Add implementation of OCSP nonce functions.

- References sfackler#1045.
- Add test for creation of OCSP request.
- With and without a nonce.
- Add custom return/error type for ocsp::check_nonce.
- Fix signature of ocsp::BasicResponseRef::copy_nonce.
- Add Error::description implementation as required by older versions of Rust.

Author: scolby33

openssl-sys/src/ocsp.rs

@@ -66,6 +66,7 @@ cfg_if! {
 
 extern "C" {
     pub fn OCSP_request_add0_id(r: *mut OCSP_REQUEST, id: *mut OCSP_CERTID) -> *mut OCSP_ONEREQ;
+    pub fn OCSP_request_add1_nonce(req: *mut OCSP_REQUEST, val: *mut c_uchar, len: c_int) -> c_int;
 
     pub fn OCSP_resp_find_status(
         bs: *mut OCSP_BASICRESP,
@@ -85,6 +86,9 @@ extern "C" {
 
     pub fn OCSP_response_status(resp: *mut OCSP_RESPONSE) -> c_int;
     pub fn OCSP_response_get1_basic(resp: *mut OCSP_RESPONSE) -> *mut OCSP_BASICRESP;
+    pub fn OCSP_basic_add1_nonce(resp: *mut OCSP_BASICRESP, val: *mut c_uchar, len: c_int)
+        -> c_int;
+    pub fn OCSP_copy_nonce(resp: *mut OCSP_BASICRESP, req: *mut OCSP_REQUEST) -> c_int;
 
     pub fn OCSP_response_create(status: c_int, bs: *mut OCSP_BASICRESP) -> *mut OCSP_RESPONSE;
 
@@ -115,4 +119,6 @@ extern "C" {
         st: *mut X509_STORE,
         flags: c_ulong,
     ) -> c_int;
+
+    pub fn OCSP_check_nonce(req: *mut OCSP_REQUEST, bs: *mut OCSP_BASICRESP) -> c_int;
 }

openssl/src/ocsp.rs

@@ -1,6 +1,9 @@
 use ffi;
 use foreign_types::ForeignTypeRef;
 use libc::{c_int, c_long, c_ulong};
+
+use std::error::Error;
+use std::fmt;
 use std::mem;
 use std::ptr;
 
@@ -28,6 +31,47 @@ bitflags! {
     }
 }
 
+#[derive(Debug)]
+pub enum OcspNonceCheckSuccessResult {
+    PresentAndEqual, // 1
+    Absent, // 2
+    PresentInResponseOnly, // 3
+}
+
+impl fmt::Display for OcspNonceCheckSuccessResult {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let message = match *self {
+            OcspNonceCheckSuccessResult::PresentAndEqual => "Nonces Present and Equal",
+            OcspNonceCheckSuccessResult::Absent => "Nonces Absent from Request and Response",
+            OcspNonceCheckSuccessResult::PresentInResponseOnly => "Nonce Present in Response Only",
+        };
+        write!(f, "{}", message)
+    }
+}
+
+#[derive(Debug)]
+pub enum OcspNonceCheckErrorResult {
+    PresentAndUnequal, // 0
+    PresentInRequestOnly, // -1
+    Unknown(ErrorStack), // any other return value
+}
+
+impl fmt::Display for OcspNonceCheckErrorResult {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            OcspNonceCheckErrorResult::PresentAndUnequal => write!(f, "Nonces Present and Unequal!"),
+            OcspNonceCheckErrorResult::PresentInRequestOnly => write!(f, "Nonce Present in Request Only!"),
+            OcspNonceCheckErrorResult::Unknown(ref err) => err.fmt(f),
+        }
+    }
+}
+
+impl Error for OcspNonceCheckErrorResult {
+    fn description(&self) -> &str {
+        "an error in OCSP nonce checking"
+    }
+}
+
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct OcspResponseStatus(c_int);
 
