From 1bf8c5f3f08e75276fa812cb248c6eda5cd3beae Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Wed, 19 Jun 2024 20:59:56 +1200
Subject: [PATCH 01/29] dev snip52 toolkit

---
 Cargo.toml                           |  3 +-
 packages/notification/Cargo.toml     | 34 +++++++++++
 packages/notification/Readme.md      |  5 ++
 packages/notification/src/crypto.rs  | 59 +++++++++++++++++++
 packages/notification/src/funcs.rs   | 84 ++++++++++++++++++++++++++++
 packages/notification/src/lib.rs     |  8 +++
 packages/notification/src/structs.rs | 70 +++++++++++++++++++++++
 src/lib.rs                           |  2 +
 8 files changed, 264 insertions(+), 1 deletion(-)
 create mode 100644 packages/notification/Cargo.toml
 create mode 100644 packages/notification/Readme.md
 create mode 100644 packages/notification/src/crypto.rs
 create mode 100644 packages/notification/src/funcs.rs
 create mode 100644 packages/notification/src/lib.rs
 create mode 100644 packages/notification/src/structs.rs

diff --git a/Cargo.toml b/Cargo.toml
index bb94dc0..18e35c2 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,6 +34,7 @@ snip721 = ["secret-toolkit-snip721", "utils"]
 storage = ["secret-toolkit-storage", "serialization"]
 utils = ["secret-toolkit-utils"]
 viewing-key = ["secret-toolkit-viewing-key"]
+notification = ["secret-toolkit-notification"]
 
 [dependencies]
 secret-toolkit-crypto = { version = "0.10.0", path = "packages/crypto", optional = true }
@@ -45,7 +46,7 @@ secret-toolkit-snip721 = { version = "0.10.0", path = "packages/snip721", option
 secret-toolkit-storage = { version = "0.10.0", path = "packages/storage", optional = true }
 secret-toolkit-utils = { version = "0.10.0", path = "packages/utils", optional = true }
 secret-toolkit-viewing-key = { version = "0.10.0", path = "packages/viewing_key", optional = true }
-
+secret-toolkit-notification = { version = "0.10.0", path = "packages/notification", optional = true }
 
 [workspace]
 members = ["packages/*"]
diff --git a/packages/notification/Cargo.toml b/packages/notification/Cargo.toml
new file mode 100644
index 0000000..1203ccd
--- /dev/null
+++ b/packages/notification/Cargo.toml
@@ -0,0 +1,34 @@
+[package]
+name = "secret-toolkit-notification"
+version = "0.10.0"
+edition = "2021"
+authors = ["darwinzer0","blake-regalia"]
+license-file = "../../LICENSE"
+repository = "https://github.com/scrtlabs/secret-toolkit"
+readme = "Readme.md"
+description = "Helper tools for SNIP-52 notifications in Secret Contracts"
+categories = ["cryptography::cryptocurrencies", "wasm"]
+keywords = ["secret-network", "secret-contracts", "secret-toolkit"]
+
+[package.metadata.docs.rs]
+all-features = true
+
+[dependencies]
+cosmwasm-std = { workspace = true, version = "1.0.0" }
+serde = { workspace = true }
+
+ripemd = { version = "0.1.3", default-features = false }
+schemars = { workspace = true }
+
+minicbor-ser = "0.2.0"
+# rand_core = { version = "0.6.4", default-features = false }
+# rand_chacha = { version = "0.3.1", default-features = false }
+sha2 = "0.10.6"
+hkdf = "0.12.3"
+chacha20poly1305 = { version = "0.10.1", default-features = false, features = ["alloc", "rand_core"] }
+generic-array = "0.14.7"
+primitive-types = { version = "0.12.2", default-features = false }
+
+secret-toolkit-crypto = { version = "0.10.0", path = "../crypto", features = [
+    "hash",
+] }
\ No newline at end of file
diff --git a/packages/notification/Readme.md b/packages/notification/Readme.md
new file mode 100644
index 0000000..85955e8
--- /dev/null
+++ b/packages/notification/Readme.md
@@ -0,0 +1,5 @@
+# Secret Contract Development Toolkit - SNIP52 (Private Push Notification) Interface
+
+⚠️ This package is a sub-package of the `secret-toolkit` package. Please see its crate page for more context.
+
+These functions are meant to help you easily create notification channels for private push notifications in secret contracts. [SNIP-52 Private Push Notification](https://github.com/SolarRepublic/SNIPs/blob/feat/snip-52/SNIP-52.md)
\ No newline at end of file
diff --git a/packages/notification/src/crypto.rs b/packages/notification/src/crypto.rs
new file mode 100644
index 0000000..2e54ef7
--- /dev/null
+++ b/packages/notification/src/crypto.rs
@@ -0,0 +1,59 @@
+use chacha20poly1305::{
+    aead::{AeadInPlace, KeyInit},
+    ChaCha20Poly1305,
+};
+use cosmwasm_std::{StdError, StdResult};
+use generic_array::GenericArray;
+use hkdf::{hmac::Hmac, Hkdf};
+use sha2::{Sha256, Sha512};
+
+// Create alias for HMAC-SHA256
+pub type HmacSha256 = Hmac<Sha256>;
+
+pub fn cipher_data(key: &[u8], nonce: &[u8], plaintext: &[u8], aad: &[u8]) -> StdResult<Vec<u8>> {
+    let cipher = ChaCha20Poly1305::new_from_slice(key)
+        .map_err(|e| StdError::generic_err(format!("{:?}", e)))?;
+    let mut buffer: Vec<u8> = plaintext.to_vec();
+    cipher
+        .encrypt_in_place(GenericArray::from_slice(nonce), aad, &mut buffer)
+        .map_err(|e| StdError::generic_err(format!("{:?}", e)))?;
+    Ok(buffer)
+}
+
+pub fn hkdf_sha_256(
+    salt: &Option<Vec<u8>>,
+    ikm: &[u8],
+    info: &[u8],
+    length: usize,
+) -> StdResult<Vec<u8>> {
+    let hk: Hkdf<Sha256> = Hkdf::<Sha256>::new(salt.as_deref().map(|s| s), ikm);
+    let mut zero_bytes = vec![0u8; length];
+    let mut okm = zero_bytes.as_mut_slice();
+    match hk.expand(info, &mut okm) {
+        Ok(_) => Ok(okm.to_vec()),
+        Err(e) => {
+            return Err(StdError::generic_err(format!("{:?}", e)));
+        }
+    }
+}
+
+pub fn hkdf_sha_512(
+    salt: &Option<Vec<u8>>,
+    ikm: &[u8],
+    info: &[u8],
+    length: usize,
+) -> StdResult<Vec<u8>> {
+    let hk: Hkdf<Sha512> = Hkdf::<Sha512>::new(salt.as_deref().map(|s| s), ikm);
+    let mut zero_bytes = vec![0u8; length];
+    let mut okm = zero_bytes.as_mut_slice();
+    match hk.expand(info, &mut okm) {
+        Ok(_) => Ok(okm.to_vec()),
+        Err(e) => {
+            return Err(StdError::generic_err(format!("{:?}", e)));
+        }
+    }
+}
+
+pub fn xor_bytes(vec1: &[u8], vec2: &[u8]) -> Vec<u8> {
+    vec1.iter().zip(vec2.iter()).map(|(&a, &b)| a ^ b).collect()
+}
diff --git a/packages/notification/src/funcs.rs b/packages/notification/src/funcs.rs
new file mode 100644
index 0000000..8ff997b
--- /dev/null
+++ b/packages/notification/src/funcs.rs
@@ -0,0 +1,84 @@
+use cosmwasm_std::{Binary, CanonicalAddr, StdResult};
+use secret_toolkit_crypto::sha_256;
+use hkdf::hmac::Mac;
+use crate::{cipher_data, hkdf_sha_256, HmacSha256};
+
+pub const NOTIFICATION_BLOCK_SIZE: usize = 36;
+pub const SEED_LEN: usize = 32;
+
+///
+/// fn notification_id
+///
+///   Returns a notification id for the given address and channel id.
+///
+pub fn notification_id(seed: &Binary, channel: &str, tx_hash: &String) -> StdResult<Binary> {
+    // compute notification ID for this event
+    let material = [channel.as_bytes(), ":".as_bytes(), tx_hash.as_bytes()].concat();
+
+    let mut mac: HmacSha256 = HmacSha256::new_from_slice(seed.0.as_slice()).unwrap();
+    mac.update(material.as_slice());
+    let result = mac.finalize();
+    let code_bytes = result.into_bytes();
+    Ok(Binary::from(code_bytes.as_slice()))
+}
+
+///
+/// fn encrypt_notification_data
+///
+///   Returns encrypted bytes given plaintext bytes, address, and channel id.
+///
+pub fn encrypt_notification_data(
+    block_height: &u64,
+    tx_hash: &String,
+    seed: &Binary,
+    channel: &str,
+    plaintext: Vec<u8>,
+) -> StdResult<Binary> {
+    let mut padded_plaintext = plaintext.clone();
+    zero_pad(&mut padded_plaintext, NOTIFICATION_BLOCK_SIZE);
+
+    let channel_id_bytes = sha_256(channel.as_bytes())[..12].to_vec();
+    let salt_bytes = tx_hash.as_bytes()[..12].to_vec();
+    let nonce: Vec<u8> = channel_id_bytes
+        .iter()
+        .zip(salt_bytes.iter())
+        .map(|(&b1, &b2)| b1 ^ b2)
+        .collect();
+    let aad = format!("{}:{}", block_height, tx_hash);
+
+    // encrypt notification data for this event
+    let tag_ciphertext = cipher_data(
+        seed.0.as_slice(),
+        nonce.as_slice(),
+        padded_plaintext.as_slice(),
+        aad.as_bytes(),
+    )?;
+
+    Ok(Binary::from(tag_ciphertext.clone()))
+}
+
+/// get the seed for a secret and given address
+pub fn get_seed(addr: &CanonicalAddr, secret: &[u8]) -> StdResult<Binary> {
+    let seed = hkdf_sha_256(
+        &None,
+        secret,
+        addr.as_slice(),
+        SEED_LEN,
+    )?;
+    Ok(Binary::from(seed))
+}
+
+/// Take a Vec<u8> and pad it up to a multiple of `block_size`, using 0x00 at the end.
+fn zero_pad(message: &mut Vec<u8>, block_size: usize) -> &mut Vec<u8> {
+    let len = message.len();
+    let surplus = len % block_size;
+    if surplus == 0 {
+        return message;
+    }
+
+    let missing = block_size - surplus;
+    message.reserve(missing);
+    message.extend(std::iter::repeat(0x00).take(missing));
+    message
+}
+
diff --git a/packages/notification/src/lib.rs b/packages/notification/src/lib.rs
new file mode 100644
index 0000000..ebc3c98
--- /dev/null
+++ b/packages/notification/src/lib.rs
@@ -0,0 +1,8 @@
+#![doc = include_str!("../Readme.md")]
+
+pub mod structs;
+pub mod funcs;
+pub mod crypto;
+pub use structs::*;
+pub use funcs::*;
+pub use crypto::*;
\ No newline at end of file
diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
new file mode 100644
index 0000000..ab55a33
--- /dev/null
+++ b/packages/notification/src/structs.rs
@@ -0,0 +1,70 @@
+use cosmwasm_std::{Addr, Api, Binary, Env, StdError, StdResult};
+use serde::{Deserialize, Serialize};
+
+use crate::{encrypt_notification_data, get_seed, notification_id};
+
+#[derive(Serialize, Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(Eq, PartialEq))]
+pub struct Notification<T: NotificationData> {
+    // target for the notification
+    pub notification_for: Addr,
+    // data
+    pub data: T,
+}
+
+impl<T: NotificationData> Notification<T> {
+    pub fn new(notification_for: Addr, data: T) -> Self {
+        Notification {
+            notification_for,
+            data,
+        }
+    }
+
+    pub fn to_txhash_notification(
+        &self,
+        api: &dyn Api,
+        env: &Env,
+        secret: &[u8],
+    ) -> StdResult<TxHashNotification> {
+        let tx_hash = env.transaction.clone().ok_or(StdError::generic_err("no tx hash found"))?.hash;
+        let notification_for_raw = api.addr_canonicalize(self.notification_for.as_str())?;
+        let seed = get_seed(&notification_for_raw, secret)?;
+
+        // get notification id
+        let id = notification_id(&seed, self.data.channel_id(), &tx_hash)?;
+
+        // use CBOR to encode the data
+        let cbor_data = self.data.to_cbor(api)?;
+
+        // encrypt the receiver message
+        let encrypted_data =
+            encrypt_notification_data(&env.block.height, &tx_hash, &seed, self.data.channel_id(), cbor_data)?;
+
+        Ok(TxHashNotification {
+            id,
+            encrypted_data,
+        })
+    }
+}
+
+pub trait NotificationData {
+    fn to_cbor(&self, api: &dyn Api) -> StdResult<Vec<u8>>;
+    fn channel_id(&self) -> &str;
+}
+
+#[derive(Serialize, Debug, Deserialize, Clone)]
+#[cfg_attr(test, derive(Eq, PartialEq))]
+pub struct TxHashNotification {
+    pub id: Binary,
+    pub encrypted_data: Binary,
+}
+
+impl TxHashNotification {
+    pub fn id_plaintext(&self) -> String {
+        format!("snip52:{}", self.id.to_base64())
+    }
+
+    pub fn data_plaintext(&self) -> String {
+        self.encrypted_data.to_base64()
+    }
+}
\ No newline at end of file
diff --git a/src/lib.rs b/src/lib.rs
index 66bf181..6e87575 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -18,3 +18,5 @@ pub use secret_toolkit_storage as storage;
 pub use secret_toolkit_utils as utils;
 #[cfg(feature = "viewing-key")]
 pub use secret_toolkit_viewing_key as viewing_key;
+#[cfg(feature = "notification")]
+pub use secret_toolkit_notification as notification;

