api/dns: init

6 files changed, 121 insertions, 15 deletions

diff --git a/api/dns.go b/api/dns.go
new file mode 100644
index 0000000..f8d345c
--- /dev/null
+++ b/api/dns.go
@@ -0,0 +1,64 @@
+package api
+
+import (
+	"encoding/json"
+	"log"
+	"net"
+
+	"sinanmohd.com/redq/dns"
+)
+
+type DnsResp map[string]string
+
+func handleDnsBlock(conn net.Conn, d *dns.Dns, domains []string) {
+	resp := make(DnsResp)
+
+	for _, domain := range domains {
+		err := d.Block(domain)
+		if err != nil {
+			resp[domain] = err.Error()
+		} else {
+			resp[domain] = "blocked"
+		}
+	}
+
+	buf, err := json.Marshal(resp)
+	if err != nil {
+		log.Printf("marshaling json: %s", err)
+		return
+	}
+
+	conn.Write(buf)
+}
+
+func handleDnsUnblock(conn net.Conn, d *dns.Dns, domains []string) {
+	resp := make(DnsResp)
+
+	for _, domain := range domains {
+		err := d.Unblock(domain)
+		if err != nil {
+			resp[domain] = err.Error()
+		} else {
+			resp[domain] = "unblocked"
+		}
+	}
+
+	buf, err := json.Marshal(resp)
+	if err != nil {
+		log.Printf("marshaling json: %s", err)
+		return
+	}
+
+	conn.Write(buf)
+}
+
+func handleDns(conn net.Conn, d *dns.Dns, domains []string, action string) {
+	switch action {
+	case "block":
+		handleDnsBlock(conn, d, domains)
+	case "unblock":
+		handleDnsUnblock(conn, d, domains)
+	default:
+		log.Printf("handling dns: invalid action '%s'", action)
+	}
+}
diff --git a/api/main.go b/api/main.go
index 32f7d08..eb8715f 100644
--- a/api/main.go
+++ b/api/main.go
@@ -7,6 +7,7 @@ import (
 	"net"
 
 	"sinanmohd.com/redq/db"
+	"sinanmohd.com/redq/dns"
 	"sinanmohd.com/redq/usage"
 )
 
@@ -16,9 +17,9 @@ const (
 )
 
 type ApiReq struct {
-	Type   string `json:"type"`
-	Action string `json:"action"`
-	Arg    string `json:"arg"`
+	Type   string   `json:"type"`
+	Action string   `json:"action"`
+	Arg    []string `json:"arg"`
 }
 
 type Api struct {
@@ -42,7 +43,7 @@ func New() (*Api, error) {
 	return &a, nil
 }
 
-func (a *Api) Run(u *usage.Usage, queries *db.Queries, ctxDb context.Context) {
+func (a *Api) Run(u *usage.Usage, d *dns.Dns, queries *db.Queries, ctxDb context.Context) {
 	for {
 		conn, err := a.sock.Accept()
 		if err != nil {
@@ -50,11 +51,11 @@ func (a *Api) Run(u *usage.Usage, queries *db.Queries, ctxDb context.Context) {
 			continue
 		}
 
-		go handleConn(conn, u, queries, ctxDb)
+		go handleConn(conn, u, d, queries, ctxDb)
 	}
 }
 
-func handleConn(conn net.Conn, u *usage.Usage, queries *db.Queries, ctxDb context.Context) {
+func handleConn(conn net.Conn, u *usage.Usage, d *dns.Dns, queries *db.Queries, ctxDb context.Context) {
 	defer conn.Close()
 	var req ApiReq
 	buf := make([]byte, bufSize)
@@ -76,6 +77,8 @@ func handleConn(conn net.Conn, u *usage.Usage, queries *db.Queries, ctxDb contex
 		handleBandwidth(conn, u)
 	case "usage":
 		handleUsage(conn, u, queries, ctxDb)
+	case "dns":
+		handleDns(conn, d, req.Arg, req.Action)
 	default:
 		log.Printf("invalid request type: %s", req.Type)
 	}
diff --git a/cmd/main.go b/cmd/main.go
index 540f9da..db9cc13 100644
--- a/cmd/main.go
+++ b/cmd/main.go
@@ -54,5 +54,5 @@ func main() {
 	go u.Run(iface, queries, ctx)
 	go d.Run()
 
