5 files changed, 50 insertions, 5 deletions
diff --git a/libgo/go/crypto/rand/eagain.go b/libgo/go/crypto/rand/eagain.go
new file mode 100644
index 00000000000..2c853d0a134
--- /dev/null
+++ b/libgo/go/crypto/rand/eagain.go
@@ -0,0 +1,27 @@
+// Copyright 2014 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+
+package rand
+
+import (
+	"os"
+	"syscall"
+)
+
+func init() {
+	isEAGAIN = unixIsEAGAIN
+}
+
+// unixIsEAGAIN reports whether err is a syscall.EAGAIN wrapped in a PathError.
+// See golang.org/issue/9205
+func unixIsEAGAIN(err error) bool {
+	if pe, ok := err.(*os.PathError); ok {
+		if errno, ok := pe.Err.(syscall.Errno); ok && errno == syscall.EAGAIN {
+			return true
+		}
+	}
+	return false
+}
diff --git a/libgo/go/crypto/rand/rand.go b/libgo/go/crypto/rand/rand.go
index 4da3adb7010..ee32fa0bd67 100644
--- a/libgo/go/crypto/rand/rand.go
+++ b/libgo/go/crypto/rand/rand.go
@@ -10,7 +10,9 @@ import "io"
 
 // Reader is a global, shared instance of a cryptographically
 // strong pseudo-random generator.
+//
 // On Unix-like systems, Reader reads from /dev/urandom.
+// On Linux, Reader uses getrandom(2) if available, /dev/urandom otherwise.
 // On Windows systems, Reader uses the CryptGenRandom API.
 var Reader io.Reader
 
diff --git a/libgo/go/crypto/rand/rand_linux.go b/libgo/go/crypto/rand/rand_linux.go
index 8cb59c75dff..7d6d9e8a094 100644
--- a/libgo/go/crypto/rand/rand_linux.go
+++ b/libgo/go/crypto/rand/rand_linux.go
@@ -5,7 +5,7 @@
 package rand
 
 import (
-	"internal/syscall"
+	"internal/syscall/unix"
 	"sync"
 )
 
@@ -25,7 +25,7 @@ func pickStrategy() {
 	// - the machine has no entropy available (early boot + no hardware
 	//   entropy source?) and we want to avoid blocking later.
 	var buf [1]byte
-	n, err := syscall.GetRandom(buf[:], syscall.GRND_NONBLOCK)
+	n, err := unix.GetRandom(buf[:], unix.GRND_NONBLOCK)
 	useSyscall = n == 1 && err == nil
 }
 
@@ -34,6 +34,6 @@ func getRandomLinux(p []byte) (ok bool) {
 	if !useSyscall {
 		return false
 	}
-	n, err := syscall.GetRandom(p, 0)
+	n, err := unix.GetRandom(p, 0)
 	return n == len(p) && err == nil
 }
diff --git a/libgo/go/crypto/rand/rand_unix.go b/libgo/go/crypto/rand/rand_unix.go
index 62d0fbdb350..75c36e05b34 100644
--- a/libgo/go/crypto/rand/rand_unix.go
+++ b/libgo/go/crypto/rand/rand_unix.go
@@ -58,12 +58,28 @@ func (r *devReader) Read(b []byte) (n int, err error) {
 		if runtime.GOOS == "plan9" {
 			r.f = f
 		} else {
-			r.f = bufio.NewReader(f)
+			r.f = bufio.NewReader(hideAgainReader{f})
 		}
 	}
 	return r.f.Read(b)
 }
 
+var isEAGAIN func(error) bool // set by eagain.go on unix systems
+
+// hideAgainReader masks EAGAIN reads from /dev/urandom.
+// See golang.org/issue/9205
+type hideAgainReader struct {
+	r io.Reader
+}
+
+func (hr hideAgainReader) Read(p []byte) (n int, err error) {
+	n, err = hr.r.Read(p)
+	if err != nil && isEAGAIN != nil && isEAGAIN(err) {
+		err = nil
+	}
+	return
+}
+
 // Alternate pseudo-random implementation for use on
 // systems without a reliable /dev/urandom.
 
diff --git a/libgo/go/crypto/rand/util_test.go b/libgo/go/crypto/rand/util_test.go
index 1e2a4dd84b7..2f7cba8364a 100644
--- a/libgo/go/crypto/rand/util_test.go
+++ b/libgo/go/crypto/rand/util_test.go
@@ -10,7 +10,7 @@ import (
 	"testing"
 )
 
-// http://golang.org/issue/6849.
+// https://golang.org/issue/6849.
 func TestPrimeSmall(t *testing.T) {
 	for n := 2; n < 10; n++ {
 		p, err := rand.Prime(rand.Reader, n)