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Basic Crypto

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This commit is contained in:
Alex Emmet 2026-06-21 16:11:00 +02:00
commit 94f2280570
10 changed files with 568 additions and 79 deletions
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131
codec/src/data_value.rs
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@ -7,6 +7,9 @@ use std::io::Cursor;
use mtp_type_map::DataTypeId;
#[cfg(feature = "crypto")]
use mtp_crypto::{AeadDecrypt, AeadEncrypt};
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum DataKind {
Bool,
@ -44,7 +47,7 @@ pub enum DataValue {
Container(Vec<(DataTypeId, DataValue)>),
#[cfg(feature = "crypto")]
EncryptedContainer(Vec<(DataTypeId, DataValue)>),
EncryptedContainer(Vec<u8>),
Null,
}
@ -52,26 +55,36 @@ pub enum DataValue {
impl DataValue {
/*
* Container format:
* [2 bytes u16 entry_count] // length of the container
* [2 bytes u16 entry_count] // number of entries
* [1 byte kind] // DataValue kind marker
* [if kind == BOOL_TRUE or BOOL_FALSE:]
* [1 byte key] // DataTypes discriminant
* [2 bytes u16 key] // DataTypeId discriminant
* [else:]
* [2 bytes u16 payload_len] // length of the value payload
* [1 byte key] // DataTypes discriminant
* [4 bytes u32 payload_len] // length of the value payload
* [2 bytes u16 key] // DataTypeId discriminant
* [payload_len bytes payload] // value data (interpreted based on kind)
*
* Array format (same as container but no keys):
* [2 bytes u16 entry_count]
* for each entry:
* [1 byte kind]
* [if kind == BOOL_TRUE or BOOL_FALSE:]
* (no payload)
* [else:]
* [4 bytes u32 payload_len]
* [payload_len bytes payload]
*
* Kind markers:
* 0x01 => BoolTrue
* 0x02 => BoolFalse
* 0x03 => Signed Number (i64, 8 bytes big-endian)
* 0x04 => Unsigned Number (u64, 8 bytes big-endian)
* 0x05 => Float (1 byte exponent, 3 bytes mantissa)
* 0x03 => Signed Number (i128, 16 bytes big-endian)
* 0x04 => Unsigned Number (u128, 16 bytes big-endian)
* 0x05 => Float (1 byte exponent, 4 bytes mantissa)
* 0x06 => Str (UTF-8 bytes)
* 0x07 => Bytes
* 0x08 => Array (nested container format)
* 0x09 => Container (nested container format)
* 0x0A => EncryptedContainer (nested container format)
* 0x08 => Array
* 0x09 => Container
* 0x0A => EncryptedContainer (4 bytes u32 len + encrypted bytes)
* 0x0B => Null
*/
const KIND_BOOL_TRUE: u8 = 0x01;
@ -184,13 +197,49 @@ impl DataValue {
}
#[cfg(feature = "crypto")]
pub fn as_encrypted_container(&self) -> Option<Vec<(DataTypeId, DataValue)>> {
pub fn as_encrypted_container(&self) -> Option<Vec<u8>> {
match self {
DataValue::EncryptedContainer(c) => Some(c.clone()),
_ => None,
}
}
/// Decrypt an `EncryptedContainer` in-place, replacing it with the
/// deserialized `Container`. Returns `None` if decryption or
/// deserialization fails.
#[cfg(feature = "crypto")]
pub fn decrypt_into_container(
&mut self,
cipher: &impl AeadDecrypt,
aad: &[u8],
) -> Option<()> {
let data = self.as_encrypted_container()?;
let plaintext = cipher.decrypt(&data, aad).ok()?;
let dv = DataValue::from_bytes(&plaintext)?;
match dv {
DataValue::Container(entries) => {
*self = DataValue::Container(entries);
Some(())
}
_ => None,
}
}
/// Encrypt a `Container` into an `EncryptedContainer` in-place.
/// Returns `None` if the value is not a `Container` or encryption fails.
