types: add types/tls.go for strongly-typed TLS versions and cipher suites (#11645)

types: add TLS constants

types: distinguish between human and Envoy serialization for TLSVersion constants

types: add DeprecatedAgentTLSVersions for backwards compatibility

types: add methods for printing TLSVersion as strings

types: add TLSVersionInvalid error value

types: add a basic test for TLSVersion comparison

types: add TLS cihper suite mapping using IANA constant names and values

types: adding ConsulAutoConfigTLSVersionStrings

changelog: add entry for TLSVersion and TLSCipherSuite types

types: initialize TLSVerison constants starting at zero

types: remove TLSVersionInvalid < 0 test

types: update note for ConsulAutoConfigTLSVersionStrings

types: programmatically invert TLSCipherSuites for HumanTLSCipherSuiteStrings lookup map

Co-authored-by: Dan Upton <daniel@floppy.co>

types: add test for TLSVersion zero-value

types: remove unused EnvoyTLSVersionStrings

types: implement MarshalJSON for TLSVersion

types: implement TLSVersionUnspecified as zero value

types: delegate TLS.MarshalJSON to json.Marshal, use ConsulConfigTLSVersionStrings as default String() values

Co-authored-by: Dan Upton <daniel@floppy.co>
This commit is contained in:
Mike Morris 2021-12-03 20:17:55 -05:00 committed by GitHub
parent 42a528f163
commit 78a008daf6
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3 changed files with 237 additions and 0 deletions

