Merge pull request #1843 from TheBlueMatt/2022-11-fix-bp-exit-docs
[rust-lightning] / lightning / src / util / ser.rs
index 8fb72a8f9fe643f56cfc259e5b7214b56a4fb761..7c4ba7fd50f99888745a6944971c10f3f00f77a9 100644 (file)
 //! A very simple serialization framework which is used to serialize/deserialize messages as well
 //! as ChannelsManagers and ChannelMonitors.
 
-use prelude::*;
-use io::{self, Read, Write};
-use io_extras::{copy, sink};
+use crate::prelude::*;
+use crate::io::{self, Read, Write};
+use crate::io_extras::{copy, sink};
 use core::hash::Hash;
-use sync::Mutex;
+use crate::sync::Mutex;
 use core::cmp;
+use core::convert::TryFrom;
+use core::ops::Deref;
 
-use bitcoin::secp256k1::Signature;
-use bitcoin::secp256k1::key::{PublicKey, SecretKey};
+use bitcoin::secp256k1::{PublicKey, SecretKey};
 use bitcoin::secp256k1::constants::{PUBLIC_KEY_SIZE, SECRET_KEY_SIZE, COMPACT_SIGNATURE_SIZE};
+use bitcoin::secp256k1::ecdsa::Signature;
+use bitcoin::blockdata::constants::ChainHash;
 use bitcoin::blockdata::script::Script;
 use bitcoin::blockdata::transaction::{OutPoint, Transaction, TxOut};
 use bitcoin::consensus;
@@ -28,10 +31,10 @@ use bitcoin::hashes::sha256d::Hash as Sha256dHash;
 use bitcoin::hash_types::{Txid, BlockHash};
 use core::marker::Sized;
 use core::time::Duration;
-use ln::msgs::DecodeError;
-use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
+use crate::ln::msgs::DecodeError;
+use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
 
-use util::byte_utils::{be48_to_array, slice_to_be48};
+use crate::util::byte_utils::{be48_to_array, slice_to_be48};
 
 /// serialization buffer size
 pub const MAX_BUF_SIZE: usize = 64 * 1024;
@@ -134,6 +137,13 @@ impl<R: Read> Read for FixedLengthReader<R> {
        }
 }
 
+impl<R: Read> LengthRead for FixedLengthReader<R> {
+       #[inline]
+       fn total_bytes(&self) -> u64 {
+               self.total_bytes
+       }
+}
+
 /// A Read which tracks whether any bytes have been read at all. This allows us to distinguish
 /// between "EOF reached before we started" and "EOF reached mid-read".
 pub(crate) struct ReadTrackingReader<R: Read> {
@@ -174,6 +184,7 @@ pub trait Writeable {
        }
 
        /// Writes self out to a Vec<u8>
+       #[cfg(test)]
        fn encode_with_len(&self) -> Vec<u8> {
                let mut msg = VecWriter(Vec::new());
                0u16.write(&mut msg).unwrap();
@@ -219,6 +230,29 @@ pub trait ReadableArgs<P>
        fn read<R: Read>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 }
 