From f4d83e7dcabf55832150a0f311b58dfbc949e82b Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Mon, 15 Jul 2024 20:02:21 +1200
Subject: [PATCH 02/29] dev: move hkdf functions to crypto package

---
 packages/crypto/Cargo.toml                    |  2 ++
 .../src/crypto.rs => crypto/src/hkdf.rs}      | 21 +------------------
 packages/crypto/src/lib.rs                    |  5 +++++
 packages/notification/Cargo.toml              |  4 ++--
 packages/notification/src/cipher.rs           | 20 ++++++++++++++++++
 packages/notification/src/funcs.rs            |  4 ++--
 packages/notification/src/lib.rs              |  4 ++--
 7 files changed, 34 insertions(+), 26 deletions(-)
 rename packages/{notification/src/crypto.rs => crypto/src/hkdf.rs} (62%)
 create mode 100644 packages/notification/src/cipher.rs

diff --git a/packages/crypto/Cargo.toml b/packages/crypto/Cargo.toml
index 4ac4312..b787d7a 100644
--- a/packages/crypto/Cargo.toml
+++ b/packages/crypto/Cargo.toml
@@ -18,6 +18,7 @@ default = ["hash", "ecc-secp256k1", "rand"]
 hash = ["sha2"]
 ecc-secp256k1 = ["secp256k1"]
 rand = ["hash", "rand_chacha", "rand_core"]
+hkdf = ["sha2"]
 
 [dependencies]
 rand_core = { version = "0.6.4", default-features = false, optional = true }
@@ -26,6 +27,7 @@ sha2 = { version = "0.10.6", default-features = false, optional = true }
 secp256k1 = { version = "0.27.0", default-features = false, features = [
     "alloc",
 ], optional = true }
+hkdf = "0.12.3"
 cosmwasm-std = { workspace = true }
 
 [dev-dependencies]
diff --git a/packages/notification/src/crypto.rs b/packages/crypto/src/hkdf.rs
similarity index 62%
rename from packages/notification/src/crypto.rs
rename to packages/crypto/src/hkdf.rs
index 2e54ef7..b733a09 100644
--- a/packages/notification/src/crypto.rs
+++ b/packages/crypto/src/hkdf.rs
@@ -1,25 +1,10 @@
-use chacha20poly1305::{
-    aead::{AeadInPlace, KeyInit},
-    ChaCha20Poly1305,
-};
 use cosmwasm_std::{StdError, StdResult};
-use generic_array::GenericArray;
 use hkdf::{hmac::Hmac, Hkdf};
 use sha2::{Sha256, Sha512};
 
 // Create alias for HMAC-SHA256
 pub type HmacSha256 = Hmac<Sha256>;
 
-pub fn cipher_data(key: &[u8], nonce: &[u8], plaintext: &[u8], aad: &[u8]) -> StdResult<Vec<u8>> {
-    let cipher = ChaCha20Poly1305::new_from_slice(key)
-        .map_err(|e| StdError::generic_err(format!("{:?}", e)))?;
-    let mut buffer: Vec<u8> = plaintext.to_vec();
-    cipher
-        .encrypt_in_place(GenericArray::from_slice(nonce), aad, &mut buffer)
-        .map_err(|e| StdError::generic_err(format!("{:?}", e)))?;
-    Ok(buffer)
-}
-
 pub fn hkdf_sha_256(
     salt: &Option<Vec<u8>>,
     ikm: &[u8],
@@ -52,8 +37,4 @@ pub fn hkdf_sha_512(
             return Err(StdError::generic_err(format!("{:?}", e)));
         }
     }
-}
-
-pub fn xor_bytes(vec1: &[u8], vec2: &[u8]) -> Vec<u8> {
-    vec1.iter().zip(vec2.iter()).map(|(&a, &b)| a ^ b).collect()
-}
+}
\ No newline at end of file
diff --git a/packages/crypto/src/lib.rs b/packages/crypto/src/lib.rs
index 5fe8308..cfbcb89 100644
--- a/packages/crypto/src/lib.rs
+++ b/packages/crypto/src/lib.rs
@@ -12,3 +12,8 @@ pub use hash::{sha_256, SHA256_HASH_SIZE};
 
