503
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107
msr/include/P503_api.h
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107
msr/include/P503_api.h
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/********************************************************************************************
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* SIDH: an efficient supersingular isogeny cryptography library
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*
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* Abstract: API header file for P503
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*********************************************************************************************/
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#ifndef __P503_API_H__
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#define __P503_API_H__
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/*********************** Key encapsulation mechanism API ***********************/
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#define CRYPTO_SECRETKEYBYTES 434 // MSG_BYTES + SECRETKEY_B_BYTES + CRYPTO_PUBLICKEYBYTES bytes
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#define CRYPTO_PUBLICKEYBYTES 378
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#define CRYPTO_BYTES 16
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#define CRYPTO_CIPHERTEXTBYTES 402 // CRYPTO_PUBLICKEYBYTES + MSG_BYTES bytes
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// Algorithm name
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#define CRYPTO_ALGNAME "SIKEp503"
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// SIKE's key generation
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// It produces a private key sk and computes the public key pk.
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// Outputs: secret key sk (CRYPTO_SECRETKEYBYTES = 434 bytes)
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// public key pk (CRYPTO_PUBLICKEYBYTES = 378 bytes)
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int crypto_kem_keypair_SIKEp503(unsigned char *pk, unsigned char *sk);
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// SIKE's encapsulation
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// Input: public key pk (CRYPTO_PUBLICKEYBYTES = 378 bytes)
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// Outputs: shared secret ss (CRYPTO_BYTES = 16 bytes)
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// ciphertext message ct (CRYPTO_CIPHERTEXTBYTES = 402 bytes)
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int crypto_kem_enc_SIKEp503(unsigned char *ct, unsigned char *ss, const unsigned char *pk);
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// SIKE's decapsulation
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// Input: secret key sk (CRYPTO_SECRETKEYBYTES = 434 bytes)
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// ciphertext message ct (CRYPTO_CIPHERTEXTBYTES = 402 bytes)
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// Outputs: shared secret ss (CRYPTO_BYTES = 16 bytes)
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int crypto_kem_dec_SIKEp503(unsigned char *ss, const unsigned char *ct, const unsigned char *sk);
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// Encoding of keys for KEM-based isogeny system "SIKEp503" (wire format):
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// ----------------------------------------------------------------------
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// Elements over GF(p503) are encoded in 63 octets in little endian format (i.e., the least significant octet is located in the lowest memory address).
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// Elements (a+b*i) over GF(p503^2), where a and b are defined over GF(p503), are encoded as {a, b}, with a in the lowest memory portion.
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//
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// Private keys sk consist of the concatenation of a 24-byte random value, a value in the range [0, 2^252-1] and the public key pk. In the SIKE API,
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// private keys are encoded in 434 octets in little endian format.
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// Public keys pk consist of 3 elements in GF(p503^2). In the SIKE API, pk is encoded in 378 octets.
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// Ciphertexts ct consist of the concatenation of a public key value and a 24-byte value. In the SIKE API, ct is encoded in 378 + 24 = 402 octets.
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// Shared keys ss consist of a value of 16 octets.
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/*********************** Ephemeral key exchange API ***********************/
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#define SIDH_SECRETKEYBYTES 32
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#define SIDH_PUBLICKEYBYTES 378
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#define SIDH_BYTES 126
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// SECURITY NOTE: SIDH supports ephemeral Diffie-Hellman key exchange. It is NOT secure to use it with static keys.
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// See "On the Security of Supersingular Isogeny Cryptosystems", S.D. Galbraith, C. Petit, B. Shani and Y.B. Ti, in ASIACRYPT 2016, 2016.
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// Extended version available at: http://eprint.iacr.org/2016/859
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// Generation of Alice's secret key
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// Outputs random value in [0, 2^250 - 1] to be used as Alice's private key
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void random_mod_order_A_SIDHp503(unsigned char* random_digits);
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// Generation of Bob's secret key
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// Outputs random value in [0, 2^Floor(Log(2,3^159)) - 1] to be used as Bob's private key
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void random_mod_order_B_SIDHp503(unsigned char* random_digits);
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// Alice's ephemeral public key generation
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// Input: a private key PrivateKeyA in the range [0, 2^250 - 1], stored in 32 bytes.
