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Update 06_1_Sending_a_Transaction_to_a_Multisig.md
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# 6.1: Sending a Transaction with a Multisig
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# 6.1: Creating a Multisig from Public Keys
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The first way to vary how you send a basic transaction is to use a multisig. This gives you the ability to require that multiple people (or at least multiple private keys) authorize the use of funds.
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@ -8,197 +8,196 @@ In a typical Bitcoin transaction, bitcoins are sent to an address based on your
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> :book: ***What is a multisignature?*** A multisignature is a methodology that allows more than one person to jointly create a digital signature. It's a general technique for the cryptographic use of keys that goes far beyond Bitcoin.
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Technically, a multisignature cryptographic puzzle is created by Bitcoin using the OP_CHECKMULTISIG command, and typically that's encapsulated in a P2SH address. [§10.4: Scripting a Multisig](10_4_Scripting_a_Multisig.md) will detail how that works more precisely. For now, all you need to know is that you can use `bitcoin-cli` command to create multisignature addresses; funds can be sent to these addresses just like any normal P2PKH or Segwit address, but multiple private keys will be required for the redemption of the funds.
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Technically, a multisignature cryptographic puzzle is created by Bitcoin using the OP_CHECKMULTISIG command, and typically that's encapsulated in a script address. [§10.4: Scripting a Multisig](10_4_Scripting_a_Multisig.md) will detail how that works more precisely. For now, all you need to know is that you can use `bitcoin-cli` command to create multisignature addresses; funds can be sent to these addresses just like any normal address, but multiple private keys will be required for the redemption of the funds.
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As with normal addresses, there are multiple types of multisig addresses that have appeared as Bitcoin has evolved over the years. Currently, there is one deprecated address and three that are in active use. The following shows each, with the flag that you'll be using to create them for the `createmultisig` RPC.
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| Flag | Type | Prefix | Notes |
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| | P2MS | N/A | deprecated |
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| bech32 | P2WSH | bc1q<br>tb1q | |
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| legacy | P2SH | 3<br>2 | default |
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| p2sh-segwit | P2SH-PWPKH | 3<br>2 | |
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Multisigs have been somewhat neglected by Bitcoin Core since the SegWit transition, which is likely why `legacy` addresses are still the default. Nonetheless, just as with regular addresses, you can choose to create multisig addresses from any stage of the SegWit transition: `legacy` for pre-SegWit addresses; `p2sh-segwit` for adddresses used during the transition; and `bech32` for modern SegWit addresses.
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> :book: ***What is a multisignature transaction?*** A multisignature transaction is a Bitcoin transaction that has been sent to a multisignature address, thus requiring the signatures of certain people from the multisignature group to reuse the funds.
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Simple multisignatures require everyone in the group to sign the UTXO when it's spent. However, there's more complexity possible. Multisignatures are generally described as being "m of n". That means that the transaction is locked with a group of "n" keys, but only "m" of them are required to unlock the transaction.
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Simple multisignatures require everyone in the group to sign the UTXO when it's spent. However, there's more complexity possible. Multisignatures are generally described as being "m of n". That means that the transaction is locked with a group of "n" keys, but only "m" of them are required to unlock the transaction, where m≤n.
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> :book: ***What is a m-of-n multisignature?*** In a multisignature, "m" signatures out of a group of "n" are required to form the signature, where "m ≤ n".
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## Create a Multisig Address
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In order to lock a UTXO with multiple private keys, you must first create a multisignature address. The examples used here show the creation (and usage) of a 2-of-2 multisignature.
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In order to lock a UTXO with multiple private keys, you must first create a multisignature address.
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### Create the Addresses
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This requires a number of steps:
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1. Generate "n" addresses.
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2. Record the public key for each address.
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3. Consolidate the public keys onto a single machine.
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4. Create the multisig on one of the machines with the `createmultisig` RPC command.
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5. Record crucial information about the multisig.
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The examples used here show the creation (and usage) of a 2-of-2 multisignature.
