Added DRBG_HMAC & DRBG_HASH + Added defaults for setting DRBG for...

LIBS=../../libcrypto

SOURCE[../../libcrypto]=\

        randfile.c rand_lib.c rand_err.c rand_egd.c \

        rand_win.c rand_unix.c rand_vms.c drbg_lib.c drbg_ctr.c

        rand_win.c rand_unix.c rand_vms.c drbg_lib.c drbg_ctr.c \

        drbg_hash.c drbg_hmac.c

#include <openssl/err.h>

#include <openssl/rand.h>

#include "internal/thread_once.h"

#include "internal/thread_once.h"

#include "rand_lcl.h"

/*

 * Implementation of NIST SP 800-90A CTR DRBG.

 */

static void inc_128(RAND_DRBG_CTR *ctr)

{

    int i;

/*

 * Copyright 2011-2018 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <assert.h>

#include <stdlib.h>

#include <string.h>

#include <openssl/crypto.h>

#include <openssl/err.h>

#include <openssl/rand.h>

#include "internal/thread_once.h"

#include "rand_lcl.h"

/* 440 bits from SP800-90Ar1 10.1 table 2 */

#define HASH_PRNG_SMALL_SEEDLEN   (440/8)

/* Determine what seedlen to use based on the block length */

#define MAX_BLOCKLEN_USING_SMALL_SEEDLEN (256/8)

#define INBYTE_IGNORE ((unsigned char)0xFF)

/*

 * SP800-90Ar1 10.3.1 Derivation function using a Hash Function (Hash_df).

 * The input string used is composed of:

 *    inbyte - An optional leading byte (ignore if equal to INBYTE_IGNORE)

 *    in - input string 1 (A Non NULL value).

 *    in2 - optional input string (Can be NULL).

 *    in3 - optional input string (Can be NULL).

 *    These are concatenated as part of the DigestUpdate process.

 */

static int hash_df(RAND_DRBG *drbg, unsigned char *out,

                   const unsigned char inbyte,

                   const unsigned char *in, size_t inlen,

                   const unsigned char *in2, size_t in2len,

                   const unsigned char *in3, size_t in3len)

{

    RAND_DRBG_HASH *hash = &drbg->data.hash;

    EVP_MD_CTX *ctx = hash->ctx;

    unsigned char *vtmp = hash->vtmp;

    /* tmp = counter || num_bits_returned || [inbyte] */

    unsigned char tmp[1 + 4 + 1];

    int tmp_sz = 0;

    size_t outlen = drbg->seedlen;

    size_t num_bits_returned = outlen * 8;

    /*

     * No need to check outlen size here, as the standard only ever needs

     * seedlen bytes which is always less than the maximum permitted.

     */

    /* (Step 3) counter = 1 (tmp[0] is the 8 bit counter) */

    tmp[tmp_sz++] = 1;

    /* tmp[1..4] is the fixed 32 bit no_of_bits_to_return */

    tmp[tmp_sz++] = (unsigned char)((num_bits_returned >> 24) & 0xff);

    tmp[tmp_sz++] = (unsigned char)((num_bits_returned >> 16) & 0xff);

    tmp[tmp_sz++] = (unsigned char)((num_bits_returned >> 8) & 0xff);

    tmp[tmp_sz++] = (unsigned char)(num_bits_returned & 0xff);

    /* Tack the additional input byte onto the end of tmp if it exists */

    if (inbyte != INBYTE_IGNORE)

        tmp[tmp_sz++] = inbyte;

    /* (Step 4) */

    for (;;) {

        /*

         * (Step 4.1) out = out || Hash(tmp || in || [in2] || [in3])

         *            (where tmp = counter || num_bits_returned || [inbyte])

         */

        if (!(EVP_DigestInit_ex(ctx, hash->md, NULL)

                && EVP_DigestUpdate(ctx, tmp, tmp_sz)

                && EVP_DigestUpdate(ctx, in, inlen)

                && (in2 == NULL || EVP_DigestUpdate(ctx, in2, in2len))