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// Output: the public key PublicKeyA consisting of 3 GF(p503^2) elements encoded in 378 bytes.
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int EphemeralKeyGeneration_A_SIDHp503(const unsigned char* PrivateKeyA, unsigned char* PublicKeyA);
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// Bob's ephemeral key-pair generation
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// It produces a private key PrivateKeyB and computes the public key PublicKeyB.
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// The private key is an integer in the range [0, 2^Floor(Log(2,3^159)) - 1], stored in 32 bytes.
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// The public key consists of 3 GF(p503^2) elements encoded in 378 bytes.
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int EphemeralKeyGeneration_B_SIDHp503(const unsigned char* PrivateKeyB, unsigned char* PublicKeyB);
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// Alice's ephemeral shared secret computation
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// It produces a shared secret key SharedSecretA using her secret key PrivateKeyA and Bob's public key PublicKeyB
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// Inputs: Alice's PrivateKeyA is an integer in the range [0, 2^250 - 1], stored in 32 bytes.
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// Bob's PublicKeyB consists of 3 GF(p503^2) elements encoded in 378 bytes.
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// Output: a shared secret SharedSecretA that consists of one element in GF(p503^2) encoded in 126 bytes.
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int EphemeralSecretAgreement_A_SIDHp503(const unsigned char* PrivateKeyA, const unsigned char* PublicKeyB, unsigned char* SharedSecretA);
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// Bob's ephemeral shared secret computation
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// It produces a shared secret key SharedSecretB using his secret key PrivateKeyB and Alice's public key PublicKeyA
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// Inputs: Bob's PrivateKeyB is an integer in the range [0, 2^Floor(Log(2,3^159)) - 1], stored in 32 bytes.
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// Alice's PublicKeyA consists of 3 GF(p503^2) elements encoded in 378 bytes.
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// Output: a shared secret SharedSecretB that consists of one element in GF(p503^2) encoded in 126 bytes.
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int EphemeralSecretAgreement_B_SIDHp503(const unsigned char* PrivateKeyB, const unsigned char* PublicKeyA, unsigned char* SharedSecretB);
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// Encoding of keys for KEX-based isogeny system "SIDHp503" (wire format):
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// ----------------------------------------------------------------------
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// Elements over GF(p503) are encoded in 63 octets in little endian format (i.e., the least significant octet is located in the lowest memory address).
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// Elements (a+b*i) over GF(p503^2), where a and b are defined over GF(p503), are encoded as {a, b}, with a in the lowest memory portion.
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//
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// Private keys PrivateKeyA and PrivateKeyB can have values in the range [0, 2^250-1] and [0, 2^252-1], resp. In the SIDH API, private keys are encoded
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// in 32 octets in little endian format.
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// Public keys PublicKeyA and PublicKeyB consist of 3 elements in GF(p503^2). In the SIDH API, they are encoded in 378 octets.
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// Shared keys SharedSecretA and SharedSecretB consist of one element in GF(p503^2). In the SIDH API, they are encoded in 126 octets.
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#endif
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BIN
msr/lib/intel/libsidh503.a
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BIN
msr/lib/intel/libsidh503.a
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Binary file not shown.
365
src/runner503.go
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365
src/runner503.go
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package main
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/*
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#cgo CFLAGS: -I../msr/include
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#cgo LDFLAGS: -L../msr/lib/intel -lsidh503 -lsidh751
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#include <P503_api.h>
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*/
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import "C"
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import "fmt"
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import rand "crypto/rand"
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import sidh "github.com/cloudflare/p751sidh/sidh"
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import sike "github.com/cloudflare/p751sidh/sike"
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import "unsafe"
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import "runtime"
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const (
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GSKsz = 24+32 // 56=(MSG+KeySize).
