Add secp256k1-zkp and schnorrsig modules

.gitignore

@@ -0,0 +1,2 @@
+/target
+**/*.rs.bk

Cargo.toml

@@ -0,0 +1,6 @@
+[workspace]
+members = [
+    "secp256k1-zkp-dev",
+    "secp256k1-zkp-sys",
+    "secp256k1-zkp"
+]

contrib/test.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+if [ -z "$1" ]; then
+  echo This test script runs the workspace tests and the -sys tests with the
+  echo serde feature enabled. This is necessary because you can not test
+  echo features on the workspace level. The script also checks if the files are
+  echo rustfmt\'d.
+  echo
+  echo "ERROR: \$1 parameter must be the workspace directory"
+  exit 1
+fi
+DIR=$1
+
+shopt -s globstar
+
+(
+    cd "$DIR"
+    set -e
+    cargo test
+    (
+        cd secp256k1-zkp-sys
+        cargo test --features serde
+    )
+    rustfmt --check -- **/*.rs
+)
+
+if [ $? -ne 0 ]; then
+    echo ERROR: $0 failed
+    exit 1
+fi
+

contrib/vendor-libsecp-zkp.sh

@@ -0,0 +1,38 @@
+#!/bin/bash
+set -e
+
+
+if [ -z "$1" ]; then
+  echo "\$1 parameter must be the rust-secp256k1-zkp-sys depend directory"
+  echo "\$2 parameter (optional) can be the revision to check out"
+  exit 1
+fi
+
+PARENT_DIR=$1
+REV=$2
+DIR=secp256k1-zkp
+
+while true; do
+    read -r -p "$PARENT_DIR/$DIR will be deleted [yn]: " yn
+    case $yn in
+        [Yy]* ) break;;
+        [Nn]* ) exit;;
+        * ) echo "Please answer yes or no.";;
+    esac
+done
+
+cd "$PARENT_DIR"
+rm -rf "$DIR"
+git clone [email protected]:ElementsProject/secp256k1-zkp.git
+cd "$DIR"
+if [ -n "$REV" ]; then
+    git checkout "$REV"
+fi
+HEAD=$(git rev-parse HEAD)
+cd ..
+echo "\# This file was automatically created by $0" > ./secp256k1-zkp-HEAD-revision.txt
+echo "$HEAD" >> ./secp256k1-zkp-HEAD-revision.txt
+
+find "$DIR" -not -path '*/\.*' -type f -print0 | xargs -0 sed -i '/^#include/! s/secp256k1_/secp256k1_zkp_/g'
+# TODO: can be removed once 496c5b43b lands in secp-zkp
+find "$DIR" -not -path '*/\.*' -type f -print0 | xargs -0 sed -i 's/^const int CURVE_B/static const int CURVE_B/g'

secp256k1-zkp-dev/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "secp256k1-zkp-dev"
+version = "0.1.0"
+authors = ["Jonas Nick <[email protected]>"]
+
+license = "CC0-1.0"
+homepage = "https://github.com/ElementsProject/rust-secp256k1-zkp/"
+repository = "https://github.com/ElementsProject/rust-secp256k1-zkp/"
+description = "dev-dependencies for secp256k1-zkp-sys and secp256k1-zkp."
+keywords = [ "crypto", "ECDSA", "Schnorr", "secp256k1", "libsecp256k1", "secp256k1-zkp", "libsecp256k1-zkp", "bitcoin" ]
+
+[dependencies]
+rand = "0.6"
+
+[dependencies.secp256k1]
+version = "0.13"

secp256k1-zkp-dev/src/lib.rs

@@ -0,0 +1,60 @@
+// secp256k1-zkp bindings
+// Written in 2019 by
+//   Jonas Nick
+//
+// To the extent possible under law, the author(s) have dedicated all
+// copyright and related and neighboring rights to this software to
+// the public domain worldwide. This software is distributed without
+// any warranty.
+//
+// You should have received a copy of the CC0 Public Domain Dedication
+// along with this software.
+// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
+//
+
+/// The functions in this module are copied from secp256k1 because they can only be used when
+/// compiled with the `rand` feature. But the other libraries need them as a dev-dependency for
+/// `cargo test` also when `rand` is not enabled. Currently with cargo we can't have a `rand`
+/// dev-dependency and a non-`rand` dependency at the same time (see
+/// https://github.com/rust-lang/cargo/issues/1796).
+pub extern crate rand;
+pub extern crate secp256k1;
+
+use rand::Rng;
+use secp256k1::{PublicKey, Secp256k1, SecretKey, Signing};
+
+fn random_32_bytes<R: Rng>(rng: &mut R) -> [u8; 32] {
+    let mut ret = [0u8; 32];
+    rng.fill_bytes(&mut ret);
+    ret
+}
+
+trait NewSecretKey {
+    fn new<R: Rng>(rng: &mut R) -> SecretKey;
+}
+
+impl NewSecretKey for SecretKey {
+    /// Creates a new random secret key.
+    #[inline]
+    fn new<R: Rng>(rng: &mut R) -> SecretKey {
+        loop {
+            if let Ok(key) = SecretKey::from_slice(&random_32_bytes(rng)) {
+                return key;
+            }
+        }
+    }
+}
+
+pub trait GenerateKeypair {
+    /// Generates a random keypair.
+    fn generate_keypair<R: Rng>(&self, rng: &mut R) -> (SecretKey, PublicKey);
+}
+
+impl<C: Signing> GenerateKeypair for Secp256k1<C> {
+    #[inline]
+    fn generate_keypair<R: Rng>(&self, rng: &mut R) -> (SecretKey, PublicKey) {
+        let sk = SecretKey::new(rng);
+        let pk = PublicKey::from_secret_key(self, &sk);
+        (sk, pk)
+    }
+}