                && (in3 == NULL || EVP_DigestUpdate(ctx, in3, in3len))))

            return 0;

        if (outlen < hash->blocklen) {

            if (!EVP_DigestFinal(ctx, vtmp, NULL))

                return 0;

            memcpy(out, vtmp, outlen);

            OPENSSL_cleanse(vtmp, hash->blocklen);

            break;

        } else if(!EVP_DigestFinal(ctx, out, NULL)) {

            return 0;

        }

        outlen -= hash->blocklen;

        if (outlen == 0)

            break;

        /* (Step 4.2) counter++ */

        tmp[0]++;

        out += hash->blocklen;

    }

    return 1;

}

/* Helper function that just passes 2 input parameters to hash_df() */

static int hash_df1(RAND_DRBG *drbg, unsigned char *out,

                    const unsigned char in_byte,

                    const unsigned char *in1, size_t in1len)

{

    return hash_df(drbg, out, in_byte, in1, in1len, NULL, 0, NULL, 0);

}

/*

 * Add 2 byte buffers together. The first elements in each buffer are the top

 * most bytes. The result is stored in the dst buffer.

 * The final carry is ignored i.e: dst =  (dst + in) mod (2^seedlen_bits).

 * where dst size is drbg->seedlen, and inlen <= drbg->seedlen.

 */

static int add_bytes(RAND_DRBG *drbg, unsigned char *dst,

                     unsigned char *in, size_t inlen)

{

    size_t i;

    int result;

    const unsigned char *add;

    unsigned char carry = 0, *d;

    assert(drbg->seedlen >= 1 && inlen >= 1 && inlen <= drbg->seedlen);

    d = &dst[drbg->seedlen - 1];

    add = &in[inlen - 1];

    for (i = inlen; i > 0; i--, d--, add--) {

        result = *d + *add + carry;

        carry = (unsigned char)(result >> 8);

        *d = (unsigned char)(result & 0xff);

    }

    if (carry != 0) {

        /* Add the carry to the top of the dst if inlen is not the same size */

        for (i = drbg->seedlen - inlen; i > 0; --i, d--) {

            *d += 1;     /* Carry can only be 1 */

            if (*d != 0) /* exit if carry doesnt propagate to the next byte */

                break;

        }

    }

    return 1;

}

/* V = (V + Hash(inbyte || V  || [additional_input]) mod (2^seedlen) */

static int add_hash_to_v(RAND_DRBG *drbg, unsigned char inbyte,

                         const unsigned char *adin, size_t adinlen)

{

    RAND_DRBG_HASH *hash = &drbg->data.hash;

    EVP_MD_CTX *ctx = hash->ctx;

    return EVP_DigestInit_ex(ctx, hash->md, NULL)

           && EVP_DigestUpdate(ctx, &inbyte, 1)

           && EVP_DigestUpdate(ctx, hash->V, drbg->seedlen)

           && (adin == NULL || EVP_DigestUpdate(ctx, adin, adinlen))

           && EVP_DigestFinal(ctx, hash->vtmp, NULL)

           && add_bytes(drbg, hash->V, hash->vtmp, hash->blocklen);

}

/*

 * The Hashgen() as listed in SP800-90Ar1 10.1.1.4 Hash_DRBG_Generate_Process.

 *

 * drbg contains the current value of V.

 * outlen is the requested number of bytes.

 * out is a buffer to return the generated bits.

 *

 * The algorithm to generate the bits is:

 *     data = V

 *     w = NULL

 *     for (i = 1 to m) {

 *        W = W || Hash(data)

 *        data = (data + 1) mod (2^seedlen)

 *     }

 *     out = Leftmost(W, outlen)

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int hash_gen(RAND_DRBG *drbg, unsigned char *out, size_t outlen)

{

    RAND_DRBG_HASH *hash = &drbg->data.hash;

    unsigned char one = 1;

    if (outlen == 0)

        return 1;

    memcpy(hash->vtmp, hash->V, drbg->seedlen);

    for(;;) {

        if (!EVP_DigestInit_ex(hash->ctx, hash->md, NULL)

                || !EVP_DigestUpdate(hash->ctx, hash->vtmp, drbg->seedlen))

            return 0;

        if (outlen < hash->blocklen) {

            if (!EVP_DigestFinal(hash->ctx, hash->vtmp, NULL))

                return 0;

            memcpy(out, hash->vtmp, outlen);

            return 1;

