(x));
}

static void scryptBlockMix(uint32_t *B_, uint32_t *B, uint64_t r)
{
    uint64_t i, j;
    uint32_t X[16], *pB;

    memcpy(X, B + (r * 2 - 1) * 16, sizeof(X));
    pB = B;
    for (i = 0; i < r * 2; i++) {
        for (j = 0; j < 16; j++)
            X[j] ^= *pB++;
        salsa208_word_specification(X);
        memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X));
    }
    OPENSSL_cleanse(X, sizeof(X));
}

static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N,
                        uint32_t *X, uint32_t *T, uint32_t *V)
{
    unsigned char *pB;
    uint32_t *pV;
    uint64_t i, k;

    /* Convert from little endian input */
    for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) {
        *pV = *pB++;
        *pV |= *pB++ << 8;
        *pV |= *pB++ << 16;
        *pV |= (uint32_t)*pB++ << 24;
    }

    for (i = 1; i < N; i++, pV += 32 * r)
        scryptBlockMix(pV, pV - 32 * r, r);

    scryptBlockMix(X, V + (N - 1) * 32 * r, r);

    for (i = 0; i < N; i++) {
        uint32_t j;
        j = X[16 * (2 * r - 1)] % N;
        pV = V + 32 * r * j;
        for (k = 0; k < 32 * r; k++)
            T[k] = X[k] ^ *pV++;
        scryptBlockMix(X, T, r);
    }
    /* Convert output to little endian */
    for (i = 0, pB = B; i < 32 * r; i++) {
        uint32_t xtmp = X[i];
        *pB++ = xtmp & 0xff;
        *pB++ = (xtmp >> 8) & 0xff;
        *pB++ = (xtmp >> 16) & 0xff;
        *pB++ = (xtmp >> 24) & 0xff;
    }
}

#ifndef SIZE_MAX
# define SIZE_MAX    ((size_t)-1)
#endif

/*
 * Maximum power of two that will fit in uint64_t: this should work on
 * most (all?) platforms.
 */

#define LOG2_UINT64_MAX         (sizeof(uint64_t) * 8 - 1)

/*
 * Maximum value of p * r:
 * p <= ((2^32-1) * hLen) / MFLen =>
 * p <= ((2^32-1) * 32) / (128 * r) =>
 * p * r <= (2^30-1)
 */

#define SCRYPT_PR_MAX   ((1 << 30) - 1)

static int scrypt_alg(const char *pass, size_t passlen,
                      const unsigned char *salt, size_t saltlen,
                      uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
                      unsigned char *key, size_t keylen, EVP_MD *sha256,
                      OSSL_LIB_CTX *libctx, const char *propq)
{
    int rv = 0;
    unsigned char *B;
    uint32_t *X, *V, *T;
    uint64_t i, Blen, Vlen;

    /* Sanity check parameters */
    /* initial check, r,p must be non zero, N >= 2 and a power of 2 */
    if (r == 0 || p == 0 || N < 2 || (N & (N - 1)))
        return 0;
    /* Check p * r < SCRYPT_PR_MAX avoiding overflow */
    if (p > SCRYPT_PR_MAX / r) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }

    /*
     * Need to check N: if 2^(128 * r / 8) overflows limit this is
     * automatically satisfied since N <= UINT64_MAX.
     */

    if (16 * r <= LOG2_UINT64_MAX) {
        if (N >= (((uint64_t)1) << (16 * r))) {
            ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
            return 0;
        }
    }

    /* Memory checks: check total allocated buffer size fits in uint64_t */

    /*
     * B size in section 5 step 1.S
     * Note: we know p * 128 * r < UINT64_MAX because we already checked
     * p * r < SCRYPT_PR_MAX
     */
    Blen = p * 128 * r;
    /*
     * Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would
     * have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.]
     */
    if (Blen > INT_MAX) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }

    /*
     * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
     * This is combined size V, X and T (section 4)
     */
    i = UINT64_MAX / (32 * sizeof(uint32_t));
    if (N + 2 > i / r) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }
    Vlen = 32 * r * (N + 2) * sizeof(uint32_t);

    /* check total allocated size fits in uint64_t */
    if (Blen > UINT64_MAX - Vlen) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }

