mirror of https://github.com/acidanthera/audk.git
698 lines
17 KiB
C
698 lines
17 KiB
C
/** @file
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RSA Asymmetric Cipher Wrapper Implementation over OpenSSL.
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Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>
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This program and the accompanying materials
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are licensed and made available under the terms and conditions of the BSD License
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which accompanies this distribution. The full text of the license may be found at
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http://opensource.org/licenses/bsd-license.php
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THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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**/
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#include "InternalCryptLib.h"
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#include <openssl/rsa.h>
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#include <openssl/err.h>
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//
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// ASN.1 value for Hash Algorithm ID with the Distringuished Encoding Rules (DER)
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// Refer to Section 9.2 of PKCS#1 v2.1
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//
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CONST UINT8 Asn1IdMd5[] = {
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0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86,
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0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04, 0x10
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};
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CONST UINT8 Asn1IdSha1[] = {
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0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e,
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0x03, 0x02, 0x1a, 0x05, 0x00, 0x04, 0x14
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};
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CONST UINT8 Asn1IdSha256[] = {
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0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86,
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0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05,
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0x00, 0x04, 0x20
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};
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/**
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Allocates and initializes one RSA context for subsequent use.
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@return Pointer to the RSA context that has been initialized.
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If the allocations fails, RsaNew() returns NULL.
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**/
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VOID *
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EFIAPI
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RsaNew (
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VOID
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)
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{
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//
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// Allocates & Initializes RSA Context by OpenSSL RSA_new()
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//
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return (VOID *)RSA_new ();
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}
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/**
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Release the specified RSA context.
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If RsaContext is NULL, then ASSERT().
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@param[in] RsaContext Pointer to the RSA context to be released.
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**/
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VOID
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EFIAPI
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RsaFree (
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IN VOID *RsaContext
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)
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{
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ASSERT (RsaContext != NULL);
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//
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// Free OpenSSL RSA Context
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//
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RSA_free ((RSA *)RsaContext);
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}
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/**
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Sets the tag-designated key component into the established RSA context.
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This function sets the tag-designated RSA key component into the established
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RSA context from the user-specified non-negative integer (octet string format
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represented in RSA PKCS#1).
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If BigNumber is NULL, then the specified key componenet in RSA context is cleared.
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If RsaContext is NULL, then ASSERT().
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@param[in, out] RsaContext Pointer to RSA context being set.
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@param[in] KeyTag Tag of RSA key component being set.
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@param[in] BigNumber Pointer to octet integer buffer.
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If NULL, then the specified key componenet in RSA
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context is cleared.
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@param[in] BnSize Size of big number buffer in bytes.
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If BigNumber is NULL, then it is ignored.
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@retval TRUE RSA key component was set successfully.
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@retval FALSE Invalid RSA key component tag.
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**/
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BOOLEAN
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EFIAPI
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RsaSetKey (
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IN OUT VOID *RsaContext,
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IN RSA_KEY_TAG KeyTag,
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IN CONST UINT8 *BigNumber,
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IN UINTN BnSize
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)
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{
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RSA *RsaKey;
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//
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// ASSERT if RsaContext is NULL
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//
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ASSERT (RsaContext != NULL);
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RsaKey = (RSA *)RsaContext;
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//
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// Set RSA Key Components by converting octet string to OpenSSL BN representation.
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// NOTE: For RSA public key (used in signature verification), only public components
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// (N, e) are needed.