 #[cfg(feature = "rand")]
 pub use rng::ContractPrng;
+
+#[cfg(feature = "hkdf")]
+pub mod hkdf;
+#[cfg(feature = "hkdf")]
+pub use crate::hkdf::*;
diff --git a/packages/notification/Cargo.toml b/packages/notification/Cargo.toml
index 1203ccd..16dc3fb 100644
--- a/packages/notification/Cargo.toml
+++ b/packages/notification/Cargo.toml
@@ -24,11 +24,11 @@ minicbor-ser = "0.2.0"
 # rand_core = { version = "0.6.4", default-features = false }
 # rand_chacha = { version = "0.3.1", default-features = false }
 sha2 = "0.10.6"
-hkdf = "0.12.3"
 chacha20poly1305 = { version = "0.10.1", default-features = false, features = ["alloc", "rand_core"] }
 generic-array = "0.14.7"
+hkdf = "0.12.3"
 primitive-types = { version = "0.12.2", default-features = false }
 
 secret-toolkit-crypto = { version = "0.10.0", path = "../crypto", features = [
-    "hash",
+    "hash", "hkdf"
 ] }
\ No newline at end of file
diff --git a/packages/notification/src/cipher.rs b/packages/notification/src/cipher.rs
new file mode 100644
index 0000000..1d42dc8
--- /dev/null
+++ b/packages/notification/src/cipher.rs
@@ -0,0 +1,20 @@
+use chacha20poly1305::{
+    aead::{AeadInPlace, KeyInit},
+    ChaCha20Poly1305,
+};
+use cosmwasm_std::{StdError, StdResult};
+use generic_array::GenericArray;
+
+pub fn cipher_data(key: &[u8], nonce: &[u8], plaintext: &[u8], aad: &[u8]) -> StdResult<Vec<u8>> {
+    let cipher = ChaCha20Poly1305::new_from_slice(key)
+        .map_err(|e| StdError::generic_err(format!("{:?}", e)))?;
+    let mut buffer: Vec<u8> = plaintext.to_vec();
+    cipher
+        .encrypt_in_place(GenericArray::from_slice(nonce), aad, &mut buffer)
+        .map_err(|e| StdError::generic_err(format!("{:?}", e)))?;
+    Ok(buffer)
+}
+
+pub fn xor_bytes(vec1: &[u8], vec2: &[u8]) -> Vec<u8> {
+    vec1.iter().zip(vec2.iter()).map(|(&a, &b)| a ^ b).collect()
+}
diff --git a/packages/notification/src/funcs.rs b/packages/notification/src/funcs.rs
index 8ff997b..cd0ef9d 100644
--- a/packages/notification/src/funcs.rs
+++ b/packages/notification/src/funcs.rs
@@ -1,7 +1,7 @@
 use cosmwasm_std::{Binary, CanonicalAddr, StdResult};
-use secret_toolkit_crypto::sha_256;
+use secret_toolkit_crypto::{sha_256, hkdf_sha_256, HmacSha256};
 use hkdf::hmac::Mac;
-use crate::{cipher_data, hkdf_sha_256, HmacSha256};
+use crate::cipher_data;
 
 pub const NOTIFICATION_BLOCK_SIZE: usize = 36;
 pub const SEED_LEN: usize = 32;
diff --git a/packages/notification/src/lib.rs b/packages/notification/src/lib.rs
index ebc3c98..3e25990 100644
--- a/packages/notification/src/lib.rs
+++ b/packages/notification/src/lib.rs
@@ -2,7 +2,7 @@
 
 pub mod structs;
 pub mod funcs;
-pub mod crypto;
+pub mod cipher;
 pub use structs::*;
 pub use funcs::*;
-pub use crypto::*;
\ No newline at end of file
+pub use cipher::*;
\ No newline at end of file

From 45ed13a4c2076764c735aac646ac09ae789a86ee Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Wed, 7 Aug 2024 21:34:57 +1200
Subject: [PATCH 03/29] dev: add parameter to override default notification
 block size

---
 packages/notification/src/funcs.rs   |  9 ++++++---
 packages/notification/src/structs.rs | 11 +++++++++--
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/packages/notification/src/funcs.rs b/packages/notification/src/funcs.rs
index cd0ef9d..2600dc1 100644
--- a/packages/notification/src/funcs.rs
+++ b/packages/notification/src/funcs.rs
@@ -3,8 +3,9 @@ use secret_toolkit_crypto::{sha_256, hkdf_sha_256, HmacSha256};
 use hkdf::hmac::Mac;
 use crate::cipher_data;
 
+/// default notification block size in bytes
 pub const NOTIFICATION_BLOCK_SIZE: usize = 36;
-pub const SEED_LEN: usize = 32;
+pub const SEED_LEN: usize = 32; // 256 bits
 
 ///
 /// fn notification_id
@@ -25,7 +26,8 @@ pub fn notification_id(seed: &Binary, channel: &str, tx_hash: &String) -> StdRes
 ///
 /// fn encrypt_notification_data
 ///
-///   Returns encrypted bytes given plaintext bytes, address, and channel id.
+///   Returns encrypted bytes given plaintext bytes, address, and channel id. 
+///   Optionally, can set block size (default 36).
 ///
 pub fn encrypt_notification_data(
     block_height: &u64,
@@ -33,9 +35,10 @@ pub fn encrypt_notification_data(
     seed: &Binary,
     channel: &str,
     plaintext: Vec<u8>,
+    block_size: Option<usize>,
 ) -> StdResult<Binary> {
     let mut padded_plaintext = plaintext.clone();
-    zero_pad(&mut padded_plaintext, NOTIFICATION_BLOCK_SIZE);
+    zero_pad(&mut padded_plaintext, block_size.unwrap_or(NOTIFICATION_BLOCK_SIZE));
 
     let channel_id_bytes = sha_256(channel.as_bytes())[..12].to_vec();
     let salt_bytes = tx_hash.as_bytes()[..12].to_vec();
diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index ab55a33..fbacf47 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -25,6 +25,7 @@ impl<T: NotificationData> Notification<T> {
         api: &dyn Api,
         env: &Env,
         secret: &[u8],
+        block_size: Option<usize>,
     ) -> StdResult<TxHashNotification> {
         let tx_hash = env.transaction.clone().ok_or(StdError::generic_err("no tx hash found"))?.hash;
         let notification_for_raw = api.addr_canonicalize(self.notification_for.as_str())?;
@@ -37,8 +38,14 @@ impl<T: NotificationData> Notification<T> {
         let cbor_data = self.data.to_cbor(api)?;
 
         // encrypt the receiver message
-        let encrypted_data =
-            encrypt_notification_data(&env.block.height, &tx_hash, &seed, self.data.channel_id(), cbor_data)?;
+        let encrypted_data = encrypt_notification_data(
+            &env.block.height,
+            &tx_hash,
+            &seed,
+            self.data.channel_id(),
+            cbor_data,
+            block_size,
+        )?;
 
         Ok(TxHashNotification {
             id,

From 8fdfeef7d55e917fdd46da48aa1fae4b64402935 Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Wed, 7 Aug 2024 22:15:07 +1200
Subject: [PATCH 04/29] doc: instructions in README

---
 packages/notification/Readme.md | 58 ++++++++++++++++++++++++++++++++-
 1 file changed, 57 insertions(+), 1 deletion(-)

diff --git a/packages/notification/Readme.md b/packages/notification/Readme.md
index 85955e8..e1c9901 100644
--- a/packages/notification/Readme.md
+++ b/packages/notification/Readme.md
@@ -2,4 +2,60 @@
 
 ⚠️ This package is a sub-package of the `secret-toolkit` package. Please see its crate page for more context.
 
-These functions are meant to help you easily create notification channels for private push notifications in secret contracts. [SNIP-52 Private Push Notification](https://github.com/SolarRepublic/SNIPs/blob/feat/snip-52/SNIP-52.md)
\ No newline at end of file
+These functions are meant to help you easily create notification channels for private push notifications in secret contracts. [SNIP-52 Private Push Notification](https://github.com/SolarRepublic/SNIPs/blob/feat/snip-52/SNIP-52.md)
+
+### Implementing a `NotificationData` struct
+
+Each notification channel will have a specified data format, which is defined by defining a struct that implements the `NotificationData` trait that has two methods: `to_cbor` and `channel_id`. The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `address` and `amount`.
+
+```rust
+#[derive(Serialize, Debug, Deserialize, Clone)]
+pub struct MyNotificationData {
+    pub message: String,
+    pub amount: u128,
+}
+
+impl NotificationData for MyNotificationData {
+    fn to_cbor(&self, _api: &dyn Api) -> StdResult<Vec<u8>> {
+        let my_data = cbor::to_vec(&(
+            self.message.as_bytes(),
+            self.amount.to_be_bytes(),
+        ))
+        .map_err(|e| StdError::generic_err(format!("{:?}", e)))?;
+
+        Ok(my_data)
+    }
+
+    fn channel_id(&self) -> &str {
+        "my_channel"
+    }
+}
+```
+
+The `api` parameter for `to_cbor` is not used in this example, but is there for cases where you might want to convert an `Addr` to a `CanonicalAddr` before encoding using CBOR.
+
+### Sending a TxHash notification
+
+To send a notification to a recipient you then create a new `Notification` passing in the address of the recipient along with the notification data you want to send. The following creates a notification for the above `my_channel` and adds it to the contract `Response` as a plaintext attribute.
+
+```rust
+let note = Notification::new(
+    recipient,
+    MyNotificationData {
+        "hello".to_string(),
+        1000_u128,
+    }
+);
+
+// ... other code
+
+// add notification to response
+Ok(Response::new()
+    .set_data(to_binary(&ExecuteAnswer::MyMessage { status: Success } )?)
+    .add_attribute_plaintext(
+        note.id_plaintext(),
+        note.data_plaintext(),
+    )
+)
+```
+

From de841c1100859abc5659c4dffe96ddebc2d665ab Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Wed, 7 Aug 2024 22:17:55 +1200
Subject: [PATCH 05/29] doc: minor edit

---
 packages/notification/Readme.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/notification/Readme.md b/packages/notification/Readme.md
index e1c9901..3970d7b 100644
--- a/packages/notification/Readme.md
+++ b/packages/notification/Readme.md
@@ -2,7 +2,7 @@
 
 ⚠️ This package is a sub-package of the `secret-toolkit` package. Please see its crate page for more context.
 
