WebAPI/WebNFC

Introduction

Current Status (As to Firefox OS v2.2)

• Gecko b2g-nfc meta bug, bug 860906
• Gecko b2g-secure-element meta bug bug 1044428
• Gaia meta bug, bug 933640
• nfcd meta bug, bug 1044425
• Gonk
  • Use a native daemon nfcd which links to native NFC library. nfcd github
• Hardware
  • Using Nexus-4/Nexus-5, which uses Broadcom NFC chipset with libnfc-nci library.
  • Flame, NXP chipsets with libnfc-nci library.

Security Review (By Paul Theriault and Stephanie Ouillon)

• https://wiki.mozilla.org/Security/Reviews/B2G/WebNFC
• Security Review for WebNFC: bug 749325
• Security Review for NFC Payment: bug 948280
• Security Review for NFC privilege API: bug 1095417

Contributors

• Gecko Engineers: Arno Puder, Garner Lee, Siddartha Pothapragada, Yoshi Huang, Dimi Lee
• Early Contributors: Markus Neubrand, Philipp von Weitershausen

Roadmap

First iteration: NDEF (Firefox OS v1.3)

• meta bug, bug 959692 - (b2g-NFC-1.3) [meta] FxOS v1.3 NFC feature
• Technologies:
  • Focus on NDEF standard only for now
  • Others (e.g. proprietary MIFARE) to be investigated later.
• Capabilities:
  • Read/write NDEF records on tags
  • bug 933136 - [Gecko] NFC onpeerready, onpeerlost callbacks
• Implementation:
  • See bug 674741
  • NDEF-only API is available on MozNFCTag object.
  • Discovered NDEF tags are automatically parsed and dispatched to content in the "nfc-manager-tech-discovered" system message.
  • navigator.mozNfc only available to a specific privileged content page (cf. WebTelephony, WebSMS).
  • For now, content is expected to do filtering and dispatching to handlers e.g. via WebActivity.
• Gonk
  • bug 906579 - B2G NFC: NFC Daemon for supporting libnfc-nci
• Hardware
  • Using Nexus-4, which uses Broadcom NFC chipset with libnfc-nci library.

Second iteration: Handover and other bug fixes (Firefox OS v1.4)

• meta bug : bug 949293 - (b2g-NFC-1.4) [meta] FxOS v1.4 NFC feature
• Capabilities:
  • bug 933093 NFC handover.
  • bug 916863 - [NFC] NFC support in emulator
  • NFC Manager API
    • bug 952217 - [B2G][NFC] Have a separate NFC application API and NFC Manager API
    • bug 959437 - Refactor NfcManager APIs and implementation details to support sendFile , notifyUserAcceptedP2P and other privileged Nfc operations

Third iteration: NFC Sharing feature, P2P, emulator support, test cases (Firefox OS v2.0)

• meta bug : bug 949293 - (b2g-NFC-2.0) [meta] FxOS v2.0 NFC feature
• NFC emulator: bug 973133
• More Gaia unit tests for NFC in apps/system/test/unit/

Fourth iteration: HCI transaction event (Firefox OS v2.1)

• bug 979767

Fifth iteration: Secure Element and NFC Privileged API (Firefox OS v2.2)

• bug 1044428 b2g-secure-element
  • bug 879861 - NFC Secure Element Support
• bug 1042851 - (b2g-nfc-privilege) (meta) [NFC] Make NFC APIs available to privileged webapps
  • Slide: http://bit.ly/1x7nWp5

Current API

Check DXR for latest NFC IDL

• MozNDEFRecord.webidl
• MozNFC.webidl
• MozNFCPeer.webidl
• MozNFCPeerEvent.webidl
• MozNFCTag.webidl
• MozNFCTagEvent.webidl

Usage of APIs

https://developer.mozilla.org/en-US/docs/Web/API/NFC_API

Application Permissions

NFC API has three permissions.

• nfc, which will be used by privileged applications.
• nfc-share, which will be used by ceritified(internal) applications.
• nfc-manager', which will be used by System app.

nfc permission could be used for general tag reading/writing, or sending NDEF to NFC Peer. nfc-share could be used to send large file (Blob) to another NFC peer. nfc-manager is used to control the RF state of NFC hardware.

Application Dispatch Order

1) Foreground App, if the callback ontagfound/onpeerfound is set.
2) If the foreground app doesn't register NFC callbacks or cannot process the event, the event will be redirected to System app, and System app will fire a nfc-ndef-discovered MozActivity.

NFC on B2G emulator

• See Kami's notes : https://bitbucket.org/kamituel/b2g-notepad/wiki/Using%20emulator

NFC Resources

Reference

• Introduction to NFC: http://www.adafruit.com/datasheets/Introduction_to_NFC_v1_0_en.pdf
• NDEF specification: NFCForum-TS-NDEF_1.0.pdf
• Understand NDEF messages : http://developer.nokia.com/Community/Wiki/Inside_NFC:_Understanding_NDEF_message
• NFC forum specifications: http://members.nfc-forum.org/specs/
• Handover specification: NFCForum-TS-ConnectionHandover_1_2.pdf

Similar APIs

• W3C NFC API: http://w3c.github.io/nfc/proposals/common/nfc.html
• Tizen NFC API: https://developer.tizen.org/dev-guide/2.2.0/org.tizen.web.device.apireference/tizen/nfc.html
• Android NFC API: http://developer.android.com/reference/android/nfc/package-summary.html