/* SPDX-License-Identifier: BSD-2-Clause */ /******************************************************************************* * Copyright 2017-2018, Fraunhofer SIT sponsored by Infineon Technologies AG * All rights reserved. ******************************************************************************/ #ifdef HAVE_CONFIG_H #include #endif #include #include "tss2_esys.h" #include "esys_crypto.h" #include "esys_iutil.h" #include "esys_mu.h" #define LOGMODULE esys_crypto #include "util/log.h" #include "util/aux_util.h" /** Provide the digest size for a given hash algorithm. * * This function provides the size of the digest for a given hash algorithm. * * @param[in] hashAlg The hash algorithm to get the size for. * @param[out] size The side of a digest of the hash algorithm. * @retval TSS2_RC_SUCCESS on success. * @retval TSS2_ESYS_RC_BAD_VALUE if hashAlg is unknown or unsupported. */ TSS2_RC iesys_crypto_hash_get_digest_size(TPM2_ALG_ID hashAlg, size_t * size) { LOG_TRACE("call: hashAlg=%"PRIu16" size=%p", hashAlg, size); if (size == NULL) { LOG_ERROR("Null-Pointer passed"); return TSS2_ESYS_RC_BAD_REFERENCE; } switch (hashAlg) { case TPM2_ALG_SHA1: *size = TPM2_SHA1_DIGEST_SIZE; break; case TPM2_ALG_SHA256: *size = TPM2_SHA256_DIGEST_SIZE; break; case TPM2_ALG_SHA384: *size = TPM2_SHA384_DIGEST_SIZE; break; case TPM2_ALG_SHA512: *size = TPM2_SHA512_DIGEST_SIZE; break; case TPM2_ALG_SM3_256: *size = TPM2_SM3_256_DIGEST_SIZE; break; default: LOG_ERROR("Unsupported hash algorithm (%"PRIu16")", hashAlg); return TSS2_ESYS_RC_BAD_VALUE; } LOG_TRACE("return: *size=%zu", *size); return TSS2_RC_SUCCESS; } /** Compute the command or response parameter hash. * * These hashes are needed for the computation of the HMAC used for the * authorization of commands, or for the HMAC used for checking the responses. * The name parameters are only used for the command parameter hash (cp) and * must be NULL for the computation of the response parameter rp hash (rp). * @param[in] alg The hash algorithm. * @param[in] rcBuffer The response code in marshaled form. * @param[in] ccBuffer The command code in marshaled form. * @param[in] name1, name2, name3 The names associated with the corresponding * handle. Must be NULL if no handle is passed. * @param[in] pBuffer The byte buffer or the command or the response. * @param[in] pBuffer_size The size of the command or response. * @param[out] pHash The result digest. * @param[out] pHash_size The size of the result digest. * @retval TSS2_RC_SUCCESS on success. * @retval TSS2_ESYS_RC_BAD_REFERENCE for invalid parameters. */ TSS2_RC iesys_crypto_pHash(TPM2_ALG_ID alg, const uint8_t rcBuffer[4], const uint8_t ccBuffer[4], const TPM2B_NAME * name1, const TPM2B_NAME * name2, const TPM2B_NAME * name3, const uint8_t * pBuffer, size_t pBuffer_size, uint8_t * pHash, size_t * pHash_size) { LOG_TRACE("called"); if (ccBuffer == NULL || pBuffer == NULL || pHash == NULL || pHash_size == NULL) { LOG_ERROR("Null-Pointer passed"); return TSS2_ESYS_RC_BAD_REFERENCE; } IESYS_CRYPTO_CONTEXT_BLOB *cryptoContext; TSS2_RC r = iesys_crypto_hash_start(&cryptoContext, alg); return_if_error(r, "Error"); if (rcBuffer != NULL) { r = iesys_crypto_hash_update(cryptoContext, &rcBuffer[0], 4); goto_if_error(r, "Error", error); } r = iesys_crypto_hash_update(cryptoContext, &ccBuffer[0], 4); goto_if_error(r, "Error", error); if (name1 != NULL) { r = iesys_crypto_hash_update2b(cryptoContext, (TPM2B *) name1); goto_if_error(r, "Error", error); } if (name2 != NULL) { r = iesys_crypto_hash_update2b(cryptoContext, (TPM2B *) name2); goto_if_error(r, "Error", error); } if (name3 != NULL) { r = iesys_crypto_hash_update2b(cryptoContext, (TPM2B *) name3); goto_if_error(r, "Error", error); } r = iesys_crypto_hash_update(cryptoContext, pBuffer, pBuffer_size); goto_if_error(r, "Error", error); r = iesys_crypto_hash_finish(&cryptoContext, pHash, pHash_size); goto_if_error(r, "Error", error); return r; error: iesys_crypto_hash_abort(&cryptoContext); return r; } /** Compute the HMAC for authorization. * * Based on the session nonces, caller nonce, TPM nonce, if used encryption and * decryption nonce, the command parameter hash, and the session attributes the * HMAC used for authorization is computed. * @param[in] alg The hash algorithm used for HMAC computation. * @param[in] hmacKey The HMAC key byte buffer. * @param[in] hmacKeySize The size of the HMAC key byte buffer. * @param[in] pHash The command parameter hash byte buffer. * @param[in] pHash_size The size of the command parameter hash byte buffer. * @param[in] nonceNewer The TPM nonce. * @param[in] nonceOlder The caller nonce. * @param[in] nonceDecrypt The decrypt nonce (NULL if not used). * @param[in] nonceEncrypt The encrypt nonce (NULL if not used). * @param[in] sessionAttributes The attributes used for the current * authentication. * @param[out] hmac The computed HMAC. * @retval TSS2_RC_SUCCESS on success * @retval TSS2_ESYS_RC_BAD_REFERENCE If a pointer is invalid. */ TSS2_RC iesys_crypto_authHmac(TPM2_ALG_ID alg, uint8_t * hmacKey, size_t hmacKeySize, const uint8_t * pHash, size_t pHash_size, const TPM2B_NONCE * nonceNewer, const TPM2B_NONCE * nonceOlder, const TPM2B_NONCE * nonceDecrypt, const TPM2B_NONCE * nonceEncrypt, TPMA_SESSION sessionAttributes, TPM2B_AUTH * hmac) { LOG_TRACE("called"); if (hmacKey == NULL || pHash == NULL || nonceNewer == NULL || nonceOlder == NULL || hmac == NULL) { LOG_ERROR("Null-Pointer passed"); return TSS2_ESYS_RC_BAD_REFERENCE; } uint8_t sessionAttribs[sizeof(sessionAttributes)]; size_t sessionAttribs_size = 0; IESYS_CRYPTO_CONTEXT_BLOB *cryptoContext; TSS2_RC r = iesys_crypto_hmac_start(&cryptoContext, alg, hmacKey, hmacKeySize); return_if_error(r, "Error"); r = iesys_crypto_hmac_update(cryptoContext, pHash, pHash_size); goto_if_error(r, "Error", error); r = iesys_crypto_hmac_update2b(cryptoContext, (TPM2B *) nonceNewer); goto_if_error(r, "Error", error); r = iesys_crypto_hmac_update2b(cryptoContext, (TPM2B *) nonceOlder); goto_if_error(r, "Error", error); if (nonceDecrypt != NULL) { r = iesys_crypto_hmac_update2b(cryptoContext, (TPM2B *) nonceDecrypt); goto_if_error(r, "Error", error); } if (nonceEncrypt != NULL) { r = iesys_crypto_hmac_update2b(cryptoContext, (TPM2B *) nonceEncrypt); goto_if_error(r, "Error", error); } r = Tss2_MU_TPMA_SESSION_Marshal(sessionAttributes, &sessionAttribs[0], sizeof(sessionAttribs), &sessionAttribs_size); goto_if_error(r, "Error", error); r = iesys_crypto_hmac_update(cryptoContext, &sessionAttribs[0], sessionAttribs_size); goto_if_error(r, "Error", error); r = iesys_crypto_hmac_finish2b(&cryptoContext, (TPM2B *) hmac); goto_if_error(r, "Error", error); return r; error: iesys_crypto_hmac_abort(&cryptoContext); return r; } /** * HMAC computation