diff --git a/Makefile b/Makefile
index 7655ccf..04b4619 100644
--- a/Makefile
+++ b/Makefile
@@ -18,7 +18,7 @@ obj = $(src:.c=.o) uECC.o
 LDFLAGS = -Wl,--gc-sections ./tinycbor/lib/libtinycbor.a
 CFLAGS = -O2 -fdata-sections -ffunction-sections 
 
-INCLUDES = -I./tinycbor/src -I./crypto/sha256 -I./crypto/micro-ecc/ -Icrypto/tiny-AES-c/ -I./fido2/ -I./pc
+INCLUDES = -I./tinycbor/src -I./crypto/sha256 -I./crypto/micro-ecc/ -Icrypto/tiny-AES-c/ -I./fido2/ -I./pc -I./fido2/extensions
 
 CFLAGS += $(INCLUDES)
 
diff --git a/targets/efm32/.cproject b/targets/efm32/.cproject
index 4f6fe54..844809e 100644
--- a/targets/efm32/.cproject
+++ b/targets/efm32/.cproject
@@ -28,7 +28,7 @@
 				<configuration artifactName="${ProjName}" buildArtefactType="org.eclipse.cdt.build.core.buildArtefactType.exe" buildProperties="org.eclipse.cdt.build.core.buildArtefactType=org.eclipse.cdt.build.core.buildArtefactType.exe" description="" id="com.silabs.ss.tool.ide.arm.toolchain.gnu.cdt.debug#com.silabs.ss.tool.ide.arm.toolchain.gnu.cdt:7.2.1.20170904" name="GNU ARM v7.2.1 - Debug" parent="com.silabs.ide.si32.gcc.cdt.managedbuild.config.gnu.exe">
 					<folderInfo id="com.silabs.ss.tool.ide.arm.toolchain.gnu.cdt.debug#com.silabs.ss.tool.ide.arm.toolchain.gnu.cdt:7.2.1.20170904." name="/" resourcePath="">
 						<toolChain id="com.silabs.ide.si32.gcc.cdt.managedbuild.toolchain.exe.1911691633" name="Si32 GNU ARM" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.toolchain.exe">
-							<option id="com.silabs.ide.si32.gcc.cdt.managedbuild.toolchain.debug.level.50213284" name="Debug Level" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.toolchain.debug.level" value="com.silabs.ide.si32.gcc.cdt.managedbuild.toolchain.debug.level.default" valueType="enumerated"/>
+							<option id="com.silabs.ide.si32.gcc.cdt.managedbuild.toolchain.debug.level.50213284" name="Debug Level" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.toolchain.debug.level" value="com.silabs.ide.si32.gcc.cdt.managedbuild.toolchain.debug.level.none" valueType="enumerated"/>
 							<option id="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.usescript.567506607" name="Use custom linker script" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.usescript" value="false" valueType="boolean"/>
 							<option id="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.script.583769327" name="Linker Script:" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.script" value="C:\Users\conor\Desktop\u2f-one\efm32\boot\EFM32.ld" valueType="string"/>
 							<option id="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.overrideflash.89245522" name="Override default flash options" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.overrideflash" value="true" valueType="boolean"/>
@@ -59,11 +59,6 @@
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/platform/emdrv/config/inc&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${workspace_loc:/${ProjName}/Drivers}&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${workspace_loc:/${ProjName}/EFM32/inc}&quot;"/>
-									<listOptionValue builtIn="false" value="C:/Users/conor/Desktop/u2f-one/crypto/sha256"/>
-									<listOptionValue builtIn="false" value="C:/Users/conor/Desktop/u2f-one/crypto/micro-ecc"/>
-									<listOptionValue builtIn="false" value="C:/Users/conor/Desktop/u2f-one/crypto/tiny-AES-c"/>
-									<listOptionValue builtIn="false" value="C:/Users/conor/Desktop/u2f-one/fido2"/>