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### Generate the Address
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To create a multisignature address, you must first ready the addresses that the multisig will combine. Best practice suggests that you always create new addresses. This means that the participants will each run the `getnewaddress` command on their own machine:
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```
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machine1$ address1=$(bitcoin-cli getnewaddress)
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pubkey1=$(bitcoin-cli -named getaddressinfo address=$address1 | jq -r '.pubkey')
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```
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And:
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```
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machine2$ address2=$(bitcoin-cli getnewaddress)
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pubkey2=$(bitcoin-cli -named getaddressinfo address=$address2 | jq -r '.pubkey')
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```
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Afterwards, one of the recipients (or perhaps some third party) will need to combine the addresses.
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#### Collect Public Keys
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### Record the Public Keys
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However, you can't create a multi-sig with the addresses, as those are the hashes of public keys: you instead need the public keys themselves.
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This information is readily available with the `getaddressinfo` command.
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Over on the remote machine, which we assume here is `machine2`, you can get the information out of the listing.
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This information is readily available with the `getaddressinfo` command, as shown in this example from `machine`.
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```
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machine2$ bitcoin-cli -named getaddressinfo address=$address2
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{
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"address": "tb1qr2tkjh8rs9xn5xaktf5phct0wxqufplawrfd9q",
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"scriptPubKey": "00141a97695ce3814d3a1bb65a681be16f7181c487fd",
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"address": "tb1qf45g34w78hkkf5la8rqhppdcxt248j2y0vw5q5",
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"scriptPubKey": "00144d6888d5de3ded64d3fd38c17085b832d553c944",
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"ismine": true,
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"solvable": true,
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"desc": "wpkh([fe6f2292/0'/0'/1']02bfde48be4aa8f4bf76c570e98a8d287f9be5638412ab38dede8e78df82f33fa3)#zc64l8dw",
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"desc": "wpkh([fb82fc2a/84h/1h/0h/0/1]02dee31254b0f5e38a596492d68781e793c8f88b81ec23cbd806dfc3145fea69fc)#dgx45xul",
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"parent_desc": "wpkh([fb82fc2a/84h/1h/0h]tpubDDANxQDsqt2qiSniMeXoiQ18Z6aGU271czqFqSapYR98wPJosHTkiMc1MrWxF96XR3tjpGhMeB48cJkQJFnQFLRLpduiWFa7EocT3JjUedp/0/*)#lqryzjw5",
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"iswatchonly": false,
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"isscript": false,
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"iswitness": true,
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"witness_version": 0,
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"witness_program": "1a97695ce3814d3a1bb65a681be16f7181c487fd",
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"pubkey": "02bfde48be4aa8f4bf76c570e98a8d287f9be5638412ab38dede8e78df82f33fa3",
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"witness_program": "4d6888d5de3ded64d3fd38c17085b832d553c944",
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"pubkey": "02dee31254b0f5e38a596492d68781e793c8f88b81ec23cbd806dfc3145fea69fc",
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"ischange": false,
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"timestamp": 1592957904,
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"hdkeypath": "m/0'/0'/1'",
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"hdseedid": "1dc70547f2b80e9bb5fde5f34fb3d85f8d8d1dab",
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"hdmasterfingerprint": "fe6f2292",
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"timestamp": 1774547867,
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"hdkeypath": "m/84h/1h/0h/0/1",
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"hdseedid": "0000000000000000000000000000000000000000",
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"hdmasterfingerprint": "fb82fc2a",
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"labels": [
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""
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]
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}
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```
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The `pubkey` address (`02bfde48be4aa8f4bf76c570e98a8d287f9be5638412ab38dede8e78df82f33fa3`) is what's required. Copy it over to your local machine by whatever means you find most efficient and _least error prone_.
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The `pubkey` address (`02dee31254b0f5e38a596492d68781e793c8f88b81ec23cbd806dfc3145fea69fc`) is what's required.
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This process needs to be undertaken for _every_ address from a machine other than the one where the multisig is being built. Obviously, if some third-party is creating the address, then you'll need to do this for every address.
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You can retrieve it from both machines with the following commands:
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> :warning: **WARNING:** Bitcoin's use of public-key hashes as addresses, instead of public keys, actually represents an additional layer of security. Thus, sending a public key slightly increases the vulnerability of the associated address, for some far-future possibility of a compromise of the elliptic curve. You shouldn't worry about having to occasionally send out a public key for a usage such as this, but you should be aware that the public-key hashes represent security, and so the actual public keys should not be sent around willy nilly.
