From 27e58dc4ad3d9f261e24852e6ee6960f5b9d3962 Mon Sep 17 00:00:00 2001
From: Anton Biriukov <anton.biriukov@avast.com>
Date: Fri, 4 Nov 2022 15:00:20 +0100
Subject: [PATCH] feat: implemented OIDC presentation submission API

Signed-off-by: Anton Biriukov <anton.biriukov@avast.com>
---
 .../src/oidc/presentation/openid4vp.js        | 175 +++++++++++++++++-
 1 file changed, 174 insertions(+), 1 deletion(-)

diff --git a/cmd/wallet-js-sdk/src/oidc/presentation/openid4vp.js b/cmd/wallet-js-sdk/src/oidc/presentation/openid4vp.js
index c1676518..64c4714d 100644
--- a/cmd/wallet-js-sdk/src/oidc/presentation/openid4vp.js
+++ b/cmd/wallet-js-sdk/src/oidc/presentation/openid4vp.js
@@ -6,9 +6,13 @@ SPDX-License-Identifier: Apache-2.0
 */
 
 import axios from "axios";
-import { decode } from "js-base64";
+import { decode, encode } from "js-base64";
 import { CredentialManager, DIDManager } from "@";
 import * as jose from "jose";
+import { generateNonce } from "@/util/helper";
+
+const ID_TOKEN_EXPIRY = 10 * 60; // 10 minutes
+const VP_TOKEN_EXPIRY = 10 * 60; // 10 minutes
 
 /**
  *  OpenID4VP module is the oidc client that provides APIs for OIDC4VP flows.
@@ -120,6 +124,175 @@ export class OpenID4VP {
         }
       });
 
+    this.client_id = payload.client_id;
+    this.nonce = payload.nonce;
+    this.redirect_uri = payload.redirect_uri;
+
     return response.results;
   }
+
+  async submitOIDCPresentation(
+    presentationQuery,
+    sign = async function (iss, aud, iat, nonce) {
+      return "";
+    }
+  ) {
+    if (!presentationQuery) {
+      throw new TypeError(
+        "Error submitting OpenID4VP presentation: presentationQuery cannot be empty"
+      );
+    } else if (!presentationQuery.presentation_submission) {
+      throw new TypeError(
+        "Error submitting OpenID4VP presentation: presentation_submission is missing"
+      );
+    } else if (!presentationQuery.type) {
+      throw new TypeError(
+        "Error submitting OpenID4VP presentation: type is missing"
+      );
+    } else if (!presentationQuery.verifiableCredential) {
+      throw new TypeError(
+        "Error submitting OpenID4VP presentation: verifiableCredential is missing"
+      );
+    }
+
+    const header = new Object();
+    Object.defineProperty(header, "alg", {
+      value: alg,
+    });
+    Object.defineProperty(header, "kid", {
+      // TODO: clarify where we get this param from
+      value: kid,
+    });
+    Object.defineProperty(header, "typ", {
+      value: "JWT",
+    });
+
+    const encodedHeader = encode(JSON.stringify(header), true);
+
+    const id_token = await generateIdToken(
+      presentationQuery.presentation_submission,
+      encodedHeader,
+      (sign = async function (iss, aud, iat, nonce) {
+        return "";
+      })
+    );
+
+    const vp = new Object();
+    Object.defineProperty(payload, "@context", {
+      value: presentationQuery["@context"],
+    });
+    Object.defineProperty(payload, "type", {
+      value: presentationQuery.type,
+    });
+    Object.defineProperty(payload, "verifiableCredential", {
+      value: presentationQuery.verifiableCredential,
+    });
+
+    const vp_token = await generateVpToken(
+      encodedHeader,
+      vp,
+      (sign = async function (iss, aud, iat, nonce) {
+        return "";
+      })
+    );
+
+    const authRequest = new URLSearchParams();
+    authRequest.append("id_token", id_token);
+    authRequest.append("vp_token", vp_token);
+
+    return await axios.post(this.redirect_uri, authRequest).catch((e) => {
+      throw new Error("Error submitting OIDC presentation:", e);
+    });
+  }
+}
+
+async function generateIdToken(
+  presentation_submission,
+  encodedHeader,
+  sign = async function (iss, aud, iat, nonce) {
+    return "";
+  }
+) {
+  if (!presentation_submission) {
+    throw new TypeError(
+      "Error generating ID Token: presentation_submission is be empty"
+    );
+  }
+
+  const vpToken = new Object();
+  Object.defineProperty(vpToken, "presentation_submission", {
+    value: presentation_submission,
+  });
+
+  const iat = new Date().getTime() / 1000;
+
+  const payload = new Object();
+  // TODO: dynamically pass sub
+  Object.defineProperty(payload, "sub", {
+    value: "sub",
+  });
+  Object.defineProperty(payload, "nonce", {
+    value: this.nonce,
+  });
+  Object.defineProperty(payload, "_vp_token", {
+    value: vpToken,
+  });
+  Object.defineProperty(payload, "aud", {
+    value: this.client_id,
+  });
+  Object.defineProperty(payload, "iss", {
+    value: iss,
+  });
+  Object.defineProperty(payload, "iat", {
+    value: iat,
+  });
+  Object.defineProperty(payload, "exp", {
+    value: iat + ID_TOKEN_EXPIRY,
+  });
+
+  const encodedPayload = encode(JSON.stringify(payload), true);
+
+  const signature = await sign(kid, this.client_id, iat, this.nonce);
+
+  return `${encodedHeader}.${encodedPayload}.${signature}`;
+}
+
+async function generateVpToken(
+  encodedHeader,
+  vp,
+  sign = async function (iss, aud, iat, nonce) {
+    return "";
+  }
+) {
+  const iat = new Date().getTime() / 1000;
+  const payload = new Object();
+  Object.defineProperty(payload, "nonce", {
+    value: this.nonce,
+  });
+  Object.defineProperty(payload, "vp", {
+    value: vp,
+  });
+  Object.defineProperty(payload, "aud", {
+    // TODO: clarify where we get this param from
+    value: "",
+  });
+  Object.defineProperty(payload, "iss", {
+    // TODO: clarify where we get this param from
+    value: "",
+  });
+  Object.defineProperty(payload, "iat", {
+    value: iat,
+  });
+  Object.defineProperty(payload, "nbf", {
+    value: iat,
+  });
+  Object.defineProperty(payload, "exp", {
+    value: iat + VP_TOKEN_EXPIRY,
+  });
+
+  const encodedPayload = encode(JSON.stringify(payload), true);
+
+  const signature = await sign(kid, this.client_id, iat, this.nonce);
+
+  return `${encodedHeader}.${encodedPayload}.${signature}`;
 }