diff --git a/go.mod b/go.mod
index 4cb4aff..4bc03e1 100644
--- a/go.mod
+++ b/go.mod
@@ -4,5 +4,6 @@ go 1.18
 
 require (
 	github.com/warthog618/gpiod v0.8.0 // indirect
-	golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae // indirect
+	golang.org/x/crypto v0.0.0-20220331220935-ae2d96664a29 // indirect
+	golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1 // indirect
 )
diff --git a/go.sum b/go.sum
index d8aee82..b809ab9 100644
--- a/go.sum
+++ b/go.sum
@@ -1,4 +1,8 @@
 github.com/warthog618/gpiod v0.8.0 h1:qxH9XVvWHpTxzWFSndBcujFyNH5zVRzHM63tcmm85o4=
 github.com/warthog618/gpiod v0.8.0/go.mod h1:a7Csa+IJtDBZ39++zC/6Srjo01qWejt/5velrDWuNkY=
+golang.org/x/crypto v0.0.0-20220331220935-ae2d96664a29 h1:tkVvjkPTB7pnW3jnid7kNyAMPVWllTNOf/qKDze4p9o=
+golang.org/x/crypto v0.0.0-20220331220935-ae2d96664a29/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae h1:/WDfKMnPU+m5M4xB+6x4kaepxRw6jWvR5iDRdvjHgy8=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1 h1:SrN+KX8Art/Sf4HNj6Zcz06G7VEz+7w9tdXTPOZ7+l4=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
diff --git a/godoor.go b/godoor.go
index 3ad4a87..d844af4 100644
--- a/godoor.go
+++ b/godoor.go
@@ -1,6 +1,11 @@
 package main
 
-import "fmt"
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+)
 import "time"
 
 const wiegand_a = 17
@@ -8,12 +13,56 @@ const wiegand_b = 18
 const wiegand_bit_timeout = time.Millisecond * 8
 const solenoid = 21
 
+type card struct {
+	UidHash string `json:"uid_hash"`
+}
+
+type cardToken struct {
+	Token card `json:"token"`
+}
+
+type cardList struct {
+	AllowedUids []cardToken `json:"allowed_uids"`
+}
+
+type ValidUids map[string]bool // bool has no meaning
+
 func main() {
 
 	wiegand := WiegandSetup(wiegand_a, wiegand_b, wiegand_bit_timeout, solenoid)
 
-	//openDoor(solenoid_line)
-	go wiegand.cardRunner()
+	client := http.Client{}
+	req, err := http.NewRequest(http.MethodGet, "urlrul", nil)
+	if err != nil {
+		panic(err)
+	}
+	req.Header.Add("KEY", "keykey")
+	resp, err := client.Do(req)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf("%v\n", resp)
+
+	var cl cardList
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		panic(err)
+	}
+
+	err = json.Unmarshal(body, &cl)
+	if err != nil {
+		panic(err)
+	}
+
+	validUids := make(ValidUids)
+	for i, val := range cl.AllowedUids {
+		fmt.Printf("%d: %+v\n", i, val.Token.UidHash)
+		validUids[val.Token.UidHash] = false
+	}
+
+	go wiegand.cardRunner(validUids)
+
 	fmt.Printf("Sleeping\n")
 
 	for {
diff --git a/wiegand.go b/wiegand.go
index 1fe1bdd..6e6aee1 100644
--- a/wiegand.go
+++ b/wiegand.go
@@ -1,7 +1,10 @@
 package main
 
 import (
+	"encoding/binary"
+	"encoding/hex"
 	"fmt"
+	"golang.org/x/crypto/scrypt"
 	"time"
 )
 
@@ -36,7 +39,7 @@ func printCardId(card uint64) {
 	fmt.Printf("\n")
 }
 
-func (w *Wiegand) cardRunner() {
+func (w *Wiegand) cardRunner(validUids ValidUids) {
 	for {
 		// Wait for bit timeout
 		fmt.Printf("Waiting for bit timeout\n")
@@ -56,6 +59,24 @@ func (w *Wiegand) cardRunner() {
 
 		printCardId(card)
 
+		b := make([]byte, 8)
+		binary.LittleEndian.PutUint64(b, card)
+		hashed, err := scrypt.Key(b, []byte("hashsah"), 16384, 8, 1, 64)
+		if err != nil {
+			panic(err)
+		}
+
+		hashedHex := hex.EncodeToString(hashed)
+		fmt.Println(hashedHex)
+
+		_, ok := validUids[hashedHex]
+		if ok {
+			fmt.Println("Opening door")
+			w.OpenDoor()
+		} else {
+			fmt.Println("Unknown card")
+		}
+
 		w.bitNr = 0
 	}
 }