async_hwi/
utils.rs

1use std::{cmp::Ordering, collections::BTreeMap, str::FromStr};
2
3use bitcoin::{
4    bip32::{ChildNumber, DerivationPath, KeySource},
5    psbt::Psbt,
6    secp256k1::PublicKey,
7};
8
9use crate::{Error, HWI};
10
11pub struct Bip32DerivationFilter<'a> {
12    psbt: &'a mut Psbt,
13    ignored_bip32_derivations: Vec<BTreeMap<PublicKey, KeySource>>,
14}
15
16impl<'a> Bip32DerivationFilter<'a> {
17    pub fn new(psbt: &'a mut Psbt) -> Self {
18        Self {
19            ignored_bip32_derivations: psbt.inputs.iter().map(|_| BTreeMap::new()).collect(),
20            psbt,
21        }
22    }
23    // Bitbox and Coldcard sign with the first bip32_derivation that matches its fingerprint.
24    // In order to to multiple round of signing the bip32_derivation of keys that
25    // signed the psbt must be removed then appended once the tx is signed.
26    pub fn ignore_signed_key_derivation(mut self) -> Self {
27        for (i, input) in self.psbt.inputs.iter_mut().enumerate() {
28            for key in input.partial_sigs.keys() {
29                if let Some(derivation) = input.bip32_derivation.remove(&key.inner) {
30                    self.ignored_bip32_derivations[i].insert(key.inner, derivation);
31                }
32            }
33        }
34        self
35    }
36
37    // Input may have multiple derivation with the same fingerprint and different derivation
38    // for example:
39    // Input A: fg/0/0, fg/1/0 and Input B fg/0/1, fg/1/1.
40    // We want for this first round of signature to have A: fg/0/0 and fg/0/1
41    pub fn ignore_same_fg_bip32_derivations(mut self) -> Self {
42        let mut priority_order = Vec::<KeySource>::new();
43        for input in &self.psbt.inputs {
44            for source in input.bip32_derivation.values() {
45                priority_order.push(source.clone());
46            }
47        }
48        priority_order.sort_by(|(fg1, path1), (fg2, path2)| match fg1.cmp(fg2) {
49            Ordering::Less => Ordering::Less,
50            Ordering::Greater => Ordering::Greater,
51            Ordering::Equal => path2.cmp(path1),
52        });
53
54        for (i, input) in self.psbt.inputs.iter_mut().enumerate() {
55            let mut to_remove = Vec::<PublicKey>::new();
56            for (key1, source1) in &input.bip32_derivation {
57                for (key2, source2) in &input.bip32_derivation {
58                    if source1.0 == source2.0 && source1.1 != source2.1 {
59                        if priority_order.iter().position(|s| s == source1)
60                            < priority_order.iter().position(|s| s == source2)
61                        {
62                            to_remove.push(*key2);
63                        } else {
64                            to_remove.push(*key1);
65                        }
66                    }
67                }
68            }
69            for key in to_remove {
70                if let Some(derivation) = input.bip32_derivation.remove(&key) {
71                    self.ignored_bip32_derivations[i].insert(key, derivation);
72                }
73            }
74        }
75
76        self
