client: add ciphersuite and version arrays (#242)

This adds arrays of ciphersuites and versions as suggested in #165 and #203.

CHANGELOG.md

@@ -11,6 +11,9 @@
    rustls_result (#227).
  - rustls_session_store_get_callback and rustls_session_store_put_callback now
    return uint32_t (#227).
+ - Added arrays ALL_CIPHER_SUITES, DEFAULT_CIPHER_SUITES, ALL_VERSIONS, and
+   DEFAULT_VERSIONS as more convenient alternatives to
+   rustls_default_ciphersuites_get_entry(), etc.
 
 ## 0.8.2 (2021-11-13)
 

src/cipher.rs

@@ -123,6 +123,94 @@ pub extern "C" fn rustls_default_ciphersuites_get_entry(
     }
 }
 
+/// Rustls' list of supported cipher suites. This is an array of pointers, and
+/// its length is given by `RUSTLS_ALL_CIPHER_SUITES_LEN`. The pointers will
+/// always be valid. The contents and order of this array may change between
+/// releases.
+#[no_mangle]
+static mut RUSTLS_ALL_CIPHER_SUITES: [*const rustls_supported_ciphersuite; 9] = [
+    &rustls::cipher_suite::TLS13_AES_256_GCM_SHA384 as *const SupportedCipherSuite as *const _,
+    &rustls::cipher_suite::TLS13_AES_128_GCM_SHA256 as *const SupportedCipherSuite as *const _,
+    &rustls::cipher_suite::TLS13_CHACHA20_POLY1305_SHA256 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
+        as *const SupportedCipherSuite as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
+        as *const SupportedCipherSuite as *const _,
+];
+
+/// The length of the array `RUSTLS_ALL_CIPHER_SUITES`.
+#[no_mangle]
+pub static RUSTLS_ALL_CIPHER_SUITES_LEN: usize = unsafe { RUSTLS_ALL_CIPHER_SUITES.len() };
+
+/// Rustls' list of default cipher suites. This is an array of pointers, and
+/// its length is given by `RUSTLS_DEFAULT_CIPHER_SUITES_LEN`. The pointers
+/// will always be valid. The contents and order of this array may change
+/// between releases.
+#[no_mangle]
+pub static mut RUSTLS_DEFAULT_CIPHER_SUITES: [*const rustls_supported_ciphersuite; 9] = [
+    &rustls::cipher_suite::TLS13_AES_256_GCM_SHA384 as *const SupportedCipherSuite as *const _,
+    &rustls::cipher_suite::TLS13_AES_128_GCM_SHA256 as *const SupportedCipherSuite as *const _,
+    &rustls::cipher_suite::TLS13_CHACHA20_POLY1305_SHA256 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
+        as *const SupportedCipherSuite as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 as *const SupportedCipherSuite
+        as *const _,
+    &rustls::cipher_suite::TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
+        as *const SupportedCipherSuite as *const _,
+];
+
+/// The length of the array `RUSTLS_DEFAULT_CIPHER_SUITES`.
+#[no_mangle]
+pub static RUSTLS_DEFAULT_CIPHER_SUITES_LEN: usize = unsafe { RUSTLS_DEFAULT_CIPHER_SUITES.len() };
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn all_cipher_suites_arrays() {
+        assert_eq!(RUSTLS_ALL_CIPHER_SUITES_LEN, ALL_CIPHER_SUITES.len());
+        for (original, ffi) in ALL_CIPHER_SUITES
+            .iter()
+            .zip(unsafe { RUSTLS_ALL_CIPHER_SUITES }.iter().copied())
+        {
+            let ffi_cipher_suite = try_ref_from_ptr!(ffi);
+            assert_eq!(original, ffi_cipher_suite);
+        }
+    }
+
+    #[test]
+    fn default_cipher_suites_arrays() {
+        assert_eq!(
+            RUSTLS_DEFAULT_CIPHER_SUITES_LEN,
+            DEFAULT_CIPHER_SUITES.len()
+        );
+        for (original, ffi) in DEFAULT_CIPHER_SUITES
+            .iter()
+            .zip(unsafe { RUSTLS_DEFAULT_CIPHER_SUITES }.iter().copied())
+        {
+            let ffi_cipher_suite = try_ref_from_ptr!(ffi);
+            assert_eq!(original, ffi_cipher_suite);
+        }
+    }
+}
+
 /// The complete chain of certificates to send during a TLS handshake,
 /// plus a private key that matches the end-entity (leaf) certificate.
 /// Corresponds to `CertifiedKey` in the Rust API.

src/client.rs

@@ -112,12 +112,14 @@ impl rustls_client_config_builder {
     /// resulting rustls_client_config. Specify cipher suites in preference
     /// order; the `cipher_suites` parameter must point to an array containing
     /// `len` pointers to `rustls_supported_ciphersuite` previously obtained
-    /// from `rustls_all_ciphersuites_get_entry()`. Set the TLS protocol
-    /// versions to use when negotiating a TLS session.
+    /// from `rustls_all_ciphersuites_get_entry()`, or to a provided array,
+    /// RUSTLS_DEFAULT_CIPHER_SUITES or RUSTLS_ALL_CIPHER_SUITES. Set the TLS
+    /// protocol versions to use when negotiating a TLS session.
     ///
     /// `tls_version` is the version of the protocol, as defined in rfc8446,
     /// ch. 4.2.1 and end of ch. 5.1. Some values are defined in
-    /// `rustls_tls_version` for convenience.
+    /// `rustls_tls_version` for convenience, and the arrays
+    /// RUSTLS_DEFAULT_VERSIONS or RUSTLS_ALL_VERSIONS can be used directly.
     ///
     /// `versions` will only be used during the call and the application retains
     /// ownership. `len` is the number of consecutive `uint16_t` pointed to by `versions`.