-These functions are meant to help you easily create notification channels for private push notifications in secret contracts. [SNIP-52 Private Push Notification](https://github.com/SolarRepublic/SNIPs/blob/feat/snip-52/SNIP-52.md)
+These functions are meant to help you easily create notification channels for private push notifications in secret contracts (see [SNIP-52 Private Push Notification](https://github.com/SolarRepublic/SNIPs/blob/feat/snip-52/SNIP-52.md)).
 
 ### Implementing a `NotificationData` struct
 

From dfb5236587432347e36ec331feb54f0289c87350 Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Wed, 7 Aug 2024 22:18:29 +1200
Subject: [PATCH 06/29] doc: minor edit

---
 packages/notification/Readme.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/notification/Readme.md b/packages/notification/Readme.md
index 3970d7b..43412ee 100644
--- a/packages/notification/Readme.md
+++ b/packages/notification/Readme.md
@@ -6,7 +6,7 @@ These functions are meant to help you easily create notification channels for pr
 
 ### Implementing a `NotificationData` struct
 
-Each notification channel will have a specified data format, which is defined by defining a struct that implements the `NotificationData` trait that has two methods: `to_cbor` and `channel_id`. The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `address` and `amount`.
+Each notification channel will have a specified data format, which is defined by creating a struct that implements the `NotificationData` trait that has two methods: `to_cbor` and `channel_id`. The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `address` and `amount`.
 
 ```rust
 #[derive(Serialize, Debug, Deserialize, Clone)]

From 4413ffecc130a589875afae6705ecd43d23e395e Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Wed, 7 Aug 2024 22:19:30 +1200
Subject: [PATCH 07/29] doc: fix typo

---
 packages/notification/Readme.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/notification/Readme.md b/packages/notification/Readme.md
index 43412ee..bc19b95 100644
--- a/packages/notification/Readme.md
+++ b/packages/notification/Readme.md
@@ -6,7 +6,7 @@ These functions are meant to help you easily create notification channels for pr
 
 ### Implementing a `NotificationData` struct
 
-Each notification channel will have a specified data format, which is defined by creating a struct that implements the `NotificationData` trait that has two methods: `to_cbor` and `channel_id`. The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `address` and `amount`.
+Each notification channel will have a specified data format, which is defined by creating a struct that implements the `NotificationData` trait, which has two methods: `to_cbor` and `channel_id`. The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `message` and `amount`.
 
 ```rust
 #[derive(Serialize, Debug, Deserialize, Clone)]

From d18cf7e58e83dd83b958216d3cdd25c762cb99d9 Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Thu, 8 Aug 2024 15:50:21 +1200
Subject: [PATCH 08/29] docs: txhash notification example

---
 packages/notification/Readme.md | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/packages/notification/Readme.md b/packages/notification/Readme.md
index bc19b95..4cf0538 100644
--- a/packages/notification/Readme.md
+++ b/packages/notification/Readme.md
@@ -6,7 +6,9 @@ These functions are meant to help you easily create notification channels for pr
 
 ### Implementing a `NotificationData` struct
 
-Each notification channel will have a specified data format, which is defined by creating a struct that implements the `NotificationData` trait, which has two methods: `to_cbor` and `channel_id`. The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `message` and `amount`.
+Each notification channel will have a specified data format, which is defined by creating a struct that implements the `NotificationData` trait, which has two methods: `to_cbor` and `channel_id`. 
+
+The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `message` and `amount`.
 
 ```rust
 #[derive(Serialize, Debug, Deserialize, Clone)]
@@ -36,16 +38,19 @@ The `api` parameter for `to_cbor` is not used in this example, but is there for
 
 ### Sending a TxHash notification
 
-To send a notification to a recipient you then create a new `Notification` passing in the address of the recipient along with the notification data you want to send. The following creates a notification for the above `my_channel` and adds it to the contract `Response` as a plaintext attribute.
+To send a notification to a recipient you first create a new `Notification` struct passing in the address of the recipient along with the notification data you want to send. Then to turn it into a `TxHashNotification` execute the `to_txhash_notification` method on the `Notification` by passing in `deps.api`, `env`, and an internal `secret`, which is a randomly generated byte slice that has been stored previously in your contract during initialization.
+
+The following code snippet creates a notification for the above `my_channel` and adds it to the contract `Response` as a plaintext attribute.
 
 ```rust
-let note = Notification::new(
+let notification = Notification::new(
     recipient,
     MyNotificationData {
         "hello".to_string(),
         1000_u128,
     }
-);
+)
+.to_txhash_notification(deps.api, &env, secret)?;
 
 // ... other code
 
@@ -53,8 +58,8 @@ let note = Notification::new(
 Ok(Response::new()
     .set_data(to_binary(&ExecuteAnswer::MyMessage { status: Success } )?)
     .add_attribute_plaintext(
-        note.id_plaintext(),
-        note.data_plaintext(),
+        notification.id_plaintext(),
+        notification.data_plaintext(),
     )
 )
 ```

From dc54f5accc24badbd5ce5a69af1bfd2df367f22c Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Thu, 8 Aug 2024 19:51:32 +1200
Subject: [PATCH 09/29] minor clippy fixes

---
 packages/crypto/src/hkdf.rs | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/packages/crypto/src/hkdf.rs b/packages/crypto/src/hkdf.rs
index b733a09..583b217 100644
--- a/packages/crypto/src/hkdf.rs
+++ b/packages/crypto/src/hkdf.rs
@@ -11,13 +11,13 @@ pub fn hkdf_sha_256(
     info: &[u8],
     length: usize,
 ) -> StdResult<Vec<u8>> {
-    let hk: Hkdf<Sha256> = Hkdf::<Sha256>::new(salt.as_deref().map(|s| s), ikm);
+    let hk: Hkdf<Sha256> = Hkdf::<Sha256>::new(salt.as_deref(), ikm);
     let mut zero_bytes = vec![0u8; length];
-    let mut okm = zero_bytes.as_mut_slice();
-    match hk.expand(info, &mut okm) {
+    let okm = zero_bytes.as_mut_slice();
+    match hk.expand(info, okm) {
         Ok(_) => Ok(okm.to_vec()),
         Err(e) => {
-            return Err(StdError::generic_err(format!("{:?}", e)));
+            Err(StdError::generic_err(format!("{:?}", e)))
         }
     }
 }
@@ -28,13 +28,13 @@ pub fn hkdf_sha_512(
     info: &[u8],
     length: usize,
 ) -> StdResult<Vec<u8>> {
-    let hk: Hkdf<Sha512> = Hkdf::<Sha512>::new(salt.as_deref().map(|s| s), ikm);
+    let hk: Hkdf<Sha512> = Hkdf::<Sha512>::new(salt.as_deref(), ikm);
     let mut zero_bytes = vec![0u8; length];
-    let mut okm = zero_bytes.as_mut_slice();
-    match hk.expand(info, &mut okm) {
+    let okm = zero_bytes.as_mut_slice();
+    match hk.expand(info, okm) {
         Ok(_) => Ok(okm.to_vec()),
         Err(e) => {
-            return Err(StdError::generic_err(format!("{:?}", e)));
+            Err(StdError::generic_err(format!("{:?}", e)))
         }
     }
 }
\ No newline at end of file

From 2d1828c62dff834ee9e6167b8d9670a7e8960cd6 Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Thu, 10 Oct 2024 15:57:59 +1300
Subject: [PATCH 10/29] as use statments

---
 packages/notification/Readme.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/packages/notification/Readme.md b/packages/notification/Readme.md
index 4cf0538..4c305c0 100644
--- a/packages/notification/Readme.md
+++ b/packages/notification/Readme.md
@@ -11,6 +11,11 @@ Each notification channel will have a specified data format, which is defined by
 The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `message` and `amount`.
 
 ```rust
+use cosmwasm_std::{Api, StdError, StdResult};
+use secret_toolkit::notification::NotificationData;
+use serde::{Deserialize, Serialize};
+use minicbor_ser as cbor;
+
 #[derive(Serialize, Debug, Deserialize, Clone)]
 pub struct MyNotificationData {
     pub message: String,

From c28aed1899c8308f4ee261351ae8a875b2a2699d Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Fri, 11 Oct 2024 08:34:31 +1300
Subject: [PATCH 11/29] add channel info types

---
 packages/notification/src/structs.rs | 62 +++++++++++++++++++++++++++-
 1 file changed, 61 insertions(+), 1 deletion(-)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index fbacf47..69df77e 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -1,4 +1,5 @@
-use cosmwasm_std::{Addr, Api, Binary, Env, StdError, StdResult};
+use cosmwasm_std::{Addr, Api, Binary, Env, StdError, StdResult, Uint64};
+use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 
 use crate::{encrypt_notification_data, get_seed, notification_id};
@@ -74,4 +75,63 @@ impl TxHashNotification {
     pub fn data_plaintext(&self) -> String {
         self.encrypted_data.to_base64()
     }
+}
+
+// types for channel info response
+
+#[derive(Serialize, Deserialize, JsonSchema, Clone, Debug)]
+pub struct ChannelInfoData {
+    /// same as query input
+    pub channel: String,
+    /// "counter", "txhash", "bloom"
+    pub mode: String,
+
+    /// txhash / bloom fields only
+    /// if txhash argument was given, this will be its computed Notification ID
+    pub answer_id: Option<Binary>,
+
+    /// bloom fields only
+    /// bloom filter parameters
+    pub parameters: Option<BloomParameters>,
+    /// bloom filter data
+    pub data: Option<Descriptor>,
+
+    /// counter fields only
+    /// current counter value
+    pub counter: Option<Uint64>,
+    /// the next Notification ID
+    pub next_id: Option<Binary>,
+
+    /// counter / txhash field only
+    /// optional CDDL schema definition string for the CBOR-encoded notification data
+    pub cddl: Option<String>,
+}
+
+#[derive(Serialize, Deserialize, JsonSchema, Clone, Debug)]
+pub struct BloomParameters {
+    pub m: u32,
+    pub k: u32,
+    pub h: String,
+}
+
+#[derive(Serialize, Deserialize, JsonSchema, Clone, Debug)]
+pub struct Descriptor {
+    pub r#type: String,
+    pub version: String,
+    pub packet_size: u32,
+    pub data: StructDescriptor,
+}
+
+#[derive(Serialize, Deserialize, JsonSchema, Clone, Debug)]
+pub struct StructDescriptor {
+    pub r#type: String,
+    pub label: String,
+    pub members: Vec<FlatDescriptor>,
+}
+
+#[derive(Serialize, Deserialize, JsonSchema, Clone, Debug)]
+pub struct FlatDescriptor {
+    pub r#type: String,
+    pub label: String,
+    pub description: Option<String>,
 }
\ No newline at end of file

