diff --git a/src/crypto/tls/cipher_suites.go b/src/crypto/tls/cipher_suites.go index 80e4023a7f..ea16ef95bf 100644 --- a/src/crypto/tls/cipher_suites.go +++ b/src/crypto/tls/cipher_suites.go @@ -14,10 +14,100 @@ import ( "crypto/sha1" "crypto/sha256" "crypto/x509" - "golang.org/x/crypto/chacha20poly1305" + "fmt" "hash" + + "golang.org/x/crypto/chacha20poly1305" ) +// CipherSuite is a TLS cipher suite. Note that most functions in this package +// accept and expose cipher suite IDs instead of this type. +type CipherSuite struct { + ID uint16 + Name string + + // Supported versions is the list of TLS protocol versions that can + // negotiate this cipher suite. + SupportedVersions []uint16 + + // Insecure is true if the cipher suite has known security issues + // due to its primitives, design, or implementation. + Insecure bool +} + +var ( + supportedUpToTLS12 = []uint16{VersionTLS10, VersionTLS11, VersionTLS12} + supportedOnlyTLS12 = []uint16{VersionTLS12} + supportedOnlyTLS13 = []uint16{VersionTLS13} +) + +// CipherSuites returns a list of cipher suites currently implemented by this +// package, excluding those with security issues, which are returned by +// InsecureCipherSuites. +// +// The list is sorted by ID. Note that the default cipher suites selected by +// this package might depend on logic that can't be captured by a static list. +func CipherSuites() []*CipherSuite { + return []*CipherSuite{ + {TLS_RSA_WITH_3DES_EDE_CBC_SHA, "TLS_RSA_WITH_3DES_EDE_CBC_SHA", supportedUpToTLS12, false}, + {TLS_RSA_WITH_AES_128_CBC_SHA, "TLS_RSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false}, + {TLS_RSA_WITH_AES_256_CBC_SHA, "TLS_RSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false}, + {TLS_RSA_WITH_AES_128_GCM_SHA256, "TLS_RSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false}, + {TLS_RSA_WITH_AES_256_GCM_SHA384, "TLS_RSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false}, + + {TLS_AES_128_GCM_SHA256, "TLS_AES_128_GCM_SHA256", supportedOnlyTLS13, false}, + {TLS_AES_256_GCM_SHA384, "TLS_AES_256_GCM_SHA384", supportedOnlyTLS13, false}, + {TLS_CHACHA20_POLY1305_SHA256, "TLS_CHACHA20_POLY1305_SHA256", supportedOnlyTLS13, false}, + + {TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false}, + {TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA, "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false}, + {TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA, "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA", supportedUpToTLS12, false}, + {TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA", supportedUpToTLS12, false}, + {TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA, "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA", supportedUpToTLS12, false}, + {TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256, "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false}, + {TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384, "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false}, + {TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256", supportedOnlyTLS12, false}, + {TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384", supportedOnlyTLS12, false}, + {TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256, "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256", supportedOnlyTLS12, false}, + {TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256, "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256", supportedOnlyTLS12, false}, + } +} + +// InsecureCipherSuites returns a list of cipher suites currently implemented by +// this package and which have security issues. +// +// Most applications should not use the cipher suites in this list, and should +// only use those returned by CipherSuites. +func InsecureCipherSuites() []*CipherSuite { + // RC4 suites are broken because RC4 is. + // CBC-SHA256 suites have no Lucky13 countermeasures. + return []*CipherSuite{ + {TLS_RSA_WITH_RC4_128_SHA, "TLS_RSA_WITH_RC4_128_SHA", supportedUpToTLS12, true}, + {TLS_RSA_WITH_AES_128_CBC_SHA256, "TLS_RSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true}, + {TLS_ECDHE_ECDSA_WITH_RC4_128_SHA, "TLS_ECDHE_ECDSA_WITH_RC4_128_SHA", supportedUpToTLS12, true}, + {TLS_ECDHE_RSA_WITH_RC4_128_SHA, "TLS_ECDHE_RSA_WITH_RC4_128_SHA", supportedUpToTLS12, true}, + {TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true}, + {TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256", supportedOnlyTLS12, true}, + } +} + +// CipherSuiteName returns the standard name for the passed cipher suite ID +// (e.g. "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256"), or a fallback representation +// of the ID value if the cipher suite is not implemented by this package. +func CipherSuiteName(id uint16) string { + for _, c := range CipherSuites() { + if c.ID == id { + return c.Name + } + } + for _, c := range InsecureCipherSuites() { + if c.ID == id { + return c.Name + } + } + return fmt.Sprintf("0x%04X", id) +} + // a keyAgreement implements the client and server side of a TLS key agreement // protocol by generating and processing key exchange messages. type keyAgreement interface { diff --git a/src/crypto/tls/tls_test.go b/src/crypto/tls/tls_test.go index 084101a51f..178b519f1c 100644 --- a/src/crypto/tls/tls_test.go +++ b/src/crypto/tls/tls_test.go @@ -1215,6 +1215,90 @@ func TestClientHelloInfo_SupportsCertificate(t *testing.T) { } } +func TestCipherSuites(t *testing.T) { + var lastID uint16 + for _, c := range CipherSuites() { + if lastID > c.ID { + t.Errorf("CipherSuites are not ordered by ID: got %#04x after %#04x", c.ID, lastID) + } else { + lastID = c.ID + } + + if c.Insecure { + t.Errorf("%#04x: Insecure CipherSuite returned by CipherSuites()", c.ID) + } + } + lastID = 0 + for _, c := range InsecureCipherSuites() { + if lastID > c.ID { + t.Errorf("InsecureCipherSuites are not ordered by ID: got %#04x after %#04x", c.ID, lastID) + } else { + lastID = c.ID + } + + if !c.Insecure { + t.Errorf("%#04x: not Insecure CipherSuite returned by InsecureCipherSuites()", c.ID) + } + } + + cipherSuiteByID := func(id uint16) *CipherSuite { + for _, c := range CipherSuites() { + if c.ID == id { + return c + } + } + for _, c := range InsecureCipherSuites() { + if c.ID == id { + return c + } + } + return nil + } + + for _, c := range cipherSuites { + cc := cipherSuiteByID(c.id) + if cc == nil { + t.Errorf("%#04x: no CipherSuite entry", c.id) + continue + } + + if defaultOff := c.flags&suiteDefaultOff != 0; defaultOff != cc.Insecure { + t.Errorf("%#04x: Insecure %v, expected %v", c.id, cc.Insecure, defaultOff) + } + if tls12Only := c.flags&suiteTLS12 != 0; tls12Only && len(cc.SupportedVersions) != 1 { + t.Errorf("%#04x: suite is TLS 1.2 only, but SupportedVersions is %v", c.id, cc.SupportedVersions) + } else if !tls12Only && len(cc.SupportedVersions) != 3 { + t.Errorf("%#04x: suite TLS 1.0-1.2, but SupportedVersions is %v", c.id, cc.SupportedVersions) + } + + if got := CipherSuiteName(c.id); got != cc.Name { + t.Errorf("%#04x: unexpected CipherSuiteName: got %q, expected %q", c.id, got, cc.Name) + } + } + for _, c := range cipherSuitesTLS13 { + cc := cipherSuiteByID(c.id) + if cc == nil { + t.Errorf("%#04x: no CipherSuite entry", c.id) + continue + } + + if cc.Insecure { + t.Errorf("%#04x: Insecure %v, expected false", c.id, cc.Insecure) + } + if len(cc.SupportedVersions) != 1 || cc.SupportedVersions[0] != VersionTLS13 { + t.Errorf("%#04x: suite is TLS 1.3 only, but SupportedVersions is %v", c.id, cc.SupportedVersions) + } + + if got := CipherSuiteName(c.id); got != cc.Name { + t.Errorf("%#04x: unexpected CipherSuiteName: got %q, expected %q", c.id, got, cc.Name) + } + } + + if got := CipherSuiteName(0xabc); got != "0x0ABC" { + t.Errorf("unexpected fallback CipherSuiteName: got %q, expected 0x0ABC", got) + } +} + type brokenSigner struct{ crypto.Signer } func (s brokenSigner) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) (signature []byte, err error) {