diff --git a/include/prereq-build.mk b/include/prereq-build.mk
index 59ea7ef9a7..b7ada69bb4 100644
--- a/include/prereq-build.mk
+++ b/include/prereq-build.mk
@@ -168,6 +168,10 @@ $(eval $(call RequireCommand,svn, \
 	Please install the subversion client. \
 ))
 
+$(eval $(call RequireCommand,openssl, \
+	Please install openssl. \
+))
+
 define Require/gnu-find
 	$(FIND) --version 2>/dev/null
 endef
diff --git a/package/Makefile b/package/Makefile
index 00ac773499..bac7001c4f 100644
--- a/package/Makefile
+++ b/package/Makefile
@@ -120,10 +120,35 @@ $(curdir)/install: $(TMP_DIR)/.build
 	$(if $(CONFIG_CLEAN_IPKG),rm -rf $(TARGET_DIR)/usr/lib/opkg)
 	$(call mklibs)
 
+PASSOPT=""
+PASSARG=""
+ifndef CONFIG_OPKGSMIME_PASSPHRASE
+  ifneq ($(call qstrip,$(CONFIG_OPKGSMIME_PASSFILE)),)
+    PASSOPT="-passin"
+    PASSARG="file:$(call qstrip,$(CONFIG_OPKGSMIME_PASSFILE))"
+  endif
+endif
+
 $(curdir)/index: FORCE
-	@(cd $(PACKAGE_DIR); $(SCRIPT_DIR)/ipkg-make-index.sh . 2>&1 > Packages && \
-		gzip -9c Packages > Packages.gz \
-	)
+ifeq ($(call qstrip,$(CONFIG_OPKGSMIME_KEY)),)
+	@echo Signing key has not been configured
+else
+ifeq ($(call qstrip,$(CONFIG_OPKGSMIME_CERT)),)
+	@echo Certificate has not been configured
+else
+	@echo Generating package index...
+	@(cd $(PACKAGE_DIR); \
+		$(SCRIPT_DIR)/ipkg-make-index.sh . 2>&1 > Packages && \
+		gzip -9c Packages > Packages.gz )
+	@echo Signing package index...
+	@(cd $(PACKAGE_DIR); \
+		openssl smime -binary -in Packages.gz \
+			-out Packages.sig -outform PEM -sign \
+			-signer $(CONFIG_OPKGSMIME_CERT) \
+			-inkey $(CONFIG_OPKGSMIME_KEY) \
+			$(PASSOPT) $(PASSARG) )
+endif
+endif
 
 $(curdir)/preconfig:
 
diff --git a/package/base-files/image-config.in b/package/base-files/image-config.in
index ac08c8da7c..a9eb78c4f9 100644
--- a/package/base-files/image-config.in
+++ b/package/base-files/image-config.in
@@ -183,3 +183,41 @@ menuconfig VERSIONOPT
 			 %d .. Distribution name or "openwrt", lowercase
 			 %T .. Target name
 			 %S .. Target/Subtarget name
+
+menuconfig SMIMEOPT
+	bool "Package signing options" if IMAGEOPT
+        default n
+	help
+		These options configure the signing key and certificate to
+		be used for signing and verifying packages.
+
+	config OPKGSMIME_CERT
+		string
+		prompt "Path to certificate (PEM certificate format)" if SMIMEOPT
+		help
+		  Path to the certificate to use for signature verification
+
+	config OPKGSMIME_KEY
+		string
+		prompt "Path to signing key (PEM private key format)" if SMIMEOPT
+		help
+		  Path to the key to use for signing packages
+
+	config OPKGSMIME_PASSPHRASE
+		bool
+		default y
+		prompt "Wait for a passphrase when signing packages?" if SMIMEOPT
+		help
+		  If this value is set, then the build will pause and request a passphrase
+                  from the command line when signing packages. This SHOULD NOT be used with
+                  automatic builds. If this value is not set, a file can be specified from
+                  which the passphrase will be read.
+
+	config OPKGSMIME_PASSFILE
+		string
+		prompt "Path to a file containing the passphrase" if SMIMEOPT
+                depends on !OPKGSMIME_PASSPHRASE
+		help
+		  Path to a file containing the passphrase for the signing key.
+                  If the signing key is not encrypted and does not require a passphrase,
+                  this option may be left blank.
diff --git a/package/system/opkg/Makefile b/package/system/opkg/Makefile
index eb3b10a776..3327a8e1ad 100644
--- a/package/system/opkg/Makefile
+++ b/package/system/opkg/Makefile
@@ -109,8 +109,12 @@ define Package/opkg/Default/install
 endef
 
 Package/opkg/install = $(call Package/opkg/Default/install,$(1),)
-Package/opkg-smime/install = $(call Package/opkg/Default/install,$(1),-smime)
 
+define Package/opkg-smime/install
+	$(call Package/opkg/Default/install,$(1),-smime)
+	$(INSTALL_DIR) $(1)/etc/ssl/certs
+	$(if $(CONFIG_OPKGSMIME_CERT),$(INSTALL_DATA) $(call qstrip,$(CONFIG_OPKGSMIME_CERT)) $(1)/etc/ssl/certs/opkg.pem,)
+endef
 
 define Build/InstallDev
 	mkdir -p $(1)/usr/include
diff --git a/package/system/opkg/files/opkg-smime.conf b/package/system/opkg/files/opkg-smime.conf
index 103f231842..849bb65b20 100644
--- a/package/system/opkg/files/opkg-smime.conf
+++ b/package/system/opkg/files/opkg-smime.conf
@@ -4,4 +4,4 @@ dest ram /tmp
 lists_dir ext /var/opkg-lists
 option overlay_root /overlay
 option check_signature 1
-option signature_ca_path /etc/ssl/certs/
+option signature_ca_file /etc/ssl/certs/opkg.pem