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CSKsz = 434 // 56+public key size, which MSR concatenates with secret key
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PKsz = 378
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CTsz = 24+378
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SSsz = 16
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)
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func FailNow() {
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pc := make([]uintptr, 10) // at least 1 entry needed
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runtime.Callers(2, pc)
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f := runtime.FuncForPC(pc[0])
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file, line := f.FileLine(pc[0])
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fmt.Printf("%s:%d %s\n", file, line, f.Name())
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panic(0)
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}
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// Helpers for byte convertion
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// ------------------------------
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// cBytes must be initialized to proper size
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func convBytesGoToC(goBytes []byte, cBytes []C.uchar) {
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for i,v:=range(goBytes) {
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cBytes[i] = C.uchar(v)
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}
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}
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// goBytes must be initialized to proper size
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func convBytesCToGo(cBytes []C.uchar, goBytes []byte) {
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copy(goBytes, C.GoBytes(unsafe.Pointer(&cBytes[0]), C.int(len(cBytes))))
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}
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// Helpers for key generation
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func keygenMsr() (*sidh.PublicKey, *sidh.PrivateKey) {
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var prvKey = sidh.NewPrivateKey(sidh.FP_503, sidh.KeyVariant_SIKE)
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var pubKey = sidh.NewPublicKey(sidh.FP_503, sidh.KeyVariant_SIKE)
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var msrPK [PKsz]C.uchar
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var msrSK [CSKsz]C.uchar
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if C.crypto_kem_keypair_SIKEp503(&msrPK[0], &msrSK[0]) != 0 {
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panic(0)
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}
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if prvKey.Import(C.GoBytes(unsafe.Pointer(&msrSK[0]), GSKsz)) != nil {
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panic(0)
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}
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if pubKey.Import(C.GoBytes(unsafe.Pointer(&msrPK[0]), PKsz)) != nil {
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panic(0)
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}
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return pubKey, prvKey
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}
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func keygenCf() (*sidh.PublicKey, *sidh.PrivateKey) {
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var prvKey = sidh.NewPrivateKey(sidh.FP_503, sidh.KeyVariant_SIKE)
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err := prvKey.Generate(rand.Reader)
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if err!=nil {
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fmt.Errorf("ERR: Generate private key for CF failed")
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}
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return prvKey.GeneratePublicKey(),prvKey
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}
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// MSR keygen
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// CF Encapsulate
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// MSR Decapsulate
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func test_msrK_cfE_msrD() {
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var cCT [CTsz]C.uchar
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var cSS [SSsz]C.uchar
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var cSK [CSKsz]C.uchar
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pubKey, prvKey := keygenMsr()
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gCT, gSS, err := sike.Encapsulate(rand.Reader, pubKey)
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if err != nil {
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panic(0)
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}
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convBytesGoToC(gCT, cCT[:])
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convBytesGoToC(prvKey.Export(), cSK[:])
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convBytesGoToC(pubKey.Export(), cSK[56:])
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if C.crypto_kem_dec_SIKEp503(&cSS[0], &cCT[0], &cSK[0]) != 0 {
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panic(0)
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}
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for i:=0; i<SSsz; i++ {
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if byte(cSS[i]) != gSS[i] {
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fmt.Println("ERR: shared secrets differ")
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FailNow()
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}
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}
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}
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// CF keygen
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// CF Encapsulate
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// MSR Decapsulate
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func test_cfK_cfE_msrD() {
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// C variables
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var cSS [SSsz]C.uchar
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var cCT [CTsz]C.uchar
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var cPK [PKsz]C.uchar
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var cSK [CSKsz]C.uchar
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pubKey, prvKey := keygenCf()
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convBytesGoToC(pubKey.Export(), cPK[:])
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gCT, gSS, err := sike.Encapsulate(rand.Reader, pubKey)
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if err != nil {
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panic("err: SIKE CF encapsulation")
