crypto/kdf/tls1_prf.c - third_party/openssl - Git at Google

 /*
  * Copyright 2016 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 <stdio.h>
 #include "internal/cryptlib.h"
 #include <openssl/kdf.h>
 #include <openssl/evp.h>
 #include "internal/evp_int.h"

 static int tls1_prf_alg(const EVP_MD *md,
                         const unsigned char *sec, size_t slen,
                         const unsigned char *seed, size_t seed_len,
                         unsigned char *out, size_t olen);

 #define TLS1_PRF_MAXBUF 1024

 /* TLS KDF pkey context structure */

 typedef struct {
     /* Digest to use for PRF */
     const EVP_MD *md;
     /* Secret value to use for PRF */
     unsigned char *sec;
     size_t seclen;
     /* Buffer of concatenated seed data */
     unsigned char seed[TLS1_PRF_MAXBUF];
     size_t seedlen;
 } TLS1_PRF_PKEY_CTX;

 static int pkey_tls1_prf_init(EVP_PKEY_CTX *ctx)
 {
     TLS1_PRF_PKEY_CTX *kctx;

     kctx = OPENSSL_zalloc(sizeof(*kctx));
     if (kctx == NULL)
         return 0;
     ctx->data = kctx;

     return 1;
 }

 static void pkey_tls1_prf_cleanup(EVP_PKEY_CTX *ctx)
 {
     TLS1_PRF_PKEY_CTX *kctx = ctx->data;
     OPENSSL_clear_free(kctx->sec, kctx->seclen);
     OPENSSL_cleanse(kctx->seed, kctx->seedlen);
     OPENSSL_free(kctx);
 }

 static int pkey_tls1_prf_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
 {
     TLS1_PRF_PKEY_CTX *kctx = ctx->data;
     switch (type) {
     case EVP_PKEY_CTRL_TLS_MD:
         kctx->md = p2;
         return 1;

     case EVP_PKEY_CTRL_TLS_SECRET:
         if (p1 < 0)
             return 0;
         if (kctx->sec != NULL)
             OPENSSL_clear_free(kctx->sec, kctx->seclen);
         OPENSSL_cleanse(kctx->seed, kctx->seedlen);
         kctx->seedlen = 0;
         kctx->sec = OPENSSL_memdup(p2, p1);
         if (kctx->sec == NULL)
             return 0;
         kctx->seclen  = p1;
         return 1;

     case EVP_PKEY_CTRL_TLS_SEED:
         if (p1 == 0 || p2 == NULL)
             return 1;
         if (p1 < 0 || p1 > (int)(TLS1_PRF_MAXBUF - kctx->seedlen))
             return 0;
         memcpy(kctx->seed + kctx->seedlen, p2, p1);
         kctx->seedlen += p1;
         return 1;

     default:
         return -2;

     }
 }

 static int pkey_tls1_prf_ctrl_str(EVP_PKEY_CTX *ctx,
                                   const char *type, const char *value)
 {
     if (value == NULL) {
         KDFerr(KDF_F_PKEY_TLS1_PRF_CTRL_STR, KDF_R_VALUE_MISSING);
         return 0;
     }
     if (strcmp(type, "md") == 0) {
         TLS1_PRF_PKEY_CTX *kctx = ctx->data;

         const EVP_MD *md = EVP_get_digestbyname(value);
         if (md == NULL) {
             KDFerr(KDF_F_PKEY_TLS1_PRF_CTRL_STR, KDF_R_INVALID_DIGEST);
             return 0;
         }
         kctx->md = md;
         return 1;
     }
     if (strcmp(type, "secret") == 0)
         return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_TLS_SECRET, value);
     if (strcmp(type, "hexsecret") == 0)
         return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_TLS_SECRET, value);
     if (strcmp(type, "seed") == 0)
         return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_TLS_SEED, value);
     if (strcmp(type, "hexseed") == 0)
         return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_TLS_SEED, value);
     return -2;
 }

 static int pkey_tls1_prf_derive(EVP_PKEY_CTX *ctx, unsigned char *key,
                                 size_t *keylen)
 {
     TLS1_PRF_PKEY_CTX *kctx = ctx->data;
     if (kctx->md == NULL || kctx->sec == NULL || kctx->seedlen == 0) {
         KDFerr(KDF_F_PKEY_TLS1_PRF_DERIVE, KDF_R_MISSING_PARAMETER);
         return 0;
     }
     return tls1_prf_alg(kctx->md, kctx->sec, kctx->seclen,
                         kctx->seed, kctx->seedlen,
                         key, *keylen);
 }

 const EVP_PKEY_METHOD tls1_prf_pkey_meth = {
     EVP_PKEY_TLS1_PRF,
     0,
     pkey_tls1_prf_init,
     0,
     pkey_tls1_prf_cleanup,

