Fix #276: remove incorrect keytag+1 heuristic in find_key_in_zone#298
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sage-s11 wants to merge 1 commit intoNLnetLabs:developfrom
Open
Fix #276: remove incorrect keytag+1 heuristic in find_key_in_zone#298sage-s11 wants to merge 1 commit intoNLnetLabs:developfrom
sage-s11 wants to merge 1 commit intoNLnetLabs:developfrom
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…_zone When searching for a key's public RR in the zone, find_key_in_zone() also accepted keys with keytag == pubkey_gen_keytag + 1, based on an old assumption that KSK keytags are always ZSK keytag + 1. This is not guaranteed and causes a bug: if the KSK's keytag happens to equal ZSK keytag + 1, the KSK is incorrectly returned as the ZSK's public key match, and is subsequently excluded from the signed zone as a standalone DNSKEY record, breaking DNSSEC validation. Fix by matching on exact keytag only. The SEP flag (LDNS_KEY_SEP_KEY) is the correct way to distinguish KSK from ZSK, and the caller already handles KSK lookup separately via ldns_key_flags().
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When searching for a key's public RR in the zone, find_key_in_zone() also accepted keys with keytag == pubkey_gen_keytag + 1, based on an old assumption that KSK keytags are always ZSK keytag + 1.
This is not guaranteed and causes a bug: if the KSK's keytag happens to equal ZSK keytag + 1, the KSK is incorrectly returned as the ZSK's public key match, and is subsequently excluded from the signed zone as a standalone DNSKEY record, breaking DNSSEC validation.
Fix by matching on exact keytag only. The SEP flag (LDNS_KEY_SEP_KEY) is the correct way to distinguish KSK from ZSK, and the caller already handles KSK lookup separately via ldns_key_flags().