webRequest.getSecurityInfo()

Use this function to get detailed information about the TLS connection associated with a particular request.

You pass this function the requestId for the request in question, and some optional extra parameters. It returns a Promise which will resolve to a SecurityInfo object.

You can only call this function from inside the webRequest.onHeadersReceived listener. The requestId can be found in the details object which is passed into the listener.

You must also pass the "blocking" option to webRequest.onHeadersReceived.addListener(). So to use this API you must have the "webRequestBlocking" API permission, as well as the normal permissions needed for using webRequest listeners (the "webRequest" permission and the host permission for the host).

Syntax

var gettingInfo = browser.webRequest.getSecurityInfo(
  requestId,       // string
  options          // object
)

Parameters

requestId

string. ID of the request for which you want security info. You can get this from the details object that is passed into any webRequest event listeners.

options

object. An object which may contain any of the following properties, all optional:

certificateChain Optional

boolean. If true, the SecurityInfo object returned will include the entire certificate chain up to and including the trust root. If false, it will include only the server certificate. Defaults to false.

rawDER Optional

boolean. If true, every CertificateInfo in the SecurityInfo.certificates property will contain a property rawDER. This contains the DER-encoded ASN.1 that comprises the certificate data.

Return value

A Promise which resolves to a SecurityInfo object.

Browser compatibility

Examples

This example listens for all HTTPS requests to "mozilla.org" or its subdomains, and logs the subject name in the server certificate:

async function logSubject(details) {
  try {
    let securityInfo = await browser.webRequest.getSecurityInfo(details.requestId, {});
    console.log(details.url);
    if (securityInfo.state === "secure" || securityInfo.state === "weak") {
      console.log(securityInfo.certificates[0].subject);
    }
  }
  catch(error) {
    console.error(error);
  }
}

browser.webRequest.onHeadersReceived.addListener(logSubject,
  {urls: ["https://*.mozilla.org/*"]},
  ["blocking"]
);

This example listens for all HTTPS requests to "mozilla.org" or its subdomains, and logs the name in the trusted root certificate:

async function logRoot(details) {
  try {
    let securityInfo = await browser.webRequest.getSecurityInfo(
      details.requestId,
      {"certificateChain": true}
    );
    console.log(details.url);
    if (securityInfo.state === "secure" || securityInfo.state === "weak") {
      console.log(securityInfo.certificates[securityInfo.certificates.length - 1].issuer);
    }
  }
  catch(error) {
    console.error(error);
  }
}

browser.webRequest.onHeadersReceived.addListener(logRoot,
  {urls: ["https://*.mozilla.org/*"]},
  ["blocking"]
);

Example extensions

• root-cert-stats