2 files changed, 191 insertions, 1 deletions

diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
index 08dce14f2dc8..2a4d1a176526 100644
--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -14,7 +14,8 @@
 # 3)  create one <module>.mod.c file pr. module
 # 4)  create one Module.symvers file with CRC for all exported symbols
 # 5) compile all <module>.mod.c files
-# 6) final link of the module to a <module.ko> file
+# 6) final link of the module to a <module.ko> (or <module.unsigned>) file
+# 7) signs the modules to a <module.ko> file
 
 # Step 3 is used to place certain information in the module's ELF
 # section, including information such as:
@@ -32,6 +33,8 @@
 # Step 4 is solely used to allow module versioning in external modules,
 # where the CRC of each module is retrieved from the Module.symvers file.
 
+# Step 7 is dependent on CONFIG_MODULE_SIG being enabled.
+
 # KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined
 # symbols in the final module linking stage
 # KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
@@ -116,6 +119,7 @@ $(modules:.ko=.mod.o): %.mod.o: %.mod.c FORCE
 targets += $(modules:.ko=.mod.o)
 
 # Step 6), final link of the modules
+ifneq ($(CONFIG_MODULE_SIG),y)
 quiet_cmd_ld_ko_o = LD [M]  $@
       cmd_ld_ko_o = $(LD) -r $(LDFLAGS)                                 \
                              $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \
@@ -125,7 +129,78 @@ $(modules): %.ko :%.o %.mod.o FORCE
         $(call if_changed,ld_ko_o)
 
 targets += $(modules)
+else
+quiet_cmd_ld_ko_unsigned_o = LD [M]  $@
+      cmd_ld_ko_unsigned_o =                                            \
+                $(LD) -r $(LDFLAGS)                                     \
+                         $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE)     \
+                         -o $@ $(filter-out FORCE,$^)                   \
+                $(if $(AFTER_LINK),; $(AFTER_LINK))
+
+$(modules:.ko=.ko.unsigned): %.ko.unsigned :%.o %.mod.o FORCE
+        $(call if_changed,ld_ko_unsigned_o)
+
+targets += $(modules:.ko=.ko.unsigned)
+
+# Step 7), sign the modules
+MODSECKEY = ./signing_key.priv
+MODPUBKEY = ./signing_key.x509
+
+ifeq ($(wildcard $(MODSECKEY))+$(wildcard $(MODPUBKEY)),$(MODSECKEY)+$(MODPUBKEY))
+ifeq ($(KBUILD_SRC),)
+        # no O= is being used
+        SCRIPTS_DIR := scripts
+else
+        SCRIPTS_DIR := $(KBUILD_SRC)/scripts
+endif
+SIGN_MODULES := 1
+else
+SIGN_MODULES := 0
+endif
+
+# only sign if it's an in-tree module
+ifneq ($(KBUILD_EXTMOD),)
+SIGN_MODULES := 0
+endif
 
+# We strip the module as best we can - note that using both strip and eu-strip
+# results in a smaller module than using either alone.
+EU_STRIP = $(shell which eu-strip || echo true)
+
+quiet_cmd_sign_ko_stripped_ko_unsigned = STRIP [M] $@
+      cmd_sign_ko_stripped_ko_unsigned = \
+                cp $< $@ && \
+                strip -x -g $@ && \
+                $(EU_STRIP) $@
+
+ifeq ($(SIGN_MODULES),1)
+
+quiet_cmd_genkeyid = GENKEYID $@
+      cmd_genkeyid = \
+                perl $(SCRIPTS_DIR)/x509keyid $< $<.signer $<.keyid
+
+%.signer %.keyid: %
+        $(call if_changed,genkeyid)
+
+KEYRING_DEP := $(MODSECKEY) $(MODPUBKEY) $(MODPUBKEY).signer $(MODPUBKEY).keyid
+quiet_cmd_sign_ko_ko_stripped = SIGN [M] $@
+      cmd_sign_ko_ko_stripped = \
+                sh $(SCRIPTS_DIR)/sign-file $(MODSECKEY) $(MODPUBKEY) $< $@
+else
+KEYRING_DEP :=
+quiet_cmd_sign_ko_ko_unsigned = NO SIGN [M] $@
+      cmd_sign_ko_ko_unsigned = \
+                cp $< $@
+endif
+
+$(modules): %.ko :%.ko.stripped $(KEYRING_DEP) FORCE
+        $(call if_changed,sign_ko_ko_stripped)
+
+$(patsubst %.ko,%.ko.stripped,$(modules)): %.ko.stripped :%.ko.unsigned FORCE
+        $(call if_changed,sign_ko_stripped_ko_unsigned)
+
+targets += $(modules)
+endif
 
