BOLT 12: add test vector for invalid bech32 padding#1312
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BOLT 12: add test vector for invalid bech32 padding#1312erickcestari wants to merge 1 commit intolightning:masterfrom
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See lightning/bolts#1312 for more details.
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See lightning/bolts#1312 for more details.
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Add validation for bech32 padding in BOLT 12 offer parsing per BIP-173 which states: "Any incomplete group at the end MUST be 4 bits or less, MUST be all zeroes, and is discarded." This adds a test vector from the BOLT specification that ensures offers with invalid padding (exceeding the 4-bit limit) are properly rejected. Previously, LDK would accept offers with invalid bech32 padding. This was identified through differential fuzzing across Lightning implementations (see lightning/bolts#1312). The fix calls `validate_segwit_padding()` from the bech32 crate during offer parsing, and introduces a new `InvalidPadding` variant to `Bolt12ParseError` to surface these errors.
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Add validation for bech32 padding in BOLT 12 offer parsing per BIP-173 which states: "Any incomplete group at the end MUST be 4 bits or less, MUST be all zeroes, and is discarded." This adds a test vector from the BOLT specification that ensures offers with invalid padding (exceeding the 4-bit limit) are properly rejected. Previously, LDK would accept offers with invalid bech32 padding. This was identified through differential fuzzing across Lightning implementations (see lightning/bolts#1312). The fix calls `validate_segwit_padding()` from the bech32 crate during offer parsing, and introduces a new `InvalidPadding` variant to `Bolt12ParseError` to surface these errors.
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Add validation for bech32 padding in BOLT 12 offer parsing per BIP-173 which states: "Any incomplete group at the end MUST be 4 bits or less, MUST be all zeroes, and is discarded." This adds a test vector from the BOLT specification that ensures offers with invalid padding (exceeding the 4-bit limit) are properly rejected. Previously, LDK would accept offers with invalid bech32 padding. This was identified through differential fuzzing across Lightning implementations (see lightning/bolts#1312). The fix calls `validate_segwit_padding()` from the bech32 crate during offer parsing, and introduces a new `InvalidPadding` variant to `Bolt12ParseError` to surface these errors. Signed-off-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
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ACK d5d1e65
I reproduce and provide a fix in LDK lightningdevkit/rust-lightning#4349
Differential fuzzing across Lightning implementations revealed inconsistent handling of bech32 padding. Some implementations (Lightning-kmp, Eclair) enforce BIP-173's 4-bit padding constraint while others (CLN, LDK) do not. Add test vector to clarify that offers with invalid padding must be rejected per BIP-173 rules.
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Closes #1281
Differential fuzzing across Lightning implementations revealed inconsistent handling of bech32 padding. Some implementations (Lightning-kmp, Eclair) enforce BIP-173's 4-bit padding constraint while others (CLN, LDK) do not.
Add test vector to clarify that offers with invalid padding must be rejected per BIP-173 rules.