just fixed another problem in the code. verify_signature() did not check the digest length!
http://plan9front.googlecode.com/hg-history/8b005ad9d48998e30c4715383c8bc53fae0eccb1/sys/src/libsec/port/x509.c http://code.google.com/p/plan9front/source/detail?r=8b005ad9d48998e30c4715383c8bc53fae0eccb1 -- cinap
