Add -ftrapv to gcc-hardening ... mostly!

We know there are overflows in curve25519-donna-c32, so we'll have
to have that one be fwrapv.

Only apply the asan, ubsan, and trapv options to the code that does
not need to run in constant time.  Those options introduce branches
to the code they instrument.

(These introduced branches should never actually be taken, so it
might _still_ be constant time after all, but branch predictors are
complicated enough that I'm not really confident here. Let's aim for
safety.)

Closes 17983.

5 files changed, 37 insertions, 9 deletions

diff --git a/src/common/include.am b/src/common/include.am
index 5afb30da6a..96fc329aae 100644
--- a/src/common/include.am
+++ b/src/common/include.am
@@ -1,12 +1,14 @@
 
 noinst_LIBRARIES += \
 	src/common/libor.a \
+        src/common/libor-ctime.a \
 	src/common/libor-crypto.a \
 	src/common/libor-event.a
 
 if UNITTESTS_ENABLED
 noinst_LIBRARIES += \
 	src/common/libor-testing.a \
+        src/common/libor-ctime-testing.a \
 	src/common/libor-crypto-testing.a \
 	src/common/libor-event-testing.a
 endif
@@ -27,12 +29,14 @@ src_common_libcurve25519_donna_a_CFLAGS=
 if BUILD_CURVE25519_DONNA
 src_common_libcurve25519_donna_a_SOURCES=\
 	src/ext/curve25519_donna/curve25519-donna.c
+# See bug 13538 -- this code is known to have signed overflow issues.
 src_common_libcurve25519_donna_a_CFLAGS+=\
-	@F_OMIT_FRAME_POINTER@
+	@F_OMIT_FRAME_POINTER@ @CFLAGS_CONSTTIME@
 noinst_LIBRARIES+=src/common/libcurve25519_donna.a
 LIBDONNA=src/common/libcurve25519_donna.a
 else
 if BUILD_CURVE25519_DONNA_C64
+src_common_libcurve25519_donna_a_CFLAGS+=@CFLAGS_CONSTTIME@
 src_common_libcurve25519_donna_a_SOURCES=\
 	src/ext/curve25519_donna/curve25519-donna-c64.c
 noinst_LIBRARIES+=src/common/libcurve25519_donna.a
@@ -58,13 +62,21 @@ else
 readpassphrase_source=
 endif
 
+LIBOR_CTIME_A_SOURCES = \
+   src/ext/csiphash.c   \
+   src/common/di_ops.c
+
+src_common_libor_ctime_a_SOURCES = $(LIBOR_CTIME_A_SOURCES)
+src_common_libor_ctime_testing_a_SOURCES = $(LIBOR_CTIME_A_SOURCES)
+src_common_libor_ctime_a_CFLAGS = @CFLAGS_CONSTTIME@
+src_common_libor_ctime_testing_a_CFLAGS = @CFLAGS_CONSTTIME@ $(TEST_CFLAGS)
+
 LIBOR_A_SOURCES = \
   src/common/address.c					\
   src/common/backtrace.c				\
   src/common/compat.c					\
   src/common/compat_threads.c				\
   src/common/container.c				\
-  src/common/di_ops.c					\
   src/common/log.c					\
   src/common/memarea.c					\
   src/common/util.c					\
@@ -72,7 +84,6 @@ LIBOR_A_SOURCES = \
   src/common/util_process.c				\
   src/common/sandbox.c					\
   src/common/workqueue.c				\
-  src/ext/csiphash.c					\
   src/ext/trunnel/trunnel.c				\
   $(libor_extra_source)					\
   $(threads_impl_source)				\
diff --git a/src/ext/include.am b/src/ext/include.am
index bf678f2c9d..2a0227a85a 100644
--- a/src/ext/include.am
+++ b/src/ext/include.am
@@ -16,7 +16,8 @@ EXTHEADERS = \
 
 noinst_HEADERS+= $(EXTHEADERS)
 
-src_ext_ed25519_ref10_libed25519_ref10_a_CFLAGS=
+src_ext_ed25519_ref10_libed25519_ref10_a_CFLAGS=\
+  @CFLAGS_CONSTTIME@
 
 src_ext_ed25519_ref10_libed25519_ref10_a_SOURCES= \
 	src/ext/ed25519/ref10/fe_0.c \
@@ -93,7 +94,8 @@ noinst_HEADERS += $(ED25519_REF10_HDRS)
 LIBED25519_REF10=src/ext/ed25519/ref10/libed25519_ref10.a
 noinst_LIBRARIES += $(LIBED25519_REF10)
 
