no-std compatible cryptodumb-no-std

8 files changed, 235 insertions, 308 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 9cfeef6..e067e1b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -6,20 +6,26 @@ version = 4
 name = "MeshCore"
 version = "0.0.1"
 dependencies = [
+ "aes",
  "arraystring",
  "bytes",
  "cayenne_lpp",
  "chrono",
  "clap",
  "color-eyre",
+ "curve25519-dalek",
+ "ed25519-dalek",
  "hex",
+ "hmac",
  "pcap-file",
  "pcap-file-tokio",
  "pretty_env_logger",
  "serde",
+ "sha2",
  "tinyvec",
  "tokio",
  "toml",
+ "x25519-dalek",
 ]
 
 [[package]]
@@ -38,6 +44,17 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
 
 [[package]]
+name = "aes"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b169f7a6d4742236a0a00c541b845991d0ac43e546831af1249753ab4c3aa3a0"
+dependencies = [
+ "cfg-if",
+ "cipher",
+ "cpufeatures",
+]
+
+[[package]]
 name = "aho-corasick"
 version = "1.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -144,6 +161,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "812e12b5285cc515a9c72a5c1d3b6d46a19dac5acfef5265968c166106e31dd3"
 
 [[package]]
+name = "block-buffer"
+version = "0.10.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3078c7629b62d3f0439517fa394996acacc5cbc91c5a20d8c658e77abd503a71"
+dependencies = [
+ "generic-array",
+]
+
+[[package]]
 name = "byteorder"
 version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -186,6 +212,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "cipher"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "773f3b9af64447d2ce9850330c473515014aa235e6a783b02db81ff39e4a3dad"
+dependencies = [
+ "crypto-common",
+ "inout",
+]
+
+[[package]]
 name = "clap"
 version = "4.5.51"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -259,6 +295,52 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b05b61dc5112cbb17e4b6cd61790d9845d13888356391624cbe7e41efeac1e75"
 
 [[package]]
+name = "cpufeatures"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "59ed5838eebb26a2bb2e58f6d5b5316989ae9d08bab10e0e6d103e656d1b0280"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "crypto-common"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78c8292055d1c1df0cce5d180393dc8cce0abec0a7102adb6c7b1eef6016d60a"
+dependencies = [
+ "generic-array",
+ "typenum",
+]
+
+[[package]]
+name = "curve25519-dalek"
+version = "4.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "97fb8b7c4503de7d6ae7b42ab72a5a59857b4c937ec27a3d4539dba95b5ab2be"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "curve25519-dalek-derive",
+ "digest",
+ "fiat-crypto",
+ "rustc_version",
+ "subtle",
+ "zeroize",
+]
+
+[[package]]
+name = "curve25519-dalek-derive"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f46882e17999c6cc590af592290432be3bce0428cb0d5f8b6715e4dc7b383eb3"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.109",
+]
+
+[[package]]
 name = "derive-into-owned"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -270,6 +352,38 @@ dependencies = [
 ]
 
 [[package]]
+name = "digest"
+version = "0.10.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
+dependencies = [
+ "block-buffer",
+ "crypto-common",
+ "subtle",
+]
+
+[[package]]
+name = "ed25519"
+version = "2.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "115531babc129696a58c64a4fef0a8bf9e9698629fb97e9e40767d235cfbcd53"
+dependencies = [
+ "signature",
+]
+
+[[package]]
+name = "ed25519-dalek"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70e796c081cee67dc755e1a36a0a172b897fab85fc3f6bc48307991f64e4eca9"
+dependencies = [
+ "curve25519-dalek",
+ "ed25519",
+ "sha2",
+ "subtle",
+]
+
+[[package]]
 name = "env_logger"
 version = "0.10.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -299,6 +413,22 @@ dependencies = [
 ]
 
 [[package]]
+name = "fiat-crypto"
+version = "0.2.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28dea519a9695b9977216879a3ebfddf92f1c08c05d984f8996aecd6ecdc811d"
+
+[[package]]
+name = "generic-array"
+version = "0.14.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85649ca51fd72272d7821adaf274ad91c288277713d9c18820d8499a7ff69e9a"
+dependencies = [
+ "typenum",
+ "version_check",
+]
+
+[[package]]
 name = "gimli"
 version = "0.32.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -329,6 +459,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
 