        } else {

            if (!EVP_DigestFinal(hash->ctx, out, NULL))

                return 0;

            outlen -= hash->blocklen;

            if (outlen == 0)

                break;

            out += hash->blocklen;

        }

        add_bytes(drbg, hash->vtmp, &one, 1);

    }

    return 1;

}

/*

 * SP800-90Ar1 10.1.1.2 Hash_DRBG_Instantiate_Process:

 *

 * ent is entropy input obtained from a randomness source of length ent_len.

 * nonce is a string of bytes of length nonce_len.

 * pstr is a personalization string received from an application. May be NULL.

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int drbg_hash_instantiate(RAND_DRBG *drbg,

                                 const unsigned char *ent, size_t ent_len,

                                 const unsigned char *nonce, size_t nonce_len,

                                 const unsigned char *pstr, size_t pstr_len)

{

    RAND_DRBG_HASH *hash = &drbg->data.hash;

    /* (Step 1-3) V = Hash_df(entropy||nonce||pers, seedlen) */

    return hash_df(drbg, hash->V, INBYTE_IGNORE,

                   ent, ent_len, nonce, nonce_len, pstr, pstr_len)

           /* (Step 4) C = Hash_df(0x00||V, seedlen) */

           && hash_df1(drbg, hash->C, 0x00, hash->V, drbg->seedlen);

}

/*

 * SP800-90Ar1 10.1.1.3 Hash_DRBG_Reseed_Process:

 *

 * ent is entropy input bytes obtained from a randomness source.

 * addin is additional input received from an application. May be NULL.

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int drbg_hash_reseed(RAND_DRBG *drbg,

                            const unsigned char *ent, size_t ent_len,

                            const unsigned char *adin, size_t adin_len)

{

    RAND_DRBG_HASH *hash = &drbg->data.hash;

    /* (Step 1-2) V = Hash_df(0x01 || V || entropy_input || additional_input)*/

    /* V about to be updated so use C as output instead */

    if (!hash_df(drbg, hash->C, 0x01, hash->V, drbg->seedlen, ent, ent_len,

                 adin, adin_len))

        return 0;

    memcpy(hash->V, hash->C, drbg->seedlen);

    /* (Step 4) C = Hash_df(0x00||V, seedlen) */

    return hash_df1(drbg, hash->C, 0x00, hash->V, drbg->seedlen);

}

/*

 * SP800-90Ar1 10.1.1.4 Hash_DRBG_Generate_Process:

 *

 * Generates pseudo random bytes using the drbg.

 * out is a buffer to fill with outlen bytes of pseudo random data.

 * addin is additional input received from an application. May be NULL.

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int drbg_hash_generate(RAND_DRBG *drbg,

                              unsigned char *out, size_t outlen,

                              const unsigned char *adin, size_t adin_len)

{

    RAND_DRBG_HASH *hash = &drbg->data.hash;

    unsigned char counter[4];

    int reseed_counter = drbg->reseed_gen_counter;

    counter[0] = (unsigned char)((reseed_counter >> 24) & 0xff);

    counter[1] = (unsigned char)((reseed_counter >> 16) & 0xff);

    counter[2] = (unsigned char)((reseed_counter >> 8) & 0xff);

    counter[3] = (unsigned char)(reseed_counter & 0xff);

    return (adin == NULL

           /* (Step 2) if adin != NULL then V = V + Hash(0x02||V||adin) */

                || adin_len == 0

                || add_hash_to_v(drbg, 0x02, adin, adin_len))

           /* (Step 3) Hashgen(outlen, V) */

           && hash_gen(drbg, out, outlen)

           /* (Step 4/5) H = V = (V + Hash(0x03||V) mod (2^seedlen_bits) */

           && add_hash_to_v(drbg, 0x03, NULL, 0)

