From 6a7733af45493ddc1ededd2d0545004102c811a2 Mon Sep 17 00:00:00 2001 From: Daniel McCarney Date: Thu, 14 Nov 2024 13:38:14 -0500 Subject: [PATCH] crypto/pbkdf2: init package This commit imports the x/crypto/pbkdf2 package as described in the linked proposal. The code is unchanged with the exception of a few small updates to reflect feedback from the proposal comment period: * the Key function is made generic over a hash.Hash * the h function is moved to be the first argument * keyLen is renamed to keyLength * an error return is added * the unit tests were moved to the pbkdf2_test package Updates #69488 Change-Id: If72f854daeb65a5c7fbe45ebd341e63a33340624 Reviewed-on: https://go-review.googlesource.com/c/go/+/628135 Reviewed-by: Dmitri Shuralyov LUCI-TryBot-Result: Go LUCI Reviewed-by: Russ Cox --- api/next/69488.txt | 1 + doc/next/6-stdlib/2-pbkdf2.md | 2 + .../6-stdlib/99-minor/crypto/pbkdf2/69488.md | 1 + src/crypto/pbkdf2/pbkdf2.go | 77 ++++++++ src/crypto/pbkdf2/pbkdf2_test.go | 184 ++++++++++++++++++ src/go/build/deps_test.go | 2 + 6 files changed, 267 insertions(+) create mode 100644 api/next/69488.txt create mode 100644 doc/next/6-stdlib/2-pbkdf2.md create mode 100644 doc/next/6-stdlib/99-minor/crypto/pbkdf2/69488.md create mode 100644 src/crypto/pbkdf2/pbkdf2.go create mode 100644 src/crypto/pbkdf2/pbkdf2_test.go diff --git a/api/next/69488.txt b/api/next/69488.txt new file mode 100644 index 00000000000000..3eacc38bc450d2 --- /dev/null +++ b/api/next/69488.txt @@ -0,0 +1 @@ +pkg crypto/pbkdf2, func Key[$0 hash.Hash](func() $0, string, []uint8, int, int) ([]uint8, error) #69488 diff --git a/doc/next/6-stdlib/2-pbkdf2.md b/doc/next/6-stdlib/2-pbkdf2.md new file mode 100644 index 00000000000000..95a1a2c8515849 --- /dev/null +++ b/doc/next/6-stdlib/2-pbkdf2.md @@ -0,0 +1,2 @@ +A new pbkdf2 [Key] derivation function was added, based on the pre-existing +`golang.org/x/crypto/pbkdf2` package. diff --git a/doc/next/6-stdlib/99-minor/crypto/pbkdf2/69488.md b/doc/next/6-stdlib/99-minor/crypto/pbkdf2/69488.md new file mode 100644 index 00000000000000..6c36415b3cf12b --- /dev/null +++ b/doc/next/6-stdlib/99-minor/crypto/pbkdf2/69488.md @@ -0,0 +1 @@ + diff --git a/src/crypto/pbkdf2/pbkdf2.go b/src/crypto/pbkdf2/pbkdf2.go new file mode 100644 index 00000000000000..0887365388f18e --- /dev/null +++ b/src/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 ( + "crypto/hmac" + "hash" +) + +// Key derives a key from the password, salt and iteration count, returning a +// []byte of length keyLength 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(sha1.New, []byte("some password"), salt, 4096, 32) +// +// 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[Hash hash.Hash](h func() Hash, password string, salt []byte, iter, keyLength int) ([]byte, error) { + prf := hmac.New(func() hash.Hash { return h() }, []byte(password)) + hashLen := prf.Size() + numBlocks := (keyLength + 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[:keyLength], nil +} diff --git a/src/crypto/pbkdf2/pbkdf2_test.go b/src/crypto/pbkdf2/pbkdf2_test.go new file mode 100644 index 00000000000000..ecce26f8ba0798 --- /dev/null +++ b/src/crypto/pbkdf2/pbkdf2_test.go @@ -0,0 +1,184 @@ +// 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_test + +import ( + "bytes" + "crypto/pbkdf2" + "crypto/sha1" + "crypto/sha256" + "hash" + "testing" +) + +type testVector struct { + password string + salt string + iter int + output []byte +} + +// Test vectors from RFC 6070, http://tools.ietf.org/html/rfc6070 +var sha1TestVectors = []testVector{ + { + "password", + "salt", + 1, + []byte{ + 0x0c, 0x60, 0xc8, 0x0f, 0x96, 0x1f, 0x0e, 0x71, + 0xf3, 