 [[package]]
+name = "hmac"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6c49c37c09c17a53d937dfbb742eb3a961d65a994e6bcdcf37e7399d0cc8ab5e"
+dependencies = [
+ "digest",
+]
+
+[[package]]
 name = "humantime"
 version = "2.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -351,6 +490,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "inout"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "879f10e63c20629ecabbb64a8010319738c66a5cd0c29b02d63d272b03751d01"
+dependencies = [
+ "generic-array",
+]
+
+[[package]]
 name = "is-terminal"
 version = "0.4.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -540,6 +688,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "rand_core"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+
+[[package]]
 name = "redox_syscall"
 version = "0.5.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -584,12 +738,27 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "56f7d92ca342cea22a06f2121d944b4fd82af56988c270852495420f961d4ace"
 
 [[package]]
+name = "rustc_version"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfcb3a22ef46e85b45de6ee7e79d063319ebb6594faafcf1c225ea92ab6e9b92"
+dependencies = [
+ "semver",
+]
+
+[[package]]
 name = "scopeguard"
 version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
 [[package]]
+name = "semver"
+version = "1.0.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d767eb0aabc880b29956c35734170f26ed551a859dbd361d140cdbeca61ab1e2"
+
+[[package]]
 name = "serde"
 version = "1.0.228"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -629,6 +798,17 @@ dependencies = [
 ]
 
 [[package]]
+name = "sha2"
+version = "0.10.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7507d819769d01a365ab707794a4084392c824f54a7a6a7862f8c3d0892b283"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
+
+[[package]]
 name = "sharded-slab"
 version = "0.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -647,6 +827,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "signature"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77549399552de45a898a580c1b41d445bf730df867cc44e6c0233bbc4b8329de"
+
+[[package]]
 name = "smallvec"
 version = "1.15.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -669,6 +855,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
 [[package]]
+name = "subtle"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "13c2bddecc57b384dee18652358fb23172facb8a2c51ccc10d74c157bdea3292"
+
+[[package]]
 name = "syn"
 version = "1.0.109"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -877,6 +1069,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ba73ea9cf16a25df0c8caa16c51acb937d5712a8429db78a3ee29d5dcacd3a65"
 
 [[package]]
+name = "version_check"
+version = "0.9.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
+
+[[package]]
 name = "wasi"
 version = "0.11.1+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -985,3 +1183,19 @@ name = "winnow"
 version = "0.7.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "21a0236b59786fed61e2a80582dd500fe61f18b5dca67a4a067d0bc9039339cf"
+
+[[package]]
+name = "x25519-dalek"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c7e468321c81fb07fa7f4c636c3972b9100f0346e5b6a9f2bd0603a52f7ed277"
+dependencies = [
+ "curve25519-dalek",
+ "rand_core",
+]
+
+[[package]]
+name = "zeroize"
+version = "1.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b97154e67e32c85465826e8bcc1c59429aaaf107c1e4a9e53c8d8ccd5eff88d0"
diff --git a/Cargo.toml b/Cargo.toml
index dd66c69..24e01bc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -21,13 +21,13 @@ arraystring = { version = "0.3.0", default-features = false }
 tinyvec = "1.10.0"
 
 # Crypto functions needed for packet signatures and (en|de)cryption
-# sha2 = { version = "0.10", default-features = false }
-# hmac = { version = "0.12", default-features = false }
-# ed25519-dalek = { version = "2", features = ["hazmat", "rand_core"]}
-# x25519-dalek = { version = "2", features = ["static_secrets"]}
+sha2 = { version = "0.10", default-features = false }
+hmac = { version = "0.12", default-features = false }
+ed25519-dalek = { version = "2", default-features = false, features = ["hazmat"] } # features = ["hazmat", "rand_core"]}
+x25519-dalek = { version = "2", default-features = false } #  features = ["static_secrets"]}
 # rand = "0.8"
-# curve25519-dalek = "4.1.3"
-# aes = "0.8.4"
+curve25519-dalek = "4.1.3"
+aes = { version = "0.8", default-features = false }
 # log = { version = "0.4.28", default-features = false }
 
 # Dependencies needed only for the Packet Analyzer
diff --git a/src/crypto.rs b/src/crypto.rs
index acbb464..034e9cc 100644
--- a/src/crypto.rs
+++ b/src/crypto.rs
@@ -6,7 +6,7 @@ use aes::Aes128;
 use aes::cipher::{BlockDecrypt, BlockEncrypt, generic_array::GenericArray};
 use bytes::{Buf, BufMut, Bytes, BytesMut};
 use curve25519_dalek::MontgomeryPoint;
-use ed25519_dalek::{VerifyingKey, hazmat::ExpandedSecretKey};
+use ed25519_dalek::{SigningKey, VerifyingKey, hazmat::ExpandedSecretKey};
 use hmac::{Hmac, Mac};
 use sha2::Sha256;
 
