Initial commit

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/extensions/extension_data/supported_groups.rs

@@ -0,0 +1,101 @@
+use heapless::Vec;
+
+use crate::{
+    ProtocolError,
+    buffer::CryptoBuffer,
+    parse_buffer::{ParseBuffer, ParseError},
+};
+
+#[derive(Copy, Clone, Debug, PartialEq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub enum NamedGroup {
+    Secp256r1,
+    Secp384r1,
+    Secp521r1,
+    X25519,
+    X448,
+
+    Ffdhe2048,
+    Ffdhe3072,
+    Ffdhe4096,
+    Ffdhe6144,
+    Ffdhe8192,
+
+    X25519MLKEM768,
+    SecP256r1MLKEM768,
+    SecP384r1MLKEM1024,
+}
+
+impl NamedGroup {
+    pub fn parse(buf: &mut ParseBuffer) -> Result<Self, ParseError> {
+        match buf.read_u16()? {
+            0x0017 => Ok(Self::Secp256r1),
+            0x0018 => Ok(Self::Secp384r1),
+            0x0019 => Ok(Self::Secp521r1),
+            0x001D => Ok(Self::X25519),
+            0x001E => Ok(Self::X448),
+
+            0x0100 => Ok(Self::Ffdhe2048),
+            0x0101 => Ok(Self::Ffdhe3072),
+            0x0102 => Ok(Self::Ffdhe4096),
+            0x0103 => Ok(Self::Ffdhe6144),
+            0x0104 => Ok(Self::Ffdhe8192),
+
+            0x11EB => Ok(Self::SecP256r1MLKEM768),
+            0x11EC => Ok(Self::X25519MLKEM768),
+            0x11ED => Ok(Self::SecP384r1MLKEM1024),
+
+            _ => Err(ParseError::InvalidData),
+        }
+    }
+
+    pub fn as_u16(self) -> u16 {
+        match self {
+            Self::Secp256r1 => 0x0017,
+            Self::Secp384r1 => 0x0018,
+            Self::Secp521r1 => 0x0019,
+            Self::X25519 => 0x001D,
+            Self::X448 => 0x001E,
+
+            Self::Ffdhe2048 => 0x0100,
+            Self::Ffdhe3072 => 0x0101,
+            Self::Ffdhe4096 => 0x0102,
+            Self::Ffdhe6144 => 0x0103,
+            Self::Ffdhe8192 => 0x0104,
+
+            Self::SecP256r1MLKEM768 => 0x11EB,
+            Self::X25519MLKEM768 => 0x11EC,
+            Self::SecP384r1MLKEM1024 => 0x11ED,
+        }
+    }
+
+    pub fn encode(self, buf: &mut CryptoBuffer) -> Result<(), ProtocolError> {
+        buf.push_u16(self.as_u16())
+            .map_err(|_| ProtocolError::EncodeError)
+    }
+}
+
+#[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub struct SupportedGroups<const N: usize> {
+    pub supported_groups: Vec<NamedGroup, N>,
+}
+
+impl<const N: usize> SupportedGroups<N> {
+    pub fn parse(buf: &mut ParseBuffer) -> Result<Self, ParseError> {
+        let data_length = buf.read_u16()? as usize;
+
+        Ok(Self {
+            supported_groups: buf.read_list::<_, N>(data_length, NamedGroup::parse)?,
+        })
+    }
+
+    pub fn encode(&self, buf: &mut CryptoBuffer) -> Result<(), ProtocolError> {
+        buf.with_u16_length(|buf| {
+            for g in &self.supported_groups {
+                g.encode(buf)?;
+            }
+            Ok(())
+        })
+    }
+}