// Copyright 2013 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 rsa_test import ( "bufio" "bytes" "compress/bzip2" "crypto" "crypto/rand" . "crypto/rsa" "crypto/sha1" "crypto/sha256" "encoding/hex" "math/big" "os" "strconv" "strings" "testing" ) func TestEMSAPSS(t *testing.T) { // Test vector in file pss-int.txt from: ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1-vec.zip msg := []byte{ 0x85, 0x9e, 0xef, 0x2f, 0xd7, 0x8a, 0xca, 0x00, 0x30, 0x8b, 0xdc, 0x47, 0x11, 0x93, 0xbf, 0x55, 0xbf, 0x9d, 0x78, 0xdb, 0x8f, 0x8a, 0x67, 0x2b, 0x48, 0x46, 0x34, 0xf3, 0xc9, 0xc2, 0x6e, 0x64, 0x78, 0xae, 0x10, 0x26, 0x0f, 0xe0, 0xdd, 0x8c, 0x08, 0x2e, 0x53, 0xa5, 0x29, 0x3a, 0xf2, 0x17, 0x3c, 0xd5, 0x0c, 0x6d, 0x5d, 0x35, 0x4f, 0xeb, 0xf7, 0x8b, 0x26, 0x02, 0x1c, 0x25, 0xc0, 0x27, 0x12, 0xe7, 0x8c, 0xd4, 0x69, 0x4c, 0x9f, 0x46, 0x97, 0x77, 0xe4, 0x51, 0xe7, 0xf8, 0xe9, 0xe0, 0x4c, 0xd3, 0x73, 0x9c, 0x6b, 0xbf, 0xed, 0xae, 0x48, 0x7f, 0xb5, 0x56, 0x44, 0xe9, 0xca, 0x74, 0xff, 0x77, 0xa5, 0x3c, 0xb7, 0x29, 0x80, 0x2f, 0x6e, 0xd4, 0xa5, 0xff, 0xa8, 0xba, 0x15, 0x98, 0x90, 0xfc, } salt := []byte{ 0xe3, 0xb5, 0xd5, 0xd0, 0x02, 0xc1, 0xbc, 0xe5, 0x0c, 0x2b, 0x65, 0xef, 0x88, 0xa1, 0x88, 0xd8, 0x3b, 0xce, 0x7e, 0x61, } expected := []byte{ 0x66, 0xe4, 0x67, 0x2e, 0x83, 0x6a, 0xd1, 0x21, 0xba, 0x24, 0x4b, 0xed, 0x65, 0x76, 0xb8, 0x67, 0xd9, 0xa4, 0x47, 0xc2, 0x8a, 0x6e, 0x66, 0xa5, 0xb8, 0x7d, 0xee, 0x7f, 0xbc, 0x7e, 0x65, 0xaf, 0x50, 0x57, 0xf8, 0x6f, 0xae, 0x89, 0x84, 0xd9, 0xba, 0x7f, 0x96, 0x9a, 0xd6, 0xfe, 0x02, 0xa4, 0xd7, 0x5f, 0x74, 0x45, 0xfe, 0xfd, 0xd8, 0x5b, 0x6d, 0x3a, 0x47, 0x7c, 0x28, 0xd2, 0x4b, 0xa1, 0xe3, 0x75, 0x6f, 0x79, 0x2d, 0xd1, 0xdc, 0xe8, 0xca, 0x94, 0x44, 0x0e, 0xcb, 0x52, 0x79, 0xec, 0xd3, 0x18, 0x3a, 0x31, 0x1f, 0xc8, 0x96, 0xda, 0x1c, 0xb3, 0x93, 0x11, 0xaf, 0x37, 0xea, 0x4a, 0x75, 0xe2, 0x4b, 0xdb, 0xfd, 0x5c, 0x1d, 0xa0, 0xde, 0x7c, 0xec, 0xdf, 0x1a, 0x89, 0x6f, 0x9d, 0x8b, 0xc8, 0x16, 0xd9, 0x7c, 0xd7, 0xa2, 0xc4, 0x3b, 0xad, 0x54, 0x6f, 0xbe, 0x8c, 0xfe, 0xbc, } hash := sha1.New() hash.Write(msg) hashed := hash.Sum(nil) encoded, err := EMSAPSSEncode(hashed, 1023, salt, sha1.New()) if err != nil { t.Errorf("Error from emsaPSSEncode: %s\n", err) } if !bytes.Equal(encoded, expected) { t.Errorf("Bad encoding. got %x, want %x", encoded, expected) } if err = EMSAPSSVerify(hashed, encoded, 1023, len(salt), sha1.New()); err != nil { t.Errorf("Bad verification: %s", err) } } // TestPSSGolden tests all the test vectors in pss-vect.txt from // ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1-vec.zip func TestPSSGolden(t *testing.T) { inFile, err := os.Open("testdata/pss-vect.txt.bz2") if err != nil { t.Fatalf("Failed to open input file: %s", err) } defer inFile.Close() // The pss-vect.txt file contains RSA keys and then a series of // signatures. A