Struct Tag

pub struct Tag<const GAMMA: u8> { /* private fields */ }

A tag is a probabilistic cryptographic structure. When constructed for a given TaggingKey it will pass the DetectionKey::test_tag 100% of the time. For other tagging keys it will pass the test with probability GAMMA related to the security parameter of the system. This system provides the following security properties:

• Correctness: Valid tags constructed for a specific tagging key will always validate when tested using the detection key
• Fuzziness: Invalid tags will produce false positives with probability p related to the security property (γ)
• Security: An adversarial server with access to the detection key is unable to distinguish false positives from true positives. (Detection Ambiguity)

Implementations

impl<const GAMMA: u8> Tag<GAMMA>

pub fn compress(&self) -> Vec<u8>

An optimal sized copy of the tag Compressed u || y || ciphertext Ciphertext is right-padded with zeros to the nearest byte You probably want to use one of the many serde serialize apis instead (see README)

   use rand::rngs::OsRng;
   use fuzzytags::RootSecret;
   let mut rng = OsRng;
   let secret = RootSecret::<24>::generate(&mut rng);
   let tagging_key = secret.tagging_key();
   // extract a detection key
   let detection_key = secret.extract_detection_key(5);

   // Give tagging key to a another party...
   // and then they can do...
   let tag = tagging_key.generate_tag(&mut rng);
   let compressed_tag = tag.compress();

pub fn decompress(bytes: &[u8]) -> Option<Tag<GAMMA>>

decompress an optimally encoded fuzzytag byte array, returns None if invalid You probably want to use one of the many serde deserialize apis instead (see README)

   use fuzzytags::{RootSecret, Tag};
   use rand::rngs::OsRng;
   let mut rng = OsRng;
   let secret = RootSecret::<24>::generate(&mut rng);
   let tagging_key = secret.tagging_key();
   // extract a detection key
   let detection_key = secret.extract_detection_key(5);

   // Give tagging key to a another party...
   // and then they can do...
   let tag = tagging_key.generate_tag(&mut rng);
   let compressed_tag = tag.compress();
   let decompressed_tag = Tag::decompress(&compressed_tag).unwrap();
   assert_eq!(tag, decompressed_tag);

Trait Implementations

impl<const GAMMA: u8> Clone for Tag<GAMMA>

fn clone(&self) -> Tag<GAMMA>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<const GAMMA: u8> Debug for Tag<GAMMA>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de, const GAMMA: u8> Deserialize<'de> for Tag<GAMMA>

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<const GAMMA: u8> Display for Tag<GAMMA>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<const GAMMA: u8> PartialEq for Tag<GAMMA>

fn eq(&self, other: &Tag<GAMMA>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<const GAMMA: u8> Serialize for Tag<GAMMA>

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl<const GAMMA: u8> Eq for Tag<GAMMA>

impl<const GAMMA: u8> StructuralPartialEq for Tag<GAMMA>