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|
/***************************************************************************
* Copyright (c) 2024 Microsoft Corporation
* Copyright (c) 2025-present Eclipse ThreadX Contributors
*
* This program and the accompanying materials are made available under the
* terms of the MIT License which is available at
* https://opensource.org/licenses/MIT.
*
* SPDX-License-Identifier: MIT
**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** NetX Crypto Component */
/** */
/** RSA public-key encryption algorithm */
/** */
/**************************************************************************/
/**************************************************************************/
#include "nx_crypto_rsa.h"
#include "nx_crypto_huge_number.h"
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _nx_crypto_rsa_operation PORTABLE C */
/* 6.4.3 */
/* AUTHOR */
/* */
/* Timothy Stapko, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function performs an RSA encryption/decryption operation - */
/* for RSA the operation is the same but with different values */
/* for the exponent. */
/* */
/* The output is always the same length as the modulus. */
/* */
/* If NULL is passed for the scratch buffer pointer, an internal */
/* scratch buffer is used. */
/* */
/* INPUT */
/* */
/* exponent RSA exponent */
/* exponent_length Length of exponent in bytes */
/* modulus RSA modulus */
/* modulus_length Length of modulus in bytes */
/* p RSA prime p */
/* p_length Length of p in bytes */
/* q RSA prime q */
/* q_length Length of q in bytes */
/* input Input data */
/* input_length Length of input in bytes */
/* output Output buffer */
/* scratch_buf_ptr Pointer to scratch buffer */
/* scratch_buf_length Length of scratch buffer */
/* */
/* OUTPUT */
/* */
/* status Completion status */
/* */
/* CALLS */
/* */
/* _nx_crypto_huge_number_setup Setup huge number */
/* _nx_crypto_huge_number_crt_power_modulus */
/* Raise a huge number for CRT */
/* _nx_crypto_huge_number_mont_power_modulus */
/* Raise a huge number for */
/* montgomery reduction */
/* _nx_crypto_huge_number_extract Extract huge number */
/* */
/* CALLED BY */
/* */
/* _nx_crypto_method_rsa_operation Handle RSA operation */
/* */
/**************************************************************************/
NX_CRYPTO_KEEP UINT _nx_crypto_rsa_operation(const UCHAR *exponent, UINT exponent_length, const UCHAR *modulus, UINT modulus_length,
const UCHAR *p, UINT p_length, UCHAR *q, UINT q_length,
const UCHAR *input, UINT input_length, UCHAR *output,
USHORT *scratch_buf_ptr, UINT scratch_buf_length)
{
HN_UBASE *scratch;
UINT mod_length;
NX_CRYPTO_HUGE_NUMBER modulus_hn, exponent_hn, input_hn, output_hn, p_hn, q_hn;
NX_CRYPTO_PARAMETER_NOT_USED(scratch_buf_length);
/* The RSA operation is reversible so both encryption and decryption can be done with the same operation. */
/* Local pointer for pointer arithmetic. */
scratch = (HN_UBASE *)scratch_buf_ptr;
/* Set up each of the buffers - point into the scratch buffer at increments of the DH buffer size. */
NX_CRYPTO_HUGE_NUMBER_INITIALIZE(&modulus_hn, scratch, modulus_length);
/* Input buffer(and scratch). */
NX_CRYPTO_HUGE_NUMBER_INITIALIZE(&input_hn, scratch, modulus_length);
/* Exponent buffer (and scratch). */
NX_CRYPTO_HUGE_NUMBER_INITIALIZE(&exponent_hn, scratch, modulus_length);
/* Output buffer (and scratch). */
NX_CRYPTO_HUGE_NUMBER_INITIALIZE(&output_hn, scratch, modulus_length << 1);
/* Copy the exponent from the caller's buffer. */
_nx_crypto_huge_number_setup(&exponent_hn, exponent, exponent_length);
/* Copy the input from the caller's buffer. */
_nx_crypto_huge_number_setup(&input_hn, input, input_length);
/* Copy the modulus from the caller's buffer. */
_nx_crypto_huge_number_setup(&modulus_hn, modulus, modulus_length);
if (p && q)
{
NX_CRYPTO_HUGE_NUMBER_INITIALIZE(&p_hn, scratch, modulus_length >> 1);
NX_CRYPTO_HUGE_NUMBER_INITIALIZE(&q_hn, scratch, modulus_length >> 1);
/* Copy the prime p and q from the caller's buffer. */
_nx_crypto_huge_number_setup(&p_hn, p, p_length);
_nx_crypto_huge_number_setup(&q_hn, q, q_length);
/* Finally, generate shared secret from the remote public key, our generated private key, and the modulus, modulus.