From 0c6a362115ed8b6f9dc01b624945436174ca5a18 Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Fri, 11 Oct 2024 09:15:09 +1300
Subject: [PATCH 12/29] add id to string func

---
 packages/notification/src/structs.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 69df77e..d644165 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -58,6 +58,7 @@ impl<T: NotificationData> Notification<T> {
 pub trait NotificationData {
     fn to_cbor(&self, api: &dyn Api) -> StdResult<Vec<u8>>;
     fn channel_id(&self) -> &str;
+    fn id_to_string() -> String;
 }
 
 #[derive(Serialize, Debug, Deserialize, Clone)]

From f01d675c95a8b1c88eabae9ea7d3a6360e497f59 Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Fri, 11 Oct 2024 09:33:25 +1300
Subject: [PATCH 13/29] make id a const in notification data

---
 packages/notification/src/structs.rs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index d644165..e3501a5 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -33,7 +33,7 @@ impl<T: NotificationData> Notification<T> {
         let seed = get_seed(&notification_for_raw, secret)?;
 
         // get notification id
-        let id = notification_id(&seed, self.data.channel_id(), &tx_hash)?;
+        let id = notification_id(&seed, self.data.channel_id().as_str(), &tx_hash)?;
 
         // use CBOR to encode the data
         let cbor_data = self.data.to_cbor(api)?;
@@ -43,7 +43,7 @@ impl<T: NotificationData> Notification<T> {
             &env.block.height,
             &tx_hash,
             &seed,
-            self.data.channel_id(),
+            self.data.channel_id().as_str(),
             cbor_data,
             block_size,
         )?;
@@ -56,9 +56,11 @@ impl<T: NotificationData> Notification<T> {
 }
 
 pub trait NotificationData {
+    const CHANNEL_ID: String;
     fn to_cbor(&self, api: &dyn Api) -> StdResult<Vec<u8>>;
-    fn channel_id(&self) -> &str;
-    fn id_to_string() -> String;
+    fn channel_id(&self) -> String {
+        Self::CHANNEL_ID
+    }
 }
 
 #[derive(Serialize, Debug, Deserialize, Clone)]

From 746147b375bd9cbd0be5172965c57a162e8e4b1e Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Fri, 11 Oct 2024 09:36:32 +1300
Subject: [PATCH 14/29] make channel id static str

---
 packages/notification/src/structs.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index e3501a5..d1fce20 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -56,10 +56,10 @@ impl<T: NotificationData> Notification<T> {
 }
 
 pub trait NotificationData {
-    const CHANNEL_ID: String;
+    const CHANNEL_ID: &'static str;
     fn to_cbor(&self, api: &dyn Api) -> StdResult<Vec<u8>>;
     fn channel_id(&self) -> String {
-        Self::CHANNEL_ID
+        Self::CHANNEL_ID.to_string()
     }
 }
 

From 8aed92d589dc119f69d20f8538d5a6eea8003d95 Mon Sep 17 00:00:00 2001
From: Ben Adams <darwinzero@gmail.com>
Date: Fri, 11 Oct 2024 10:14:05 +1300
Subject: [PATCH 15/29] add cddl to notificationdata struct

---
 packages/notification/src/structs.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index d1fce20..980dbd0 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -57,10 +57,14 @@ impl<T: NotificationData> Notification<T> {
 
 pub trait NotificationData {
     const CHANNEL_ID: &'static str;
+    const CDDL_SCHEMA: &'static str;
     fn to_cbor(&self, api: &dyn Api) -> StdResult<Vec<u8>>;
     fn channel_id(&self) -> String {
         Self::CHANNEL_ID.to_string()
     }
+    fn cddl_schema(&self) -> String {
+        Self::CDDL_SCHEMA.to_string()
+    }
 }
 
 #[derive(Serialize, Debug, Deserialize, Clone)]

From 73c2ff9320b8186a652f5247f446ca526b164b27 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Tue, 26 Nov 2024 10:34:57 -0800
Subject: [PATCH 16/29] fix: uppercase txhash

---
 packages/notification/src/funcs.rs   | 4 ++--
 packages/notification/src/structs.rs | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/notification/src/funcs.rs b/packages/notification/src/funcs.rs
index 2600dc1..09d194b 100644
--- a/packages/notification/src/funcs.rs
+++ b/packages/notification/src/funcs.rs
@@ -14,7 +14,7 @@ pub const SEED_LEN: usize = 32; // 256 bits
 ///
 pub fn notification_id(seed: &Binary, channel: &str, tx_hash: &String) -> StdResult<Binary> {
     // compute notification ID for this event
-    let material = [channel.as_bytes(), ":".as_bytes(), tx_hash.as_bytes()].concat();
+    let material = [channel.as_bytes(), ":".as_bytes(), tx_hash.to_ascii_uppercase().as_bytes()].concat();
 
     let mut mac: HmacSha256 = HmacSha256::new_from_slice(seed.0.as_slice()).unwrap();
     mac.update(material.as_slice());
@@ -41,7 +41,7 @@ pub fn encrypt_notification_data(
     zero_pad(&mut padded_plaintext, block_size.unwrap_or(NOTIFICATION_BLOCK_SIZE));
 
     let channel_id_bytes = sha_256(channel.as_bytes())[..12].to_vec();
-    let salt_bytes = tx_hash.as_bytes()[..12].to_vec();
+    let salt_bytes = tx_hash.to_ascii_uppercase().as_bytes()[..12].to_vec();
     let nonce: Vec<u8> = channel_id_bytes
         .iter()
         .zip(salt_bytes.iter())
diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 980dbd0..888ec5a 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -28,7 +28,7 @@ impl<T: NotificationData> Notification<T> {
         secret: &[u8],
         block_size: Option<usize>,
     ) -> StdResult<TxHashNotification> {
-        let tx_hash = env.transaction.clone().ok_or(StdError::generic_err("no tx hash found"))?.hash;
+        let tx_hash = env.transaction.clone().ok_or(StdError::generic_err("no tx hash found"))?.hash.to_ascii_uppercase();
         let notification_for_raw = api.addr_canonicalize(self.notification_for.as_str())?;
         let seed = get_seed(&notification_for_raw, secret)?;
 

From 0aea1873800839b955be6dfa09591063c70b35a3 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Tue, 26 Nov 2024 13:08:14 -0800
Subject: [PATCH 17/29] fix: hex decode txhash for salt

---
 packages/notification/Cargo.toml   | 1 +
 packages/notification/src/funcs.rs | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/notification/Cargo.toml b/packages/notification/Cargo.toml
index 16dc3fb..040f77a 100644
--- a/packages/notification/Cargo.toml
+++ b/packages/notification/Cargo.toml
@@ -28,6 +28,7 @@ chacha20poly1305 = { version = "0.10.1", default-features = false, features = ["
 generic-array = "0.14.7"
 hkdf = "0.12.3"
 primitive-types = { version = "0.12.2", default-features = false }
+hex = "0.4.3"
 
 secret-toolkit-crypto = { version = "0.10.0", path = "../crypto", features = [
     "hash", "hkdf"
diff --git a/packages/notification/src/funcs.rs b/packages/notification/src/funcs.rs
index 09d194b..b14bdc2 100644
--- a/packages/notification/src/funcs.rs
+++ b/packages/notification/src/funcs.rs
@@ -41,7 +41,7 @@ pub fn encrypt_notification_data(
     zero_pad(&mut padded_plaintext, block_size.unwrap_or(NOTIFICATION_BLOCK_SIZE));
 
     let channel_id_bytes = sha_256(channel.as_bytes())[..12].to_vec();
-    let salt_bytes = tx_hash.to_ascii_uppercase().as_bytes()[..12].to_vec();
+    let salt_bytes = hex::decode(tx_hash).unwrap().as_bytes()[..12].to_vec();
     let nonce: Vec<u8> = channel_id_bytes
         .iter()
         .zip(salt_bytes.iter())

From 1c60850fd3e41d0aa0320d7f93802db13ce4c134 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Tue, 26 Nov 2024 13:12:08 -0800
Subject: [PATCH 18/29] fix: bytes

---
 packages/notification/src/funcs.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/notification/src/funcs.rs b/packages/notification/src/funcs.rs
index b14bdc2..621af37 100644
--- a/packages/notification/src/funcs.rs
+++ b/packages/notification/src/funcs.rs
@@ -41,7 +41,7 @@ pub fn encrypt_notification_data(
     zero_pad(&mut padded_plaintext, block_size.unwrap_or(NOTIFICATION_BLOCK_SIZE));
 
     let channel_id_bytes = sha_256(channel.as_bytes())[..12].to_vec();
-    let salt_bytes = hex::decode(tx_hash).unwrap().as_bytes()[..12].to_vec();
+    let salt_bytes = hex::decode(tx_hash).unwrap()[..12].to_vec();
     let nonce: Vec<u8> = channel_id_bytes
         .iter()
         .zip(salt_bytes.iter())