           /* (Step 5) V = (V + H + C + reseed_counter) mod (2^seedlen_bits) */

           /* V = (V + C) mod (2^seedlen_bits) */

           && add_bytes(drbg, hash->V, hash->C, drbg->seedlen)

           /* V = (V + reseed_counter) mod (2^seedlen_bits) */

           && add_bytes(drbg, hash->V, counter, 4);

}

static int drbg_hash_uninstantiate(RAND_DRBG *drbg)

{

    EVP_MD_CTX_free(drbg->data.hash.ctx);

    OPENSSL_cleanse(&drbg->data.hash, sizeof(drbg->data.hash));

    return 1;

}

static RAND_DRBG_METHOD drbg_hash_meth = {

    drbg_hash_instantiate,

    drbg_hash_reseed,

    drbg_hash_generate,

    drbg_hash_uninstantiate

};

int drbg_hash_init(RAND_DRBG *drbg)

{

    const EVP_MD *md;

    RAND_DRBG_HASH *hash = &drbg->data.hash;

    /* Any approved digest is allowed */

    md = EVP_get_digestbynid(drbg->type);

    if (md == NULL)

        return 0;

    drbg->meth = &drbg_hash_meth;

    hash->md = md;

    if (hash->ctx == NULL) {

        hash->ctx = EVP_MD_CTX_new();

        if (hash->ctx == NULL)

            return 0;

    }

    /* These are taken from SP 800-90 10.1 Table 2 */

    hash->blocklen = EVP_MD_size(md);

    /* See SP800-57 Part1 Rev4 5.6.1 Table 3 */

    drbg->strength = 64 * (hash->blocklen >> 3);

    if (drbg->strength > 256)

        drbg->strength = 256;

    if (hash->blocklen > MAX_BLOCKLEN_USING_SMALL_SEEDLEN)

        drbg->seedlen = HASH_PRNG_MAX_SEEDLEN;

    else

        drbg->seedlen = HASH_PRNG_SMALL_SEEDLEN;

    drbg->min_entropylen = drbg->strength / 8;

    drbg->max_entropylen = DRBG_MINMAX_FACTOR * drbg->min_entropylen;

    drbg->min_noncelen = drbg->min_entropylen / 2;

    drbg->max_noncelen = DRBG_MINMAX_FACTOR * drbg->min_noncelen;

    drbg->max_perslen = DRBG_MAX_LENGTH;

    drbg->max_adinlen = DRBG_MAX_LENGTH;

    /* Maximum number of bits per request = 2^19  = 2^16 bytes */

    drbg->max_request = 1 << 16;

    return 1;

}

/*

 * Copyright 2011-2018 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <stdlib.h>

#include <string.h>

#include <openssl/crypto.h>

#include <openssl/err.h>

#include <openssl/rand.h>

#include "internal/thread_once.h"

#include "rand_lcl.h"

/*

 * Called twice by SP800-90Ar1 10.1.2.2 HMAC_DRBG_Update_Process.

 *

 * hmac is an object that holds the input/output Key and Value (K and V).

 * inbyte is 0x00 on the first call and 0x01 on the second call.

 * in1, in2, in3 are optional inputs that can be NULL.

 * in1len, in2len, in3len are the lengths of the input buffers.

 *

 * The returned K,V is:

 *   hmac->K = HMAC(hmac->K, hmac->V || inbyte || [in1] || [in2] || [in3])

 *   hmac->V = HMAC(hmac->K, hmac->V)

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int do_hmac(RAND_DRBG_HMAC *hmac, unsigned char inbyte,

                   const unsigned char *in1, size_t in1len,

                   const unsigned char *in2, size_t in2len,

                   const unsigned char *in3, size_t in3len)

{

    HMAC_CTX *ctx = hmac->ctx;

    return HMAC_Init_ex(ctx, hmac->K, hmac->blocklen, hmac->md, NULL)

           /* K = HMAC(K, V || inbyte || [in1] || [in2] || [in3]) */

           && HMAC_Update(ctx, hmac->V, hmac->blocklen)

           && HMAC_Update(ctx, &inbyte, 1)

           && (in1 == NULL || in1len == 0 || HMAC_Update(ctx, in1, in1len))

