You should know that Android 4.2.2 (or just before) introduced RSA key checking for adb access. – The device asks now if you want to allow access.
To avoid asking every time, the computer presents an RSA key, which can be permanently accepted.
The dialog on the phone shows the RSA key fingerprint. – On Linux, the public/secret key pair is here: ~/.android/adbkey(.pub).
How can I show the fingerprint of that key file? (I’m looking for a command line to do that on the Linux system.)
This line will do it (found here):
awk '{print $1}' < ~/.android/adbkey.pub | openssl base64 -A -d -a | openssl md5 -c
awk '{print $1}' < ~/.android/adbkey.pub | base64 --decode | md5sum works as well
Commented
Feb 23, 2019 at 8:02
adb pubkey ~/.android/adbkey | awk '{print $1}' \ | openssl base64 -A -a -d | openssl md5 -c | tr a-z A-Z to get the MD5 fingerprint. Source: joachimschuster.de/posts/debug-on-device-rsa-fingerprint
Run:
echo {public key} | base64 --decode | md5sum
On Android 5 and above, the hash function used was changed to sha256. If your hardware is such, your could try:
awk '{print $1}' < ~/.android/adbkey.pub | openssl base64 -A -d -a | openssl sha256 -c | awk '{print $2}'|tr '[:lower:]' '[:upper:]'