    /* Check that the maximum memory doesn't exceed a size_t limits */
    if (maxmem > SIZE_MAX)
        maxmem = SIZE_MAX;

    if (Blen + Vlen > maxmem) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }

    /* If no key return to indicate parameters are OK */
    if (key == NULL)
        return 1;

    B = OPENSSL_malloc((size_t)(Blen + Vlen));
    if (B == NULL) {
        ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
        return 0;
    }
    X = (uint32_t *)(B + Blen);
    T = X + 32 * r;
    V = T + 32 * r;
    if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, 1, sha256,
                                  (int)Blen, B, libctx, propq) == 0)
        goto err;

    for (i = 0; i < p; i++)
        scryptROMix(B + 128 * r * i, r, N, X, T, V);

    if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, B, (int)Blen, 1, sha256,
                                  keylen, key, libctx, propq) == 0)
        goto err;
    rv = 1;
 err:
    if (rv == 0)
        ERR_raise(ERR_LIB_EVP, EVP_R_PBKDF2_ERROR);

    OPENSSL_clear_free(B, (size_t)(Blen + Vlen));
    return rv;
}

#endif

Coverage Report

Created: 2025-06-13 06:58

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 2017-2025 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		#include <stdlib.h>
11		#include <stdarg.h>
12		#include <string.h>
13		#include <openssl/evp.h>
14		#include <openssl/kdf.h>
15		#include <openssl/err.h>
16		#include <openssl/core_names.h>
17		#include <openssl/proverr.h>
18		#include "crypto/evp.h"
19		#include "internal/numbers.h"
20		#include "prov/implementations.h"
21		#include "prov/provider_ctx.h"
22		#include "prov/providercommon.h"
23		#include "prov/implementations.h"
24
25		#ifndef OPENSSL_NO_SCRYPT
26
27		static OSSL_FUNC_kdf_newctx_fn kdf_scrypt_new;
28		static OSSL_FUNC_kdf_freectx_fn kdf_scrypt_free;
29		static OSSL_FUNC_kdf_reset_fn kdf_scrypt_reset;
30		static OSSL_FUNC_kdf_derive_fn kdf_scrypt_derive;
31		static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_scrypt_settable_ctx_params;
32		static OSSL_FUNC_kdf_set_ctx_params_fn kdf_scrypt_set_ctx_params;
33		static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_scrypt_gettable_ctx_params;
34		static OSSL_FUNC_kdf_get_ctx_params_fn kdf_scrypt_get_ctx_params;
35
36		static int scrypt_alg(const char *pass, size_t passlen,
37		const unsigned char *salt, size_t saltlen,
38		uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
39		unsigned char key, size_t keylen, EVP_MD sha256,
40		OSSL_LIB_CTX libctx, const char propq);
41
42		typedef struct {
43		OSSL_LIB_CTX *libctx;
44		char *propq;
45		unsigned char *pass;
46		size_t pass_len;
47		unsigned char *salt;
48		size_t salt_len;
49		uint64_t N;
50		uint64_t r, p;
51		uint64_t maxmem_bytes;
52		EVP_MD *sha256;
53		} KDF_SCRYPT;
54
55		static void kdf_scrypt_init(KDF_SCRYPT *ctx);
56
57		static void kdf_scrypt_new(void provctx)
58	0	{
59	0	KDF_SCRYPT *ctx;
60
61	0	if (!ossl_prov_is_running())
62	0	return NULL;
63
64	0	ctx = OPENSSL_zalloc(sizeof(*ctx));
65	0	if (ctx == NULL) {
66	0	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
67	0	return NULL;
68	0	}
69	0	ctx->libctx = PROV_LIBCTX_OF(provctx);
70	0	kdf_scrypt_init(ctx);
71	0	return ctx;
72	0	}
73
74		static void kdf_scrypt_free(void *vctx)
75	30	{
76	30	KDF_SCRYPT ctx = (KDF_SCRYPT )vctx;
