hbc/pywii/pywii-tools/ecchecksig.py

#!/usr/bin/env python2

import sys
import pywii as wii

if len(sys.argv) != 3:
	print "Usage: %s keyfile.[priv|pub] infile"%sys.argv[0]
	sys.exit(1)

if sys.argv[1] == "-":
	k = sys.stdin.read()
else:
	k = open(sys.argv[1],"rb").read()
if len(k) not in (30,60):
	print "Failed to read key"
	sys.exit(2)

if len(k) == 30:
	print "Key is a private key, generating public key..."
	q = wii.ec.priv_to_pub(k)
else:
	q = k

print "Public key:"
pq = q.encode('hex')
print "X =",pq[:30]
print "   ",pq[30:60]
print "Y =",pq[60:90]
print "   ",pq[90:]
print

indata = open(sys.argv[2],"rb").read()

if len(indata) < 64 or indata[:4] != "SIG0":
	print "Invalid header"
	sys.exit(3)

r = indata[4:34]
s = indata[34:64]

sha = wii.SHA.new(indata[64:]).digest()
print "SHA1: %s"%sha.encode('hex')

print
print "Signature:"
print "R =",r[:15].encode('hex')
print "   ",r[15:].encode('hex')
print "S =",s[:15].encode('hex')
print "   ",s[15:].encode('hex')
print

if wii.ec.check_ecdsa(q,r,s,sha):
	print "Signature is VALID"
else:
	print "Signature is INVALID"
	sys.exit(4)