/*
  *  Detect environment for bytecode.
  *
  *  Copyright (C) 2009-2010 Sourcefire, Inc.
  *
  *  Authors: Török Edvin
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2 as
  *  published by the Free Software Foundation.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  *  MA 02110-1301, USA.
  */
 
 #if HAVE_CONFIG_H
 #include "clamav-config.h"
 #endif
 #include "target.h"
 #include "cltypes.h"
 
 #include "bytecode_detect.h"
 #include "others.h"
 #include <string.h>
 #include <stdio.h>

 #include <errno.h>

 
 #ifdef HAVE_UNAME_SYSCALL
 #include <sys/utsname.h>
 #endif
 
 #define CHECK_ARCH(a) if (!strcmp(TARGET_ARCH_TYPE, #a)) env->arch = arch_##a
 
 extern int have_clamjit;
 
 static void cli_print_environment(struct cli_environment *env)
 {
     uint32_t id_a = env->platform_id_a;
     uint32_t id_b = env->platform_id_b;
     uint32_t id_c = env->platform_id_c;
     /* the bytecode instruction that exactly identifies this platform */
     /* the space separated groups can be a concrete value, or 0xff for ANY */
     cli_dbgmsg("environment detected:\n");
     cli_dbgmsg("check_platform(0x%08x, 0x%08x, 0x%08x)\n",
 	       id_a, id_b, id_c);
     cli_dbgmsg("check_platform(0x%02x  %01x  %01x  %02x  %02x,"
 	       "0x%01x  %01x       %02x %02x %02x,"
 	       "0x%02x    %02x %02x %02x)\n",
 	       env->os_category, env->arch, env->compiler,
 	       env->functionality_level,
 	       env->dconf_level,
                env->big_endian,
                env->sizeof_ptr,
 	       (env->cpp_version >> 16)&0xff,
 	       (env->cpp_version >> 8)&0xff,
 	       env->cpp_version&0xff,
 	       env->os_features,
 	       (env->c_version >> 16)&0xff,
 	       (env->c_version >> 8)&0xff,
 	       env->c_version&0xff);
     cli_dbgmsg("check_platform( OS CPU COM FL DCONF,BE PTR CXX VV.VV.VV, FLG CC VV.VV.VV)\n");
     cli_dbgmsg("Engine version: %s\n", env->engine_version);
     cli_dbgmsg("Host triple: %s\n", env->triple);
     cli_dbgmsg("Host CPU: %s\n", env->cpu);
     cli_dbgmsg("OS: %s\n", env->sysname);
     cli_dbgmsg("OS release: %s\n", env->release);
     cli_dbgmsg("OS version: %s\n", env->version);
     cli_dbgmsg("OS hardware: %s\n", env->machine);
     cli_dbgmsg("OS LLVM category: %d\n", env->os);
     cli_dbgmsg("Has JIT compiled: %d\n", env->has_jit_compiled);
     cli_dbgmsg("------------------------------------------------------\n");
 }
 
 #ifdef __linux__
 
 static int detect_PaX(void)
 {
     char line[128];
     int pax = 0;
     FILE *f = fopen("/proc/self/status", "r");
     if (!f)
 	return 0;
     while (fgets(line, sizeof(line), f)) {
 	if (!memcmp(line, "PaX:", 4)) {
 	    pax = 1;
 	    if (!strchr(line,'m'))
 		pax = 2;
 	    break;
 	}
     }
     fclose(f);

     return pax;

 }
 
 static int detect_SELinux(void)
 {
     char line[128];
     int selinux = 0;
     int enforce = 0;
     FILE *f = fopen("/proc/filesystems", "r");

     if (!f) {
 	f = fopen("/selinux/enforce", "r");
         if (!f && errno == EACCES)
 		return 2;

 	if (f) {
 	    if (fscanf(f, "%d", &enforce) == 1)

 		selinux = 2;

 	    fclose(f);
 	}

 	return selinux;
     }

     while (fgets(line, sizeof(line), f)) {

 	if (strstr(line, "selinuxfs\n")) {

 	    selinux = 1;
 	    break;
 	}
     }
     fclose(f);
     if (!selinux)
 	return 0;
 
     f = fopen("/selinux/enforce", "r");
     if (f && fscanf(f, "%d", &enforce) == 1) {
 	if (enforce == 1)
 	    selinux = 2;
 	if (enforce == -1)
 	    selinux = 0;

 	fclose(f);

     }
     return selinux;
 }
 
 static void detect_os_features(uint8_t *os_features)
 {
     int features = 0;
     switch (detect_PaX()) {
 	case 2:
 	    features |= 1 << feature_pax_mprotect;
 	    /* fall through */
 	case 1:
 	    features |= 1 << feature_pax;
 	    break;
 	default:
 	    break;
     }
     switch (detect_SELinux()) {
 	case 2:
 	    features |= 1 << feature_selinux_enforcing;
 	    /* fall through */
 	case 1:
 	    features |= 1 << feature_selinux;
 	    break;
 	default:
 	    break;
     }
 
     *os_features = features;
 }
 #else
 static void detect_os_features(uint8_t *os_features)
 {
     *os_features = 0;
 }
 #endif
 
 /* OS features : 
  * Linux: PaX << 2| SELinux << 1| mmap-RWX
  * Other:                         mmap-RWX */
 
 void cli_detect_environment(struct cli_environment *env)
 {
     memset(env, 0, sizeof(*env));
 #if WORDS_BIGENDIAN == 0
     env->big_endian = 0;
 #else
     env->big_endian = 1;
 #endif
     env->sizeof_ptr = sizeof(void*);
 