-									<listOptionValue builtIn="false" value="C:/Users/conor/Desktop/u2f-one/tinycbor/src"/>
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/platform/emdrv/dmadrv/inc&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/platform/emdrv/common/inc&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/platform/emdrv/config&quot;"/>
@@ -71,10 +66,16 @@
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/platform/CMSIS/Include&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/platform/emlib/inc&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/util/third_party/mbedtls/configs&quot;"/>
-									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/util/third_party/mbedtls/include&quot;"/>
-									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/util/third_party/mbedtls/include/mbedtls&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/util/third_party/mbedtls/sl_crypto/include&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/util/third_party/mbedtls/sl_crypto/src&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${workspace_loc:/${ProjName}}/../../crypto/micro-ecc&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${workspace_loc:/${ProjName}}/../../crypto/tiny-AES-c&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${workspace_loc:/${ProjName}}/../../fido2&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${workspace_loc:/${ProjName}}/../../fido2/extensions&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${workspace_loc:/${ProjName}}/../../tinycbor/src&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${workspace_loc:/${ProjName}}/../../crypto/sha256&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/util/third_party/mbedtls/include/mbedtls&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${StudioSdkPath}/util/third_party/mbedtls/include&quot;"/>
 								</option>
 								<option id="gnu.c.compiler.option.include.files.824541460" name="Include files (-include)" superClass="gnu.c.compiler.option.include.files"/>
 								<inputType id="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.compiler.input.492241787" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.compiler.input"/>
@@ -117,7 +118,7 @@
 								<option id="gnu.c.link.option.paths.921756731" name="Library search path (-L)" superClass="gnu.c.link.option.paths" valueType="libPaths">
 									<listOptionValue builtIn="false" value="C:/Users/conor/Desktop/u2f-one/tinycbor/lib/"/>
 								</option>
-								<option id="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.category.ordering.selection.172160776" name="Linker input ordering" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.category.ordering.selection" value="./src/InitDevice.o;./src/device.o;./src/main.o;./src/printing.o;./src/retargetio.o;./fido2/ctap.o;./fido2/ctap_parse.o;./fido2/ctaphid.o;./fido2/log.o;./fido2/main.o;./fido2/stubs.o;./fido2/test_power.o;./fido2/u2f.o;./fido2/util.o;./emlib/em_assert.o;./emlib/em_cmu.o;./emlib/em_cryotimer.o;./emlib/em_emu.o;./emlib/em_gpio.o;./emlib/em_system.o;./emlib/em_usart.o;./crypto/tiny-AES-c/aes.o;./crypto/sha256/sha256.o;./crypto/micro-ecc/uECC.o;-ltinycbor;./src/crypto.o;./src/nfc.o;./sl_crypto/aesdrv_authencr_aes.o;./sl_crypto/aesdrv_authencr_crypto.o;./sl_crypto/aesdrv_blockcipher_aes.o;./sl_crypto/aesdrv_blockcipher_crypto.o;./sl_crypto/aesdrv_common.o;./sl_crypto/aesdrv_common_aes.o;./sl_crypto/aesdrv_common_crypto.o;./sl_crypto/sl_aes.o;./sl_crypto/sl_