From: Aleks Rudzitis Date: Thu, 21 Jul 2022 18:19:42 +0000 (-0700) Subject: crypto: allow hash.Hash for OAEP and MGF1 to be specified independently X-Git-Tag: go1.20rc1~342 X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=e48fc2665e2e95eddea612fa315403d50c7beb2b;p=gostls13.git crypto: allow hash.Hash for OAEP and MGF1 to be specified independently crypto/rsa assumes RSA OAEP uses the same hash to be used for both the label and the mask generation function. However, implementations in other languages, such as Java and Python, allow these parameters to be specified independently. This change allows the MGF hash to be specified independently for decrypt operations in order to allow decrypting ciphertexts generated in other environments. Fixes: #19974 Change-Id: If453d628f0da354ceb3b52863f30087471670f7b Reviewed-on: https://go-review.googlesource.com/c/go/+/418874 Auto-Submit: Andrew Bonventre TryBot-Result: Gopher Robot Reviewed-by: Russ Cox Reviewed-by: Robert Griesemer Reviewed-by: Andrew Bonventre Run-TryBot: Andrew Bonventre --- diff --git a/api/next/19974.txt b/api/next/19974.txt new file mode 100644 index 0000000000..22893facba --- /dev/null +++ b/api/next/19974.txt @@ -0,0 +1 @@ +pkg crypto/rsa, type OAEPOptions struct, MGFHash crypto.Hash #19974 diff --git a/src/crypto/internal/boring/notboring.go b/src/crypto/internal/boring/notboring.go index e8eb76e1bb..2fa5eaf30f 100644 --- a/src/crypto/internal/boring/notboring.go +++ b/src/crypto/internal/boring/notboring.go @@ -73,7 +73,7 @@ func VerifyECDSA(pub *PublicKeyECDSA, hash []byte, sig []byte) bool { type PublicKeyRSA struct{ _ int } type PrivateKeyRSA struct{ _ int } -func DecryptRSAOAEP(h hash.Hash, priv *PrivateKeyRSA, ciphertext, label []byte) ([]byte, error) { +func DecryptRSAOAEP(h, mgfHash hash.Hash, priv *PrivateKeyRSA, ciphertext, label []byte) ([]byte, error) { panic("boringcrypto: not available") } func DecryptRSAPKCS1(priv *PrivateKeyRSA, ciphertext []byte) ([]byte, error) { @@ -82,7 +82,7 @@ func DecryptRSAPKCS1(priv *PrivateKeyRSA, ciphertext []byte) ([]byte, error) { func DecryptRSANoPadding(priv *PrivateKeyRSA, ciphertext []byte) ([]byte, error) { panic("boringcrypto: not available") } -func EncryptRSAOAEP(h hash.Hash, pub *PublicKeyRSA, msg, label []byte) ([]byte, error) { +func EncryptRSAOAEP(h, mgfHash hash.Hash, pub *PublicKeyRSA, msg, label []byte) ([]byte, error) { panic("boringcrypto: not available") } func EncryptRSAPKCS1(pub *PublicKeyRSA, msg []byte) ([]byte, error) { diff --git a/src/crypto/internal/boring/rsa.go b/src/crypto/internal/boring/rsa.go index a1f85591a7..fa693ea319 100644 --- a/src/crypto/internal/boring/rsa.go +++ b/src/crypto/internal/boring/rsa.go @@ -109,7 +109,7 @@ func (k *PrivateKeyRSA) withKey(f func(*C.GO_RSA) C.int) C.int { } func setupRSA(withKey func(func(*C.GO_RSA) C.int) C.int, - padding