diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/clientconn.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/clientconn.go | 181 |
1 files changed, 141 insertions, 40 deletions
diff --git a/vendor/google.golang.org/grpc/clientconn.go b/vendor/google.golang.org/grpc/clientconn.go index 34cc4c948..5a9e7d754 100644 --- a/vendor/google.golang.org/grpc/clientconn.go +++ b/vendor/google.golang.org/grpc/clientconn.go @@ -23,6 +23,7 @@ import ( "errors" "fmt" "math" + "net/url" "reflect" "strings" "sync" @@ -37,7 +38,6 @@ import ( "google.golang.org/grpc/internal/backoff" "google.golang.org/grpc/internal/channelz" "google.golang.org/grpc/internal/grpcsync" - "google.golang.org/grpc/internal/grpcutil" iresolver "google.golang.org/grpc/internal/resolver" "google.golang.org/grpc/internal/transport" "google.golang.org/grpc/keepalive" @@ -248,38 +248,15 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn * } // Determine the resolver to use. - cc.parsedTarget = grpcutil.ParseTarget(cc.target, cc.dopts.copts.Dialer != nil) - channelz.Infof(logger, cc.channelzID, "parsed scheme: %q", cc.parsedTarget.Scheme) - resolverBuilder := cc.getResolver(cc.parsedTarget.Scheme) - if resolverBuilder == nil { - // If resolver builder is still nil, the parsed target's scheme is - // not registered. Fallback to default resolver and set Endpoint to - // the original target. - channelz.Infof(logger, cc.channelzID, "scheme %q not registered, fallback to default scheme", cc.parsedTarget.Scheme) - cc.parsedTarget = resolver.Target{ - Scheme: resolver.GetDefaultScheme(), - Endpoint: target, - } - resolverBuilder = cc.getResolver(cc.parsedTarget.Scheme) - if resolverBuilder == nil { - return nil, fmt.Errorf("could not get resolver for default scheme: %q", cc.parsedTarget.Scheme) - } + resolverBuilder, err := cc.parseTargetAndFindResolver() + if err != nil { + return nil, err } - - creds := cc.dopts.copts.TransportCredentials - if creds != nil && creds.Info().ServerName != "" { - cc.authority = creds.Info().ServerName - } else if cc.dopts.insecure && cc.dopts.authority != "" { - cc.authority = cc.dopts.authority - } else if strings.HasPrefix(cc.target, "unix:") || strings.HasPrefix(cc.target, "unix-abstract:") { - cc.authority = "localhost" - } else if strings.HasPrefix(cc.parsedTarget.Endpoint, ":") { - cc.authority = "localhost" + cc.parsedTarget.Endpoint - } else { - // Use endpoint from "scheme://authority/endpoint" as the default - // authority for ClientConn. - cc.authority = cc.parsedTarget.Endpoint + cc.authority, err = determineAuthority(cc.parsedTarget.Endpoint, cc.target, cc.dopts) + if err != nil { + return nil, err } + channelz.Infof(logger, cc.channelzID, "Channel authority set to %q", cc.authority) if cc.dopts.scChan != nil && !scSet { // Blocking wait for the initial service config. @@ -902,10 +879,7 @@ func (ac *addrConn) tryUpdateAddrs(addrs []resolver.Address) bool { // ac.state is Ready, try to find the connected address. var curAddrFound bool for _, a := range addrs { - // a.ServerName takes precedent over ClientConn authority, if present. - if a.ServerName == "" { - a.ServerName = ac.cc.authority - } + a.ServerName = ac.cc.getServerName(a) if reflect.DeepEqual(ac.curAddr, a) { curAddrFound = true break @@ -919,6 +893,26 @@ func (ac *addrConn) tryUpdateAddrs(addrs []resolver.Address) bool { return curAddrFound } +// getServerName determines the serverName to be used in the connection +// handshake. The default value for the serverName is the authority on the +// ClientConn, which either comes from the user's dial target or through an +// authority override specified using the WithAuthority dial option. Name +// resolvers can specify a per-address override for the serverName through the +// resolver.Address.ServerName field which is used only if the WithAuthority +// dial option was not used. The rationale is that per-address authority +// overrides specified by the name resolver can represent a security risk, while +// an override specified by the user is more dependable since they probably know +// what they are doing. +func (cc *ClientConn) getServerName(addr resolver.Address) string { + if cc.dopts.authority != "" { + return cc.dopts.authority + } + if addr.ServerName != "" { + return addr.ServerName + } + return cc.authority +} + func getMethodConfig(sc *ServiceConfig, method string) MethodConfig { if sc == nil { return MethodConfig{} @@ -1275,11 +1269,7 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne prefaceReceived := grpcsync.NewEvent() connClosed := grpcsync.NewEvent() - // addr.ServerName takes precedent over ClientConn authority, if present. - if addr.ServerName == "" { - addr.ServerName = ac.cc.authority - } - + addr.ServerName = ac.cc.getServerName(addr) hctx, hcancel := context.WithCancel(ac.ctx) hcStarted := false // protected by ac.mu @@ -1621,3 +1611,114 @@ func (cc *ClientConn) connectionError() error { defer cc.lceMu.Unlock() return cc.lastConnectionError } + +func (cc *ClientConn) parseTargetAndFindResolver() (resolver.Builder, error) { + channelz.Infof(logger, cc.channelzID, "original dial target is: %q", cc.target) + + var rb resolver.Builder + parsedTarget, err := parseTarget(cc.target) + if err != nil { + channelz.Infof(logger, cc.channelzID, "dial target %q parse failed: %v", cc.target, err) + } else { + channelz.Infof(logger, cc.channelzID, "parsed dial target is: %+v", parsedTarget) + rb = cc.getResolver(parsedTarget.Scheme) + if rb != nil { + cc.parsedTarget = parsedTarget + return rb, nil + } + } + + // We are here because the user's dial target did not contain a scheme or + // specified an unregistered scheme. We should fallback to the default + // scheme, except when a custom dialer is specified in which case, we should + // always use passthrough scheme. + defScheme := resolver.GetDefaultScheme() + channelz.Infof(logger, cc.channelzID, "fallback to scheme %q", defScheme) + canonicalTarget := defScheme + ":///" + cc.target + + parsedTarget, err = parseTarget(canonicalTarget) + if err != nil { + channelz.Infof(logger, cc.channelzID, "dial target %q parse failed: %v", canonicalTarget, err) + return nil, err + } + channelz.Infof(logger, cc.channelzID, "parsed dial target is: %+v", parsedTarget) + rb = cc.getResolver(parsedTarget.Scheme) + if rb == nil { + return nil, fmt.Errorf("could not get resolver for default scheme: %q", parsedTarget.Scheme) + } + cc.parsedTarget = parsedTarget + return rb, nil +} + +// parseTarget uses RFC 3986 semantics to parse the given target into a +// resolver.Target struct containing scheme, authority and endpoint. Query +// params are stripped from the endpoint. +func parseTarget(target string) (resolver.Target, error) { + u, err := url.Parse(target) + if err != nil { + return resolver.Target{}, err + } + // For targets of the form "[scheme]://[authority]/endpoint, the endpoint + // value returned from url.Parse() contains a leading "/". Although this is + // in accordance with RFC 3986, we do not want to break existing resolver + // implementations which expect the endpoint without the leading "/". So, we + // end up stripping the leading "/" here. But this will result in an + // incorrect parsing for something like "unix:///path/to/socket". Since we + // own the "unix" resolver, we can workaround in the unix resolver by using + // the `URL` field instead of the `Endpoint` field. + endpoint := u.Path + if endpoint == "" { + endpoint = u.Opaque + } + endpoint = strings.TrimPrefix(endpoint, "/") + return resolver.Target{ + Scheme: u.Scheme, + Authority: u.Host, + Endpoint: endpoint, + URL: *u, + }, nil +} + +// Determine channel authority. The order of precedence is as follows: +// - user specified authority override using `WithAuthority` dial option +// - creds' notion of server name for the authentication handshake +// - endpoint from dial target of the form "scheme://[authority]/endpoint" +func determineAuthority(endpoint, target string, dopts dialOptions) (string, error) { + // Historically, we had two options for users to specify the serverName or + // authority for a channel. One was through the transport credentials + // (either in its constructor, or through the OverrideServerName() method). + // The other option (for cases where WithInsecure() dial option was used) + // was to use the WithAuthority() dial option. + // + // A few things have changed since: + // - `insecure` package with an implementation of the `TransportCredentials` + // interface for the insecure case + // - WithAuthority() dial option support for secure credentials + authorityFromCreds := "" + if creds := dopts.copts.TransportCredentials; creds != nil && creds.Info().ServerName != "" { + authorityFromCreds = creds.Info().ServerName + } + authorityFromDialOption := dopts.authority + if (authorityFromCreds != "" && authorityFromDialOption != "") && authorityFromCreds != authorityFromDialOption { + return "", fmt.Errorf("ClientConn's authority from transport creds %q and dial option %q don't match", authorityFromCreds, authorityFromDialOption) + } + + switch { + case authorityFromDialOption != "": + return authorityFromDialOption, nil + case authorityFromCreds != "": + return authorityFromCreds, nil + case strings.HasPrefix(target, "unix:") || strings.HasPrefix(target, "unix-abstract:"): + // TODO: remove when the unix resolver implements optional interface to + // return channel authority. + return "localhost", nil + case strings.HasPrefix(endpoint, ":"): + return "localhost" + endpoint, nil + default: + // TODO: Define an optional interface on the resolver builder to return + // the channel authority given the user's dial target. For resolvers + // which don't implement this interface, we will use the endpoint from + // "scheme://authority/endpoint" as the default authority. + return endpoint, nil + } +} |