libcamera: Add IPA module signing infrastructure

Add infrastructure to generate an RSA private key and sign IPA modules.
The signatures are stored in separate files with a .sign suffix.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>

src/ipa/gen-ipa-priv-key.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2020, Google Inc.
+#
+# Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+#
+# gen-ipa-priv-key.sh - Generate an RSA private key to sign IPA modules
+
+key="$1"
+
+openssl genpkey -algorithm RSA -out "${key}" -pkeyopt rsa_keygen_bits:2048

src/ipa/ipa-sign.sh

@@ -0,0 +1,13 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2020, Google Inc.
+#
+# Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+#
+# ipa-sign.sh - Generate a signature for an IPA module
+
+key="$1"
+input="$2"
+output="$3"
+
+openssl dgst -sha256 -sign "${key}" -out "${output}" "${input}"

src/ipa/meson.build

@@ -10,6 +10,8 @@ config_h.set('IPA_MODULE_DIR',
 
 subdir('libipa')
 
+ipa_sign = find_program('ipa-sign.sh')
+
 ipas = ['rkisp1', 'vimc']
 
 foreach pipeline : get_option('pipelines')

src/ipa/rkisp1/meson.build

@@ -1,8 +1,17 @@
-rkisp1_ipa = shared_module('ipa_rkisp1',
-                           'rkisp1.cpp',
-                           name_prefix : '',
-                           include_directories : [ipa_includes, libipa_includes],
-                           dependencies : libcamera_dep,
-                           link_with : libipa,
-                           install : true,
-                           install_dir : ipa_install_dir)
+ipa_name = 'ipa_rkisp1'
+
+mod = shared_module(ipa_name,
+                    'rkisp1.cpp',
+                    name_prefix : '',
+                    include_directories : [ipa_includes, libipa_includes],
+                    dependencies : libcamera_dep,
+                    link_with : libipa,
+                    install : true,
+                    install_dir : ipa_install_dir)
+
+custom_target(ipa_name + '.so.sign',
+              input : mod,
+              output : ipa_name + '.so.sign',
+              command : [ ipa_sign, ipa_priv_key, '@INPUT@', '@OUTPUT@' ],
+              install : true,
+              install_dir : ipa_install_dir)

src/ipa/vimc/meson.build

@@ -1,4 +1,7 @@
-ipa = shared_module('ipa_vimc', 'vimc.cpp',
+ipa_name = 'ipa_vimc'
+
+mod = shared_module(ipa_name,
+                    'vimc.cpp',
                     name_prefix : '',
                     include_directories : [ipa_includes, libipa_includes],
                     dependencies : libcamera_dep,
@@ -6,3 +9,10 @@ ipa = shared_module('ipa_vimc', 'vimc.cpp',
                     install : true,
                     install_dir : ipa_install_dir,
                     cpp_args : '-DLICENSE="LGPL-2.1-or-later"')
+
+custom_target(ipa_name + '.so.sign',
+              input : mod,
+              output : ipa_name + '.so.sign',
+              command : [ ipa_sign, ipa_priv_key, '@INPUT@', '@OUTPUT@' ],
+              install : true,
+              install_dir : ipa_install_dir)

src/meson.build

@@ -2,6 +2,11 @@ if get_option('android')
     subdir('android')
 endif
 
+ipa_gen_priv_key = find_program('ipa/gen-ipa-priv-key.sh')
+ipa_priv_key = custom_target('ipa-priv-key',
+                             output : [ 'ipa-priv-key.pem' ],
+                             command : [ ipa_gen_priv_key, '@OUTPUT@' ])
+
 subdir('libcamera')
 subdir('ipa')
 subdir('cam')