crypto/tls: set default minimum client version to TLS 1.2

Updates #45428

Change-Id: I5d70066d4091196ec6f8bfc2edf3d78fdc0520c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/359779
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>
This commit is contained in:
Filippo Valsorda 2021-10-31 23:13:18 -04:00
parent a316702d43
commit b0a9ca52e9
6 changed files with 59 additions and 17 deletions

View file

@ -156,7 +156,7 @@ func (c *Conn) readClientHello(ctx context.Context) (*clientHelloMsg, error) {
if len(clientHello.supportedVersions) == 0 {
clientVersions = supportedVersionsFromMax(clientHello.vers)
}
c.vers, ok = c.config.mutualVersion(clientVersions)
c.vers, ok = c.config.mutualVersion(roleServer, clientVersions)
if !ok {
c.sendAlert(alertProtocolVersion)
return nil, fmt.Errorf("tls: client offered only unsupported versions: %x", clientVersions)
@ -191,7 +191,7 @@ func (hs *serverHandshakeState) processClientHello() error {
hs.hello.random = make([]byte, 32)
serverRandom := hs.hello.random
// Downgrade protection canaries. See RFC 8446, Section 4.1.3.
maxVers := c.config.maxSupportedVersion()
maxVers := c.config.maxSupportedVersion(roleServer)
if maxVers >= VersionTLS12 && c.vers < maxVers || testingOnlyForceDowngradeCanary {
if c.vers == VersionTLS12 {
copy(serverRandom[24:], downgradeCanaryTLS12)
@ -354,7 +354,7 @@ func (hs *serverHandshakeState) pickCipherSuite() error {
for _, id := range hs.clientHello.cipherSuites {
if id == TLS_FALLBACK_SCSV {
// The client is doing a fallback connection. See RFC 7507.
if hs.clientHello.vers < c.config.maxSupportedVersion() {
if hs.clientHello.vers < c.config.maxSupportedVersion(roleServer) {
c.sendAlert(alertInappropriateFallback)
return errors.New("tls: client using inappropriate protocol fallback")
}