➖ update: remove unused boring files

// 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

}