From 9857024c5dc3d8db9becceae7d7231b105bec2b4 Mon Sep 17 00:00:00 2001
From: Simon Zolin <s.zolin@adguard.com>
Date: Fri, 19 Jul 2019 15:14:19 +0300
Subject: [PATCH] + control: add /rewrite/* handlers

---
 home/control.go      |   1 +
 home/dns_rewrites.go | 107 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 108 insertions(+)
 create mode 100644 home/dns_rewrites.go

diff --git a/home/control.go b/home/control.go
index b012f9e9..daaf5dbd 100644
--- a/home/control.go
+++ b/home/control.go
@@ -1021,6 +1021,7 @@ func registerControlHandlers() {
 
 	RegisterTLSHandlers()
 	RegisterClientsHandlers()
+	registerRewritesHandlers()
 
 	http.HandleFunc("/dns-query", postInstall(handleDOH))
 }
diff --git a/home/dns_rewrites.go b/home/dns_rewrites.go
new file mode 100644
index 00000000..816739ab
--- /dev/null
+++ b/home/dns_rewrites.go
@@ -0,0 +1,107 @@
+package home
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/AdguardTeam/AdGuardHome/dnsfilter"
+	"github.com/AdguardTeam/golibs/log"
+)
+
+type rewriteEntryJSON struct {
+	Domain string `json:"domain"`
+	Answer string `json:"answer"`
+}
+
+func handleRewriteList(w http.ResponseWriter, r *http.Request) {
+	log.Tracef("%s %v", r.Method, r.URL)
+
+	arr := []*rewriteEntryJSON{}
+
+	config.RLock()
+	for _, ent := range config.DNS.Rewrites {
+		jsent := rewriteEntryJSON{
+			Domain: ent.Domain,
+			Answer: ent.Answer,
+		}
+		arr = append(arr, &jsent)
+	}
+	config.RUnlock()
+
+	w.Header().Set("Content-Type", "application/json")
+	err := json.NewEncoder(w).Encode(arr)
+	if err != nil {
+		httpError(w, http.StatusInternalServerError, "json.Encode: %s", err)
+		return
+	}
+}
+
+func handleRewriteAdd(w http.ResponseWriter, r *http.Request) {
+	log.Tracef("%s %v", r.Method, r.URL)
+
+	jsent := rewriteEntryJSON{}
+	err := json.NewDecoder(r.Body).Decode(&jsent)
+	if err != nil {
+		httpError(w, http.StatusBadRequest, "json.Decode: %s", err)
+		return
+	}
+
+	ent := dnsfilter.RewriteEntry{
+		Domain: jsent.Domain,
+		Answer: jsent.Answer,
+	}
+	config.Lock()
+	config.DNS.Rewrites = append(config.DNS.Rewrites, ent)
+	config.Unlock()
+	log.Debug("Rewrites: added element: %s -> %s [%d]",
+		ent.Domain, ent.Answer, len(config.DNS.Rewrites))
+
+	err = writeAllConfigsAndReloadDNS()
+	if err != nil {
+		httpError(w, http.StatusBadRequest, "%s", err)
+		return
+	}
+
+	returnOK(w)
+}
+
+func handleRewriteDelete(w http.ResponseWriter, r *http.Request) {
+	log.Tracef("%s %v", r.Method, r.URL)
+
+	jsent := rewriteEntryJSON{}
+	err := json.NewDecoder(r.Body).Decode(&jsent)
+	if err != nil {
+		httpError(w, http.StatusBadRequest, "json.Decode: %s", err)
+		return
+	}
+
+	entDel := dnsfilter.RewriteEntry{
+		Domain: jsent.Domain,
+		Answer: jsent.Answer,
+	}
+	arr := []dnsfilter.RewriteEntry{}
+	config.Lock()
+	for _, ent := range config.DNS.Rewrites {
+		if ent == entDel {
+			log.Debug("Rewrites: removed element: %s -> %s", ent.Domain, ent.Answer)
+			continue
+		}
+		arr = append(arr, ent)
+	}
+	config.DNS.Rewrites = arr
+	config.Unlock()
+
+	err = writeAllConfigsAndReloadDNS()
+	if err != nil {
+		httpError(w, http.StatusBadRequest, "%s", err)
+		return
+	}
+
+	returnOK(w)
+}
+
+func registerRewritesHandlers() {
+	http.HandleFunc("/control/rewrite/list", postInstall(optionalAuth(ensureGET(handleRewriteList))))
+	http.HandleFunc("/control/rewrite/add", postInstall(optionalAuth(ensurePOST(handleRewriteAdd))))
+	http.HandleFunc("/control/rewrite/delete", postInstall(optionalAuth(ensurePOST(handleRewriteDelete))))
+}