Chilkat2-Python

Validate JWS Using RSASSA-PKCS1-v1_5 SHA-256

See more JSON Web Signatures (JWS) Examples

Validates a JSON Web Signature (JWS) that uses RSASSA-PKCS1-v1_5 SHA-256. Chilkat2-Python

import sys
import chilkat2

success = False

# This requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# This example takes a JSON signature in compact serialization format,
# and uses an RSA public key to validate and recover the protected header and payload.

# We only need a public key for signature validation.  This is the RSA public key
# that is used:

#      {"kty":"RSA", 
#       "n":"ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx
#            HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs
#            D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH
#            SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV
#            MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8
#            NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ", 
#       "e":"AQAB"
#      }

sbPubKey = chilkat2.StringBuilder()
sbPubKey.Append("{\"kty\":\"RSA\",")
sbPubKey.Append("\"n\":\"ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx")
sbPubKey.Append("HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs")
sbPubKey.Append("D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH")
sbPubKey.Append("SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV")
sbPubKey.Append("MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8")
sbPubKey.Append("NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ\",")
sbPubKey.Append("\"e\":\"AQAB\"")
sbPubKey.Append("}")

pubKey = chilkat2.PublicKey()
success = pubKey.LoadFromString(sbPubKey.GetAsString())
if (success == False):
    print(pubKey.LastErrorText)
    sys.exit()

jws = chilkat2.Jws()

# Set the RSA public key:
signatureIndex = 0
jws.SetPublicKey(signatureIndex,pubKey)

# Load the JWS.
sbJws = chilkat2.StringBuilder()
sbJws.Append("eyJhbGciOiJSUzI1NiJ9")
sbJws.Append(".")
sbJws.Append("eyJpc3MiOiJqb2UiLA0KICJleHAiOjEzMDA4MTkzODAsDQogImh0dHA6Ly9leGFt")
sbJws.Append("cGxlLmNvbS9pc19yb290Ijp0cnVlfQ")
sbJws.Append(".")
sbJws.Append("cC4hiUPoj9Eetdgtv3hF80EGrhuB__dzERat0XF9g2VtQgr9PJbu3XOiZj5RZmh7")
sbJws.Append("AAuHIm4Bh-0Qc_lF5YKt_O8W2Fp5jujGbds9uJdbF9CUAr7t1dnZcAcQjbKBYNX4")
sbJws.Append("BAynRFdiuB--f_nZLgrnbyTyWzO75vRK5h6xBArLIARNPvkSjtQBMHlb1L07Qe7K")
sbJws.Append("0GarZRmB_eSN9383LcOLn6_dO--xi12jzDwusC-eOkHWEsqtFZESc6BfI7noOPqv")
sbJws.Append("hJ1phCnvWh6IeYI2w9QOYEUipUTI8np6LbgGY9Fs98rqVt5AXLIhWkWywlVmtVrB")
sbJws.Append("p0igcN_IoypGlUPQGe77Rw")

success = jws.LoadJwsSb(sbJws)
if (success == False):
    print(jws.LastErrorText)
    sys.exit()

# Validate the 1st (and only) signature at index 0..
v = jws.Validate(signatureIndex)
if (v < 0):
    # Perhaps Chilkat was not unlocked or the trial expired..
    print("Method call failed for some other reason.")
    print(jws.LastErrorText)
    sys.exit()

if (v == 0):
    print("Invalid signature.  The RSA key was incorrect, the JWS was invalid, or both.")
    sys.exit()

# If we get here, the signature was validated..
print("Signature validated.")
print("--")

# Recover the original content:
print("Recovered content:")
print(jws.GetPayload("utf-8"))
print("--")

# Examine the protected header:

joseHeader = chilkat2.JsonObject()
success = jws.GetProtectedH(signatureIndex,joseHeader)
if (success == False):
    print(jws.LastErrorText)
    sys.exit()

joseHeader.EmitCompact = False

print("Protected (JOSE) header:")
print(joseHeader.Emit())

# Output:

# 	Signature validated.
# 	--
# 	Recovered content:
# 	{"iss":"joe", 
# 	 "exp":1300819380,
# 	 "http://example.com/is_root":true}
# 	--
# 	Protected (JOSE) header:
# 	{ 
# 	  "alg": "RS256"
# 	}