diff options
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/configure.ac b/configure.ac index 9963a97d49..9272834353 100644 --- a/configure.ac +++ b/configure.ac @@ -36,6 +36,8 @@ AC_ARG_ENABLE(static-zlib, AS_HELP_STRING(--enable-static-zlib, Link against a static zlib library. Requires --with-zlib-dir)) AC_ARG_ENABLE(static-tor, AS_HELP_STRING(--enable-static-tor, Create an entirely static Tor binary. Requires --with-openssl-dir and --with-libevent-dir and --with-zlib-dir)) +AC_ARG_ENABLE(curve25519, + AS_HELP_STRING(--disable-curve25519, Build Tor with no curve25519 elliptic-curve crypto support)) if test "$enable_static_tor" = "yes"; then enable_static_libevent="yes"; @@ -638,6 +640,103 @@ if test "$upnp" = "true"; then fi fi +dnl ============================================================ +dnl We need an implementation of curve25519. + +dnl set these defaults. +have_a_curve25519=no +build_curve25519_donna=no +build_curve25519_donna_c64=no +use_curve25519_donna=no +use_curve25519_nacl=no +CURVE25519_LIBS= + +if test x$enable_curve25519 != xno; then + + dnl The best choice is using curve25519-donna-c64, but that requires + dnl that we + AC_CACHE_CHECK([whether we can use curve25519-donna-c64], + tor_cv_can_use_curve25519_donna_c64, + [AC_RUN_IFELSE( + [AC_LANG_PROGRAM([dnl + #include <stdint.h> + typedef unsigned uint128_t __attribute__((mode(TI))); + ], [dnl + uint64_t a = ((uint64_t)2000000000) * 1000000000; + uint64_t b = ((uint64_t)1234567890) << 24; + uint128_t c = ((uint128_t)a) * b; + return ((uint64_t)(c>>96)) == 522859 && + ((uint64_t)(c>>64))&0xffffffffL == 3604448702L && + ((uint64_t)(c>>32))&0xffffffffL == 2351960064L && + ((uint64_t)(c))&0xffffffffL == 0; + ])], + [tor_cv_can_use_curve25519_donna_c64=yes], + [tor_cv_can_use_curve25519_donna_c64=no], + [AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([dnl + #include <stdint.h> + typedef unsigned uint128_t __attribute__((mode(TI))); + ], [dnl + uint64_t a = ((uint64_t)2000000000) * 1000000000; + uint64_t b = ((uint64_t)1234567890) << 24; + uint128_t c = ((uint128_t)a) * b; + return ((uint64_t)(c>>96)) == 522859 && + ((uint64_t)(c>>64))&0xffffffffL == 3604448702L && + ((uint64_t)(c>>32))&0xffffffffL == 2351960064L && + ((uint64_t)(c))&0xffffffffL == 0; + ])], + [tor_cv_can_use_curve25519_donna_c64=cross], + [tor_cv_can_use_curve25519_donna_c64=no])])]) + + AC_CACHE_CHECK([whether we can use curve25519 from nacl], + tor_cv_can_use_curve25519_nacl, + [tor_saved_LIBS="$LIBS" + LIBS="$LIBS -lnacl" + AC_LINK_IFELSE( + [AC_LANG_PROGRAM([dnl + #include <crypto_scalarmult_curve25519.h> + #ifdef crypto_scalarmult_curve25519_ref_BYTES + #error Hey, this is the reference implementation! + #endif + ], [ + unsigned char *a, *b, *c; crypto_scalarmult_curve25519(a,b,c); + ])], [tor_cv_can_use_curve25519_nacl=yes], + [tor_cv_can_use_curve25519_nacl=no]) + LIBS="$tor_saved_LIBS" ]) + + dnl Okay, now we need to figure out which one to actually use. Fall back + dnl to curve25519-donna.c + + if test x$tor_cv_can_use_curve25519_donna_c64 != xno; then + build_curve25519_donna_c64=yes + use_curve25519_donna=yes + elif test x$tor_cv_can_use_curve25519_nacl = xyes; then + use_curve25519_nacl=yes + CURVE25519_LIBS=-lnacl + else + build_curve25519_donna=yes + use_curve25519_donna=yes + fi + have_a_curve25519=yes +fi + +if test x$have_a_curve25519 = xyes; then + AC_DEFINE(CURVE25519_ENABLED, 1, + [Defined if we have a curve25519 implementation]) +fi +if test x$use_curve25519_donna = xyes; then + AC_DEFINE(USE_CURVE25519_DONNA, 1, + [Defined if we should use an internal curve25519_donna{,_c64} implementation]) +fi +if test x$use_curve25519_nacl = xyes; then + AC_DEFINE(USE_CURVE25519_NACL, 1, + [Defined if we should use a curve25519 from nacl]) +fi +AM_CONDITIONAL(BUILD_CURVE25519_DONNA, test x$build_curve25519_donna = xyes) +AM_CONDITIONAL(BUILD_CURVE25519_DONNA_C64, test x$build_curve25519_donna_c64 = xyes) +AM_CONDITIONAL(CURVE25519_ENABLED, test x$have_a_curve25519 = xyes) +AC_SUBST(CURVE25519_LIBS) + dnl Make sure to enable support for large off_t if available. AC_SYS_LARGEFILE |