use less alloc in hkdf

bytedance · Sep 17, 2024 · a312801 · a312801
1 parent 4a55bd9
commit a312801
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Showing 3 changed files with 6 additions and 3 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/lib/g3-dpi/Cargo.toml b/lib/g3-dpi/Cargo.toml
@@ -12,6 +12,7 @@ fnv.workspace = true
 bytes.workspace = true
 memchr.workspace = true
 fixedbitset.workspace = true
+smallvec = { workspace = true, optional = true }
 openssl = { workspace = true, optional = true }
 g3-types = { workspace = true, features = ["http"] }
 
@@ -20,4 +21,4 @@ hex-literal.workspace = true
 
 [features]
 default = []
-quic = ["dep:openssl"]
+quic = ["dep:openssl", "dep:smallvec"]
diff --git a/lib/g3-dpi/src/parser/quic/packet/hkdf.rs b/lib/g3-dpi/src/parser/quic/packet/hkdf.rs
@@ -18,10 +18,11 @@ use openssl::error::ErrorStack;
 use openssl::md::Md;
 use openssl::pkey::Id;
 use openssl::pkey_ctx::{HkdfMode, PkeyCtx};
+use smallvec::SmallVec;
 
-fn build_info_from_label(label: &[u8], output_len: u16) -> Vec<u8> {
+fn build_info_from_label(label: &[u8], output_len: u16) -> SmallVec<[u8; 32]> {
  let label_len = 6 + label.len() as u8;
- let mut info = Vec::with_capacity(2 + 1 + label_len as usize + 1);
+ let mut info: SmallVec<[u8; 32]> = SmallVec::with_capacity(2 + 1 + label_len as usize + 1);
  let l_bytes = output_len.to_be_bytes();
  info.extend_from_slice(&l_bytes);
  info.push(label_len);