| 1 | import { CircleX, KeyRound } from "lucide-react"; |
| 2 | import { Form, redirect } from "react-router"; |
| 3 | |
| 4 | import { decodeOAuthClient, isRegisteredRedirect } from "@g1t/contracts"; |
| 5 | |
| 6 | import type { Route } from "./+types/oauth-authorize"; |
| 7 | import { page } from "../lib/meta"; |
| 8 | import { ErrorText, SubmitButton, usePending } from "../components/ui"; |
| 9 | import { ScopeChecklist } from "../components/token-scopes"; |
| 10 | import { identity } from "../lib/services.server"; |
| 11 | import { addresses } from "../lib/addresses.server"; |
| 12 | import { consentedScopes, requestedScopes } from "../lib/token-scopes"; |
| 13 | import { assertSameOrigin, requireUser } from "../lib/session.server"; |
| 14 | |
| 15 | export function meta(args: Route.MetaArgs) { |
| 16 | return page(args, { title: "Sign in to an application · g1t" }); |
| 17 | } |
| 18 | |
| 19 | type Checked = |
| 20 | | { ok: false; problem: string } |
| 21 | | { |
| 22 | ok: true; |
| 23 | clientId: string; |
| 24 | clientName: string; |
| 25 | redirectUri: string; |
| 26 | codeChallenge: string; |
| 27 | state: string; |
| 28 | }; |
| 29 | |
| 30 | /** |
| 31 | * Checks an authorization request. A request that names a client or a |
| 32 | * redirect address we cannot vouch for is never redirected anywhere; the |
| 33 | * person is told instead. |
| 34 | */ |
| 35 | function check(params: URLSearchParams | FormData): Checked { |
| 36 | const get = (key: string) => String(params.get(key) ?? ""); |
| 37 | const client = decodeOAuthClient(get("client_id")); |
| 38 | if (!client) { |
| 39 | return { ok: false, problem: "This sign-in link names an application g1t does not recognise." }; |
| 40 | } |
| 41 | const redirectUri = get("redirect_uri") || client.redirectUris[0]; |
| 42 | if (!isRegisteredRedirect(client, redirectUri)) { |
| 43 | return { |
| 44 | ok: false, |
| 45 | problem: "This sign-in link would send you somewhere the application did not register.", |
| 46 | }; |
| 47 | } |
| 48 | if (get("response_type") !== "code") { |
| 49 | return { ok: false, problem: "This sign-in link asks for a kind of access g1t does not offer." }; |
| 50 | } |
| 51 | if (!get("code_challenge") || get("code_challenge_method") !== "S256") { |
| 52 | return { |
| 53 | ok: false, |
| 54 | problem: "This application did not protect its sign-in with PKCE (S256), which g1t requires.", |
| 55 | }; |
| 56 | } |
| 57 | return { |
| 58 | ok: true, |
| 59 | clientId: get("client_id"), |
| 60 | clientName: client.name, |
| 61 | redirectUri, |
| 62 | codeChallenge: get("code_challenge"), |
| 63 | state: get("state"), |
| 64 | }; |
| 65 | } |
| 66 | |
| 67 | /** The application's redirect address with the outcome added to it. */ |
| 68 | function callback(redirectUri: string, params: Record<string, string>): string { |
| 69 | const url = new URL(redirectUri); |
| 70 | for (const [key, value] of Object.entries(params)) { |
| 71 | if (value) url.searchParams.set(key, value); |
| 72 | } |
| 73 | return url.toString(); |
| 74 | } |
| 75 | |
| 76 | /** Where an application sends a person to approve its sign-in. */ |
| 77 | export function loader({ request, context }: Route.LoaderArgs) { |
| 78 | const user = requireUser(context, request); |
| 79 | const { searchParams } = new URL(request.url); |
| 80 | return { |
| 81 | user, |
| 82 | request: check(searchParams), |
| 83 | // What the application asked for; nothing usable means the default set. |
| 84 | requested: requestedScopes(searchParams.get("scope")), |
| 85 | // Sent back unchanged when the person decides. |
| 86 | query: Object.fromEntries(searchParams), |
| 87 | }; |
| 88 | } |
| 89 | |
| 90 | export async function action({ request, context }: Route.ActionArgs) { |
| 91 | assertSameOrigin(request); |
| 92 | const user = requireUser(context, request); |
| 93 | const form = await request.formData(); |
| 94 | const checked = check(form); |
| 95 | if (!checked.ok) return null; |
| 96 | if (form.get("decision") !== "approve") { |
