For Samsung FRP, the pack reroutes the Google account verification server to a local host (127.0.0.1). It sends a "Success" packet even though no real authentication occurred, tricking the phone into opening the home screen.
Huawei phones with Kirin chips are usually locked down. However, Gsm Pack V3.0 focuses on Huawei devices running MediaTek or older Qualcomm chips (Huawei Y series). It includes the HCU Client crack for reading bootloader codes. Gsm Pack V3.0 Modsapps99