From cac78151935e83a0cd0eb58da0cca175e8e4ba4e Mon Sep 17 00:00:00 2001
From: SarcasticNastik <aman.rojjha@research.iiit.ac.in>
Date: Tue, 13 Jul 2021 19:10:04 +0530
Subject: [PATCH 1/2] Add absolute timelocks
---
src/policy/semantic.rs | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/src/policy/semantic.rs b/src/policy/semantic.rs
index 740c493a7..b8a261622 100644
--- a/src/policy/semantic.rs
+++ b/src/policy/semantic.rs
@@ -499,6 +499,34 @@ impl<Pk: MiniscriptKey> Policy<Pk> {
ret
}
+ /// Helper function for recursion in `absolute timelocks`
+ pub fn real_absolute_timelocks(&self) -> Vec<u32> {
+ match *self {
+ Policy::Unsatisfiable
+ | Policy::Trivial
+ | Policy::KeyHash(..)
+ | Policy::Sha256(..)
+ | Policy::Hash256(..)
+ | Policy::Ripemd160(..)
+ | Policy::Hash160(..) => vec![],
+ Policy::Older(..) => vec![],
+ Policy::After(t) => vec![t],
+ Policy::Threshold(_, ref subs) => subs.iter().fold(vec![], |mut acc, x| {
+ acc.extend(x.real_absolute_timelocks());
+ acc
+ }),
+ }
+ }
+
+ /// Returns a list of all absolute timelocks, not including 0,
+ /// which appear in the policy
+ pub fn absolute_timelocks(&self) -> Vec<u32> {
+ let mut ret = self.real_absolute_timelocks();
+ ret.sort();
+ ret.dedup();
+ ret
+ }
+
/// Filter a policy by eliminating relative timelock constraints
/// that are not satisfied at the given age.
pub fn at_age(mut self, time: u32) -> Policy<Pk> {
@@ -604,6 +632,7 @@ mod tests {
let policy = StringPolicy::from_str("pkh()").unwrap();
assert_eq!(policy, Policy::KeyHash("".to_owned()));
assert_eq!(policy.relative_timelocks(), vec![]);
+ assert_eq!(policy.absolute_timelocks(), vec![]);
assert_eq!(policy.clone().at_age(0), policy.clone());
assert_eq!(policy.clone().at_age(10000), policy.clone());
assert_eq!(policy.n_keys(), 1);
@@ -611,6 +640,7 @@ mod tests {
let policy = StringPolicy::from_str("older(1000)").unwrap();
assert_eq!(policy, Policy::Older(1000));
+ assert_eq!(policy.absolute_timelocks(), vec![]);
assert_eq!(policy.relative_timelocks(), vec![1000]);
assert_eq!(policy.clone().at_age(0), Policy::Unsatisfiable);
assert_eq!(policy.clone().at_age(999), Policy::Unsatisfiable);
From 925ae345c51769c9ff0da7908f26f90866cf5c52 Mon Sep 17 00:00:00 2001
From: SarcasticNastik <aman.rojjha@research.iiit.ac.in>
Date: Tue, 13 Jul 2021 19:31:22 +0530
Subject: [PATCH 2/2] Add `at_height` for policy analysis
---
src/policy/semantic.rs | 33 ++++++++++++++++++++++++++++++++-
1 file changed, 32 insertions(+), 1 deletion(-)
diff --git a/src/policy/semantic.rs b/src/policy/semantic.rs
index b8a261622..6f18300a0 100644
--- a/src/policy/semantic.rs
+++ b/src/policy/semantic.rs
@@ -500,7 +500,7 @@ impl<Pk: MiniscriptKey> Policy<Pk> {
}
/// Helper function for recursion in `absolute timelocks`
- pub fn real_absolute_timelocks(&self) -> Vec<u32> {
+ fn real_absolute_timelocks(&self) -> Vec<u32> {
match *self {
Policy::Unsatisfiable
| Policy::Trivial
@@ -546,6 +546,25 @@ impl<Pk: MiniscriptKey> Policy<Pk> {
self.normalized()
}
+ /// Filter a policy by eliminating absolute timelock constraints
+ /// that are not satisfied at the given age.
+ pub fn at_height(mut self, time: u32) -> Policy<Pk> {
+ self = match self {
+ Policy::After(t) => {
+ if t > time {
+ Policy::Unsatisfiable
+ } else {
+ Policy::After(t)
+ }
+ }
+ Policy::Threshold(k, subs) => {
+ Policy::Threshold(k, subs.into_iter().map(|sub| sub.at_height(time)).collect())
+ }
+ x => x,
+ };
+ self.normalized()
+ }
+
/// Count the number of public keys and keyhashes referenced in a policy.
/// Duplicate keys will be double-counted.
pub fn n_keys(&self) -> usize {
@@ -658,6 +677,7 @@ mod tests {
)
);
assert_eq!(policy.relative_timelocks(), vec![1000]);
+ assert_eq!(policy.absolute_timelocks(), vec![]);
assert_eq!(policy.clone().at_age(0), Policy::KeyHash("".to_owned()));
assert_eq!(policy.clone().at_age(999), Policy::KeyHash("".to_owned()));
assert_eq!(policy.clone().at_age(1000), policy.clone().normalized());
@@ -688,6 +708,17 @@ mod tests {
policy.relative_timelocks(),
vec![1000, 2000, 10000] //sorted and dedup'd
);
+
+ let policy = StringPolicy::from_str("after(1000)").unwrap();
+ assert_eq!(policy, Policy::After(1000));
+ assert_eq!(policy.absolute_timelocks(), vec![1000]);
+ assert_eq!(policy.relative_timelocks(), vec![]);
+ assert_eq!(policy.clone().at_height(0), Policy::Unsatisfiable);
+ assert_eq!(policy.clone().at_height(999), Policy::Unsatisfiable);
+ assert_eq!(policy.clone().at_height(1000), policy.clone());
+ assert_eq!(policy.clone().at_height(10000), policy.clone());
+ assert_eq!(policy.n_keys(), 0);
+ assert_eq!(policy.minimum_n_keys(), 0);
}
#[test]