Don't use custom PBKDF2 function (#382)

4 files changed, 85 insertions, 42 deletions

diff --git a/models/user.go b/models/user.go
index 40afc48491..a9a7ba5948 100644
--- a/models/user.go
+++ b/models/user.go
@@ -25,6 +25,7 @@ import (
 	"github.com/Unknwon/com"
 	"github.com/go-xorm/xorm"
 	"github.com/nfnt/resize"
+	"golang.org/x/crypto/pbkdf2"
 
 	"code.gitea.io/git"
 	api "code.gitea.io/sdk/gitea"
@@ -361,7 +362,7 @@ func (u *User) NewGitSig() *git.Signature {
 
 // EncodePasswd encodes password to safe format.
 func (u *User) EncodePasswd() {
-	newPasswd := base.PBKDF2([]byte(u.Passwd), []byte(u.Salt), 10000, 50, sha256.New)
+	newPasswd := pbkdf2.Key([]byte(u.Passwd), []byte(u.Salt), 10000, 50, sha256.New)
 	u.Passwd = fmt.Sprintf("%x", newPasswd)
 }
 
diff --git a/modules/base/tool.go b/modules/base/tool.go
index 981f89b6a5..e41d1ca468 100644
--- a/modules/base/tool.go
+++ b/modules/base/tool.go
@@ -5,14 +5,12 @@
 package base
 
 import (
-	"crypto/hmac"
 	"crypto/md5"
 	"crypto/rand"
 	"crypto/sha1"
 	"encoding/base64"
 	"encoding/hex"
 	"fmt"
-	"hash"
 	"html/template"
 	"math"
 	"net/http"
@@ -97,45 +95,6 @@ func GetRandomString(n int, alphabets ...byte) string {
 	return string(bytes)
 }
 
-// PBKDF2 http://code.google.com/p/go/source/browse/pbkdf2/pbkdf2.go?repo=crypto
-// FIXME: use https://godoc.org/golang.org/x/crypto/pbkdf2?
-func PBKDF2(password, salt []byte, iter, keyLen int, h func() hash.Hash) []byte {
-	prf := hmac.New(h, password)
-	hashLen := prf.Size()
-	numBlocks := (keyLen + hashLen - 1) / hashLen
-
-	var buf [4]byte
-	dk := make([]byte, 0, numBlocks*hashLen)
-	U := make([]byte, hashLen)
-	for block := 1; block <= numBlocks; block++ {
-		// N.B.: || means concatenation, ^ means XOR
-		// for each block T_i = U_1 ^ U_2 ^ ... ^ U_iter
-		// U_1 = PRF(password, salt || uint(i))
-		prf.Reset()
-		prf.Write(salt)
-		buf[0] = byte(block >> 24)
-		buf[1] = byte(block >> 16)
-		buf[2] = byte(block >> 8)
-		buf[3] = byte(block)
-		prf.Write(buf[:4])
-		dk = prf.Sum(dk)
-		T := dk[len(dk)-hashLen:]
-		copy(U, T)
-
-		// U_n = PRF(password, U_(n-1))
-		for n := 2; n <= iter; n++ {
-			prf.Reset()
-			prf.Write(U)
-			U = U[:0]
-			U = prf.Sum(U)
-			for x := range U {
-				T[x] ^= U[x]
-			}
-		}
-	}
-	return dk[:keyLen]
-}
-
 // VerifyTimeLimitCode verify time limit code
 func VerifyTimeLimitCode(data string, minutes int, code string) bool {
 	if len(code) <= 18 {
diff --git a/vendor/golang.org/x/crypto/pbkdf2/pbkdf2.go b/vendor/golang.org/x/crypto/pbkdf2/pbkdf2.go
new file mode 100644
index 0000000000..593f653008
--- /dev/null
+++ b/vendor/golang.org/x/crypto/pbkdf2/pbkdf2.go
@@ -0,0 +1,77 @@
+// Copyright 2012 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.
+
+/*
+Package pbkdf2 implements the key derivation function PBKDF2 as defined in RFC
+2898 / PKCS #5 v2.0.
+
+A key derivation function is useful when encrypting data based on a password
+or any other not-fully-random data. It uses a pseudorandom function to derive
+a secure encryption key based on the password.
+
+While v2.0 of the standard defines only one pseudorandom function to use,
+HMAC-SHA1, the drafted v2.1 specification allows use of all five FIPS Approved
+Hash Functions SHA-1, SHA-224, SHA-256, SHA-384 and SHA-512 for HMAC. To
+choose, you can pass the `New` functions from the different SHA packages to
+pbkdf2.Key.
+*/
+package pbkdf2 // import "golang.org/x/crypto/pbkdf2"
+
+import (
+	"crypto/hmac"
+	"hash"
+)
+
+// Key derives a key from the password, salt and iteration count, returning a
+// []byte of length keylen that can be used as cryptographic key. The key is
+// derived based on the method described as PBKDF2 with the HMAC variant using
+// the supplied hash function.
+//
+// For example, to use a HMAC-SHA-1 based PBKDF2 key derivation function, you
+// can get a derived key for e.g. AES-256 (which needs a 32-byte key) by
+// doing:
+//
+// 	dk := pbkdf2.Key([]byte("some password"), salt, 4096, 32, sha1.New)
+//
+// Remember to get a good random salt. At least 8 bytes is recommended by the
+// RFC.
+//
+// Using a higher iteration count will increase the cost of an exhaustive
+// search but will also make derivation proportionally slower.
+func Key(password, salt []byte, iter, keyLen int, h func() hash.Hash) []byte {
+	prf := hmac.New(h, password)
+	hashLen := prf.Size()
+	numBlocks := (keyLen + hashLen - 1) / hashLen
+
+	var buf [4]byte
+	dk := make([]byte, 0, numBlocks*hashLen)
+	U := make([]byte, hashLen)
+	for block := 1; block <= numBlocks; block++ {
+		// N.B.: || means concatenation, ^ means XOR
+		// for each block T_i = U_1 ^ U_2 ^ ... ^ U_iter
+		// U_1 = PRF(password, salt || uint(i))
+		prf.Reset()
+		prf.Write(salt)
+		buf[0] = byte(block >> 24)
+		buf[1] = byte(block >> 16)
+		buf[2] = byte(block >> 8)
+		buf[3] = byte(block)
+		prf.Write(buf[:4])
+		dk = prf.Sum(dk)
+		T := dk[len(dk)-hashLen:]
+		copy(U, T)
+
+		// U_n = PRF(password, U_(n-1))
+		for n := 2; n <= iter; n++ {
+			prf.Reset()
+			prf.Write(U)
+			U = U[:0]
+			U = prf.Sum(U)
+			for x := range U {
+				T[x] ^= U[x]
+			}
+		}
+	}
+	return dk[:keyLen]
+}
diff --git a/vendor/vendor.json b/vendor/vendor.json
index 1c1b0acdf8..50447e4bf2 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -873,6 +873,12 @@
 			"revisionTime": "2016-10-31T15:37:30Z"
 		},
 		{
+			"checksumSHA1": "1MGpGDQqnUoRpv7VEcQrXOBydXE=",
+			"path": "golang.org/x/crypto/pbkdf2",
+			"revision": "8e06e8ddd9629eb88639aba897641bff8031f1d3",
+			"revisionTime": "2016-09-10T18:59:01Z"
+		},
+		{
 			"checksumSHA1": "LlElMHeTC34ng8eHzjvtUhAgrr8=",
 			"path": "golang.org/x/crypto/ssh",
 			"revision": "9477e0b78b9ac3d0b03822fd95422e2fe07627cd",