C.int, h hash.Hash, label []byte, saltLen int, ch crypto.Hash, + padding C.int, h, mgfHash hash.Hash, label []byte, saltLen int, ch crypto.Hash, init func(*C.GO_EVP_PKEY_CTX) C.int) (pkey *C.GO_EVP_PKEY, ctx *C.GO_EVP_PKEY_CTX, err error) { defer func() { if err != nil { @@ -148,9 +148,16 @@ func setupRSA(withKey func(func(*C.GO_RSA) C.int) C.int, if md == nil { return nil, nil, errors.New("crypto/rsa: unsupported hash function") } + mgfMD := hashToMD(mgfHash) + if mgfMD == nil { + return nil, nil, errors.New("crypto/rsa: unsupported hash function") + } if C._goboringcrypto_EVP_PKEY_CTX_set_rsa_oaep_md(ctx, md) == 0 { return nil, nil, fail("EVP_PKEY_set_rsa_oaep_md") } + if C._goboringcrypto_EVP_PKEY_CTX_set_rsa_mgf1_md(ctx, mgfMD) == 0 { + return nil, nil, fail("EVP_PKEY_set_rsa_mgf1_md") + } // ctx takes ownership of label, so malloc a copy for BoringCrypto to free. clabel := (*C.uint8_t)(C._goboringcrypto_OPENSSL_malloc(C.size_t(len(label)))) if clabel == nil { @@ -180,12 +187,12 @@ func setupRSA(withKey func(func(*C.GO_RSA) C.int) C.int, } func cryptRSA(withKey func(func(*C.GO_RSA) C.int) C.int, - padding C.int, h hash.Hash, label []byte, saltLen int, ch crypto.Hash, + padding C.int, h, mgfHash hash.Hash, label []byte, saltLen int, ch crypto.Hash, init func(*C.GO_EVP_PKEY_CTX) C.int, crypt func(*C.GO_EVP_PKEY_CTX, *C.uint8_t, *C.size_t, *C.uint8_t, C.size_t) C.int, in []byte) ([]byte, error) { - pkey, ctx, err := setupRSA(withKey, padding, h, label, saltLen, ch, init) + pkey, ctx, err := setupRSA(withKey, padding, h, mgfHash, label, saltLen, ch, init) if err != nil { return nil, err } @@ -203,28 +210,28 @@ func cryptRSA(withKey func(func(*C.GO_RSA) C.int) C.int, return out[:outLen], nil } -func DecryptRSAOAEP(h hash.Hash, priv *PrivateKeyRSA, ciphertext, label []byte) ([]byte, error) { - return cryptRSA(priv.withKey, C.GO_RSA_PKCS1_OAEP_PADDING, h, label, 0, 0, decryptInit, decrypt, ciphertext) +func DecryptRSAOAEP(h, mgfHash hash.Hash, priv *PrivateKeyRSA, ciphertext, label []byte) ([]byte, error) { + return cryptRSA(priv.withKey, C.GO_RSA_PKCS1_OAEP_PADDING, h, mgfHash, label, 0, 0, decryptInit, decrypt, ciphertext) } -func EncryptRSAOAEP(h hash.Hash, pub *PublicKeyRSA, msg, label []byte) ([]byte, error) { - return cryptRSA(pub.withKey, C.GO_RSA_PKCS1_OAEP_PADDING, h, label, 0, 0, encryptInit, encrypt, msg) +func EncryptRSAOAEP(h, mgfHash hash.Hash, pub *PublicKeyRSA, msg, label []byte) ([]byte, error) { + return cryptRSA(pub.withKey, C.GO_RSA_PKCS1_OAEP_PADDING, h, mgfHash, label, 0, 0, encryptInit, encrypt, msg) } func DecryptRSAPKCS1(priv *PrivateKeyRSA, ciphertext []byte) ([]byte, error) { - return cryptRSA(priv.withKey, C.GO_RSA_PKCS1_PADDING, nil, nil, 0, 0, decryptInit, decrypt, ciphertext) + return cryptRSA(priv.withKey, C.GO_RSA_PKCS1_PADDING, nil, nil, nil, 0, 0, decryptInit, decrypt, ciphertext) } func