Add stream panic propagation behind a nightly feature gate

5 files changed, 195 insertions, 12 deletions

diff --git a/openssl/Cargo.toml b/openssl/Cargo.toml
index 9c56623e..2dd9c32f 100644
--- a/openssl/Cargo.toml
+++ b/openssl/Cargo.toml
@@ -25,6 +25,8 @@ rfc5114 = ["openssl-sys/rfc5114"]
 ecdh_auto = ["openssl-sys-extras/ecdh_auto"]
 pkcs5_pbkdf2_hmac = ["openssl-sys/pkcs5_pbkdf2_hmac"]
 
+nightly = []
+
 [dependencies]
 bitflags = ">= 0.2, < 0.4"
 lazy_static = "0.1"
diff --git a/openssl/src/lib.rs b/openssl/src/lib.rs
index 88b67d97..54feab0d 100644
--- a/openssl/src/lib.rs
+++ b/openssl/src/lib.rs
@@ -1,4 +1,5 @@
 #![doc(html_root_url="https://sfackler.github.io/rust-openssl/doc/v0.7.4")]
+#![cfg_attr(feature = "nightly", feature(const_fn, recover, panic_propagate))]
 
 #[macro_use]
 extern crate bitflags;
diff --git a/openssl/src/ssl/bio.rs b/openssl/src/ssl/bio.rs
index a361ae81..aa445562 100644
--- a/openssl/src/ssl/bio.rs
+++ b/openssl/src/ssl/bio.rs
@@ -1,11 +1,12 @@
 use libc::{c_char, c_int, c_long, c_void, strlen};
 use ffi::{BIO, BIO_METHOD, BIO_CTRL_FLUSH, BIO_TYPE_NONE, BIO_new};
 use ffi_extras::{BIO_clear_retry_flags, BIO_set_retry_read, BIO_set_retry_write};
+use std::any::Any;
 use std::io;
 use std::io::prelude::*;
 use std::mem;
-use std::slice;
 use std::ptr;
+use std::slice;
 use std::sync::Arc;
 
 use ssl::error::SslError;
@@ -16,6 +17,7 @@ const NAME: [c_char; 5] = [114, 117, 115, 116, 0];
 pub struct StreamState<S> {
     pub stream: S,
     pub error: Option<io::Error>,
+    pub panic: Option<Box<Any + Send>>,
 }
 
 pub fn new<S: Read + Write>(stream: S) -> Result<(*mut BIO, Arc<BIO_METHOD>), SslError> {
@@ -35,6 +37,7 @@ pub fn new<S: Read + Write>(stream: S) -> Result<(*mut BIO, Arc<BIO_METHOD>), Ss
     let state = Box::new(StreamState {
         stream: stream,
         error: None,
+        panic: None,
     });
 
     unsafe {
@@ -51,6 +54,12 @@ pub unsafe fn take_error<S>(bio: *mut BIO) -> Option<io::Error> {
     state.error.take()
 }
 
+#[cfg_attr(not(feature = "nightly"), allow(dead_code))]
+pub unsafe fn take_panic<S>(bio: *mut BIO) -> Option<Box<Any + Send>> {
+    let state = state::<S>(bio);
+    state.panic.take()
+}
+
 pub unsafe fn get_ref<'a, S: 'a>(bio: *mut BIO) -> &'a S {
     let state: &'a StreamState<S> = mem::transmute((*bio).ptr);
     &state.stream
@@ -64,20 +73,69 @@ unsafe fn state<'a, S: 'a>(bio: *mut BIO) -> &'a mut StreamState<S> {
     mem::transmute((*bio).ptr)
 }
 
