Re: [PATCH v1 1/1] CryptoPkg: BaseCryptLib: Add RSA PSS verify support

["Yao, Jiewen" <jiewen.yao@intel.com>]

Hi Sachin
May I know why you hardcode PSS salt length to be RSA_PSS_SALTLEN_AUTO ?

Thank you
Yao Jiewen


> -----Original Message-----
> From: Agrawal, Sachin <sachin.agrawal@intel.com>
> Sent: Tuesday, April 20, 2021 10:02 AM
> To: devel@edk2.groups.io
> Cc: Yao, Jiewen <jiewen.yao@intel.com>; Wang, Jian J <jian.j.wang@intel.com>;
> Lu, XiaoyuX <xiaoyux.lu@intel.com>; Jiang, Guomin <guomin.jiang@intel.com>;
> Agrawal, Sachin <sachin.agrawal@intel.com>
> Subject: [PATCH v1 1/1] CryptoPkg: BaseCryptLib: Add RSA PSS verify support
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3314
> 
> This patch uses Openssl's EVP API's to perform RSASSA-PSS verification
> of a binary blob.
> 
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Xiaoyu Lu <xiaoyux.lu@intel.com>
> Cc: Guomin Jiang <guomin.jiang@intel.com>
> 
> Signed-off-by: Sachin Agrawal <sachin.agrawal@intel.com>
> ---
>  CryptoPkg/Library/BaseCryptLib/Pk/CryptRsaPss.c     | 139
> ++++++++++++++++++++
>  CryptoPkg/Library/BaseCryptLib/Pk/CryptRsaPssNull.c |  43 ++++++
>  CryptoPkg/Include/Library/BaseCryptLib.h            |  27 ++++
>  CryptoPkg/Library/BaseCryptLib/BaseCryptLib.inf     |   1 +
>  CryptoPkg/Library/BaseCryptLib/PeiCryptLib.inf      |   1 +
>  CryptoPkg/Library/BaseCryptLib/RuntimeCryptLib.inf  |   1 +
>  CryptoPkg/Library/BaseCryptLib/SmmCryptLib.inf      |   1 +
>  7 files changed, 213 insertions(+)
> 
> diff --git a/CryptoPkg/Library/BaseCryptLib/Pk/CryptRsaPss.c
> b/CryptoPkg/Library/BaseCryptLib/Pk/CryptRsaPss.c
> new file mode 100644
> index 000000000000..acf5eb689cd8
> --- /dev/null
> +++ b/CryptoPkg/Library/BaseCryptLib/Pk/CryptRsaPss.c
> @@ -0,0 +1,139 @@
> +/** @file
> +  RSA Asymmetric Cipher Wrapper Implementation over OpenSSL.
> +
> +  This file implements following APIs which provide basic capabilities for RSA:
> +  1) RsaPssVerify
> +
> +Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include "InternalCryptLib.h"
> +
> +#include <openssl/bn.h>
> +#include <openssl/rsa.h>
> +#include <openssl/objects.h>
> +#include <openssl/evp.h>
> +
> +
> +/**
> +  Retrieve a pointer to EVP message digest object.
> +
> +  @param[in]  DigestLen   Length of the message digest.
> +
> +**/
> +static
> +EVP_MD*
> +GetEvpMD (
> +  IN UINT16 DigestLen
> +  )
> +{
> +  switch (DigestLen){
> +    case SHA256_DIGEST_SIZE:
> +      return EVP_sha256();
> +      break;
> +    case SHA384_DIGEST_SIZE:
> +      return EVP_sha384();
> +      break;
> +    case SHA512_DIGEST_SIZE:
> +      return EVP_sha512();
> +      break;
> +    default:
> +      return NULL;
> +  }
> +}
> +
> +
> +/**
> +  Verifies the RSA signature with RSASSA-PSS signature scheme defined in RFC
> 8017.
> +  Implementation determines salt length automatically from the signature
> encoding.
> +  Mask generation function is the same as the message digest algorithm.
> +
> +  @param[in]  RsaContext      Pointer to RSA context for signature verification.
> +  @param[in]  Message         Pointer to octet message to be verified.
> +  @param[in]  MsgSize         Size of the message in bytes.
> +  @param[in]  Signature       Pointer to RSASSA-PSS signature to be verified.
> +  @param[in]  SigSize         Size of signature in bytes.
> +  @param[in]  DigestLen       Length of digest for RSA operation.
> +
> +  @retval  TRUE   Valid signature encoded in RSASSA-PSS.
> +  @retval  FALSE  Invalid signature or invalid RSA context.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +RsaPssVerify (
> +  IN  VOID         *RsaContext,
> +  IN  CONST UINT8  *Message,
> +  IN  UINTN        MsgSize,
> +  IN  CONST UINT8  *Signature,
> +  IN  UINTN        SigSize,
> +  IN  UINT16       DigestLen
> +  )
> +{
> +  BOOLEAN Result;
> +  EVP_PKEY *pEvpRsaKey = NULL;
> +  EVP_MD_CTX *pEvpVerifyCtx = NULL;
> +  EVP_PKEY_CTX *pKeyCtx = NULL;
> +  CONST EVP_MD  *HashAlg = NULL;
> +
> +  if (RsaContext == NULL) {
> +    return FALSE;
> +  }
> +  if (Message == NULL || MsgSize == 0 || MsgSize > INT_MAX) {
> +    return FALSE;
> +  }
> +  if (Signature == NULL || SigSize == 0 || SigSize > INT_MAX) {
> +    return FALSE;
> +  }
> +
> +  HashAlg = GetEvpMD(DigestLen);
> +
> +  if (HashAlg == NULL) {
> +    return FALSE;
> +  }
> +
