godoor/wiegand.go

136 lines
2.6 KiB
Go

package main
import (
"encoding/binary"
"encoding/hex"
"fmt"
"golang.org/x/crypto/scrypt"
"time"
)
import (
"github.com/warthog618/gpiod"
)
type Wiegand struct {
aLine *gpiod.Line
bLine *gpiod.Line
bits [64]bool
bitNr int
bitTimeout time.Duration
bitTimeoutTimer *time.Timer
solenoidLine *gpiod.Line
}
func (w *Wiegand) OpenDoor() {
fmt.Println("Open")
w.solenoidLine.SetValue(1)
d, _ := time.ParseDuration("500ms")
time.Sleep(d)
w.solenoidLine.SetValue(0)
fmt.Println("Close")
}
func printCardId(card uint64) {
for i := 0; i < 7; i++ {
fmt.Printf("%02x", (card>>(8*i))&0xff)
}
fmt.Printf("\n")
}
func (w *Wiegand) cardRunner(validUids ValidUids) {
for {
// Wait for bit timeout
fmt.Printf("Waiting for bit timeout\n")
<-w.bitTimeoutTimer.C
fmt.Printf("\n")
if w.bitNr != 64 {
fmt.Printf("We got less than 64 bits: %d\n", w.bitNr)
}
var card uint64 = 0
for i := 63; i != 0; i-- {
if w.bits[i] == true {
card |= 1 << (63 - i)
}
}
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
}
}
func (w *Wiegand) wiegandAEvent(evt gpiod.LineEvent) {
w.bitTimeoutTimer.Reset(w.bitTimeout)
w.bits[w.bitNr] = false
fmt.Printf("0")
w.bitNr += 1
}
func (w *Wiegand) wiegandBEvent(evt gpiod.LineEvent) {
w.bitTimeoutTimer.Reset(w.bitTimeout)
w.bits[w.bitNr] = true
fmt.Printf("1")
w.bitNr += 1
}
func WiegandSetup(a int, b int, bitTimeout time.Duration, solenoid int) *Wiegand {
var wiegand Wiegand
wiegand.bitTimeout = bitTimeout
wiegand.bitTimeoutTimer = time.NewTimer(wiegand.bitTimeout)
if !wiegand.bitTimeoutTimer.Stop() {
<-wiegand.bitTimeoutTimer.C
}
wa, err := gpiod.RequestLine("gpiochip0", a, gpiod.AsInput,
gpiod.WithFallingEdge, gpiod.WithEventHandler(wiegand.wiegandAEvent))
if err != nil {
panic(err)
}
wiegand.aLine = wa
wb, err := gpiod.RequestLine("gpiochip0", b, gpiod.AsInput,
gpiod.WithFallingEdge, gpiod.WithEventHandler(wiegand.wiegandBEvent))
if err != nil {
panic(err)
}
wiegand.bLine = wb
solenoidLine, err := gpiod.RequestLine("gpiochip0", solenoid, gpiod.AsOutput(0))
if err != nil {
panic(err)
}
wiegand.solenoidLine = solenoidLine
return &wiegand
}
func (w *Wiegand) WiegandClose() {
w.aLine.Close()
w.bLine.Close()
w.solenoidLine.Close()
}