diff options
Diffstat (limited to 'src/features')
| -rw-r--r-- | src/features/messages.js | 87 |
1 files changed, 86 insertions, 1 deletions
diff --git a/src/features/messages.js b/src/features/messages.js index e2d09b6..6f55c02 100644 --- a/src/features/messages.js +++ b/src/features/messages.js @@ -3267,6 +3267,90 @@ export function messagesFeature(ctx) { return h('a', { href: url, target: '_blank', rel: 'noopener noreferrer' }, shown); } + // ---- encrypted attachments (NIP-92 imeta + NIP-17 file fields) ---- + // A picture in a Concord channel never reaches the media server in the + // clear: the sender encrypts it under a one-off key, uploads the blob to + // Blossom, and puts the pointer in an imeta tag โ url, mime, aes-gcm key + // and nonce, the plaintext's sha256 (ox), a size and dimensions. The bubble + // used to show nothing for such a message (its content is empty). Now the + // blob is fetched, decrypted here, checked against the hash, and shown + // from an object URL. A blob that fails the check fails closed. + const ATTACH_MAX = 25 * 1024 * 1024; + const attachCache = new Map(); // url -> { state: 'loading'|'ready'|'error', src, blob } + const parseImeta = (tag) => { + const a = { fallback: [] }; + for (const f of tag.slice(1)) { + const i = f.indexOf(' '); + if (i < 0) continue; + const k = f.slice(0, i), v = f.slice(i + 1); + if (k === 'fallback') a.fallback.push(v); else a[k] = v; + } + return a.url ? a : null; + }; + const attachmentsOf = (rumor) => (rumor.tags || []).filter((t) => t[0] === 'imeta').map(parseImeta).filter(Boolean); + async function loadAttachment(a) { + const entry = { state: 'loading' }; + attachCache.set(a.url, entry); + try { + if (+a.size > ATTACH_MAX) throw new Error('too big'); + let buf = null; + for (const url of [a.url, ...a.fallback]) { + try { + const res = await fetch(url, { mode: 'cors', signal: AbortSignal.timeout(30_000) }); + if (!res.ok) continue; + buf = await res.arrayBuffer(); + if (buf.byteLength > ATTACH_MAX) throw new Error('too big'); + break; + } catch (e) { if (String(e.message).includes('too big')) throw e; } + } + if (!buf) throw new Error('unreachable'); + let bytes = new Uint8Array(buf); + const alg = (a['encryption-algorithm'] || '').toLowerCase(); + if (alg) { + if (alg !== 'aes-gcm' || !a['decryption-key'] || !a['decryption-nonce']) throw new Error('unsupported'); + const key = await crypto.subtle.importKey('raw', hexToBytes(a['decryption-key']), 'AES-GCM', false, ['decrypt']); + bytes = new Uint8Array(await crypto.subtle.decrypt({ name: 'AES-GCM', iv: hexToBytes(a['decryption-nonce']) }, key, bytes)); + } + if (a.ox) { + const digest = bytesToHex(new Uint8Array(await crypto.subtle.digest('SHA-256', bytes))); + if (digest !== a.ox.toLowerCase()) throw new Error('hash mismatch'); + } + const blob = new Blob([bytes], { type: a.m || 'application/octet-stream' }); + Object.assign(entry, { state: 'ready', blob, src: URL.createObjectURL(blob) }); + } catch (e) { + entry.state = 'error'; + console.warn('attachment:', a.url, e.message); + } + scheduleRepaint(); + } + // The nodes for a rumor's attachments: a picture inline (tap to view), + // any other file as a download by name, a grey box the picture's shape + // while it loads, and a quiet note when it can't be had. + function attachmentNodes(rumor) { + return attachmentsOf(rumor).map((a) => { + const isImg = /^image\//i.test(a.m || '') || /\.(png|jpe?g|gif|webp|avif)$/i.test(a.name || a.url.split('?')[0]); + const encrypted = !!a['encryption-algorithm']; + if (!encrypted && isImg) return urlNode(a.url, { isImage: true }); + let entry = attachCache.get(a.url); + if (!entry && isImg) { loadAttachment(a); entry = attachCache.get(a.url); } + const [w, hgt] = String(a.dim || '').split('x').map(Number); + const ratio = w > 0 && hgt > 0 ? `${w}/${hgt}` : '4/3'; + if (entry && entry.state === 'ready') { + if (isImg) return h('img', { + src: entry.src, class: 'note-img clickable', alt: a.name || '', + onClick: (e) => { e.stopPropagation(); ctx.openImage && ctx.openImage(entry.src); }, + }); + return h('a', { class: 'chat-attach', href: entry.src, download: a.name || 'file', onClick: (e) => e.stopPropagation() }, + '๐ ' + (a.name || 'file') + (a.size ? ` ยท ${Math.round(+a.size / 1024)} KB` : '')); + } + if (entry && entry.state === 'error') return h('div', { class: 'small muted' }, t('msgAttachFailed')); + if (!isImg) return h('button', { + class: 'chat-attach linklike', onClick: (e) => { e.stopPropagation(); if (!attachCache.has(a.url)) loadAttachment(a); }, + }, '๐ ' + (a.name || 'file') + (a.size ? ` ยท ${Math.round(+a.size / 1024)} KB` : '')); + return h('div', { class: 'chat-attach-ph', style: `aspect-ratio:${ratio}` }); + }); + } + function noteBody(text, depth = 0) { const out = []; for (const part of String(text || '').split(NOTE_SPLIT)) { @@ -5026,6 +5110,7 @@ export function messagesFeature(ctx) { }, replyQuote(room, chId, m), ...noteBody(text), + ...attachmentNodes(m.rumor), edit ? h('span', { class: 'chat-edited' }, ' ', t('msgEdited')) : null, mine ? h('button', { class: 'chat-del', title: t('msgDelete'), onClick: () => deleteMessage(room, chId, m) }, 'ร') @@ -5298,7 +5383,7 @@ export function messagesFeature(ctx) { ui.msgSheet = ui.msgSheet === m.rumor.id ? null : m.rumor.id; render(); }, - }, dmQuote(m), ...noteBody(m.rumor.content), dmChips(m)), + }, dmQuote(m), ...noteBody(m.rumor.content), ...attachmentNodes(m.rumor), dmChips(m)), h('div', { class: 'chat-time' }, timeLabel(m.rumor.created_at * 1000))))) : [h('div', { class: 'muted small', style: 'text-align:center;padding:24px 0' }, t('msgNoDmsYet'))])), dmReplyBar(), |