0xa9, 0xb5, 0x24, 0xaf, 0x60, 0x12, 0x06, + 0x2f, 0xe0, 0x37, 0xa6, + }, + }, + { + "password", + "salt", + 2, + []byte{ + 0xea, 0x6c, 0x01, 0x4d, 0xc7, 0x2d, 0x6f, 0x8c, + 0xcd, 0x1e, 0xd9, 0x2a, 0xce, 0x1d, 0x41, 0xf0, + 0xd8, 0xde, 0x89, 0x57, + }, + }, + { + "password", + "salt", + 4096, + []byte{ + 0x4b, 0x00, 0x79, 0x01, 0xb7, 0x65, 0x48, 0x9a, + 0xbe, 0xad, 0x49, 0xd9, 0x26, 0xf7, 0x21, 0xd0, + 0x65, 0xa4, 0x29, 0xc1, + }, + }, + // // This one takes too long + // { + // "password", + // "salt", + // 16777216, + // []byte{ + // 0xee, 0xfe, 0x3d, 0x61, 0xcd, 0x4d, 0xa4, 0xe4, + // 0xe9, 0x94, 0x5b, 0x3d, 0x6b, 0xa2, 0x15, 0x8c, + // 0x26, 0x34, 0xe9, 0x84, + // }, + // }, + { + "passwordPASSWORDpassword", + "saltSALTsaltSALTsaltSALTsaltSALTsalt", + 4096, + []byte{ + 0x3d, 0x2e, 0xec, 0x4f, 0xe4, 0x1c, 0x84, 0x9b, + 0x80, 0xc8, 0xd8, 0x36, 0x62, 0xc0, 0xe4, 0x4a, + 0x8b, 0x29, 0x1a, 0x96, 0x4c, 0xf2, 0xf0, 0x70, + 0x38, + }, + }, + { + "pass\000word", + "sa\000lt", + 4096, + []byte{ + 0x56, 0xfa, 0x6a, 0xa7, 0x55, 0x48, 0x09, 0x9d, + 0xcc, 0x37, 0xd7, 0xf0, 0x34, 0x25, 0xe0, 0xc3, + }, + }, +} + +// Test vectors from +// http://stackoverflow.com/questions/5130513/pbkdf2-hmac-sha2-test-vectors +var sha256TestVectors = []testVector{ + { + "password", + "salt", + 1, + []byte{ + 0x12, 0x0f, 0xb6, 0xcf, 0xfc, 0xf8, 0xb3, 0x2c, + 0x43, 0xe7, 0x22, 0x52, 0x56, 0xc4, 0xf8, 0x37, + 0xa8, 0x65, 0x48, 0xc9, + }, + }, + { + "password", + "salt", + 2, + []byte{ + 0xae, 0x4d, 0x0c, 0x95, 0xaf, 0x6b, 0x46, 0xd3, + 0x2d, 0x0a, 0xdf, 0xf9, 0x28, 0xf0, 0x6d, 0xd0, + 0x2a, 0x30, 0x3f, 0x8e, + }, + }, + { + "password", + "salt", + 4096, + []byte{ + 0xc5, 0xe4, 0x78, 0xd5, 0x92, 0x88, 0xc8, 0x41, + 0xaa, 0x53, 0x0d, 0xb6, 0x84, 0x5c, 0x4c, 0x8d, + 0x96, 0x28, 0x93, 0xa0, + }, + }, + { + "passwordPASSWORDpassword", + "saltSALTsaltSALTsaltSALTsaltSALTsalt", + 4096, + []byte{ + 0x34, 0x8c, 0x89, 0xdb, 0xcb, 0xd3, 0x2b, 0x2f, + 0x32, 0xd8, 0x14, 0xb8, 0x11, 0x6e, 0x84, 0xcf, + 0x2b, 0x17, 0x34, 0x7e, 0xbc, 0x18, 0x00, 0x18, + 0x1c, + }, + }, + { + "pass\000word", + "sa\000lt", + 4096, + []byte{ + 0x89, 0xb6, 0x9d, 0x05, 0x16, 0xf8, 0x29, 0x89, + 0x3c, 0x69, 0x62, 0x26, 0x65, 0x0a, 0x86, 0x87, + }, + }, +} + +func testHash(t *testing.T, h func() hash.Hash, hashName string, vectors []testVector) { + for i, v := range vectors { + o, err := pbkdf2.Key(h, v.password, []byte(v.salt), v.iter, len(v.output)) + if err != nil { + t.Error(err) + } + if !bytes.Equal(o, v.output) { + t.Errorf("%s %d: expected %x, got %x", hashName, i, v.output, o) + } + } +} + +func TestWithHMACSHA1(t *testing.T) { + testHash(t, sha1.New, "SHA1", sha1TestVectors) +} + +func TestWithHMACSHA256(t *testing.T) { + testHash(t, sha256.New, "SHA256", sha256TestVectors) +} + +var sink uint8 + +func benchmark(b *testing.B, h func() hash.Hash) { + var err error + password := make([]byte, h().Size()) + salt := make([]byte, 8) + for i := 0; i < b.N; i++ { + password, err = pbkdf2.Key(h, string(password), salt, 4096, len(password)) + if err != nil { + b.Error(err) + } + } + sink += password[0] +} + +func BenchmarkHMACSHA1(b *testing.B) { + benchmark(b, sha1.New) +} + +func BenchmarkHMACSHA256(b *testing.B) { + benchmark(b, sha256.New) +} diff --git a/src/go/build/deps_test.go b/src/go/build/deps_test.go index bbaedbfbd83d02..a4003442ae7e39 100644 --- a/src/go/build/deps_test.go +++ b/src/go/build/deps_test.go @@ -516,6 +516,8 @@ var depsRules = ` crypto/boring, crypto/internal/fips140/edwards25519/field < crypto/ecdh; + crypto/hmac < crypto/pbkdf2; + # Unfortunately, stuck with reflect via encoding/binary. encoding/binary, crypto/boring < golang.org/x/crypto/sha3;