Disclaimer
ALL CONTENT, WHETHER EXPRESS OR IMPLIED, ARE
OPEN INFORMATION. AUTHOR IN THE LEGAL IS
IRRESPONSIBLE FOR YOU.
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‧ Ba a maker, you can
‧ Learn more what you need
‧ Enjoy more what you like
‧ Understand more what you used
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‧ I want to design a popular WiFi AP
‧ Everyone want to access
‧ Everyone like to access
‧ Also, I’m happy everyone access my Wifi AP
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I want access WiFi
Your Wifi AP
Expose Your Device - hostapd
Assign A IP address - dnsmasq
Access WLAN - iptable
‧ hostapd
‧ A userspace daemon for wireless AP
‧ dnsmasq
‧ Lightweight DNS / DHCP server
‧ iptable
‧ Redirect WiFi packet into WLAN
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‧ If possible
‧ Everyone on the World is my custom⋯
‧ But only the 100m at most, limit by
‧ frequency band
‧ radio power
‧ ⋯ etc
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‧ If possible
‧ Everyone on the World is my custom⋯
‧ But only the 100m at most, limit by
‧ frequency band
‧ radio power
‧ ⋯ etc
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‧ In real scenario
‧ School, the total scope is larger than 100m
‧ You DO NOT want to repeat login.
‧ Did you realize that you switch to other AP
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‧ But the real flow are
1. Client send probe request (with SSID)
2. Server response
3. Client authentication
4. Server check and pass the authentication
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‧ But the real flow are
1. Client send probe request (with SSID)
2. Server response
3. Client authentication
4. Server check and pass the authentication
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‧ Every packets through router
‧ From, To and Data
‧ Name, address, and everything you talk on the
network.
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