nfc - Android HCE does not support select MF command? -

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we developing app based on android hce. found hce uses aid-based mechanism route communication specific apps. means if want trigger app, first command must select name command.

this big limitation on transport domain. in transport, many pos won't send select name command first command. instead send select mf (00a40000023f00) command first command. hce can't work in case.

is there plan add default select feature? or have other solution support use case?

android uses aid-based routing mechanism dispatch communication in card emulation mode specific application (hce applications or se applets). nfc forum designed primary means support multiple independent card emulation applications on single nfc device.

aid-based routing requires first command select (by df name/aid) command:

00 a4 0400 <lc> <aid> [<le>]

this necessary in order distinguish between different applications. otherwise, android not able dispatch communication right hce service.

however, prevents emulation of precedes successful application selection (such selecting master file using select (by file name, etc.) command). if allowed, android have no way know hce application responsible handling command. consequently, impossible host multiple hce applications require master file on 1 device. therefore, don't expect supported anytime soon.

on other mutli-application platforms same problem exists well. instance, typical java card smartcards not have master file. on these platforms, problem overcome allowing 1 default-selected application handles communication before first select (by df name/aid) command. 1 can speculate if such mechanism come in future android version...i not count on it.

if rooted devices option, may able use framework xposed adapt nfc system service dispatch communication default hce service.


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