-	a.Run(u, queries, ctx)
+	a.Run(u, d, queries, ctx)
 }
diff --git a/db/query.sql b/db/query.sql
index 9ba172f..f4b17dd 100644
--- a/db/query.sql
+++ b/db/query.sql
@@ -6,8 +6,7 @@ INSERT INTO Usage (
 );
 
 -- name: GetUsage :one
-SELECT SUM(Ingress) AS Ingress, SUM(Egress) AS Egress
-FROM Usage;
+SELECT SUM(Ingress) AS Ingress, SUM(Egress) AS Egress FROM Usage;
 
 -- name: EnterDnsBlackList :exec
 INSERT INTO DnsBlackList (
@@ -16,6 +15,9 @@ INSERT INTO DnsBlackList (
   $1
 );
 
+-- name: DeleteDnsBlackList :exec
+DELETE FROM DnsBlackList
+WHERE Name = $1;
+
 -- name: GetDnsBlackList :many
-SELECT *
-FROM DnsBlackList;
+SELECT * FROM DnsBlackList;
diff --git a/db/query.sql.go b/db/query.sql.go
index 80c6469..7c28723 100644
--- a/db/query.sql.go
+++ b/db/query.sql.go
@@ -11,6 +11,16 @@ import (
 	"github.com/jackc/pgx/v5/pgtype"
 )
 
+const deleteDnsBlackList = `-- name: DeleteDnsBlackList :exec
+DELETE FROM DnsBlackList
+WHERE Name = $1
+`
+
+func (q *Queries) DeleteDnsBlackList(ctx context.Context, name string) error {
+	_, err := q.db.Exec(ctx, deleteDnsBlackList, name)
+	return err
+}
+
 const enterDnsBlackList = `-- name: EnterDnsBlackList :exec
 INSERT INTO DnsBlackList (
   Name
@@ -52,8 +62,7 @@ func (q *Queries) EnterUsage(ctx context.Context, arg EnterUsageParams) error {
 }
 
 const getDnsBlackList = `-- name: GetDnsBlackList :many
-SELECT name
-FROM DnsBlackList
+SELECT name FROM DnsBlackList
 `
 
 func (q *Queries) GetDnsBlackList(ctx context.Context) ([]string, error) {
@@ -77,8 +86,7 @@ func (q *Queries) GetDnsBlackList(ctx context.Context) ([]string, error) {
 }
 
 const getUsage = `-- name: GetUsage :one
-SELECT SUM(Ingress) AS Ingress, SUM(Egress) AS Egress
-FROM Usage
+SELECT SUM(Ingress) AS Ingress, SUM(Egress) AS Egress FROM Usage
 `
 
 type GetUsageRow struct {
diff --git a/dns/main.go b/dns/main.go
index a9be24e..3daa879 100644
--- a/dns/main.go
+++ b/dns/main.go
@@ -37,6 +37,7 @@ func (d *Dns) ServeDNS(w dns.ResponseWriter, req *dns.Msg) {
 		resp = new(dns.Msg)
 		resp.SetReply(req)
 		w.WriteMsg(resp)
+		d.blackList.mutex.RUnlock()
 		return
 	}
 	d.blackList.mutex.RUnlock()
@@ -92,3 +93,31 @@ func New(queries *db.Queries, ctxDb context.Context) (*Dns, error) {
 func (d *Dns) Run() {
 	d.server.ListenAndServe()
 }
+
+func (d *Dns) Block(domain string) error {
+	err := d.queries.EnterDnsBlackList(d.ctxDb, domain)
+	if err != nil {
+		log.Printf("adding dns blacklist entry: %s", err)
+		return err
+	}
+
+	d.blackList.mutex.Lock()
+	d.blackList.data[domain] = true
+	d.blackList.mutex.Unlock()
+
+	return nil
+}
+
+func (d *Dns) Unblock(domain string) error {
+	err := d.queries.DeleteDnsBlackList(d.ctxDb, domain)
+	if err != nil {
+		log.Printf("deleting dns blacklist entry: %s", err)
+		return err
+	}
+
+	d.blackList.mutex.Lock()
+	delete(d.blackList.data, domain)
+	d.blackList.mutex.Unlock()
+
+	return nil
+}