for inner loop of KDFa key derivation. * * Except of ECDH this function is used for key derivation. * @param[in] alg The algorithm used for the HMAC. * @param[in] hmacKey The hmacKey used in KDFa. * @param[in] hmacKeySize The size of the HMAC key. * @param[in] counter The curren iteration step. * @param[in] label Indicates the use of the produced key. * @param[in] contextU, contextV are used for construction of a binary string * containing information related to the derived key. * @param[in] bitlength The size of the generated key in bits. * @param[out] hmac Byte buffer for the generated HMAC key (caller-allocated). * @param[out] hmacSize Size of the generated HMAC key. * @retval TSS2_RC_SUCCESS on success. * @retval TSS2_ESYS_RC_BAD_REFERENCE for invalid parameters. */ TSS2_RC iesys_crypto_KDFaHmac(TPM2_ALG_ID alg, uint8_t * hmacKey, size_t hmacKeySize, uint32_t counter, const char *label, TPM2B_NONCE * contextU, TPM2B_NONCE * contextV, uint32_t bitlength, uint8_t * hmac, size_t * hmacSize) { LOG_TRACE("called"); if (hmacKey == NULL || contextU == NULL || contextV == NULL) { LOG_ERROR("Null-Pointer passed"); return TSS2_ESYS_RC_BAD_REFERENCE; } uint8_t buffer32[sizeof(uint32_t)]; size_t buffer32_size = 0; IESYS_CRYPTO_CONTEXT_BLOB *cryptoContext; TSS2_RC r = iesys_crypto_hmac_start(&cryptoContext, alg, hmacKey, hmacKeySize); return_if_error(r, "Error"); r = Tss2_MU_UINT32_Marshal(counter, &buffer32[0], sizeof(UINT32), &buffer32_size); goto_if_error(r, "Marsahling", error); r = iesys_crypto_hmac_update(cryptoContext, &buffer32[0], buffer32_size); goto_if_error(r, "HMAC-Update", error); if (label != NULL) { size_t lsize = strlen(label) + 1; r = iesys_crypto_hmac_update(cryptoContext, (uint8_t *) label, lsize); goto_if_error(r, "Error", error); } r = iesys_crypto_hmac_update2b(cryptoContext, (TPM2B *) contextU); goto_if_error(r, "Error", error); r = iesys_crypto_hmac_update2b(cryptoContext, (TPM2B *) contextV); goto_if_error(r, "Error", error); buffer32_size = 0; r = Tss2_MU_UINT32_Marshal(bitlength, &buffer32[0], sizeof(UINT32), &buffer32_size); goto_if_error(r, "Marsahling", error); r = iesys_crypto_hmac_update(cryptoContext, &buffer32[0], buffer32_size); goto_if_error(r, "Error", error); r = iesys_crypto_hmac_finish(&cryptoContext, hmac, hmacSize); goto_if_error(r, "Error", error); return r; error: iesys_crypto_hmac_abort(&cryptoContext); return r; } /** * KDFa Key derivation. * * Except of ECDH this function is used for key derivation. * @param[in] hashAlg The hash algorithm to use. * @param[in] hmacKey The hmacKey used in KDFa. * @param[in] hmacKeySize The size of the HMAC key. * @param[in] label Indicates the use of the produced key. * @param[in] contextU, contextV are used for construction of a binary string * containing information related to the derived key. * @param[in] bitLength The size of generated key in bits. * @param[in,out] counterInOut Counter for the KDFa iterations. If set, the * value will be used for the firt iteration step. The final * counter value will be written to counterInOut. * @param[out] outKey Byte buffer for the derived key (caller-allocated). * @param[in] use_digest_size Indicate whether the digest size of hashAlg is * used as size of the generated key or the bitLength parameter is * used. * @retval TSS2_RC_SUCCESS on success. * @retval TSS2_ESYS_RC_BAD_VALUE if hashAlg is unknown or