@@ -82,6 +82,7 @@ impl Clone for PrivateKey {
 
 impl Default for PrivateKey {
     fn default() -> Self {
+        /*
         // To make a key whole-cloth, we need to start with a SigningKey made
         // using a good RNG.  Then we can use that to make an ExpandedSecretKey.
         use ed25519_dalek::SigningKey;
@@ -95,6 +96,8 @@ impl Default for PrivateKey {
         // Then, there are only a few constructors for making an ExpandedSecretKey.
         // Meshcore uses this kind of key, so it's what we need in this application,
         // but it's an uncommon formulation.
+        */
+        let signing_key = SigningKey::from_bytes(&[0u8; 32]);
         let esk = ExpandedSecretKey::from(&signing_key.to_bytes());
         Self(esk)
     }
diff --git a/src/lib.rs b/src/lib.rs
index 5afbd16..c7d327c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,13 +1,7 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
-#[cfg(feature = "std")]
 pub mod crypto;
 
-#[cfg(not(feature = "std"))]
-pub mod no_std_crypto;
-#[cfg(not(feature = "std"))]
-pub use no_std_crypto as crypto;
-
 pub mod string_helper;
 
 #[derive(Debug, PartialEq)]
@@ -24,7 +18,7 @@ pub mod std_identity;
 
 // This version of identity is no-std
 #[cfg(not(feature = "std"))]
-pub(crate) mod no_std_identity;
+pub mod no_std_identity;
 
