aljaz/lightning
1
0
Fork 0
mirror of https://github.com/aljazceru/lightning.git synced 2025-12-23 17:14:22 +01:00
Code Issues Packages Projects Releases Wiki Activity

script: add check for 32-byte preimage.

Browse Source 
We need to enforce this onchain as we do in the protocol off-chain,
otherwise we can have an onchain redemption we can't redeem upstream
via the protocol.  While Laolu points out there's a 520 byte limit on
witness stack element, that can still make for a larger tx and make
problems for the steal tx case.

The downside is that even the timeout transaction, which used to spend
the HTLC with an empty 'secret', now needs a 32-byte secret, making it
a little larger.  We create a 'bitcoin_witness_htlc' helper for this
case.

See: http://lists.linuxfoundation.org/pipermail/lightning-dev/2016-May/000529.html

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell
2016-05-03 11:24:56 +09:30
parent 02593059cd
commit 1245ffaae3
2 changed files with 31 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
bitcoin/script.h
View File

@@ -87,6 +87,12 @@ u8 **bitcoin_witness_secret(const tal_t *ctx,
const struct bitcoin_signature *sig,
const u8 *witnessscript);
/* Create a witness which spends bitcoin_redeeem_htlc_recv/send */
u8 **bitcoin_witness_htlc(const tal_t *ctx,
const struct sha256 *htlc_or_revocation_preimage,
const struct bitcoin_signature *sig,
const u8 *witnessscript);
/* Is this a pay to script hash? */
bool is_p2sh(const u8 *script, size_t script_len);