Add session cache size accessors

openssl-sys/src/ssl.rs

@@ -697,6 +697,8 @@ pub const SSL_CTRL_EXTRA_CHAIN_CERT: c_int = 14;
 pub const SSL_CTRL_OPTIONS: c_int = 32;
 pub const SSL_CTRL_MODE: c_int = 33;
 pub const SSL_CTRL_SET_READ_AHEAD: c_int = 41;
+pub const SSL_CTRL_SET_SESS_CACHE_SIZE: c_int = 42;
+pub const SSL_CTRL_GET_SESS_CACHE_SIZE: c_int = 43;
 pub const SSL_CTRL_SET_SESS_CACHE_MODE: c_int = 44;
 pub const SSL_CTRL_SET_TLSEXT_SERVERNAME_CB: c_int = 53;
 pub const SSL_CTRL_SET_TLSEXT_SERVERNAME_ARG: c_int = 54;
@@ -1224,6 +1226,14 @@ extern "C" {
     pub fn SSL_get_ex_data_X509_STORE_CTX_idx() -> c_int;
 }
 
+pub unsafe fn SSL_CTX_sess_set_cache_size(ctx: *mut SSL_CTX, t: c_long) -> c_long {
+    SSL_CTX_ctrl(ctx, SSL_CTRL_SET_SESS_CACHE_SIZE, t, ptr::null_mut())
+}
+
+pub unsafe fn SSL_CTX_sess_get_cache_size(ctx: *mut SSL_CTX) -> c_long {
+    SSL_CTX_ctrl(ctx, SSL_CTRL_GET_SESS_CACHE_SIZE, 0, ptr::null_mut())
+}
+
 pub unsafe fn SSL_CTX_set_session_cache_mode(ctx: *mut SSL_CTX, m: c_long) -> c_long {
     SSL_CTX_ctrl(ctx, SSL_CTRL_SET_SESS_CACHE_MODE, m, ptr::null_mut())
 }

openssl/src/ssl/mod.rs

@@ -1675,6 +1675,17 @@ impl SslContextBuilder {
         }
     }
 
+    /// Sets the context's session cache size limit, returning the previous limit.
+    ///
+    /// A value of 0 means that the cache size is unbounded.
+    ///
+    /// This corresponds to [`SSL_CTX_sess_get_cache_size`].
+    ///
+    /// [`SSL_CTX_sess_get_cache_size`]: https://www.openssl.org/docs/man1.0.2/man3/SSL_CTX_sess_set_cache_size.html
+    pub fn set_session_cache_size(&mut self, size: i32) -> i64 {
+        unsafe { ffi::SSL_CTX_sess_set_cache_size(self.as_ptr(), size.into()).into() }
+    }
+
     /// Consumes the builder, returning a new `SslContext`.
     pub fn build(self) -> SslContext {
         self.0
@@ -1873,6 +1884,17 @@ impl SslContextRef {
     pub unsafe fn remove_session(&self, session: &SslSessionRef) -> bool {
         ffi::SSL_CTX_remove_session(self.as_ptr(), session.as_ptr()) != 0
     }
+
+    /// Returns the context's session cache size limit.
+    ///
+    /// A value of 0 means that the cache size is unbounded.
+    ///
+    /// This corresponds to [`SSL_CTX_sess_get_cache_size`].
+    ///
+    /// [`SSL_CTX_sess_get_cache_size`]: https://www.openssl.org/docs/man1.0.2/man3/SSL_CTX_sess_set_cache_size.html
+    pub fn session_cache_size(&self) -> i64 {
+        unsafe { ffi::SSL_CTX_sess_get_cache_size(self.as_ptr()).into() }
+    }
 }
 
 /// Information about the state of a cipher.

openssl/src/ssl/test.rs

@@ -1849,3 +1849,11 @@ fn openssl_cipher_name() {
 
     assert_eq!(super::cipher_name("asdf"), "(NONE)");
 }
+
+#[test]
+fn session_cache_size() {
+    let mut ctx = SslContext::builder(SslMethod::tls()).unwrap();
+    ctx.set_session_cache_size(1234);
+    let ctx = ctx.build();
+    assert_eq!(ctx.session_cache_size(), 1234);
+}