// Copyright (c) 2015-2021 MinIO, Inc.//// This file is part of MinIO Object Storage stack//// This program is free software: you can redistribute it and/or modify// it under the terms of the GNU Affero General Public License as published by// the Free Software Foundation, either version 3 of the License, or// (at your option) any later version.//// This program is distributed in the hope that it will be useful// but WITHOUT ANY WARRANTY; without even the implied warranty of// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the// GNU Affero General Public License for more details.//// You should have received a copy of the GNU Affero General Public License// along with this program.  If not, see <http://www.gnu.org/licenses/>. // Package fips provides functionality to configure cryptographic// implementations compliant with FIPS 140.//// FIPS 140 [1] is a US standard for data processing that specifies// requirements for cryptographic modules. Software that is "FIPS 140// compliant" must use approved cryptographic primitives only and that// are implemented by a FIPS 140 certified cryptographic module.//// So, FIPS 140 requires that a certified implementation of e.g. AES// is used to implement more high-level cryptographic protocols.// It does not require any specific security criteria for those// high-level protocols. FIPS 140 focuses only on the implementation// and usage of the most low-level cryptographic building blocks.//// [1]: https://en.wikipedia.org/wiki/FIPS_140package fips import (	"crypto/tls" 	"github.com/minio/sio") // Enabled indicates whether cryptographic primitives,// like AES or SHA-256, are implemented using a FIPS 140// certified module.//// If FIPS-140 is enabled no non-NIST/FIPS approved// primitives must be used.const Enabled = enabled // DARECiphers returns a list of supported cipher suites// for the DARE object encryption.func DARECiphers() []byte {	if Enabled {		return []byte{sio.AES_256_GCM}	}	return []byte{sio.AES_256_GCM, sio.CHACHA20_POLY1305}} // TLSCiphers returns a list of supported TLS transport// cipher suite IDs.//// The list contains only ciphers that use AES-GCM or// (non-FIPS) CHACHA20-POLY1305 and ellitpic curve key// exchange.func TLSCiphers() []uint16 {	if Enabled {		return []uint16{			tls.TLS_AES_128_GCM_SHA256, // TLS 1.3			tls.TLS_AES_256_GCM_SHA384,			tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, // TLS 1.2			tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,			tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,			tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,		}	}	return []uint16{		tls.TLS_CHACHA20_POLY1305_SHA256, // TLS 1.3		tls.TLS_AES_128_GCM_SHA256,		tls.TLS_AES_256_GCM_SHA384,		tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305, // TLS 1.2		tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,		tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,		tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,		tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,		tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,	}} // TLSCiphersBackwardCompatible returns a list of supported// TLS transport cipher suite IDs.//// In contrast to TLSCiphers, the list contains additional// ciphers for backward compatibility. In particular, AES-CBC// and non-ECDHE ciphers.func TLSCiphersBackwardCompatible() []uint16 {	if Enabled {		return []uint16{			tls.TLS_AES_128_GCM_SHA256, // TLS 1.3			tls.TLS_AES_256_GCM_SHA384,			tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, // TLS 1.2 ECDHE GCM			tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,			tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,			tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,			tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, // TLS 1.2 ECDHE CBC			tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,			tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,			tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,			tls.TLS_RSA_WITH_AES_128_GCM_SHA256, // TLS 1.2 non-ECDHE			tls.TLS_RSA_WITH_AES_256_GCM_SHA384,			tls.TLS_RSA_WITH_AES_128_CBC_SHA,			tls.TLS_RSA_WITH_AES_256_CBC_SHA,		}	}	return []uint16{		tls.TLS_CHACHA20_POLY1305_SHA256, // TLS 1.3		tls.TLS_AES_128_GCM_SHA256,		tls.TLS_AES_256_GCM_SHA384,		tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256, // TLS 1.2 ECDHE GCM / POLY1305		tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,		tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,		tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,		tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,		tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,		tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, // TLS 1.2 ECDHE CBC		tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,		tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,		tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,		tls.TLS_RSA_WITH_AES_128_GCM_SHA256, // TLS 1.2 non-ECDHE		tls.TLS_RSA_WITH_AES_256_GCM_SHA384,		tls.TLS_RSA_WITH_AES_128_CBC_SHA,		tls.TLS_RSA_WITH_AES_256_CBC_SHA,	}} // TLSCurveIDs returns a list of supported elliptic curve IDs// in preference order.func TLSCurveIDs() []tls.CurveID {	var curves []tls.CurveID	if !Enabled {		curves = append(curves, tls.X25519) // Only enable X25519 in non-FIPS mode	}	curves = append(curves, tls.CurveP256)	if go18 {		// With go1.18 enable P384, P521 newer constant time implementations.		curves = append(curves, tls.CurveP384, tls.CurveP521)	}	return curves}