 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 # ---------------------------------------------------------------------------
diff --git a/scripts/sign-file b/scripts/sign-file
new file mode 100644
index 000000000000..e58e34e50ac5
--- /dev/null
+++ b/scripts/sign-file
@@ -0,0 +1,115 @@
+#!/bin/sh
+#
+# Sign a module file using the given key.
+#
+# Format: sign-file <key> <x509> <src-file> <dst-file>
+#
+
+scripts=`dirname $0`
+
+CONFIG_MODULE_SIG_SHA512=y
+if [ -r .config ]
+then
+    . ./.config
+fi
+
+key="$1"
+x509="$2"
+src="$3"
+dst="$4"
+
+if [ ! -r "$key" ]
+then
+    echo "Can't read private key" >&2
+    exit 2
+fi
+
+if [ ! -r "$x509" ]
+then
+    echo "Can't read X.509 certificate" >&2
+    exit 2
+fi
+if [ ! -r "$x509.signer" ]
+then
+    echo "Can't read Signer name" >&2
+    exit 2;
+fi
+if [ ! -r "$x509.keyid" ]
+then
+    echo "Can't read Key identifier" >&2
+    exit 2;
+fi
+
+#
+# Signature parameters
+#
+algo=1          # Public-key crypto algorithm: RSA
+hash=           # Digest algorithm
+id_type=1       # Identifier type: X.509
+
+#
+# Digest the data
+#
+dgst=
+if [ "$CONFIG_MODULE_SIG_SHA1" = "y" ]
+then
+    prologue="0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2B, 0x0E, 0x03, 0x02, 0x1A, 0x05, 0x00, 0x04, 0x14"
+    dgst=-sha1
+    hash=2
+elif [ "$CONFIG_MODULE_SIG_SHA224" = "y" ]
+then
+    prologue="0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, 0x05, 0x00, 0x04, 0x1C"
+    dgst=-sha224
+    hash=7
+elif [ "$CONFIG_MODULE_SIG_SHA256" = "y" ]
+then
+    prologue="0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20"
+    dgst=-sha256
+    hash=4
+elif [ "$CONFIG_MODULE_SIG_SHA384" = "y" ]
+then
+    prologue="0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00, 0x04, 0x30"
+    dgst=-sha384
+    hash=5
+elif [ "$CONFIG_MODULE_SIG_SHA512" = "y" ]
+then
+    prologue="0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40"
+    dgst=-sha512
+    hash=6
+else
+    echo "$0: Can't determine hash algorithm" >&2
+    exit 2
+fi
+
+(
+perl -e "binmode STDOUT; print pack(\"C*\", $prologue)" || exit $?
+openssl dgst $dgst -binary $src || exit $?
+) >$src.dig || exit $?
+
+#
+# Generate the binary signature, which will be just the integer that comprises
+# the signature with no metadata attached.
+#
+openssl rsautl -sign -inkey $key -keyform PEM -in $src.dig -out $src.sig || exit $?
+signerlen=`stat -c %s $x509.signer`
+keyidlen=`stat -c %s $x509.keyid`
+siglen=`stat -c %s $src.sig`
+
+#
+# Build the signed binary
+#
+(
+    cat $src || exit $?
+    echo '~Module signature appended~' || exit $?
+    cat $x509.signer $x509.keyid || exit $?
+
+    # Preface each signature integer with a 2-byte BE length
+    perl -e "binmode STDOUT; print pack(\"n\", $siglen)" || exit $?
+    cat $src.sig || exit $?
+
+    # Generate the information block
+    perl -e "binmode STDOUT; print pack(\"CCCCCxxxN\", $algo, $hash, $id_type, $signerlen, $keyidlen, $siglen + 2)" || exit $?
+) >$dst~ || exit $?
+
+# Permit in-place signing
+mv $dst~ $dst || exit $?