+#[cfg(feature = "nightly")]
+fn recover<F, T>(f: F) -> Result<T, Box<Any + Send>> where F: FnOnce() -> T + ::std::panic::RecoverSafe {
+    ::std::panic::recover(f)
+}
+
+#[cfg(not(feature = "nightly"))]
+fn recover<F, T>(f: F) -> Result<T, Box<Any + Send>> where F: FnOnce() -> T {
+    Ok(f())
+}
+
+#[cfg(feature = "nightly")]
+use std::panic::AssertRecoverSafe;
+
+#[cfg(not(feature = "nightly"))]
+struct AssertRecoverSafe<T>(T);
+
+#[cfg(not(feature = "nightly"))]
+impl<T> AssertRecoverSafe<T> {
+    fn new(t: T) -> Self {
+        AssertRecoverSafe(t)
+    }
+}
+
+#[cfg(not(feature = "nightly"))]
+impl<T> ::std::ops::Deref for AssertRecoverSafe<T> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        &self.0
+    }
+}
+
+#[cfg(not(feature = "nightly"))]
+impl<T> ::std::ops::DerefMut for AssertRecoverSafe<T> {
+    fn deref_mut(&mut self) -> &mut T {
+        &mut self.0
+    }
+}
+
 unsafe extern "C" fn bwrite<S: Write>(bio: *mut BIO, buf: *const c_char, len: c_int) -> c_int {
     BIO_clear_retry_flags(bio);
 
     let state = state::<S>(bio);
     let buf = slice::from_raw_parts(buf as *const _, len as usize);
-    match state.stream.write(buf) {
-        Ok(len) => len as c_int,
-        Err(err) => {
+
+    let result = {
+        let mut youre_not_my_supervisor = AssertRecoverSafe::new(&mut *state);
+        recover(move || youre_not_my_supervisor.stream.write(buf))
+    };
+
+    match result {
+        Ok(Ok(len)) => len as c_int,
+        Ok(Err(err)) => {
             if retriable_error(&err) {
                 BIO_set_retry_write(bio);
             }
             state.error = Some(err);
             -1
         }
+        Err(err) => {
+            state.panic = Some(err);
+            -1
+        }
     }
 }
 
@@ -86,15 +144,26 @@ unsafe extern "C" fn bread<S: Read>(bio: *mut BIO, buf: *mut c_char, len: c_int)
 
     let state = state::<S>(bio);
     let buf = slice::from_raw_parts_mut(buf as *mut _, len as usize);
-    match state.stream.read(buf) {
-        Ok(len) => len as c_int,
-        Err(err) => {
+
+    let result = {
+        let mut youre_not_my_supervisor = AssertRecoverSafe::new(&mut *state);
+        let mut fuuuu = AssertRecoverSafe::new(buf);
+        recover(move || youre_not_my_supervisor.stream.read(&mut *fuuuu))
+    };
+
+    match result {
+        Ok(Ok(len)) => len as c_int,
+        Ok(Err(err)) => {
             if retriable_error(&err) {
                 BIO_set_retry_read(bio);
             }
             state.error = Some(err);
             -1
         }
+        Err(err) => {
+            state.panic = Some(err);
+            -1
+        }
     }
 }
 
@@ -116,12 +185,21 @@ unsafe extern "C" fn ctrl<S: Write>(bio: *mut BIO,
                                     -> c_long {
     if cmd == BIO_CTRL_FLUSH {
         let state = state::<S>(bio);
-        match state.stream.flush() {
-            Ok(()) => 1,
-            Err(err) => {
+        let result = {
+            let mut youre_not_my_supervisor = AssertRecoverSafe::new(&mut *state);
+            recover(move || youre_not_my_supervisor.stream.flush())
+        };
+
+        match result {
+            Ok(Ok(())) => 1,
+            Ok(Err(err)) => {
                 state.error = Some(err);
                 0
             }
+            Err(err) => {
+                state.panic = Some(err);
+                0
+            }
         }
     } else {
         0
diff --git a/openssl/src/ssl/mod.rs b/openssl/src/ssl/mod.rs
index 955f10fd..9ea8a27b 100644
--- a/openssl/src/ssl/mod.rs
+++ b/openssl/src/ssl/mod.rs
@@ -26,8 +26,7 @@ use std::os::windows::io::{AsRawSocket, RawSocket};
 use ffi;
 use ffi_extras;
 use dh::DH;
-use ssl::error::{NonblockingSslError, SslError, StreamError, OpenSslErrors, OpenSslError,
-                 OpensslError};
+use ssl::error::{NonblockingSslError, SslError, OpenSslError, OpensslError};
 use x509::{X509StoreContext, X509FileType, X509};
 use crypto::pkey::PKey;
 