-src_ext_ed25519_donna_libed25519_donna_a_CFLAGS= \
+src_ext_ed25519_donna_libed25519_donna_a_CFLAGS=\
+  @CFLAGS_CONSTTIME@ \
   -DED25519_CUSTOMRANDOM \
   -DED25519_SUFFIX=_donna
 
@@ -135,7 +137,8 @@ noinst_HEADERS += $(ED25519_DONNA_HDRS)
 LIBED25519_DONNA=src/ext/ed25519/donna/libed25519_donna.a
 noinst_LIBRARIES += $(LIBED25519_DONNA)
 
-src_ext_keccak_tiny_libkeccak_tiny_a_CFLAGS=
+src_ext_keccak_tiny_libkeccak_tiny_a_CFLAGS=\
+  @CFLAGS_CONSTTIME@
 
 src_ext_keccak_tiny_libkeccak_tiny_a_SOURCES= \
 	src/ext/keccak-tiny/keccak-tiny-unrolled.c
diff --git a/src/or/include.am b/src/or/include.am
index 712ae18406..19f1a7fe0a 100644
--- a/src/or/include.am
+++ b/src/or/include.am
@@ -109,7 +109,7 @@ src_or_libtor_testing_a_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
 
 
 src_or_tor_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@ @TOR_LDFLAGS_libevent@
-src_or_tor_LDADD = src/or/libtor.a src/common/libor.a \
+src_or_tor_LDADD = src/or/libtor.a src/common/libor.a src/common/libor-ctime.a \
 	src/common/libor-crypto.a $(LIBKECCAK_TINY) $(LIBDONNA) \
 	src/common/libor-event.a src/trunnel/libor-trunnel.a \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ @TOR_OPENSSL_LIBS@ \
@@ -121,6 +121,7 @@ src_or_tor_cov_CPPFLAGS = $(AM_CPPFLAGS) $(TEST_CPPFLAGS)
 src_or_tor_cov_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
 src_or_tor_cov_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@ @TOR_LDFLAGS_libevent@
 src_or_tor_cov_LDADD = src/or/libtor-testing.a src/common/libor-testing.a \
+	src/common/libor-ctime-testing.a \
 	src/common/libor-crypto-testing.a $(LIBKECCAK_TINY) $(LIBDONNA) \
 	src/common/libor-event-testing.a src/trunnel/libor-trunnel-testing.a \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ @TOR_OPENSSL_LIBS@ \
diff --git a/src/test/include.am b/src/test/include.am
index 7d80fdf152..c4ef30fe0d 100644
--- a/src/test/include.am
+++ b/src/test/include.am
@@ -147,6 +147,7 @@ src_test_test_switch_id_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
 src_test_test_switch_id_LDFLAGS = @TOR_LDFLAGS_zlib@
 src_test_test_switch_id_LDADD = \
 	src/common/libor-testing.a \
+	src/common/libor-ctime-testing.a \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@
 
