crypto/rand for Windows
R=rsc, brainman
CC=golang-dev
https://golang.org/cl/1773041
diff --git a/src/pkg/crypto/rand/Makefile b/src/pkg/crypto/rand/Makefile
index 0e7a553..2181259 100644
--- a/src/pkg/crypto/rand/Makefile
+++ b/src/pkg/crypto/rand/Makefile
@@ -9,4 +9,21 @@
GOFILES=\
rand.go\
+GOFILES_freebsd=\
+ rand_unix.go\
+
+GOFILES_darwin=\
+ rand_unix.go\
+
+GOFILES_linux=\
+ rand_unix.go\
+
+GOFILES_nacl=\
+ rand_unix.go\
+
+GOFILES_windows=\
+ rand_windows.go\
+
+GOFILES+=$(GOFILES_$(GOOS))
+
include ../../../Make.pkg
diff --git a/src/pkg/crypto/rand/rand.go b/src/pkg/crypto/rand/rand.go
index 01c3031..42d9da0 100644
--- a/src/pkg/crypto/rand/rand.go
+++ b/src/pkg/crypto/rand/rand.go
@@ -7,124 +7,15 @@
package rand
import (
- "crypto/aes"
"io"
"os"
- "sync"
- "time"
)
// Reader is a global, shared instance of a cryptographically
// strong pseudo-random generator.
+// On Unix-like systems, Reader reads from /dev/urandom.
+// On Windows systems, Reader uses the CryptGenRandom API.
var Reader io.Reader
// Read is a helper function that calls Reader.Read.
func Read(b []byte) (n int, err os.Error) { return Reader.Read(b) }
-
-// Easy implementation: read from /dev/urandom.
-// This is sufficient on Linux, OS X, and FreeBSD.
-
-func init() { Reader = &devReader{name: "/dev/urandom"} }
-
-// A devReader satisfies reads by reading the file named name.
-type devReader struct {
- name string
- f *os.File
- mu sync.Mutex
-}
-
-func (r *devReader) Read(b []byte) (n int, err os.Error) {
- r.mu.Lock()
- if r.f == nil {
- f, err := os.Open(r.name, os.O_RDONLY, 0)
- if f == nil {
- return 0, err
- }
- r.f = f
- }
- r.mu.Unlock()
- return r.f.Read(b)
-}
-
-// Alternate pseudo-random implementation for use on
-// systems without a reliable /dev/urandom. So far we
-// haven't needed it.
-
-// newReader returns a new pseudorandom generator that
-// seeds itself by reading from entropy. If entropy == nil,
-// the generator seeds itself by reading from the system's
-// random number generator, typically /dev/random.
-// The Read method on the returned reader always returns
-// the full amount asked for, or else it returns an error.
-//
-// The generator uses the X9.31 algorithm with AES-128,
-// reseeding after every 1 MB of generated data.
-func newReader(entropy io.Reader) io.Reader {
- if entropy == nil {
- entropy = &devReader{name: "/dev/random"}
- }
- return &reader{entropy: entropy}
-}
-
-type reader struct {
- mu sync.Mutex
- budget int // number of bytes that can be generated
- cipher *aes.Cipher
- entropy io.Reader
- time, seed, dst, key [aes.BlockSize]byte
-}
-
-func (r *reader) Read(b []byte) (n int, err os.Error) {
- r.mu.Lock()
- defer r.mu.Unlock()
- n = len(b)
-
- for len(b) > 0 {
- if r.budget == 0 {
- _, err := io.ReadFull(r.entropy, r.seed[0:])
- if err != nil {
- return n - len(b), err
- }
- _, err = io.ReadFull(r.entropy, r.key[0:])
- if err != nil {
- return n - len(b), err
- }
- r.cipher, err = aes.NewCipher(r.key[0:])
- if err != nil {
- return n - len(b), err
- }
- r.budget = 1 << 20 // reseed after generating 1MB
- }
- r.budget -= aes.BlockSize
-
- // ANSI X9.31 (== X9.17) algorithm, but using AES in place of 3DES.
- //
- // single block:
- // t = encrypt(time)
- // dst = encrypt(t^seed)
- // seed = encrypt(t^dst)
- ns := time.Nanoseconds()
- r.time[0] = byte(ns >> 56)
- r.time[1] = byte(ns >> 48)
- r.time[2] = byte(ns >> 40)
- r.time[3] = byte(ns >> 32)
- r.time[4] = byte(ns >> 24)
- r.time[5] = byte(ns >> 16)
- r.time[6] = byte(ns >> 8)
- r.time[7] = byte(ns)
- r.cipher.Encrypt(r.time[0:], r.time[0:])
- for i := 0; i < aes.BlockSize; i++ {
- r.dst[i] = r.time[i] ^ r.seed[i]
- }
- r.cipher.Encrypt(r.dst[0:], r.dst[0:])
- for i := 0; i < aes.BlockSize; i++ {
- r.seed[i] = r.time[i] ^ r.dst[i]
- }
- r.cipher.Encrypt(r.seed[0:], r.seed[0:])
-
- m := copy(b, r.dst[0:])
- b = b[m:]
- }
-
- return n, nil
-}
diff --git a/src/pkg/crypto/rand/rand_unix.go b/src/pkg/crypto/rand/rand_unix.go
new file mode 100644
index 0000000..d8db6f2
--- /dev/null
+++ b/src/pkg/crypto/rand/rand_unix.go
@@ -0,0 +1,124 @@
+// Copyright 2010 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.