     /* -- Detect arch -- */
     CHECK_ARCH(i386);
     else CHECK_ARCH(x86_64);

     else if (!strcmp(TARGET_ARCH_TYPE,"amd64")) env->arch = arch_x86_64;

     else if (!strcmp(TARGET_ARCH_TYPE,"ppc")) env->arch = arch_ppc32;/* llvm will fix ppc64 */
     else CHECK_ARCH(arm);
     else CHECK_ARCH(sparc);
     else CHECK_ARCH(sparc64);
     else CHECK_ARCH(mips);
     else CHECK_ARCH(mips64);
     else CHECK_ARCH(alpha);
     else CHECK_ARCH(hppa1);
     else CHECK_ARCH(hppa2);
     else CHECK_ARCH(m68k);
     else env->arch = arch_unknown;
 
     /* -- Detect OS -- */
 #ifdef C_AIX
     env->os_category = os_aix;
 #elif defined(C_BEOS)
     env->os_category = os_beos;
     /* DARWIN must come before BSD since it defines both */
 #elif defined(C_DARWIN)
     env->os_category = os_darwin;
 #elif defined(C_BSD)
     env->os_category = os_bsd;
 #elif defined(C_GNU_HURD)
     env->os_category = os_gnu_hurd;
 #elif defined(C_HPUX)
     env->os_category = os_hpux;
 #elif defined(C_INTERIX)
     env->os_category = os_interix;
 #elif defined(C_IRIX)
     env->os_category = os_irix;
 #elif defined(C_KFREEBSD_GNU)
     env->os_category = os_kfreebsd_gnu;
 #elif defined(C_LINUX)
     env->os_category = os_linux;
 #elif defined(C_OS2)
     env->os_category = os_os2;
 #elif defined(C_OSF)
     env->os_category = os_osf;
 #elif defined(C_QNX6)
     env->os_category = os_qnx6;
 #elif defined(C_SOLARIS)
     env->os_category = os_solaris;
 #elif defined(_WIN64)
     env->os_category = os_win64;
 #elif defined(_WIN32)
     env->os_category = os_win32;
 #else
     env->os_category = os_generic;
 #endif
 
     env->os = llvm_os_UnknownOS;
     /* -- Detect compiler -- */
 
     /* check GNUC last, because some other compilers might define it */
 #ifdef __INTEL_COMPILER
     env->compiler = compiler_intel;
     env->c_version = __INTEL_COMPILER;
 #elif defined(_MSC_VER)
     env->compiler = compiler_msc;
     env->c_version = _MSC_VER;
 #elif defined(__SUNPRO_C)
     env->compiler = compiler_sun;
     env->c_version = __SUNPRO_C;
 #elif defined(__GNUC__)
 
 #ifdef __clang__
     env->compiler = compiler_clang;
 #elif defined(__llvm__)
     env->compiler = compiler_llvm;
 #else
     env->compiler = compiler_gnuc;
 #endif
     env->c_version =
 	MAKE_VERSION(0, __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);
 
 #else
     env->compiler = compiler_other;
     env->c_version = 0;
 #endif
     env->cpp_version = 0;
 
     env->has_jit_compiled = have_clamjit;
 
     /* engine */
     env->functionality_level = cl_retflevel();
     env->dconf_level = CL_FLEVEL_DCONF;
 
     INIT_STRFIELD(env->engine_version, cl_retver());
 #ifdef HAVE_UNAME_SYSCALL
     {
 	struct utsname name;
 	if (uname(&name) == 0) {
 	    INIT_STRFIELD(env->sysname, name.sysname);
 	    INIT_STRFIELD(env->release, name.release);
 	    INIT_STRFIELD(env->version, name.version);
 	    INIT_STRFIELD(env->machine, name.machine);
 	}
     }
 #endif
 #ifdef _WIN32
     {
 	OSVERSIONINFOEX info;
 	info.dwOSVersionInfoSize = sizeof(info);

 	if (GetVersionEx((OSVERSIONINFO *)&info) != 0 && info.dwPlatformId == VER_PLATFORM_WIN32_NT) {

 	    if (info.wProductType == VER_NT_WORKSTATION)
 		INIT_STRFIELD(env->sysname, "Microsoft Windows");
 	    else
 		INIT_STRFIELD(env->sysname, "Microsoft Windows Server");

 	    snprintf((char*)env->release, sizeof(env->release), "%d.%d SP%d.%d",

 		     info.dwMajorVersion, info.dwMinorVersion,
 		     info.wServicePackMajor, info.wServicePackMinor);

 	    snprintf((char*)env->version, sizeof(env->version),"Build %d",

 		     info.dwBuildNumber);
 	}
     }

 #endif
     if (!env->sysname[0]) {
 	INIT_STRFIELD(env->sysname, TARGET_OS_TYPE);
     }
 
     detect_os_features(&env->os_features);
 
     cli_detect_env_jit(env);
 
     env->platform_id_a = (env->os_category << 24) | (env->arch << 20) |
 	(env->compiler << 16) | (env->functionality_level << 8) |
 	(env->dconf_level);
     env->platform_id_b = (env->big_endian << 28) | (env->sizeof_ptr << 24) |
       env->cpp_version;
     env->platform_id_c = (env->os_features << 24) | env->c_version;
     cli_print_environment(env);
 }