The actual calculation is "shared_secret = (public_key**private_key) % modulus"
where the "**" denotes exponentiation. */
_nx_crypto_huge_number_crt_power_modulus(&input_hn, &exponent_hn, &p_hn, &q_hn,
&modulus_hn, &output_hn,
scratch);
}
else
{
/* Finally, generate shared secret from the remote public key, our generated private key, and the modulus, modulus.
The actual calculation is "shared_secret = (public_key**private_key) % modulus"
where the "**" denotes exponentiation. */
_nx_crypto_huge_number_mont_power_modulus(&input_hn, &exponent_hn, &modulus_hn,
&output_hn, scratch);
}
/* Copy the shared secret into the return buffer. */
_nx_crypto_huge_number_extract(&output_hn, output, modulus_length, &mod_length);
return(NX_CRYPTO_SUCCESS);
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _nx_crypto_method_rsa_init PORTABLE C */
/* 6.4.3 */
/* AUTHOR */
/* */
/* Timothy Stapko, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function initializes the modulus for RSA context. */
/* */
/* INPUT */
/* */
/* method Pointer to RSA crypto method */
/* key Pointer to modulus */
/* key_size_in_bits Length of modulus in bits */
/* handle Handle of method */
/* crypto_metadata Pointer to RSA context */
/* crypto_metadata_size Size of RSA context */
/* */
/* OUTPUT */
/* */
/* status Completion status */
/* */
/* CALLS */
/* */
/* None */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/**************************************************************************/
NX_CRYPTO_KEEP UINT _nx_crypto_method_rsa_init(struct NX_CRYPTO_METHOD_STRUCT *method,
UCHAR *key, NX_CRYPTO_KEY_SIZE key_size_in_bits,
VOID **handle,
VOID *crypto_metadata,
ULONG crypto_metadata_size)
{
NX_CRYPTO_RSA *ctx;
NX_CRYPTO_PARAMETER_NOT_USED(handle);
NX_CRYPTO_STATE_CHECK
if ((method == NX_CRYPTO_NULL) || (key == NX_CRYPTO_NULL) || (crypto_metadata == NX_CRYPTO_NULL))
{
return(NX_CRYPTO_PTR_ERROR);
}
/* Verify the metadata address is 4-byte aligned. */
if((((ULONG)crypto_metadata) & 0x3) != 0)
{
return(NX_CRYPTO_PTR_ERROR);
}
if(crypto_metadata_size < sizeof(NX_CRYPTO_RSA))
{
return(NX_CRYPTO_PTR_ERROR);
}
ctx = (NX_CRYPTO_RSA *)crypto_metadata;
ctx -> nx_crypto_rsa_modulus = key;
ctx -> nx_crypto_rsa_modulus_length = key_size_in_bits >> 3;
ctx -> nx_crypto_rsa_prime_p = NX_CRYPTO_NULL;
ctx -> nx_crypto_rsa_prime_p_length = 0;
ctx -> nx_crypto_rsa_prime_q = NX_CRYPTO_NULL;
ctx -> nx_crypto_rsa_prime_q_length = 0;
/* Call _nx_crypto_crypto_rsa_set_prime() to set p and q for private key.
