From eb494125624eb3d311c6b2e45ce403c61faddd62 Mon Sep 17 00:00:00 2001 From: Russell Yanofsky Date: Thu, 6 Sep 2018 09:59:42 -0400 Subject: [PATCH] doc/descriptors.md tweaks Add some implementation details, and tweak phrasing in examples section to be more explicit about how script expressions are used for matching. --- doc/descriptors.md | 42 +++++++++++++++++++++++++----------------- 1 file changed, 25 insertions(+), 17 deletions(-) diff --git a/doc/descriptors.md b/doc/descriptors.md index c23ac06e8..d97e838d7 100644 --- a/doc/descriptors.md +++ b/doc/descriptors.md @@ -22,19 +22,19 @@ Output descriptors currently support: ## Examples -- `pk(0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)` represents a P2PK output. -- `pkh(02c6047f9441ed7d6d3045406e95c07cd85c778e4b8cef3ca7abac09b95c709ee5)` represents a P2PKH output. -- `wpkh(02f9308a019258c31049344f85f89d5229b531c845836f99b08601f113bce036f9)` represents a P2WPKH output. -- `sh(wpkh(03fff97bd5755eeea420453a14355235d382f6472f8568a18b2f057a1460297556))` represents a P2SH-P2WPKH output. -- `combo(0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)` represents a P2PK, P2PKH, P2WPKH, and P2SH-P2WPKH output. -- `sh(wsh(pkh(02e493dbf1c10d80f3581e4904930b1404cc6c13900ee0758474fa94abe8c4cd13)))` represents a (overly complicated) P2SH-P2WSH-P2PKH output. -- `multi(1,022f8bde4d1a07209355b4a7250a5c5128e88b84bddc619ab7cba8d569b240efe4,025cbdf0646e5db4eaa398f365f2ea7a0e3d419b7e0330e39ce92bddedcac4f9bc)` represents a bare *1-of-2* multisig. -- `sh(multi(2,022f01e5e15cca351daff3843fb70f3c2f0a1bdd05e5af888a67784ef3e10a2a01,03acd484e2f0c7f65309ad178a9f559abde09796974c57e714c35f110dfc27ccbe))` represents a P2SH *2-of-2* multisig. -- `wsh(multi(2,03a0434d9e47f3c86235477c7b1ae6ae5d3442d49b1943c2b752a68e2a47e247c7,03774ae7f858a9411e5ef4246b70c65aac5649980be5c17891bbec17895da008cb,03d01115d548e7561b15c38f004d734633687cf4419620095bc5b0f47070afe85a))` represents a P2WSH *2-of-3* multisig. -- `sh(wsh(multi(1,03f28773c2d975288bc7d1d205c3748651b075fbc6610e58cddeeddf8f19405aa8,03499fdf9e895e719cfd64e67f07d38e3226aa7b63678949e6e49b241a60e823e4,02d7924d4f7d43ea965a465ae3095ff41131e5946f3c85f79e44adbcf8e27e080e)))` represents a P2SH-P2WSH *1-of-3* multisig. -- `pk(xpub661MyMwAqRbcFtXgS5sYJABqqG9YLmC4Q1Rdap9gSE8NqtwybGhePY2gZ29ESFjqJoCu1Rupje8YtGqsefD265TMg7usUDFdp6W1EGMcet8)` refers to a single P2PK output, using the public key part from the specified xpub. -- `pkh(xpub68Gmy5EdvgibQVfPdqkBBCHxA5htiqg55crXYuXoQRKfDBFA1WEjWgP6LHhwBZeNK1VTsfTFUHCdrfp1bgwQ9xv5ski8PX9rL2dZXvgGDnw/1'/2)` refers to a single P2PKH output, using child key *1'/2* of the specified xpub. -- `wsh(multi(1,xpub661MyMwAqRbcFW31YEwpkMuc5THy2PSt5bDMsktWQcFF8syAmRUapSCGu8ED9W6oDMSgv6Zz8idoc4a6mr8BDzTJY47LJhkJ8UB7WEGuduB/1/0/*,xpub69H7F5d8KSRgmmdJg2KhpAK8SR3DjMwAdkxj3ZuxV27CprR9LgpeyGmXUbC6wb7ERfvrnKZjXoUmmDznezpbZb7ap6r1D3tgFxHmwMkQTPH/1/0/*))` refers to a chain of *1-of-2* P2WSH multisig outputs, using public keys taken from two HD chains with corresponding derivation paths. +- `pk(0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)` matches a P2PK output with the specified public key. +- `pkh(02c6047f9441ed7d6d3045406e95c07cd85c778e4b8cef3ca7abac09b95c709ee5)` matches a P2PKH output with the specified public key. +- `wpkh(02f9308a019258c31049344f85f89d5229b531c845836f99b08601f113bce036f9)` matches a P2WPKH output with the specified public key. +- `sh(wpkh(03fff97bd5755eeea420453a14355235d382f6472f8568a18b2f057a1460297556))` matches a P2SH-P2WPKH output with the specified public key. +- `combo(0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)` matches any P2PK, P2PKH, P2WPKH, or P2SH-P2WPKH output with the specified public key. +- `sh(wsh(pkh(02e493dbf1c10d80f3581e4904930b1404cc6c13900ee0758474fa94abe8c4cd13)))` matches an (overly complicated) P2SH-P2WSH-P2PKH output with the specified public