@@ -202,6 +246,24 @@ impl OcspBasicResponseRef {
             }
         }
     }
+
+    pub fn add_nonce(&mut self, val: Option<&[u8]>) -> Result<(), ErrorStack> {
+        unsafe {
+            let (ptr, len) = match val {
+                Some(slice) => (slice.as_ptr() as *mut _, slice.len() as c_int),
+                None => (ptr::null_mut(), 0),
+            };
+            cvt(ffi::OCSP_basic_add1_nonce(self.as_ptr(), ptr, len))?;
+            Ok(())
+        }
+    }
+
+    pub fn copy_nonce(&mut self, req: &OcspRequestRef) -> Result<(), ErrorStack> {
+        unsafe {
+            cvt(ffi::OCSP_copy_nonce(self.as_ptr(), req.as_ptr()))?;
+            Ok(())
+        }
+    }
 }
 
 foreign_type_and_impl_send_sync! {
@@ -340,6 +402,17 @@ impl OcspRequestRef {
             Ok(OcspOneReqRef::from_ptr_mut(ptr))
         }
     }
+
+    pub fn add_nonce(&mut self, val: Option<&[u8]>) -> Result<(), ErrorStack> {
+        unsafe {
+            let (ptr, len) = match val {
+                Some(slice) => (slice.as_ptr() as *mut _, slice.len() as c_int),
+                None => (ptr::null_mut(), 0),
+            };
+            cvt(ffi::OCSP_request_add1_nonce(self.as_ptr(), ptr, len))?;
+            Ok(())
+        }
+    }
 }
 
 foreign_type_and_impl_send_sync! {
@@ -349,3 +422,56 @@ foreign_type_and_impl_send_sync! {
     pub struct OcspOneReq;
     pub struct OcspOneReqRef;
 }
+
+pub fn check_nonce(req: &OcspRequestRef, bs: &OcspBasicResponseRef) -> Result<OcspNonceCheckSuccessResult, OcspNonceCheckErrorResult> {
+    unsafe {
+        match ffi::OCSP_check_nonce(req.as_ptr(), bs.as_ptr()) {
+            // good cases
+            1 => Ok(OcspNonceCheckSuccessResult::PresentAndEqual),
+            2 => Ok(OcspNonceCheckSuccessResult::Absent),
+            3 => Ok(OcspNonceCheckSuccessResult::PresentInResponseOnly),
+            // bad cases
+            0 => Err(OcspNonceCheckErrorResult::PresentAndUnequal),
+            -1 => Err(OcspNonceCheckErrorResult::PresentInRequestOnly),
+            _ => Err(OcspNonceCheckErrorResult::Unknown(ErrorStack::get())), //something else!
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use hex::FromHex;
+
+    use super::*;
+    use hash::MessageDigest;
+    use x509::X509;
+
+    #[test]
+    fn test_create_ocsp_request() {
+        let subject = include_bytes!("../test/cert.pem");
+        let subject = X509::from_pem(subject).unwrap();
+        let issuer = include_bytes!("../test/root-ca.pem");
+        let issuer = X509::from_pem(issuer).unwrap();
+
+        let req_der = include_bytes!("../test/ocsp-req.der");
+        let req_nonce_der = include_bytes!("../test/ocsp-req-nonce.der");
+
+        let cert_id = OcspCertId::from_cert(
+            MessageDigest::sha1(),
+            &subject,
+            &issuer
+            ).unwrap();
+
+        let mut req = OcspRequest::new().unwrap();
+        req.add_id(cert_id).unwrap();
+
+        assert_eq!(&*req.to_der().unwrap(), req_der.as_ref());
+
+
+        let nonce = Vec::from_hex("4413A2C5019A7C3A384CDD8AB30E3816").unwrap();
+        req.add_nonce(Some(&nonce)).unwrap();
+
+        assert_eq!(&*req.to_der().unwrap(), req_nonce_der.as_ref());
+    }
+
+}