+/// A std::io::Read that also provides the total bytes available to read.
+pub(crate) trait LengthRead: Read {
+       /// The total number of bytes available to read.
+       fn total_bytes(&self) -> u64;
+}
+
+/// A trait that various higher-level rust-lightning types implement allowing them to be read in
+/// from a Read given some additional set of arguments which is required to deserialize, requiring
+/// the implementer to provide the total length of the read.
+pub(crate) trait LengthReadableArgs<P> where Self: Sized
+{
+       /// Reads a Self in from the given LengthRead
+       fn read<R: LengthRead>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
+}
+
+/// A trait that various higher-level rust-lightning types implement allowing them to be read in
+/// from a Read, requiring the implementer to provide the total length of the read.
+pub(crate) trait LengthReadable where Self: Sized
+{
+       /// Reads a Self in from the given LengthRead
+       fn read<R: LengthRead>(reader: &mut R) -> Result<Self, DecodeError>;
+}
+
 /// A trait that various rust-lightning types implement allowing them to (maybe) be read in from a Read
 ///
 /// (C-not exported) as we only export serialization to/from byte arrays instead
@@ -243,38 +277,11 @@ impl<T: Readable> Readable for OptionDeserWrapper<T> {
                Ok(Self(Some(Readable::read(reader)?)))
        }
 }
-
-/// Wrapper to write each element of a Vec with no length prefix
-pub(crate) struct VecWriteWrapper<'a, T: Writeable>(pub &'a Vec<T>);
-impl<'a, T: Writeable> Writeable for VecWriteWrapper<'a, T> {
-       #[inline]
-       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
-               for ref v in self.0.iter() {
-                       v.write(writer)?;
-               }
-               Ok(())
-       }
-}
-
-/// Wrapper to read elements from a given stream until it reaches the end of the stream.
-pub(crate) struct VecReadWrapper<T>(pub Vec<T>);
-impl<T: MaybeReadable> Readable for VecReadWrapper<T> {
-       #[inline]
-       fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
-               let mut values = Vec::new();
-               loop {
-                       let mut track_read = ReadTrackingReader::new(&mut reader);
-                       match MaybeReadable::read(&mut track_read) {
-                               Ok(Some(v)) => { values.push(v); },
-                               Ok(None) => { },
-                               // If we failed to read any bytes at all, we reached the end of our TLV
-                               // stream and have simply exhausted all entries.
-                               Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
-                               Err(e) => return Err(e),
-                       }
-               }
-               Ok(Self(values))
-       }
+/// When handling default_values, we want to map the default-value T directly
+/// to a OptionDeserWrapper<T> in a way that works for `field: T = t;` as
+/// well. Thus, we assume `Into<T> for T` does nothing and use that.
+impl<T: Readable> From<T> for OptionDeserWrapper<T> {
+       fn from(t: T) -> OptionDeserWrapper<T> { OptionDeserWrapper(Some(t)) }
 }
 
 pub(crate) struct U48(pub u64);
@@ -300,7 +307,7 @@ impl Readable for U48 {
 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 /// you're looking for an example of a variable-length integer to use for your own project, move
 /// along, this is a rather poor design.
-pub(crate) struct BigSize(pub u64);
+pub struct BigSize(pub u64);
 impl Writeable for BigSize {
        #[inline]
        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
@@ -360,8 +367,8 @@ impl Readable for BigSize {
 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 /// encapsulates such integers implementing Readable/Writeable for them.
-#[cfg_attr(test, derive(PartialEq, Debug))]
-pub(crate) struct HighZeroBytesDroppedVarInt<T>(pub T);
+#[cfg_attr(test, derive(PartialEq, Eq, Debug))]
+pub(crate) struct HighZeroBytesDroppedBigSize<T>(pub T);
 
 macro_rules! impl_writeable_primitive {
        ($val_type:ty, $len: expr) => {
@@ -371,7 +378,7 @@ macro_rules! impl_writeable_primitive {
                                writer.write_all(&self.to_be_bytes())
                        }
                }
-               impl Writeable for HighZeroBytesDroppedVarInt<$val_type> {
+               impl Writeable for HighZeroBytesDroppedBigSize<$val_type> {
                        #[inline]
                        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
                                // Skip any full leading 0 bytes when writing (in BE):
@@ -386,9 +393,9 @@ macro_rules! impl_writeable_primitive {
                                Ok(<$val_type>::from_be_bytes(buf))
                        }
                }
-               impl Readable for HighZeroBytesDroppedVarInt<$val_type> {
+               impl Readable for HighZeroBytesDroppedBigSize<$val_type> {
                        #[inline]
-                       fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedVarInt<$val_type>, DecodeError> {
+                       fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedBigSize<$val_type>, DecodeError> {
                                // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
                                // the high bytes being dropped. To do so, we start reading into the middle of buf
                                // and then convert the appropriate number of bytes with extra high bytes out of
@@ -404,7 +411,7 @@ macro_rules! impl_writeable_primitive {
                                        let first_byte = $len - ($len - total_read_len);
                                        let mut bytes = [0; $len];
                                        bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
-                                       Ok(HighZeroBytesDroppedVarInt(<$val_type>::from_be_bytes(bytes)))
+                                       Ok(HighZeroBytesDroppedBigSize(<$val_type>::from_be_bytes(bytes)))
                                } else {
                                        // If the encoding had extra zero bytes, return a failure even though we know
                                        // what they meant (as the TLV test vectors require this)
@@ -412,6 +419,9 @@ macro_rules! impl_writeable_primitive {
                                }
                        }
                }
+               impl From<$val_type> for HighZeroBytesDroppedBigSize<$val_type> {
+                       fn from(val: $val_type) -> Self { Self(val) }
+               }
        }
 }
 