From 302510d616b53c7281a471db085404da4f4eba84 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Tue, 26 Nov 2024 22:13:00 -0800
Subject: [PATCH 19/29] feat: data block size

---
 packages/notification/src/structs.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 888ec5a..65ef3d3 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -58,6 +58,7 @@ impl<T: NotificationData> Notification<T> {
 pub trait NotificationData {
     const CHANNEL_ID: &'static str;
     const CDDL_SCHEMA: &'static str;
+    const BLOCK_SIZE: usize;
     fn to_cbor(&self, api: &dyn Api) -> StdResult<Vec<u8>>;
     fn channel_id(&self) -> String {
         Self::CHANNEL_ID.to_string()

From 61e1f363b97e42d715ae111ebacdc86d90bd8680 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Wed, 27 Nov 2024 08:05:31 -0800
Subject: [PATCH 20/29] feat: payload encoding

---
 packages/notification/src/structs.rs | 65 +++++++++++++++++++++-------
 1 file changed, 49 insertions(+), 16 deletions(-)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 65ef3d3..478269a 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -7,12 +7,49 @@ use crate::{encrypt_notification_data, get_seed, notification_id};
 #[derive(Serialize, Debug, Deserialize, Clone)]
 #[cfg_attr(test, derive(Eq, PartialEq))]
 pub struct Notification<T: NotificationData> {
-    // target for the notification
+    /// Recipient address of the notification
     pub notification_for: Addr,
-    // data
+    /// Typed notification data
     pub data: T,
 }
 
+
+pub trait NotificationData {
+    const CHANNEL_ID: &'static str;
+    const CDDL_SCHEMA: &'static str;
+    const ELEMENTS: u64;
+    const PAYLOAD_SIZE: usize;
+
+    fn channel_id(&self) -> String {
+        Self::CHANNEL_ID.to_string()
+    }
+
+    fn cddl_schema(&self) -> String {
+        Self::CDDL_SCHEMA.to_string()
+    }
+
+    fn to_cbor(&self, api: &dyn Api) -> StdResult<Vec<u8>> {
+        // dynamically allocate output buffer
+        let mut buffer = vec![0u8; Self::PAYLOAD_SIZE];
+
+        // create CBOR encoder
+        let mut encoder = Encoder::new(&mut buffer[..]);
+
+        // encode number of elements
+        encoder.array(Self::ELEMENTS).map_err(cbor_to_std_error)?;
+
+        // encode CBOR data
+        self.encode_cbor(api, &mut encoder)?;
+
+        // return buffer
+        Ok(buffer)
+    }
+
+    /// CBOR encodes notification data into the encoder
+    fn encode_cbor(&self, api: &dyn Api, encoder: &mut Encoder<&mut [u8]>) -> StdResult<()>;
+}
+
+
 impl<T: NotificationData> Notification<T> {
     pub fn new(notification_for: Addr, data: T) -> Self {
         Notification {
@@ -28,11 +65,18 @@ impl<T: NotificationData> Notification<T> {
         secret: &[u8],
         block_size: Option<usize>,
     ) -> StdResult<TxHashNotification> {
-        let tx_hash = env.transaction.clone().ok_or(StdError::generic_err("no tx hash found"))?.hash.to_ascii_uppercase();
+        // extract and normalize tx hash
+        let tx_hash = env.transaction.clone()
+            .ok_or(StdError::generic_err("no tx hash found"))?
+            .hash.to_ascii_uppercase();
+
+        // canonicalize notification recipient address
         let notification_for_raw = api.addr_canonicalize(self.notification_for.as_str())?;
+
+        // derive recipient's notification seed
         let seed = get_seed(&notification_for_raw, secret)?;
 
-        // get notification id
+        // derive notification id
         let id = notification_id(&seed, self.data.channel_id().as_str(), &tx_hash)?;
 
         // use CBOR to encode the data
@@ -48,6 +92,7 @@ impl<T: NotificationData> Notification<T> {
             block_size,
         )?;
 
+        // enstruct
         Ok(TxHashNotification {
             id,
             encrypted_data,
@@ -55,18 +100,6 @@ impl<T: NotificationData> Notification<T> {
     }
 }
 
-pub trait NotificationData {
-    const CHANNEL_ID: &'static str;
-    const CDDL_SCHEMA: &'static str;
-    const BLOCK_SIZE: usize;
-    fn to_cbor(&self, api: &dyn Api) -> StdResult<Vec<u8>>;
-    fn channel_id(&self) -> String {
-        Self::CHANNEL_ID.to_string()
-    }
-    fn cddl_schema(&self) -> String {
-        Self::CDDL_SCHEMA.to_string()
-    }
-}
 
 #[derive(Serialize, Debug, Deserialize, Clone)]
 #[cfg_attr(test, derive(Eq, PartialEq))]

From e76c64e89178c13f34cf17cc20aff8f36fcac5e4 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Wed, 27 Nov 2024 08:17:03 -0800
Subject: [PATCH 21/29] fix: dependencies

---
 packages/notification/Cargo.toml     | 2 +-
 packages/notification/src/structs.rs | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/packages/notification/Cargo.toml b/packages/notification/Cargo.toml
index 040f77a..cf4bb87 100644
--- a/packages/notification/Cargo.toml
+++ b/packages/notification/Cargo.toml
@@ -20,7 +20,6 @@ serde = { workspace = true }
 ripemd = { version = "0.1.3", default-features = false }
 schemars = { workspace = true }
 
-minicbor-ser = "0.2.0"
 # rand_core = { version = "0.6.4", default-features = false }
 # rand_chacha = { version = "0.3.1", default-features = false }
 sha2 = "0.10.6"
@@ -29,6 +28,7 @@ generic-array = "0.14.7"
 hkdf = "0.12.3"
 primitive-types = { version = "0.12.2", default-features = false }
 hex = "0.4.3"
+minicbor = "0.25.1"
 
 secret-toolkit-crypto = { version = "0.10.0", path = "../crypto", features = [
     "hash", "hkdf"
diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 478269a..95c68a0 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -1,6 +1,7 @@
 use cosmwasm_std::{Addr, Api, Binary, Env, StdError, StdResult, Uint64};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
+use minicbor_ser::{encode as cbor_encode, Encoder};
 
 use crate::{encrypt_notification_data, get_seed, notification_id};
 
@@ -14,6 +15,10 @@ pub struct Notification<T: NotificationData> {
 }
 
 
+pub fn cbor_to_std_error<T>(e: cbor_encode::Error<T>) -> StdError {
+    StdError::generic_err("CBOR encoding error")
+}
+
 pub trait NotificationData {
     const CHANNEL_ID: &'static str;
     const CDDL_SCHEMA: &'static str;

From a03d708d2162fb31b0548548fb1be707881a9cb5 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Wed, 27 Nov 2024 08:18:40 -0800
Subject: [PATCH 22/29] fix: import

---
 packages/notification/src/structs.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 95c68a0..216948a 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -1,7 +1,7 @@
 use cosmwasm_std::{Addr, Api, Binary, Env, StdError, StdResult, Uint64};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
-use minicbor_ser::{encode as cbor_encode, Encoder};
+use minicbor::{encode as cbor_encode, Encoder};
 
 use crate::{encrypt_notification_data, get_seed, notification_id};
 

From 4912622ea352e3e34c9d5119ff5352d9c1bcbfdb Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Wed, 27 Nov 2024 08:37:21 -0800
Subject: [PATCH 23/29] dev: only pad if block size is given

---
 packages/notification/src/funcs.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/notification/src/funcs.rs b/packages/notification/src/funcs.rs
index 621af37..52809fe 100644
--- a/packages/notification/src/funcs.rs
+++ b/packages/notification/src/funcs.rs
@@ -3,8 +3,6 @@ use secret_toolkit_crypto::{sha_256, hkdf_sha_256, HmacSha256};
 use hkdf::hmac::Mac;
 use crate::cipher_data;
 
-/// default notification block size in bytes
-pub const NOTIFICATION_BLOCK_SIZE: usize = 36;
 pub const SEED_LEN: usize = 32; // 256 bits
 
 ///
@@ -38,7 +36,9 @@ pub fn encrypt_notification_data(
     block_size: Option<usize>,
 ) -> StdResult<Binary> {
     let mut padded_plaintext = plaintext.clone();
-    zero_pad(&mut padded_plaintext, block_size.unwrap_or(NOTIFICATION_BLOCK_SIZE));
+    if let Some(size) = block_size {
+        zero_pad(&mut padded_plaintext, size);
+    }
 
     let channel_id_bytes = sha_256(channel.as_bytes())[..12].to_vec();
     let salt_bytes = hex::decode(tx_hash).unwrap()[..12].to_vec();

From ed701811343a466ab45e1d638731a23477adca3d Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Fri, 6 Dec 2024 15:12:19 -0800
Subject: [PATCH 24/29] dev: add cbor

