Do not use format stirngs for compatibility

The format strings we use are only supported on Python 3.6 and
above. With openwifi we likely need to support an older Python
version.

This patch may be reverted in the future once support for older
Python versions is no longer needed.

krackattack/krack-ft-test.py

@@ -156,7 +156,7 @@ if __name__ == "__main__":
 	# Check if we're using the expected scapy version
 	expected_ver = get_expected_scapy_ver()
 	if expected_ver!= None and scapy.VERSION != expected_ver:
-		log(WARNING, f"You are using scapy version {scapy.VERSION} instead of the expected {expected_ver}")
+		log(WARNING, "You are using scapy version {} instead of the expected {}".format(scapy.VERSION, expected_ver))
 		log(WARNING, "Are you executing the script from inside the correct python virtual environment?")
 
 	# TODO: Verify that we only accept CCMP?

krackattack/krack-test-client.py

@@ -314,7 +314,7 @@ class KRAckAttackClient():
 		if plaintext == None:
 			return
 		if not SNAP in plaintext:
-			log(WARNING, f"No SNAP layer in decrypted packet {plaintext}")
+			log(WARNING, "No SNAP layer in decrypted packet {}".format(plaintext))
 			return None
 
 		# Now process the packet as if it were a valid (non-replayed) one
@@ -342,10 +342,10 @@ class KRAckAttackClient():
 					#   it will always think a device reinstalls the group key, because the ath9k_htc
 					#   will always use an incremented IV when though we reset the group key. We also
 					#   can't seem to detect this in userspace because the hardware may override the IV?
-					log(WARNING, f"Hardware decryption detected! Attemping to still detect IV reuse, but this is unreliable.")
-					log(ERROR, f"!!! Ideally you disable hardware decryption or use a different network card !!!")
-					log(WARNING, f"E.g., detecting all-zero key use may currently be unreliable, and with some network")
-					log(WARNING, f"      cards key reinstallations cannot be detected at all currently...")
+					log(WARNING, "Hardware decryption detected! Attemping to still detect IV reuse, but this is unreliable.")
+					log(ERROR, "!!! Ideally you disable hardware decryption or use a different network card !!!")
+					log(WARNING, "E.g., detecting all-zero key use may currently be unreliable, and with some network")
+					log(WARNING, "      cards key reinstallations cannot be detected at all currently...")
 					warned_hardware_decryption = True
 			else:
 				# Whether an IV is included may depend on the direction of the packet. For instance,
@@ -353,7 +353,7 @@ class KRAckAttackClient():
 				# but the IV *is* included in received frames.
 				log(ERROR, "Hardware decryption seems to be dropping the IV, meaning we cannot detect key reinstallations.")
 				log(ERROR, "Try to disable hardware decryption, use a different network card, or report this as a bug.")
-				log(WARNING, f"Frame causing the issue: {repr(p)} with raw data being {p}")
+				log(WARNING, "Frame causing the issue: {} with raw data being {}".format(repr(p), p))
 				quit(1)
 
 	def handle_mon_rx(self):
@@ -617,7 +617,7 @@ if __name__ == "__main__":
 	# Check if we're using the expected scapy version
 	expected_ver = get_expected_scapy_ver()
 	if expected_ver!= None and scapy.VERSION != expected_ver:
-		log(WARNING, f"You are using scapy version {scapy.VERSION} instead of the expected {expected_ver}")
+		log(WARNING, "You are using scapy version {} instead of the expected {}".format(scapy.VERSION, expected_ver))
 		log(WARNING, "Are you executing the script from inside the correct python virtual environment?")
 
 	options = TestOptions()