unsupported. */ TSS2_RC iesys_crypto_KDFa(TPM2_ALG_ID hashAlg, uint8_t * hmacKey, size_t hmacKeySize, const char *label, TPM2B_NONCE * contextU, TPM2B_NONCE * contextV, uint32_t bitLength, uint32_t * counterInOut, BYTE * outKey, BOOL use_digest_size) { LOG_DEBUG("IESYS KDFa hmac key hashAlg: %i label: %s bitLength: %i", hashAlg, label, bitLength); if (counterInOut != NULL) LOG_TRACE("IESYS KDFa hmac key counterInOut: %i", *counterInOut); LOGBLOB_DEBUG(hmacKey, hmacKeySize, "IESYS KDFa hmac key"); LOGBLOB_DEBUG(&contextU->buffer[0], contextU->size, "IESYS KDFa contextU key"); LOGBLOB_DEBUG(&contextV->buffer[0], contextV->size, "IESYS KDFa contextV key"); BYTE *subKey = outKey; UINT32 counter = 0; INT32 bytes = 0; size_t hlen = 0; TSS2_RC r = iesys_crypto_hash_get_digest_size(hashAlg, &hlen); return_if_error(r, "Error"); if (counterInOut != NULL) counter = *counterInOut; bytes = use_digest_size ? hlen : (bitLength + 7) / 8; LOG_DEBUG("IESYS KDFa hmac key bytes: %i", bytes); /* Fill outKey with results from KDFaHmac */ for (; bytes > 0; subKey = &subKey[hlen], bytes = bytes - hlen) { LOG_TRACE("IESYS KDFa hmac key bytes: %i", bytes); //if(bytes < (INT32)hlen) // hlen = bytes; counter++; r = iesys_crypto_KDFaHmac(hashAlg, hmacKey, hmacKeySize, counter, label, contextU, contextV, bitLength, &subKey[0], &hlen); return_if_error(r, "Error"); } if ((bitLength % 8) != 0) outKey[0] &= ((1 << (bitLength % 8)) - 1); if (counterInOut != NULL) *counterInOut = counter; LOGBLOB_DEBUG(outKey, (bitLength + 7) / 8, "IESYS KDFa key"); return TPM2_RC_SUCCESS; } /** Compute KDFe as described in TPM spec part 1 C 6.1 * * @param hashAlg [in] The nameAlg of the recipient key. * @param Z [in] the x coordinate (xP) of the product (P) of a public point and a * private key. * @param label [in] KDF label. * @param partyUInfo [in] The x-coordinate of the secret exchange value (Qe,U). * @param partyVInfo [in] The x-coordinate of a public key (Qs,V). * @param bit_size [in] Bit size of generated key. * @param key [out] Key buffer. * @retval TSS2_RC_SUCCESS on success * @retval TSS2_ESYS_RC_BAD_REFERENCE for invalid parameters * @retval TSS2_ESYS_RC_MEMORY Memory cannot be allocated. */ TSS2_RC iesys_crypto_KDFe(TPM2_ALG_ID hashAlg, TPM2B_ECC_PARAMETER *Z, const char *label, TPM2B_ECC_PARAMETER *partyUInfo, TPM2B_ECC_PARAMETER *partyVInfo, UINT32 bit_size, BYTE *key) { TSS2_RC r = TSS2_RC_SUCCESS; size_t hash_len; INT16 byte_size = (INT16)((bit_size +7) / 8); BYTE *stream = key; IESYS_CRYPTO_CONTEXT_BLOB *cryptoContext; BYTE counter_buffer[4]; UINT32 counter = 0; size_t offset; LOG_DEBUG("IESYS KDFe hashAlg: %i label: %s bitLength: %i", hashAlg, label, bit_size); if (partyUInfo != NULL) LOGBLOB_DEBUG(&partyUInfo->buffer[0], partyUInfo->size, "partyUInfo"); if (partyVInfo != NULL) LOGBLOB_DEBUG(&partyVInfo->buffer[0], partyVInfo->size, "partyVInfo"); r = iesys_crypto_hash_get_digest_size(hashAlg, &hash_len); return_if_error(r, "Hash algorithm not supported."); if(hashAlg == TPM2_ALG_NULL || byte_size == 0) { LOG_DEBUG("Bad parameters for KDFe"); return TSS2_ESYS_RC_BAD_VALUE; } /* Fill seed key with hash of counter, Z, label, partyUInfo, and partyVInfo */ for (; byte_size > 0; stream = &stream[hash_len], byte_size = byte_size - hash_len) { counter ++; r = iesys_crypto_hash_start(&cryptoContext, hashAlg); return_if_error(r, "Error hash start"); offset = 0; r = Tss2_MU_UINT32_Marshal(counter, &counter_buffer[0], 4, &offset); goto_if_error(r, "Error marshaling counter", error); r = iesys_crypto_hash_update(cryptoContext, &counter_buffer[0], 4); goto_if_error(r, "Error hash update", error); if (Z != NULL) { r = iesys_crypto_hash_update2b(cryptoContext, (TPM2B *) Z); goto_if_error(r, "Error hash update2b", error); } if (label != NULL) { size_t lsize = strlen(label) + 1; r = iesys_crypto_hash_update(cryptoContext, (uint8_t *) label, lsize); goto_if_error(r, "Error hash update", error); } if (partyUInfo != NULL) { r = iesys_crypto_hash_update2b(cryptoContext, (TPM2B *) partyUInfo); goto_if_error(r, "Error hash update2b", error); } if (partyVInfo != NULL) { r = iesys_crypto_hash_update2b(cryptoContext, (TPM2B *) partyVInfo); goto_if_error(r, "Error hash update2b", error); } r = iesys_crypto_hash_finish(&cryptoContext, (uint8_t *) stream, &hash_len); goto_if_error(r, "Error", error); } LOGBLOB_DEBUG(key, bit_size/8, "Result KDFe"); if((bit_size % 8) != 0) key[0] &= ((1 << (bit_size % 8)) - 1); return r; error: iesys_crypto_hmac_abort(&cryptoContext); return r; } /** Encryption/Decryption using XOR obfuscation. * * The application of this function to data encrypted with this function will * produce the origin data. The key for XOR obfuscation will be derived with * KDFa form the passed key the session nonces, and the hash algorithm. * @param[in] hash_alg The algorithm used for key derivation. * @param[in] key key used for obfuscation * @param[in] key_size Key size in bits. * @param[in] contextU, contextV are used for construction of a binary string * containing information related to the derived key. * @param[in,out] data Data to be encrypted/decrypted the result will be * will be stored in this buffer. * @param[in] data_size size of data to be encrypted/decrypted. * @retval TSS2_RC_SUCCESS on success, or TSS2_ESYS_RC_BAD_VALUE and * @retval TSS2_ESYS_RC_BAD_REFERENCE for invalid parameters. */ TSS2_RC iesys_xor_parameter_obfuscation(TPM2_ALG_ID hash_alg, uint8_t *key, size_t key_size, TPM2B_NONCE * contextU, TPM2B_NONCE * contextV, BYTE *data, size_t data_size) { TSS2_RC r; uint32_t counter = 0; BYTE kdfa_result[TPM2_MAX_DIGEST_BUFFER]; size_t digest_size; size_t data_size_bits = data_size * 8; size_t rest_size = data_size; BYTE *kdfa_byte_ptr; if (key == NULL || data == NULL) { LOG_ERROR("Bad reference"); return TSS2_ESYS_RC_BAD_REFERENCE; } r = iesys_crypto_hash_get_digest_size(hash_alg, &digest_size); return_if_error(r, "Hash alg not supported"); while(rest_size > 0) { r = iesys_crypto_KDFa(hash_alg, key, key_size, "XOR", contextU, contextV, data_size_bits, &counter, kdfa_result, TRUE); return_if_error(r, "iesys_crypto_KDFa failed"); /* XOR next data sub block with KDFa result */ kdfa_byte_ptr = kdfa_result; LOGBLOB_TRACE(data, data_size, "Parameter data before XOR"); for(size_t i = digest_size < rest_size ? digest_size : rest_size; i > 0; i--) *data++ ^= *kdfa_byte_ptr++; LOGBLOB_TRACE(data, data_size, "Parameter data after XOR"); rest_size = rest_size < digest_size ? 0 : rest_size - digest_size; } return TSS2_RC_SUCCESS; } /** Initialize crypto backend. * * Initialize internal tables of crypto backend. * * @retval TSS2_RC_SUCCESS ong success. * @retval TSS2_ESYS_RC_GENERAL_FAILURE if backend can't be initialized. */ TSS2_RC iesys_initialize_crypto() { return iesys_crypto_init(); }