 pub mod ack;
 pub mod advert;
diff --git a/src/no_std_crypto.rs b/src/no_std_crypto.rs
deleted file mode 100644
index 31f4626..0000000
--- a/src/no_std_crypto.rs
+++ /dev/null
@@ -1,279 +0,0 @@
-use bytes::{Buf, BufMut, Bytes, BytesMut};
-use serde::{Deserialize, Serialize};
-
-use crate::string_helper::NameString;
-
-pub trait Keystore {
-    fn decrypt_and_id_p2p(
-        &self,
-        source: u8,
-        _dest: u8,
-        mac: u16,
-        data: &Bytes,
-    ) -> Option<(Bytes, u32, u32)>;
-
-    fn decrypt_and_id_group(
-        &self,
-        group_hash_prefix: u8,
-        mac: u16,
-        data: &Bytes,
-    ) -> Option<(Bytes, Option<NameString>)>;
-
-    fn decrypt_anon(
-        &self,
-        dest: u8,
-        pub_key: &PublicKey,
-        mac: u16,
-        data: &Bytes,
-    ) -> Option<(Bytes, u32)>;
-}
-
-#[derive(Debug, PartialEq)]
-pub enum MeshcoreCryptoError {
-    KeyLengthError,
-    TryFromSliceError,
-    HexDecodeError,
-    KeyCreationError,
-}
-
-impl core::error::Error for MeshcoreCryptoError {}
-
-impl core::fmt::Display for MeshcoreCryptoError {
-    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
-        match self {
-            MeshcoreCryptoError::KeyLengthError => f.write_str("Key Length Error"),
-            MeshcoreCryptoError::TryFromSliceError => f.write_str("Try From Slice Error"),
-            MeshcoreCryptoError::HexDecodeError => f.write_str("Hex Decode Error"),
-            MeshcoreCryptoError::KeyCreationError => f.write_str("Key Creation Error"),
-        }
-    }
-}
-
-#[derive(Serialize, Deserialize, Clone, PartialEq)]
-pub struct PrivateKey(pub [u8; 32]);
-
-impl core::fmt::Debug for PrivateKey {
-    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
-        f.debug_tuple("PublicKey")
-            .field(&hex::encode(self.0))
-            .finish()
-    }
-}
-
-impl Default for PrivateKey {
-    fn default() -> Self {
-        Self([0; 32])
-    }
-}
-
-impl PrivateKey {
-    pub fn hash_prefix(&self) -> u32 {
-        // The has prefix is the beginning of the public key of the secret
-        let public_key = PublicKey::from(self);
-        public_key.hash_prefix()
-    }
-}
-
-#[derive(Eq, Hash, Serialize, Deserialize, PartialEq, Clone)]
-pub struct PublicKey(pub [u8; 32]);
-
-impl core::fmt::Debug for PublicKey {
-    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
-        f.debug_tuple("PublicKey")
-            .field(&hex::encode(self.0))
-            .finish()
-    }
-}
-
-impl PublicKey {
-    pub fn hash_prefix(&self) -> u32 {
-        let mut bytes = Bytes::copy_from_slice(&self.0);
-        bytes.get_u32()
-    }
-}
-
-#[derive(Clone, Eq, Hash, PartialEq)]
-pub struct SharedSecret([u8; 32]);
-
-impl core::fmt::Debug for SharedSecret {
-    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
-        f.debug_tuple("SharedSecret")
-            .field(&hex::encode(self.0))
-            .finish()
-    }
-}
-
-impl core::str::FromStr for SharedSecret {
-    type Err = MeshcoreCryptoError;
-
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        let mut array = [0_u8; 32];
-
-        // The provided group secrets are only 16 bytes,
-        // but they're zero-paded to be 32.  So, we're
-        // going to get the hex from the string and copy it in.
-        if hex::decode_to_slice(s, &mut array[0..16]).is_err() {
-            return Err(MeshcoreCryptoError::TryFromSliceError);
-        } else {
-            Ok(SharedSecret(array))
-        }
-    }
-}
-
-impl TryFrom<Bytes> for SharedSecret {
-    type Error = MeshcoreCryptoError;
-
-    fn try_from(value: Bytes) -> Result<Self, Self::Error> {
-        if let Some(arr) = value.first_chunk::<32>() {
-            // value.as_array::<32>() {
-            Ok(Self(*arr))
-        } else {
-            Err(MeshcoreCryptoError::KeyLengthError)
-        }
-    }
-}
-
-// This is kinda meaningless because a shared secret only works
-// when it's connected to a key pair, but it needs to exist for
-// Arrayvec.
-impl Default for SharedSecret {
-    fn default() -> Self {
-        Self(Default::default())
-    }
-}
-
-impl SharedSecret {
-    fn get_key(&self) -> &[u8; 16] {
-        // Safety: The size of the slice ensures that this will never be wrong.
-        (&self.0[0..16]).try_into().unwrap()
-    }
-
-    pub fn new_from_group_secret(bytes: Bytes) -> Self {
-        // The group secret is 16-bytes of key with the last 16-bytes set to zero.
-        let mut group_secret = BytesMut::from(bytes);
-        group_secret.reserve(16);
-        group_secret.put(&[0_u8; 16][..]);
-
-        // group_secret.as_array::<32>();
-        let slice = group_secret.first_chunk::<32>().unwrap();
-        SharedSecret(slice.clone())
-    }
-
-    pub fn get_hmac(&self, _ciphertext: &Bytes) -> u16 {
-        // @TODO
-        10
-    }
-
-    pub fn decrypt(&self, ciphertext: &Bytes) -> Bytes {
-        // @TODO
-        ciphertext.clone()
-    }
-
-    pub fn encrypt(&self, plaintext: Bytes) -> Bytes {
-        // @TODO
-        plaintext
-    }
-
-    pub fn hash_prefix(&self) -> u8 {
-        self.0[0]
-    }
-}
-
-// This is just for creating placeholders
-impl Default for PublicKey {
-    fn default() -> Self {
-        PublicKey(Default::default())
-    }
-}
-
-impl TryFrom<&[u8; 32]> for PublicKey {
-    type Error = MeshcoreCryptoError;
-
-    fn try_from(value: &[u8; 32]) -> Result<Self, Self::Error> {
-        Ok(PublicKey(*value))
-    }
-}
-
-impl TryFrom<&[u8]> for PublicKey {
-    type Error = MeshcoreCryptoError;
-
-    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
-        let bytes = Bytes::copy_from_slice(value);
-        Self::try_from(bytes)
-    }
-}
-
-impl TryFrom<Bytes> for PublicKey {
-    type Error = MeshcoreCryptoError;
-
-    fn try_from(value: Bytes) -> Result<Self, Self::Error> {
-        if let Some(arr) = value.first_chunk::<32>() {
-            Self::try_from(arr)
-        } else {
-            Err(MeshcoreCryptoError::KeyLengthError)
-        }
-    }
-}
-
-impl core::str::FromStr for PublicKey {
-    type Err = MeshcoreCryptoError;
-
-    fn from_str(hex_str: &str) -> Result<Self, Self::Err> {
-        if let Ok(hex) = hex::decode(hex_str) {
-            if let Ok(slice) = <[u8; 32]>::try_from(hex) {
-                Self::try_from(&slice)
-            } else {
-                Err(MeshcoreCryptoError::KeyLengthError)
-            }
-        } else {
-            Err(MeshcoreCryptoError::HexDecodeError)
-        }
-    }
-}
-
-impl core::str::FromStr for PrivateKey {
-    type Err = MeshcoreCryptoError;
-
-    fn from_str(hex_str: &str) -> Result<Self, Self::Err> {
-        if let Ok(hex) = hex::decode(hex_str) {
-            if let Ok(bytes) = <[u8; 32]>::try_from(hex) {
-                Ok(PrivateKey(bytes))
-            } else {
-                Err(MeshcoreCryptoError::TryFromSliceError)
-            }
-        } else {
-            Err(MeshcoreCryptoError::HexDecodeError)
-        }
-    }
-}
-
-impl From<&PrivateKey> for PublicKey {
-    fn from(key: &PrivateKey) -> Self {
-        Self(key.0.clone())
-    }
-}
-
-impl PrivateKey {
-    pub fn create_secret(&self, _other: &PublicKey) -> SharedSecret {
-        SharedSecret(self.0)
-    }
-}
-
-impl SharedSecret {
-    pub fn mac_then_decrypt(&self, mac: u16, data: &Bytes) -> Option<Bytes> {
-        // Get the MAC of the message and key to check vailidity
-        let our_mac = self.get_hmac(&data);
-        if our_mac != mac {
-            return None;
-        }
-
-        // Attempt to decrypt the packet itself
-        Some(self.decrypt(&data))
-    }
-
-    pub fn encrypt_then_mac(&self, data: Bytes) -> (u16, Bytes) {
-        let ciphertext = self.encrypt(data);
-        let mac = self.get_hmac(&ciphertext);
-        (mac, ciphertext)
-    }
-}
diff --git a/src/packet.rs b/src/packet.rs
index 86537a7..b1be782 100644
--- a/src/packet.rs
+++ b/src/packet.rs
@@ -1,12 +1,11 @@
-#[cfg(feature = "std")]
-use crate::std_identity::Keystore;
-
+extern crate alloc;
+use alloc::borrow::ToOwned;
 use bytes::{Buf, Bytes};
 use tinyvec::ArrayVec;
 
