updates readme and removes restriction on content size

Cargo.toml

@@ -24,7 +24,7 @@ license = "AGPL-3.0-only"
 name = "ordinal_crypto"
 readme = "README.md"
 repository = "https://github.com/ordinarylabs/ordinal-crypto"
-version = "0.6.2"
+version = "0.6.3"
 
 [dependencies]
 base64 = "0.21.2"
@@ -39,4 +39,4 @@ criterion = { version = "0.4", features = ["html_reports"] }
 
 [[bench]]
 name = "lib"
-harness = false
+harness = false

README.md

@@ -14,8 +14,7 @@ The cryptography library for the Ordinal Platform
 let (priv_key, pub_key) = ordinal_crypto::generate_exchange_keys();
 let (fingerprint, verifying_key) = ordinal_crypto::signature::generate_fingerprint();
 
-// MAX content size: 74.840698 mb
-let content = vec![0u8; 1214];
+let content = vec![0u8; 1215];
 
 // MAX pub keys: 65,535
 let pub_keys = vec![pub_key];
@@ -38,62 +37,14 @@ let decrypted_content = ordinal_crypto::content::decrypt(
 assert_eq!(decrypted_content, content);
 ```
 
-## Limits
+## Format
 
-- MAX public keys -> 65,535
-- MAX content size -> 74.840698 mb
-
-### Reasoning
-
-IPv6 minimum MTU 1,280 bytes
-
-each UDP packet in our system needs:
-- IPv6 headers (40 bytes)
-- UDP headers (8 bytes)
-- uuid (16 bytes)
-- position (2 bytes)
-
-our base, usable packet size, is 1,214 bytes (1,280 bytes - 40 bytes - 8 bytes - 16 bytes - 2 bytes)
-
-*total possible in a “payload” with a 16 bit position counter is 79.55949 mb (1,214 bytes * 65,535)*
-
-Encryption Components:
-- inner signature = 64 bytes
+- keys count header = 2 bytes
+- encrypted keys = 72 bytes (max is 65,535 or 4.71852 mb)
 - one-time public key = 32 bytes
-- Poly1305 MAC = 16 bytes
 - nonce = 24 bytes
-- keys count header = 2 bytes
-- **MAX public keys (encrypted keys = 72 bytes * 65,535) = 4.71852 mb**
-
-*remaining "payload" space is 74.840832 mb*
-
-Destination Components:
-- location = 16 bytes
-- PUT key = 16 bytes
-- TTL
-    - unit = 1 byte
-    - duration = 1 byte
-
-*remaining "payload" space is 74.840798 mb*
-
-Server Authentication Components:
-- payload signature = 64 bytes
-- token
-    - HMAC = 32 bytes
-    - id = 16 bytes
-    - exp = 8 bytes
-    - verifying key = 32 bytes
-    - capacity units = 1 byte
-    - write ops per CU = 2 bytes
-    - write bytes per CU = 4 bytes
-    - TTL cost multiplier
-        - hour = 1 byte
-        - day = 1 byte
-        - month = 1 byte
-        - year = 1 byte
-        - infinite = 1 byte
-
-**MAX content size is 74.840698 mb**
+- inner signature = 64 bytes (encrypted along with the content to preserve deniability)
+- Poly1305 MAC = 16 bytes
 
 ## Security
 

benches/lib.rs

@@ -51,7 +51,7 @@ fn bytes_32_decode_benchmark(c: &mut Criterion) {
 
 fn aead_encrypt_benchmark(c: &mut Criterion) {
     let key = [0u8; 32];
-    let content = [0u8; 12_140];
+    let content = [0u8; 1215];
 
     c.bench_function("aead_encrypt", |b| {
         b.iter(|| {
@@ -62,7 +62,7 @@ fn aead_encrypt_benchmark(c: &mut Criterion) {
 
 fn aead_decrypt_benchmark(c: &mut Criterion) {
     let key = [0u8; 32];
-    let content = [0u8; 12_140];
+    let content = [0u8; 1215];
 
     let encrypted_content = ordinal_crypto::aead::encrypt(&key, &content).unwrap();
 
@@ -83,7 +83,7 @@ fn signature_generate_fingerprint_benchmark(c: &mut Criterion) {
 
 fn signature_sign_benchmark(c: &mut Criterion) {
     let (fingerprint, _) = ordinal_crypto::signature::generate_fingerprint();
-    let content = [0u8; 12_140];
+    let content = [0u8; 1215];
 
     c.bench_function("signature_sign", |b| {
         b.iter(|| {
@@ -94,7 +94,7 @@ fn signature_sign_benchmark(c: &mut Criterion) {
 
 fn signature_verify_benchmark(c: &mut Criterion) {
     let (fingerprint, verifying_key) = ordinal_crypto::signature::generate_fingerprint();
-    let content = [0u8; 12_140];
+    let content = [0u8; 1215];
 
     let signature = ordinal_crypto::signature::sign(&fingerprint, &content);
 