src/enums.rs

@@ -9,3 +9,50 @@ pub enum rustls_tls_version {
     Tlsv1_2 = 0x0303,
     Tlsv1_3 = 0x0304,
 }
+
+/// Rustls' list of supported protocol versions. The length of the array is
+/// given by `RUSTLS_ALL_VERSIONS_LEN`.
+#[no_mangle]
+pub static RUSTLS_ALL_VERSIONS: [u16; 2] = [
+    rustls_tls_version::Tlsv1_3 as u16,
+    rustls_tls_version::Tlsv1_2 as u16,
+];
+
+/// The length of the array `RUSTLS_ALL_VERSIONS`.
+#[no_mangle]
+pub static RUSTLS_ALL_VERSIONS_LEN: usize = RUSTLS_ALL_VERSIONS.len();
+
+/// Rustls' default list of protocol versions. The length of the array is
+/// given by `RUSTLS_DEFAULT_VERSIONS_LEN`.
+#[no_mangle]
+pub static RUSTLS_DEFAULT_VERSIONS: [u16; 2] = [
+    rustls_tls_version::Tlsv1_3 as u16,
+    rustls_tls_version::Tlsv1_2 as u16,
+];
+
+/// The length of the array `RUSTLS_DEFAULT_VERSIONS`.
+#[no_mangle]
+pub static RUSTLS_DEFAULT_VERSIONS_LEN: usize = RUSTLS_DEFAULT_VERSIONS.len();
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use rustls::{ALL_VERSIONS, DEFAULT_VERSIONS};
+
+    #[test]
+    fn all_versions_arrays() {
+        assert_eq!(RUSTLS_ALL_VERSIONS_LEN, ALL_VERSIONS.len());
+        for (original, ffi) in ALL_VERSIONS.iter().zip(RUSTLS_ALL_VERSIONS.iter()) {
+            assert_eq!(original.version.get_u16(), *ffi);
+        }
+    }
+
+    #[test]
+    fn default_versions_arrays() {
+        assert_eq!(RUSTLS_DEFAULT_VERSIONS_LEN, DEFAULT_VERSIONS.len());
+        for (original, ffi) in DEFAULT_VERSIONS.iter().zip(RUSTLS_DEFAULT_VERSIONS.iter()) {
+            assert_eq!(original.version.get_u16(), *ffi);
+        }
+    }
+}

src/rustls.h

@@ -460,6 +460,20 @@ typedef uint32_t (*rustls_session_store_get_callback)(rustls_session_store_userd
  */
 typedef uint32_t (*rustls_session_store_put_callback)(rustls_session_store_userdata userdata, const struct rustls_slice_bytes *key, const struct rustls_slice_bytes *val);
 
+extern const size_t RUSTLS_ALL_CIPHER_SUITES_LEN;
+
+extern const struct rustls_supported_ciphersuite *RUSTLS_DEFAULT_CIPHER_SUITES[9];
+
+extern const size_t RUSTLS_DEFAULT_CIPHER_SUITES_LEN;
+
+extern const uint16_t RUSTLS_ALL_VERSIONS[2];
+
+extern const size_t RUSTLS_ALL_VERSIONS_LEN;
+
+extern const uint16_t RUSTLS_DEFAULT_VERSIONS[2];
+
+extern const size_t RUSTLS_DEFAULT_VERSIONS_LEN;
+
 /**
  * Returns a static string containing the rustls-ffi version as well as the
  * rustls version. The string is alive for the lifetime of the program and does
@@ -648,12 +662,14 @@ struct rustls_client_config_builder *rustls_client_config_builder_new(void);
  * resulting rustls_client_config. Specify cipher suites in preference
  * order; the `cipher_suites` parameter must point to an array containing
  * `len` pointers to `rustls_supported_ciphersuite` previously obtained
- * from `rustls_all_ciphersuites_get_entry()`. Set the TLS protocol
- * versions to use when negotiating a TLS session.
+ * from `rustls_all_ciphersuites_get_entry()`, or to a provided array,
+ * RUSTLS_DEFAULT_CIPHER_SUITES or RUSTLS_ALL_CIPHER_SUITES. Set the TLS
+ * protocol versions to use when negotiating a TLS session.
  *
  * `tls_version` is the version of the protocol, as defined in rfc8446,
  * ch. 4.2.1 and end of ch. 5.1. Some values are defined in
- * `rustls_tls_version` for convenience.
+ * `rustls_tls_version` for convenience, and the arrays
+ * RUSTLS_DEFAULT_VERSIONS or RUSTLS_ALL_VERSIONS can be used directly.
  *
  * `versions` will only be used during the call and the application retains
  * ownership. `len` is the number of consecutive `uint16_t` pointed to by `versions`.