rename crypto.Signer to crypto.CertChain

crypto/cert_chain.go

@@ -0,0 +1,82 @@
+package crypto
+
+import (
+	"crypto/tls"
+	"errors"
+	"strings"
+)
+
+// A CertChain holds a certificate and a private key
+type CertChain interface {
+	SignServerProof(sni string, chlo []byte, serverConfigData []byte) ([]byte, error)
+	GetCertsCompressed(sni string, commonSetHashes, cachedHashes []byte) ([]byte, error)
+	GetLeafCert(sni string) ([]byte, error)
+}
+
+// proofSource stores a key and a certificate for the server proof
+type certChain struct {
+	config *tls.Config
+}
+
+var _ CertChain = &certChain{}
+
+// NewCertChain loads the key and cert from files
+func NewCertChain(tlsConfig *tls.Config) (CertChain, error) {
+	return &certChain{config: tlsConfig}, nil
+}
+
+// SignServerProof signs CHLO and server config for use in the server proof
+func (c *certChain) SignServerProof(sni string, chlo []byte, serverConfigData []byte) ([]byte, error) {
+	cert, err := c.getCertForSNI(sni)
+	if err != nil {
+		return nil, err
+	}
+
+	return signServerProof(cert, chlo, serverConfigData)
+}
+
+// GetCertsCompressed gets the certificate in the format described by the QUIC crypto doc
+func (c *certChain) GetCertsCompressed(sni string, pCommonSetHashes, pCachedHashes []byte) ([]byte, error) {
+	cert, err := c.getCertForSNI(sni)
+	if err != nil {
+		return nil, err
+	}
+	return getCompressedCert(cert.Certificate, pCommonSetHashes, pCachedHashes)
+}
+
+// GetLeafCert gets the leaf certificate
+func (c *certChain) GetLeafCert(sni string) ([]byte, error) {
+	cert, err := c.getCertForSNI(sni)
+	if err != nil {
+		return nil, err
+	}
+	return cert.Certificate[0], nil
+}
+
+func (c *certChain) getCertForSNI(sni string) (*tls.Certificate, error) {
+	if c.config.GetCertificate != nil {
+		cert, err := c.config.GetCertificate(&tls.ClientHelloInfo{ServerName: sni})
+		if err != nil {
+			return nil, err
+		}
+		if cert != nil {
+			return cert, nil
+		}
+	}
+
+	if len(c.config.NameToCertificate) != 0 {
+		if cert, ok := c.config.NameToCertificate[sni]; ok {
+			return cert, nil
+		}
+		wildcardSNI := "*" + strings.TrimLeftFunc(sni, func(r rune) bool { return r != '.' })
+		if cert, ok := c.config.NameToCertificate[wildcardSNI]; ok {
+			return cert, nil
+		}
+	}
+
+	if len(c.config.Certificates) != 0 {
+		return &c.config.Certificates[0], nil
+	}
+
+	return nil, errors.New("no matching certificate found")
+}