@@ -115,7 +115,7 @@ fn generate_exchange_keys_benchmark(c: &mut Criterion) {
 
 fn content_encrypt_benchmark(c: &mut Criterion) {
     let (fingerprint, _) = ordinal_crypto::signature::generate_fingerprint();
-    let content = vec![0u8; 12_140];
+    let content = vec![0u8; 1215];
     let (_, pub_key) = ordinal_crypto::generate_exchange_keys();
     let pub_keys = vec![pub_key];
 
@@ -128,7 +128,7 @@ fn content_encrypt_benchmark(c: &mut Criterion) {
 
 fn content_encrypt_multi_recipient_benchmark(c: &mut Criterion) {
     let (fingerprint, _) = ordinal_crypto::signature::generate_fingerprint();
-    let content = vec![0u8; 12_140];
+    let content = vec![0u8; 1215];
     let mut pub_keys = vec![];
 
     for _ in 0..5000 {
@@ -145,7 +145,7 @@ fn content_encrypt_multi_recipient_benchmark(c: &mut Criterion) {
 
 fn content_extract_components_for_key_position_benchmark(c: &mut Criterion) {
     let (fingerprint, _) = ordinal_crypto::signature::generate_fingerprint();
-    let content = vec![0u8; 12_140];
+    let content = vec![0u8; 1215];
     let mut pub_keys = vec![];
 
     for _ in 0..5000 {
@@ -166,7 +166,7 @@ fn content_extract_components_for_key_position_benchmark(c: &mut Criterion) {
 
 fn decrypt_content_benchmark(c: &mut Criterion) {
     let (fingerprint, verifying_key) = ordinal_crypto::signature::generate_fingerprint();
-    let content = vec![0u8; 12_140];
+    let content = vec![0u8; 1215];
     let (priv_key, pub_key) = ordinal_crypto::generate_exchange_keys();
 
     let pub_keys = vec![pub_key];

src/lib.rs

@@ -81,7 +81,7 @@ pub mod bytes_32 {
 ///
 /// ```rust
 /// let key = [0u8; 32];
-/// let content = vec![0u8; 1214];
+/// let content = vec![0u8; 1215];
 ///
 /// let encrypted_content = ordinal_crypto::aead::encrypt(&key, &content).unwrap();
 /// assert_eq!(encrypted_content.len(), content.len() + 40);
@@ -130,7 +130,7 @@ pub mod aead {
 /// ```rust
 /// let (fingerprint, verifying_key) = ordinal_crypto::signature::generate_fingerprint();
 ///
-/// let content = vec![0u8; 1214];
+/// let content = vec![0u8; 1215];
 ///
 /// let signature = ordinal_crypto::signature::sign(&fingerprint, &content);
 ///
@@ -198,8 +198,7 @@ pub fn generate_exchange_keys() -> ([u8; 32], [u8; 32]) {
 /// let (priv_key, pub_key) = ordinal_crypto::generate_exchange_keys();
 /// let (fingerprint, verifying_key) = ordinal_crypto::signature::generate_fingerprint();
 ///
-/// // MAX content size: 74.840698 mb
-/// let content = vec![0u8; 1214];
+/// let content = vec![0u8; 1215];
 ///
 /// // MAX pub keys: 65,535
 /// let pub_keys = vec![pub_key];
@@ -234,10 +233,6 @@ pub mod content {
             return Err("cannot encrypt for more than 65,535 public keys");
         }
 
-        if content.len() > 74_840_698 {
-            return Err("cannot encrypt content larger than 74.840698 mb");
-        }
-
         // generate components
         let nonce = chacha20poly1305::XChaCha20Poly1305::generate_nonce(&mut rand_core::OsRng);
         let content_key = chacha20poly1305::XChaCha20Poly1305::generate_key(&mut rand_core::OsRng);
@@ -305,9 +300,9 @@ pub mod content {
     }
 
     pub fn extract_components_for_key_position(
-        encrypted_content: &[u8],
+        encrypted_content: &Vec<u8>,
         position: u16,
-    ) -> Result<(Vec<u8>, [u8; ENCRYPTED_KEY_LENGTH]), &'static str> {
+    ) -> Result<(&[u8], [u8; ENCRYPTED_KEY_LENGTH]), &'static str> {
         let key_header_bytes: [u8; 2] = match encrypted_content[0..2].try_into() {
             Ok(b) => b,
             Err(_) => return Err("failed to convert keys header to bytes"),
@@ -324,10 +319,7 @@ pub mod content {
             Err(_) => return Err("failed to convert content key to bytes"),
         };
 
-        Ok((
-            encrypted_content[keys_end..].to_vec(),
-            encrypted_content_key,
-        ))
+        Ok((&encrypted_content[keys_end..], encrypted_content_key))
     }
 
     pub fn decrypt(