     0, 0,
     0, 0,

     0,
     0,

     0,
     0,

     0, 0,

     0, 0, 0, 0,

     0, 0,

     0, 0,

     0,
     pkey_tls1_prf_derive,
     pkey_tls1_prf_ctrl,
     pkey_tls1_prf_ctrl_str
 };

 static int tls1_prf_P_hash(const EVP_MD *md,
                            const unsigned char *sec, size_t sec_len,
                            const unsigned char *seed, size_t seed_len,
                            unsigned char *out, size_t olen)
 {
     int chunk;
     EVP_MD_CTX *ctx = NULL, *ctx_tmp = NULL, *ctx_init = NULL;
     EVP_PKEY *mac_key = NULL;
     unsigned char A1[EVP_MAX_MD_SIZE];
     size_t A1_len;
     int ret = 0;

     chunk = EVP_MD_size(md);
     OPENSSL_assert(chunk >= 0);

     ctx = EVP_MD_CTX_new();
     ctx_tmp = EVP_MD_CTX_new();
     ctx_init = EVP_MD_CTX_new();
     if (ctx == NULL || ctx_tmp == NULL || ctx_init == NULL)
         goto err;
     EVP_MD_CTX_set_flags(ctx_init, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
     mac_key = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, sec, sec_len);
     if (mac_key == NULL)
         goto err;
     if (!EVP_DigestSignInit(ctx_init, NULL, md, NULL, mac_key))
         goto err;
     if (!EVP_MD_CTX_copy_ex(ctx, ctx_init))
         goto err;
     if (seed != NULL && !EVP_DigestSignUpdate(ctx, seed, seed_len))
         goto err;
     if (!EVP_DigestSignFinal(ctx, A1, &A1_len))
         goto err;

     for (;;) {
         /* Reinit mac contexts */
         if (!EVP_MD_CTX_copy_ex(ctx, ctx_init))
             goto err;
         if (!EVP_DigestSignUpdate(ctx, A1, A1_len))
             goto err;
         if (olen > (size_t)chunk && !EVP_MD_CTX_copy_ex(ctx_tmp, ctx))
             goto err;
         if (seed && !EVP_DigestSignUpdate(ctx, seed, seed_len))
             goto err;

         if (olen > (size_t)chunk) {
             size_t mac_len;
             if (!EVP_DigestSignFinal(ctx, out, &mac_len))
                 goto err;
             out += mac_len;
             olen -= mac_len;
             /* calc the next A1 value */
             if (!EVP_DigestSignFinal(ctx_tmp, A1, &A1_len))
                 goto err;
         } else {                /* last one */

             if (!EVP_DigestSignFinal(ctx, A1, &A1_len))
                 goto err;
             memcpy(out, A1, olen);
             break;
         }
     }
     ret = 1;
  err:
     EVP_PKEY_free(mac_key);
     EVP_MD_CTX_free(ctx);
     EVP_MD_CTX_free(ctx_tmp);
     EVP_MD_CTX_free(ctx_init);
     OPENSSL_cleanse(A1, sizeof(A1));
     return ret;
 }

 static int tls1_prf_alg(const EVP_MD *md,
                         const unsigned char *sec, size_t slen,
                         const unsigned char *seed, size_t seed_len,
                         unsigned char *out, size_t olen)
 {

     if (EVP_MD_type(md) == NID_md5_sha1) {
         size_t i;
         unsigned char *tmp;
         if (!tls1_prf_P_hash(EVP_md5(), sec, slen/2 + (slen & 1),
                          seed, seed_len, out, olen))
             return 0;

         tmp = OPENSSL_malloc(olen);
         if (tmp == NULL)
             return 0;
         if (!tls1_prf_P_hash(EVP_sha1(), sec + slen/2, slen/2 + (slen & 1),
                          seed, seed_len, tmp, olen)) {
             OPENSSL_clear_free(tmp, olen);
             return 0;
         }
         for (i = 0; i < olen; i++)
             out[i] ^= tmp[i];
         OPENSSL_clear_free(tmp, olen);
         return 1;
     }
     if (!tls1_prf_P_hash(md, sec, slen, seed, seed_len, out, olen))
         return 0;

     return 1;
 }
	/*
	* Copyright 2016 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 <stdio.h>
	#include "internal/cryptlib.h"
	#include <openssl/kdf.h>
	#include <openssl/evp.h>
	#include "internal/evp_int.h"

	static int tls1_prf_alg(const EVP_MD *md,
	const unsigned char *sec, size_t slen,
	const unsigned char *seed, size_t seed_len,
	unsigned char *out, size_t olen);

