prp.h

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#include "block.h"
#include "config.h"
#include "garble/aes.h"
#include <stdio.h>
#ifndef PRP_H__
#define PRP_H__

class PRP { public:
    AES_KEY *aes;
    PRP(const char * seed = fix_key) {
        aes = new AES_KEY;
        aes_set_key(seed);
    }
    ~PRP() {
        delete aes;
    }
    void aes_set_key(const char * key) {
        __m128i v = _mm_load_si128((__m128i*)&key[0]);
        aes_set_key(v);
    }
    void aes_set_key(const block& v) {
        AES_set_encrypt_key(v, aes);
    }


    void permute_block(block *data, int nblocks) {
        int i = 0;
        for(; i < nblocks-AES_BATCH_SIZE; i+=AES_BATCH_SIZE) {
            AES_ecb_encrypt_blks(data+i, AES_BATCH_SIZE, aes);
        }
        AES_ecb_encrypt_blks(data+i, (AES_BATCH_SIZE >  nblocks-i) ? nblocks-i:AES_BATCH_SIZE, aes);
    }
    
    void permute_data(uint8_t*data, int nbytes) {
        permute_block((block *)data, nbytes/16);
        if (nbytes % 16 != 0) {
            uint8_t extra[16];
            memset(extra, 0, 16);
            memcpy(extra, (nbytes/16*16)+(char *) data, nbytes%16);
            permute_block((block*)extra, 1);
            memcpy((nbytes/16*16)+(char *) data, &extra, nbytes%16);
        }
    }

    block H(block in, uint64_t id) {
        in = double_block(in);
        __m128i k_128 = _mm_loadl_epi64( (__m128i const *) (&id));
        in = xorBlocks(in, k_128);
        block t = in;
        permute_block(&t, 1);
        in =  xorBlocks(in, t);
        return in;  
    }
    template<int n>
    void H(block out[n], block in[n], uint64_t id) {
        block scratch[n];
        for(int i = 0; i < n; ++i) {
            out[i] = scratch[i] = xorBlocks(double_block(in[i]), _mm_loadl_epi64( (__m128i const *) (&id)));
            ++id;
        }
        permute_block(scratch, n);
        xorBlocks_arr(out, scratch, out, n);
    }

    void Hn(block*out, block* in, uint64_t id, int length, block * scratch = nullptr) {
        bool del = false;
        if(scratch == nullptr) {
            del = true;
            scratch = new block[length];
        }
        for(int i = 0; i < length; ++i){
            out[i] = scratch[i] = xorBlocks(double_block(in[i]), _mm_loadl_epi64( (__m128i const *) (&id)));
            ++id;
        }
        permute_block(scratch, length);
        xorBlocks_arr(out, scratch, out, length);
        if(del) {
            delete[] scratch;
            scratch = nullptr;
        }
    }
};
#endif// PRP_H__