/* Copyright (c) 2003-2004, Roger Dingledine

 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.

 * Copyright (c) 2007-2021, The Tor Project, Inc. */

/* See LICENSE for licensing information */

/**

 * \file uname.c

 * \brief Look up a description of the operating system.

 **/

#include "orconfig.h"

#include "lib/osinfo/uname.h"

#include "lib/string/compat_string.h"

#include "lib/string/printf.h"

#ifdef HAVE_UNAME

#include <sys/utsname.h>

#endif

#ifdef _WIN32

#include <windows.h>

#endif

#include <string.h>

/** Hold the result of our call to <b>uname</b>. */

static char uname_result[256];

/** True iff uname_result is set. */

static int uname_result_is_set = 0;

#ifdef _WIN32

/** Table to map claimed windows versions into human-readable windows

 * versions. */

static struct {

  unsigned major;

  unsigned minor;

  const char *client_version;

  const char *server_version;

} win_version_table[] = {

  /* This table must be sorted in descending order.

   * Sources:

   *   https://en.wikipedia.org/wiki/List_of_Microsoft_Windows_versions

   *   https://docs.microsoft.com/en-us/windows/desktop/api/winnt/

   *     ns-winnt-_osversioninfoexa#remarks

   */

   /* Windows Server 2019 is indistinguishable from Windows Server 2016

    * using GetVersionEx().

   { 10,  0, NULL,                        "Windows Server 2019" }, */

   // clang-format off

   { 10,  0, "Windows 10",                "Windows Server 2016" },

   {  6,  3, "Windows 8.1",               "Windows Server 2012 R2" },

   {  6,  2, "Windows 8",                 "Windows Server 2012" },

   {  6,  1, "Windows 7",                 "Windows Server 2008 R2" },

   {  6,  0, "Windows Vista",             "Windows Server 2008" },

   {  5,  2, "Windows XP Professional",   "Windows Server 2003" },

   /* Windows XP did not have a server version, but we need something here */

   {  5,  1, "Windows XP",                "Windows XP Server" },

   {  5,  0, "Windows 2000 Professional", "Windows 2000 Server" },

   /* Earlier versions are not supported by GetVersionEx(). */

   {  0,  0, NULL,                        NULL }

   // clang-format on

};

#endif /* defined(_WIN32) */

/** Return a pointer to a description of our platform.

 */

MOCK_IMPL(const char *,

get_uname,(void))

{

#ifdef HAVE_UNAME

  struct utsname u;

#endif

  if (!uname_result_is_set) {

#ifdef HAVE_UNAME

    if (uname(&u) != -1) {

      /* (Linux says 0 is success, Solaris says 1 is success) */

      strlcpy(uname_result, u.sysname, sizeof(uname_result));

    } else

#endif /* defined(HAVE_UNAME) */

      {

#ifdef _WIN32

        OSVERSIONINFOEX info;

        int i;

        int is_client = 0;

        int is_server = 0;

        const char *plat = NULL;

        memset(&info, 0, sizeof(info));

        info.dwOSVersionInfoSize = sizeof(info);

        if (! GetVersionEx((LPOSVERSIONINFO)&info)) {

          strlcpy(uname_result, "Bizarre version of Windows where GetVersionEx"

                  " doesn't work.", sizeof(uname_result));

          uname_result_is_set = 1;

          return uname_result;

        }

#ifdef VER_NT_SERVER

        if (info.wProductType == VER_NT_SERVER ||

            info.wProductType == VER_NT_DOMAIN_CONTROLLER) {

          is_server = 1;

        } else {

          is_client = 1;

        }

#endif /* defined(VER_NT_SERVER) */

        /* Search the version table for a matching version */

        for (i=0; win_version_table[i].major>0; ++i) {

          if (win_version_table[i].major == info.dwMajorVersion &&

              win_version_table[i].minor == info.dwMinorVersion) {

            if (is_server) {

              plat = win_version_table[i].server_version;

            } else {

              /* Use client versions for clients, and when we don't know if it

              * is a client or a server. */

              plat = win_version_table[i].client_version;

            }

            break;

          }

        }

        if (plat) {

          strlcpy(uname_result, plat, sizeof(uname_result));

        } else {

          if (info.dwMajorVersion > win_version_table[0].major ||

              (info.dwMajorVersion == win_version_table[0].major &&

               info.dwMinorVersion > win_version_table[0].minor))

            tor_snprintf(uname_result, sizeof(uname_result),

                         "Very recent version of Windows [major=%d,minor=%d]",

                         (int)info.dwMajorVersion,(int)info.dwMinorVersion);

          else

            tor_snprintf(uname_result, sizeof(uname_result),

                         "Unrecognized version of Windows [major=%d,minor=%d]",

                         (int)info.dwMajorVersion,(int)info.dwMinorVersion);

        }

        /* Now append extra information to the name.

         *

         * Microsoft's API documentation says that on Windows 8.1 and later,

         * GetVersionEx returns Windows 8 (6.2) for applications without an

         * app compatibility manifest (including tor's default build).

         *

         * But in our testing, we have seen the actual Windows version on

         * Windows Server 2012 R2, even without a manifest. */

        if (info.dwMajorVersion > 6 ||

            (info.dwMajorVersion == 6 && info.dwMinorVersion >= 2)) {

          /* When GetVersionEx() returns Windows 8, the actual OS may be any

           * later version. */

          strlcat(uname_result, " [or later]", sizeof(uname_result));

        }

        /* When we don't know if the OS is a client or server version, we use

         * the client version, and this qualifier. */

        if (!is_server && !is_client) {

          strlcat(uname_result, " [client or server]", sizeof(uname_result));

        }

#else /* !defined(_WIN32) */

        /* LCOV_EXCL_START -- can't provoke uname failure */

        strlcpy(uname_result, "Unknown platform", sizeof(uname_result));

        /* LCOV_EXCL_STOP */

#endif /* defined(_WIN32) */

      }

    uname_result_is_set = 1;

  }

  return uname_result;

}