* Chinese Remainder Theorem will be used when p and q are set. */
return(NX_CRYPTO_SUCCESS);
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _nx_crypto_method_rsa_cleanup PORTABLE C */
/* 6.4.3 */
/* AUTHOR */
/* */
/* Timothy Stapko, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function cleans up the crypto metadata. */
/* */
/* INPUT */
/* */
/* crypto_metadata Crypto metadata */
/* */
/* OUTPUT */
/* */
/* status Completion status */
/* */
/* CALLS */
/* */
/* NX_CRYPTO_MEMSET Set the memory */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/**************************************************************************/
NX_CRYPTO_KEEP UINT _nx_crypto_method_rsa_cleanup(VOID *crypto_metadata)
{
NX_CRYPTO_STATE_CHECK
#ifdef NX_SECURE_KEY_CLEAR
if (!crypto_metadata)
return (NX_CRYPTO_SUCCESS);
/* Clean up the crypto metadata. */
NX_CRYPTO_MEMSET(crypto_metadata, 0, sizeof(NX_CRYPTO_RSA));
#else
NX_CRYPTO_PARAMETER_NOT_USED(crypto_metadata);
#endif/* NX_SECURE_KEY_CLEAR */
return(NX_CRYPTO_SUCCESS);
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _nx_crypto_method_rsa_operation PORTABLE C */
/* 6.4.3 */
/* AUTHOR */
/* */
/* Timothy Stapko, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function is the RSA operation function for crypto method. */
/* */
/* INPUT */
/* */
/* op Operation */
/* handle Handle to method */
/* method Pointer to RSA crypto method */
/* key Exponent of RSA operation */
/* key_size_in_bits Size of exponent in bits */
/* input Input stream */
/* input_length_in_byte Length of input in byte */
/* iv_ptr Initial Vector (not used) */
/* output Output stream */
/* output_length_in_byte Length of output in byte */
/* crypto_metadata Pointer to RSA context */
/* crypto_metadata_size Size of RSA context */
/* packet_ptr Pointer to packet (not used) */
/* nx_crypto_hw_process_callback Pointer to callback function */
/* (not used) */
/* */
/* OUTPUT */
/* */
/* status Completion status */
/* */
/* CALLS */
/* */
/* _nx_crypto_rsa_operation Perform RSA operation */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/**************************************************************************/
NX_CRYPTO_KEEP UINT _nx_crypto_method_rsa_operation(UINT op, /* Encrypt, Decrypt, Authenticate */
VOID *handle, /* Crypto handler */
struct NX_CRYPTO_METHOD_STRUCT *method,
UCHAR *key,
NX_CRYPTO_KEY_SIZE key_size_in_bits,
UCHAR *input,
ULONG input_length_in_byte,
UCHAR *iv_ptr,
UCHAR *output,
ULONG output_length_in_byte,
VOID *crypto_metadata,
ULONG crypto_metadata_size,
VOID *packet_ptr,
VOID (*nx_crypto_hw_process_callback)(VOID *packet_ptr, UINT status))
{
NX_CRYPTO_RSA *ctx;
UINT return_value = NX_CRYPTO_SUCCESS;
NX_CRYPTO_PARAMETER_NOT_USED(handle);
NX_CRYPTO_PARAMETER_NOT_USED(iv_ptr);
NX_CRYPTO_PARAMETER_NOT_USED(packet_ptr);
NX_CRYPTO_PARAMETER_NOT_USED(nx_crypto_hw_process_callback);
NX_CRYPTO_STATE_CHECK
/* Verify the metadata address is 4-byte aligned. */
if((method == NX_CRYPTO_NULL) || (crypto_metadata == NX_CRYPTO_NULL) || ((((ULONG)crypto_metadata) & 0x3) != 0))
{
return(NX_CRYPTO_PTR_ERROR);
}
if(crypto_metadata_size < sizeof(NX_CRYPTO_RSA))
{
return(NX_CRYPTO_PTR_ERROR);
}
ctx = (NX_CRYPTO_RSA *)crypto_metadata;
if (op == NX_CRYPTO_SET_PRIME_P)
{
ctx -> nx_crypto_rsa_prime_p = input;
ctx -> nx_crypto_rsa_prime_p_length = input_length_in_byte;
}
else if (op == NX_CRYPTO_SET_PRIME_Q)
{
ctx -> nx_crypto_rsa_prime_q = input;
ctx -> nx_crypto_rsa_prime_q_length = input_length_in_byte;
}
else
{
if (key == NX_CRYPTO_NULL)
{
return(NX_CRYPTO_PTR_ERROR);
}
if(output_length_in_byte < (key_size_in_bits >> 3))
return(NX_CRYPTO_INVALID_BUFFER_SIZE);
if (input_length_in_byte > (ctx -> nx_crypto_rsa_modulus_length))
{
return(NX_CRYPTO_PTR_ERROR);
}
return_value = _nx_crypto_rsa_operation(key,
key_size_in_bits >> 3,
ctx -> nx_crypto_rsa_modulus,
ctx -> nx_crypto_rsa_modulus_length,
ctx -> nx_crypto_rsa_prime_p,
ctx -> nx_crypto_rsa_prime_p_length,
ctx -> nx_crypto_rsa_prime_q,
ctx -> nx_crypto_rsa_prime_q_length,