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If one of the addresses was created on your local machine, which we assume here is `machine1`, you can just dump the `pubkey` address into a new variable.
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```
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machine1$ pubkey1=$(bitcoin-cli -named getaddressinfo address=$address1 | jq -r '.pubkey')
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```
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### Create the Address
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And:
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```
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machine2$ pubkey2=$(bitcoin-cli -named getaddressinfo address=$address2 | jq -r '.pubkey')
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```
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### Consolidate the Public Keys
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Via some safe, _accurate_ means, copy the public keys to a single machine.
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> ⚠️ **Public Keys Are Potentially Insecure.** Bitcoin's use of public-key hashes as addresses instead of public keys represents an additional layer of security. Therefore, sending a public key slightly increases the vulnerability of the associated address, for some far-future possibility of a compromise of the elliptic curve. You shouldn't worry about having to occasionally send out a public key for a usage such as this, but you should be aware that the public-key hashes represent security, and so the actual public keys should not be sent around willy nilly.
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### Create the Multisig
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A multisig can now be created with the `createmultisig` command:
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```
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machine1$ bitcoin-cli -named createmultisig nrequired=2 keys='''["'$pubkey1'","02bfde48be4aa8f4bf76c570e98a8d287f9be5638412ab38dede8e78df82f33fa3"]'''
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eithermachine$ bitcoin-cli -named createmultisig nrequired=2 keys='''["'$pubkey1'","'$pubkey2'"]''' address_type=bech32
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{
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"address": "2N8MytPW2ih27LctLjn6LfLFZZb1PFSsqBr",
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"redeemScript": "522102da2f10746e9778dd57bd0276a4f84101c4e0a711f9cfd9f09cde55acbdd2d1912102bfde48be4aa8f4bf76c570e98a8d287f9be5638412ab38dede8e78df82f33fa352ae",
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"descriptor": "sh(multi(2,02da2f10746e9778dd57bd0276a4f84101c4e0a711f9cfd9f09cde55acbdd2d191,02bfde48be4aa8f4bf76c570e98a8d287f9be5638412ab38dede8e78df82f33fa3))#0pazcr4y"
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"address": "tb1qj885390pmsaggamryky7w67ax8xq3dk673epgsyjy7d3gvmvevvqmq6jzy",
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"redeemScript": "5221031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e5268403121023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb252ae",
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"descriptor": "wsh(multi(2,031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e52684031,023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb2))#n3p6hus6"
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}
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```
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When creating the multisignature address, you list how many signatures are required with the `nrequired` argument (that's "m" in a "m-of-n" multisignature), then you list the total set of possible signatures with the `keys` argument (that's "n"). Note that the the `keys` entries likely came from different places. In this case, we included `$pubkey1` from the local machine and `02bfde48be4aa8f4bf76c570e98a8d287f9be5638412ab38dede8e78df82f33fa3` from a remote machine.
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When creating the multisignature address, you list how many signatures are required with the `nrequired` argument (that's "m" in a "m-of-n" multisignature), then you list the total set of possible signatures with the `keys` argument (that's "n"). Note that the the `keys` entries likely came from different places. In this case, we included `$pubkey1` from the local machine and `$pubkey2` that we filled in using the public key from a remote machine.
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> :information_source: **NOTE — M-OF-N VS N-OF-N:** This example shows the creation of a simple 2-of-2 multisig. If you instead want to create an m-of-n signature where "m < n", you adjust the `nrequired` field and/or the number of signatures in the `keys` JSON object. For a 1-of-2 multisig, you'd set `nrequired=1` and also list two keys, while for a 2-of-3 multisig, you'd leave `nrequired=2`, but add one more public key to the `keys` listing.
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> ℹ️ **Note: m-of-n vs. n-of-n.** This example shows the creation of a simple 2-of-2 multisig. If you instead want to create an m-of-n signature where "m < n", you adjust the `nrequired` field and/or the number of signatures in the `keys` JSON object. For a 1-of-2 multisig, you'd set `nrequired=1` and also list two keys, while for a 2-of-3 multisig, you'd leave `nrequired=2`, but add one more public key to the `keys` listing.
