Merge branch 'hspow' into 'main'

hspow: Clarifications to scheme and descriptor Item

See merge request tpo/core/torspec!254

1 files changed, 10 insertions, 6 deletions

diff --git a/spec/rend-spec/introduction-protocol.md b/spec/rend-spec/introduction-protocol.md
index 02ed828..829ba98 100644
--- a/spec/rend-spec/introduction-protocol.md
+++ b/spec/rend-spec/introduction-protocol.md
@@ -505,7 +505,7 @@ EXT_FIELD_TYPE:
 ```text
 The EXT_FIELD content format is:
 
-    POW_VERSION    [1 byte]
+    POW_SCHEME     [1 byte]
     POW_NONCE      [16 bytes]
     POW_EFFORT     [4 bytes]
     POW_SEED       [4 bytes]
@@ -513,7 +513,7 @@ The EXT_FIELD content format is:
 
 where:
 
-POW_VERSION is 1 for the protocol specified here
+POW_SCHEME is 1 for the `v1` protocol specified here
 POW_NONCE is the nonce value chosen by the client's solver
 POW_EFFORT is the effort value chosen by the client,
            as a 32-bit integer in network byte order
@@ -521,10 +521,14 @@ POW_SEED identifies which seed was in use, by its first 4 bytes
 POW_SOLUTION is a matching proof computed by the client's solver
 ```
 
-Only version 1 is currently defined.
-Other versions may have a different format.
-A correctly functioning client only submits solutions with a version and seed which were advertised by the server and have not yet expired.
-An extension with an unknown version or expired seed is suspicious and SHOULD result in introduction failure.
+Only SCHEME 1, `v1`, is currently defined.
+Other schemes may have a different format,
+after the POW_SCHEME byte.
+A correctly functioning client only submits solutions with a scheme and seed which were advertised by the server
+(using a "pow-params" Item in the
+[HS descriptor](hsdesc-encrypt.md#second-layer-plaintext))
+and have not yet expired.
+An extension with an unknown scheme or expired seed is suspicious and SHOULD result in introduction failure.
 
 Introduced in tor-0.4.8.1-alpha.