diff options
Diffstat (limited to 'src/pkg/crypto/tls/common.go')
| -rw-r--r-- | src/pkg/crypto/tls/common.go | 151 |
1 files changed, 111 insertions, 40 deletions
diff --git a/src/pkg/crypto/tls/common.go b/src/pkg/crypto/tls/common.go index 8fb1a8848..25f7a920c 100644 --- a/src/pkg/crypto/tls/common.go +++ b/src/pkg/crypto/tls/common.go @@ -5,11 +5,11 @@ package tls import ( + "crypto" "crypto/rand" - "crypto/rsa" "crypto/x509" "io" - "io/ioutil" + "strings" "sync" "time" ) @@ -101,12 +101,28 @@ type ConnectionState struct { NegotiatedProtocol string NegotiatedProtocolIsMutual bool + // ServerName contains the server name indicated by the client, if any. + // (Only valid for server connections.) + ServerName string + // the certificate chain that was presented by the other side PeerCertificates []*x509.Certificate // the verified certificate chains built from PeerCertificates. VerifiedChains [][]*x509.Certificate } +// ClientAuthType declares the policy the server will follow for +// TLS Client Authentication. +type ClientAuthType int + +const ( + NoClientCert ClientAuthType = iota + RequestClientCert + RequireAnyClientCert + VerifyClientCertIfGiven + RequireAndVerifyClientCert +) + // A Config structure is used to configure a TLS client or server. After one // has been passed to a TLS function it must not be modified. type Config struct { @@ -116,14 +132,22 @@ type Config struct { Rand io.Reader // Time returns the current time as the number of seconds since the epoch. - // If Time is nil, TLS uses the system time.Seconds. - Time func() int64 + // If Time is nil, TLS uses time.Now. + Time func() time.Time // Certificates contains one or more certificate chains // to present to the other side of the connection. // Server configurations must include at least one certificate. Certificates []Certificate + // NameToCertificate maps from a certificate name to an element of + // Certificates. Note that a certificate name can be of the form + // '*.example.com' and so doesn't have to be a domain name as such. + // See Config.BuildNameToCertificate + // The nil value causes the first element of Certificates to be used + // for all connections. + NameToCertificate map[string]*Certificate + // RootCAs defines the set of root certificate authorities // that clients use when verifying server certificates. // If RootCAs is nil, TLS uses the host's root CA set. @@ -136,11 +160,22 @@ type Config struct { // hosting. ServerName string - // AuthenticateClient controls whether a server will request a certificate - // from the client. It does not require that the client send a - // certificate nor does it require that the certificate sent be - // anything more than self-signed. - AuthenticateClient bool + // ClientAuth determines the server's policy for + // TLS Client Authentication. The default is NoClientCert. + ClientAuth ClientAuthType + + // ClientCAs defines the set of root certificate authorities + // that servers use if required to verify a client certificate + // by the policy in ClientAuth. + ClientCAs *x509.CertPool + + // InsecureSkipVerify controls whether a client verifies the + // server's certificate chain and host name. + // If InsecureSkipVerify is true, TLS accepts any certificate + // presented by the server and any host name in that certificate. + // In this mode, TLS is susceptible to man-in-the-middle attacks. + // This should be used only for testing. + InsecureSkipVerify bool // CipherSuites is a list of supported cipher suites. If CipherSuites // is nil, TLS uses a list of suites supported by the implementation. @@ -155,10 +190,10 @@ func (c *Config) rand() io.Reader { return r } -func (c *Config) time() int64 { +func (c *Config) time() time.Time { t := c.Time if t == nil { - t = time.Seconds + t = time.Now } return t() } @@ -179,13 +214,71 @@ func (c *Config) cipherSuites() []uint16 { return s } +// getCertificateForName returns the best certificate for the given name, +// defaulting to the first element of c.Certificates if there are no good +// options. +func (c *Config) getCertificateForName(name string) *Certificate { + if len(c.Certificates) == 1 || c.NameToCertificate == nil { + // There's only one choice, so no point doing any work. + return &c.Certificates[0] + } + + name = strings.ToLower(name) + for len(name) > 0 && name[len(name)-1] == '.' { + name = name[:len(name)-1] + } + + if cert, ok := c.NameToCertificate[name]; ok { + return cert + } + + // try replacing labels in the name with wildcards until we get a + // match. + labels := strings.Split(name, ".") + for i := range labels { + labels[i] = "*" + candidate := strings.Join(labels, ".") + if cert, ok := c.NameToCertificate[candidate]; ok { + return cert + } + } + + // If nothing matches, return the first certificate. + return &c.Certificates[0] +} + +// BuildNameToCertificate parses c.Certificates and builds c.NameToCertificate +// from the CommonName and SubjectAlternateName fields of each of the leaf +// certificates. +func (c *Config) BuildNameToCertificate() { + c.NameToCertificate = make(map[string]*Certificate) + for i := range c.Certificates { + cert := &c.Certificates[i] + x509Cert, err := x509.ParseCertificate(cert.Certificate[0]) + if err != nil { + continue + } + if len(x509Cert.Subject.CommonName) > 0 { + c.NameToCertificate[x509Cert.Subject.CommonName] = cert + } + for _, san := range x509Cert.DNSNames { + c.NameToCertificate[san] = cert + } + } +} + // A Certificate is a chain of one or more certificates, leaf first. type Certificate struct { Certificate [][]byte - PrivateKey *rsa.PrivateKey + PrivateKey crypto.PrivateKey // supported types: *rsa.PrivateKey // OCSPStaple contains an optional OCSP response which will be served // to clients that request it. OCSPStaple []byte + // Leaf is the parsed form of the leaf certificate, which may be + // initialized using x509.ParseCertificate to reduce per-handshake + // processing for TLS clients doing client authentication. If nil, the + // leaf certificate will be parsed as needed. + Leaf *x509.Certificate } // A TLS record. @@ -218,15 +311,6 @@ func defaultConfig() *Config { return &emptyConfig } -// Possible certificate files; stop after finding one. -// On OS X we should really be using the Directory Services keychain -// but that requires a lot of Mach goo to get at. Instead we use -// the same root set that curl uses. -var certFiles = []string{ - "/etc/ssl/certs/ca-certificates.crt", // Linux etc - "/usr/share/curl/curl-ca-bundle.crt", // OS X -} - var once sync.Once func defaultRoots() *x509.CertPool { @@ -244,27 +328,14 @@ func initDefaults() { initDefaultCipherSuites() } -var varDefaultRoots *x509.CertPool - -func initDefaultRoots() { - roots := x509.NewCertPool() - for _, file := range certFiles { - data, err := ioutil.ReadFile(file) - if err == nil { - roots.AppendCertsFromPEM(data) - break - } - } - varDefaultRoots = roots -} - -var varDefaultCipherSuites []uint16 +var ( + varDefaultRoots *x509.CertPool + varDefaultCipherSuites []uint16 +) func initDefaultCipherSuites() { varDefaultCipherSuites = make([]uint16, len(cipherSuites)) - i := 0 - for id := range cipherSuites { - varDefaultCipherSuites[i] = id - i++ + for i, suite := range cipherSuites { + varDefaultCipherSuites[i] = suite.id } } |