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//
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switch (KeyTag) {
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//
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// RSA Public Modulus (N)
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//
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case RsaKeyN:
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if (RsaKey->n != NULL) {
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BN_free (RsaKey->n);
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}
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RsaKey->n = NULL;
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if (BigNumber == NULL) {
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break;
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}
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RsaKey->n = BN_bin2bn (BigNumber, (UINT32) BnSize, RsaKey->n);
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break;
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//
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// RSA Public Exponent (e)
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//
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case RsaKeyE:
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if (RsaKey->e != NULL) {
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BN_free (RsaKey->e);
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}
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RsaKey->e = NULL;
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if (BigNumber == NULL) {
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break;
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}
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RsaKey->e = BN_bin2bn (BigNumber, (UINT32) BnSize, RsaKey->e);
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break;
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//
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// RSA Private Exponent (d)
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//
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case RsaKeyD:
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if (RsaKey->d != NULL) {
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BN_free (RsaKey->d);
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}
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RsaKey->d = NULL;
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if (BigNumber == NULL) {
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break;
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}
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RsaKey->d = BN_bin2bn (BigNumber, (UINT32) BnSize, RsaKey->d);
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break;
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//
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// RSA Secret Prime Factor of Modulus (p)
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//
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case RsaKeyP:
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if (RsaKey->p != NULL) {
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BN_free (RsaKey->p);
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}
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RsaKey->p = NULL;
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if (BigNumber == NULL) {
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break;
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}
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RsaKey->p = BN_bin2bn (BigNumber, (UINT32) BnSize, RsaKey->p);
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break;
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//
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// RSA Secret Prime Factor of Modules (q)
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//
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case RsaKeyQ:
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if (RsaKey->q != NULL) {
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BN_free (RsaKey->q);
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}
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RsaKey->q = NULL;
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if (BigNumber == NULL) {
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break;
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}
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RsaKey->q = BN_bin2bn (BigNumber, (UINT32) BnSize, RsaKey->q);
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break;
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//
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// p's CRT Exponent (== d mod (p - 1))
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//
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case RsaKeyDp:
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if (RsaKey->dmp1 != NULL) {
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BN_free (RsaKey->dmp1);
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}
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RsaKey->dmp1 = NULL;
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if (BigNumber == NULL) {
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break;
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}
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RsaKey->dmp1 = BN_bin2bn (BigNumber, (UINT32) BnSize, RsaKey->dmp1);
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break;
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//
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// q's CRT Exponent (== d mod (q - 1))
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//
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case RsaKeyDq:
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if (RsaKey->dmq1 != NULL) {
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BN_free (RsaKey->dmq1);
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}
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RsaKey->dmq1 = NULL;
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if (BigNumber == NULL) {
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break;
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}
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RsaKey->dmq1 = BN_bin2bn (BigNumber, (UINT32) BnSize, RsaKey->dmq1);
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break;
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//
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// The CRT Coefficient (== 1/q mod p)
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//
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case RsaKeyQInv:
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if (RsaKey->iqmp != NULL) {
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BN_free (RsaKey->iqmp);
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}
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RsaKey->iqmp = NULL;
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if (BigNumber == NULL) {
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break;
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}
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RsaKey->iqmp = BN_bin2bn (BigNumber, (UINT32) BnSize, RsaKey->iqmp);
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break;
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default:
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return FALSE;
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}
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return TRUE;
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}
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/**
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Gets the tag-designated RSA key component from the established RSA context.
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This function retrieves the tag-designated RSA key component from the
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established RSA context as a non-negative integer (octet string format
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represented in RSA PKCS#1).
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If specified key component has not been set or has been cleared, then returned
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BnSize is set to 0.
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If the BigNumber buffer is too small to hold the contents of the key, FALSE
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is returned and BnSize is set to the required buffer size to obtain the key.
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If RsaContext is NULL, then ASSERT().
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If BnSize is NULL, then ASSERT().
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If BnSize is large enough but BigNumber is NULL, then ASSERT().
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@param[in, out] RsaContext Pointer to RSA context being set.
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@param[in] KeyTag Tag of RSA key component being set.
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@param[out] BigNumber Pointer to octet integer buffer.
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@param[in, out] BnSize On input, the size of big number buffer in bytes.
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On output, the size of data returned in big number buffer in bytes.
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@retval TRUE RSA key component was retrieved successfully.
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@retval FALSE Invalid RSA key component tag.
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@retval FALSE BnSize is too small.