@@ -475,16 +485,91 @@ macro_rules! impl_array {
        );
 }
 
-//TODO: performance issue with [u8; size] with impl_array!()
-impl_array!(3); // for rgb
+impl_array!(3); // for rgb, ISO 4712 code
 impl_array!(4); // for IPv4
-impl_array!(10); // for OnionV2
+impl_array!(12); // for OnionV2
 impl_array!(16); // for IPv6
 impl_array!(32); // for channel id & hmac
 impl_array!(PUBLIC_KEY_SIZE); // for PublicKey
 impl_array!(COMPACT_SIGNATURE_SIZE); // for Signature
 impl_array!(1300); // for OnionPacket.hop_data
 
+impl Writeable for [u16; 8] {
+       #[inline]
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               for v in self.iter() {
+                       w.write_all(&v.to_be_bytes())?
+               }
+               Ok(())
+       }
+}
+
+impl Readable for [u16; 8] {
+       #[inline]
+       fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+               let mut buf = [0u8; 16];
+               r.read_exact(&mut buf)?;
+               let mut res = [0u16; 8];
+               for (idx, v) in res.iter_mut().enumerate() {
+                       *v = (buf[idx] as u16) << 8 | (buf[idx + 1] as u16)
+               }
+               Ok(res)
+       }
+}
+
+/// For variable-length values within TLV record where the length is encoded as part of the record.
+/// Used to prevent encoding the length twice.
+pub(crate) struct WithoutLength<T>(pub T);
+
+impl Writeable for WithoutLength<&String> {
+       #[inline]
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               w.write_all(self.0.as_bytes())
+       }
+}
+impl Readable for WithoutLength<String> {
+       #[inline]
+       fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+               let v: WithoutLength<Vec<u8>> = Readable::read(r)?;
+               Ok(Self(String::from_utf8(v.0).map_err(|_| DecodeError::InvalidValue)?))
+       }
+}
+impl<'a> From<&'a String> for WithoutLength<&'a String> {
+       fn from(s: &'a String) -> Self { Self(s) }
+}
+
+impl<'a, T: Writeable> Writeable for WithoutLength<&'a Vec<T>> {
+       #[inline]
+       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+               for ref v in self.0.iter() {
+                       v.write(writer)?;
+               }
+               Ok(())
+       }
+}
+
+impl<T: MaybeReadable> Readable for WithoutLength<Vec<T>> {
+       #[inline]
+       fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
+               let mut values = Vec::new();
+               loop {
+                       let mut track_read = ReadTrackingReader::new(&mut reader);
+                       match MaybeReadable::read(&mut track_read) {
+                               Ok(Some(v)) => { values.push(v); },
+                               Ok(None) => { },
+                               // If we failed to read any bytes at all, we reached the end of our TLV
+                               // stream and have simply exhausted all entries.
+                               Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
+                               Err(e) => return Err(e),
+                       }
+               }
+               Ok(Self(values))
+       }
+}
+impl<'a, T> From<&'a Vec<T>> for WithoutLength<&'a Vec<T>> {
+       fn from(v: &'a Vec<T>) -> Self { Self(v) }
+}
+
 // HashMap
 impl<K, V> Writeable for HashMap<K, V>
        where K: Writeable + Eq + Hash,
@@ -799,6 +884,19 @@ impl Readable for BlockHash {
        }
 }
 