77
78	30	if (ctx != NULL) {
79	30	OPENSSL_free(ctx->propq);
80	30	EVP_MD_free(ctx->sha256);
81	30	kdf_scrypt_reset(ctx);
82	30	OPENSSL_free(ctx);
83	30	}
84	30	}
85
86		static void kdf_scrypt_reset(void *vctx)
87	30	{
88	30	KDF_SCRYPT ctx = (KDF_SCRYPT )vctx;
89
90	30	OPENSSL_free(ctx->salt);
91	30	ctx->salt = NULL;
92	30	OPENSSL_clear_free(ctx->pass, ctx->pass_len);
93	30	ctx->pass = NULL;
94	30	kdf_scrypt_init(ctx);
95	30	}
96
97		static void kdf_scrypt_init(KDF_SCRYPT *ctx)
98	60	{
99		/* Default values are the most conservative recommendation given in the
100		* original paper of C. Percival. Derivation uses roughly 1 GiB of memory
101		* for this parameter choice (approx. 128 * r * N * p bytes).
102		*/
103	60	ctx->N = 1 << 20;
104	60	ctx->r = 8;
105	60	ctx->p = 1;
106	60	ctx->maxmem_bytes = 1025 * 1024 * 1024;
107	60	}
108
109		static int scrypt_set_membuf(unsigned char *buffer, size_t buflen,
110		const OSSL_PARAM *p)
111	60	{
112	60	OPENSSL_clear_free(buffer, buflen);
113	60	*buffer = NULL;
114	60	*buflen = 0;
115
116	60	if (p->data_size == 0) {
117	13	if ((*buffer = OPENSSL_malloc(1)) == NULL) {
118	0	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
119	0	return 0;
120	0	}
121	47	} else if (p->data != NULL) {
122	47	if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
123	0	return 0;
124	47	}
125	60	return 1;
126	60	}
127
128		static int set_digest(KDF_SCRYPT *ctx)
129	0	{
130	0	EVP_MD_free(ctx->sha256);
131	0	ctx->sha256 = EVP_MD_fetch(ctx->libctx, "sha256", ctx->propq);
132	0	if (ctx->sha256 == NULL) {
133	0	ERR_raise(ERR_LIB_PROV, PROV_R_UNABLE_TO_LOAD_SHA256);
134	0	return 0;
135	0	}
136	0	return 1;
137	0	}
138
139		static int set_property_query(KDF_SCRYPT ctx, const char propq)
140	0	{
141	0	OPENSSL_free(ctx->propq);
142	0	ctx->propq = NULL;
143	0	if (propq != NULL) {
144	0	ctx->propq = OPENSSL_strdup(propq);
145	0	if (ctx->propq == NULL) {
146	0	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
147	0	return 0;
148	0	}
149	0	}
150	0	return 1;
151	0	}
152
153		static int kdf_scrypt_derive(void vctx, unsigned char key, size_t keylen,
154		const OSSL_PARAM params[])
155	0	{
156	0	KDF_SCRYPT ctx = (KDF_SCRYPT )vctx;
157
158	0	if (!ossl_prov_is_running() \|\| !kdf_scrypt_set_ctx_params(ctx, params))
159	0	return 0;
160
161	0	if (ctx->pass == NULL) {
162	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
163	0	return 0;
164	0	}
165
166	0	if (ctx->salt == NULL) {
167	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
168	0	return 0;
169	0	}
170
171	0	if (ctx->sha256 == NULL && !set_digest(ctx))
172	0	return 0;
173
174	0	return scrypt_alg((char *)ctx->pass, ctx->pass_len, ctx->salt,
175	0	ctx->salt_len, ctx->N, ctx->r, ctx->p,
176	0	ctx->maxmem_bytes, key, keylen, ctx->sha256,
177	0	ctx->libctx, ctx->propq);
178	0	}
179
180		static int is_power_of_two(uint64_t value)
181	0	{
182	0	return (value != 0) && ((value & (value - 1)) == 0);
183	0	}
184
185		static int kdf_scrypt_set_ctx_params(void *vctx, const OSSL_PARAM params[])
186		{
187		const OSSL_PARAM *p;
188		KDF_SCRYPT *ctx = vctx;
189		uint64_t u64_value;
190
191		if (params == NULL)
192		return 1;
193
194		if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL)
195		if (!scrypt_set_membuf(&ctx->pass, &ctx->pass_len, p))
196		return 0;
197
198		if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL)
