Place /etc/passwd file inside the container for root user

This is needed because ssh requires the user that runs it to exist in /etc/passwd.

.gitignore

@@ -1,2 +1,3 @@
 *~
 *.tar.gz
+passwd

Dockerfile

@@ -1,6 +1,7 @@
 FROM scratch
 ADD guix-tarball-pack.tar.gz /guix-builder
 ADD links.tar.gz /
+ADD passwd /etc/passwd
 
 VOLUME /var/guix/daemon-socket/socket /gnu/store /etc/ssl
 ENTRYPOINT ["/guix-builder/bin/bash"]

Makefile

@@ -5,8 +5,12 @@ GUIX_MANIFEST_DEV := manifest-dev.scm
 
 TARBALL ?= guix-tarball-pack.tar.gz
 LINKS_TARBALL ?= links.tar.gz
+PASSWD_FILE ?= passwd
 IMAGE_TAG ?= guix-builder
 
+$(PASSWD_FILE):
+	echo 'root:x:0:0:root:/root:/bin/sh' > passwd
+
 $(LINKS_TARBALL):
 	ln -s /guix-builder/bin bin
 	tar -czvf $@ bin
@@ -17,7 +21,7 @@ $(TARBALL):
 	@chmod +w $@
 
 .PHONY: build
-build: $(TARBALL) $(LINKS_TARBALL)
+build: $(TARBALL) $(LINKS_TARBALL) $(PASSWD_FILE)
 	@docker build -t $(IMAGE_TAG) .
 
 .PHONY: run
@@ -36,4 +40,4 @@ shell:
 
 .PHONY:
 clean:
-	rm -r $(TARBALL) $(LINKS_TARBALL)
+	rm -r $(TARBALL) $(LINKS_TARBALL) $(PASSWD_FILE)