77    }
78
79    /// Signs the psbt with the HWI interface and puts back the ignored bip32 derivations
80    pub async fn sign_psbt<T: HWI>(mut self, device: &T) -> Result<(), Error> {
81        device.sign_tx(self.psbt).await?;
82
83        for (i, input) in self.psbt.inputs.iter_mut().enumerate() {
84            input
85                .bip32_derivation
86                .append(&mut self.ignored_bip32_derivations[i]);
87        }
88
89        Ok(())
90    }
91}
92
93pub fn merge_signatures(psbt: &mut Psbt, signed_psbt: &Psbt) {
94    for i in 0..signed_psbt.inputs.len() {
95        let psbtin = match psbt.inputs.get_mut(i) {
96            Some(psbtin) => psbtin,
97            None => continue,
98        };
99        let signed_psbtin = match signed_psbt.inputs.get(i) {
100            Some(signed_psbtin) => signed_psbtin,
101            None => continue,
102        };
103        psbtin
104            .partial_sigs
105            .extend(&mut signed_psbtin.partial_sigs.iter());
106        psbtin
107            .tap_script_sigs
108            .extend(&mut signed_psbtin.tap_script_sigs.iter());
109        if let Some(sig) = signed_psbtin.tap_key_sig {
110            psbtin.tap_key_sig = Some(sig);
111        }
112    }
113}
114
115pub fn bip86_path_child_numbers(path: DerivationPath) -> Result<Vec<ChildNumber>, Error> {
116    let children: Vec<ChildNumber> = path.into();
117    if children.len() != 5
118        || children[0] != ChildNumber::from_hardened_idx(86).unwrap()
119        || children[1].is_normal()
120        || children[2].is_normal()
121        || children[3].is_hardened()
122        || children[4].is_hardened()
123    {
124        Err(Error::InvalidParameter(
125            "derivation_path",
126            "path is not bip86 compatible".to_string(),
127        ))
128    } else {
129        Ok(children)
130    }
131}
132
133#[cfg(feature = "regex")]
134pub fn extract_keys_and_template<T: FromStr>(policy: &str) -> Result<(String, Vec<T>), Error> {
135    let re = regex::Regex::new(r"((\[.+?\])?[xyYzZtuUvV]pub[1-9A-HJ-NP-Za-km-z]{79,108})").unwrap();
136    let mut descriptor_template = policy.to_string();
137    let mut pubkeys_str: Vec<&str> = Vec::new();
138    for capture in re.find_iter(policy) {
139        if !pubkeys_str.contains(&capture.as_str()) {
140            pubkeys_str.push(capture.as_str());
141        }
142    }
143
144    let mut pubkeys: Vec<T> = Vec::new();
145    for (i, key_str) in pubkeys_str.iter().enumerate() {
146        descriptor_template = descriptor_template.replace(key_str, &format!("@{}", i));
147        let pubkey = T::from_str(key_str).map_err(|_| Error::UnsupportedInput)?;
148        pubkeys.push(pubkey);
149    }
150
151    // Do not include the hash in the descriptor template.
152    if let Some((descriptor_template, _hash)) = descriptor_template.rsplit_once('#') {
153        Ok((descriptor_template.to_string(), pubkeys))
154    } else {
155        Ok((descriptor_template, pubkeys))
156    }
157}
158
159#[cfg(test)]
160mod tests {
161    use std::str::FromStr;
162
163    use super::*;
164
165    #[test]
166    fn test_sort_bip32_derivations() {
