diff --git a/Makefile b/Makefile
index 379086d..02300fa 100644
--- a/Makefile
+++ b/Makefile
@@ -21,6 +21,14 @@ chroots:
 	for DIST in wheezy jessie; do \
 		for ARCH in i386 amd64; do \
 			mkdir -p /var/cache/pbuilder/$$DIST-$$ARCH/base.cow; \
-			DIST=$$DIST ARCH=$$ARCH cowbuilder --create --configfile ./pbuilderrc; \
+			DIST=$$DIST ARCH=$$ARCH cowbuilder --create --configfile ./pbuilderrc --keyring ./entrouvert.gpg; \
+		done; \
+	done
+
+chroots-update:
+	for DIST in wheezy jessie; do \
+		for ARCH in i386 amd64; do \
+			mkdir -p /var/cache/pbuilder/$$DIST-$$ARCH/base.cow; \
+			DIST=$$DIST ARCH=$$ARCH cowbuilder --update --configfile ./pbuilderrc --keyring ./entrouvert.gpg; \
 		done; \
 	done
diff --git a/entrouvert.gpg b/entrouvert.gpg
new file mode 100644
index 0000000..cf40249
Binary files /dev/null and b/entrouvert.gpg differ