utls/boring.go
Filippo Valsorda 035b9d2bbf crypto/tls: align FIPS-only mode with BoringSSL policy
This enables TLS 1.3, disables P-521, and disables non-ECDHE suites.

Fixes #64717
Updates #62372

Change-Id: I3a65b239ef0198bbdbe5e55e0810e7128f90a091
Reviewed-on: https://go-review.googlesource.com/c/go/+/549975
Reviewed-by: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2023-12-18 23:29:17 +00:00

102 lines
2.8 KiB
Go

// Copyright 2017 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.
//go:build boringcrypto
package tls
import "crypto/internal/boring/fipstls"
// The FIPS-only policies enforced here currently match BoringSSL's
// ssl_policy_fips_202205.
// needFIPS returns fipstls.Required(); it avoids a new import in common.go.
func needFIPS() bool {
return fipstls.Required()
}
// fipsMinVersion replaces c.minVersion in FIPS-only mode.
func fipsMinVersion(c *Config) uint16 {
// FIPS requires TLS 1.2 or TLS 1.3.
return VersionTLS12
}
// fipsMaxVersion replaces c.maxVersion in FIPS-only mode.
func fipsMaxVersion(c *Config) uint16 {
// FIPS requires TLS 1.2 or TLS 1.3.
return VersionTLS13
}
// default defaultFIPSCurvePreferences is the FIPS-allowed curves,
// in preference order (most preferable first).
var defaultFIPSCurvePreferences = []CurveID{CurveP256, CurveP384}
// fipsCurvePreferences replaces c.curvePreferences in FIPS-only mode.
func fipsCurvePreferences(c *Config) []CurveID {
if c == nil || len(c.CurvePreferences) == 0 {
return defaultFIPSCurvePreferences
}
var list []CurveID
for _, id := range c.CurvePreferences {
for _, allowed := range defaultFIPSCurvePreferences {
if id == allowed {
list = append(list, id)
break
}
}
}
return list
}
// defaultCipherSuitesFIPS are the FIPS-allowed cipher suites.
var defaultCipherSuitesFIPS = []uint16{
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
}
// fipsCipherSuites replaces c.cipherSuites in FIPS-only mode.
func fipsCipherSuites(c *Config) []uint16 {
if c == nil || c.CipherSuites == nil {
return defaultCipherSuitesFIPS
}
list := make([]uint16, 0, len(defaultCipherSuitesFIPS))
for _, id := range c.CipherSuites {
for _, allowed := range defaultCipherSuitesFIPS {
if id == allowed {
list = append(list, id)
break
}
}
}
return list
}
// defaultCipherSuitesTLS13FIPS are the FIPS-allowed cipher suites for TLS 1.3.
var defaultCipherSuitesTLS13FIPS = []uint16{
TLS_AES_128_GCM_SHA256,
TLS_AES_256_GCM_SHA384,
}
// fipsSupportedSignatureAlgorithms currently are a subset of
// defaultSupportedSignatureAlgorithms without Ed25519, SHA-1, and P-521.
var fipsSupportedSignatureAlgorithms = []SignatureScheme{
PSSWithSHA256,
PSSWithSHA384,
PSSWithSHA512,
PKCS1WithSHA256,
ECDSAWithP256AndSHA256,
PKCS1WithSHA384,
ECDSAWithP384AndSHA384,
PKCS1WithSHA512,
}
// supportedSignatureAlgorithms returns the supported signature algorithms.
func supportedSignatureAlgorithms() []SignatureScheme {
if !needFIPS() {
return defaultSupportedSignatureAlgorithms
}
return fipsSupportedSignatureAlgorithms
}