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When used correctly, `createmultisig` returns three results, all of which are critically important.
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The _address_ is what you'll give out to people who want to send funds. You'll notice that it has a new prefix of `2`, exactly like those P2SH-SegWit addresses. That's because, like them, `createmultisig` is actually creating a totally new type of address called a P2SH address. It works exactly like a standard P2PKH address for sending funds, but since this one has been built to require multiple addresses, you'll need to do a little more work to spend them.
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* The ***address*** is what you'll give out to people who want to send funds. It will always be a script address instead of a normal public-key-hash address, though for native SegWit address, they all look the same, either `bc1q` or `tb1q`. In any case, as we saw in [§4.6](4_6_Sending_Coins_to_Other_Addresses.md), all the addresses receive coins in the same way, so you don't need to worry about that.
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* The ***redeemScript*** is what you need to redeem the funds (along with the private keys for "m" of the "n" addresses). This script is another special feature of P2SH addresses and will be fully explained in [§10.3: Running a Bitcoin Script with P2SH](10_3_Running_a_Bitcoin_Script_with_P2SH.md). For now, just be aware that it's a bit of data that's required to get your money.
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* The ***descriptor*** is the standardized description for an address that we met in [§3.4: Understanding the Descriptor](03_4_Understanding_the_Descriptor.md). It provides one way that you could import this address back to the other machine, using the `importdescriptors` RPC.
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> :link: **SIGNET vs MAINNET:** On signet (or testnet) the prefix for P2SH addresses is `2`, while on mainnet, it's `3`.
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> 📖 ***What is a script address?*** A script address is a different type of recipient than a standard SegWit address, used for funds whose redemption are based on more complex Bitcoin Scripts. It can be a P2SH, P2WSH, or P2TR address. `bitcoin-cli` uses P2SH encapsulation to help standardize and simplify its multisigs as "P2SH multisigs", just like P2SH-SegWit was using P2SH to standardize its SegWit addresses and make them fully backward compatible.
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The _redeemScript_ is what you need to redeem the funds (along with the private keys for "m" of the "n" addresses). This script is another special feature of P2SH addresses and will be fully explained in [§10.3: Running a Bitcoin Script with P2SH](10_3_Running_a_Bitcoin_Script_with_P2SH.md). For now, just be aware that it's a bit of data that's required to get your money.
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> ⚠️ **Multisig Size Limits.** Classic multisigs have a limit to 20-of-20 multisigs and the classic `redeemScript` could only fit 15 public keys. P2SH and P2WSH multisigs, like the ones described in this chapter can be no bigger than that.
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The _descriptor_ is the standardized description for an address that we met in [§3.5: Understanding the Descriptor](03_5_Understanding_the_Descriptor.md). It provides one way that you could import this address back to the other machine, using the `importmulti` RPC.
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> :book: ***What is a P2SH address?*** P2SH stands for Pay-to-script-hash. It's a different type of recipient than a standard P2PKH address or even a Bech32, used for funds whose redemption are based on more complex Bitcoin Scripts. `bitcoin-cli` uses P2SH encapsulation to help standardize and simplify its multisigs as "P2SH multisigs", just like P2SH-SegWit was using P2SH to standardize its SegWit addresses and make them fully backward compatible.
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> :warning: **WARNING:** P2SH multisig addresses, like the ones created by `bitcoin-cli`, have a limit for "m" and "n" in multisigs based on the maximum size of the redeem script, which is currently 520 bytes. Practically, you won't hit this unless you're doing something excessive.
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### Save Your Work
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### Record Crucial Info
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Here's an important caveat: nothing about your multisig is saved into your wallet using these basic techniques. In order to later redeem money sent to this multisignature address, you're going to need to retain two crucial bits of information:
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* A list of the Bitcoin addresses used in the multisig.
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* A list of the Bitcoin addresses used in the multisig, _in order_.
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* The type of address created.
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* The `redeemScript` output by `createmultsig`.