---
 packages/notification/src/cbor.rs    | 102 +++++++++++++++++++++++++++
 packages/notification/src/funcs.rs   |  24 +++++--
 packages/notification/src/lib.rs     |   4 +-
 packages/notification/src/structs.rs |  10 +--
 4 files changed, 126 insertions(+), 14 deletions(-)
 create mode 100644 packages/notification/src/cbor.rs

diff --git a/packages/notification/src/cbor.rs b/packages/notification/src/cbor.rs
new file mode 100644
index 0000000..b9a2213
--- /dev/null
+++ b/packages/notification/src/cbor.rs
@@ -0,0 +1,102 @@
+use cosmwasm_std::{CanonicalAddr, StdResult, StdError};
+use minicbor::{data as cbor_data, encode as cbor_encode, Encoder};
+
+/// Length of encoding an arry header that holds less than 24 items
+pub const CBL_ARRAY_SHORT: usize = 1;
+
+/// Length of encoding an arry header that holds between 24 and 255 items
+pub const CBL_ARRAY_MEDIUM: usize = 2;
+
+/// Length of encoding an arry header that holds more than 255 items
+pub const CBL_ARRAY_LARGE: usize = 3;
+
+/// Length of encoding a u8 value that is less than 24
+pub const CBL_U8_LESS_THAN_24: usize = 1;
+
+/// Length of encoding a u8 value that is greater than or equal to 24
+pub const CBL_U8: usize = 1 + 1;
+
+/// Length of encoding a u16 value
+pub const CBL_U16: usize = 1 + 2;
+
+/// Length of encoding a u32 value
+pub const CBL_U32: usize = 1 + 4;
+
+/// Length of encoding a u53 value (the maximum safe integer size for javascript)
+pub const CBL_U53: usize = 1 + 8;
+
+/// Length of encoding a u64 value (with the bignum tag attached)
+pub const CBL_BIGNUM_U64: usize = 1 + 1 + 8;
+
+// Length of encoding a timestamp
+pub const CBL_TIMESTAMP: usize = 1 + 1 + 8;
+
+// Length of encoding a 20-byte canonical address
+pub const CBL_ADDRESS: usize = 1 + 20;
+
+/// Wraps the CBOR error to CosmWasm StdError
+pub fn cbor_to_std_error<T>(e: cbor_encode::Error<T>) -> StdError {
+	StdError::generic_err("CBOR encoding error")
+}
+
+/// Extends the minicbor encoder with wrapper functions that handle CBOR errors
+pub trait EncoderExt {
+	fn ext_tag(&mut self, tag: cbor_data::IanaTag) -> StdResult<&mut Self>;
+
+	fn ext_u8(&mut self, value: u8) -> StdResult<&mut Self>;
+	fn ext_u32(&mut self, value: u32) -> StdResult<&mut Self>;
+	fn ext_u64_from_u128(&mut self, value: u128) -> StdResult<&mut Self>;
+	fn ext_address(&mut self, value: CanonicalAddr) -> StdResult<&mut Self>;
+	fn ext_bytes(&mut self, value: &[u8]) -> StdResult<&mut Self>;
+	fn ext_timestamp(&mut self, value: u64) -> StdResult<&mut Self>;
+}
+
+impl<T: cbor_encode::Write> EncoderExt for Encoder<T> {
+	#[inline]
+	fn ext_tag(&mut self, tag: cbor_data::IanaTag) -> StdResult<&mut Self> {
+		 self
+			  .tag(cbor_data::Tag::from(tag))
+					.map_err(cbor_to_std_error)
+	}
+
+	#[inline]
+	fn ext_u8(&mut self, value: u8) -> StdResult<&mut Self> {
+		 self
+			  .u8(value)
+					.map_err(cbor_to_std_error)
+	}
+
+	#[inline]
+	fn ext_u32(&mut self, value: u32) -> StdResult<&mut Self> {
+		 self
+			  .u32(value)
+					.map_err(cbor_to_std_error)
+	}
+
+	#[inline]
+	fn ext_u64_from_u128(&mut self, value: u128) -> StdResult<&mut Self> {
+		 self
+			  .ext_tag(cbor_data::IanaTag::PosBignum)?
+			  .ext_bytes(&value.to_be_bytes()[8..])
+	}
+
+	#[inline]
+	fn ext_address(&mut self, value: CanonicalAddr) -> StdResult<&mut Self> {
+		 self.ext_bytes(&value.as_slice())
+	}
+
+	#[inline]
+	fn ext_bytes(&mut self, value: &[u8]) -> StdResult<&mut Self> {
+		 self
+			  .bytes(&value)
+					.map_err(cbor_to_std_error)
+	}
+
+	#[inline]
+	fn ext_timestamp(&mut self, value: u64) -> StdResult<&mut Self> {
+		 self
+			  .ext_tag(cbor_data::IanaTag::Timestamp)?
+			  .u64(value)
+					.map_err(cbor_to_std_error)
+	}
+}
\ No newline at end of file
diff --git a/packages/notification/src/funcs.rs b/packages/notification/src/funcs.rs
index 52809fe..f6d9431 100644
--- a/packages/notification/src/funcs.rs
+++ b/packages/notification/src/funcs.rs
@@ -14,11 +14,14 @@ pub fn notification_id(seed: &Binary, channel: &str, tx_hash: &String) -> StdRes
     // compute notification ID for this event
     let material = [channel.as_bytes(), ":".as_bytes(), tx_hash.to_ascii_uppercase().as_bytes()].concat();
 
+    // create HMAC from seed
     let mut mac: HmacSha256 = HmacSha256::new_from_slice(seed.0.as_slice()).unwrap();
+
+    // add material to input stream
     mac.update(material.as_slice());
-    let result = mac.finalize();
-    let code_bytes = result.into_bytes();
-    Ok(Binary::from(code_bytes.as_slice()))
+
+    // finalize the digest and convert to CW Binary
+    Ok(Binary::from(mac.finalize().into_bytes().as_slice()))
 }
 
 ///
@@ -35,18 +38,26 @@ pub fn encrypt_notification_data(
     plaintext: Vec<u8>,
     block_size: Option<usize>,
 ) -> StdResult<Binary> {
+    // pad the plaintext to the optionally given block size
     let mut padded_plaintext = plaintext.clone();
     if let Some(size) = block_size {
-        zero_pad(&mut padded_plaintext, size);
+        zero_pad_right(&mut padded_plaintext, size);
     }
 
+    // take the last 12 bytes of the channel name's hash to create the channel ID
     let channel_id_bytes = sha_256(channel.as_bytes())[..12].to_vec();
+
+    // take the last 12 bytes of the tx hash (after hex-decoding) to use for salt
     let salt_bytes = hex::decode(tx_hash).unwrap()[..12].to_vec();
+
+    // generate nonce by XOR'ing channel ID with salt
     let nonce: Vec<u8> = channel_id_bytes
         .iter()
         .zip(salt_bytes.iter())
         .map(|(&b1, &b2)| b1 ^ b2)
         .collect();
+
+    // secure this message by attaching the block height and tx hash to the additional authenticated data
     let aad = format!("{}:{}", block_height, tx_hash);
 
     // encrypt notification data for this event
@@ -68,11 +79,12 @@ pub fn get_seed(addr: &CanonicalAddr, secret: &[u8]) -> StdResult<Binary> {
         addr.as_slice(),
         SEED_LEN,
     )?;
+
     Ok(Binary::from(seed))
 }
 
-/// Take a Vec<u8> and pad it up to a multiple of `block_size`, using 0x00 at the end.
-fn zero_pad(message: &mut Vec<u8>, block_size: usize) -> &mut Vec<u8> {
+/// take a Vec<u8> and pad it up to a multiple of `block_size`, using 0x00 at the end
+fn zero_pad_right(message: &mut Vec<u8>, block_size: usize) -> &mut Vec<u8> {
     let len = message.len();
     let surplus = len % block_size;
     if surplus == 0 {
diff --git a/packages/notification/src/lib.rs b/packages/notification/src/lib.rs
index 3e25990..2161554 100644
--- a/packages/notification/src/lib.rs
+++ b/packages/notification/src/lib.rs
@@ -3,6 +3,8 @@
 pub mod structs;
 pub mod funcs;
 pub mod cipher;
+pub mod cbor;
 pub use structs::*;
 pub use funcs::*;
-pub use cipher::*;
\ No newline at end of file
+pub use cipher::*;
+pub use cbor::*;
diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 216948a..57a88db 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -3,7 +3,7 @@ use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 use minicbor::{encode as cbor_encode, Encoder};
 
-use crate::{encrypt_notification_data, get_seed, notification_id};
+use crate::{encrypt_notification_data, get_seed, notification_id, cbor_to_std_error};
 
 #[derive(Serialize, Debug, Deserialize, Clone)]
 #[cfg_attr(test, derive(Eq, PartialEq))]
@@ -14,11 +14,6 @@ pub struct Notification<T: NotificationData> {
     pub data: T,
 }
 
-
-pub fn cbor_to_std_error<T>(e: cbor_encode::Error<T>) -> StdError {
-    StdError::generic_err("CBOR encoding error")
-}
-
 pub trait NotificationData {
     const CHANNEL_ID: &'static str;
     const CDDL_SCHEMA: &'static str;
@@ -46,7 +41,7 @@ pub trait NotificationData {
         // encode CBOR data
         self.encode_cbor(api, &mut encoder)?;
 
-        // return buffer
+        // return buffer (already right-padded with zero bytes)
         Ok(buffer)
     }
 
@@ -55,6 +50,7 @@ pub trait NotificationData {
 }
 
 
+
 impl<T: NotificationData> Notification<T> {
     pub fn new(notification_for: Addr, data: T) -> Self {
         Notification {

From 0c65bf804d79da8f42fe61e4dd142a9cbb4ecefc Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Fri, 6 Dec 2024 15:15:36 -0800
Subject: [PATCH 25/29] dev: encoder-ext