ecp.o;./sl_crypto/sl_entropy.o;./sl_crypto/sl_sha1.o;./sl_crypto/sl_sha256.o;./sl_crypto/sl_timing.o;./sl_crypto/slcl_aes.o;./sl_crypto/slcl_ccm.o;./sl_crypto/slcl_cmac.o;./sl_crypto/slcl_device.o;./sl_crypto/slcl_device_aes.o;./sl_crypto/slcl_device_crypto.o;./sl_crypto/slcl_ecp.o;./sl_crypto/slcl_sha1.o;./sl_crypto/slcl_sha256.o;./sl_crypto/sldp.o;./sl_crypto/slpal_freertos.o;./sl_crypto/slpal_ucos3.o;./sl_crypto/trng.o;./mbedtls/aes.o;./mbedtls/aesni.o;./mbedtls/arc4.o;./mbedtls/asn1parse.o;./mbedtls/asn1write.o;./mbedtls/base64.o;./mbedtls/bignum.o;./mbedtls/blowfish.o;./mbedtls/camellia.o;./mbedtls/ccm.o;./mbedtls/certs.o;./mbedtls/cipher.o;./mbedtls/cipher_wrap.o;./mbedtls/ctr_drbg.o;./mbedtls/debug.o;./mbedtls/des.o;./mbedtls/dhm.o;./mbedtls/ecdh.o;./mbedtls/ecdsa.o;./mbedtls/ecjpake.o;./mbedtls/ecp.o;./mbedtls/ecp_curves.o;./mbedtls/entropy.o;./mbedtls/entropy_poll.o;./mbedtls/error.o;./mbedtls/gcm.o;./mbedtls/havege.o;./mbedtls/hmac_drbg.o;./mbedtls/md.o;./mbedtls/md2.o;./mbedtls/md4.o;./mbedtls/md5.o;./mbedtls/md_wrap.o;./mbedtls/memory_buffer_alloc.o;./mbedtls/net.o;./mbedtls/oid.o;./mbedtls/padlock.o;./mbedtls/pem.o;./mbedtls/pk.o;./mbedtls/pk_wrap.o;./mbedtls/pkcs11.o;./mbedtls/pkcs12.o;./mbedtls/pkcs5.o;./mbedtls/pkparse.o;./mbedtls/pkwrite.o;./mbedtls/platform.o;./mbedtls/ripemd160.o;./mbedtls/rsa.o;./mbedtls/sha1.o;./mbedtls/sha256.o;./mbedtls/sha512.o;./mbedtls/ssl_cache.o;./mbedtls/ssl_ciphersuites.o;./mbedtls/ssl_cli.o;./mbedtls/ssl_cookie.o;./mbedtls/ssl_srv.o;./mbedtls/ssl_ticket.o;./mbedtls/ssl_tls.o;./mbedtls/threading.o;./mbedtls/timing.o;./mbedtls/version.o;./mbedtls/version_features.o;./mbedtls/x509.o;./mbedtls/x509_create.o;./mbedtls/x509_crl.o;./mbedtls/x509_crt.o;./mbedtls/x509_csr.o;./mbedtls/x509write_crt.o;./mbedtls/x509write_csr.o;./mbedtls/xtea.o;./fido2/wallet.o;./emlib/em_adc.o;./emlib/em_crypto.o;./emlib/em_msc.o;./emlib/em_timer.o;./CMSIS/EFM32JG1B/startup_efm32jg1b.o;./CMSIS/EFM32JG1B/system_efm32jg1b.o" valueType="string"/>
+								<option id="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.category.ordering.selection.172160776" name="Linker input ordering" superClass="com.silabs.ide.si32.gcc.cdt.managedbuild.tool.gnu.c.linker.category.ordering.selection" value="./src/InitDevice.o;./src/device.o;./src/main.o;./src/printing.o;./src/retargetio.o;./fido2/ctap.o;./fido2/ctap_parse.o;./fido2/ctaphid.o;./fido2/log.o;./fido2/main.o;./fido2/stubs.o;./fido2/test_power.o;./fido2/u2f.o;./fido2/util.o;./emlib/em_assert.o;./emlib/em_cmu.o;./emlib/em_cryotimer.o;./emlib/em_emu.o;./emlib/em_gpio.o;./emlib/em_system.o;./emlib/em_usart.o;./crypto/tiny-AES-c/aes.o;./crypto/sha256/sha256.o;./crypto/micro-ecc/uECC.o;-ltinycbor;./src/crypto.o;./src/nfc.o;./sl_crypto/aesdrv_authencr_aes.o;./sl_crypto/aesdrv_authencr_crypto.o;./sl_crypto/aesdrv_blockcipher_aes.o;./sl_crypto/aesdrv_blockcipher_crypto.o;./sl_crypto/aesdrv_common.o;./sl_crypto/aesdrv_common_aes.o;./sl_crypto/aesdrv_common_crypto.o;./sl_crypto/sl_aes.o;./sl_crypto/sl_ecp.o;./sl_crypto/sl_entropy.o;./sl_crypto/sl_sha1.o;./sl_crypto/sl_sha256.o;./sl_crypto/sl_timing.o;./sl_crypto/slcl_aes.o;./sl_crypto/slcl_ccm.o;./sl_crypto/slcl_cmac.o;./sl_crypto/slcl_device.o;./sl_crypto/slcl_device_aes.o;./sl_crypto/slcl_device_crypto.o;./sl_crypto/slcl_ecp.o;./sl_crypto/slcl_sha1.o;./sl_crypto/slcl_sha256.o;./sl_crypto/sldp.o;./sl_crypto/slpal_freertos.o;./sl_crypto/slpal_ucos3.o;./sl_crypto/trng.o;./mbedtls/aes.o;./mbedtls