diff --git a/README.md b/README.md
index 9fb2b54..e38fd7e 100644
--- a/README.md
+++ b/README.md
@@ -81,6 +81,7 @@ between IPv4 and IPv6 lookup.
* JSON output
* ASN, country and city lookup using the MaxMind GeoIP database
* Port testing
+* All endpoints (except `/port`) can return information about a custom IP address specified via `?ip=` query parameter
* Open source under the [BSD 3-Clause license](https://opensource.org/licenses/BSD-3-Clause)
## Why?
diff --git a/http/http.go b/http/http.go
index 7c9263a..b5d275d 100644
--- a/http/http.go
+++ b/http/http.go
@@ -69,15 +69,27 @@ func ipFromForwardedForHeader(v string) string {
return v[:sep]
}
-func ipFromRequest(headers []string, r *http.Request) (net.IP, error) {
+// ipFromRequest detects the IP address for this transaction.
+//
+// * `headers` - the specific HTTP headers to trust
+// * `r` - the incoming HTTP request
+// * `customIP` - whether to allow the IP to be pulled from query parameters
+func ipFromRequest(headers []string, r *http.Request, customIP bool) (net.IP, error) {
remoteIP := ""
- for _, header := range headers {
- remoteIP = r.Header.Get(header)
- if http.CanonicalHeaderKey(header) == "X-Forwarded-For" {
- remoteIP = ipFromForwardedForHeader(remoteIP)
+ if customIP && r.URL != nil {
+ if v, ok := r.URL.Query()["ip"]; ok {
+ remoteIP = v[0]
}
- if remoteIP != "" {
- break
+ }
+ if remoteIP == "" {
+ for _, header := range headers {
+ remoteIP = r.Header.Get(header)
+ if http.CanonicalHeaderKey(header) == "X-Forwarded-For" {
+ remoteIP = ipFromForwardedForHeader(remoteIP)
+ }
+ if remoteIP != "" {
+ break
+ }
}
}
if remoteIP == "" {
@@ -105,7 +117,7 @@ func userAgentFromRequest(r *http.Request) *useragent.UserAgent {
}
func (s *Server) newResponse(r *http.Request) (Response, error) {
- ip, err := ipFromRequest(s.IPHeaders, r)
+ ip, err := ipFromRequest(s.IPHeaders, r, true)
if err != nil {
return Response{}, err
}
@@ -127,7 +139,6 @@ func (s *Server) newResponse(r *http.Request) (Response, error) {
if asn.AutonomousSystemNumber > 0 {
autonomousSystemNumber = fmt.Sprintf("AS%d", asn.AutonomousSystemNumber)
}
- userAgent := userAgentFromRequest(r)
response = &Response{
IP: ip,
IPDecimal: ipDecimal,
@@ -145,9 +156,9 @@ func (s *Server) newResponse(r *http.Request) (Response, error) {
ASN: autonomousSystemNumber,
ASNOrg: asn.AutonomousSystemOrganization,
Hostname: hostname,
- UserAgent: userAgent,
}
s.cache.Set(ip, response)
+ response.UserAgent = userAgentFromRequest(r)
return *response, nil
}
@@ -157,7 +168,7 @@ func (s *Server) newPortResponse(r *http.Request) (PortResponse, error) {
if err != nil || port < 1 || port > 65535 {
return PortResponse{Port: port}, fmt.Errorf("invalid port: %s", lastElement)
}
- ip, err := ipFromRequest(s.IPHeaders, r)
+ ip, err := ipFromRequest(s.IPHeaders, r, false)
if err != nil {
return PortResponse{Port: port}, err
}
@@ -170,7 +181,7 @@ func (s *Server) newPortResponse(r *http.Request) (PortResponse, error) {
}
func (s *Server) CLIHandler(w http.ResponseWriter, r *http.Request) *appError {
- ip, err := ipFromRequest(s.IPHeaders, r)
+ ip, err := ipFromRequest(s.IPHeaders, r, true)
if err != nil {
return internalServerError(err)
}
diff --git a/http/http_test.go b/http/http_test.go
index ab3a789..00e58a4 100644
--- a/http/http_test.go
+++ b/http/http_test.go
@@ -6,6 +6,7 @@ import (
"net"
"net/http"
"net/http/httptest"
+ "net/url"
"testing"
"github.com/mpolden/echoip/iputil/geo"
@@ -139,6 +140,8 @@ func TestJSONHandlers(t *testing.T) {
{s.URL + "/port/0", `{"error":"invalid port: 0"}`, 400},
{s.URL + "/port/65537", `{"error":"invalid port: 65537"}`, 400},