           && (in2 == NULL || in2len == 0 || HMAC_Update(ctx, in2, in2len))

           && (in3 == NULL || in3len == 0 || HMAC_Update(ctx, in3, in3len))

           && HMAC_Final(ctx, hmac->K, NULL)

           /* V = HMAC(K, V) */

           && HMAC_Init_ex(ctx, hmac->K, hmac->blocklen, hmac->md, NULL)

           && HMAC_Update(ctx, hmac->V, hmac->blocklen)

           && HMAC_Final(ctx, hmac->V, NULL);

}

/*

 * SP800-90Ar1 10.1.2.2 HMAC_DRBG_Update_Process

 *

 *

 * Updates the drbg objects Key(K) and Value(V) using the following algorithm:

 *   K,V = do_hmac(hmac, 0, in1, in2, in3)

 *   if (any input is not NULL)

 *     K,V = do_hmac(hmac, 1, in1, in2, in3)

 *

 * where in1, in2, in3 are optional input buffers that can be NULL.

 *       in1len, in2len, in3len are the lengths of the input buffers.

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int drbg_hmac_update(RAND_DRBG *drbg,

                            const unsigned char *in1, size_t in1len,

                            const unsigned char *in2, size_t in2len,

                            const unsigned char *in3, size_t in3len)

{

    RAND_DRBG_HMAC *hmac = &drbg->data.hmac;

    /* (Steps 1-2) K = HMAC(K, V||0x00||provided_data). V = HMAC(K,V) */

    if (!do_hmac(hmac, 0x00, in1, in1len, in2, in2len, in3, in3len))

        return 0;

    /* (Step 3) If provided_data == NULL then return (K,V) */

    if (in1len == 0 && in2len == 0 && in3len == 0)

        return 1;

    /* (Steps 4-5) K = HMAC(K, V||0x01||provided_data). V = HMAC(K,V) */

    return do_hmac(hmac, 0x01, in1, in1len, in2, in2len, in3, in3len);

}

/*

 * SP800-90Ar1 10.1.2.3 HMAC_DRBG_Instantiate_Process:

 *

 * This sets the drbg Key (K) to all zeros, and Value (V) to all 1's.

 * and then calls (K,V) = drbg_hmac_update() with input parameters:

 *   ent = entropy data (Can be NULL) of length ent_len.

 *   nonce = nonce data (Can be NULL) of length nonce_len.

 *   pstr = personalization data (Can be NULL) of length pstr_len.

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int drbg_hmac_instantiate(RAND_DRBG *drbg,

                                 const unsigned char *ent, size_t ent_len,

                                 const unsigned char *nonce, size_t nonce_len,

                                 const unsigned char *pstr, size_t pstr_len)

{

    RAND_DRBG_HMAC *hmac = &drbg->data.hmac;

    /* (Step 2) Key = 0x00 00...00 */

    memset(hmac->K, 0x00, hmac->blocklen);

    /* (Step 3) V = 0x01 01...01 */

    memset(hmac->V, 0x01, hmac->blocklen);

    /* (Step 4) (K,V) = HMAC_DRBG_Update(entropy||nonce||pers string, K, V) */

    return drbg_hmac_update(drbg, ent, ent_len, nonce, nonce_len, pstr,

                            pstr_len);

}

/*

 * SP800-90Ar1 10.1.2.4 HMAC_DRBG_Reseed_Process:

 *

 * Reseeds the drbg's Key (K) and Value (V) by calling

 * (K,V) = drbg_hmac_update() with the following input parameters:

 *   ent = entropy input data (Can be NULL) of length ent_len.

 *   adin = additional input data (Can be NULL) of length adin_len.

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int drbg_hmac_reseed(RAND_DRBG *drbg,

                            const unsigned char *ent, size_t ent_len,

                            const unsigned char *adin, size_t adin_len)

{

    /* (Step 2) (K,V) = HMAC_DRBG_Update(entropy||additional_input, K, V) */

    return drbg_hmac_update(drbg, ent, ent_len, adin, adin_len, NULL, 0);

}

/*

 * SP800-90Ar1 10.1.2.5 HMAC_DRBG_Generate_Process:

 *

 * Generates pseudo random bytes and updates the internal K,V for the drbg.