goroutine is used to preprocess the input by merging // lines, removing spaces in hex values and identifying the start of // new keys and signature blocks. const newKeyMarker = "START NEW KEY" const newSignatureMarker = "START NEW SIGNATURE" values := make(chan string) go func() { defer close(values) scanner := bufio.NewScanner(bzip2.NewReader(inFile)) var partialValue string lastWasValue := true for scanner.Scan() { line := scanner.Text() switch { case len(line) == 0: if len(partialValue) > 0 { values <- strings.ReplaceAll(partialValue, " ", "") partialValue = "" lastWasValue = true } continue case strings.HasPrefix(line, "# ======") && lastWasValue: values <- newKeyMarker lastWasValue = false case strings.HasPrefix(line, "# ------") && lastWasValue: values <- newSignatureMarker lastWasValue = false case strings.HasPrefix(line, "#"): continue default: partialValue += line } } if err := scanner.Err(); err != nil { panic(err) } }() var key *PublicKey var hashed []byte hash := crypto.SHA1 h := hash.New() opts := &PSSOptions{ SaltLength: PSSSaltLengthEqualsHash, } for marker := range values { switch marker { case newKeyMarker: key = new(PublicKey) nHex, ok := <-values if !ok { continue } key.N = bigFromHex(nHex) key.E = intFromHex(<-values) // We don't care for d, p, q, dP, dQ or qInv. for i := 0; i < 6; i++ { <-values } case newSignatureMarker: msg := fromHex(<-values) <-values // skip salt sig := fromHex(<-values) h.Reset() h.Write(msg) hashed = h.Sum(hashed[:0]) if err := VerifyPSS(key, hash, hashed, sig, opts); err != nil { t.Error(err) } default: t.Fatalf("unknown marker: " + marker) } } } // TestPSSOpenSSL ensures that we can verify a PSS signature from OpenSSL with // the default options. OpenSSL sets the salt length to be maximal. func TestPSSOpenSSL(t *testing.T) { hash := crypto.SHA256 h := hash.New() h.Write([]byte("testing")) hashed := h.Sum(nil) // Generated with `echo -n testing | openssl dgst -sign key.pem -sigopt rsa_padding_mode:pss -sha256 > sig` sig := []byte{ 0x95, 0x59, 0x6f, 0xd3, 0x10, 0xa2, 0xe7, 0xa2, 0x92, 0x9d, 0x4a, 0x07, 0x2e, 0x2b, 0x27, 0xcc, 0x06, 0xc2, 0x87, 0x2c, 0x52, 0xf0, 0x4a, 0xcc, 0x05, 0x94, 0xf2, 0xc3, 0x2e, 0x20, 0xd7, 0x3e, 0x66, 0x62, 0xb5, 0x95, 0x2b, 0xa3, 0x93, 0x9a, 0x66, 0x64, 0x25, 0xe0, 0x74, 0x66, 0x8c, 0x3e, 0x92, 0xeb, 0xc6, 0xe6, 0xc0, 0x44, 0xf3, 0xb4, 0xb4, 0x2e, 0x8c, 0x66, 0x0a, 0x37, 0x9c, 0x69, } if err := VerifyPSS(&rsaPrivateKey.PublicKey, hash, hashed, sig, nil); err != nil { t.Error(err) } } func TestPSSNilOpts(t *testing.T) { hash := crypto.SHA256 h := hash.New() h.Write([]byte("testing")) hashed := h.Sum(nil) SignPSS(rand.Reader, rsaPrivateKey, hash, hashed, nil) } func TestPSSSigning(t *testing.T) { var saltLengthCombinations = []struct { signSaltLength, verifySaltLength int good bool }{ {PSSSaltLengthAuto, PSSSaltLengthAuto, true}, {PSSSaltLengthEqualsHash, PSSSaltLengthAuto, true}, {PSSSaltLengthEqualsHash, PSSSaltLengthEqualsHash, true}, {PSSSaltLengthEqualsHash, 8, false}, {PSSSaltLengthAuto, PSSSaltLengthEqualsHash, false}, {8, 8, true}, {PSSSaltLengthAuto, 42, true}, {PSSSaltLengthAuto, 20, false}, {PSSSaltLengthAuto, -2, false}, } hash := crypto.SHA1 h := hash.New() h.Write([]byte("testing")) hashed := h.Sum(nil) var opts PSSOptions for i, test := range saltLengthCombinations { opts.SaltLength = test.signSaltLength sig, err := SignPSS(rand.Reader, rsaPrivateKey, hash, hashed, &opts) if err != nil { t.Errorf("#%d: error while signing: %s", i, err) continue } opts.SaltLength = test.verifySaltLength err = VerifyPSS(&rsaPrivateKey.PublicKey, hash, hashed, sig, &opts) if (err == nil) != test.good { t.Errorf("#%d: bad result, wanted: %t, got: %s", i, test.good, err) } } } func TestPSS513(t *testing.T) { // See Issue 42741, and separately, RFC 8017: "Note that the octet length of // EM will be one less than k if modBits - 1 is divisible by 8 and equal to // k otherwise, where k is the length in octets of the RSA modulus n." key, err := GenerateKey(rand.Reader, 513) if err != nil { t.Fatal(err) } digest := sha256.Sum256([]byte("message")) signature, err := key.Sign(rand.Reader, digest[:], &PSSOptions{ SaltLength: PSSSaltLengthAuto, Hash: crypto.SHA256, }) if err != nil { t.Fatal(err) } err = VerifyPSS(&key.PublicKey, crypto.SHA256, digest[:], signature, nil) if err != nil { t.Error(err) } } func bigFromHex(hex string) *big.Int { n, ok := new(big.Int).SetString(hex, 16) if !ok { panic("bad hex: " + hex) } return n } func intFromHex(hex string) int { i, err := strconv.ParseInt(hex, 16, 32) if err != nil { panic(err) } return int(i) } func fromHex(hexStr string) []byte { s, err := hex.DecodeString(hexStr) if err != nil { panic(err) } return s } func TestInvalidPSSSaltLength(t *testing.T) { key, err := GenerateKey(rand.Reader, 245) if err != nil { t.Fatal(err) } digest := sha256.Sum256([]byte("message")) // We don't check the exact error matches, because crypto/rsa and crypto/internal/boring // return two different error variables, which have the same content but are not equal. if _, err := SignPSS(rand.Reader, key, crypto.SHA256, digest[:], &PSSOptions{ SaltLength: -2, Hash: crypto.SHA256, }); err.Error() != InvalidSaltLenErr.Error() { t.Fatalf("SignPSS unexpected error: got %v, want %v", err, InvalidSaltLenErr) } // We don't check the specific error here, because crypto/rsa and crypto/internal/boring // return different errors, so we just check that _an error_ was returned. if err := VerifyPSS(&key.PublicKey, crypto.SHA256, []byte{1, 2, 3}, make([]byte, 31), &PSSOptions{ SaltLength: -2, }); err == nil { t.Fatal("VerifyPSS unexpected success") } }