167        let mut psbt = Psbt::from_str("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").unwrap();
168        assert_eq!(psbt.inputs[0].bip32_derivation.len(), 6);
169        assert_eq!(psbt.inputs[1].bip32_derivation.len(), 6);
170        let filter = Bip32DerivationFilter::new(&mut psbt).ignore_same_fg_bip32_derivations();
171        assert_eq!(filter.ignored_bip32_derivations[0].len(), 4);
172        assert_eq!(filter.ignored_bip32_derivations[1].len(), 4);
173        assert_eq!(psbt.inputs[0].bip32_derivation.len(), 2);
174        assert_eq!(psbt.inputs[1].bip32_derivation.len(), 2);
175    }
176
177    #[test]
178    fn test_extract_keys_and_template() {
179        let res = extract_keys_and_template::<String>("wsh(or_d(pk([f5acc2fd/49'/1'/0']tpubDCbK3Ysvk8HjcF6mPyrgMu3KgLiaaP19RjKpNezd8GrbAbNg6v5BtWLaCt8FNm6QkLseopKLf5MNYQFtochDTKHdfgG6iqJ8cqnLNAwtXuP/**),and_v(v:pkh(tpubDDtb2WPYwEWw2WWDV7reLV348iJHw2HmhzvPysKKrJw3hYmvrd4jasyoioVPdKGQqjyaBMEvTn1HvHWDSVqQ6amyyxRZ5YjpPBBGjJ8yu8S/**),older(100))))").unwrap();
180        assert_eq!(res.0, "wsh(or_d(pk(@0/**),and_v(v:pkh(@1/**),older(100))))");
181        assert_eq!(res.1.len(), 2);
182        assert_eq!(res.1[0], "[f5acc2fd/49'/1'/0']tpubDCbK3Ysvk8HjcF6mPyrgMu3KgLiaaP19RjKpNezd8GrbAbNg6v5BtWLaCt8FNm6QkLseopKLf5MNYQFtochDTKHdfgG6iqJ8cqnLNAwtXuP".to_string());
183        assert_eq!(res.1[1], "tpubDDtb2WPYwEWw2WWDV7reLV348iJHw2HmhzvPysKKrJw3hYmvrd4jasyoioVPdKGQqjyaBMEvTn1HvHWDSVqQ6amyyxRZ5YjpPBBGjJ8yu8S".to_string());
184
185        let res = extract_keys_and_template::<String>("wsh(or_d(multi(2,[b0822927/48'/1'/0'/2']tpubDEvZxV86Br8Knbm9tWcr5Hvmg5cYTYsg92vinqH6Bie6U8ix8CsoN9W11NQygdqVwmHUJpsHXxNsi5gXn36g4xNfLWkMqPuFhRZAmMQ7jjQ/<0;1>/*,[7fc39c07/48'/1'/0'/2']tpubDEvjgXtrUuH3Qtkapny9aE8gN847xiXsf9MDM5XueGf9nrvStqAuBSva3ajGyTvtp8Ti55FvVXsgYSXuS1tQkBeopFuodx2hRUDmQbvKxbZ/<0;1>/*),and_v(v:thresh(2,pkh([b0822927/48'/1'/0'/2']tpubDEvZxV86Br8Knbm9tWcr5Hvmg5cYTYsg92vinqH6Bie6U8ix8CsoN9W11NQygdqVwmHUJpsHXxNsi5gXn36g4xNfLWkMqPuFhRZAmMQ7jjQ/<2;3>/*),a:pkh([7fc39c07/48'/1'/0'/2']tpubDEvjgXtrUuH3Qtkapny9aE8gN847xiXsf9MDM5XueGf9nrvStqAuBSva3ajGyTvtp8Ti55FvVXsgYSXuS1tQkBeopFuodx2hRUDmQbvKxbZ/<2;3>/*),a:pkh([1a1ffd98/48'/1'/0'/2']tpubDFZqzTvGijYb13BC73CkS1er8DrP5YdzMhziN3kWCKUFaW51Yj6ggvf99YpdrkTJy4RT85mxQMHXDiFAKRxzf6BykQgT4pRRBNPshSJJcKo/<0;1>/*)),older(300))))#wp0w3hlw").unwrap();
186        assert_eq!(res.0, "wsh(or_d(multi(2,@0/<0;1>/*,@1/<0;1>/*),and_v(v:thresh(2,pkh(@0/<2;3>/*),a:pkh(@1/<2;3>/*),a:pkh(@2/<0;1>/*)),older(300))))");
187        assert_eq!(res.1.len(), 3);
188        assert_eq!(res.1[0], "[b0822927/48'/1'/0'/2']tpubDEvZxV86Br8Knbm9tWcr5Hvmg5cYTYsg92vinqH6Bie6U8ix8CsoN9W11NQygdqVwmHUJpsHXxNsi5gXn36g4xNfLWkMqPuFhRZAmMQ7jjQ".to_string());
189        assert_eq!(res.1[1], "[7fc39c07/48'/1'/0'/2']tpubDEvjgXtrUuH3Qtkapny9aE8gN847xiXsf9MDM5XueGf9nrvStqAuBSva3ajGyTvtp8Ti55FvVXsgYSXuS1tQkBeopFuodx2hRUDmQbvKxbZ".to_string());
190        assert_eq!(res.1[2], "[1a1ffd98/48'/1'/0'/2']tpubDFZqzTvGijYb13BC73CkS1er8DrP5YdzMhziN3kWCKUFaW51Yj6ggvf99YpdrkTJy4RT85mxQMHXDiFAKRxzf6BykQgT4pRRBNPshSJJcKo".to_string());
191    }
192}
async_hwi/utils.rs

async_hwi/
utils.rs
