Class SignedData

Represents the SignedData structure described in RFC5652

Example

The following example demonstrates how to create and sign CMS Signed Data

// Create a new CMS Signed Data
const cmsSigned = new pkijs.SignedData({
  encapContentInfo: new pkijs.EncapsulatedContentInfo({
    eContentType: pkijs.ContentInfo.DATA,, // "data" content type
    eContent: new asn1js.OctetString({ valueHex: buffer })
  }),
  signerInfos: [
    new pkijs.SignerInfo({
      sid: new pkijs.IssuerAndSerialNumber({
        issuer: cert.issuer,
        serialNumber: cert.serialNumber
      })
    })
  ],
  // Signer certificate for chain validation
  certificates: [cert]
});

await cmsSigned.sign(keys.privateKey, 0, "SHA-256");

// Add Signed Data to Content Info
const cms = new pkijs.ContentInfo({
  contentType: pkijs.ContentInfo.SIGNED_DATA,,
  content: cmsSigned.toSchema(true),
});

// Encode CMS to ASN.1
const cmsRaw = cms.toSchema().toBER();

Example

The following example demonstrates how to verify CMS Signed Data

// Parse CMS and detect it's Signed Data
const cms = pkijs.ContentInfo.fromBER(cmsRaw);
if (cms.contentType !== pkijs.ContentInfo.SIGNED_DATA) {
  throw new Error("CMS is not Signed Data");
}

// Read Signed Data
const signedData = new pkijs.SignedData({ schema: cms.content });

// Verify Signed Data signature
const ok = await signedData.verify({
  signer: 0,
  checkChain: true,
  trustedCerts: [trustedCert],
});

if (!ok) {
  throw new Error("CMS signature is invalid")
}