mirror of
https://github.com/bitcoinbook/bitcoinbook
synced 2024-12-29 09:58:09 +00:00
105 lines
3.7 KiB
Plaintext
105 lines
3.7 KiB
Plaintext
|
--------------------------------------------------
|
|||
|
|
BIP: 13
|
|||
|
|
Title: Address Format for pay-to-script-hash
|
|||
|
|
Author: Gavin Andresen <gavinandresen@gmail.com>
|
|||
|
|
Status: Final
|
|||
|
|
Type: Standards Track
|
|||
|
|
Created: 2011-10-18
|
|||
|
|
--------------------------------------------------
|
|||
|
|
|
|||
|
|
[[abstract]]
|
|||
|
|
Abstract
|
|||
|
|
~~~~~~~~
|
|||
|
|
|
|||
|
|
This BIP describes a new type of Bitcoin address to support arbitrarily
|
|||
|
|
complex transactions. Complexity in this context is defined as what
|
|||
|
|
information is needed by the recipient to respend the received coins, in
|
|||
|
|
contrast to needing a single ECDSA private key as in current
|
|||
|
|
implementations of Bitcoin.
|
|||
|
|
|
|||
|
|
In essence, an address encoded under this proposal represents the
|
|||
|
|
encoded hash of a script, rather than the encoded hash of an ECDSA
|
|||
|
|
public key.
|
|||
|
|
|
|||
|
|
[[motivation]]
|
|||
|
|
Motivation
|
|||
|
|
~~~~~~~~~~
|
|||
|
|
|
|||
|
|
Enable "end-to-end" secure wallets and payments to fund escrow
|
|||
|
|
transactions or other complex transactions. Enable third-party wallet
|
|||
|
|
security services.
|
|||
|
|
|
|||
|
|
[[specification]]
|
|||
|
|
Specification
|
|||
|
|
~~~~~~~~~~~~~
|
|||
|
|
|
|||
|
|
The new bitcoin address type is constructed in the same manner as
|
|||
|
|
existing bitcoin addresses (see link:Base58Check encoding[Base58Check
|
|||
|
|
encoding]):
|
|||
|
|
|
|||
|
|
` base58-encode: [one-byte version][20-byte hash][4-byte checksum]`
|
|||
|
|
|
|||
|
|
Version byte is 5 for a main-network address, 196 for a testnet address.
|
|||
|
|
The 20-byte hash is the hash of the script that will be used to redeem
|
|||
|
|
the coins. And the 4-byte checksum is the first four bytes of the double
|
|||
|
|
SHA256 hash of the version and hash.
|
|||
|
|
|
|||
|
|
[[rationale]]
|
|||
|
|
Rationale
|
|||
|
|
~~~~~~~~~
|
|||
|
|
|
|||
|
|
One criticism is that bitcoin addresses should be deprecated in favor of
|
|||
|
|
a more user-friendly mechanism for payments, and that this will just
|
|||
|
|
encourage continued use of a poorly designed mechanism.
|
|||
|
|
|
|||
|
|
Another criticism is that bitcoin addresses are inherently insecure
|
|||
|
|
because there is no identity information tied to them; if you only have
|
|||
|
|
a bitcoin address, how can you be certain that you're paying who or what
|
|||
|
|
you think you're paying?
|
|||
|
|
|
|||
|
|
Furthermore, truncating SHA256 is not an optimal checksum; there are
|
|||
|
|
much better error-detecting algorithms. If we are introducing a new form
|
|||
|
|
of Bitcoin address, then perhaps a better algorithm should be used.
|
|||
|
|
|
|||
|
|
This is one piece of the simplest path to a more secure bitcoin
|
|||
|
|
infrastructure. It is not intended to solve all of bitcoin's usability
|
|||
|
|
or security issues, but to be an incremental improvement over what
|
|||
|
|
exists today. A future BIP or BIPs should propose more user-friendly
|
|||
|
|
mechanisms for making payments, or for verifying that you're sending a
|
|||
|
|
payment to the Free Software Foundation and not Joe Random Hacker.
|
|||
|
|
|
|||
|
|
Assuming that typing in bitcoin addresses manually will become
|
|||
|
|
increasingly rare in the future, and given that the existing checksum
|
|||
|
|
method for bitcoin addresses seems to work "well enough" in practice and
|
|||
|
|
has already been implemented multiple times, the Author believes no
|
|||
|
|
change to the checksum algorithm is necessary.
|
|||
|
|
|
|||
|
|
The leading version bytes are chosen so that, after base58 encoding, the
|
|||
|
|
leading character is consistent: for the main network, byte 5 becomes
|
|||
|
|
the character '3'. For the testnet, byte 196 is encoded into '2'.
|
|||
|
|
|
|||
|
|
[[backwards-compatibility]]
|
|||
|
|
Backwards Compatibility
|
|||
|
|
~~~~~~~~~~~~~~~~~~~~~~~
|
|||
|
|
|
|||
|
|
This proposal is not backwards compatible, but it fails gracefully-- if
|
|||
|
|
an older implementation is given one of these new bitcoin addresses, it
|
|||
|
|
will report the address as invalid and will refuse to create a
|
|||
|
|
transaction.
|
|||
|
|
|
|||
|
|
[[reference-implementation]]
|
|||
|
|
Reference Implementation
|
|||
|
|
~~~~~~~~~~~~~~~~~~~~~~~~
|
|||
|
|
|
|||
|
|
See base58.cpp1/base58.h at https://github.com/bitcoin/bitcoin/src
|
|||
|
|
|
|||
|
|
[[see-also]]
|
|||
|
|
See Also
|
|||
|
|
~~~~~~~~
|
|||
|
|
|
|||
|
|
* link:bip-0012.mediawiki[BIP 12: OP_EVAL, the original P2SH design]
|
|||
|
|
* link:bip-0016.mediawiki[BIP 16: Pay to Script Hash (aka "/P2SH/")]
|
|||
|
|
* link:bip-0017.mediawiki[BIP 17: OP_CHECKHASHVERIFY, another P2SH
|
|||
|
|
design]
|
|||
|
|
|