feat: patched up regex issues

backend/src/lib/certificates/extract-certificate.test.ts

@@ -0,0 +1,42 @@
+import { extractX509CertFromChain } from "./extract-certificate";
+
+describe("Extract Certificate Payload", () => {
+  test("Single chain", () => {
+    const payload = `-----BEGIN CERTIFICATE-----
+MIIEZzCCA0+gAwIBAgIUDk9+HZcMHppiNy0TvoBg8/aMEqIwDQYJKoZIhvcNAQEL
+BQAwDTELMAkGA1UEChMCUEgwHhcNMjQxMDI1MTU0MjAzWhcNMjUxMDI1MjE0MjAz
+-----END CERTIFICATE-----`;
+    const result = extractX509CertFromChain(payload);
+    expect(result).toBeDefined();
+    expect(result?.length).toBe(1);
+    expect(result?.[0]).toEqual(payload);
+  });
+
+  test("Multiple chain", () => {
+    const payload = `-----BEGIN CERTIFICATE-----
+MIIEZzCCA0+gAwIBAgIUDk9+HZcMHppiNy0TvoBg8/aMEqIwDQYJKoZIhvcNAQEL
+BQAwDTELMAkGA1UEChMCUEgwHhcNMjQxMDI1MTU0MjAzWhcNMjUxMDI1MjE0MjAz
+-----END CERTIFICATE-----
+-----BEGIN CERTIFICATE-----
+MIIEZzCCA0+gAwIBAgIUDk9+HZcMHppiNy0TvoBg8/aMEqIwDQYJKoZIhvcNAQEL
+-----END CERTIFICATE-----
+-----BEGIN CERTIFICATE-----
+MIIEZzCCA0+gAwIBAgIUDk9+HZcMHppiNy0TvoBg8/aMEqIwDQYJKoZIhvcNAQEL
+-----END CERTIFICATE-----`;
+    const result = extractX509CertFromChain(payload);
+    expect(result).toBeDefined();
+    expect(result?.length).toBe(3);
+    expect(result).toEqual([
+      `-----BEGIN CERTIFICATE-----
+MIIEZzCCA0+gAwIBAgIUDk9+HZcMHppiNy0TvoBg8/aMEqIwDQYJKoZIhvcNAQEL
+BQAwDTELMAkGA1UEChMCUEgwHhcNMjQxMDI1MTU0MjAzWhcNMjUxMDI1MjE0MjAz
+-----END CERTIFICATE-----`,
+      `-----BEGIN CERTIFICATE-----
+MIIEZzCCA0+gAwIBAgIUDk9+HZcMHppiNy0TvoBg8/aMEqIwDQYJKoZIhvcNAQEL
+-----END CERTIFICATE-----`,
+      `-----BEGIN CERTIFICATE-----
+MIIEZzCCA0+gAwIBAgIUDk9+HZcMHppiNy0TvoBg8/aMEqIwDQYJKoZIhvcNAQEL
+-----END CERTIFICATE-----`
+    ]);
+  });
+});

backend/src/lib/certificates/extract-certificate.ts

@@ -0,0 +1,51 @@
+import { BadRequestError } from "../errors";
+
+export const extractX509CertFromChain = (certificateChain: string): string[] => {
+  if (!certificateChain) {
+    throw new BadRequestError({
+      message: "Certificate chain is empty or undefined"
+    });
+  }
+
+  const certificates: string[] = [];
+  let currentPosition = 0;
+  const chainLength = certificateChain.length;
+
+  while (currentPosition < chainLength) {
+    // Find the start of a certificate
+    const beginMarker = "-----BEGIN CERTIFICATE-----";
+    const startIndex = certificateChain.indexOf(beginMarker, currentPosition);
+
+    if (startIndex === -1) {
+      break; // No more certificates found
+    }
+
+    // Find the end of the certificate
+    const endMarker = "-----END CERTIFICATE-----";
+    const endIndex = certificateChain.indexOf(endMarker, startIndex);
+
+    if (endIndex === -1) {
+      throw new BadRequestError({
+        message: "Malformed certificate chain: Found BEGIN marker without matching END marker"
+      });
+    }
+
+    // Extract the complete certificate including markers
+    const completeEndIndex = endIndex + endMarker.length;
+    const certificate = certificateChain.substring(startIndex, completeEndIndex);
+
+    // Add the extracted certificate to our results
+    certificates.push(certificate);
+
+    // Move position to after this certificate
+    currentPosition = completeEndIndex;
+  }
+
+  if (certificates.length === 0) {
+    throw new BadRequestError({
+      message: "No valid certificates found in the chain"
+    });
+  }
+
+  return certificates;
+};