key. +- `multi(1,022f8bde4d1a07209355b4a7250a5c5128e88b84bddc619ab7cba8d569b240efe4,025cbdf0646e5db4eaa398f365f2ea7a0e3d419b7e0330e39ce92bddedcac4f9bc)` matches a bare *1-of-2* multisig output with keys in the specified order. +- `sh(multi(2,022f01e5e15cca351daff3843fb70f3c2f0a1bdd05e5af888a67784ef3e10a2a01,03acd484e2f0c7f65309ad178a9f559abde09796974c57e714c35f110dfc27ccbe))` matches a P2SH *2-of-2* multisig output with keys in the specified order. +- `wsh(multi(2,03a0434d9e47f3c86235477c7b1ae6ae5d3442d49b1943c2b752a68e2a47e247c7,03774ae7f858a9411e5ef4246b70c65aac5649980be5c17891bbec17895da008cb,03d01115d548e7561b15c38f004d734633687cf4419620095bc5b0f47070afe85a))` matches a P2WSH *2-of-3* multisig output with keys in the specified order. +- `sh(wsh(multi(1,03f28773c2d975288bc7d1d205c3748651b075fbc6610e58cddeeddf8f19405aa8,03499fdf9e895e719cfd64e67f07d38e3226aa7b63678949e6e49b241a60e823e4,02d7924d4f7d43ea965a465ae3095ff41131e5946f3c85f79e44adbcf8e27e080e)))` matches a P2SH-P2WSH *1-of-3* multisig output with keys in the specified order. +- `pk(xpub661MyMwAqRbcFtXgS5sYJABqqG9YLmC4Q1Rdap9gSE8NqtwybGhePY2gZ29ESFjqJoCu1Rupje8YtGqsefD265TMg7usUDFdp6W1EGMcet8)` matches a P2PK output with the public key of the specified xpub. +- `pkh(xpub68Gmy5EdvgibQVfPdqkBBCHxA5htiqg55crXYuXoQRKfDBFA1WEjWgP6LHhwBZeNK1VTsfTFUHCdrfp1bgwQ9xv5ski8PX9rL2dZXvgGDnw/1'/2)` matches a P2PKH output with child key *1'/2* of the specified xpub. +- `wsh(multi(1,xpub661MyMwAqRbcFW31YEwpkMuc5THy2PSt5bDMsktWQcFF8syAmRUapSCGu8ED9W6oDMSgv6Zz8idoc4a6mr8BDzTJY47LJhkJ8UB7WEGuduB/1/0/*,xpub69H7F5d8KSRgmmdJg2KhpAK8SR3DjMwAdkxj3ZuxV27CprR9LgpeyGmXUbC6wb7ERfvrnKZjXoUmmDznezpbZb7ap6r1D3tgFxHmwMkQTPH/0/0/*))` matches any *1-of-2* P2WSH multisig output where the first multisig key is the *1/0/`i`* child of the first specified xpub and the second multisig key is the *0/0/`i`* child of the second specified xpub, and `i` is any number in a configurable range (`0-1000` by default). ## Reference @@ -91,6 +91,14 @@ on Bitcoin's OP_CHECKMULTISIG opcode. To support these, we introduce the multisig policy, where any *k* out of the *n* provided public keys must sign. +Key order is significant. A `multi()` expression will only match multisig +scripts with keys in the specified order. Also, to prevent a combinatorial +explosion of the search space, if more than one `multi()` key arguments is a +BIP32 wildcard path ending in `/*` or `*'`, the `multi()` expression only +matches multisig scripts with the `i`th child key from each wildcard path in +lockstep, rather than scripts with any combination of child keys from each +wildcard path. + ### BIP32 derived keys and chains Most modern wallet software and hardware uses keys that are derived using @@ -101,7 +109,7 @@ path consists of a sequence of 0 or more integers (in the range *0..231-1*) each optionally followed by `'` or `h`, and separated by `/` characters. The string may optionally end with the literal `/*` or `/*'` (or `/*h`) to refer to all unhardened or hardened -child keys instead. +child keys in a configurable range (by default `0-1000`, inclusive). Whenever a public key is described using a hardened derivation step, the script cannot be computed without access to the corresponding private @@ -119,6 +127,6 @@ steps, or for dumping wallet descriptors including private key material. In order to easily represent the sets of scripts currently supported by existing Bitcoin Core wallets, a convenience function `combo` is -provided, which takes as input a public key, and constructs the P2PK, -P2PKH, P2WPKH, and P2SH-P2WPH scripts for that key. In case the key is -uncompressed, it only constructs P2PK and P2PKH. +provided, which takes as input a public key, and matches P2PK, +P2PKH, P2WPKH, or P2SH-P2WPH scripts for that key. In case the key is +uncompressed, it only matches the P2PK or P2PKH scripts. \ No newline at end of file