#[cfg(feature = "crypto")]
pub fn encrypt_container(
&mut self,
cipher: &impl AeadEncrypt,
aad: &[u8],
) -> Option<()> {
let entries = self.as_container()?;
let plaintext = DataValue::Container(entries).to_bytes();
let ct = cipher.encrypt(&plaintext, aad).ok()?;
*self = DataValue::EncryptedContainer(ct);
Some(())
}
pub fn as_map(&self) -> Option<BTreeMap<DataTypeId, DataValue>> {
match self {
DataValue::Container(c) => {
@ -258,8 +307,7 @@ impl DataValue {
buf.push(kind);
if kind == Self::KIND_BOOL_TRUE || kind == Self::KIND_BOOL_FALSE {
let key = u8::try_from(key.0).unwrap_or(0);
buf.push(key);
let _ = buf.write_u16::<BigEndian>(key.0);
return true;
}
@ -268,16 +316,10 @@ impl DataValue {
return false;
}
let len_u16 = match u16::try_from(payload.len()) {
Ok(v) => v,
Err(_) => return false,
};
if buf.write_u16::<BigEndian>(len_u16).is_err() {
if buf.write_u32::<BigEndian>(payload.len() as u32).is_err() {
return false;
}
let key = u8::try_from(key.0).unwrap_or(0);
buf.push(key);
let _ = buf.write_u16::<BigEndian>(key.0);
buf.extend_from_slice(&payload);
true
}
@ -313,12 +355,7 @@ impl DataValue {
return false;
}
let len_u16 = match u16::try_from(payload.len()) {
Ok(v) => v,
Err(_) => return false,
};
if buf.write_u16::<BigEndian>(len_u16).is_err() {
if buf.write_u32::<BigEndian>(payload.len() as u32).is_err() {
return false;
}
buf.extend_from_slice(&payload);
@ -368,9 +405,8 @@ impl DataValue {
Some(())
}
#[cfg(feature = "crypto")]
DataValue::EncryptedContainer(entries) => {
let bytes = Self::encode_container(entries);
buf.extend_from_slice(&bytes);
DataValue::EncryptedContainer(data) => {
buf.extend_from_slice(data);
Some(())
}
@ -418,7 +454,7 @@ impl DataValue {
continue;
}
let len = cursor.read_u16::<BigEndian>().ok()? as usize;
let len = cursor.read_u32::<BigEndian>().ok()? as usize;
let key = DataTypeId(cursor.read_u16::<BigEndian>().ok()?);
let start = cursor.position() as usize;
@ -457,7 +493,7 @@ impl DataValue {
continue;
}
let len = cursor.read_u16::<BigEndian>().ok()? as usize;
let len = cursor.read_u32::<BigEndian>().ok()? as usize;
let start = cursor.position() as usize;
let end = start.checked_add(len)?;
if end > cursor.get_ref().len() {
@ -510,6 +546,17 @@ impl DataValue {
cursor.set_position(end as u64);
Some(DataValue::Str(s))
}
Self::KIND_BYTES => {
let len = payload_len?;
let start = cursor.position() as usize;
let end = start.checked_add(len)?;
if end > cursor.get_ref().len() {
return None;
}
let b = cursor.get_ref()[start..end].to_vec();
cursor.set_position(end as u64);
Some(DataValue::Bytes(b))
}
Self::KIND_ARRAY => {
let start = cursor.position() as usize;
let len = payload_len?;
@ -542,25 +589,19 @@ impl DataValue {
}
#[cfg(feature = "crypto")]
Self::KIND_ENCRYPTED_CONTAINER => {
let start = cursor.position() as usize;
let len = payload_len?;
let start = cursor.position() as usize;
let end = start.checked_add(len)?;
if end > cursor.get_ref().len() {
return None;
}
let mut inner = Cursor::new(&cursor.get_ref()[start..end]);
let c = Self::try_read_container(&mut inner)?;
if inner.position() as usize != len {
return None;
}
let data = cursor.get_ref()[start..end].to_vec();
cursor.set_position(end as u64);
if let DataValue::Container(entries) = c {
Some(DataValue::EncryptedContainer(entries))
} else {
None
}
Some(DataValue::EncryptedContainer(data))
}
Self::KIND_NULL => Some(DataValue::Null),
#[cfg(not(feature = "crypto"))]
0x0A => None,
_ => None,
}
}
@ -660,7 +701,7 @@ impl Hash for DataValue {
c.hash(state);
}
Null => {
6u8.hash(state);
7u8.hash(state);
}
}
}