---
 packages/notification/src/cbor.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/notification/src/cbor.rs b/packages/notification/src/cbor.rs
index b9a2213..6360c38 100644
--- a/packages/notification/src/cbor.rs
+++ b/packages/notification/src/cbor.rs
@@ -51,7 +51,7 @@ pub trait EncoderExt {
 	fn ext_timestamp(&mut self, value: u64) -> StdResult<&mut Self>;
 }
 
-impl<T: cbor_encode::Write> EncoderExt for Encoder<T> {
+pub impl<T: cbor_encode::Write> EncoderExt for Encoder<T> {
 	#[inline]
 	fn ext_tag(&mut self, tag: cbor_data::IanaTag) -> StdResult<&mut Self> {
 		 self
@@ -99,4 +99,4 @@ impl<T: cbor_encode::Write> EncoderExt for Encoder<T> {
 			  .u64(value)
 					.map_err(cbor_to_std_error)
 	}
-}
\ No newline at end of file
+}

From 8602cb64d308368592f5afe9289d61a1a7b85717 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Fri, 6 Dec 2024 15:21:12 -0800
Subject: [PATCH 26/29] fix: revert visibility modifier

---
 packages/notification/src/cbor.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/notification/src/cbor.rs b/packages/notification/src/cbor.rs
index 6360c38..b9a2213 100644
--- a/packages/notification/src/cbor.rs
+++ b/packages/notification/src/cbor.rs
@@ -51,7 +51,7 @@ pub trait EncoderExt {
 	fn ext_timestamp(&mut self, value: u64) -> StdResult<&mut Self>;
 }
 
-pub impl<T: cbor_encode::Write> EncoderExt for Encoder<T> {
+impl<T: cbor_encode::Write> EncoderExt for Encoder<T> {
 	#[inline]
 	fn ext_tag(&mut self, tag: cbor_data::IanaTag) -> StdResult<&mut Self> {
 		 self
@@ -99,4 +99,4 @@ pub impl<T: cbor_encode::Write> EncoderExt for Encoder<T> {
 			  .u64(value)
 					.map_err(cbor_to_std_error)
 	}
-}
+}
\ No newline at end of file

From 0b5335e5c754bc09bc60eec59468bed76fed94d7 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Sat, 7 Dec 2024 08:40:48 -0800
Subject: [PATCH 27/29] dev: group channel

---
 packages/notification/src/structs.rs | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 57a88db..14ab3dd 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -7,14 +7,14 @@ use crate::{encrypt_notification_data, get_seed, notification_id, cbor_to_std_er
 
 #[derive(Serialize, Debug, Deserialize, Clone)]
 #[cfg_attr(test, derive(Eq, PartialEq))]
-pub struct Notification<T: NotificationData> {
+pub struct Notification<T: DirectChannel> {
     /// Recipient address of the notification
     pub notification_for: Addr,
     /// Typed notification data
     pub data: T,
 }
 
-pub trait NotificationData {
+pub trait DirectChannel {
     const CHANNEL_ID: &'static str;
     const CDDL_SCHEMA: &'static str;
     const ELEMENTS: u64;
@@ -50,8 +50,7 @@ pub trait NotificationData {
 }
 
 
-
-impl<T: NotificationData> Notification<T> {
+impl<T: DirectChannel> Notification<T> {
     pub fn new(notification_for: Addr, data: T) -> Self {
         Notification {
             notification_for,
@@ -176,4 +175,19 @@ pub struct FlatDescriptor {
     pub r#type: String,
     pub label: String,
     pub description: Option<String>,
-}
\ No newline at end of file
+}
+
+pub trait GroupChannel<D: DirectChannel> {
+    const CHANNEL_ID: &'static str;
+    const BLOOM_N: usize;
+    const BLOOM_M: u32;
+    const BLOOM_K: u32;
+    const PACKET_SIZE: usize;
+
+    const BLOOM_M_LOG2: u32 = Self::BLOOM_M.ilog2();
+
+    fn build_packet(&self, api: &dyn Api, data: &D) -> StdResult<Vec<u8>>;
+
+    fn notifications(&self) -> Vec<Notification<D>>;
+}
+

From 69eb5a00fca5f534d3210050fe4d3b3cbe681cb8 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Sat, 7 Dec 2024 10:13:27 -0800
Subject: [PATCH 28/29] fix: return notifications as reference

---
 packages/notification/src/structs.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/notification/src/structs.rs b/packages/notification/src/structs.rs
index 14ab3dd..212238a 100644
--- a/packages/notification/src/structs.rs
+++ b/packages/notification/src/structs.rs
@@ -188,6 +188,6 @@ pub trait GroupChannel<D: DirectChannel> {
 
     fn build_packet(&self, api: &dyn Api, data: &D) -> StdResult<Vec<u8>>;
 
-    fn notifications(&self) -> Vec<Notification<D>>;
+    fn notifications(&self) -> &Vec<Notification<D>>;
 }
 

From b30831cdad594cdb7c147aac6f35e4a3165a1692 Mon Sep 17 00:00:00 2001
From: Blake Regalia <blake.regalia@gmail.com>
Date: Sat, 7 Dec 2024 10:32:54 -0800
Subject: [PATCH 29/29] docs: release

---
 packages/notification/Cargo.toml |  4 ++--
 packages/notification/Readme.md  | 41 ++++++++++++++++----------------
 2 files changed, 23 insertions(+), 22 deletions(-)

diff --git a/packages/notification/Cargo.toml b/packages/notification/Cargo.toml
index cf4bb87..99e8192 100644
--- a/packages/notification/Cargo.toml
+++ b/packages/notification/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "secret-toolkit-notification"
-version = "0.10.0"
+version = "0.10.1"
 edition = "2021"
 authors = ["darwinzer0","blake-regalia"]
 license-file = "../../LICENSE"
@@ -30,6 +30,6 @@ primitive-types = { version = "0.12.2", default-features = false }
 hex = "0.4.3"
 minicbor = "0.25.1"
 
-secret-toolkit-crypto = { version = "0.10.0", path = "../crypto", features = [
+secret-toolkit-crypto = { version = "0.10.1", path = "../crypto", features = [
     "hash", "hkdf"
 ] }
\ No newline at end of file
diff --git a/packages/notification/Readme.md b/packages/notification/Readme.md
index 4c305c0..f3375d3 100644
--- a/packages/notification/Readme.md
+++ b/packages/notification/Readme.md
@@ -4,42 +4,43 @@
 
 These functions are meant to help you easily create notification channels for private push notifications in secret contracts (see [SNIP-52 Private Push Notification](https://github.com/SolarRepublic/SNIPs/blob/feat/snip-52/SNIP-52.md)).
 
-### Implementing a `NotificationData` struct
+### Implementing a `DirectChannel` struct
 
-Each notification channel will have a specified data format, which is defined by creating a struct that implements the `NotificationData` trait, which has two methods: `to_cbor` and `channel_id`. 
+Each notification channel will have a specified data format, which is defined by creating a struct that implements the `DirectChannel` trait, which has one method: `encode_cbor`. 
 
-The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `message` and `amount`.
+The following example illustrates how you might implement this for a channel called `my_channel` and notification data containing two fields: `sender` and `amount`.
 
 ```rust
 use cosmwasm_std::{Api, StdError, StdResult};
-use secret_toolkit::notification::NotificationData;
+use secret_toolkit::notification::{EncoderExt, CBL_ARRAY_SHORT, CBL_BIGNUM_U64, CBL_U8, Notification, DirectChannel, GroupChannel};
 use serde::{Deserialize, Serialize};
 use minicbor_ser as cbor;
 
 #[derive(Serialize, Debug, Deserialize, Clone)]
-pub struct MyNotificationData {
-    pub message: String,
+pub struct MyNotification {
+    pub sender: Addr,
     pub amount: u128,
 }
 
-impl NotificationData for MyNotificationData {
-    fn to_cbor(&self, _api: &dyn Api) -> StdResult<Vec<u8>> {
-        let my_data = cbor::to_vec(&(
-            self.message.as_bytes(),
-            self.amount.to_be_bytes(),
-        ))
-        .map_err(|e| StdError::generic_err(format!("{:?}", e)))?;
+impl DirectChannel for MyNotification {
+    const CHANNEL_ID: &'static str = "my_channel";
+    const CDDL_SCHEMA: &'static str = "my_channel=[sender:bstr .size 20,amount:uint .size 8]";
+    const ELEMENTS: u64 = 2;
+    const PAYLOAD_SIZE: usize = CBL_ARRAY_SHORT + CBL_BIGNUM_U64 + CBL_U8;
 
-        Ok(my_data)
-    }
+    fn encode_cbor(&self, api: &dyn Api, encoder: &mut Encoder<&mut [u8]>) -> StdResult<()> {
+        // amount:biguint (8-byte uint)
+        encoder.ext_u64_from_u128(self.amount)?;
+
+        // sender:bstr (20-byte address)
+        let sender_raw = api.addr_canonicalize(sender.as_str())?;
+        encoder.ext_address(sender_raw)?;
 
-    fn channel_id(&self) -> &str {
-        "my_channel"
+        Ok(())
     }
 }
 ```
 
-The `api` parameter for `to_cbor` is not used in this example, but is there for cases where you might want to convert an `Addr` to a `CanonicalAddr` before encoding using CBOR.
 
 ### Sending a TxHash notification
 
@@ -50,8 +51,8 @@ The following code snippet creates a notification for the above `my_channel` and
 ```rust
 let notification = Notification::new(
     recipient,
-    MyNotificationData {
-        "hello".to_string(),
+    MyNotification {
+        sender,
         1000_u128,
     }
 )