WIP tls: add feature to build against OpenSSL

Cargo.toml

@@ -25,6 +25,9 @@ default = ["boringssl-vendored"]
 # Build vendored BoringSSL library.
 boringssl-vendored = []
 
+# Build quiche against OpenSSL instead of BoringSSL.
+openssl = ["pkg-config"]
+
 # Generate pkg-config metadata file for libquiche.
 pkg-config-meta = []
 
@@ -33,6 +36,7 @@ default-features = false
 
 [build-dependencies]
 cmake = "0.1"
+pkg-config = { version = "0.3", optional = true }
 
 [dependencies]
 log = "0.4"

src/build.rs

@@ -153,7 +153,7 @@ Cflags: -I${{includedir}}
 }
 
 fn main() {
-    if cfg!(feature = "boringssl-vendored") {
+    if cfg!(feature = "boringssl-vendored") && !cfg!(feature = "openssl") {
         let bssl_dir = std::env::var("QUICHE_BSSL_PATH").unwrap_or_else(|_| {
             get_boringssl_cmake_config()
                 .build_target("bssl")
@@ -173,6 +173,14 @@ fn main() {
         println!("cargo:rustc-link-lib=static=ssl");
     }
 
+    if cfg!(feature = "openssl") {
+        #[cfg(feature = "openssl")]
+        pkg_config::probe_library("libcrypto").unwrap();
+
+        #[cfg(feature = "openssl")]
+        pkg_config::probe_library("libssl").unwrap();
+    }
+
     if cfg!(feature = "pkg-config-meta") {
         write_pkg_config();
     }

src/tls.rs

@@ -780,6 +780,7 @@ extern {
     );
 
     // SSL
+    #[cfg(not(feature = "openssl"))]
     fn SSL_get_ex_new_index(
         argl: c_long, argp: *const c_void, unused: *const c_void,
         dup_unused: *const c_void, free_func: *const c_void,
@@ -799,11 +800,14 @@ extern {
 
     fn SSL_get_current_cipher(ssl: *mut SSL) -> *const SSL_CIPHER;
 
+    #[cfg(not(feature = "openssl"))]
     fn SSL_set_min_proto_version(ssl: *mut SSL, version: u16);
+    #[cfg(not(feature = "openssl"))]
     fn SSL_set_max_proto_version(ssl: *mut SSL, version: u16);
 
     fn SSL_set_quiet_shutdown(ssl: *mut SSL, mode: c_int);
 
+    #[cfg(not(feature = "openssl"))]
     fn SSL_set_tlsext_host_name(ssl: *mut SSL, name: *const c_char) -> c_int;
 
     fn SSL_set_quic_transport_params(
@@ -834,6 +838,11 @@ extern {
 
     fn SSL_clear(ssl: *mut SSL) -> c_int;
 
+    #[cfg(feature = "openssl")]
+    fn SSL_ctrl(
+        ssl: *mut SSL, cmd: c_int, larg: c_long, parg: *mut c_void,
+    ) -> c_int;
+
     fn SSL_free(ssl: *mut SSL);
 
     // SSL_CIPHER
@@ -858,4 +867,70 @@ extern {
     fn ERR_peek_error() -> c_uint;
 
     fn ERR_error_string_n(err: c_uint, buf: *const u8, len: usize);
+
+    // CRYPTO
+    #[cfg(feature = "openssl")]
+    fn CRYPTO_get_ex_new_index(
+        class_index: c_int, argl: c_long, argp: *const c_void,
+        new_func: *const c_void, dup_func: *const c_void,
+        free_func: *const c_void,
+    ) -> c_int;
+}
+
+// OpenSSL compatibility functions.
+//
+// These don't 100% follow the OpenSSL API (e.g. some arguments have slightly
+// different types) in order to make them compatible with the BoringSSL API.
+
+#[cfg(feature = "openssl")]
+#[allow(non_snake_case)]
+unsafe fn SSL_set_min_proto_version(s: *mut SSL, version: u16) {
+    const SSL_CTRL_SET_MIN_PROTO_VERSION: c_int = 123;
+
+    SSL_ctrl(
+        s,
+        SSL_CTRL_SET_MIN_PROTO_VERSION,
+        version as c_long,
+        ptr::null_mut(),
+    );
+}
+
+#[cfg(feature = "openssl")]
+#[allow(non_snake_case)]
+unsafe fn SSL_set_max_proto_version(s: *mut SSL, version: u16) {
+    const SSL_CTRL_SET_MAX_PROTO_VERSION: c_int = 124;
+
+    SSL_ctrl(
+        s,
+        SSL_CTRL_SET_MAX_PROTO_VERSION,
+        version as c_long,
+        ptr::null_mut(),
+    );
+}
+
+#[cfg(feature = "openssl")]
+#[allow(non_snake_case)]
+unsafe fn SSL_set_tlsext_host_name(s: *mut SSL, name: *const c_char) -> c_int {
+    const SSL_CTRL_SET_TLSEXT_HOSTNAME: c_int = 55;
+
+    #[allow(non_upper_case_globals)]
+    const TLSEXT_NAMETYPE_host_name: c_long = 0;
+
+    SSL_ctrl(
+        s,
+        SSL_CTRL_SET_TLSEXT_HOSTNAME,
+        TLSEXT_NAMETYPE_host_name,
+        name as *mut c_void,
+    )
+}
+
+#[cfg(feature = "openssl")]
+#[allow(non_snake_case)]
+unsafe fn SSL_get_ex_new_index(
+    argl: c_long, argp: *const c_void, newf: *const c_void, dupf: *const c_void,
+    freef: *const c_void,
+) -> c_int {
+    const CRYPTO_EX_INDEX_SSL: c_int = 0;
+
+    CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_SSL, argl, argp, newf, dupf, freef)
 }