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}
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convBytesGoToC(gCT[:], cCT[:])
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convBytesGoToC(prvKey.Export(), cSK[:])
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convBytesGoToC(pubKey.Export(), cSK[56:])
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if C.crypto_kem_dec_SIKEp503(&cSS[0], &cCT[0], &cSK[0]) != 0 {
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panic("Decapsulation failed")
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}
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for i,_:=range(gSS) {
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if gSS[i] != byte(cSS[i]) {
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fmt.Printf("LEN=%d %X\n", len(gSS), gSS)
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fmt.Printf("LEN=%d %X\n", len(cSS), cSS)
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fmt.Println("ERR: shared secrets differ")
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FailNow()
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}
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}
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}
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// Check if public key generated with CF is same as the one from MSR
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func test_cfK_msrK1() {
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// C variables
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var cPK [PKsz]C.uchar
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var cSK [CSKsz]C.uchar
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pubKey, prvKey := keygenCf()
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convBytesGoToC(prvKey.Export()[24:], cSK[:])
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if C.EphemeralKeyGeneration_B_SIDHp503(&cSK[0], &cPK[0]) != 0 {
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panic(0)
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}
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gPK := pubKey.Export()
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for i,v:=range(gPK) {
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if byte(cPK[i]) != v {
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fmt.Printf("Public key B differ")
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FailNow()
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}
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}
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}
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// Check if public key generated with CF is same as the one from MSR
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func test_cfK_msrK2() {
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pubKeyMsr, prvKey := keygenMsr()
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pubKeyCf := prvKey.GeneratePublicKey()
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cfPK := pubKeyCf.Export()
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msrPK := pubKeyMsr.Export()
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for i,v:=range(cfPK) {
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if msrPK[i]!= v {
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fmt.Printf("Public key B differ")
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FailNow()
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}
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}
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}
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// CF keygen
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// MSR Encapsulate
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// CF Decapsulate
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func test_cfK_msrE_cfD() {
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// C variables
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var cSS [SSsz]C.uchar
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var cCT [CTsz]C.uchar
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var cPK [PKsz]C.uchar
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// GO variables
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var gCT [CTsz]byte
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pubKey, prvKey := keygenCf()
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convBytesGoToC(pubKey.Export(), cPK[:])
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if C.crypto_kem_enc_SIKEp503(&cCT[0], &cSS[0], &cPK[0]) != 0 {
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panic(0)
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}
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convBytesCToGo(cCT[:], gCT[:])
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gSS, err := sike.Decapsulate(prvKey, pubKey, gCT[:])
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if err != nil {
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panic("Decapsulation failed")
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}
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for i,_:=range(gSS) {
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if gSS[i] != byte(cSS[i]) {
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fmt.Println("ERR: shared secrets differ")
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FailNow()
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}
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}
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}
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func test_cfK_msrE_msrD() {
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// C variables
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var cSS [SSsz]C.uchar
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var cSS2 [SSsz]C.uchar
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var cCT [CTsz]C.uchar
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var cPK [PKsz]C.uchar
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var cSK [CSKsz]C.uchar
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// GO variables
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pubKey, prvKey := keygenCf()
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convBytesGoToC(pubKey.Export(), cPK[:])
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if C.crypto_kem_enc_SIKEp503(&cCT[0], &cSS[0], &cPK[0]) != 0 {
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panic(0)
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}
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convBytesGoToC(prvKey.Export(), cSK[:])
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convBytesGoToC(pubKey.Export(), cSK[56:])
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if C.crypto_kem_dec_SIKEp503(&cSS2[0], &cCT[0], &cSK[0]) != 0 {
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panic(0)
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}
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for i,_:=range(cSS) {