3
.changelog/11645.txt Normal file
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```release-note:improvement
types: add TLSVersion and TLSCipherSuite
```

185
types/tls.go Normal file
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package types
import (
"encoding/json"
"fmt"
)
// TLSVersion is a strongly-typed int used for relative comparison
// (minimum, maximum, greater than, less than) of TLS versions
type TLSVersion int
const (
// Error value, excluded from lookup maps
TLSVersionInvalid TLSVersion = iota - 1
// Explicit unspecified zero-value to avoid overwriting parent defaults
TLSVersionUnspecified
// Explictly allow implementation to select TLS version
// May be useful to supercede defaults specified at a higher layer
TLSVersionAuto
_ // Placeholder for SSLv3, hopefully we won't have to add this
// TLS versions
TLSv1_0
TLSv1_1
TLSv1_2
TLSv1_3
)
var (
TLSVersions = map[string]TLSVersion{
"TLS_AUTO": TLSVersionAuto,
"TLSv1_0": TLSv1_0,
"TLSv1_1": TLSv1_1,
"TLSv1_2": TLSv1_2,
"TLSv1_3": TLSv1_3,
}
// NOTE: This interface is deprecated in favor of TLSVersions
// and should be eventually removed in a future release.
DeprecatedConsulAgentTLSVersions = map[string]TLSVersion{
"": TLSVersionAuto,
"tls10": TLSv1_0,
"tls11": TLSv1_1,
"tls12": TLSv1_2,
"tls13": TLSv1_3,
}
HumanTLSVersionStrings = map[TLSVersion]string{
TLSVersionAuto: "Allow implementation to select TLS version",
TLSv1_0: "TLS 1.0",
TLSv1_1: "TLS 1.1",
TLSv1_2: "TLS 1.2",
TLSv1_3: "TLS 1.3",
}
ConsulConfigTLSVersionStrings = func() map[TLSVersion]string {
inverted := make(map[TLSVersion]string, len(TLSVersions))
for k, v := range TLSVersions {
inverted[v] = k
}
return inverted
}()
// NOTE: these currently map to the deprecated config strings to support the
// deployment pattern of upgrading servers first. This map should eventually
// be removed and any lookups updated to use ConsulConfigTLSVersionStrings
// with newer config strings instead in a future release.
ConsulAutoConfigTLSVersionStrings = map[TLSVersion]string{
TLSVersionAuto: "",
TLSv1_0: "tls10",
TLSv1_1: "tls11",
TLSv1_2: "tls12",
TLSv1_3: "tls13",
}
)
func (v TLSVersion) String() string {
return ConsulConfigTLSVersionStrings[v]
}
func (v TLSVersion) MarshalJSON() ([]byte, error) {
return json.Marshal(v.String())
}
func (v *TLSVersion) UnmarshalJSON(bytes []byte) error {
versionStr := string(bytes)
if n := len(versionStr); n > 1 && versionStr[0] == '"' && versionStr[n-1] == '"' {
versionStr = versionStr[1 : n-1] // trim surrounding quotes
}
if version, ok := TLSVersions[versionStr]; ok {
*v = version
return nil
}
*v = TLSVersionInvalid
return fmt.Errorf("no matching TLS Version found for %s", versionStr)
}
// IANA cipher suite constants and values as defined at
// https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml
// This is the total list of TLS 1.2-style cipher suites
// which are currently supported by either Envoy 1.21 or the Consul agent
// via Go, and may change as some older suites are removed in future
// Envoy releases and Consul drops support for older Envoy versions,
// and as supported cipher suites in the Go runtime change.
//
// The naming convention for cipher suites changed in TLS 1.3
// but constant values should still be globally unqiue
// Handling validation on a subset of TLSCipherSuite constants
// would be a future exercise if cipher suites for TLS 1.3 ever
// become configurable in BoringSSL, Envoy, or other implementation
type TLSCipherSuite uint16
const (
// Envoy cipher suites also used by Consul agent
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 TLSCipherSuite = 0xc02b
TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 = 0xcca9 // Not used by Consul agent yet
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 = 0xc02f
TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 = 0xcca8 // Not used by Consul agent yet
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA = 0xc009
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA = 0xc013
TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 = 0xc02c
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 = 0xc030
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA = 0xc00a
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA = 0xc014
// Older cipher suites not supported for Consul agent TLS, will eventually be removed from Envoy defaults
TLS_RSA_WITH_AES_128_GCM_SHA256 = 0x009c
TLS_RSA_WITH_AES_128_CBC_SHA = 0x002f
TLS_RSA_WITH_AES_256_GCM_SHA384 = 0x009d
TLS_RSA_WITH_AES_256_CBC_SHA = 0x0035
// Additional cipher suites used by Consul agent but not Envoy
// TODO: these are both explicitly listed as insecure and disabled in the Go source, should they be removed?
// https://cs.opensource.google/go/go/+/refs/tags/go1.17.3:src/crypto/tls/cipher_suites.go;l=329-330
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 = 0x0023
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 = 0xc027
)
var (
TLSCipherSuites = map[string]TLSCipherSuite{
"TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256": TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,
"TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA": TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
"TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256": TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
"TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA": TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
"TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384": TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
"TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256": TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
"TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA": TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
"TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256": TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
"TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA": TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
"TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384": TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
"TLS_RSA_WITH_AES_128_GCM_SHA256": TLS_RSA_WITH_AES_128_GCM_SHA256,
"TLS_RSA_WITH_AES_128_CBC_SHA": TLS_RSA_WITH_AES_128_CBC_SHA,
"TLS_RSA_WITH_AES_256_GCM_SHA384": TLS_RSA_WITH_AES_256_GCM_SHA384,
"TLS_RSA_WITH_AES_256_CBC_SHA": TLS_RSA_WITH_AES_256_CBC_SHA,
"TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256": TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
"TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256": TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
}
HumanTLSCipherSuiteStrings = func() map[TLSCipherSuite]string {
inverted := make(map[TLSCipherSuite]string, len(TLSCipherSuites))
for k, v := range TLSCipherSuites {
inverted[v] = k
}
return inverted
}()
EnvoyTLSCipherSuiteStrings = map[TLSCipherSuite]string{
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256: "ECDHE-ECDSA-AES128-GCM-SHA256",
TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256: "ECDHE-ECDSA-CHACHA20-POLY1305",
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256: "ECDHE-RSA-AES128-GCM-SHA256",
TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256: "ECDHE-RSA-CHACHA20-POLY1305",
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA: "ECDHE-ECDSA-AES128-SHA",
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA: "ECDHE-RSA-AES128-SHA",
TLS_RSA_WITH_AES_128_GCM_SHA256: "AES128-GCM-SHA256",
TLS_RSA_WITH_AES_128_CBC_SHA: "AES128-SHA",
TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384: "ECDHE-ECDSA-AES256-GCM-SHA384",
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384: "ECDHE-RSA-AES256-GCM-SHA384",
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA: "ECDHE-ECDSA-AES256-SHA",
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA: "ECDHE-RSA-AES256-SHA",
TLS_RSA_WITH_AES_256_GCM_SHA384: "AES256-GCM-SHA384",
TLS_RSA_WITH_AES_256_CBC_SHA: "AES256-SHA",
}
)

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types/tls_test.go Normal file
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package types
import (
"encoding/json"
"testing"
"github.com/stretchr/testify/require"
)
func TestTLSVersion_PartialEq(t *testing.T) {
require.Greater(t, TLSv1_3, TLSv1_2)
require.Greater(t, TLSv1_2, TLSv1_1)
require.Greater(t, TLSv1_1, TLSv1_0)
require.Less(t, TLSv1_2, TLSv1_3)
require.Less(t, TLSv1_1, TLSv1_2)
require.Less(t, TLSv1_0, TLSv1_1)
}
func TestTLSVersion_Invalid(t *testing.T) {
var zeroValue TLSVersion
require.NotEqual(t, TLSVersionInvalid, zeroValue)
require.NotEqual(t, TLSVersionInvalid, TLSVersionUnspecified)
require.NotEqual(t, TLSVersionInvalid, TLSVersionAuto)
}
func TestTLSVersion_Zero(t *testing.T) {
var zeroValue TLSVersion
require.Equal(t, TLSVersionUnspecified, zeroValue)
require.NotEqual(t, TLSVersionUnspecified, TLSVersionInvalid)
require.NotEqual(t, TLSVersionUnspecified, TLSVersionAuto)
}
func TestTLSVersion_ToJSON(t *testing.T) {
var tlsVersion TLSVersion
err := tlsVersion.UnmarshalJSON([]byte(`"foo"`))
require.Error(t, err)
require.Equal(t, tlsVersion, TLSVersionInvalid)
for str, version := range TLSVersions {
versionJSON, err := json.Marshal(version)
require.NoError(t, err)
require.Equal(t, versionJSON, []byte(`"`+str+`"`))
err = tlsVersion.UnmarshalJSON([]byte(`"` + str + `"`))
require.NoError(t, err)
require.Equal(t, tlsVersion, version)
}
}