 * out is a buffer to fill with outlen bytes of pseudo random data.

 * adin is an additional_input string of size adin_len that may be NULL.

 *

 * Returns zero if an error occurs otherwise it returns 1.

 */

static int drbg_hmac_generate(RAND_DRBG *drbg,

                              unsigned char *out, size_t outlen,

                              const unsigned char *adin, size_t adin_len)

{

    RAND_DRBG_HMAC *hmac = &drbg->data.hmac;

    HMAC_CTX *ctx = hmac->ctx;

    const unsigned char *temp = hmac->V;

    /* (Step 2) if adin != NULL then (K,V) = HMAC_DRBG_Update(adin, K, V) */

    if (adin != NULL

            && adin_len > 0

            && !drbg_hmac_update(drbg, adin, adin_len, NULL, 0, NULL, 0))

        return 0;

    /*

     * (Steps 3-5) temp = NULL

     *             while (len(temp) < outlen) {

     *                 V = HMAC(K, V)

     *                 temp = temp || V

     *             }

     */

    for (;;) {

        if (!HMAC_Init_ex(ctx, hmac->K, hmac->blocklen, hmac->md, NULL)

                || !HMAC_Update(ctx, temp, hmac->blocklen))

            return 0;

        if (outlen > hmac->blocklen) {

            if (!HMAC_Final(ctx, out, NULL))

                return 0;

            temp = out;

        } else {

            if (!HMAC_Final(ctx, hmac->V, NULL))

                return 0;

            memcpy(out, hmac->V, outlen);

            break;

        }

        out += hmac->blocklen;

        outlen -= hmac->blocklen;

    }

    /* (Step 6) (K,V) = HMAC_DRBG_Update(adin, K, V) */

    if (!drbg_hmac_update(drbg, adin, adin_len, NULL, 0, NULL, 0))

        return 0;

    return 1;

}

static int drbg_hmac_uninstantiate(RAND_DRBG *drbg)

{

    HMAC_CTX_free(drbg->data.hmac.ctx);

    OPENSSL_cleanse(&drbg->data.hmac, sizeof(drbg->data.hmac));

    return 1;

}

static RAND_DRBG_METHOD drbg_hmac_meth = {

    drbg_hmac_instantiate,

    drbg_hmac_reseed,

    drbg_hmac_generate,

    drbg_hmac_uninstantiate

};

int drbg_hmac_init(RAND_DRBG *drbg)

{

    const EVP_MD *md = NULL;

    RAND_DRBG_HMAC *hmac = &drbg->data.hmac;

    /* Any approved digest is allowed - assume we pass digest (not NID_hmac*) */

    md = EVP_get_digestbynid(drbg->type);

    if (md == NULL)

        return 0;

    drbg->meth = &drbg_hmac_meth;

    if (hmac->ctx == NULL) {

        hmac->ctx = HMAC_CTX_new();

        if (hmac->ctx == NULL)

            return 0;

    }

    /* These are taken from SP 800-90 10.1 Table 2 */

    hmac->md = md;

    hmac->blocklen = EVP_MD_size(md);

    /* See SP800-57 Part1 Rev4 5.6.1 Table 3 */

    drbg->strength = 64 * (int)(hmac->blocklen >> 3);

    if (drbg->strength > 256)

        drbg->strength = 256;

    drbg->seedlen = hmac->blocklen;

    drbg->min_entropylen = drbg->strength / 8;

    drbg->max_entropylen = DRBG_MINMAX_FACTOR * drbg->min_entropylen;

    drbg->min_noncelen = drbg->min_entropylen / 2;

    drbg->max_noncelen = DRBG_MINMAX_FACTOR * drbg->min_noncelen;

    drbg->max_perslen = DRBG_MAX_LENGTH;

    drbg->max_adinlen = DRBG_MAX_LENGTH;

    /* Maximum number of bits per request = 2^19 = 2^16 bytes*/

    drbg->max_request = 1 << 16;

    return 1;

}