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if cSS[i] != cSS2[i] {//gSS[i] != byte(cSS[i]) {
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fmt.Println("ERR: shared secrets differ")
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FailNow()
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}
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}
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}
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// MSR keygen
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// MSR Encapsulate
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// CF Decapsulate
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func test_msrK_msrE_cfD() {
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// C variables
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var cSS [SSsz]C.uchar
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var cCT [CTsz]C.uchar
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var cPK [PKsz]C.uchar
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var cSK [CSKsz]C.uchar
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var gCT [CTsz]byte
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// GO variables
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pubKey, prvKey := keygenMsr()
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convBytesGoToC(prvKey.Export(), cSK[:])
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convBytesGoToC(pubKey.Export(), cSK[56:])
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convBytesGoToC(pubKey.Export(), cPK[:])
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C.crypto_kem_enc_SIKEp503(&cCT[0], &cSS[0], &cPK[0])
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convBytesCToGo(cCT[:], gCT[:])
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gSS, err := sike.Decapsulate(prvKey, pubKey, gCT[:])
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if err!=nil {
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panic(0)
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}
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for i,_:=range(cSS) {
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if byte(cSS[i]) != gSS[i] {
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fmt.Println("ERR: shared secrets differ")
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FailNow()
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}
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}
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}
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// MSR keygen
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// CF Encapsulate
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// CF Decapsulate
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func test_msrK_cfE_cfD() {
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pubKey, prvKey := keygenMsr()
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gCT, gSS1, err := sike.Encapsulate(rand.Reader, pubKey)
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if err != nil {
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panic("err: SIKE CF encapsulation")
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}
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gSS2, err := sike.Decapsulate(prvKey, pubKey, gCT)
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if err!=nil || len(gSS1) != len(gSS2) {
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panic("Decapsulation failed")
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}
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for i,_:=range(gSS1) {
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if gSS1[i] != gSS2[i] {
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fmt.Printf("LEN=%d %X\n", len(gSS1), gSS1)
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fmt.Printf("LEN=%d %X\n", len(gSS2), gSS2)
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fmt.Println("ERR: shared secrets differ")
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FailNow()
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}
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}
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}
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// For CGO testing really
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// ----------------------
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func test_msrK_msrE_msrD() {
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// C variables
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var cSS [SSsz]C.uchar
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var cSS2 [SSsz]C.uchar
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var cCT [CTsz]C.uchar
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var cPK [PKsz]C.uchar
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var cSK [CSKsz]C.uchar
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// GO variables
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pubKey, prvKey := keygenMsr()
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convBytesGoToC(prvKey.Export(), cSK[:])
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convBytesGoToC(pubKey.Export(), cSK[56:])
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convBytesGoToC(pubKey.Export(), cPK[:])
|
||||
if C.crypto_kem_enc_SIKEp503(&cCT[0], &cSS[0], &cPK[0]) != 0 {panic(0)}
|
||||
if C.crypto_kem_dec_SIKEp503(&cSS2[0], &cCT[0], &cSK[0]) != 0 {panic(0)}
|
||||
|
||||
for i,_:=range(cSS) {
|
||||
if cSS[i] != cSS2[i] {
|
||||
fmt.Printf("LEN=%d %X\n", len(cSS2), cSS2)
|
||||
fmt.Printf("LEN=%d %X\n", len(cSS), cSS)
|
||||
fmt.Println("ERR: shared secrets differ")
|
||||
FailNow()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func debug() {
|
||||
fmt.Println("MSR+MSR+MSR")
|
||||
test_msrK_msrE_msrD()
|
||||
fmt.Println("CF+MSR+CF")
|
||||
test_cfK_msrE_cfD()
|
||||
fmt.Println("MSR+CF+MSR")
|
||||
test_msrK_cfE_msrD()
|
||||
fmt.Println("MSR+MSR+CF")
|
||||
test_msrK_msrE_cfD()
|
||||
fmt.Println("MSR+CF+CF")
|
||||
test_msrK_cfE_cfD()
|
||||
fmt.Println("CF+CF+MSR")
|
||||
test_cfK_cfE_msrD()
|
||||
fmt.Println("CF+MSR+MSR")
|
||||
test_cfK_msrE_msrD()
|
||||
fmt.Println("CF prv Keygen")
|
||||
test_cfK_msrK1()
|
||||
fmt.Println("MSR prv Keygen")
|
||||
test_cfK_msrK2()
|
||||
}
|
||||
|
||||
func doLongTest() {
|
||||
test_msrK_msrE_cfD()
|
||||
test_msrK_cfE_msrD()
|
||||
test_msrK_cfE_cfD()
|
||||
|
||||
test_cfK_msrE_cfD()
|
||||
test_cfK_cfE_msrD()
|
||||
test_cfK_msrE_msrD()
|
||||
|
||||
test_cfK_msrK1()
|
||||
test_cfK_msrK2()
|
||||
|
||||
test_msrK_msrE_msrD()
|
||||
}
|
||||
|
||||
func main() {
|
||||
debug()
|
||||
for i:=0; i<1000; i++ {
|
||||
doLongTest()
|
||||
}
|
||||
}
|
||||
|
||||
@ -2,7 +2,7 @@ package main
|
||||
|
||||
/*
|
||||
#cgo CFLAGS: -I../msr/include
|
||||
#cgo LDFLAGS: -L../msr/lib -lsidh751
|
||||
#cgo LDFLAGS: -L../msr/lib/intel -lsidh751
|
||||
#include <P751_api.h>
|
||||
*/
|
||||
import "C"
|
||||
Loading…
Reference in New Issue
Block a user