Merge pull request #29 from str4d/zip32

ZIP 32 APIs

Cargo.toml

@@ -29,6 +29,10 @@ rev = "7a5b5fc99ae483a0043db7547fb79a6fa44b88a9"
 git = "https://github.com/zcash-hackworks/sapling-crypto"
 rev = "21084bde2019c04bd34208e63c3560fe2c02fb0e"
 
+[dependencies.zip32]
+git = "https://github.com/zcash-hackworks/zip32"
+rev = "176470ef41583b5bd0bd749bd1b61d417aa8ec79"
+
 [profile.release]
 lto = true
 panic = 'abort'

include/librustzcash.h

@@ -270,6 +270,35 @@ extern "C" {
  uint64_t vpub_old,
  uint64_t vpub_new
  );
+
+ /// Derive the master ExtendedSpendingKey from a seed.
+ void librustzcash_zip32_xsk_master(
+ const unsigned char *seed,
+ size_t seedlen,
+ unsigned char *xsk_master
+ );
+
+ /// Derive a child ExtendedSpendingKey from a parent.
+ void librustzcash_zip32_xsk_derive(
+ const unsigned char *xsk_parent,
+ uint32_t i,
+ unsigned char *xsk_i
+ );
+
+ /// Derive a child ExtendedFullViewingKey from a parent.
+ bool librustzcash_zip32_xfvk_derive(
+ const unsigned char *xfvk_parent,
+ uint32_t i,
+ unsigned char *xfvk_i
+ );
+
+ /// Derive a PaymentAddress from an ExtendedFullViewingKey.
+ bool librustzcash_zip32_xfvk_address(
+ const unsigned char *xfvk,
+ const unsigned char *j,
+ unsigned char *j_ret,
+ unsigned char *addr_ret
+ );
 }
 
 #endif // LIBRUSTZCASH_INCLUDE_H_

src/rustzcash.rs

@@ -5,23 +5,28 @@ extern crate libc;
 extern crate pairing;
 extern crate rand;
 extern crate sapling_crypto;
+extern crate zip32;
 
 mod hashreader;
 
 #[macro_use]
 extern crate lazy_static;
 
 use pairing::{
- bls12_381::{Bls12, Fr, FrRepr}, BitIterator, Field, PrimeField, PrimeFieldRepr,
+ bls12_381::{Bls12, Fr, FrRepr},
+ BitIterator, Field, PrimeField, PrimeFieldRepr,
 };
 
 use sapling_crypto::{
- circuit::multipack, constants::CRH_IVK_PERSONALIZATION,
+ circuit::multipack,
+ constants::CRH_IVK_PERSONALIZATION,
  jubjub::{
- edwards, fs::{Fs, FsRepr}, FixedGenerators, JubjubBls12, JubjubEngine, JubjubParams,
- PrimeOrder, ToUniform, Unknown,
+ edwards,
+ fs::{Fs, FsRepr},
+ FixedGenerators, JubjubBls12, JubjubEngine, JubjubParams, PrimeOrder, ToUniform, Unknown,
  },
- pedersen_hash::{pedersen_hash, Personalization}, redjubjub::{self, Signature},
+ pedersen_hash::{pedersen_hash, Personalization},
+ redjubjub::{self, Signature},
 };
 
 use sapling_crypto::circuit::sprout::{self, TREE_DEPTH as SPROUT_TREE_DEPTH};
@@ -1563,3 +1568,86 @@ pub extern "system" fn librustzcash_sapling_proving_ctx_init() -> *mut SaplingPr
 pub extern "system" fn librustzcash_sapling_proving_ctx_free(ctx: *mut SaplingProvingContext) {
  drop(unsafe { Box::from_raw(ctx) });
 }
+
+#[no_mangle]
+pub extern "system" fn librustzcash_zip32_xsk_master(
+ seed: *const c_uchar,
+ seedlen: size_t,
+ xsk_master: *mut [c_uchar; 169],
+) {
+ let seed = unsafe { std::slice::from_raw_parts(seed, seedlen) };
+
+ let xsk = zip32::ExtendedSpendingKey::master(seed);
+
+ xsk.write(&mut (unsafe { &mut *xsk_master })[..])
+ .expect("should be able to serialize an ExtendedSpendingKey");
+}
+
+#[no_mangle]
+pub extern "system" fn librustzcash_zip32_xsk_derive(
+ xsk_parent: *const [c_uchar; 169],
+ i: uint32_t,
+ xsk_i: *mut [c_uchar; 169],
+) {
+ let xsk_parent = zip32::ExtendedSpendingKey::read(&unsafe { *xsk_parent }[..])
+ .expect("valid ExtendedSpendingKey");
+ let i = zip32::ChildIndex::from_index(i);
+
+ let xsk = xsk_parent.derive_child(i);
+
+ xsk.write(&mut (unsafe { &mut *xsk_i })[..])
+ .expect("should be able to serialize an ExtendedSpendingKey");
+}
+
+#[no_mangle]
+pub extern "system" fn librustzcash_zip32_xfvk_derive(
+ xfvk_parent: *const [c_uchar; 169],
+ i: uint32_t,
+ xfvk_i: *mut [c_uchar; 169],
+) -> bool {
+ let xfvk_parent = zip32::ExtendedFullViewingKey::read(&unsafe { *xfvk_parent }[..])
+ .expect("valid ExtendedFullViewingKey");
+ let i = zip32::ChildIndex::from_index(i);
+
+ let xfvk = match xfvk_parent.derive_child(i) {
+ Ok(xfvk) => xfvk,
+ Err(_) => return false,
+ };
+
+ xfvk.write(&mut (unsafe { &mut *xfvk_i })[..])
+ .expect("should be able to serialize an ExtendedFullViewingKey");
+
+ true
+}
+
+#[no_mangle]
+pub extern "system" fn librustzcash_zip32_xfvk_address(
+ xfvk: *const [c_uchar; 169],
+ j: *const [c_uchar; 11],
+ j_ret: *mut [c_uchar; 11],
+ addr_ret: *mut [c_uchar; 43],
+) -> bool {
+ let xfvk = zip32::ExtendedFullViewingKey::read(&unsafe { *xfvk }[..])
+ .expect("valid ExtendedFullViewingKey");
+ let j = zip32::DiversifierIndex(unsafe { *j });
+
+ let addr = match xfvk.address(j) {
+ Ok(addr) => addr,
+ Err(_) => return false,
+ };
+
+ let j_ret = unsafe { &mut *j_ret };
+ let addr_ret = unsafe { &mut *addr_ret };
+
+ j_ret.copy_from_slice(&(addr.0).0);
+ addr_ret
+ .get_mut(..11)
+ .unwrap()
+ .copy_from_slice(&addr.1.diversifier.0);
+ addr.1
+ .pk_d
+ .write(addr_ret.get_mut(11..).unwrap())
+ .expect("should be able to serialize a PaymentAddress");
+
+ true
+}

src/tests/signatures.rs

@@ -1,6 +1,7 @@
 use pairing::{bls12_381::Bls12, PrimeField, PrimeFieldRepr};
 use sapling_crypto::{
- jubjub::{FixedGenerators, JubjubEngine}, redjubjub::{PrivateKey, PublicKey, Signature},
+ jubjub::{FixedGenerators, JubjubEngine},
+ redjubjub::{PrivateKey, PublicKey, Signature},
 };
 
 use super::JUBJUB;