199		if (!scrypt_set_membuf(&ctx->salt, &ctx->salt_len, p))
200		return 0;
201
202		if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_N))
203		!= NULL) {
204		if (!OSSL_PARAM_get_uint64(p, &u64_value)
205		\|\| u64_value <= 1
206		\|\| !is_power_of_two(u64_value))
207		return 0;
208		ctx->N = u64_value;
209		}
210
211		if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_R))
212		!= NULL) {
213		if (!OSSL_PARAM_get_uint64(p, &u64_value) \|\| u64_value < 1)
214		return 0;
215		ctx->r = u64_value;
216		}
217
218		if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_P))
219		!= NULL) {
220		if (!OSSL_PARAM_get_uint64(p, &u64_value) \|\| u64_value < 1)
221		return 0;
222		ctx->p = u64_value;
223		}
224
225		if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_MAXMEM))
226		!= NULL) {
227		if (!OSSL_PARAM_get_uint64(p, &u64_value) \|\| u64_value < 1)
228		return 0;
229		ctx->maxmem_bytes = u64_value;
230		}
231
232		p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PROPERTIES);
233		if (p != NULL) {
234		if (p->data_type != OSSL_PARAM_UTF8_STRING
235		\|\| !set_property_query(ctx, p->data)
236		\|\| !set_digest(ctx))
237		return 0;
238		}
239		return 1;
240		}
241
242		static const OSSL_PARAM kdf_scrypt_settable_ctx_params(ossl_unused void ctx,
243		ossl_unused void *p_ctx)
244	34	{
245	34	static const OSSL_PARAM known_settable_ctx_params[] = {
246	34	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD, NULL, 0),
247	34	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
248	34	OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_N, NULL),
249	34	OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R, NULL),
250	34	OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P, NULL),
251	34	OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM, NULL),
252	34	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
253	34	OSSL_PARAM_END
254	34	};
255	34	return known_settable_ctx_params;
256	34	}
257
258		static int kdf_scrypt_get_ctx_params(void *vctx, OSSL_PARAM params[])
259	0	{
260	0	OSSL_PARAM *p;
261
262	0	if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
263	0	return OSSL_PARAM_set_size_t(p, SIZE_MAX);
264	0	return -2;
265	0	}
266
267		static const OSSL_PARAM kdf_scrypt_gettable_ctx_params(ossl_unused void ctx,
268		ossl_unused void *p_ctx)
269	0	{
270	0	static const OSSL_PARAM known_gettable_ctx_params[] = {
271	0	OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
272	0	OSSL_PARAM_END
273	0	};
274	0	return known_gettable_ctx_params;
275	0	}
276
277		const OSSL_DISPATCH ossl_kdf_scrypt_functions[] = {
278		{ OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_scrypt_new },
279		{ OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_scrypt_free },
280		{ OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_scrypt_reset },
281		{ OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_scrypt_derive },
282		{ OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
283		(void(*)(void))kdf_scrypt_settable_ctx_params },
284		{ OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_scrypt_set_ctx_params },
285		{ OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
286		(void(*)(void))kdf_scrypt_gettable_ctx_params },
287		{ OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_scrypt_get_ctx_params },
288		{ 0, NULL }
