commit fa940c0d9e30d52b168d0ee64bec08c0a88f4edb Author: Nick Mathewson nickm@torproject.org Date: Thu Feb 17 16:16:15 2022 -0500

Be explicit about EXT_FIELD_LEN=0 --- proposals/332-ntor-v3-with-extra-data.md | 2 ++ rend-spec-v3.txt | 1 + 2 files changed, 3 insertions(+)

diff --git a/proposals/332-ntor-v3-with-extra-data.md b/proposals/332-ntor-v3-with-extra-data.md index 8e6dedc..25ae0ba 100644 --- a/proposals/332-ntor-v3-with-extra-data.md +++ b/proposals/332-ntor-v3-with-extra-data.md @@ -343,6 +343,8 @@ server messages. EXT_FIELD_LEN [one byte] EXT_FIELD [EXT_FIELD_LEN bytes]

+(`EXT_FIELD_LEN` may be zero, in which case EXT_FIELD is absent.) + All parties MUST reject messages that are not well-formed per the rules above.

diff --git a/rend-spec-v3.txt b/rend-spec-v3.txt index 1a0b945..fac1395 100644 --- a/rend-spec-v3.txt +++ b/rend-spec-v3.txt @@ -1550,6 +1550,7 @@ Table of contents: The EXT_FIELD_TYPE, EXT_FIELD_LEN, EXT_FIELD entries are reserved for extensions to the introduction protocol. Extensions with unrecognized EXT_FIELD_TYPE values must be ignored. + (`EXT_FIELD_LEN` may be zero, in which case EXT_FIELD is absent.)

Unless otherwise specified in the documentation for an extension type: * Each extension type SHOULD be sent only once in a message.