WiP: producing a verifiable image

Assuming we have the correct key to verify with...

Signed-off-by: Bjørn Mork <bjorn@mork.no>

2 files changed, 42 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index 8a7381f..7dcd9d5 100644
--- a/Makefile
+++ b/Makefile
@@ -1,12 +1,49 @@
 # SPDX-License-Identifier: GPL-2.0
 # Copyright(c) 2019 Bjørn Mork <bjorn@mork.no>
 
-FILES=version opt.local 
+FILES=version opt.local
+PRIKEY=PriKey.pem
+SIGNKEY=signkey.pem
 
-all: opt.squashfs
+all: fw.tar
 
 version: dcs8000lh-configure.py
 	sed -ne 's/"//g' -e 's/^VERSION *= *//p' dcs8000lh-configure.py >$@
 
 opt.squashfs: $(FILES)
 	mksquashfs $(FILES) $@ -all-root -comp xz
+
+aes.key:
+	openssl rand 16 > $@
+
+aes.key.rsa: aes.key $(PRIKEY)
+	openssl rsautl -encrypt -in aes.key -inkey $(PRIKEY) -out $@
+
+### FIXME:  This is verified using the pubkey in /etc/db/verify.key, which will fail
+sign.sha1.rsa: sign.sha1 $(SIGNKEY)
+	openssl rsautl -sign -inkey $(SIGNKEY) -out sign.sha1.rsa -in sign.sha1
+
+$(SIGNKEY):
+	openssl genrsa -out $(SIGNKEY)
+
+sign.sha1: update.bin.aes aes.key.rsa certificate.info update.sha1
+	cat $^ | openssl dgst -sha1 | cut -d' ' -f2 > $@
+
+fw.tar: certificate.info aes.key.rsa sign.sha1.rsa update.aes update.bin.aes
+	tar cvf $@ $^
+
+update.sha1: update.aes
+	 openssl dgst -sha1 $^ | cut -d' ' -f2 > $@
+
+update.aes: aes.key opt.squashfs
+	openssl aes-128-cbc -md md5 -kfile aes.key -nosalt -e -out $@ -in opt.squashfs
+
+update.bin.aes: aes.key update.bin
+	openssl aes-128-cbc -md md5 -kfile aes.key -nosalt -e -out $@ -in update.bin
+
+clean:
+	rm *.rsa *.aes opt.squashfs sign.sha1
+
+distclean: clean
+	rm aes.key
+
diff --git a/dcs8000lh-configure.py b/dcs8000lh-configure.py
index 8f223d1..fff7e9d 100755
--- a/dcs8000lh-configure.py
+++ b/dcs8000lh-configure.py
@@ -124,6 +124,7 @@ if __name__ == '__main__':
     parser.add_argument("--command", help="Run command on IPCam")
     parser.add_argument("--telnetd", help="Start telnet server on IPCam", action="store_true")
     parser.add_argument("--lighttpd", help="Start web server on IPCam", action="store_true")
+    parser.add_argument("--unsignedfw", help="Allow unsigned firmware", action="store_true")
     parser.add_argument("--attrs", help="Dump IPCam GATT characteristics", action="store_true")
     parser.add_argument("-V", "--version", action="version", version="%(prog)s " + VERSION)
     args = parser.parse_args()
@@ -147,6 +148,8 @@ if __name__ == '__main__':
         cam.run_command("pidof telnetd||telnetd")
     if args.lighttpd:
         cam.run_command("/etc/rc.d/init.d/extra_lighttpd.sh start")
+    if args.unsignedfw:
+        cam.run_command("tdb set SecureFW _TrustLevel_byte=0")
     if args.attrs:
        cam.dumpchars()