+use crate::crypto::Keystore;
 use crate::packet_content::PacketContent;
 
-#[cfg(feature = "std")]
 use crate::{
     anon_req::ClearAnonRequest, request::ClearRequest, response::ClearResponse, text::ClearText,
 };
@@ -201,8 +200,7 @@ impl core::fmt::Display for Packet {
 }
 
 impl Packet {
-    #[cfg(feature = "std")]
-    pub fn try_decrypt(&mut self, keystore: &Keystore) -> bool {
+    pub fn try_decrypt<T: Keystore>(&mut self, keystore: &T) -> bool {
         match self.content {
             // Encrypted packet types
             PacketContent::Path(ref mut path) => path.cipher.try_decrypt(keystore),
diff --git a/src/packet_content.rs b/src/packet_content.rs
index a6fa914..5b762d7 100644
--- a/src/packet_content.rs
+++ b/src/packet_content.rs
@@ -11,8 +11,7 @@ use crate::{
 };
 use bytes::{Buf, Bytes};
 
-#[cfg(feature = "std")]
-use crate::std_identity::Keystore;
+use crate::crypto::Keystore;
 
 #[derive(PartialEq, Clone, core::fmt::Debug)]
 pub enum PacketContent {
@@ -152,8 +151,7 @@ impl From<Bytes> for PeerToPeerCipher {
 }
 
 impl PeerToPeerCipher {
-    #[cfg(feature = "std")]
-    pub fn try_decrypt(&mut self, keystore: &Keystore) -> bool {
+    pub fn try_decrypt<T: Keystore>(&mut self, keystore: &T) -> bool {
         let decrypt =
             keystore.decrypt_and_id_p2p(self.source, self.destination, self.mac, &self.ciphertext);
 
diff --git a/src/text.rs b/src/text.rs
index 60d8869..e9efc2e 100644
--- a/src/text.rs
+++ b/src/text.rs
@@ -6,8 +6,7 @@ use crate::string_helper::{
     MessageString, NameString, message_string_from_slice, name_string_from_slice,
 };
 
-#[cfg(feature = "std")]
-use crate::std_identity::Keystore;
+use crate::crypto::Keystore;
 
 #[derive(PartialEq, Debug, Clone)]
 pub struct Text {
@@ -173,13 +172,13 @@ impl From<Bytes> for GroupText {
 }
 
 impl GroupText {
-    #[cfg(feature = "std")]
-    pub fn try_decrypt(&mut self, keysore: &Keystore) -> bool {
+    pub fn try_decrypt<T: Keystore>(&mut self, keysore: &T) -> bool {
         let decrypt_result = keysore.decrypt_and_id_group(self.hash, self.mac, &self.ciphertext);
 
         if let Some((cleartext, group)) = decrypt_result {
             let mut cleartext = ClearText::from(cleartext);
-            cleartext.crypto_recipient = group;
+            // @TODO: what?
+            // cleartext.crypto_recipient = group;
             self.cleartext = Some(cleartext);
             true
         } else {