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Technically, the `redeemScript` can be recreated by rerunning `createmultisig` with the complete list of public keys _in the same order_ and with the right m-of-n count. But, it's better to hold onto it and save yourself stress and grief.
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Technically, the `redeemScript` can be recreated by rerunning `createmultisig` with the complete list of public keys _in the same order_ and with the right m-of-n count and the right address type. But, it's better to hold onto it and save yourself stress and grief.
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### Watch the Order
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### Everything Matters
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All the defails matter, including the order of public keys and the type of address created.
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If you put your keys in a different order, a different address will be created:
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Here's one thing to be very wary of: _order matters_. The order of keys used to create a multi-sig creates a unique hash, which is to say if you put the keys in a different order, they'll produce a different address, as shown:
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```
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$ bitcoin-cli -named createmultisig nrequired=2 keys='''["'$pubkey1'","'$pubkey2'"]'''
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machine1$ bitcoin-cli -named createmultisig nrequired=2 keys='''["'$pubkey1'","'$pubkey2'"]''' address_type=bech32
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{
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"address": "2NFBQvz57UzKWDr2Vx5D667epVZifjGixkm",
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"redeemScript": "52210342b306e410283065ffed38c3139a9bb8805b9f9fa6c16386e7ea96b1ba54da0321039cd6842869c1bfec13cfdbb7d8285bc4c501d413e6633e3ff75d9f13424d99b352ae",
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"descriptor": "sh(multi(2,0342b306e410283065ffed38c3139a9bb8805b9f9fa6c16386e7ea96b1ba54da03,039cd6842869c1bfec13cfdbb7d8285bc4c501d413e6633e3ff75d9f13424d99b3))#8l6hvjsk"
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"address": "tb1qj885390pmsaggamryky7w67ax8xq3dk673epgsyjy7d3gvmvevvqmq6jzy",
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"redeemScript": "5221031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e5268403121023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb252ae",
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"descriptor": "wsh(multi(2,031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e52684031,023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb2))#n3p6hus6"
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}
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standup@btctest20:~$ bitcoin-cli -named createmultisig nrequired=2 keys='''["'$pubkey2'","'$pubkey1'"]'''
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machine2$ bitcoin-cli -named createmultisig nrequired=2 keys='''["'$pubkey2'","'$pubkey1'"]''' address_type=bech32
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{
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"address": "2N5bC4Yc5Pqept1y8nPRqvWmFSejkVeRb1k",
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"redeemScript": "5221039cd6842869c1bfec13cfdbb7d8285bc4c501d413e6633e3ff75d9f13424d99b3210342b306e410283065ffed38c3139a9bb8805b9f9fa6c16386e7ea96b1ba54da0352ae",
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"descriptor": "sh(multi(2,039cd6842869c1bfec13cfdbb7d8285bc4c501d413e6633e3ff75d9f13424d99b3,0342b306e410283065ffed38c3139a9bb8805b9f9fa6c16386e7ea96b1ba54da03))#audl88kg"
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"address": "tb1qu6ch3yccaqjd906xxdxct72qmy75u5z5yky4ql7egpg8qdcy3h2sz09nqy",
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"redeemScript": "5221023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb221031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e5268403152ae",
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"descriptor": "wsh(multi(2,023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb2,031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e52684031))#m3w9ufgy"
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}
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```
|
||||
More notably, each ordering creates a different _redeemScript_. That means that if you used these basic techniques and failed to save the redeemScript as you were instructed, you'll have to walk through an ever-increasing number of variations to find the right one when you try and spend your funds!
|
||||
|
||||
If you choose a different address type, a different address will be created:
|
||||
|
||||
```
|
||||
machine1$ bitcoin-cli -named createmultisig nrequired=2 keys='''["'$pubkey1'","'$pubkey2'"]''' address_type=bech32
|
||||
{
|
||||
"address": "tb1qj885390pmsaggamryky7w67ax8xq3dk673epgsyjy7d3gvmvevvqmq6jzy",
|
||||
"redeemScript": "5221031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e5268403121023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb252ae",
|
||||
"descriptor": "wsh(multi(2,031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e52684031,023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb2))#n3p6hus6"
|
||||
}
|
||||
|
||||
machine1$ bitcoin-cli -named createmultisig nrequired=2 keys='''["'$pubkey1'","'$pubkey2'"]''' address_type=legacy
|
||||
{
|
||||
"address": "2NCt5FkriaYJYsFsg8MvCsbCFNMa5ydiWx5",
|
||||
"redeemScript": "5221031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e5268403121023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb252ae",
|
||||
"descriptor": "sh(multi(2,031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e52684031,023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb2))#x4mvkn9g"
|
||||
}
|
||||
```
|
||||
|
||||
To be precise, each ordering and each address type creates a different _redeemScript_. That means that if you used these basic techniques and failed to save the redeemScript as you were instructed, you'll have to walk through an ever-increasing number of variations to find the right one when you try and spend your funds!
