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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/rust/origin-trial-token/lib.rs
parentInitial commit. (diff)
downloadfirefox-esr-upstream.tar.xz
firefox-esr-upstream.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/origin-trial-token/lib.rs')
-rw-r--r--third_party/rust/origin-trial-token/lib.rs268
1 files changed, 268 insertions, 0 deletions
diff --git a/third_party/rust/origin-trial-token/lib.rs b/third_party/rust/origin-trial-token/lib.rs
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+++ b/third_party/rust/origin-trial-token/lib.rs
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Implements a simple processor for
+//! https://github.com/chromium/chromium/blob/d7da0240cae77824d1eda25745c4022757499131/third_party/blink/public/common/origin_trials/origin_trials_token_structure.md
+//!
+//! This crate intentionally leaves the cryptography to the caller. See the
+//! tools/ directory for example usages.
+
+
+/// Latest version as documented.
+pub const LATEST_VERSION: u8 = 3;
+
+#[repr(C)]
+pub struct RawToken {
+ version: u8,
+ signature: [u8; 64],
+ payload_length: [u8; 4],
+ /// Payload is an slice of payload_length bytes, and has to be verified
+ /// before returning it to the caller.
+ payload: [u8; 0],
+}
+
+#[derive(Debug)]
+pub enum TokenValidationError {
+ BufferTooSmall,
+ MismatchedPayloadSize { expected: usize, actual: usize },
+ InvalidSignature,
+ UnknownVersion,
+ UnsupportedThirdPartyToken,
+ UnexpectedUsageInNonThirdPartyToken,
+ MalformedPayload(serde_json::Error),
+}
+
+impl RawToken {
+ const HEADER_SIZE: usize = std::mem::size_of::<Self>();
+
+ #[inline]
+ pub fn version(&self) -> u8 {
+ self.version
+ }
+
+ #[inline]
+ pub fn signature(&self) -> &[u8; 64] {
+ &self.signature
+ }
+
+ #[inline]
+ pub fn payload_length(&self) -> usize {
+ u32::from_be_bytes(self.payload_length) as usize
+ }
+
+ #[inline]
+ pub fn as_buffer(&self) -> &[u8] {
+ let buffer_size = Self::HEADER_SIZE + self.payload_length();
+ unsafe { std::slice::from_raw_parts(self as *const _ as *const u8, buffer_size) }
+ }
+
+ #[inline]
+ pub fn payload(&self) -> &[u8] {
+ let len = self.payload_length();
+ unsafe { std::slice::from_raw_parts(self.payload.as_ptr(), len) }
+ }
+
+ /// Returns a RawToken from a raw buffer.
+ pub fn from_buffer<'a>(buffer: &'a [u8]) -> Result<&'a Self, TokenValidationError> {
+ if buffer.len() <= Self::HEADER_SIZE {
+ return Err(TokenValidationError::BufferTooSmall);
+ }
+ assert_eq!(
+ std::mem::align_of::<Self>(),
+ 1,
+ "RawToken is a view over the buffer"
+ );
+ let raw_token = unsafe { &*(buffer.as_ptr() as *const Self) };
+ let payload = &buffer[Self::HEADER_SIZE..];
+ let expected = raw_token.payload_length();
+ let actual = payload.len();
+ if expected != actual {
+ return Err(TokenValidationError::MismatchedPayloadSize { expected, actual });
+ }
+ Ok(raw_token)
+ }
+
+ /// The data to verify the signature in this raw token.
+ fn signature_data(&self) -> Vec<u8> {
+ Self::raw_signature_data(self.version, self.payload())
+ }
+
+ /// The data to sign or verify given a payload and a version.
+ fn raw_signature_data(version: u8, payload: &[u8]) -> Vec<u8> {
+ let mut data = Vec::with_capacity(payload.len() + 5);
+ data.push(version);
+ data.extend((payload.len() as u32).to_be_bytes());
+ data.extend(payload);
+ data
+ }
+
+ /// Verify the signature of this raw token.
+ pub fn verify(&self, verify_signature: impl FnOnce(&[u8; 64], &[u8]) -> bool) -> bool {
+ let signature_data = self.signature_data();
+ verify_signature(&self.signature, &signature_data)
+ }
+}
+
+#[derive(serde::Deserialize, serde::Serialize, Debug, Eq, PartialEq)]
+#[serde(rename_all = "camelCase")]
+pub enum Usage {
+ #[serde(rename = "")]
+ None,
+ Subset,
+}
+
+impl Usage {
+ fn is_none(&self) -> bool {
+ *self == Self::None
+ }
+}
+
+impl Default for Usage {
+ fn default() -> Self {
+ Self::None
+ }
+}
+
+fn is_false(t: &bool) -> bool {
+ *t == false
+}
+
+/// An already decoded and maybe-verified token.
+#[derive(serde::Deserialize, serde::Serialize, Debug, Eq, PartialEq)]
+#[serde(rename_all = "camelCase")]
+pub struct Token {
+ pub origin: String,
+ pub feature: String,
+ pub expiry: u64, // Timestamp. Seconds since epoch.
