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- #include "Openssl_crypto.h"
- #include "SymmetricEncryptionBox.h"
- #include "sgx_trts.h"
- // increments last 4 bytes (in big-endian order)
- /* uint32_t SymmetricEncryptionBox::recursive_incrementer(uint32_t counter, uint32_t min_counter)
- {
- if(min_counter>counter)
- return 0xfe;
- if(iv[counter] != 0xff)
- {
- iv[counter]+=1;
- return 0;
- }
- else
- {
- iv[counter]=0;
- if(counter!=min_counter)
- // counter-1 refers to the overall counter in the iv string (counter+1 for little endian)
- return recursive_incrementer(counter-1,min_counter);
- else
- return 0xff;
- }
- }
- uint32_t SymmetricEncryptionBox::aes_gcm_increment_iv() {
- return recursive_incrementer(11, 8);
- }
- */
- void SymmetricEncryptionBox::set_symmetric_key(uint8_t* given_key)
- {
- uint32_t counter;
- for(counter=0; counter<16; counter++)
- symmetric_key[counter] = given_key[counter];
- }
- void SymmetricEncryptionBox::get_symmetric_key(uint8_t* op_key)
- {
- uint32_t counter;
- for(counter=0; counter<16; counter++)
- op_key[counter] = symmetric_key[counter];
- }
- // TODO: IMPORTANT - CHECK IF WE NEED TO DO THE AES GCM INCREMENT IV FOR DECRYPTION TOO.
- uint32_t SymmetricEncryptionBox::encrypt_decrypt(int enc, uint8_t* plaintext, uint32_t plaintext_length, uint8_t* ciphertext, uint32_t* ciphertext_length)
- {
- uint32_t actual_plaintext_length=plaintext_length;
- uint8_t tag[16];uint32_t counter, return_status;
- uint8_t iv[12];
- if(enc == 0) // decryption
- {
- for(counter=0;counter<16;counter++)
- tag[counter]=plaintext[counter+plaintext_length-16];
- for(counter=0;counter<12;counter++)
- iv[counter]=plaintext[counter+plaintext_length-28];
- actual_plaintext_length-=28;
- }
- else // encryption
- {
- return_status=sgx_read_rand(iv, 12);
- if(return_status != 0)
- return return_status;
- }
- return_status = aes_gcm_128(enc, symmetric_key, iv, plaintext, actual_plaintext_length, ciphertext, ciphertext_length, tag);
- if(enc == 1 && return_status ==0)
- {
- for(counter=0;counter<12;counter++)
- ciphertext[counter + *ciphertext_length] = iv[counter];
- for(counter=0;counter<16;counter++)
- ciphertext[counter + 12 + *ciphertext_length] = tag[counter];
- *ciphertext_length=*ciphertext_length + 28;
- }
- return return_status;
- }
- /* void SymmetricEncryptionBox::get_iv(uint8_t* op_iv)
- {
- uint32_t counter;
- for(counter=0;counter<12;counter++)
- op_iv[counter]=iv[counter];
- }
- */
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