AdGuardHome/util/tls.go
Simon Zolin 06b3378fd7 Merge: + DNS, Web: use only secure TLSv1.2 ciphers
Close #1384

Squashed commit of the following:

commit cd90abcce573a8e930446ba153565e553e6b81d5
Author: Simon Zolin <s.zolin@adguard.com>
Date:   Fri Mar 20 19:17:53 2020 +0300

    minor

commit a1914c5f41425e82cdedc9716bce84470afab65b
Merge: 72c53673 c8285c41
Author: Simon Zolin <s.zolin@adguard.com>
Date:   Fri Mar 20 19:17:21 2020 +0300

    Merge remote-tracking branch 'origin/master' into 1384-tls12-ciphers

commit 72c536737e0502bb397562ade47aedb9f2ae4494
Author: Simon Zolin <s.zolin@adguard.com>
Date:   Wed Mar 4 18:16:24 2020 +0300

    + DNS, Web: use only secure TLSv1.2 ciphers
2020-03-23 10:23:34 +03:00

97 lines
2.8 KiB
Go

package util
import (
"crypto/tls"
"crypto/x509"
"io/ioutil"
"os"
"runtime"
"github.com/AdguardTeam/golibs/log"
"golang.org/x/sys/cpu"
)
// LoadSystemRootCAs - load root CAs from the system
// Return the x509 certificate pool object
// Return nil if nothing has been found.
// This means that Go.crypto will use its default algorithm to find system root CA list.
// https://github.com/AdguardTeam/AdGuardHome/issues/1311
func LoadSystemRootCAs() *x509.CertPool {
if runtime.GOOS != "linux" {
return nil
}
// Directories with the system root certificates, that aren't supported by Go.crypto
dirs := []string{
"/opt/etc/ssl/certs", // Entware
}
roots := x509.NewCertPool()
for _, dir := range dirs {
fis, err := ioutil.ReadDir(dir)
if err != nil {
if !os.IsNotExist(err) {
log.Error("Opening directory: %s: %s", dir, err)
}
continue
}
rootsAdded := false
for _, fi := range fis {
data, err := ioutil.ReadFile(dir + "/" + fi.Name())
if err == nil && roots.AppendCertsFromPEM(data) {
rootsAdded = true
}
}
if rootsAdded {
return roots
}
}
return nil
}
// InitTLSCiphers - the same as initDefaultCipherSuites() from src/crypto/tls/common.go
// but with the difference that we don't use so many other default ciphers.
func InitTLSCiphers() []uint16 {
var ciphers []uint16
// Check the cpu flags for each platform that has optimized GCM implementations.
// Worst case, these variables will just all be false.
var (
hasGCMAsmAMD64 = cpu.X86.HasAES && cpu.X86.HasPCLMULQDQ
hasGCMAsmARM64 = cpu.ARM64.HasAES && cpu.ARM64.HasPMULL
// Keep in sync with crypto/aes/cipher_s390x.go.
hasGCMAsmS390X = cpu.S390X.HasAES && cpu.S390X.HasAESCBC && cpu.S390X.HasAESCTR && (cpu.S390X.HasGHASH || cpu.S390X.HasAESGCM)
hasGCMAsm = hasGCMAsmAMD64 || hasGCMAsmARM64 || hasGCMAsmS390X
)
if hasGCMAsm {
// If AES-GCM hardware is provided then prioritise AES-GCM
// cipher suites.
ciphers = []uint16{
tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
}
} else {
// Without AES-GCM hardware, we put the ChaCha20-Poly1305
// cipher suites first.
ciphers = []uint16{
tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
}
}
otherCiphers := []uint16{
tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
}
ciphers = append(ciphers, otherCiphers...)
return ciphers
}