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PureBasic

JWS Using RSASSA-PSS using SHA-256 and MGF1 with SHA-256

See more JSON Web Signatures (JWS) Examples

Creates and validates a JSON Web Signature (JWS) using RSASSA-PSS using SHA-256 and MGF1 with SHA-256.

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 PureBasic Downloads

PureBasic
IncludeFile "CkJws.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkPrivateKey.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkPublicKey.pb"

Procedure ChilkatExample()

    success.i = 0

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

    ; Note: This example requires Chilkat v9.5.0.66 or greater.

    ; Use the following RSA key loaded from JWK format.
    sbJwk.i = CkStringBuilder::ckCreate()
    If sbJwk.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkStringBuilder::ckAppend(sbJwk,"{" + Chr(34) + "kty" + Chr(34) + ":" + Chr(34) + "RSA" + Chr(34) + ",")
    CkStringBuilder::ckAppend(sbJwk,Chr(34) + "n" + Chr(34) + ":" + Chr(34) + "ofgWCuLjybRlzo0tZWJjNiuSfb4p4fAkd_wWJcyQoTbji9k0l8W26mPddx")
    CkStringBuilder::ckAppend(sbJwk,"HmfHQp-Vaw-4qPCJrcS2mJPMEzP1Pt0Bm4d4QlL-yRT-SFd2lZS-pCgNMs")
    CkStringBuilder::ckAppend(sbJwk,"D1W_YpRPEwOWvG6b32690r2jZ47soMZo9wGzjb_7OMg0LOL-bSf63kpaSH")
    CkStringBuilder::ckAppend(sbJwk,"SXndS5z5rexMdbBYUsLA9e-KXBdQOS-UTo7WTBEMa2R2CapHg665xsmtdV")
    CkStringBuilder::ckAppend(sbJwk,"MTBQY4uDZlxvb3qCo5ZwKh9kG4LT6_I5IhlJH7aGhyxXFvUK-DWNmoudF8")
    CkStringBuilder::ckAppend(sbJwk,"NAco9_h9iaGNj8q2ethFkMLs91kzk2PAcDTW9gb54h4FRWyuXpoQ" + Chr(34) + ",")
    CkStringBuilder::ckAppend(sbJwk,Chr(34) + "e" + Chr(34) + ":" + Chr(34) + "AQAB" + Chr(34) + ",")
    CkStringBuilder::ckAppend(sbJwk,Chr(34) + "d" + Chr(34) + ":" + Chr(34) + "Eq5xpGnNCivDflJsRQBXHx1hdR1k6Ulwe2JZD50LpXyWPEAeP88vLNO97I")
    CkStringBuilder::ckAppend(sbJwk,"jlA7_GQ5sLKMgvfTeXZx9SE-7YwVol2NXOoAJe46sui395IW_GO-pWJ1O0")
    CkStringBuilder::ckAppend(sbJwk,"BkTGoVEn2bKVRUCgu-GjBVaYLU6f3l9kJfFNS3E0QbVdxzubSu3Mkqzjkn")
