Validate a JWS Signature

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.Validate, which validates exactly one signature, identified by a zero-based index, using the key configured at that same index.

require 'chilkat'

success = false

jws = Chilkat::CkJws.new()

#  Load the JWS compact serialization.
jwsCompact = "eyJhbGciOiJIUzI1NiJ9.VGhpcyBpcyB0aGUgY29udGVudCB0byBzaWduLg.<signature>"
success = jws.LoadJws(jwsCompact)
if (success == false)
    print jws.lastErrorText() + "\n";
    exit
end

#  Provide the key for signature 0 (here an HMAC key).
base64Key = "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU="
success = jws.SetMacKey(0,base64Key,"base64")
if (success == false)
    print jws.lastErrorText() + "\n";
    exit
end

#  Validate the signature identified by the zero-based index, using the key configured at that index.
#  Validate returns 1 when the signature or MAC is cryptographically valid, 0 when it is not, or a
#  negative value on error.
v = jws.Validate(0)
if (v < 0)
    print jws.lastErrorText() + "\n";
    exit
end

if (v != 1)
    print "The signature is not valid." + "\n";
    exit
end

print "The signature is valid." + "\n";