Merge rust-bitcoin#528: Backport of multi_a bug fix

850bd2e Fix Ci (sanket1729)
4797f99 Release 9.0.1 (sanket1729)
cd9de92 Update multi_a to not include n wrapper (sanket1729)

Pull request description:

ACKs for top commit:
  apoelstra:
    ACK 850bd2e

Tree-SHA512: 95e9e134f90e91c16bdf11f67a30047da61db143148d0cc1eb072864a07c27e2295ee4b44a5c0eb940e4cd8b71db7a1ebf2efb283f615b2800f25f1a42bdc252

Author: apoelstra

CHANGELOG.md

@@ -1,3 +1,11 @@
+# 9.0.1 - March 8, 2023
+
+- Fixed a typing rule in `multi_a` for taproot miniscript descriptors. Current typing rules
+incorrectly tagged `multi_a` with the `n` property. Certain miniscripts of the form `j:multi_a` could
+could not spent without the first key. We could not find any evidence of these scripts being used
+in the wild. While this is technically a breaking change, any downstream users whose code would
+break by this change are already vulnerable.
+
 # 9.0.0 - November 5, 2022
 
 - Fixed a bug dealing with dissatisfying pkh inside thresh

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "miniscript"
-version = "9.0.0"
+version = "9.0.1"
 authors = ["Andrew Poelstra <[email protected]>, Sanket Kanjalkar <[email protected]>"]
 license = "CC0-1.0"
 homepage = "https://github.com/rust-bitcoin/rust-miniscript/"

contrib/test.sh

@@ -25,6 +25,7 @@ if [ "$MSRV" = true ]; then
     cargo update -p url --precise 2.2.2
     cargo update -p form_urlencoded --precise 1.0.1
     cargo update -p once_cell --precise 1.13.1
+    cargo update -p syn --precise 1.0.107
 fi
 
 # Format if told to

src/miniscript/types/correctness.rs

@@ -170,6 +170,15 @@ impl Property for Correctness {
         }
     }
 
+    fn from_multi_a(_: usize, _: usize) -> Self {
+        Correctness {
+            base: Base::B,
+            input: Input::Any,
+            dissatisfiable: true,
+            unit: true,
+        }
+    }
+
     fn from_hash() -> Self {
         Correctness {
             base: Base::B,

src/miniscript/types/malleability.rs

@@ -119,6 +119,14 @@ impl Property for Malleability {
         }
     }
 
+    fn from_multi_a(_: usize, _: usize) -> Self {
+        Malleability {
+            dissat: Dissat::Unique,
+            safe: true,
+            non_malleable: true,
+        }
+    }
+
     fn from_hash() -> Self {
         Malleability {
             dissat: Dissat::Unknown,

src/miniscript/types/mod.rs

@@ -267,10 +267,7 @@ pub trait Property: Sized {
     fn from_multi(k: usize, n: usize) -> Self;
 
     /// Type property of a `MultiA` fragment
-    fn from_multi_a(k: usize, n: usize) -> Self {
-        // default impl same as multi
-        Self::from_multi(k, n)
-    }
+    fn from_multi_a(k: usize, n: usize) -> Self;
 
     /// Type property of a hash fragment
     fn from_hash() -> Self;
@@ -583,6 +580,13 @@ impl Property for Type {
         }
     }
 
+    fn from_multi_a(k: usize, n: usize) -> Self {
+        Type {
+            corr: Property::from_multi_a(k, n),
+            mall: Property::from_multi_a(k, n),
+        }
+    }
+
     fn from_hash() -> Self {
         Type {
             corr: Property::from_hash(),