    CkStringBuilder::ckAppend(sbJwk,"439X0M_V51gfpRLI9JYanrC4D4qAdGcopV_0ZHHzQlBjudU2QvXt4ehNYT")
    CkStringBuilder::ckAppend(sbJwk,"CBr6XCLQUShb1juUO1ZdiYoFaFQT5Tw8bGUl_x_jTj3ccPDVZFD9pIuhLh")
    CkStringBuilder::ckAppend(sbJwk,"BOneufuBiB4cS98l2SR_RQyGWSeWjnczT0QU91p1DhOVRuOopznQ" + Chr(34) + ",")
    CkStringBuilder::ckAppend(sbJwk,Chr(34) + "p" + Chr(34) + ":" + Chr(34) + "4BzEEOtIpmVdVEZNCqS7baC4crd0pqnRH_5IB3jw3bcxGn6QLvnEtfdUdi")
    CkStringBuilder::ckAppend(sbJwk,"YrqBdss1l58BQ3KhooKeQTa9AB0Hw_Py5PJdTJNPY8cQn7ouZ2KKDcmnPG")
    CkStringBuilder::ckAppend(sbJwk,"BY5t7yLc1QlQ5xHdwW1VhvKn-nXqhJTBgIPgtldC-KDV5z-y2XDwGUc" + Chr(34) + ",")
    CkStringBuilder::ckAppend(sbJwk,Chr(34) + "q" + Chr(34) + ":" + Chr(34) + "uQPEfgmVtjL0Uyyx88GZFF1fOunH3-7cepKmtH4pxhtCoHqpWmT8YAmZxa")
    CkStringBuilder::ckAppend(sbJwk,"ewHgHAjLYsp1ZSe7zFYHj7C6ul7TjeLQeZD_YwD66t62wDmpe_HlB-TnBA")
    CkStringBuilder::ckAppend(sbJwk,"-njbglfIsRLtXlnDzQkv5dTltRJ11BKBBypeeF6689rjcJIDEz9RWdc" + Chr(34) + ",")
    CkStringBuilder::ckAppend(sbJwk,Chr(34) + "dp" + Chr(34) + ":" + Chr(34) + "BwKfV3Akq5_MFZDFZCnW-wzl-CCo83WoZvnLQwCTeDv8uzluRSnm71I3Q")
    CkStringBuilder::ckAppend(sbJwk,"CLdhrqE2e9YkxvuxdBfpT_PI7Yz-FOKnu1R6HsJeDCjn12Sk3vmAktV2zb")
    CkStringBuilder::ckAppend(sbJwk,"34MCdy7cpdTh_YVr7tss2u6vneTwrA86rZtu5Mbr1C1XsmvkxHQAdYo0" + Chr(34) + ",")
    CkStringBuilder::ckAppend(sbJwk,Chr(34) + "dq" + Chr(34) + ":" + Chr(34) + "h_96-mK1R_7glhsum81dZxjTnYynPbZpHziZjeeHcXYsXaaMwkOlODsWa")
    CkStringBuilder::ckAppend(sbJwk,"7I9xXDoRwbKgB719rrmI2oKr6N3Do9U0ajaHF-NKJnwgjMd2w9cjz3_-ky")
    CkStringBuilder::ckAppend(sbJwk,"NlxAr2v4IKhGNpmM5iIgOS1VZnOZ68m6_pbLBSp3nssTdlqvd0tIiTHU" + Chr(34) + ",")
    CkStringBuilder::ckAppend(sbJwk,Chr(34) + "qi" + Chr(34) + ":" + Chr(34) + "IYd7DHOhrWvxkwPQsRM2tOgrjbcrfvtQJipd-DlcxyVuuM9sQLdgjVk2o")
    CkStringBuilder::ckAppend(sbJwk,"y26F0EmpScGLq2MowX7fhd_QJQ3ydy5cY7YIBi87w93IKLEdfnbJtoOPLU")
    CkStringBuilder::ckAppend(sbJwk,"W0ITrJReOgo1cq9SbsxYawBgfp_gh6A5603k2-ZQwVK0JKSHuLFkuQ3U" + Chr(34))
    CkStringBuilder::ckAppend(sbJwk,"}")

