issuer-example/exa-client.ts at main · exactly/issuer-example · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
import {
  checksumAddress,
  createPublicClient,
  encodeAbiParameters,
  encodeFunctionData,
  encodePacked,
  hashMessage,
  http,
  keccak256,
  padHex,
  parseAbi,
  parseAbiParameters,
  serializeErc6492Signature,
  slice,
  type Address,
  type Chain,
  type LocalAccount,
} from "viem";

import { createSiweMessage } from "viem/siwe";

export function createMessage({
  chainId,
  factory,
  host,
  last4,
  nonce,
  userId,
  x,
  y,
}: {
  chainId: number;
  factory: Address;
  host: string;
  last4: string;
  nonce: string;
  userId: string;
  x: bigint;
  y: bigint;
}) {
  const issuedAt = new Date();
  return createSiweMessage({
    statement: `I authorize this account to be linked with the card ending in ${last4} for my user (${userId})`,
    uri: `https://${host}/v1/issuing/users/${userId}/signatures/verify`,
    expirationTime: new Date(issuedAt.getTime() + 5 * 60_000),
    address: deriveAddress({ factory, x, y }),
    domain: host,
    scheme: "https",
    version: "1",
    issuedAt,
    chainId,
    nonce,
  });
}

export async function signMessage({
  chain,
  factory,
  message,
  owner,
  x,
  y,
}: {
  chain: Chain;
  factory: Address;
  message: string;
  owner: Pick<LocalAccount, "signTypedData">;
  x: bigint;
  y: bigint;
}) {
  const account = deriveAddress({ factory, x, y });
  const factoryData = encodeFunctionData({
    functionName: "createAccount",
    args: [0n, [{ x, y }]],
    abi: parseAbi(["function createAccount(uint256 salt, (uint256 x, uint256 y)[] owners) returns (address)"]),
  });
  const plugins = await createPublicClient({ chain, transport: http() }).readContract({
    address: account,
    functionName: "getInstalledPlugins",
    abi: parseAbi(["function getInstalledPlugins() view returns (address[])"]),
    factoryData,
    factory,
  });
  const ownerPlugin = plugins.at(-1);
  if (!ownerPlugin) throw new Error("missing plugin");
  return {
    account,
    signature: serializeErc6492Signature({
      address: factory,
      data: factoryData,
      signature: encodePacked(
        ["uint8", "bytes"],
        [
          0,
          await owner.signTypedData({
            domain: {
              chainId: chain.id,
              name: "Webauthn Owner Plugin",
              version: "1.0.0",
              verifyingContract: account,
              salt: padHex(ownerPlugin, { dir: "right" }),
            },
            types: { AlchemyModularAccountMessage: [{ name: "message", type: "bytes" }] },
            primaryType: "AlchemyModularAccountMessage",
            message: { message: encodeAbiParameters(parseAbiParameters("bytes32"), [hashMessage(message)]) },
          }),
        ],
      ),
    }),
  };
}

function deriveAddress({ factory, x, y }: { factory: Address; x: bigint; y: bigint }) {
  const accountImplementation = "0x0046000000000151008789797b54fdb500E2a61e";
  const initCodeHashERC1967 = keccak256(
    encodePacked(
      ["bytes", "address", "bytes"],
      [
        "0x603d3d8160223d3973",
        accountImplementation,
        "0x60095155f3363d3d373d3d363d7f360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc545af43d6000803e6038573d6000fd5b3d6000f3",
      ],
    ),
  );
  return checksumAddress(
    slice(
      keccak256(
        encodePacked(
          ["uint8", "address", "bytes32", "bytes32"],
          [
            0xff,
            factory,
            keccak256(
              encodeAbiParameters(parseAbiParameters("uint256, bytes"), [
                0n,
                encodeAbiParameters(parseAbiParameters("(uint256 x, uint256 y)[]"), [[{ x, y }]]),
              ]),
            ),
            initCodeHashERC1967,
          ],
        ),
      ),
      12,
    ),
  );
}