feat: First steps towards using wildcard certificates

internal/certificates/certificate.go

@@ -38,7 +38,7 @@ func RenewCertificate(old *CertificateWrapper, acmeClient *lego.Client) (Certifi
 	}
 	wrapper := CertificateWrapper{
 		TlsCertificate:    &tlsCert,
-		Domain:            old.Domain,
+		DomainKey:         old.DomainKey,
 		NotAfter:          time.Now().Add(time.Hour * 24 * 60),
 		PrivateKeyEncoded: base64.StdEncoding.EncodeToString(new.PrivateKey),
 		Certificate:       new.Certificate,
@@ -47,7 +47,7 @@ func RenewCertificate(old *CertificateWrapper, acmeClient *lego.Client) (Certifi
 	return wrapper, nil
 }
 
-func ObtainNewCertificate(domains []string, acmeClient *lego.Client) (CertificateWrapper, error) {
+func ObtainNewCertificate(domains []string, domainKey string, acmeClient *lego.Client) (CertificateWrapper, error) {
 	req := certificate.ObtainRequest{
 		Domains: domains,
 		Bundle:  true,
@@ -64,7 +64,7 @@ func ObtainNewCertificate(domains []string, acmeClient *lego.Client) (Certificat
 
 	wrapper := CertificateWrapper{
 		TlsCertificate: &tlsCert,
-		Domain:         cert.Domain,
+		DomainKey:      domainKey,
 		//NotAfter:        tlsCert.Leaf.NotAfter,
 		NotAfter:          time.Now().Add(time.Hour * 24 * 60),
 		PrivateKeyEncoded: base64.StdEncoding.EncodeToString(cert.PrivateKey),
@@ -127,7 +127,7 @@ func MakeFallbackCertificate(pagesDomain string) (*CertificateWrapper, error) {
 	}
 	return &CertificateWrapper{
 		TlsCertificate:    &tlsCertificate,
-		Domain:            pagesDomain,
+		DomainKey:         "*." + pagesDomain,
 		NotAfter:          notAfter,
 		PrivateKeyEncoded: base64.StdEncoding.EncodeToString(certcrypto.PEMEncode(key)),
 		Certificate:       outBytes,

internal/certificates/store.go

@@ -14,11 +14,22 @@ import (
 
 // A convenience wrapper around a TLS certificate
 type CertificateWrapper struct {
+	// The parsed TLS certificate we can pass to the tls listener
 	TlsCertificate *tls.Certificate `json:"-"`
-	Domain            string           `json:"domain"`
+
+	// Key identifying for which domain(s) this certificate is valid.
+	DomainKey string `json:"domain"`
+
+	// Indicates at which point in time this certificate is no longer valid.
 	NotAfter time.Time `json:"not_after"`
+
+	// The encoded private key.
 	PrivateKeyEncoded string `json:"private_key"`
+
+	// The PEM-encoded certificate.
 	Certificate []byte `json:"certificate"`
+
+	// The CSR provided when we requested the certificate.
 	CSR []byte `json:"csr"`
 }
 
@@ -27,7 +38,7 @@ type CertificatesCache struct {
 	// The certificate to use as a fallback if all else fails.
 	FallbackCertificate *CertificateWrapper
 
-	// Mapping of domain name to certificate.
+	// Mapping of a domain's domain key to the certificate.
 	Certificates map[string]CertificateWrapper
 }
 
@@ -83,7 +94,7 @@ func (c *CertificatesCache) FlushToDisk(path string) {
 }
 
 func (c *CertificatesCache) AddCert(cert CertificateWrapper, path string) {
-	c.Certificates[cert.Domain] = cert
+	c.Certificates[cert.DomainKey] = cert
 	c.FlushToDisk(path)
 }
 
@@ -105,7 +116,7 @@ func CertificateCacheFromFile(path string) (CertificatesCache, error) {
 	certs := make(map[string]CertificateWrapper)
 	for _, cert := range store.Certificates {
 		cert.initTlsCertificate()
-		certs[cert.Domain] = cert
+		certs[cert.DomainKey] = cert
 	}
 	cache.Certificates = certs
 

internal/server/tls.go

@@ -43,10 +43,30 @@ func unlockDomain(domain string) {
 	delete(workingDomains, domain)
 }
 
+func buildDomainList(domain, pagesDomain string) []string {
+	if domain == pagesDomain || strings.HasSuffix(domain, pagesDomain) {
+		return []string{
+			pagesDomain,
+			"*." + pagesDomain,
+		}
+	}
+
+	return []string{domain}
+}
+
+func getDomainKey(domain, pagesDomain string) string {
+	if domain == pagesDomain || strings.HasSuffix(domain, pagesDomain) {
+		return "*." + pagesDomain
+	}
+
+	return domain
+}
+
 func MakeTlsConfig(pagesDomain, cachePath string, cache *certificates.CertificatesCache, acmeClient *lego.Client, giteaClient *gitea.Client) *tls.Config {
 	return &tls.Config{
 		GetCertificate: func(info *tls.ClientHelloInfo) (*tls.Certificate, error) {
 			// Validate that we should even care about this domain
+			isPagesDomain := info.ServerName == pagesDomain
 			cname := ""
 			if !strings.HasSuffix(info.ServerName, pagesDomain) {
 				// Note: We do not check err here because err != nil
@@ -59,33 +79,27 @@ func MakeTlsConfig(pagesDomain, cachePath string, cache *certificates.Certificat
 				}
 			}
 