|
||||
|
||||
[BIP67](https://github.com/bitcoin/bips/blob/master/bip-0067.mediawiki) suggests a way to lexicographically order keys, so that they always generate the same multisignatures. ColdCard and Electrum are among the wallets that already support this. Of course, this can cause troubles on its own if you don't know if a multisig address was created with sorted or unsorted keys. Once more, [descriptors](03_5_Understanding_the_Descriptor.md) come to the rescue. If a multisig is unsorted, it's built with the function `multi` and if it's sorted it's built with the function `sortedmulti`.
|
||||
|
||||
If you look at the `desc`riptor for the multisig that you created above, you'll see that Bitcoin Core doesn't currently sort its multisigs:
|
||||
```
|
||||
"descriptor": "sh(multi(2,02da2f10746e9778dd57bd0276a4f84101c4e0a711f9cfd9f09cde55acbdd2d191,02bfde48be4aa8f4bf76c570e98a8d287f9be5638412ab38dede8e78df82f33fa3))#0pazcr4y"
|
||||
"descriptor": "wsh(multi(2,031aac673977274b5e76aad5fb6a420b0e1b7f49f89831388b71bd4a6e52684031,023b27451c83b9d6f8ab4573c5ff9eadf51c5d69bae7dfbbd7c06c21f939489fb2))#n3p6hus6"
|
||||
```
|
||||
However, if it imports an address with type `sortedmulti`, it'll do the right thing, which is the whole point of descriptors!
|
||||
|
||||
## Send to a Multisig Address
|
||||
|
||||
If you've got a multisignature in a convenient P2SH format, like the one generated by `bitcoin-cli`, it can be sent to exactly like a normal address.
|
||||
```
|
||||
$ utxo_txid=$(bitcoin-cli listunspent | jq -r '.[0] | .txid')
|
||||
$ utxo_vout=$(bitcoin-cli listunspent | jq -r '.[0] | .vout')
|
||||
$ recipient="2N8MytPW2ih27LctLjn6LfLFZZb1PFSsqBr"
|
||||
|
||||
$ rawtxhex=$(bitcoin-cli -named createrawtransaction inputs='''[ { "txid": "'$utxo_txid'", "vout": '$utxo_vout' } ]''' outputs='''{ "'$recipient'": 0.000065}''')
|
||||
$ bitcoin-cli -named decoderawtransaction hexstring=$rawtxhex
|
||||
{
|
||||
"txid": "b164388854f9701051809eed166d9f6cedba92327e4296bf8a265a5da94f6521",
|
||||
"hash": "b164388854f9701051809eed166d9f6cedba92327e4296bf8a265a5da94f6521",
|
||||
"version": 2,
|
||||
"size": 83,
|
||||
"vsize": 83,
|
||||
"weight": 332,
|
||||
"locktime": 0,
|
||||
"vin": [
|
||||
{
|
||||
"txid": "c6de60427b28d8ec8102e49771e5d0348fc3ef6a5bf02eb864ec745105a6951b",
|
||||
"vout": 0,
|
||||
"scriptSig": {
|
||||
"asm": "",
|
||||
"hex": ""
|
||||
},
|
||||
"sequence": 4294967295
|
||||
}
|
||||
],
|
||||
"vout": [
|
||||
{
|
||||
"value": 0.00006500,
|
||||
"n": 0,
|
||||
"scriptPubKey": {
|
||||
"asm": "OP_HASH160 a5d106eb8ee51b23cf60d8bd98bc285695f233f3 OP_EQUAL",
|
||||
"hex": "a914a5d106eb8ee51b23cf60d8bd98bc285695f233f387",
|
||||
"reqSigs": 1,
|
||||
"type": "scripthash",
|
||||
"addresses": [
|
||||
"2N8MytPW2ih27LctLjn6LfLFZZb1PFSsqBr"
|
||||
]
|
||||
}
|
||||
}
|
||||
]
|
||||
}
|
||||
|
||||
$ signedtx=$(bitcoin-cli -named signrawtransactionwithwallet hexstring=$rawtxhex | jq -r '.hex')
|
||||
$ bitcoin-cli -named sendrawtransaction hexstring=$signedtx
|
||||
b164388854f9701051809eed166d9f6cedba92327e4296bf8a265a5da94f6521
|
||||
```
|
||||
As you can see, there was nothing unusual in the creation of the transaction, and it looked entirely normal, albeit with an address with a different prefix than normal (`2N8MytPW2ih27LctLjn6LfLFZZb1PFSsqBr`). No surprise, as we similarly saw no difference when we sent to Bech32 addresses for the first time in [§4.6](04_6_Creating_a_Segwit_Transaction.md).