input, input_length_in_byte,
output,
ctx -> nx_crypto_rsa_scratch_buffer,
NX_CRYPTO_RSA_SCRATCH_BUFFER_SIZE);
}
return(return_value);
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _nx_crypto_rsa_pss_mgf1 PORTABLE C */
/* 6.4.3 */
/* DESCRIPTION */
/* */
/* Mask Generation Function 1 (MGF1) as defined in RFC 8017 §B.2.1. */
/* Generates a pseudo-random octet string of length mask_length from */
/* a seed, using the supplied hash function. */
/* */
/* INPUT */
/* */
/* hash_method Hash function (e.g. SHA-256/384/512) */
/* hash_metadata Scratch memory for hash operations */
/* hash_metadata_size Size of hash_metadata in bytes */
/* seed MGF seed (typically the PSS H value) */
/* seed_length Length of seed in bytes */
/* mask Output buffer for generated mask */
/* mask_length Desired mask length in bytes */
/* */
/* OUTPUT */
/* */
/* status NX_CRYPTO_SUCCESS or error code */
/* */
/**************************************************************************/
static UINT _nx_crypto_rsa_pss_mgf1(const NX_CRYPTO_METHOD *hash_method,
VOID *hash_metadata, ULONG hash_metadata_size,
const UCHAR *seed, UINT seed_length,
UCHAR *mask, UINT mask_length)
{
UINT counter;
UINT offset;
UINT copy_len;
UINT hash_len;
UINT status;
UCHAR counter_bytes[4];
UCHAR hash_buf[64]; /* large enough for SHA-512 */
VOID *handler = NX_CRYPTO_NULL;
hash_len = (UINT)(hash_method -> nx_crypto_ICV_size_in_bits >> 3);
/* Sanity check: hash_buf must be large enough to hold one hash output. */
if (hash_len == 0u || hash_len > sizeof(hash_buf))
{
return(NX_CRYPTO_INVALID_BUFFER_SIZE);
}
offset = 0;
for (counter = 0; offset < mask_length; counter++)
{
counter_bytes[0] = (UCHAR)((counter >> 24) & 0xFFu);
counter_bytes[1] = (UCHAR)((counter >> 16) & 0xFFu);
counter_bytes[2] = (UCHAR)((counter >> 8) & 0xFFu);
counter_bytes[3] = (UCHAR)( counter & 0xFFu);
if (hash_method -> nx_crypto_init)
{
status = hash_method -> nx_crypto_init((NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
&handler,
hash_metadata, hash_metadata_size);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
}
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_INITIALIZE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
NX_CRYPTO_NULL, 0, NX_CRYPTO_NULL,
NX_CRYPTO_NULL, 0,
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_UPDATE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
(UCHAR *)seed, (ULONG)seed_length,
NX_CRYPTO_NULL,
NX_CRYPTO_NULL, 0,
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_UPDATE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
counter_bytes, 4,
NX_CRYPTO_NULL,
NX_CRYPTO_NULL, 0,
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_CALCULATE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
NX_CRYPTO_NULL, 0,
NX_CRYPTO_NULL,
hash_buf, (ULONG)sizeof(hash_buf),
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
copy_len = mask_length - offset;
if (copy_len > hash_len)
{
copy_len = hash_len;
}
NX_CRYPTO_MEMCPY(&mask[offset], hash_buf, copy_len); /* Use case of memcpy is verified. */
offset += copy_len;
}
return(NX_CRYPTO_SUCCESS);
}
/**************************************************************************/
/* */
/* FUNCTION RELEASE */
/* */
/* _nx_crypto_rsa_pss_verify PORTABLE C */
/* 6.4.3 */
/* DESCRIPTION */
/* */
/* Verifies an RSA-PSS signature encoding (RFC 8017 §9.1.2). */
/* Used by TLS 1.3 CertificateVerify processing. */
/* Assumes salt length == hash length (required by RFC 8446 §4.2.3). */
/* */
/* INPUT */
/* */
/* message_hash Pre-computed mHash over the signed content */
/* hash_length hLen = byte length of mHash */
/* em Encoded message from RSA public-key operation */
/* em_bits emBits = modulus_bits - 1 */
/* hash_method Same hash used to build the PSS encoding */
/* hash_metadata Scratch memory for hash operations */
/* hash_metadata_size Size of hash_metadata in bytes */
/* scratch Work buffer; must be >= ceil(emBits/8) bytes */
/* scratch_length Size of scratch in bytes */
/* */
/* OUTPUT */
/* */
/* NX_CRYPTO_SUCCESS Signature is valid */