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**/
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BOOLEAN
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EFIAPI
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RsaGetKey (
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IN OUT VOID *RsaContext,
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IN RSA_KEY_TAG KeyTag,
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OUT UINT8 *BigNumber,
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IN OUT UINTN *BnSize
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)
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{
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RSA *RsaKey;
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BIGNUM *BnKey;
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UINTN Size;
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ASSERT (RsaContext != NULL);
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ASSERT (BnSize != NULL);
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RsaKey = (RSA *) RsaContext;
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Size = *BnSize;
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*BnSize = 0;
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switch (KeyTag) {
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//
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// RSA Public Modulus (N)
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//
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case RsaKeyN:
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if (RsaKey->n == NULL) {
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return TRUE;
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}
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BnKey = RsaKey->n;
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break;
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//
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// RSA Public Exponent (e)
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//
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case RsaKeyE:
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if (RsaKey->e == NULL) {
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return TRUE;
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}
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BnKey = RsaKey->e;
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break;
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//
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// RSA Private Exponent (d)
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//
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case RsaKeyD:
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if (RsaKey->d == NULL) {
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return TRUE;
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}
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BnKey = RsaKey->d;
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break;
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//
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// RSA Secret Prime Factor of Modulus (p)
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//
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case RsaKeyP:
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if (RsaKey->p == NULL) {
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return TRUE;
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}
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BnKey = RsaKey->p;
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break;
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//
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// RSA Secret Prime Factor of Modules (q)
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//
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case RsaKeyQ:
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if (RsaKey->q == NULL) {
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return TRUE;
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}
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BnKey = RsaKey->q;
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break;
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//
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// p's CRT Exponent (== d mod (p - 1))
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//
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case RsaKeyDp:
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if (RsaKey->dmp1 == NULL) {
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return TRUE;
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}
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BnKey = RsaKey->dmp1;
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break;
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//
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// q's CRT Exponent (== d mod (q - 1))
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//
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case RsaKeyDq:
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if (RsaKey->dmq1 == NULL) {
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return TRUE;
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}
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BnKey = RsaKey->dmq1;
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break;
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//
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// The CRT Coefficient (== 1/q mod p)
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//
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case RsaKeyQInv:
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if (RsaKey->iqmp == NULL) {
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return TRUE;
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}
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BnKey = RsaKey->iqmp;
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break;
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default:
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return FALSE;
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}
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*BnSize = Size;
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Size = BN_num_bytes (BnKey);
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if (*BnSize < Size) {
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*BnSize = Size;
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return FALSE;
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}
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ASSERT (BigNumber != NULL);
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*BnSize = BN_bn2bin (BnKey, BigNumber) ;
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return TRUE;
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}
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/**
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Generates RSA key components.
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This function generates RSA key components. It takes RSA public exponent E and
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length in bits of RSA modulus N as input, and generates all key components.
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If PublicExponent is NULL, the default RSA public exponent (0x10001) will be used.
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Before this function can be invoked, pseudorandom number generator must be correctly
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initialized by RandomSeed().
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If RsaContext is NULL, then ASSERT().
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@param[in, out] RsaContext Pointer to RSA context being set.
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@param[in] ModulusLength Length of RSA modulus N in bits.
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@param[in] PublicExponent Pointer to RSA public exponent.
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@param[in] PublicExponentSize Size of RSA public exponent buffer in bytes.
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@retval TRUE RSA key component was generated successfully.
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@retval FALSE Invalid RSA key component tag.
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**/
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BOOLEAN
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EFIAPI
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RsaGenerateKey (
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IN OUT VOID *RsaContext,
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IN UINTN ModulusLength,
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IN CONST UINT8 *PublicExponent,
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IN UINTN PublicExponentSize
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)
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{
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BIGNUM *KeyE;
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BOOLEAN RetVal;
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ASSERT (RsaContext != NULL);
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KeyE = BN_new ();
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if (PublicExponent == NULL) {
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BN_set_word (KeyE, 0x10001);
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} else {
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BN_bin2bn (PublicExponent, (UINT32) PublicExponentSize, KeyE);
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}
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RetVal = FALSE;
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if (RSA_generate_key_ex ((RSA *) RsaContext, (UINT32) ModulusLength, KeyE, NULL) == 1) {
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RetVal = TRUE;
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}
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BN_free (KeyE);
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return RetVal;
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}
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/**
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Validates key components of RSA context.
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This function validates key compoents of RSA context in following aspects:
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- Whether p is a prime
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- Whether q is a prime
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- Whether n = p * q
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- Whether d*e = 1 mod lcm(p-1,q-1)
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If RsaContext is NULL, then ASSERT().
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@param[in] RsaContext Pointer to RSA context to check.
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@retval TRUE RSA key components are valid.
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@retval FALSE RSA key components are not valid.
