clean up I2OSP - Githubissues

mozilla-services / go-cose

go library for CBOR Object Signing and Encryption (COSE)

Mozilla Public License 2.0

40 stars 18 forks source link

clean up I2OSP #41

Closed g-k closed 6 years ago

g-k commented 6 years ago

Changes:

use constant time copy
check for errors

Running the single timing test with repeated go test -run TestI2OSPTiming gets worse from ~1000 ns on master to 2000-3000ns on this branch

However, go test -run TestI2OSP (which calls the correctness then the timing test) goes from ~500 ns on master to under ~200ns on this branch

Not sure if this fixes #40 or not.

Need to profile this, but we could:

iterate through by byte instead
try to make the error checking constant time
find out if the big.Int.Bytes() call is accounting for the discrepancy

r? @franziskuskiefer

coveralls commented 6 years ago

Coverage increased (+0.8%) to 97.164% when pulling 55494f43b198c732da64fec064ab052324e42d2c on fix-i2osp into 3d08d63c9c1da50b3b4bf263e34acc36388a02e8 on master.