+
+// Unix cryptographically secure pseudorandom number
+// generator.
+
+package rand
+
+import (
+ "crypto/aes"
+ "io"
+ "os"
+ "sync"
+ "time"
+)
+
+// Easy implementation: read from /dev/urandom.
+// This is sufficient on Linux, OS X, and FreeBSD.
+
+func init() { Reader = &devReader{name: "/dev/urandom"} }
+
+// A devReader satisfies reads by reading the file named name.
+type devReader struct {
+ name string
+ f *os.File
+ mu sync.Mutex
+}
+
+func (r *devReader) Read(b []byte) (n int, err os.Error) {
+ r.mu.Lock()
+ if r.f == nil {
+ f, err := os.Open(r.name, os.O_RDONLY, 0)
+ if f == nil {
+ return 0, err
+ }
+ r.f = f
+ }
+ r.mu.Unlock()
+ return r.f.Read(b)
+}
+
+// Alternate pseudo-random implementation for use on
+// systems without a reliable /dev/urandom. So far we
+// haven't needed it.
+
+// newReader returns a new pseudorandom generator that
+// seeds itself by reading from entropy. If entropy == nil,
+// the generator seeds itself by reading from the system's
+// random number generator, typically /dev/random.
+// The Read method on the returned reader always returns
+// the full amount asked for, or else it returns an error.
+//
+// The generator uses the X9.31 algorithm with AES-128,
+// reseeding after every 1 MB of generated data.
+func newReader(entropy io.Reader) io.Reader {
+ if entropy == nil {
+ entropy = &devReader{name: "/dev/random"}
+ }
+ return &reader{entropy: entropy}
+}
+
+type reader struct {
+ mu sync.Mutex
+ budget int // number of bytes that can be generated
+ cipher *aes.Cipher
+ entropy io.Reader
+ time, seed, dst, key [aes.BlockSize]byte
+}
+
+func (r *reader) Read(b []byte) (n int, err os.Error) {
+ r.mu.Lock()
+ defer r.mu.Unlock()
+ n = len(b)
+
+ for len(b) > 0 {
+ if r.budget == 0 {
+ _, err := io.ReadFull(r.entropy, r.seed[0:])
+ if err != nil {
+ return n - len(b), err
+ }
+ _, err = io.ReadFull(r.entropy, r.key[0:])
+ if err != nil {
+ return n - len(b), err
+ }
+ r.cipher, err = aes.NewCipher(r.key[0:])
+ if err != nil {
+ return n - len(b), err
+ }
+ r.budget = 1 << 20 // reseed after generating 1MB
+ }
+ r.budget -= aes.BlockSize
+
+ // ANSI X9.31 (== X9.17) algorithm, but using AES in place of 3DES.
+ //
+ // single block:
+ // t = encrypt(time)
+ // dst = encrypt(t^seed)
+ // seed = encrypt(t^dst)
+ ns := time.Nanoseconds()
+ r.time[0] = byte(ns >> 56)
+ r.time[1] = byte(ns >> 48)
+ r.time[2] = byte(ns >> 40)
+ r.time[3] = byte(ns >> 32)
+ r.time[4] = byte(ns >> 24)
+ r.time[5] = byte(ns >> 16)
+ r.time[6] = byte(ns >> 8)
+ r.time[7] = byte(ns)
+ r.cipher.Encrypt(r.time[0:], r.time[0:])
+ for i := 0; i < aes.BlockSize; i++ {
+ r.dst[i] = r.time[i] ^ r.seed[i]
+ }
+ r.cipher.Encrypt(r.dst[0:], r.dst[0:])
+ for i := 0; i < aes.BlockSize; i++ {
+ r.seed[i] = r.time[i] ^ r.dst[i]
+ }
+ r.cipher.Encrypt(r.seed[0:], r.seed[0:])
+
+ m := copy(b, r.dst[0:])
+ b = b[m:]
+ }
+
+ return n, nil
+}
diff --git a/src/pkg/crypto/rand/rand_windows.go b/src/pkg/crypto/rand/rand_windows.go
new file mode 100755
index 0000000..9bab2cb
--- /dev/null
+++ b/src/pkg/crypto/rand/rand_windows.go
@@ -0,0 +1,42 @@
+// Copyright 2010 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.
+
+// Windows cryptographically secure pseudorandom number
+// generator.
+
+package rand
+
+import (
+ "os"
+ "sync"
+ "syscall"
+)
+
+// Implemented by using Windows CryptoAPI 2.0.
+
+func init() { Reader = &rngReader{} }
+
+// A rngReader satisfies reads by reading from the Windows CryptGenRandom API.
+type rngReader struct {
+ prov uint32
+ mu sync.Mutex
+}
+
+func (r *rngReader) Read(b []byte) (n int, err os.Error) {
+ r.mu.Lock()
+ if r.prov == 0 {
+ const provType = syscall.PROV_RSA_FULL
+ const flags = syscall.CRYPT_VERIFYCONTEXT | syscall.CRYPT_SILENT
+ ok, errno := syscall.CryptAcquireContext(&r.prov, nil, nil, provType, flags)
+ if !ok {
+ return 0, os.NewSyscallError("CryptAcquireContext", errno)
+ }
+ }
+ r.mu.Unlock()
+ ok, errno := syscall.CryptGenRandom(r.prov, uint32(len(b)), &b[0])
+ if !ok {
+ return 0, os.NewSyscallError("CryptGenRandom", errno)
+ }
+ return len(b), nil
+}