|
||||
Once you've got a multisig, you can send to it normally, either creating a transaction yourself from the command line or tapping a faucet. [§4.6](04_6_Sending_Coins_to_Other_Addresses.md) included a demonstration of sending to a P2SH address, and that's one of the types that is used to create multisig addresses.
|
||||
|
||||
## Summary: Sending a Transaction with a Multisig
|
||||
|
||||
Multisig addresses lock funds to multiple private keys — possibly requiring all of those private keys for redemption, and possibly requiring just some from the set. They're easy enough to create with `bitcoin-cli` and they're entirely normal to send to. This ease is due in large part to the invisible use of P2SH (pay-to-script-hash) addresses, a large topic that we've touched upon twice now, with P2SH-SegWit and multisig addresses, and one that will get more coverage in the future.
|
||||
Multisig addresses lock funds to multiple private keys — possibly requiring all of those private keys for redemption, and possibly requiring just some from the set. They're easy enough to create with `bitcoin-cli` and they're entirely normal to send to. This ease is due in large part to the invisible use of P2SH (pay-to-script-hash) or P2WSH (pay-to-witness-script-hash) addresses, a large topic that wwill get more coverage in the future.
|
||||
|
||||
> :fire: ***What is the power of multisignatures?*** Multisignatures allow the modeling of a variety of financial arrangements such as corporations, partnerships, committees, and other groups. A 1-of-2 multisig might be a married couple's joint bank account, while a 2-of-2 multisig might be used for large expenditures by a Limited Liability Partnership. Multisignatures also form one of the bases of Smart Contracts. For example, a real estate deal could be closed with a 2-of-3 multisig, where the signatures are submitted by the buyer, the seller, and a licensed escrow agent. Once the escrow agent agrees that all of the conditions have been met, he frees up the funds for the seller; or alternatively, the buyer and seller can jointly free the funds.
|
||||
> 🔥 ***What is the power of multisignatures?*** Multisignatures allow the modeling of a variety of financial arrangements such as corporations, partnerships, committees, and other groups. A 1-of-2 multisig might be a married couple's joint bank account, while a 2-of-2 multisig might be used for large expenditures by a Limited Liability Partnership. Multisignatures also form one of the bases of Smart Contracts. For example, a real estate deal could be closed with a 2-of-3 multisig, where the signatures are submitted by the buyer, the seller, and a licensed escrow agent. Once the escrow agent agrees that all of the conditions have been met, he frees up the funds for the seller; or alternatively, the buyer and seller can jointly free the funds.
|
||||
|
||||
## What's Next?
|
||||
|
||||
Continue "Expanding Bitcoin Transactions" with [§6.2: Spending a Transaction with a Multisig](06_2_Spending_a_Transaction_to_a_Multisig.md).
|
||||
Continue "Expanding Bitcoin Transactions" with [§6.2: Creating a Multisig from Descriptors](06_2_Spending_a_Transaction_to_a_Multisig.md).
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user