> +  pEvpRsaKey = EVP_PKEY_new();
> +  if (pEvpRsaKey == NULL) {
> +    goto _Exit;
> +  }
> +
> +  EVP_PKEY_set1_RSA(pEvpRsaKey, RsaContext);
> +
> +  pEvpVerifyCtx = EVP_MD_CTX_create();
> +  if (pEvpVerifyCtx == NULL) {
> +    goto _Exit;
> +  }
> +
> +  Result = EVP_DigestVerifyInit(pEvpVerifyCtx, &pKeyCtx, HashAlg, NULL,
> pEvpRsaKey) > 0;
> +  if (pKeyCtx == NULL) {
> +    goto _Exit;
> +  }
> +
> +  if (Result) {
> +    Result = EVP_PKEY_CTX_set_rsa_padding(pKeyCtx,
> RSA_PKCS1_PSS_PADDING) > 0;
> +  }
> +  if (Result) {
> +    Result = EVP_PKEY_CTX_set_rsa_pss_saltlen(pKeyCtx,
> RSA_PSS_SALTLEN_AUTO) > 0;
> +  }
> +  if (Result) {
> +    Result = EVP_PKEY_CTX_set_rsa_mgf1_md(pKeyCtx, HashAlg) > 0;
> +  }
> +  if (Result) {
> +    Result = EVP_DigestVerifyUpdate(pEvpVerifyCtx, Message,
> (UINT32)MsgSize) > 0;
> +  }
> +  if (Result) {
> +    Result = EVP_DigestVerifyFinal(pEvpVerifyCtx, Signature, (UINT32)SigSize) > 0;
> +  }
> +
> +_Exit :
> +  if (pEvpRsaKey) {
> +    EVP_PKEY_free(pEvpRsaKey);
> +  }
> +  if (pEvpVerifyCtx) {
> +    EVP_MD_CTX_destroy(pEvpVerifyCtx);
> +  }
> +
> +  return Result;
> +}
> diff --git a/CryptoPkg/Library/BaseCryptLib/Pk/CryptRsaPssNull.c
> b/CryptoPkg/Library/BaseCryptLib/Pk/CryptRsaPssNull.c
> new file mode 100644
> index 000000000000..8d84b4c1426c
> --- /dev/null
> +++ b/CryptoPkg/Library/BaseCryptLib/Pk/CryptRsaPssNull.c
> @@ -0,0 +1,43 @@
> +/** @file
> +  RSA-PSS Asymmetric Cipher Wrapper Implementation over OpenSSL.
> +
> +  This file does not provide real capabilities for following APIs in RSA handling:
> +  1) RsaPssVerify
> +
> +Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include "InternalCryptLib.h"
> +
> +/**
> +  Verifies the RSA signature with RSASSA-PSS signature scheme defined in RFC
> 8017.
> +  Implementation determines salt length automatically from the signature
> encoding.
> +  Mask generation function is the same as the message digest algorithm.
> +
> +  @param[in]  RsaContext      Pointer to RSA context for signature verification.
> +  @param[in]  Message         Pointer to octet message to be verified.
> +  @param[in]  MsgSize         Size of the message in bytes.
> +  @param[in]  Signature       Pointer to RSASSA-PSS signature to be verified.
> +  @param[in]  SigSize         Size of signature in bytes.
> +  @param[in]  DigestLen       Length of digest for RSA operation.
> +
> +  @retval  TRUE   Valid signature encoded in RSASSA-PSS.
> +  @retval  FALSE  Invalid signature or invalid RSA context.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +RsaPssVerify (
> +  IN  VOID         *RsaContext,
> +  IN  CONST UINT8  *Message,
> +  IN  UINTN        MsgSize,
> +  IN  CONST UINT8  *Signature,
> +  IN  UINTN        SigSize,
> +  IN  UINT16       DigestLen
> +  )
> +{
> +  ASSERT (FALSE);
> +  return FALSE;
> +}
> diff --git a/CryptoPkg/Include/Library/BaseCryptLib.h
> b/CryptoPkg/Include/Library/BaseCryptLib.h
> index 496121e6a4ed..36d560b8d691 100644
> --- a/CryptoPkg/Include/Library/BaseCryptLib.h
> +++ b/CryptoPkg/Include/Library/BaseCryptLib.h
> @@ -1363,6 +1363,33 @@ RsaPkcs1Verify (
>    IN  UINTN        SigSize
>    );
> 
> +/**
> +  Verifies the RSA signature with RSASSA-PSS signature scheme defined in RFC
> 8017.
> +  Implementation determines salt length automatically from the signature
> encoding.
> +  Mask generation function is the same as the message digest algorithm.
> +
> +  @param[in]  RsaContext      Pointer to RSA context for signature verification.
> +  @param[in]  Message         Pointer to octet message to be verified.
> +  @param[in]  MsgSize         Size of the message in bytes.
> +  @param[in]  Signature       Pointer to RSASSA-PSS signature to be verified.
> +  @param[in]  SigSize         Size of signature in bytes.
> +  @param[in]  DigestLen       Length of digest for RSA operation.
> +
> +  @retval  TRUE   Valid signature encoded in RSASSA-PSS.
> +  @retval  FALSE  Invalid signature or invalid RSA context.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +RsaPssVerify (
> +  IN  VOID         *RsaContext,
> +  IN  CONST UINT8  *Message,
> +  IN  UINTN        MsgSize,
> +  IN  CONST UINT8  *Signature,
> +  IN  UINTN        SigSize,
> +  IN  UINT16       DigestLen
> +  );
> +
>  /**
>    Retrieve the RSA Private Key from the password-protected PEM key data.
>