Start DMs

frontend/src/api/dmApi.ts

@@ -0,0 +1,122 @@
+import { API_BASE_URL } from "../core/config";
+import { getAuthHeaders } from "../auth/api";
+import { ecdhSharedSecret, deriveWrappingKey } from "../crypto/asymmetric";
+import { importAesGcmKey, aesGcmEncrypt, aesGcmDecrypt } from "../crypto/symmetric";
+import { randomBytes } from "../crypto/kdf";
+import { getCurrentKeys } from "../auth/crypto";
+import { request } from "../websocket";
+import type { FetchDMResponse, SendDMRequest, DmEnvelope, User } from "../core/types";
+import { b64, ub64 } from "../utils/utils";
+
+export async function sendDm(recipientId: number, recipientPublicKeyB64: string, plaintext: string, token: string): Promise<void> {
+    const keys = getCurrentKeys();
+    if (!keys) throw new Error("Keys not initialized");
+    const mk = randomBytes(32);
+    const wkSalt = randomBytes(16);
+    const shared = ecdhSharedSecret(keys.privateKey, ub64(recipientPublicKeyB64));
+    const wkRaw = await deriveWrappingKey(shared, wkSalt, new Uint8Array([1]));
+    const wk = await importAesGcmKey(wkRaw);
+    const encMsg = await aesGcmEncrypt(await importAesGcmKey(mk), new TextEncoder().encode(plaintext));
+    const wrap = await aesGcmEncrypt(wk, mk);
+    
+    await fetch(`${API_BASE_URL}/dm/send`, {
+        method: "POST",
+        headers: getAuthHeaders(token, true),
+        body: JSON.stringify({
+            recipientId: recipientId,
+            iv: b64(encMsg.iv),
+            ciphertext: b64(encMsg.ciphertext),
+            salt: b64(wkSalt),
+            iv2: b64(wrap.iv),
+            wrappedMk: b64(wrap.ciphertext)
+        })
+    });
+}
+
+export async function fetchDm(since: number | undefined, token: string): Promise<DmEnvelope[]> {
+    const url = new URL(`${API_BASE_URL}/dm/fetch`);
+    if (since) url.searchParams.set("since", String(since));
+
+    const response = await fetch(url, { 
+        headers: getAuthHeaders(token, true) 
+    });
+
+    if (response.ok) {
+        const data: FetchDMResponse = await response.json();
+        return data.messages ?? [];
+    } else {
+        return [];
+    }
+}
+
+export async function decryptDm(envelope: DmEnvelope, senderPublicKeyB64: string): Promise<string> {
+    const keys = getCurrentKeys();
+    if (!keys) throw new Error("Keys not initialized");
+
+    // Obtain the key
+    const shared = ecdhSharedSecret(keys.privateKey, ub64(senderPublicKeyB64));
+    const wkRaw = await deriveWrappingKey(shared, ub64(envelope.salt), new Uint8Array([1]));
+    const wk = await importAesGcmKey(wkRaw);
+    const mk = await aesGcmDecrypt(wk, ub64(envelope.iv2), ub64(envelope.wrappedMk));
+
+    // Decrypt
+    const msg = await aesGcmDecrypt(await importAesGcmKey(mk), ub64(envelope.iv), ub64(envelope.ciphertext));
+    return new TextDecoder().decode(msg);
+}
+
+export async function fetchUsers(token: string): Promise<User[]> {
+    const res = await fetch(`${API_BASE_URL}/users`, { headers: getAuthHeaders(token, true) });
+    if (!res.ok) return [];
+    const data = await res.json();
+    return data.users || [];
+}
+
+export async function fetchUserPublicKey(userId: number, token: string): Promise<string | null> {
+    const res = await fetch(`${API_BASE_URL}/crypto/public-key/of/${userId}`, { headers: getAuthHeaders(token, true) });
+    if (!res.ok) return null;
+    const data = await res.json();
+    return data.publicKey;
+}
+
+export async function fetchDMHistory(userId: number, token: string, limit: number = 50): Promise<DmEnvelope[]> {
+    const response = await fetch(`${API_BASE_URL}/dm/history/${userId}?limit=${limit}`, { 
+        headers: getAuthHeaders(token, true) 
+    });
+    if (!response.ok) return [];
+    const data = await response.json();
+    return data.messages || [];
+}
+
+export async function sendDMViaWebSocket(recipientId: number, recipientPublicKeyB64: string, plaintext: string, authToken: string): Promise<void> {
+    const keys = getCurrentKeys();
+    if (!keys) throw new Error("Keys not initialized");
+
+    // Encryption key
+    const mk = randomBytes(32);
+    const wkSalt = randomBytes(16);
+    const shared = ecdhSharedSecret(keys.privateKey, ub64(recipientPublicKeyB64));
+    const wkRaw = await deriveWrappingKey(shared, wkSalt, new Uint8Array([1]));
+    const wk = await importAesGcmKey(wkRaw);
+
+    // Encrypt the message
+    const encMsg = await aesGcmEncrypt(await importAesGcmKey(mk), new TextEncoder().encode(plaintext));
+    const wrap = await aesGcmEncrypt(wk, mk);
+
+    const payload: SendDMRequest = {
+        recipientId: recipientId,
+        iv: b64(encMsg.iv),
+        ciphertext: b64(encMsg.ciphertext),
+        salt: b64(wkSalt),
+        iv2: b64(wrap.iv),
+        wrappedMk: b64(wrap.ciphertext)
+    };
+
+    await request({
+        type: "dmSend",
+        credentials: { 
+            scheme: "Bearer", 
+            credentials: authToken
+        },
+        data: payload
+    });
+}