289		};
290
291	0	#define R(a,b) (((a) << (b)) \| ((a) >> (32 - (b))))
292		static void salsa208_word_specification(uint32_t inout[16])
293	0	{
294	0	int i;
295	0	uint32_t x[16];
296
297	0	memcpy(x, inout, sizeof(x));
298	0	for (i = 8; i > 0; i -= 2) {
299	0	x[4] ^= R(x[0] + x[12], 7);
300	0	x[8] ^= R(x[4] + x[0], 9);
301	0	x[12] ^= R(x[8] + x[4], 13);
302	0	x[0] ^= R(x[12] + x[8], 18);
303	0	x[9] ^= R(x[5] + x[1], 7);
304	0	x[13] ^= R(x[9] + x[5], 9);
305	0	x[1] ^= R(x[13] + x[9], 13);
306	0	x[5] ^= R(x[1] + x[13], 18);
307	0	x[14] ^= R(x[10] + x[6], 7);
308	0	x[2] ^= R(x[14] + x[10], 9);
309	0	x[6] ^= R(x[2] + x[14], 13);
310	0	x[10] ^= R(x[6] + x[2], 18);
311	0	x[3] ^= R(x[15] + x[11], 7);
312	0	x[7] ^= R(x[3] + x[15], 9);
313	0	x[11] ^= R(x[7] + x[3], 13);
314	0	x[15] ^= R(x[11] + x[7], 18);
315	0	x[1] ^= R(x[0] + x[3], 7);
316	0	x[2] ^= R(x[1] + x[0], 9);
317	0	x[3] ^= R(x[2] + x[1], 13);
318	0	x[0] ^= R(x[3] + x[2], 18);
319	0	x[6] ^= R(x[5] + x[4], 7);
320	0	x[7] ^= R(x[6] + x[5], 9);
321	0	x[4] ^= R(x[7] + x[6], 13);
322	0	x[5] ^= R(x[4] + x[7], 18);
323	0	x[11] ^= R(x[10] + x[9], 7);
324	0	x[8] ^= R(x[11] + x[10], 9);
325	0	x[9] ^= R(x[8] + x[11], 13);
326	0	x[10] ^= R(x[9] + x[8], 18);
327	0	x[12] ^= R(x[15] + x[14], 7);
328	0	x[13] ^= R(x[12] + x[15], 9);
329	0	x[14] ^= R(x[13] + x[12], 13);
330	0	x[15] ^= R(x[14] + x[13], 18);
331	0	}
332	0	for (i = 0; i < 16; ++i)
333	0	inout[i] += x[i];
334	0	OPENSSL_cleanse(x, sizeof(x));
335	0	}
336
337		static void scryptBlockMix(uint32_t B_, uint32_t B, uint64_t r)
338	0	{
339	0	uint64_t i, j;
340	0	uint32_t X[16], *pB;
341
342	0	memcpy(X, B + (r * 2 - 1) * 16, sizeof(X));
343	0	pB = B;
344	0	for (i = 0; i < r * 2; i++) {
345	0	for (j = 0; j < 16; j++)
346	0	X[j] ^= *pB++;
347	0	salsa208_word_specification(X);
348	0	memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X));
349	0	}
350	0	OPENSSL_cleanse(X, sizeof(X));
351	0	}
352
353		static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N,
354		uint32_t X, uint32_t T, uint32_t *V)
355	0	{
356	0	unsigned char *pB;
357	0	uint32_t *pV;
358	0	uint64_t i, k;
359
360		/* Convert from little endian input */
361	0	for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) {
362	0	pV = pB++;
363	0	pV \|= pB++ << 8;
364	0	pV \|= pB++ << 16;
365	0	pV \|= (uint32_t)pB++ << 24;
366	0	}
367
368	0	for (i = 1; i < N; i++, pV += 32 * r)
369	0	scryptBlockMix(pV, pV - 32 * r, r);
370
371	0	scryptBlockMix(X, V + (N - 1) * 32 * r, r);
372
373	0	for (i = 0; i < N; i++) {
374	0	uint32_t j;
375	0	j = X[16 * (2 * r - 1)] % N;
376	0	pV = V + 32 * r * j;
377	0	for (k = 0; k < 32 * r; k++)
378	0	T[k] = X[k] ^ *pV++;
379	0	scryptBlockMix(X, T, r);
380	0	}
381		/* Convert output to little endian */
382	0	for (i = 0, pB = B; i < 32 * r; i++) {
383	0	uint32_t xtmp = X[i];
384	0	*pB++ = xtmp & 0xff;
385	0	*pB++ = (xtmp >> 8) & 0xff;
386	0	*pB++ = (xtmp >> 16) & 0xff;
387	0	*pB++ = (xtmp >> 24) & 0xff;
388	0	}
389	0	}
390
391		#ifndef SIZE_MAX
392		# define SIZE_MAX ((size_t)-1)
393		#endif
394
395		/*
396		* Maximum power of two that will fit in uint64_t: this should work on
397		* most (all?) platforms.
398		*/
399
400	0	#define LOG2_UINT64_MAX (sizeof(uint64_t) * 8 - 1)
401
402		/*
403		* Maximum value of p * r:
404		* p <= ((2^32-1) * hLen) / MFLen =>
405		* p <= ((2^32-1) * 32) / (128 * r) =>
