diff --git a/client/src/mifare/lrpcrypto.c b/client/src/mifare/lrpcrypto.c
index e274b660b..9b1d0e0df 100644
--- a/client/src/mifare/lrpcrypto.c
+++ b/client/src/mifare/lrpcrypto.c
@@ -265,3 +265,13 @@ void LRPCMAC(LRPContext *ctx, uint8_t *data, size_t datalen, uint8_t *cmac) {
 
     LRPEvalLRP(ctx, y, CRYPTO_AES128_KEY_SIZE * 2, true, cmac);
 }
+
+void LRPCMAC8(LRPContext *ctx, uint8_t *data, size_t datalen, uint8_t *cmac) {
+    uint8_t cmac_tmp[16] = {0};
+    memset(cmac, 0x00, 8);
+
+    LRPCMAC(ctx, data, datalen, cmac_tmp);
+
+    for (int i = 0; i < 8; i++)
+        cmac[i] = cmac_tmp[i * 2 + 1];
+}
diff --git a/client/src/mifare/lrpcrypto.h b/client/src/mifare/lrpcrypto.h
index cf1653865..d3834b6c6 100644
--- a/client/src/mifare/lrpcrypto.h
+++ b/client/src/mifare/lrpcrypto.h
@@ -56,5 +56,6 @@ void LRPEncode(LRPContext *ctx, uint8_t *data, size_t datalen, uint8_t *resp, si
 void LRPDecode(LRPContext *ctx, uint8_t *data, size_t datalen, uint8_t *resp, size_t *resplen);
 void LRPGenSubkeys(uint8_t *key, uint8_t *sk1, uint8_t *sk2);
 void LRPCMAC(LRPContext *ctx, uint8_t *data, size_t datalen, uint8_t *cmac);
+void LRPCMAC8(LRPContext *ctx, uint8_t *data, size_t datalen, uint8_t *cmac);
 
 #endif // __LRPCRYPTO_H