Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

avoid nonce reuse for large payloads #11

Merged
merged 2 commits into from Feb 8, 2023
Merged

avoid nonce reuse for large payloads #11

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
843389a
avoid nonce reuse for large payloads
CluEleSsUK Dec 20, 2022
59bcd64
fixed counter bound
CluEleSsUK Jan 24, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
8 changes: 8 additions & 0 deletions src/age/stream-cipher.ts
View file
Open in desktop
Expand Up @@ -12,6 +12,10 @@ const TAG_SIZE = 16 // Poly1305 MAC size
const ENCRYPTED_CHUNK_SIZE = CHUNK_SIZE + TAG_SIZE
const NONCE_SIZE = 12 // STREAM nonce size

// due to using a 32bit uint for the counter, this is the max
// value the counter can be without risking a nonce reuse
const COUNTER_MAX = Math.pow(2, 32) - 1

type ui8a = Uint8Array

export class STREAM {
Expand Down Expand Up @@ -85,6 +89,10 @@ export class STREAM {
// Increments Big Endian Uint8Array-based counter.
// [0, 0, 0] => [0, 0, 1] ... => [0, 0, 255] => [0, 1, 0]
incrementCounter() {
if (this.counter == COUNTER_MAX) {
throw new Error("Stream cipher counter has already hit max value! Aborting to avoid nonce reuse - tlock only supports payloads up to 256TB")
}

this.counter += 1
this.nonceView.setUint32(7, this.counter, false)
}
Expand Down