 src_test_test_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@ \
@@ -156,6 +157,7 @@ src_test_test_LDADD = src/or/libtor-testing.a \
 	$(LIBKECCAK_TINY) \
 	$(LIBDONNA) \
 	src/common/libor-testing.a \
+	src/common/libor-ctime-testing.a \
 	src/common/libor-event-testing.a \
 	src/trunnel/libor-trunnel-testing.a \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ \
@@ -175,6 +177,7 @@ src_test_test_memwipe_LDFLAGS = $(src_test_test_LDFLAGS)
 src_test_bench_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@ \
         @TOR_LDFLAGS_libevent@
 src_test_bench_LDADD = src/or/libtor.a src/common/libor.a \
+	src/common/libor-ctime.a \
 	src/common/libor-crypto.a $(LIBKECCAK_TINY) $(LIBDONNA) \
 	src/common/libor-event.a src/trunnel/libor-trunnel.a \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ \
@@ -185,6 +188,7 @@ src_test_test_workqueue_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@ \
         @TOR_LDFLAGS_libevent@
 src_test_test_workqueue_LDADD = src/or/libtor-testing.a \
 	src/common/libor-testing.a \
+	src/common/libor-ctime-testing.a \
 	src/common/libor-crypto-testing.a $(LIBKECCAK_TINY) $(LIBDONNA) \
 	src/common/libor-event-testing.a \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ @TOR_LIBEVENT_LIBS@ \
@@ -208,6 +212,7 @@ noinst_PROGRAMS+= src/test/test-ntor-cl
 src_test_test_ntor_cl_SOURCES  = src/test/test_ntor_cl.c
 src_test_test_ntor_cl_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@
 src_test_test_ntor_cl_LDADD = src/or/libtor.a src/common/libor.a \
+	src/common/libor-ctime.a \
 	src/common/libor-crypto.a $(LIBKECCAK_TINY) $(LIBDONNA) \
 	@TOR_ZLIB_LIBS@ @TOR_LIB_MATH@ \
 	@TOR_OPENSSL_LIBS@ @TOR_LIB_WS32@ @TOR_LIB_GDI@ @CURVE25519_LIBS@
@@ -217,6 +222,7 @@ src_test_test_ntor_cl_AM_CPPFLAGS =	       \
 noinst_PROGRAMS += src/test/test-bt-cl
 src_test_test_bt_cl_SOURCES = src/test/test_bt_cl.c
 src_test_test_bt_cl_LDADD = src/common/libor-testing.a \
+	src/common/libor-ctime-testing.a \
 	@TOR_LIB_MATH@ \
 	@TOR_LIB_WS32@ @TOR_LIB_GDI@
 src_test_test_bt_cl_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
diff --git a/src/tools/include.am b/src/tools/include.am
index 38ed57546f..b4ea82d355 100644
--- a/src/tools/include.am
+++ b/src/tools/include.am
@@ -7,19 +7,23 @@ endif
 
 src_tools_tor_resolve_SOURCES = src/tools/tor-resolve.c
 src_tools_tor_resolve_LDFLAGS =
-src_tools_tor_resolve_LDADD = src/common/libor.a @TOR_LIB_MATH@ @TOR_LIB_WS32@
+src_tools_tor_resolve_LDADD = src/common/libor.a \
+	src/common/libor-ctime.a \
+	@TOR_LIB_MATH@ @TOR_LIB_WS32@
 
 if COVERAGE_ENABLED
 src_tools_tor_cov_resolve_SOURCES = src/tools/tor-resolve.c
 src_tools_tor_cov_resolve_CPPFLAGS = $(AM_CPPFLAGS) $(TEST_CPPFLAGS)
 src_tools_tor_cov_resolve_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
 src_tools_tor_cov_resolve_LDADD = src/common/libor-testing.a \
+	src/common/libor-ctime-testing.a \
         @TOR_LIB_MATH@ @TOR_LIB_WS32@
 endif
 
 src_tools_tor_gencert_SOURCES = src/tools/tor-gencert.c
 src_tools_tor_gencert_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@
 src_tools_tor_gencert_LDADD = src/common/libor.a src/common/libor-crypto.a \
+    src/common/libor-ctime.a \
     $(LIBKECCAK_TINY) \
     $(LIBDONNA) \
         @TOR_LIB_MATH@ @TOR_ZLIB_LIBS@ @TOR_OPENSSL_LIBS@ \
@@ -31,6 +35,7 @@ src_tools_tor_cov_gencert_CPPFLAGS = $(AM_CPPFLAGS) $(TEST_CPPFLAGS)
 src_tools_tor_cov_gencert_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS)
 src_tools_tor_cov_gencert_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@
 src_tools_tor_cov_gencert_LDADD = src/common/libor-testing.a \
+    src/common/libor-ctime-testing.a \
     src/common/libor-crypto-testing.a \
     $(LIBKECCAK_TINY) \
     $(LIBDONNA) \
@@ -40,7 +45,9 @@ endif
 
 src_tools_tor_checkkey_SOURCES = src/tools/tor-checkkey.c
 src_tools_tor_checkkey_LDFLAGS = @TOR_LDFLAGS_zlib@ @TOR_LDFLAGS_openssl@
-src_tools_tor_checkkey_LDADD = src/common/libor.a src/common/libor-crypto.a \
+src_tools_tor_checkkey_LDADD = src/common/libor.a \
+    src/common/libor-ctime.a \
+    src/common/libor-crypto.a \
     $(LIBKECCAK_TINY) \
     $(LIBDONNA) \
         @TOR_LIB_MATH@ @TOR_ZLIB_LIBS@ @TOR_OPENSSL_LIBS@ \