Xojo Plugin
Xojo Plugin
Validate JWS with Multiple Signatures using the General JSON Serialization Format
See more JSON Web Signatures (JWS) Examples
Validates and recovers data and headers from a JSON Web Signature (JWS) containing 3 signatures.Note: Chilkat supports all of the following JWS algorithms:
+--------------+-------------------------------+--------------------+ | "alg" Param | Digital Signature or MAC | Implementation | | Value | Algorithm | Requirements | +--------------+-------------------------------+--------------------+ | HS256 | HMAC using SHA-256 | Required | | HS384 | HMAC using SHA-384 | Optional | | HS512 | HMAC using SHA-512 | Optional | | RS256 | RSASSA-PKCS1-v1_5 using | Recommended | | | SHA-256 | | | RS384 | RSASSA-PKCS1-v1_5 using | Optional | | | SHA-384 | | | RS512 | RSASSA-PKCS1-v1_5 using | Optional | | | SHA-512 | | | ES256 | ECDSA using P-256 and SHA-256 | Recommended+ | | ES384 | ECDSA using P-384 and SHA-384 | Optional | | ES512 | ECDSA using P-521 and SHA-512 | Optional | | PS256 | RSASSA-PSS using SHA-256 and | Optional | | | MGF1 with SHA-256 | | | PS384 | RSASSA-PSS using SHA-384 and | Optional | | | MGF1 with SHA-384 | | | PS512 | RSASSA-PSS using SHA-512 and | Optional | | | MGF1 with SHA-512 | | +--------------+-------------------------------+--------------------+
Chilkat Xojo Plugin Downloads
Dim success As Boolean
success = False
// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
// First, prepare the public keys that will be needed for each signature.
// ---------------------------------------------------
// Use the following RSA key loaded from JWK format.
Dim sbRsaJwk As New Chilkat.StringBuilder
success = sbRsaJwk.Append("{""kty"":""RSA"",")
success = sbRsaJwk.Append("""n"":""ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx")
success = sbRsaJwk.Append("HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs")
success = sbRsaJwk.Append("D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH")
success = sbRsaJwk.Append("SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV")
success = sbRsaJwk.Append("MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8")
success = sbRsaJwk.Append("NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ"",")
success = sbRsaJwk.Append("""e"":""AQAB""")
success = sbRsaJwk.Append("}")
Dim rsaKey As New Chilkat.PublicKey
success = rsaKey.LoadFromString(sbRsaJwk.GetAsString())
If (success = False) Then
System.DebugLog(rsaKey.LastErrorText)
Return
End If
// ---------------------------------------------------
// Use the following ECC public key loaded from JWK format.
Dim sbEccJwk As New Chilkat.StringBuilder
success = sbEccJwk.Append("{""kty"":""EC"",")
success = sbEccJwk.Append("""crv"":""P-256"",")
success = sbEccJwk.Append("""x"":""f83OJ3D2xF1Bg8vub9tLe1gHMzV76e8Tus9uPHvRVEU"",")
success = sbEccJwk.Append("""y"":""x_FEzRu9m36HLN_tue659LNpXW6pCyStikYjKIWI5a0""")
success = sbEccJwk.Append("}")
Dim eccKey As New Chilkat.PublicKey
success = eccKey.LoadFromString(sbEccJwk.GetAsString())
If (success = False) Then
System.DebugLog(eccKey.LastErrorText)
Return
End If
// ---------------------------------------------------
// The HMAC key (in base64url format)
Dim hmacKey As String
hmacKey = "AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow"
// The code below will verify each of the signatures in this JWS:
// {
// "payload": "SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu",
// "signatures": [
// {
// "protected": "eyJhbGciOiJSUzI1NiIsImtpZCI6Im15UnNhS2V5In0",
// "signature": "IPMQ02niTQDwLzsRZSCaEm9VEyAX_AVe3HWjniNt9kW-a8d6ZVbd2k6jGae8s1yIh0cgxDnXQ6-p6_sBI0cnMO0xpuJANhh2vFtNJl5lisad94-H3mB3lSfafRqxeYp5D8bh39BPv7y3PrUNVMQdKEJp_D5oJ0ROPTIYx3EG8eJQOx1HO0KqhcUo401XR6KSsIyFm5joBLNKTVzxZUTT1RRZZtwTdeZkbGevugIOX_9gHAtARpV6WaFA4Vvjnq8X9wPgqjWNCQRupadhTPz0JAsa-wy5vXQjsFlXAn43mDPpMfna5Ab3F5pS4yDwkbX6nRn7XBxH1SnnNJRFholQZw"
// },
// {
// "protected": "eyJhbGciOiJFUzI1NiIsImtpZCI6Im15RWNLZXkifQ",