+ #[serde(default, skip_serializing_if = "is_false")]
+ pub is_subdomain: bool,
+ #[serde(default, skip_serializing_if = "is_false")]
+ pub is_third_party: bool,
+ #[serde(default, skip_serializing_if = "Usage::is_none")]
+ pub usage: Usage,
+}
+
+impl Token {
+ #[inline]
+ pub fn origin(&self) -> &str {
+ &self.origin
+ }
+
+ #[inline]
+ pub fn feature(&self) -> &str {
+ &self.feature
+ }
+
+ #[inline]
+ pub fn expiry_since_unix_epoch(&self) -> std::time::Duration {
+ std::time::Duration::from_secs(self.expiry)
+ }
+
+ #[inline]
+ pub fn expiry_time(&self) -> Option<std::time::SystemTime> {
+ std::time::UNIX_EPOCH.checked_add(self.expiry_since_unix_epoch())
+ }
+
+ #[inline]
+ pub fn is_expired(&self) -> bool {
+ let now_duration = std::time::SystemTime::now()
+ .duration_since(std::time::UNIX_EPOCH)
+ .expect("System time before epoch?");
+ now_duration >= self.expiry_since_unix_epoch()
+ }
+
+ /// Most high-level function: For a given buffer, tries to parse it and
+ /// verify it as a token.
+ pub fn from_buffer(
+ buffer: &[u8],
+ verify_signature: impl FnOnce(&[u8; 64], &[u8]) -> bool,
+ ) -> Result<Self, TokenValidationError> {
+ Self::from_raw_token(RawToken::from_buffer(buffer)?, verify_signature)
+ }
+
+ /// Validates a RawToken's signature and converts the token if valid.
+ pub fn from_raw_token(
+ token: &RawToken,
+ verify_signature: impl FnOnce(&[u8; 64], &[u8]) -> bool,
+ ) -> Result<Self, TokenValidationError> {
+ if !token.verify(verify_signature) {
+ return Err(TokenValidationError::InvalidSignature);
+ }
+ Self::from_raw_token_unverified(token)
+ }
+
+ /// Converts the token from a raw token, without verifying first.
+ pub fn from_raw_token_unverified(token: &RawToken) -> Result<Self, TokenValidationError> {
+ Self::from_payload(token.version, token.payload())
+ }
+
+ /// Converts the token from a raw payload, version pair.
+ pub fn from_payload(version: u8, payload: &[u8]) -> Result<Self, TokenValidationError> {
+ if version != 2 && version != 3 {
+ assert_ne!(version, LATEST_VERSION);
+ return Err(TokenValidationError::UnknownVersion);
+ }
+
+ let token: Token = match serde_json::from_slice(payload) {
+ Ok(t) => t,
+ Err(e) => return Err(TokenValidationError::MalformedPayload(e)),
+ };
+
+ // Third-party tokens are not supported in version 2.
+ if token.is_third_party {
+ if version == 2 {
+ return Err(TokenValidationError::UnsupportedThirdPartyToken);
+ }
+ } else if !token.usage.is_none() {
+ return Err(TokenValidationError::UnexpectedUsageInNonThirdPartyToken);
+ }
+
+ Ok(token)
+ }
+
+ /// Converts the token to a raw payload.
+ pub fn to_payload(&self) -> Vec<u8> {
+ serde_json::to_string(self)
+ .expect("Should always be able to turn a token into a payload")
+ .into_bytes()
+ }
+
+ /// Converts the token to the data that should be signed.
+ pub fn to_signature_data(&self) -> Vec<u8> {
+ RawToken::raw_signature_data(LATEST_VERSION, &self.to_payload())
+ }
+
+ /// Turns the token into a fully signed token.
+ pub fn to_signed_token(&self, sign: impl FnOnce(&[u8]) -> [u8; 64]) -> Vec<u8> {
+ self.to_signed_token_with_payload(sign, &self.to_payload())
+ }
+
+ /// DO NOT EXPOSE: This is intended for testing only. We need to test with
+ /// the original payload so that the tokens match, but we assert
+ /// that self.to_payload() and payload are equivalent.
+ fn to_signed_token_with_payload(
+ &self,
+ sign: impl FnOnce(&[u8]) -> [u8; 64],
+ payload: &[u8],
+ ) -> Vec<u8> {
+ let signature_data_with_payload = RawToken::raw_signature_data(LATEST_VERSION, &payload);
+ let signature = sign(&signature_data_with_payload);
+
+ let mut buffer = Vec::with_capacity(1 + signature.len() + 4 + payload.len());
+ buffer.push(LATEST_VERSION);
+ buffer.extend(signature);
+ buffer.extend((payload.len() as u32).to_be_bytes());
+ buffer.extend(payload);
+
+ if cfg!(debug_assertions) {
+ let token = Self::from_buffer(&buffer, |_, _| true).expect("Creating malformed token?");
+ assert_eq!(self, &token, "Token differs after deserialization?");
+ }
+
+ buffer
+ }
+}
+
+#[cfg(test)]
+mod tests;