/aesni.o;./mbedtls/arc4.o;./mbedtls/asn1parse.o;./mbedtls/asn1write.o;./mbedtls/base64.o;./mbedtls/bignum.o;./mbedtls/blowfish.o;./mbedtls/camellia.o;./mbedtls/ccm.o;./mbedtls/certs.o;./mbedtls/cipher.o;./mbedtls/cipher_wrap.o;./mbedtls/ctr_drbg.o;./mbedtls/debug.o;./mbedtls/des.o;./mbedtls/dhm.o;./mbedtls/ecdh.o;./mbedtls/ecdsa.o;./mbedtls/ecjpake.o;./mbedtls/ecp.o;./mbedtls/ecp_curves.o;./mbedtls/entropy.o;./mbedtls/entropy_poll.o;./mbedtls/error.o;./mbedtls/gcm.o;./mbedtls/havege.o;./mbedtls/hmac_drbg.o;./mbedtls/md.o;./mbedtls/md2.o;./mbedtls/md4.o;./mbedtls/md5.o;./mbedtls/md_wrap.o;./mbedtls/memory_buffer_alloc.o;./mbedtls/net.o;./mbedtls/oid.o;./mbedtls/padlock.o;./mbedtls/pem.o;./mbedtls/pk.o;./mbedtls/pk_wrap.o;./mbedtls/pkcs11.o;./mbedtls/pkcs12.o;./mbedtls/pkcs5.o;./mbedtls/pkparse.o;./mbedtls/pkwrite.o;./mbedtls/platform.o;./mbedtls/ripemd160.o;./mbedtls/rsa.o;./mbedtls/sha1.o;./mbedtls/sha256.o;./mbedtls/sha512.o;./mbedtls/ssl_cache.o;./mbedtls/ssl_ciphersuites.o;./mbedtls/ssl_cli.o;./mbedtls/ssl_cookie.o;./mbedtls/ssl_srv.o;./mbedtls/ssl_ticket.o;./mbedtls/ssl_tls.o;./mbedtls/threading.o;./mbedtls/timing.o;./mbedtls/version.o;./mbedtls/version_features.o;./mbedtls/xtea.o;./fido2/wallet.o;./emlib/em_adc.o;./emlib/em_crypto.o;./emlib/em_msc.o;./emlib/em_timer.o;./CMSIS/EFM32JG1B/startup_efm32jg1b.o;./CMSIS/EFM32JG1B/system_efm32jg1b.o" valueType="string"/>
 								<inputType id="cdt.managedbuild.tool.gnu.c.linker.input.1977486948" superClass="cdt.managedbuild.tool.gnu.c.linker.input">
 									<additionalInput kind="additionalinputdependency" paths="$(USER_OBJS)"/>
 									<additionalInput kind="additionalinput" paths="$(LIBS)"/>
diff --git a/targets/efm32/.project b/targets/efm32/.project
index 8fc5500..be49028 100644
--- a/targets/efm32/.project
+++ b/targets/efm32/.project
@@ -28,12 +28,12 @@
 		<link>
 			<name>crypto</name>
 			<type>2</type>
-			<location>C:/Users/conor/Desktop/u2f-one/crypto/</location>
+			<locationURI>$%7BPARENT-2-PROJECT_LOC%7D/crypto</locationURI>
 		</link>
 		<link>
 			<name>fido2</name>
 			<type>2</type>
-			<location>C:/Users/conor/Desktop/u2f-one/fido2/</location>
+			<locationURI>$%7BPARENT-2-PROJECT_LOC%7D/fido2</locationURI>
 		</link>
 		<link>
 			<name>CMSIS/EFM32JG1B/startup_gcc_efm32jg1b.s</name>
diff --git a/targets/efm32/inc/app.h b/targets/efm32/inc/app.h
index d9b4b40..63ee63f 100644
--- a/targets/efm32/inc/app.h
+++ b/targets/efm32/inc/app.h
@@ -14,7 +14,9 @@
 
 //#define USING_DEV_BOARD
 
-//#define BRIDGE_TO_WALLET
+//#define ENABLE_U2F_EXTENSIONS
+
+#define ENABLE_U2F
 
 //#define DISABLE_CTAPHID_PING
 //#define DISABLE_CTAPHID_WINK
diff --git a/targets/efm32boot/.cproject b/targets/efm32boot/.cproject
index 626f875..b87fa56 100644
--- a/targets/efm32boot/.cproject
+++ b/targets/efm32boot/.cproject
@@ -49,6 +49,7 @@
 									<listOptionValue builtIn="false" value="&quot;${ProjDirPath}/inc&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${ProjDirPath}/../efm32/inc&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${ProjDirPath}/../../fido2&quot;"/>
+									<listOptionValue builtIn="false" value="&quot;${ProjDirPath}/../../fido2/extensions&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${ProjDirPath}/../../tinycbor/src&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${ProjDirPath}/../../crypto/sha256&quot;"/>
 									<listOptionValue builtIn="false" value="&quot;${ProjDirPath}/../../crypto/micro-ecc&quot;"/>