refactor: 将 DTLS 本地依赖迁移到 libs 目录

libs/dtls/src/content.rs

@@ -0,0 +1,85 @@
+use std::io::{Read, Write};
+
+use super::alert::*;
+use super::application_data::*;
+use super::change_cipher_spec::*;
+use super::handshake::*;
+use crate::error::*;
+
+/// ## Specifications
+///
+/// * [RFC 4346 §6.2.1]
+///
+/// [RFC 4346 §6.2.1]: https://tools.ietf.org/html/rfc4346#section-6.2.1
+#[derive(Default, Copy, Clone, PartialEq, Eq, Debug)]
+pub enum ContentType {
+    ChangeCipherSpec = 20,
+    Alert = 21,
+    Handshake = 22,
+    ApplicationData = 23,
+    #[default]
+    Invalid,
+}
+
+impl From<u8> for ContentType {
+    fn from(val: u8) -> Self {
+        match val {
+            20 => ContentType::ChangeCipherSpec,
+            21 => ContentType::Alert,
+            22 => ContentType::Handshake,
+            23 => ContentType::ApplicationData,
+            _ => ContentType::Invalid,
+        }
+    }
+}
+
+#[derive(PartialEq, Debug, Clone)]
+pub enum Content {
+    ChangeCipherSpec(ChangeCipherSpec),
+    Alert(Alert),
+    Handshake(Handshake),
+    ApplicationData(ApplicationData),
+}
+
+impl Content {
+    pub fn content_type(&self) -> ContentType {
+        match self {
+            Content::ChangeCipherSpec(c) => c.content_type(),
+            Content::Alert(c) => c.content_type(),
+            Content::Handshake(c) => c.content_type(),
+            Content::ApplicationData(c) => c.content_type(),
+        }
+    }
+
+    pub fn size(&self) -> usize {
+        match self {
+            Content::ChangeCipherSpec(c) => c.size(),
+            Content::Alert(c) => c.size(),
+            Content::Handshake(c) => c.size(),
+            Content::ApplicationData(c) => c.size(),
+        }
+    }
+
+    pub fn marshal<W: Write>(&self, writer: &mut W) -> Result<()> {
+        match self {
+            Content::ChangeCipherSpec(c) => c.marshal(writer),
+            Content::Alert(c) => c.marshal(writer),
+            Content::Handshake(c) => c.marshal(writer),
+            Content::ApplicationData(c) => c.marshal(writer),
+        }
+    }
+
+    pub fn unmarshal<R: Read>(content_type: ContentType, reader: &mut R) -> Result<Self> {
+        match content_type {
+            ContentType::ChangeCipherSpec => Ok(Content::ChangeCipherSpec(
+                ChangeCipherSpec::unmarshal(reader)?,
+            )),
+            ContentType::Alert => Ok(Content::Alert(Alert::unmarshal(reader)?)),
+            ContentType::Handshake => Ok(Content::Handshake(Handshake::unmarshal(reader)?)),
+            ContentType::ApplicationData => Ok(Content::ApplicationData(
+                ApplicationData::unmarshal(reader)?,
+            )),
+            _ => Err(Error::ErrInvalidContentType),
+        }
+    }
+}