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**/
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BOOLEAN
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EFIAPI
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RsaCheckKey (
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IN VOID *RsaContext
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)
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{
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UINTN Reason;
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ASSERT (RsaContext != NULL);
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if (RSA_check_key ((RSA *) RsaContext) != 1) {
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Reason = ERR_GET_REASON (ERR_peek_last_error ());
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if (Reason == RSA_R_P_NOT_PRIME ||
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Reason == RSA_R_Q_NOT_PRIME ||
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Reason == RSA_R_N_DOES_NOT_EQUAL_P_Q ||
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Reason == RSA_R_D_E_NOT_CONGRUENT_TO_1) {
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return FALSE;
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}
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}
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return TRUE;
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}
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/**
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Performs the PKCS1-v1_5 encoding methods defined in RSA PKCS #1.
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@param Message Message buffer to be encoded.
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@param MessageSize Size of message buffer in bytes.
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@param DigestInfo Pointer to buffer of digest info for output.
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@return Size of DigestInfo in bytes.
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**/
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UINTN
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DigestInfoEncoding (
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IN CONST UINT8 *Message,
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IN UINTN MessageSize,
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OUT UINT8 *DigestInfo
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)
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{
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CONST UINT8 *HashDer;
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UINTN DerSize;
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ASSERT (Message != NULL);
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ASSERT (DigestInfo != NULL);
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//
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// The original message length is used to determine the hash algorithm since
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// message is digest value hashed by the specified algorithm.
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//
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switch (MessageSize) {
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case MD5_DIGEST_SIZE:
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HashDer = Asn1IdMd5;
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DerSize = sizeof (Asn1IdMd5);
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break;
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case SHA1_DIGEST_SIZE:
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HashDer = Asn1IdSha1;
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DerSize = sizeof (Asn1IdSha1);
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break;
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case SHA256_DIGEST_SIZE:
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HashDer = Asn1IdSha256;
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DerSize = sizeof (Asn1IdSha256);
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break;
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default:
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return FALSE;
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}
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CopyMem (DigestInfo, HashDer, DerSize);
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CopyMem (DigestInfo + DerSize, Message, MessageSize);
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return (DerSize + MessageSize);
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}
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/**
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Carries out the RSA-SSA signature generation with EMSA-PKCS1-v1_5 encoding scheme.
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This function carries out the RSA-SSA signature generation with EMSA-PKCS1-v1_5 encoding scheme defined in
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RSA PKCS#1.
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If the Signature buffer is too small to hold the contents of signature, FALSE
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is returned and SigSize is set to the required buffer size to obtain the signature.
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If RsaContext is NULL, then ASSERT().
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If MessageHash is NULL, then ASSERT().
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If HashSize is not equal to the size of MD5, SHA-1, SHA-256, SHA-224, SHA-512 or SHA-384 digest, then ASSERT().
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If SigSize is large enough but Signature is NULL, then ASSERT().
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@param[in] RsaContext Pointer to RSA context for signature generation.
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@param[in] MessageHash Pointer to octet message hash to be signed.
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@param[in] HashSize Size of the message hash in bytes.
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@param[out] Signature Pointer to buffer to receive RSA PKCS1-v1_5 signature.
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@param[in, out] SigSize On input, the size of Signature buffer in bytes.
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On output, the size of data returned in Signature buffer in bytes.
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@retval TRUE Signature successfully generated in PKCS1-v1_5.
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@retval FALSE Signature generation failed.
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@retval FALSE SigSize is too small.
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**/
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BOOLEAN
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EFIAPI
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RsaPkcs1Sign (
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IN VOID *RsaContext,
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IN CONST UINT8 *MessageHash,
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IN UINTN HashSize,
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OUT UINT8 *Signature,
|
|
IN OUT UINTN *SigSize
|
|
)
|
|
{
|
|
RSA *Rsa;
|
|
UINTN Size;
|
|
INTN ReturnVal;
|
|
|
|
ASSERT (RsaContext != NULL);
|
|
ASSERT (MessageHash != NULL);
|
|
ASSERT ((HashSize == MD5_DIGEST_SIZE) ||
|
|
(HashSize == SHA1_DIGEST_SIZE) ||
|
|
(HashSize == SHA256_DIGEST_SIZE));
|
|
|
|
Rsa = (RSA *) RsaContext;
|
|
Size = BN_num_bytes (Rsa->n);
|
|
|
|
if (*SigSize < Size) {
|
|
*SigSize = Size;
|
|
return FALSE;
|
|
}
|
|
|
|
ASSERT (Signature != NULL);
|
|
|
|
Size = DigestInfoEncoding (MessageHash, HashSize, Signature);
|
|
|
|
ReturnVal = RSA_private_encrypt (
|
|
(UINT32) Size,
|
|
Signature,
|
|
Signature,
|
|
Rsa,
|
|
RSA_PKCS1_PADDING
|
|
);
|
|
|
|
if (ReturnVal < (INTN) Size) {
|
|
return FALSE;
|
|
}
|
|
|
|
*SigSize = (UINTN)ReturnVal;
|
|
return TRUE;
|
|
}
|
|
|
|
/**
|
|
Verifies the RSA-SSA signature with EMSA-PKCS1-v1_5 encoding scheme defined in
|
|
RSA PKCS#1.
