// Copyright (c) 2016, Monero Research Labs // // Author: Shen Noether // // All rights reserved. // // Redistribution and use in source and binary forms, with or without modification, are // permitted provided that the following conditions are met: // // 1. Redistributions of source code must retain the above copyright notice, this list of // conditions and the following disclaimer. // // 2. Redistributions in binary form must reproduce the above copyright notice, this list // of conditions and the following disclaimer in the documentation and/or other // materials provided with the distribution. // // 3. Neither the name of the copyright holder nor the names of its contributors may be // used to endorse or promote products derived from this software without specific // prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL // THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. #pragma once //#define DBG #ifndef RCTSIGS_H #define RCTSIGS_H #include #include #include #include #include "crypto/generic-ops.h" extern "C" { #include "crypto/random.h" #include "crypto/keccak.h" } #include "crypto/crypto.h" #include "rctTypes.h" #include "rctOps.h" //Define this flag when debugging to get additional info on the console #ifdef DBG #define DP(x) dp(x) #else #define DP(x) #endif using namespace std; using namespace crypto; namespace rct { //Schnorr Non-linkable //Gen Gives a signature (L1, s1, s2) proving that the sender knows "x" such that xG = one of P1 or P2 //Ver Verifies that signer knows an "x" such that xG = one of P1 or P2 //These are called in the below ASNL sig generation void GenSchnorrNonLinkable(key & L1, key & s1, key & s2, const key & x, const key & P1, const key & P2, unsigned int index); bool VerSchnorrNonLinkable(const key & P1, const key & P2, const key & L1, const key & s1, const key & s2); //Aggregate Schnorr Non-linkable Ring Signature (ASNL) // c.f. http://eprint.iacr.org/2015/1098 section 5. // These are used in range proofs (alternatively Borromean could be used) // Gen gives a signature which proves the signer knows, for each i, // an x[i] such that x[i]G = one of P1[i] or P2[i] // Ver Verifies the signer knows a key for one of P1[i], P2[i] at each i asnlSig GenASNL(key64 x, key64 P1, key64 P2, bits indices); bool VerASNL(const key64 P1, const key64 P2, const asnlSig &as); //Multilayered Spontaneous Anonymous Group Signatures (MLSAG signatures) //These are aka MG signatutes in earlier drafts of the ring ct paper // c.f. http://eprint.iacr.org/2015/1098 section 2. // keyImageV just does I[i] = xx[i] * HashToPoint(xx[i] * G) for each i // Gen creates a signature which proves that for some column in the keymatrix "pk" // the signer knows a secret key for each row in that column // Ver verifies that the MG sig was created correctly keyV keyImageV(const keyV &xx); mgSig MLSAG_Gen(const key &message, const keyM & pk, const keyV & xx, const unsigned int index, size_t dsRows); bool MLSAG_Ver(const key &message, const keyM &pk, const mgSig &sig, size_t dsRows); //mgSig MLSAG_Gen_Old(const keyM & pk, const keyV & xx, const int index); //proveRange and verRange //proveRange gives C, and mask such that \sumCi = C // c.f. http://eprint.iacr.org/2015/1098 section 5.1 // and Ci is a commitment to either 0 or 2^i, i=0,...,63 // thus this proves that "amount" is in [0, 2^64] // mask is a such that C = aG + bH, and b = amount //verRange verifies that \sum Ci = C and that each Ci is a commitment to 0 or 2^i rangeSig proveRange(key & C, key & mask, const xmr_amount & amount); bool verRange(const key & C, const rangeSig & as); //Ring-ct MG sigs //Prove: // c.f. http://eprint.iacr.org/2015/1098 section 4. definition 10. // This does the MG sig on the "dest" part of the given key matrix, and // the last row is the sum of input commitments from that column - sum output commitments // this shows that sum inputs = sum outputs //Ver: // verifies the above sig is created corretly mgSig proveRctMG(const ctkeyM & pubs, const ctkeyV & inSk, const keyV &outMasks, const ctkeyV & outPk, unsigned int index, key txnFee, const key &message); mgSig proveRctMGSimple(const key & message, const ctkeyV & pubs, const ctkey & inSk, const key &a , const key &Cout, unsigned int index); bool verRctMG(const mgSig &mg, const ctkeyM & pubs, const ctkeyV & outPk, key txnFee, const key &message); bool verRctMGSimple(const key &message, const mgSig &mg, const ctkeyV & pubs, const key & C); //These functions get keys from blockchain //replace these when connecting blockchain //getKeyFromBlockchain grabs a key from the blockchain at "reference_index" to mix with //populateFromBlockchain creates a keymatrix with "mixin" columns and one of the columns is inPk // the return value are the key matrix, and the index where inPk was put (random). void getKeyFromBlockchain(ctkey & a, size_t reference_index); tuple populateFromBlockchain(ctkeyV inPk, int mixin); //RingCT protocol //genRct: // creates an rctSig with all data necessary to verify the rangeProofs and that the signer owns one of the // columns that are claimed as inputs, and that the sum of inputs = sum of outputs. // Also contains masked "amount" and "mask" so the receiver can see how much they received //verRct: // verifies that all signatures (rangeProogs, MG sig, sum inputs = outputs) are correct //decodeRct: (c.f. http://eprint.iacr.org/2015/1098 section 5.1.1) // uses the attached ecdh info to find the amounts represented by each output commitment // must know the destination private key to find the correct amount, else will return a random number rctSig genRct(const key &message, const ctkeyV & inSk, const keyV & destinations, const vector & amounts, const ctkeyM &mixRing, const keyV &amount_keys, unsigned int index, ctkeyV &outSk); rctSig genRct(const key &message, const ctkeyV & inSk, const ctkeyV & inPk, const keyV & destinations, const vector & amounts, const keyV &amount_keys, const int mixin); rctSig genRctSimple(const key & message, const ctkeyV & inSk, const ctkeyV & inPk, const keyV & destinations, const vector & inamounts, const vector & outamounts, const keyV &amount_keys, xmr_amount txnFee, unsigned int mixin); rctSig genRctSimple(const key & message, const ctkeyV & inSk, const keyV & destinations, const vector & inamounts, const vector & outamounts, xmr_amount txnFee, const ctkeyM & mixRing, const keyV &amount_keys, const std::vector & index, ctkeyV &outSk); bool verRct(const rctSig & rv); bool verRctSimple(const rctSig & rv); xmr_amount decodeRct(const rctSig & rv, const key & sk, unsigned int i, key & mask); xmr_amount decodeRct(const rctSig & rv, const key & sk, unsigned int i); xmr_amount decodeRctSimple(const rctSig & rv, const key & sk, unsigned int i, key & mask); xmr_amount decodeRctSimple(const rctSig & rv, const key & sk, unsigned int i); } #endif /* RCTSIGS_H */