    rsaKey.i = CkPrivateKey::ckCreate()
    If rsaKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Note: This example loads the RSA key from JWK format.  Any format can be loaded
    ; into the private key object. (See the online reference documentation..)
    success = CkPrivateKey::ckLoadJwk(rsaKey,CkStringBuilder::ckGetAsString(sbJwk))
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(rsaKey)
        CkStringBuilder::ckDispose(sbJwk)
        CkPrivateKey::ckDispose(rsaKey)
        ProcedureReturn
    EndIf

    ; Create the JWS Protected Header
    jwsProtHdr.i = CkJsonObject::ckCreate()
    If jwsProtHdr.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckAppendString(jwsProtHdr,"alg","PS256")

    jws.i = CkJws::ckCreate()
    If jws.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Set the protected header:
    signatureIndex.i = 0
    CkJws::ckSetProtectedHeader(jws,signatureIndex,jwsProtHdr)

    ; Set the RSA key:
    CkJws::ckSetPrivateKey(jws,signatureIndex,rsaKey)

    ; Set the payload.
    bIncludeBom.i = 0
    payloadStr.s = "In our village, folks say God crumbles up the old moon into stars."
    CkJws::ckSetPayload(jws,payloadStr,"utf-8",bIncludeBom)

    ; Create the JWS
    ; By default, the compact serialization is used.
    jwsCompact.s = CkJws::ckCreateJws(jws)
    If CkJws::ckLastMethodSuccess(jws) = 0
        Debug CkJws::ckLastErrorText(jws)
        CkStringBuilder::ckDispose(sbJwk)
        CkPrivateKey::ckDispose(rsaKey)
        CkJsonObject::ckDispose(jwsProtHdr)
        CkJws::ckDispose(jws)
        ProcedureReturn
    EndIf

    Debug "JWS: " + jwsCompact

    ; Note: RSA PSS padding uses random values, so the output will be different each time a signature is produced.
    ; sample output:
    ; JWS: eyJhbGciOiJQUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.TRWhwRo5dMv9-8OzrInfJTwmUGYgjLfHk8lqF072ND-FmLWEBnUTOpY8oJXp8FdWw2SalbdOeNlrtlJjwk4XK8Ql2iJ_2qMCtxsvLPhKBOqFoAF4aBvTOEDVJDxf0DaBSiydEEtfTVV2iwBcjWabu5J2XieR5y7QZQtuHsn7T3qKBvCcCejN3Y2oqAT3qMHvu1fTms1r_91wBn_K7Wjd9UkZ1n02qQcUHJznR_OF2BgN7_KWIDAF9ZS9keoju2NPpPelO4yxa2XUPnehY3G7dHKoCxUEQR4d2Xc5voqDASTVCDqQS4PVOZdvT3Ein6-SanAlCwbWBbkvT8g6-5PImQ

    ; Now load the JWS, validate, and recover the original text.
    jws2.i = CkJws::ckCreate()
    If jws2.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Load the JWS.
    success = CkJws::ckLoadJws(jws2,jwsCompact)

    rsaPubKey.i = CkPublicKey::ckCreate()
    If rsaPubKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkPrivateKey::ckToPublicKey(rsaKey,rsaPubKey)

    ; Set the RSA public key used for validation.
    signatureIndex = 0
    CkJws::ckSetPublicKey(jws2,signatureIndex,rsaPubKey)

    ; Validate the 1st (and only) signature at index 0..
    v.i = CkJws::ckValidate(jws2,signatureIndex)
    If v < 0
        ; Perhaps Chilkat was not unlocked or the trial expired..
        Debug "Method call failed for some other reason."
        Debug CkJws::ckLastErrorText(jws2)
        CkStringBuilder::ckDispose(sbJwk)
        CkPrivateKey::ckDispose(rsaKey)
        CkJsonObject::ckDispose(jwsProtHdr)
        CkJws::ckDispose(jws)
        CkJws::ckDispose(jws2)
        CkPublicKey::ckDispose(rsaPubKey)
        ProcedureReturn
    EndIf

    If v = 0
        Debug "Invalid signature.  The RSA key was incorrect, the JWS was invalid, or both."
        CkStringBuilder::ckDispose(sbJwk)
        CkPrivateKey::ckDispose(rsaKey)
        CkJsonObject::ckDispose(jwsProtHdr)
        CkJws::ckDispose(jws)
        CkJws::ckDispose(jws2)
        CkPublicKey::ckDispose(rsaPubKey)
        ProcedureReturn
    EndIf

    ; If we get here, the signature was validated..
    Debug "Signature validated."

    ; Recover the original content:
    Debug CkJws::ckGetPayload(jws2,"utf-8")

    ; Examine the protected header:
    joseHeader.i = CkJsonObject::ckCreate()
    If joseHeader.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJws::ckGetProtectedH(jws2,signatureIndex,joseHeader)
    CkJsonObject::setCkEmitCompact(joseHeader, 0)

    Debug "Protected (JOSE) header:"
    Debug CkJsonObject::ckEmit(joseHeader)

    ; Output:

    ; 	Signature validated.
    ; 	In our village, folks say God crumbles up the old moon into stars.
    ; 	Protected (JOSE) header:
    ; 	{ 
    ; 	  "alg": "PS256"
    ; 	}


    CkStringBuilder::ckDispose(sbJwk)
    CkPrivateKey::ckDispose(rsaKey)
    CkJsonObject::ckDispose(jwsProtHdr)
    CkJws::ckDispose(jws)
    CkJws::ckDispose(jws2)
    CkPublicKey::ckDispose(rsaPubKey)
    CkJsonObject::ckDispose(joseHeader)


    ProcedureReturn
EndProcedure