{s.URL + "/port/31337", `{"ip":"127.0.0.1","port":31337,"reachable":true}`, 200},
+ {s.URL + "/port/80", `{"ip":"127.0.0.1","port":80,"reachable":true}`, 200}, // checking that our test server is reachable on port 80
+ {s.URL + "/port/80?ip=1.3.3.7", `{"ip":"127.0.0.1","port":80,"reachable":true}`, 200}, // ensuring that the "ip" parameter is not usable to check remote host ports
{s.URL + "/foo", `{"error":"404 page not found"}`, 404},
{s.URL + "/health", `{"status":"OK"}`, 200},
}
@@ -165,22 +168,29 @@ func TestIPFromRequest(t *testing.T) {
trustedHeaders []string
out string
}{
- {"127.0.0.1:9999", "", "", nil, "127.0.0.1"}, // No header given
- {"127.0.0.1:9999", "X-Real-IP", "1.3.3.7", nil, "127.0.0.1"}, // Trusted header is empty
- {"127.0.0.1:9999", "X-Real-IP", "1.3.3.7", []string{"X-Foo-Bar"}, "127.0.0.1"}, // Trusted header does not match
- {"127.0.0.1:9999", "X-Real-IP", "1.3.3.7", []string{"X-Real-IP", "X-Forwarded-For"}, "1.3.3.7"}, // Trusted header matches
- {"127.0.0.1:9999", "X-Forwarded-For", "1.3.3.7", []string{"X-Real-IP", "X-Forwarded-For"}, "1.3.3.7"}, // Second trusted header matches
- {"127.0.0.1:9999", "X-Forwarded-For", "1.3.3.7,4.2.4.2", []string{"X-Forwarded-For"}, "1.3.3.7"}, // X-Forwarded-For with multiple entries (commas separator)
- {"127.0.0.1:9999", "X-Forwarded-For", "1.3.3.7, 4.2.4.2", []string{"X-Forwarded-For"}, "1.3.3.7"}, // X-Forwarded-For with multiple entries (space+comma separator)
- {"127.0.0.1:9999", "X-Forwarded-For", "", []string{"X-Forwarded-For"}, "127.0.0.1"}, // Empty header
+ {"127.0.0.1:9999", "", "", nil, "127.0.0.1"}, // No header given
+ {"127.0.0.1:9999", "X-Real-IP", "1.3.3.7", nil, "127.0.0.1"}, // Trusted header is empty
+ {"127.0.0.1:9999", "X-Real-IP", "1.3.3.7", []string{"X-Foo-Bar"}, "127.0.0.1"}, // Trusted header does not match
+ {"127.0.0.1:9999", "X-Real-IP", "1.3.3.7", []string{"X-Real-IP", "X-Forwarded-For"}, "1.3.3.7"}, // Trusted header matches
+ {"127.0.0.1:9999", "X-Forwarded-For", "1.3.3.7", []string{"X-Real-IP", "X-Forwarded-For"}, "1.3.3.7"}, // Second trusted header matches
+ {"127.0.0.1:9999", "X-Forwarded-For", "1.3.3.7,4.2.4.2", []string{"X-Forwarded-For"}, "1.3.3.7"}, // X-Forwarded-For with multiple entries (commas separator)
+ {"127.0.0.1:9999", "X-Forwarded-For", "1.3.3.7, 4.2.4.2", []string{"X-Forwarded-For"}, "1.3.3.7"}, // X-Forwarded-For with multiple entries (space+comma separator)
+ {"127.0.0.1:9999", "X-Forwarded-For", "", []string{"X-Forwarded-For"}, "127.0.0.1"}, // Empty header
+ {"127.0.0.1:9999?ip=1.2.3.4", "", "", nil, "1.2.3.4"}, // passed in "ip" parameter
+ {"127.0.0.1:9999?ip=1.2.3.4", "X-Forwarded-For", "1.3.3.7,4.2.4.2", []string{"X-Forwarded-For"}, "1.2.3.4"}, // ip parameter wins over X-Forwarded-For with multiple entries
}
for _, tt := range tests {
+ u, err := url.Parse("http://" + tt.remoteAddr)
+ if err != nil {
+ t.Fatal(err)
+ }
r := &http.Request{
- RemoteAddr: tt.remoteAddr,
+ RemoteAddr: u.Host,
Header: http.Header{},
+ URL: u,
}
r.Header.Add(tt.headerKey, tt.headerValue)
- ip, err := ipFromRequest(tt.trustedHeaders, r)
+ ip, err := ipFromRequest(tt.trustedHeaders, r, true)
if err != nil {
t.Fatal(err)
}
diff --git a/index.html b/index.html
index b26d8d3..95ac56b 100644
--- a/index.html
+++ b/index.html
@@ -135,6 +135,7 @@ $ http {{ .Host }}/asn
$ http {{ .Host }}/json
{{ .JSON }}
Setting the Accept: application/json header also works as expected.
+ All endpoints (except /port) can return information about a custom IP address specified via ?ip= query parameter.
Plain output
Always returns the IP address including a trailing newline, regardless of user agent.