Merge pull request #22 from TheBlueMatt/main

[ldk-c-bindings] / lightning-c-bindings / src / c_types / mod.rs

diff --git a/lightning-c-bindings/src/c_types/mod.rs b/lightning-c-bindings/src/c_types/mod.rs
index cd96dffe1969bbe6c845fcfa0ff2ec73e64dff4a..6267b80bc2dd007ba9476f76d01127d2b9a74937 100644 (file)
--- a/lightning-c-bindings/src/c_types/mod.rs
+++ b/lightning-c-bindings/src/c_types/mod.rs
@@ -9,6 +9,8 @@ use bitcoin::secp256k1::key::PublicKey as SecpPublicKey;
 use bitcoin::secp256k1::key::SecretKey as SecpSecretKey;
 use bitcoin::secp256k1::Signature as SecpSignature;
 use bitcoin::secp256k1::Error as SecpError;
+use bitcoin::secp256k1::recovery::RecoveryId;
+use bitcoin::secp256k1::recovery::RecoverableSignature as SecpRecoverableSignature;
 use bitcoin::bech32;
 
 use std::convert::TryInto; // Bindings need at least rustc 1.34
@@ -85,6 +87,32 @@ impl Signature {
        #[allow(unused)] pub(crate) fn null() -> Self { Self { compact_form: [0; 64] } }
 }
 
+#[repr(C)]
+#[derive(Clone)]
+/// Represents a secp256k1 signature serialized as two 32-byte numbers as well as a tag which
+/// allows recovering the exact public key which created the signature given the message.
+pub struct RecoverableSignature {
+       /// The bytes of the signature in "compact" form plus a "Recovery ID" which allows for
+       /// recovery.
+       pub serialized_form: [u8; 68],
+}
+impl RecoverableSignature {
+       pub(crate) fn from_rust(pk: &SecpRecoverableSignature) -> Self {
+               let (id, compact_form) = pk.serialize_compact();
+               let mut serialized_form = [0; 68];
+               serialized_form[0..64].copy_from_slice(&compact_form[..]);
+               serialized_form[64..].copy_from_slice(&id.to_i32().to_le_bytes());
+               Self { serialized_form }
+       }
+       pub(crate) fn into_rust(&self) -> SecpRecoverableSignature {
+               let mut id = [0; 4];
+               id.copy_from_slice(&self.serialized_form[64..]);
+               SecpRecoverableSignature::from_compact(&self.serialized_form[0..64],
+                               RecoveryId::from_i32(i32::from_le_bytes(id)).expect("Invalid Recovery ID"))
+                       .unwrap()
+       }
+}
+
 #[repr(C)]
 /// Represents an error returned from libsecp256k1 during validation of some secp256k1 data
 pub enum Secp256k1Error {
@@ -354,11 +382,27 @@ impl Into<Str> for &'static str {
                Str { chars: self.as_ptr(), len: self.len(), chars_is_owned: false }
        }
 }
-impl Into<&'static str> for Str {
-       fn into(self) -> &'static str {
+impl Str {
+       pub(crate) fn into_str(&self) -> &'static str {
                if self.len == 0 { return ""; }
                std::str::from_utf8(unsafe { std::slice::from_raw_parts(self.chars, self.len) }).unwrap()
        }
+       pub(crate) fn into_string(mut self) -> String {
+               let bytes = if self.len == 0 {
+                       Vec::new()
+               } else if self.chars_is_owned {
+                       let ret = unsafe {
+                               Box::from_raw(std::slice::from_raw_parts_mut(unsafe { self.chars as *mut u8 }, self.len))
+                       }.into();
+                       self.chars_is_owned = false;
+                       ret
+               } else {
+                       let mut ret = Vec::with_capacity(self.len);
+                       ret.extend_from_slice(unsafe { std::slice::from_raw_parts(self.chars, self.len) });
+                       ret
+               };
+               String::from_utf8(bytes).unwrap()
+       }
 }
 impl Into<Str> for String {
        fn into(self) -> Str {