+impl Writeable for ChainHash {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               w.write_all(self.as_bytes())
+       }
+}
+
+impl Readable for ChainHash {
+       fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+               let buf: [u8; 32] = Readable::read(r)?;
+               Ok(ChainHash::from(&buf[..]))
+       }
+}
+
 impl Writeable for OutPoint {
        fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
                self.txid.write(w)?;
@@ -822,7 +920,7 @@ macro_rules! impl_consensus_ser {
        ($bitcoin_type: ty) => {
                impl Writeable for $bitcoin_type {
                        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
-                               match self.consensus_encode(WriterWriteAdaptor(writer)) {
+                               match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
                                        Ok(_) => Ok(()),
                                        Err(e) => Err(e),
                                }
@@ -913,6 +1011,75 @@ impl Readable for String {
        }
 }
 
+/// Represents a hostname for serialization purposes.
+/// Only the character set and length will be validated.
+/// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
+/// Its length is guaranteed to be representable by a single byte.
+/// This serialization is used by BOLT 7 hostnames.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct Hostname(String);
+impl Hostname {
+       /// Returns the length of the hostname.
+       pub fn len(&self) -> u8 {
+               (&self.0).len() as u8
+       }
+}
+impl Deref for Hostname {
+       type Target = String;
+
+       fn deref(&self) -> &Self::Target {
+               &self.0
+       }
+}
+impl From<Hostname> for String {
+       fn from(hostname: Hostname) -> Self {
+               hostname.0
+       }
+}
+impl TryFrom<Vec<u8>> for Hostname {
+       type Error = ();
+
+       fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
+               if let Ok(s) = String::from_utf8(bytes) {
+                       Hostname::try_from(s)
+               } else {
+                       Err(())
+               }
+       }
+}
+impl TryFrom<String> for Hostname {
+       type Error = ();
+
+       fn try_from(s: String) -> Result<Self, Self::Error> {
+               if s.len() <= 255 && s.chars().all(|c|
+                       c.is_ascii_alphanumeric() ||
+                       c == '.' ||
+                       c == '-'
+               ) {
+                       Ok(Hostname(s))
+               } else {
+                       Err(())
+               }
+       }
+}
+impl Writeable for Hostname {
+       #[inline]
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               self.len().write(w)?;
+               w.write_all(self.as_bytes())
+       }
+}
+impl Readable for Hostname {
+       #[inline]
+       fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
+               let len: u8 = Readable::read(r)?;
+               let mut vec = Vec::with_capacity(len.into());
+               vec.resize(len.into(), 0);
+               r.read_exact(&mut vec)?;
+               Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
+       }
+}
+
 impl Writeable for Duration {
        #[inline]
        fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
@@ -928,3 +1095,29 @@ impl Readable for Duration {
                Ok(Duration::new(secs, nanos))
        }
 }
+
+#[cfg(test)]
+mod tests {
+       use core::convert::TryFrom;
+       use crate::util::ser::{Readable, Hostname, Writeable};
+
+       #[test]
+       fn hostname_conversion() {
+               assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
+
+               assert!(Hostname::try_from(String::from("\"")).is_err());
+               assert!(Hostname::try_from(String::from("$")).is_err());
+               assert!(Hostname::try_from(String::from("⚡")).is_err());
+               let mut large_vec = Vec::with_capacity(256);
+               large_vec.resize(256, b'A');
+               assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
+       }
+
+       #[test]
+       fn hostname_serialization() {
+               let hostname = Hostname::try_from(String::from("test")).unwrap();
+               let mut buf: Vec<u8> = Vec::new();
+               hostname.write(&mut buf).unwrap();
+               assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
+       }
+}