(CkPython) Verify JWT Using an RSA Public Key (RS256, RS384, RS512)

Demonstrates how to verify a JWT that was signed using an RSA private key.

This example verifies the RSA signature. It also does the following:

• Checks to see if the time constraints ("nbf" and "exp") are valid.
• Recovers the original JOSE header.
• Recovers the original claims JSON.

Chilkat Python Downloads install with pip pip3 install chilkat or download... Python Module for Windows, MacOS, Linux, Alpine Linux, Solaris

import chilkat

# Demonstrates how to verify an JWT using an RSA public key.

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

pubKey = chilkat.CkPublicKey()
success = pubKey.LoadFromFile("qa_data/pem/rsa_public.pem")

jwt = chilkat.CkJwt()

token = "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJodHRwOi8vZXhhbXBsZS5vcmciLCJzdWIiOiJKb2huIiwiYXVkIjoiaHR0cDovL2V4YW1wbGUuY29tIiwiaWF0IjoxNDYzNDQ1MjM4LCJuYmYiOjE0NjM0NDUyMzgsImV4cCI6MTQ2MzQ0ODgzOH0.XRtqed6nuJ9lrp0wbNdDX3fCkSh_d9cHAniPbNcqm7G-5N3mtI5ntQvZBDP3pHtECVqufuDwW7XgUtzAi0ZXhyiRm1iZ3wMSN5lHWv52OQJmMHPA7VPd8Q1hDG-tx-QswzJKd75OEUHP7wIXq2Mg_YVElfDvJI6TGjGyS1y-RLHlz-ldlGsEwIBkO0PtzIYTVov97x8p9KCsPNhS4lZUIqKOYoTZUV5LpuAWARl-636DfMEB_A5_IEaw_W8leh2suP2ULVZxwE-Tk1kBC9tsSGrBrPTtg7sziaV4Lbb0JRANmh98uTRu5f8ji9CVOnpbMiAzjsJSy56kz_olweXSuA"

# First verify the signature.
sigVerified = jwt.VerifyJwtPk(token,pubKey)
print("verified: " + str(sigVerified))

# Let's see if the time constraints, if any, are valid.
# The above JWT was created on the afternoon of 16-May-2016, with an expiration of 1 hour.
# If the current system time is before the "nbf" time, or after the "exp" time,
# then IsTimeValid will return false/0.
# Also, we'll allow a leeway of 60 seconds to account for any clock skew.
# Note: If the token has no "nbf" or "exp" claim fields, then IsTimeValid is always true.
leeway = 60
bTimeValid = jwt.IsTimeValid(token,leeway)
print("time constraints valid: " + str(bTimeValid))

# Now let's recover the original claims JSON (the payload).
payload = jwt.getPayload(token)
# The payload will likely be in compact form:
print(payload)

# We can format for human viewing by loading it into Chilkat's JSON object
# and emit.
json = chilkat.CkJsonObject()
success = json.Load(payload)
json.put_EmitCompact(False)
print(json.emit())

# We can recover the original JOSE header in the same way:
joseHeader = jwt.getHeader(token)
# The payload will likely be in compact form:
print(joseHeader)

# We can format for human viewing by loading it into Chilkat's JSON object
# and emit.
success = json.Load(joseHeader)
json.put_EmitCompact(False)
print(json.emit())