	#define TLS1_PRF_MAXBUF 1024

	/* TLS KDF pkey context structure */

	typedef struct {
	/* Digest to use for PRF */
	const EVP_MD *md;
	/* Secret value to use for PRF */
	unsigned char *sec;
	size_t seclen;
	/* Buffer of concatenated seed data */
	unsigned char seed[TLS1_PRF_MAXBUF];
	size_t seedlen;
	} TLS1_PRF_PKEY_CTX;

	static int pkey_tls1_prf_init(EVP_PKEY_CTX *ctx)
	{
	TLS1_PRF_PKEY_CTX *kctx;

	kctx = OPENSSL_zalloc(sizeof(*kctx));
	if (kctx == NULL)
	return 0;
	ctx->data = kctx;

	return 1;
	}

	static void pkey_tls1_prf_cleanup(EVP_PKEY_CTX *ctx)
	{
	TLS1_PRF_PKEY_CTX *kctx = ctx->data;
	OPENSSL_clear_free(kctx->sec, kctx->seclen);
	OPENSSL_cleanse(kctx->seed, kctx->seedlen);
	OPENSSL_free(kctx);
	}

	static int pkey_tls1_prf_ctrl(EVP_PKEY_CTX ctx, int type, int p1, void p2)
	{
	TLS1_PRF_PKEY_CTX *kctx = ctx->data;
	switch (type) {
	case EVP_PKEY_CTRL_TLS_MD:
	kctx->md = p2;
	return 1;

	case EVP_PKEY_CTRL_TLS_SECRET:
	if (p1 < 0)
	return 0;
	if (kctx->sec != NULL)
	OPENSSL_clear_free(kctx->sec, kctx->seclen);
	OPENSSL_cleanse(kctx->seed, kctx->seedlen);
	kctx->seedlen = 0;
	kctx->sec = OPENSSL_memdup(p2, p1);
	if (kctx->sec == NULL)
	return 0;
	kctx->seclen = p1;
	return 1;

	case EVP_PKEY_CTRL_TLS_SEED:
	if (p1 == 0 \|\| p2 == NULL)
	return 1;
	if (p1 < 0 \|\| p1 > (int)(TLS1_PRF_MAXBUF - kctx->seedlen))
	return 0;
	memcpy(kctx->seed + kctx->seedlen, p2, p1);
	kctx->seedlen += p1;
	return 1;

	default:
	return -2;

	}
	}

	static int pkey_tls1_prf_ctrl_str(EVP_PKEY_CTX *ctx,
	const char type, const char value)
	{
	if (value == NULL) {
	KDFerr(KDF_F_PKEY_TLS1_PRF_CTRL_STR, KDF_R_VALUE_MISSING);
	return 0;
	}
	if (strcmp(type, "md") == 0) {
	TLS1_PRF_PKEY_CTX *kctx = ctx->data;

	const EVP_MD *md = EVP_get_digestbyname(value);
	if (md == NULL) {
	KDFerr(KDF_F_PKEY_TLS1_PRF_CTRL_STR, KDF_R_INVALID_DIGEST);
	return 0;
	}
	kctx->md = md;
	return 1;
	}
	if (strcmp(type, "secret") == 0)
	return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_TLS_SECRET, value);
	if (strcmp(type, "hexsecret") == 0)
	return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_TLS_SECRET, value);
	if (strcmp(type, "seed") == 0)
	return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_TLS_SEED, value);
	if (strcmp(type, "hexseed") == 0)
	return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_TLS_SEED, value);
	return -2;
	}

	static int pkey_tls1_prf_derive(EVP_PKEY_CTX ctx, unsigned char key,
	size_t *keylen)
	{
	TLS1_PRF_PKEY_CTX *kctx = ctx->data;
	if (kctx->md == NULL \|\| kctx->sec == NULL \|\| kctx->seedlen == 0) {
	KDFerr(KDF_F_PKEY_TLS1_PRF_DERIVE, KDF_R_MISSING_PARAMETER);
	return 0;
	}
	return tls1_prf_alg(kctx->md, kctx->sec, kctx->seclen,
	kctx->seed, kctx->seedlen,
	key, *keylen);
	}

	const EVP_PKEY_METHOD tls1_prf_pkey_meth = {
	EVP_PKEY_TLS1_PRF,
	0,
	pkey_tls1_prf_init,
	0,
	pkey_tls1_prf_cleanup,