EncryptRSAPKCS1(pub *PublicKeyRSA, msg []byte) ([]byte, error) { - return cryptRSA(pub.withKey, C.GO_RSA_PKCS1_PADDING, nil, nil, 0, 0, encryptInit, encrypt, msg) + return cryptRSA(pub.withKey, C.GO_RSA_PKCS1_PADDING, nil, nil, nil, 0, 0, encryptInit, encrypt, msg) } func DecryptRSANoPadding(priv *PrivateKeyRSA, ciphertext []byte) ([]byte, error) { - return cryptRSA(priv.withKey, C.GO_RSA_NO_PADDING, nil, nil, 0, 0, decryptInit, decrypt, ciphertext) + return cryptRSA(priv.withKey, C.GO_RSA_NO_PADDING, nil, nil, nil, 0, 0, decryptInit, decrypt, ciphertext) } func EncryptRSANoPadding(pub *PublicKeyRSA, msg []byte) ([]byte, error) { - return cryptRSA(pub.withKey, C.GO_RSA_NO_PADDING, nil, nil, 0, 0, encryptInit, encrypt, msg) + return cryptRSA(pub.withKey, C.GO_RSA_NO_PADDING, nil, nil, nil, 0, 0, encryptInit, encrypt, msg) } // These dumb wrappers work around the fact that cgo functions cannot be used as values directly. diff --git a/src/crypto/rsa/rsa.go b/src/crypto/rsa/rsa.go index c941124fb2..9c57595dd1 100644 --- a/src/crypto/rsa/rsa.go +++ b/src/crypto/rsa/rsa.go @@ -68,6 +68,11 @@ func (pub *PublicKey) Equal(x crypto.PublicKey) bool { type OAEPOptions struct { // Hash is the hash function that will be used when generating the mask. Hash crypto.Hash + + // MGFHash is the hash function used for MGF1. + // If zero, Hash is used instead. + MGFHash crypto.Hash + // Label is an arbitrary byte string that must be equal to the value // used when encrypting. Label []byte @@ -160,7 +165,11 @@ func (priv *PrivateKey) Decrypt(rand io.Reader, ciphertext []byte, opts crypto.D switch opts := opts.(type) { case *OAEPOptions: - return DecryptOAEP(opts.Hash.New(), rand, priv, ciphertext, opts.Label) + if opts.MGFHash == 0 { + return decryptOAEP(opts.Hash.New(), opts.Hash.New(), rand, priv, ciphertext, opts.Label) + } else { + return decryptOAEP(opts.Hash.New(), opts.MGFHash.New(), rand, priv, ciphertext, opts.Label) + } case *PKCS1v15DecryptOptions: if l := opts.SessionKeyLen; l > 0 { @@ -458,7 +467,7 @@ func EncryptOAEP(hash hash.Hash, random io.Reader, pub *PublicKey, msg []byte, l if err != nil { return nil, err } - return boring.EncryptRSAOAEP(hash, bkey, msg, label) + return boring.EncryptRSAOAEP(hash, hash, bkey, msg, label) } boring.UnreachableExceptTests() @@ -651,6 +660,10 @@ func decryptAndCheck(random io.Reader, priv *PrivateKey, c *big.Int) (m *big.Int // The label parameter must match the value given when encrypting. See // EncryptOAEP for details. func DecryptOAEP(hash hash.Hash, random io.Reader, priv *PrivateKey, ciphertext []byte, label []byte) ([]byte, error) { + return decryptOAEP(hash, hash, random, priv, ciphertext, label) +} + +func decryptOAEP(hash, mgfHash hash.Hash, random io.Reader, priv *PrivateKey, ciphertext []byte, label []byte) ([]byte, error) { if err := checkPub(&priv.PublicKey); err != nil { return nil, err } @@ -665,7 +678,7 @@ func DecryptOAEP(hash hash.Hash, random io.Reader, priv *PrivateKey, ciphertext if err != nil { return nil, err } - out, err := boring.DecryptRSAOAEP(hash, bkey, ciphertext, label) + out, err := boring.DecryptRSAOAEP(hash, mgfHash, bkey, ciphertext, label) if err != nil { return nil, ErrDecryption } @@ -691,8 +704,8 @@ func DecryptOAEP(hash hash.Hash, random io.Reader, priv *PrivateKey, ciphertext seed := em[1 : hash.Size()+1] db := em[hash.Size()+1:] - mgf1XOR(seed, hash, db) - mgf1XOR(db, hash, seed) + mgf1XOR(seed, mgfHash, db) + mgf1XOR(db, mgfHash, seed) lHash2 := db[0:hash.Size()] diff --git a/src/crypto/rsa/rsa_test.go b/src/crypto/rsa/rsa_test.go index 766d9a954f..99b2cf5ae8 100644 --- a/src/crypto/rsa/rsa_test.go +++ b/src/crypto/rsa/rsa_test.go @@ -7,6 +7,7 @@ package rsa import ( "bytes" "crypto" + "crypto/internal/boring" "crypto/rand" "crypto/sha1" "crypto/sha256" @@ -15,8 +16,6 @@ import ( "testing" ) -import "crypto/internal/boring" - func TestKeyGeneration(t *testing.T) { for _, size := range []int{128, 1024, 2048, 3072} { priv, err := GenerateKey(rand.Reader, size) @@ -303,6 +302,31 @@ func TestDecryptOAEP(t *testing.T) { } } +func Test2DecryptOAEP(t *testing.T) { + random := rand.Reader + + msg := []byte{0xed, 0x36, 0x90, 0x8d, 0xbe, 0xfc, 0x35, 0x40, 0x70, 0x4f, 0xf5, 0x9d, 0x6e, 0xc2, 0xeb, 0xf5, 0x27, 0xae, 0x65, 0xb0, 0x59, 0x29, 0x45, 0x25, 0x8c, 0xc1, 0x91, 0x22} + in := []byte{0x72, 0x26, 0x84, 0xc9, 0xcf, 0xd6, 0xa8, 0x96, 0x04, 0x3e, 0x34, 0x07, 0x2c, 0x4f, 0xe6, 0x52, 0xbe, 0x46, 0x3c, 0xcf, 0x79, 0x21, 0x09, 0x64, 0xe7, 0x33, 0x66, 0x9b, 0xf8, 0x14, 0x22, 0x43, 0xfe, 0x8e, 0x52, 0x8b, 0xe0, 0x5f, 0x98, 0xef, 0x54, 0xac, 0x6b, 0xc6, 0x26, 0xac, 0x5b, 0x1b, 0x4b, 0x7d, 0x2e, 0xd7, 0x69, 0x28, 0x5a, 0x2f, 0x4a, 0x95, 0x89, 0x6c, 0xc7, 0x53, 0x95, 0xc7, 0xd2, 0x89, 0x04, 0x6f, 0x94, 0x74, 0x9b, 0x09, 0x0d, 0xf4, 0x61, 0x2e, 0xab, 0x48, 0x57, 0x4a, 0xbf, 0x95, 0xcb, 0xff, 0x15, 0xe2, 0xa0, 0x66, 0x58, 0xf7, 0x46, 0xf8, 0xc7, 0x0b, 0xb5, 0x1e, 0xa7, 0xba, 0x36, 0xce, 0xdd, 0x36, 0x41, 0x98, 0x6e, 0x10, 0xf9, 0x3b, 0x70, 0xbb, 0xa1, 0xda, 0x00, 0x40, 0xd5, 0xa5, 0x3f, 0x87, 0x64, 0x32, 0x7c, 0xbc, 0x50, 0x52, 0x0e, 0x4f, 0x21, 0xbd} + + n := new(big.Int) + d := new(big.Int) + n.SetString(testEncryptOAEPData[0].modulus, 16) + d.SetString(testEncryptOAEPData[0].d, 16) + priv := new(PrivateKey) + priv.PublicKey = PublicKey{N: n, E: testEncryptOAEPData[0].e} + priv.D = d + sha1 := crypto.SHA1 + sha256 := crypto.SHA256 + + out, err := priv.Decrypt(random, in, &OAEPOptions{MGFHash: sha1, Hash: sha256}) + + if err != nil { + t.Errorf("error: %s", err) + } else if !bytes.Equal(out, msg) { + t.Errorf("bad result %#v (want %#v)", out, msg) + } +} + func TestEncryptDecryptOAEP(t *testing.T) { sha256 := sha256.New() n := new(big.Int)