|
|
|
|
If RsaContext is NULL, then ASSERT().
|
|
If MessageHash is NULL, then ASSERT().
|
|
If Signature is NULL, then ASSERT().
|
|
If HashSize is not equal to the size of MD5, SHA-1, SHA-256, SHA-224, SHA-512 or SHA-384 digest, then ASSERT().
|
|
|
|
@param[in] RsaContext Pointer to RSA context for signature verification.
|
|
@param[in] MessageHash Pointer to octet message hash to be checked.
|
|
@param[in] HashSize Size of the message hash in bytes.
|
|
@param[in] Signature Pointer to RSA PKCS1-v1_5 signature to be verified.
|
|
@param[in] SigSize Size of signature in bytes.
|
|
|
|
@retval TRUE Valid signature encoded in PKCS1-v1_5.
|
|
@retval FALSE Invalid signature or invalid RSA context.
|
|
|
|
**/
|
|
BOOLEAN
|
|
EFIAPI
|
|
RsaPkcs1Verify (
|
|
IN VOID *RsaContext,
|
|
IN CONST UINT8 *MessageHash,
|
|
IN UINTN HashSize,
|
|
IN UINT8 *Signature,
|
|
IN UINTN SigSize
|
|
)
|
|
{
|
|
INTN Length;
|
|
|
|
//
|
|
// ASSERT if RsaContext, MessageHash or Signature is NULL
|
|
//
|
|
ASSERT (RsaContext != NULL);
|
|
ASSERT (MessageHash != NULL);
|
|
ASSERT (Signature != NULL);
|
|
|
|
//
|
|
// ASSERT if unsupported hash size:
|
|
// Only MD5, SHA-1 or SHA-256 digest size is supported
|
|
//
|
|
ASSERT ((HashSize == MD5_DIGEST_SIZE) || (HashSize == SHA1_DIGEST_SIZE) ||
|
|
(HashSize == SHA256_DIGEST_SIZE));
|
|
|
|
//
|
|
// RSA PKCS#1 Signature Decoding using OpenSSL RSA Decryption with Public Key
|
|
//
|
|
Length = RSA_public_decrypt (
|
|
(UINT32) SigSize,
|
|
Signature,
|
|
Signature,
|
|
RsaContext,
|
|
RSA_PKCS1_PADDING
|
|
);
|
|
|
|
//
|
|
// Invalid RSA Key or PKCS#1 Padding Checking Failed (if Length < 0)
|
|
// NOTE: Length should be the addition of HashSize and some DER value.
|
|
// Ignore more strict length checking here.
|
|
//
|
|
if (Length < (INTN) HashSize) {
|
|
return FALSE;
|
|
}
|
|
|
|
//
|
|
// Validate the MessageHash and Decoded Signature
|
|
// NOTE: The decoded Signature should be the DER encoding of the DigestInfo value
|
|
// DigestInfo ::= SEQUENCE {
|
|
// digestAlgorithm AlgorithmIdentifier
|
|
// digest OCTET STRING
|
|
// }
|
|
// Then Memory Comparing should skip the DER value of the underlying SEQUENCE
|
|
// type and AlgorithmIdentifier.
|
|
//
|
|
if (CompareMem (MessageHash, Signature + Length - HashSize, HashSize) == 0) {
|
|
//
|
|
// Valid RSA PKCS#1 Signature
|
|
//
|
|
return TRUE;
|
|
} else {
|
|
//
|
|
// Failed to verification
|
|
//
|
|
return FALSE;
|
|
}
|
|
}
|