	0, 0,
	0, 0,

	0,
	0,

	0,
	0,

	0, 0,

	0, 0, 0, 0,

	0, 0,

	0, 0,

	0,
	pkey_tls1_prf_derive,
	pkey_tls1_prf_ctrl,
	pkey_tls1_prf_ctrl_str
	};

	static int tls1_prf_P_hash(const EVP_MD *md,
	const unsigned char *sec, size_t sec_len,
	const unsigned char *seed, size_t seed_len,
	unsigned char *out, size_t olen)
	{
	int chunk;
	EVP_MD_CTX ctx = NULL, ctx_tmp = NULL, *ctx_init = NULL;
	EVP_PKEY *mac_key = NULL;
	unsigned char A1[EVP_MAX_MD_SIZE];
	size_t A1_len;
	int ret = 0;

	chunk = EVP_MD_size(md);
	OPENSSL_assert(chunk >= 0);

	ctx = EVP_MD_CTX_new();
	ctx_tmp = EVP_MD_CTX_new();
	ctx_init = EVP_MD_CTX_new();
	if (ctx == NULL \|\| ctx_tmp == NULL \|\| ctx_init == NULL)
	goto err;
	EVP_MD_CTX_set_flags(ctx_init, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
	mac_key = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, sec, sec_len);
	if (mac_key == NULL)
	goto err;
	if (!EVP_DigestSignInit(ctx_init, NULL, md, NULL, mac_key))
	goto err;
	if (!EVP_MD_CTX_copy_ex(ctx, ctx_init))
	goto err;
	if (seed != NULL && !EVP_DigestSignUpdate(ctx, seed, seed_len))
	goto err;
	if (!EVP_DigestSignFinal(ctx, A1, &A1_len))
	goto err;

	for (;;) {
	/* Reinit mac contexts */
	if (!EVP_MD_CTX_copy_ex(ctx, ctx_init))
	goto err;
	if (!EVP_DigestSignUpdate(ctx, A1, A1_len))
	goto err;
	if (olen > (size_t)chunk && !EVP_MD_CTX_copy_ex(ctx_tmp, ctx))
	goto err;
	if (seed && !EVP_DigestSignUpdate(ctx, seed, seed_len))
	goto err;

	if (olen > (size_t)chunk) {
	size_t mac_len;
	if (!EVP_DigestSignFinal(ctx, out, &mac_len))
	goto err;
	out += mac_len;
	olen -= mac_len;
	/* calc the next A1 value */
	if (!EVP_DigestSignFinal(ctx_tmp, A1, &A1_len))
	goto err;
	} else { /* last one */

	if (!EVP_DigestSignFinal(ctx, A1, &A1_len))
	goto err;
	memcpy(out, A1, olen);
	break;
	}
	}
	ret = 1;
	err:
	EVP_PKEY_free(mac_key);
	EVP_MD_CTX_free(ctx);
	EVP_MD_CTX_free(ctx_tmp);
	EVP_MD_CTX_free(ctx_init);
	OPENSSL_cleanse(A1, sizeof(A1));
	return ret;
	}

	static int tls1_prf_alg(const EVP_MD *md,
	const unsigned char *sec, size_t slen,
	const unsigned char *seed, size_t seed_len,
	unsigned char *out, size_t olen)
	{

	if (EVP_MD_type(md) == NID_md5_sha1) {
	size_t i;
	unsigned char *tmp;
	if (!tls1_prf_P_hash(EVP_md5(), sec, slen/2 + (slen & 1),
	seed, seed_len, out, olen))
	return 0;

	tmp = OPENSSL_malloc(olen);
	if (tmp == NULL)
	return 0;
	if (!tls1_prf_P_hash(EVP_sha1(), sec + slen/2, slen/2 + (slen & 1),
	seed, seed_len, tmp, olen)) {
	OPENSSL_clear_free(tmp, olen);
	return 0;
	}
	for (i = 0; i < olen; i++)
	out[i] ^= tmp[i];
	OPENSSL_clear_free(tmp, olen);
	return 1;
	}
	if (!tls1_prf_P_hash(md, sec, slen, seed, seed_len, out, olen))
	return 0;

	return 1;
	}