cargo-online-mode configure argument

Passing --enable-cargo-online-mode during configure allows cargo to make
network requests while building Tor or running tests. If this flag is
not supplied, the dependencies need to be available in the form of a
local mirror.

configure.ac

@@ -57,6 +57,8 @@ AC_ARG_ENABLE(memory-sentinels,
    AS_HELP_STRING(--disable-memory-sentinels, [disable code that tries to prevent some kinds of memory access bugs. For fuzzing only.]))
 AC_ARG_ENABLE(rust,
    AS_HELP_STRING(--enable-rust, [enable rust integration]))
+AC_ARG_ENABLE(cargo-online-mode,
+   AS_HELP_STRING(--enable-cargo-online-mode, [Allow cargo to make network requests to fetch crates. For builds with rust only.]))
 
 if test "x$enable_coverage" != "xyes" -a "x$enable_asserts_in_tests" = "xno" ; then
     AC_MSG_ERROR([Can't disable assertions outside of coverage build])
@@ -267,6 +269,12 @@ if test "x$enable_rust" = "xyes"; then
   fi
 
   AC_DEFINE([HAVE_RUST], 1, [have Rust])
+  if test "x$enable_cargo_online_mode" = "xyes"; then
+    CARGO_ONLINE=
+  else
+    CARGO_ONLINE=--frozen
+  fi
+  AC_SUBST(CARGO_ONLINE)
 fi
 
 ifdef([AC_C_FLEXIBLE_ARRAY_MEMBER], [

src/rust/tor_util/include.am

@@ -7,6 +7,6 @@ EXTRA_DIST +=\
 src/rust/target/release/libtor_util.a: FORCE
 	( cd "$(abs_top_srcdir)/src/rust/tor_util" ; \
 		CARGO_TARGET_DIR="$(abs_top_builddir)/src/rust/target" \
-		$(CARGO) build --release --quiet --frozen )
+		$(CARGO) build --release --quiet $(CARGO_ONLINE) )
 
 FORCE:

src/test/include.am

@@ -7,7 +7,8 @@ TESTS_ENVIRONMENT = \
 	export abs_top_srcdir="$(abs_top_srcdir)"; \
 	export builddir="$(builddir)"; \
 	export TESTING_TOR_BINARY="$(TESTING_TOR_BINARY)"; \
-	export CARGO="$(CARGO)";
+	export CARGO="$(CARGO)"; \
+	export CARGO_ONLINE="$(CARGO_ONLINE)";
 
 TESTSCRIPTS = \
 	src/test/fuzz_static_testcases.sh \

src/test/test_rust.sh

@@ -7,7 +7,7 @@ exitcode=0
 
 for crate in $crates; do
     cd "${abs_top_srcdir:-.}/src/rust/${crate}"
-    "${CARGO:-cargo}" test --frozen || exitcode=1
+    "${CARGO:-cargo}" test ${CARGO_ONLINE-"--frozen"} || exitcode=1
 done
 
 exit $exitcode