-			// If we want to access <user>.<pages domain>, then we can just
-			// use a wildcard certificate.
-			domain := info.ServerName
-			/*if strings.HasSuffix(info.ServerName, pagesDomain) {
-				domain = "*." + pagesDomain
-			}*/
-
 			// Figure out a username for later username checks
 			username := ""
 			if cname == "" {
 				// domain ends on pagesDomain
-				username = strings.Split(domain, ".")[0]
+				username = strings.Split(info.ServerName, ".")[0]
 			} else {
 				// cname ends on pagesDomain
 				username = strings.Split(cname, ".")[0]
 			}
 
 			// Find the correct certificate
-			cert, found := cache.Certificates[info.ServerName]
+			domainKey := getDomainKey(info.ServerName, pagesDomain)
+			cert, found := cache.Certificates[domainKey]
 			if found {
 				if cert.IsValid() {
 					return cert.TlsCertificate, nil
 				} else {
-					if !repo.CanRequestCertificate(username, giteaClient) {
+					if !isPagesDomain && !repo.CanRequestCertificate(username, giteaClient) {
 						log.Warnf(
 							"Cannot renew certificate for %s because CanRequestCertificate(%s) returned false",
-							domain,
+							info.ServerName,
 							username,
 						)
 						return cert.TlsCertificate, nil
@@ -93,16 +107,16 @@ func MakeTlsConfig(pagesDomain, cachePath string, cache *certificates.Certificat
 
 					// If we're already working on the domain,
 					// return the old certificate
-					if lockIfUnlockedDomain(domain) {
+					if lockIfUnlockedDomain(domainKey) {
 						return cert.TlsCertificate, nil
 					}
-					defer unlockDomain(domain)
+					defer unlockDomain(domainKey)
 
 					// Renew the certificate
-					log.Infof("Certificate for %s expired, renewing", domain)
+					log.Infof("Certificate for %s expired, renewing", info.ServerName)
 					newCert, err := certificates.RenewCertificate(&cert, acmeClient)
 					if err != nil {
-						log.Errorf("Failed to renew certificate for %s: %v", domain, err)
+						log.Errorf("Failed to renew certificate for %s: %v", info.ServerName, err)
 						return cert.TlsCertificate, nil
 					}
 
@@ -111,31 +125,33 @@ func MakeTlsConfig(pagesDomain, cachePath string, cache *certificates.Certificat
 					return newCert.TlsCertificate, nil
 				}
 			} else {
-				if !repo.CanRequestCertificate(username, giteaClient) {
+				if !isPagesDomain && !repo.CanRequestCertificate(username, giteaClient) {
 					log.Warnf(
 						"Cannot request certificate for %s because CanRequestCertificate(%s) returned false",
-						domain,
+						info.ServerName,
 						username,
 					)
 					return cache.FallbackCertificate.TlsCertificate, nil
 				}
 
 				// Don't request if we're already requesting.
-				if lockIfUnlockedDomain(domain) {
+				key := getDomainKey(info.ServerName, pagesDomain)
+				if lockIfUnlockedDomain(domainKey) {
 					return cache.FallbackCertificate.TlsCertificate, nil
 				}
-				defer unlockDomain(domain)
+				defer unlockDomain(key)
 
 				// Request new certificate
-				log.Infof("Obtaining new certificate for %s...", domain)
+				log.Infof("Obtaining new certificate for %s...", info.ServerName)
 				cert, err := certificates.ObtainNewCertificate(
-					[]string{domain},
+					buildDomainList(info.ServerName, pagesDomain),
+					domainKey,
 					acmeClient,
 				)
 				if err != nil {
 					log.Errorf(
 						"Failed to get certificate for %s: %v",
-						domain,
+						info.ServerName,
 						err,
 					)
 					return cache.FallbackCertificate.TlsCertificate, nil

internal/server/tls_test.go

@@ -0,0 +1,69 @@
+package server
+
+import (
+	"testing"
+)
+
+const (
+	pagesDomain         = "pages.local"
+	pagesDomainWildcard = "*.pages.local"
+)
+
+func equals(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+
+	for i, _ := range a {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+
+	return true
+}
+
+func TestDomainListBare(t *testing.T) {
+	expect := []string{pagesDomain, pagesDomainWildcard}
+	res := buildDomainList(pagesDomain, pagesDomain)
+	if !equals(res, expect) {
+		t.Fatalf("%v != %v", res, expect)
+	}
+}
+
+func TestDomainListSubdomain(t *testing.T) {
+	expect := []string{pagesDomain, pagesDomainWildcard}
+	res := buildDomainList("user."+pagesDomain, pagesDomain)
+	if !equals(res, expect) {
+		t.Fatalf("%v != %v", res, expect)
+	}
+}
+
+func TestDomainListCNAME(t *testing.T) {
+	expect := []string{"testdomain.example"}
+	res := buildDomainList("testdomain.example", pagesDomain)
+	if !equals(res, expect) {
+		t.Fatalf("%v != %v", res, expect)
+	}
+}
+
+func TestDomainKeyBare(t *testing.T) {
+	res := getDomainKey(pagesDomain, pagesDomain)
+	if res != pagesDomainWildcard {
+		t.Fatalf("%s != %s", res, pagesDomainWildcard)
+	}
+}
+
+func TestDomainKeySubdomain(t *testing.T) {
+	res := getDomainKey("user."+pagesDomain, pagesDomain)
+	if res != pagesDomainWildcard {
+		t.Fatalf("%s != %s", res, pagesDomainWildcard)
+	}
+}
+
+func TestDomainKeyCNAME(t *testing.T) {
+	res := getDomainKey("testdomain.example", pagesDomain)
+	if res != "testdomain.example" {
+		t.Fatalf("%s != %s", res, "testdomain.example")
+	}
+}