@@ -1137,6 +1136,8 @@ impl<S: Read + Write> SslStream<S> {
 
 impl<S> SslStream<S> {
     fn make_error(&mut self, ret: c_int) -> Error {
+        self.check_panic();
+
         match self.ssl.get_error(ret) {
             LibSslError::ErrorSsl => Error::Ssl(OpenSslError::get_stack()),
             LibSslError::ErrorSyscall => {
@@ -1163,6 +1164,8 @@ impl<S> SslStream<S> {
     }
 
     fn make_old_error(&mut self, ret: c_int) -> SslError {
+        self.check_panic();
+
         match self.ssl.get_error(ret) {
             LibSslError::ErrorSsl => SslError::get(),
             LibSslError::ErrorSyscall => {
@@ -1193,6 +1196,17 @@ impl<S> SslStream<S> {
         }
     }
 
+    #[cfg(feature = "nightly")]
+    fn check_panic(&mut self) {
+        if let Some(err) = unsafe { bio::take_panic::<S>(self.ssl.get_raw_rbio()) } {
+            ::std::panic::propagate(err)
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    fn check_panic(&mut self) {
+    }
+
     fn get_bio_error(&mut self) -> io::Error {
         let error = unsafe { bio::take_error::<S>(self.ssl.get_raw_rbio()) };
         match error {
diff --git a/openssl/src/ssl/tests/mod.rs b/openssl/src/ssl/tests/mod.rs
index af3c005e..7bd39170 100644
--- a/openssl/src/ssl/tests/mod.rs
+++ b/openssl/src/ssl/tests/mod.rs
@@ -957,3 +957,91 @@ fn broken_try_clone_doesnt_crash() {
     let stream1 = SslStream::connect(&context, inner).unwrap();
     let _stream2 = stream1.try_clone().unwrap();
 }
+
+#[test]
+#[should_panic(message = "blammo")]
+#[cfg(feature = "nightly")]
+fn write_panic() {
+    struct ExplodingStream(TcpStream);
+
+    impl Read for ExplodingStream {
+        fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+            self.0.read(buf)
+        }
+    }
+
+    impl Write for ExplodingStream {
+        fn write(&mut self, _: &[u8]) -> io::Result<usize> {
+            panic!("blammo");
+        }
+
+        fn flush(&mut self) -> io::Result<()> {
+            self.0.flush()
+        }
+    }
+
+    let (_s, stream) = Server::new();
+    let stream = ExplodingStream(stream);
+
+    let ctx = SslContext::new(SslMethod::Sslv23).unwrap();
+    let _ = SslStream::connect(&ctx, stream);
+}
+
+#[test]
+#[should_panic(message = "blammo")]
+#[cfg(feature = "nightly")]
+fn read_panic() {
+    struct ExplodingStream(TcpStream);
+
+    impl Read for ExplodingStream {
+        fn read(&mut self, _: &mut [u8]) -> io::Result<usize> {
+            panic!("blammo");
+        }
+    }
+
+    impl Write for ExplodingStream {
+        fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+            self.0.write(buf)
+        }
+
+        fn flush(&mut self) -> io::Result<()> {
+            self.0.flush()
+        }
+    }
+
+    let (_s, stream) = Server::new();
+    let stream = ExplodingStream(stream);
+
+    let ctx = SslContext::new(SslMethod::Sslv23).unwrap();
+    let _ = SslStream::connect(&ctx, stream);
+}
+
+#[test]
+#[should_panic(message = "blammo")]
+#[cfg(feature = "nightly")]
+fn flush_panic() {
+    struct ExplodingStream(TcpStream);
+
+    impl Read for ExplodingStream {
+        fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+            self.0.read(buf)
+        }
+    }
+
+    impl Write for ExplodingStream {
+        fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+            self.0.write(buf)
+        }
+
+        fn flush(&mut self) -> io::Result<()> {
+            panic!("blammo");
+        }
+    }
+
+    let (_s, stream) = Server::new();
+    let stream = ExplodingStream(stream);
+
+    let ctx = SslContext::new(SslMethod::Sslv23).unwrap();
+    let mut stream = SslStream::connect(&ctx, stream).unwrap();
+    let _ = stream.flush();
+}