| 97 | throw redirect( |
| 98 | callback(checked.redirectUri, { error: "access_denied", state: checked.state }), |
| 99 | ); |
| 100 | } |
| 101 | // Only what the application asked for, never more, whatever the form says. |
| 102 | const scopes = consentedScopes(form, requestedScopes(String(form.get("scope") ?? ""))); |
| 103 | if (scopes.length === 0) { |
| 104 | return { error: "Leave at least one box ticked, or deny." }; |
| 105 | } |
| 106 | const { code } = await identity.oauthAuthorize(user, { |
| 107 | clientId: checked.clientId, |
| 108 | clientName: checked.clientName, |
| 109 | redirectUri: checked.redirectUri, |
| 110 | codeChallenge: checked.codeChallenge, |
| 111 | scopes, |
| 112 | }); |
| 113 | // `iss` is the API's origin, the issuer its metadata names (RFC 9207). |
| 114 | throw redirect( |
| 115 | callback(checked.redirectUri, { code, state: checked.state, iss: addresses().api }), |
| 116 | ); |
| 117 | } |
| 118 | |
| 119 | export default function Authorize({ loaderData, actionData }: Route.ComponentProps) { |
| 120 | const { user, request, requested, query } = loaderData; |
| 121 | // Either answer turns both buttons off until it is in. |
| 122 | const deciding = usePending(); |
| 123 | |
| 124 | if (!request.ok) { |
| 125 | return ( |
| 126 | <main className="mx-auto max-w-md px-4 py-32 text-center"> |
| 127 | <CircleX size={40} className="mx-auto text-muted" /> |
| 128 | <h1 className="mt-6 text-2xl font-semibold tracking-tight">This link cannot be used</h1> |
| 129 | <p className="mt-2 text-muted">{request.problem}</p> |
| 130 | <p className="mt-2 text-sm text-faint">Nothing was given access to your account.</p> |
| 131 | </main> |
| 132 | ); |
| 133 | } |
| 134 | |
| 135 | const destination = new URL(request.redirectUri); |
| 136 | return ( |
| 137 | <main className="mx-auto max-w-md px-4 py-24"> |
| 138 | <KeyRound size={36} className="text-accent" /> |
| 139 | <h1 className="mt-6 text-2xl font-semibold tracking-tight"> |
| 140 | Sign in to {request.clientName} |
| 141 | </h1> |
| 142 | <p className="mt-2 text-muted"> |
| 143 | <span className="font-medium text-fg">{request.clientName}</span> wants to act as{" "} |
| 144 | <span className="font-mono font-medium text-fg">{user.username}</span> on g1t. |
| 145 | </p> |
| 146 | |
| 147 | <Form method="post" className="mt-6 space-y-6"> |
| 148 | {Object.entries(query).map(([name, value]) => ( |
| 149 | <input key={name} type="hidden" name={name} value={value} /> |
| 150 | ))} |
| 151 | <section> |
| 152 | <h2 className="text-sm font-medium">It will be able to</h2> |
| 153 | <p className="mt-0.5 text-xs text-faint"> |
| 154 | Everywhere you can, as you. Untick anything you would rather it could not do. |
| 155 | </p> |
| 156 | <div className="mt-3"> |
| 157 | <ScopeChecklist initial={requested} only={requested} allowFull={false} /> |
| 158 | </div> |
| 159 | </section> |
| 160 | <dl className="rounded-xl border border-line bg-surface p-4 text-sm"> |
| 161 | <dt className="text-xs text-faint">You will be sent back to</dt> |
| 162 | <dd className="mt-0.5 font-mono text-[0.8125rem] break-all"> |
| 163 | {destination.protocol === "https:" || destination.protocol === "http:" |
| 164 | ? destination.host + destination.pathname |
| 165 | : request.redirectUri} |
| 166 | </dd> |
| 167 | </dl> |
| 168 | <div> |
| 169 | <p className="text-xs text-faint"> |
| 170 | Approve only if you started this from {request.clientName} yourself. You can change |
| 171 | what it may do, or sign it out, in Settings. |
| 172 | </p> |
| 173 | <ErrorText>{actionData?.error}</ErrorText> |
| 174 | <div className="mt-4 flex gap-2"> |
| 175 | <SubmitButton variant="accent" name="decision" value="approve" pending="Approving…" disabled={deciding}> |
| 176 | Approve |
| 177 | </SubmitButton> |
| 178 | <SubmitButton variant="quiet" name="decision" value="deny" pending="Denying…" disabled={deciding}> |
| 179 | Deny |
| 180 | </SubmitButton> |
| 181 | </div> |
| 182 | </div> |
| 183 | </Form> |
| 184 | </main> |
| 185 | ); |
| 186 | } |