406		* p * r <= (2^30-1)
407		*/
408
409	0	#define SCRYPT_PR_MAX ((1 << 30) - 1)
410
411		static int scrypt_alg(const char *pass, size_t passlen,
412		const unsigned char *salt, size_t saltlen,
413		uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
414		unsigned char key, size_t keylen, EVP_MD sha256,
415		OSSL_LIB_CTX libctx, const char propq)
416	0	{
417	0	int rv = 0;
418	0	unsigned char *B;
419	0	uint32_t X, V, *T;
420	0	uint64_t i, Blen, Vlen;
421
422		/* Sanity check parameters */
423		/* initial check, r,p must be non zero, N >= 2 and a power of 2 */
424	0	if (r == 0 \|\| p == 0 \|\| N < 2 \|\| (N & (N - 1)))
425	0	return 0;
426		/* Check p * r < SCRYPT_PR_MAX avoiding overflow */
427	0	if (p > SCRYPT_PR_MAX / r) {
428	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
429	0	return 0;
430	0	}
431
432		/*
433		* Need to check N: if 2^(128 * r / 8) overflows limit this is
434		* automatically satisfied since N <= UINT64_MAX.
435		*/
436
437	0	if (16 * r <= LOG2_UINT64_MAX) {
438	0	if (N >= (((uint64_t)1) << (16 * r))) {
439	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
440	0	return 0;
441	0	}
442	0	}
443
444		/* Memory checks: check total allocated buffer size fits in uint64_t */
445
446		/*
447		* B size in section 5 step 1.S
448		* Note: we know p * 128 * r < UINT64_MAX because we already checked
449		* p * r < SCRYPT_PR_MAX
450		*/
451	0	Blen = p * 128 * r;
452		/*
453		* Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would
454		* have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.]
455		*/
456	0	if (Blen > INT_MAX) {
457	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
458	0	return 0;
459	0	}
460
461		/*
462		* Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
463		* This is combined size V, X and T (section 4)
464		*/
465	0	i = UINT64_MAX / (32 * sizeof(uint32_t));
466	0	if (N + 2 > i / r) {
467	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
468	0	return 0;
469	0	}
470	0	Vlen = 32 * r * (N + 2) * sizeof(uint32_t);
471
472		/* check total allocated size fits in uint64_t */
473	0	if (Blen > UINT64_MAX - Vlen) {
474	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
475	0	return 0;
476	0	}
477
478		/* Check that the maximum memory doesn't exceed a size_t limits */
479	0	if (maxmem > SIZE_MAX)
480	0	maxmem = SIZE_MAX;
481
482	0	if (Blen + Vlen > maxmem) {
483	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
484	0	return 0;
485	0	}
486
487		/* If no key return to indicate parameters are OK */
488	0	if (key == NULL)
489	0	return 1;
490
491	0	B = OPENSSL_malloc((size_t)(Blen + Vlen));
492	0	if (B == NULL) {
493	0	ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
494	0	return 0;
495	0	}
496	0	X = (uint32_t *)(B + Blen);
497	0	T = X + 32 * r;
498	0	V = T + 32 * r;
499	0	if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, 1, sha256,
500	0	(int)Blen, B, libctx, propq) == 0)
501	0	goto err;
502
503	0	for (i = 0; i < p; i++)
504	0	scryptROMix(B + 128 * r * i, r, N, X, T, V);
505
506	0	if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, B, (int)Blen, 1, sha256,
507	0	keylen, key, libctx, propq) == 0)
508	0	goto err;
509	0	rv = 1;
510	0	err:
511	0	if (rv == 0)
512	0	ERR_raise(ERR_LIB_EVP, EVP_R_PBKDF2_ERROR);
513
514	0	OPENSSL_clear_free(B, (size_t)(Blen + Vlen));
515	0	return rv;
516	0	}
517
518		#endif