zec
/
zips
mirror of https://github.com/zcash/zips.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Correct the encoding of a_sk,par for Sprout child derivation. 

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
This commit is contained in:
Daira Hopwood 2018-07-13 03:22:32 +01:00
parent 777d82a26f
commit 3018efc0f3
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
zip-0032.rst
View File

@ -273,7 +273,9 @@ CDKsk((*a*\ :sub:`sk,par`\ , *c*\ :sub:`par`\ ), *i*) → (*a*\ :sub:`sk,i`\ , *
- Check whether *i* ≥ 2\ :sup:`31` (whether the child is a hardened key).
- If so (hardened child): let *I* = PRF\ :sup:`expand`\ (*c*\ :sub:`par`\ , [0x80] || *a*\ :sub:`sk,par` || I2LEOSP\ :sub:`32`\ (*i*))
- If so (hardened child): let *I* = PRF\ :sup:`expand`\ (*c*\ :sub:`par`\ , [0x80] || *ASK*\ :sub:`par` || I2LEOSP\ :sub:`32`\ (*i*))
where *ASK*\ :sub:`par` is the encoding of *a*\ :sub:`sk,par` excluding lead bytes from
[#sapling-spec]_ section 5.6.8.
- If not (normal child): return failure
- Split *I* into two 32-byte sequences, *I*\ :sub:`L` and *I*\ :sub:`R`\ .