commit 90cd878468554a5c9dd52718a74f401238120748 Author: David Goulet dgoulet@ev0ke.net Date: Sat Nov 9 15:35:58 2013 -0500

Fix: lookup libc name and pass it to dlopen()

The configure process now looks up the libc file name on a per OS basis and this value is passed to dlopen() that handles the library lookup in the system like stated in dlopen(3).

Fixes #12

Signed-off-by: David Goulet dgoulet@ev0ke.net --- configure.ac | 41 +++++++++++++++-------------------------- src/lib/torsocks.c | 6 +++--- 2 files changed, 18 insertions(+), 29 deletions(-)

diff --git a/configure.ac b/configure.ac index c02ffda..a6b7138 100644 --- a/configure.ac +++ b/configure.ac @@ -115,34 +115,23 @@ if test "x${enable_envconf}" = "x"; then AC_DEFINE([ALLOW_ENV_CONFIG],[],[Description]) fi

-dnl Check that find is available, it should be somehere -dnl in the path -AC_CHECK_PROG(FIND, find, find) -if test "${FIND}" = ""; then - AC_MSG_ERROR('find not found in path') -fi - -dnl Find tail, it should always be somewhere in the path -dnl but for safety's sake -AC_CHECK_PROG(TAIL, tail, tail) -if test "${TAIL}" = ""; then - AC_MSG_ERROR('tail not found in path') -fi - dnl Get libc full system path. Use prefix or some hardcoded standard dnl location on Unixish system. -AC_MSG_CHECKING(location of libc.so) -for DIR in "$prefix/lib" "$prefix/usr/lib" '/lib' '/usr/lib'; do - if test "${LIBC_PATH}" = ""; then - LIBC_PATH=`$FIND $DIR -name "libc.so.?" 2>/dev/null | $TAIL -1` - fi -done -AC_DEFINE_UNQUOTED([LIBC_PATH],["${LIBC_PATH}"],[Description]) -if test "${LIBC_PATH}" = ""; then - AC_MSG_ERROR("not found!") -fi - -AC_MSG_RESULT($LIBC_PATH) +AC_MSG_CHECKING(file name of the C library) +AS_CASE([$host_os], + [darwin*], [libc_name="libSystem.dylib"], + [linux*], + [ + libc_name=`ldd /bin/ls | grep libc | cut -d ' ' -f 1 | tr -d '\t'` + if test "${libc_name}" == ""; then + # Default libc on most system. + libc_name="libc.so.6" + fi + ], + [libc_name="libc.so"] +) +AC_DEFINE_UNQUOTED([LIBC_NAME],["${libc_name}"], [Description]) +AC_MSG_RESULT($libc_name)

############################################################################## # 5. Determine how to preload libtorsocks.so on this system. diff --git a/src/lib/torsocks.c b/src/lib/torsocks.c index 93c2c35..332c561 100644 --- a/src/lib/torsocks.c +++ b/src/lib/torsocks.c @@ -123,9 +123,9 @@ static void init_libc_symbols(void) void *libc_ptr;

dlerror(); - libc_ptr = dlopen(LIBC_PATH, RTLD_LAZY); + libc_ptr = dlopen(LIBC_NAME, RTLD_LAZY); if (!libc_ptr) { - ERR("Unable to dlopen() library " LIBC_PATH "(%s)", dlerror()); + ERR("Unable to dlopen() library " LIBC_NAME "(%s)", dlerror()); goto error; }

@@ -136,7 +136,7 @@ static void init_libc_symbols(void) tsocks_libc_syscall = dlsym(libc_ptr, LIBC_SYSCALL_NAME_STR); if (!tsocks_libc_connect || !tsocks_libc_close || !tsocks_libc_socket || !tsocks_libc_syscall) { - ERR("Unable to lookup symbols in " LIBC_PATH "(%s)", dlerror()); + ERR("Unable to lookup symbols in " LIBC_NAME "(%s)", dlerror()); goto error; }