/* NX_CRYPTO_NOT_SUCCESSFUL Signature is invalid */
/* NX_CRYPTO_INVALID_BUFFER_SIZE Buffers too small */
/* */
/**************************************************************************/
UINT _nx_crypto_rsa_pss_verify(const UCHAR *message_hash, UINT hash_length,
const UCHAR *em, UINT em_bits,
const NX_CRYPTO_METHOD *hash_method,
VOID *hash_metadata, ULONG hash_metadata_size,
UCHAR *scratch, UINT scratch_length)
{
UINT em_len;
UINT db_len;
UINT s_len;
UINT i;
UINT status;
UCHAR zero_bits;
UCHAR *db;
UCHAR *h_prime;
const UCHAR *h;
const UCHAR *masked_db;
VOID *handler = NX_CRYPTO_NULL;
static const UCHAR _pss_zero8[8] = {0, 0, 0, 0, 0, 0, 0, 0};
/* emLen = ceil(emBits / 8). */
em_len = (em_bits + 7u) >> 3;
/* TLS 1.3 mandates salt length == hash length (RFC 8446 §4.2.3). */
s_len = hash_length;
if (em_len < (hash_length + s_len + 2u))
{
return(NX_CRYPTO_NOT_SUCCESSFUL);
}
db_len = em_len - hash_length - 1u;
/* scratch layout: db[db_len] | h_prime[hash_length]. */
if (scratch_length < (db_len + hash_length))
{
return(NX_CRYPTO_INVALID_BUFFER_SIZE);
}
db = scratch;
h_prime = scratch + db_len;
/* Step 4 – last byte must be 0xBC. */
if (em[em_len - 1u] != 0xBCu)
{
return(NX_CRYPTO_NOT_SUCCESSFUL);
}
/* maskedDB = em[0..db_len-1], H = em[db_len..em_len-2]. */
masked_db = em;
h = em + db_len;
/* Step 6 – top (8*emLen - emBits) bits of em[0] must be zero. */
zero_bits = (UCHAR)(8u * em_len - em_bits);
if (zero_bits && (em[0] & (UCHAR)(0xFFu << (8u - zero_bits))))
{
return(NX_CRYPTO_NOT_SUCCESSFUL);
}
/* Step 7 – dbMask = MGF1(H, db_len). */
status = _nx_crypto_rsa_pss_mgf1(hash_method, hash_metadata, hash_metadata_size,
h, hash_length, db, db_len);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
/* Step 8 – DB = maskedDB XOR dbMask. */
for (i = 0u; i < db_len; i++)
{
db[i] ^= masked_db[i];
}
/* Step 9 – zero the top bits of DB[0]. */
if (zero_bits)
{
db[0] &= (UCHAR)(0xFFu >> zero_bits);
}
/* Steps 10-11 – PS (all zeros) then 0x01 separator. */
for (i = 0u; i < db_len - s_len - 1u; i++)
{
if (db[i] != 0x00u)
{
return(NX_CRYPTO_NOT_SUCCESSFUL);
}
}
if (db[db_len - s_len - 1u] != 0x01u)
{
return(NX_CRYPTO_NOT_SUCCESSFUL);
}
/* Steps 13-14 – H' = Hash(0x00^8 || mHash || salt). */
if (hash_method -> nx_crypto_init)
{
status = hash_method -> nx_crypto_init((NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
&handler,
hash_metadata, hash_metadata_size);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
}
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_INITIALIZE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
NX_CRYPTO_NULL, 0, NX_CRYPTO_NULL,
NX_CRYPTO_NULL, 0,
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
/* Hash 8 zero bytes. */
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_UPDATE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
(UCHAR *)_pss_zero8, 8,
NX_CRYPTO_NULL,
NX_CRYPTO_NULL, 0,
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
/* Hash mHash. */
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_UPDATE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
(UCHAR *)message_hash, (ULONG)hash_length,
NX_CRYPTO_NULL,
NX_CRYPTO_NULL, 0,
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
/* Hash salt = DB[db_len - s_len .. db_len - 1]. */
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_UPDATE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
&db[db_len - s_len], (ULONG)s_len,
NX_CRYPTO_NULL,
NX_CRYPTO_NULL, 0,
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
status = hash_method -> nx_crypto_operation(NX_CRYPTO_HASH_CALCULATE,
handler, (NX_CRYPTO_METHOD *)hash_method,
NX_CRYPTO_NULL, 0,
NX_CRYPTO_NULL, 0, NX_CRYPTO_NULL,
h_prime, (ULONG)hash_length,
hash_metadata, hash_metadata_size,
NX_CRYPTO_NULL, NX_CRYPTO_NULL);
if (status != NX_CRYPTO_SUCCESS)
{
return(status);
}
/* Step 15 – compare H == H'. */
if (NX_CRYPTO_MEMCMP(h, h_prime, hash_length) != 0)
{
return(NX_CRYPTO_NOT_SUCCESSFUL);
}
return(NX_CRYPTO_SUCCESS);
}
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