diff --git a/context.go b/context.go index a97dd4096a..3b08dfc854 100644 --- a/context.go +++ b/context.go @@ -757,10 +757,14 @@ func (c *Context) ClientIP() string { } } - remoteIP, trusted := c.RemoteIP() + // It also checks if the remoteIP is a trusted proxy or not. + // In order to perform this validation, it will see if the IP is contained within at least one of the CIDR blocks + // defined by Engine.SetTrustedProxies() + remoteIP := net.ParseIP(c.RemoteIP()) if remoteIP == nil { return "" } + trusted := c.engine.isTrustedProxy(remoteIP) if trusted && c.engine.ForwardedByClientIP && c.engine.RemoteIPHeaders != nil { for _, headerName := range c.engine.RemoteIPHeaders { @@ -773,53 +777,13 @@ func (c *Context) ClientIP() string { return remoteIP.String() } -func (e *Engine) isTrustedProxy(ip net.IP) bool { - if e.trustedCIDRs != nil { - for _, cidr := range e.trustedCIDRs { - if cidr.Contains(ip) { - return true - } - } - } - return false -} - // RemoteIP parses the IP from Request.RemoteAddr, normalizes and returns the IP (without the port). -// It also checks if the remoteIP is a trusted proxy or not. -// In order to perform this validation, it will see if the IP is contained within at least one of the CIDR blocks -// defined by Engine.SetTrustedProxies() -func (c *Context) RemoteIP() (net.IP, bool) { +func (c *Context) RemoteIP() string { ip, _, err := net.SplitHostPort(strings.TrimSpace(c.Request.RemoteAddr)) if err != nil { - return nil, false - } - remoteIP := net.ParseIP(ip) - if remoteIP == nil { - return nil, false - } - - return remoteIP, c.engine.isTrustedProxy(remoteIP) -} - -func (e *Engine) validateHeader(header string) (clientIP string, valid bool) { - if header == "" { - return "", false - } - items := strings.Split(header, ",") - for i := len(items) - 1; i >= 0; i-- { - ipStr := strings.TrimSpace(items[i]) - ip := net.ParseIP(ipStr) - if ip == nil { - return "", false - } - - // X-Forwarded-For is appended by proxy - // Check IPs in reverse order and stop when find untrusted proxy - if (i == 0) || (!e.isTrustedProxy(ip)) { - return ipStr, true - } + return "" } - return + return ip } // ContentType returns the Content-Type header of the request. diff --git a/context_test.go b/context_test.go index c286c0f4cb..4d002c2375 100644 --- a/context_test.go +++ b/context_test.go @@ -12,6 +12,7 @@ import ( "html/template" "io" "mime/multipart" + "net" "net/http" "net/http/httptest" "os" @@ -1404,6 +1405,11 @@ func TestContextClientIP(t *testing.T) { // Tests exercising the TrustedProxies functionality resetContextForClientIPTests(c) + // IPv6 support + c.Request.RemoteAddr = "[::1]:12345" + assert.Equal(t, "20.20.20.20", c.ClientIP()) + + resetContextForClientIPTests(c) // No trusted proxies _ = c.engine.SetTrustedProxies([]string{}) c.engine.RemoteIPHeaders = []string{"X-Forwarded-For"} @@ -1500,6 +1506,7 @@ func resetContextForClientIPTests(c *Context) { c.Request.Header.Set("CF-Connecting-IP", "60.60.60.60") c.Request.RemoteAddr = " 40.40.40.40:42123 " c.engine.TrustedPlatform = "" + c.engine.trustedCIDRs = defaultTrustedCIDRs c.engine.AppEngine = false } @@ -2051,7 +2058,8 @@ func TestRemoteIPFail(t *testing.T) { c, _ := CreateTestContext(httptest.NewRecorder()) c.Request, _ = http.NewRequest("POST", "/", nil) c.Request.RemoteAddr = "[:::]:80" - ip, trust := c.RemoteIP() + ip := net.ParseIP(c.RemoteIP()) + trust := c.engine.isTrustedProxy(ip) assert.Nil(t, ip) assert.False(t, trust) } diff --git a/gin.go b/gin.go index 21513c6826..b0a5887752 100644 --- a/gin.go +++ b/gin.go @@ -11,7 +11,6 @@ import ( "net/http" "os" "path" - "reflect" "strings" "sync" @@ -28,7 +27,16 @@ var ( var defaultPlatform string -var defaultTrustedCIDRs = []*net.IPNet{{IP: net.IP{0x0, 0x0, 0x0, 0x0}, Mask: net.IPMask{0x0, 0x0, 0x0, 0x0}}} // 0.0.0.0/0 +var defaultTrustedCIDRs = []*net.IPNet{ + { // 0.0.0.0/0 (IPv4) + IP: net.IP{0x0, 0x0, 0x0, 0x0}, + Mask: net.IPMask{0x0, 0x0, 0x0, 0x0}, + }, + { // ::/0 (IPv6) + IP: net.IP{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, + Mask: net.IPMask{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, + }, +} // HandlerFunc defines the handler used by gin middleware as return value. type HandlerFunc func(*Context) @@ -399,9 +407,9 @@ func (engine *Engine) SetTrustedProxies(trustedProxies []string) error { return engine.parseTrustedProxies() } -// isUnsafeTrustedProxies compares Engine.trustedCIDRs and defaultTrustedCIDRs, it's not safe if equal (returns true) +// isUnsafeTrustedProxies checks if Engine.trustedCIDRs contains all IPs, it's not safe if it has (returns true) func (engine *Engine) isUnsafeTrustedProxies() bool { - return reflect.DeepEqual(engine.trustedCIDRs, defaultTrustedCIDRs) + return engine.isTrustedProxy(net.ParseIP("0.0.0.0")) || engine.isTrustedProxy(net.ParseIP("::")) } // parseTrustedProxies parse Engine.trustedProxies to Engine.trustedCIDRs @@ -411,6 +419,41 @@ func (engine *Engine) parseTrustedProxies() error { return err } +// isTrustedProxy will check whether the IP address is included in the trusted list according to Engine.trustedCIDRs +func (engine *Engine) isTrustedProxy(ip net.IP) bool { + if engine.trustedCIDRs == nil { + return false + } + for _, cidr := range engine.trustedCIDRs { + if cidr.Contains(ip) { + return true + } + } + return false +} + +// validateHeader will parse X-Forwarded-For header and return the trusted client IP address +func (engine *Engine) validateHeader(header string) (clientIP string, valid bool) { + if header == "" { + return "", false + } + items := strings.Split(header, ",") + for i := len(items) - 1; i >= 0; i-- { + ipStr := strings.TrimSpace(items[i]) + ip := net.ParseIP(ipStr) + if ip == nil { + break + } + + // X-Forwarded-For is appended by proxy + // Check IPs in reverse order and stop when find untrusted proxy + if (i == 0) || (!engine.isTrustedProxy(ip)) { + return ipStr, true + } + } + return "", false +} + // parseIP parse a string representation of an IP and returns a net.IP with the // minimum byte representation or nil if input is invalid. func parseIP(ip string) net.IP {