From 5ed77df197afc33c04569edcd3db5993a695fbae Mon Sep 17 00:00:00 2001
From: Onur Aslan <onuraslan@gmail.com>
Date: Fri, 29 Jul 2016 12:11:53 +0300
Subject: [PATCH] Implement save_der for X509 and X509Req

---
 openssl-sys/src/lib.rs    |  3 +++
 openssl/src/x509/mod.rs   | 22 ++++++++++++++++++++++
 openssl/src/x509/tests.rs | 13 +++++++++++++
 3 files changed, 38 insertions(+)

diff --git a/openssl-sys/src/lib.rs b/openssl-sys/src/lib.rs
index 96a24e48..1e0d5fe5 100644
--- a/openssl-sys/src/lib.rs
+++ b/openssl-sys/src/lib.rs
@@ -841,6 +841,9 @@ extern "C" {
     pub fn X509_REQ_add_extensions(req: *mut X509_REQ, exts: *mut stack_st_X509_EXTENSION) -> c_int;
     pub fn X509_REQ_sign(x: *mut X509_REQ, pkey: *mut EVP_PKEY, md: *const EVP_MD) -> c_int;
 
+    pub fn i2d_X509_bio(b: *mut BIO, x: *mut X509) -> c_int;
+    pub fn i2d_X509_REQ_bio(b: *mut BIO, x: *mut X509_REQ) -> c_int;
+
     pub fn i2d_RSA_PUBKEY(k: *mut RSA, buf: *const *mut u8) -> c_int;
     pub fn d2i_RSA_PUBKEY(k: *const *mut RSA, buf: *const *const u8, len: c_uint) -> *mut RSA;
     pub fn i2d_RSAPrivateKey(k: *mut RSA, buf: *const *mut u8) -> c_int;
diff --git a/openssl/src/x509/mod.rs b/openssl/src/x509/mod.rs
index 3150cc6e..396d50df 100644
--- a/openssl/src/x509/mod.rs
+++ b/openssl/src/x509/mod.rs
@@ -532,6 +532,17 @@ impl<'ctx> X509<'ctx> {
         }
         io::copy(&mut mem_bio, writer).map_err(StreamError).map(|_| ())
     }
+
+    /// Returns a DER serialized form of the certificate
+    pub fn save_der(&self) -> Result<Vec<u8>, SslError> {
+        let mut mem_bio = try!(MemBio::new());
+        unsafe {
+            ffi::i2d_X509_bio(mem_bio.get_handle(), self.handle);
+        }
+        let mut v = Vec::new();
+        try!(io::copy(&mut mem_bio, &mut v).map_err(StreamError));
+        Ok(v)
+    }
 }
 
 extern "C" {
@@ -637,6 +648,17 @@ impl X509Req {
         }
         io::copy(&mut mem_bio, writer).map_err(StreamError).map(|_| ())
     }
+
+    /// Returns a DER serialized form of the CSR
+    pub fn save_der(&self) -> Result<Vec<u8>, SslError> {
+        let mut mem_bio = try!(MemBio::new());
+        unsafe {
+            ffi::i2d_X509_REQ_bio(mem_bio.get_handle(), self.handle);
+        }
+        let mut v = Vec::new();
+        try!(io::copy(&mut mem_bio, &mut v).map_err(StreamError));
+        Ok(v)
+    }
 }
 
 impl Drop for X509Req {
diff --git a/openssl/src/x509/tests.rs b/openssl/src/x509/tests.rs
index f547a982..5d9b30ab 100644
--- a/openssl/src/x509/tests.rs
+++ b/openssl/src/x509/tests.rs
@@ -92,6 +92,19 @@ fn test_cert_loading() {
     assert_eq!(fingerprint, hash_vec);
 }
 
+#[test]
+fn test_save_der() {
+    let cert_path = Path::new("test/cert.pem");
+    let mut file = File::open(&cert_path)
+                       .ok()
+                       .expect("Failed to open `test/cert.pem`");
+
+    let cert = X509::from_pem(&mut file).ok().expect("Failed to load PEM");
+
+    let der = cert.save_der().unwrap();
+    assert!(!der.is_empty());
+}
+
 #[test]
 fn test_subject_read_cn() {
     let cert_path = Path::new("test/cert.pem");