// "signature": "1OQtaT3pgZmkDxvlfghvxL_8kX16WIen6u1MadEq1pA4qytA0--_EwZDNk00GDPWFpoJtKznibMZzLOg_UhHIw"
// },
// {
// "protected": "eyJhbGciOiJIUzI1NiIsImtpZCI6Im15TWFjS2V5In0",
// "signature": "YY8yVjmJJfy7YJOn3uUydG8WCY2PEuCvOLil5Ks5lnw"
// }
// ]
// }
Dim sbJws As New Chilkat.StringBuilder
success = sbJws.Append("{ ")
success = sbJws.Append(" ""payload"": ""SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu"",")
success = sbJws.Append(" ""signatures"": [")
success = sbJws.Append(" { ")
success = sbJws.Append(" ""protected"": ""eyJhbGciOiJSUzI1NiIsImtpZCI6Im15UnNhS2V5In0"",")
success = sbJws.Append(" ""signature"": ""IPMQ02niTQDwLzsRZSCaEm9VEyAX_AVe3HWjniNt9kW-a8d6ZVbd2k6jGae8s1yIh0cgxDnXQ6-p6_sBI0cnMO0xpuJANhh2vFtNJl5lisad94-H3mB3lSfafRqxeYp5D8bh39BPv7y3PrUNVMQdKEJp_D5oJ0ROPTIYx3EG8eJQOx1HO0KqhcUo401XR6KSsIyFm5joBLNKTVzxZUTT1RRZZtwTdeZkbGevugIOX_9gHAtARpV6WaFA4Vvjnq8X9wPgqjWNCQRupadhTPz0JAsa-wy5vXQjsFlXAn43mDPpMfna5Ab3F5pS4yDwkbX6nRn7XBxH1SnnNJRFholQZw""")
success = sbJws.Append(" },")
success = sbJws.Append(" { ")
success = sbJws.Append(" ""protected"": ""eyJhbGciOiJFUzI1NiIsImtpZCI6Im15RWNLZXkifQ"",")
success = sbJws.Append(" ""signature"": ""1OQtaT3pgZmkDxvlfghvxL_8kX16WIen6u1MadEq1pA4qytA0--_EwZDNk00GDPWFpoJtKznibMZzLOg_UhHIw""")
success = sbJws.Append(" },")
success = sbJws.Append(" { ")
success = sbJws.Append(" ""protected"": ""eyJhbGciOiJIUzI1NiIsImtpZCI6Im15TWFjS2V5In0"",")
success = sbJws.Append(" ""signature"": ""YY8yVjmJJfy7YJOn3uUydG8WCY2PEuCvOLil5Ks5lnw""")
success = sbJws.Append(" }")
success = sbJws.Append(" ]")
success = sbJws.Append("}")
Dim jws As New Chilkat.Jws
success = jws.LoadJwsSb(sbJws)
If (success = False) Then
System.DebugLog(jws.LastErrorText)
Return
End If
// The payload is easily accessible:
System.DebugLog("Payload: " + jws.GetPayload("utf-8"))
Dim sbKeyId As New Chilkat.StringBuilder
Dim bCaseSensitive As Boolean
bCaseSensitive = False
Dim protHeader As New Chilkat.JsonObject
Dim numSignatures As Int32
numSignatures = jws.NumSignatures
Dim i As Int32
i = 0
While i < numSignatures
success = jws.GetProtectedH(i,protHeader)
If (success = False) Then
System.DebugLog(jws.LastErrorText)
Return
End If
System.DebugLog("--------------------------")
System.DebugLog(Str(i) + ": ")
// Get the protected header.
protHeader.EmitCompact = False
System.DebugLog(protHeader.Emit())
// Get the key ID ("kid") member.
// Note: In this example, the "kid" values are contained in the protected headers.
// They could've just as easily been located in unprotected headers. In that case,
// we would've called GetUnprotectedH instead of GetProtectedH(i).
sbKeyId.Clear
success = sbKeyId.Append(protHeader.StringOf("kid"))
// Set the key based on key ID.
If (sbKeyId.ContentsEqual("myRsaKey",bCaseSensitive) = True) Then
success = jws.SetPublicKey(i,rsaKey)
End If
If (sbKeyId.ContentsEqual("myEcKey",bCaseSensitive) = True) Then
success = jws.SetPublicKey(i,eccKey)
End If
If (sbKeyId.ContentsEqual("myMacKey",bCaseSensitive) = True) Then
success = jws.SetMacKey(i,hmacKey,"base64url")
End If
// Validate this signature.
Dim v As Int32
v = jws.Validate(i)
If (v < 0) Then
// Perhaps Chilkat was not unlocked or the trial expired..
System.DebugLog("Validate failed for some other reason.")
System.DebugLog(jws.LastErrorText)
Else
If (v = 0) Then
System.DebugLog("Invalid signature. The key was incorrect, the JWS was invalid, or both.")
Else
System.DebugLog("Signature validated.")
End If
End If
i = i + 1
Wend
// The output of this program is:
// Payload: In our village, folks say God crumbles up the old moon into stars.
// --------------------------
// 0:
// {
// "alg": "RS256",
// "kid": "myRsaKey"
// }
//
// Signature validated.
// --------------------------
// 1:
// {
// "alg": "ES256",
// "kid": "myEcKey"
// }
//
// Signature validated.
// --------------------------
// 2:
// {
// "alg": "HS256",
// "kid": "myMacKey"
// }
//
// Signature validated.