sysutil.c

linux下的轻量级的ftp服务器

}

const void*
vsf_sysutil_sockaddr_ipv6_v4(const struct vsf_sysutil_sockaddr* p_addr)
{
  static char pattern[12] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF };
  const unsigned char* p_addr_start;
  if (p_addr->u.u_sockaddr.sa_family != AF_INET6)
  {
    return 0;
  }
  if (vsf_sysutil_memcmp(pattern, &p_addr->u.u_sockaddr_in6.sin6_addr, 12))
  {
    return 0;
  }
  p_addr_start = (const unsigned char*)&p_addr->u.u_sockaddr_in6.sin6_addr;
  return &p_addr_start[12];
}

const void*
vsf_sysutil_sockaddr_ipv4_v6(const struct vsf_sysutil_sockaddr* p_addr)
{
  static char ret[16] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF };
  if (p_addr->u.u_sockaddr.sa_family != AF_INET)
  {
    return 0;
  }
  vsf_sysutil_memcpy(&ret[12], &p_addr->u.u_sockaddr_in.sin_addr, 4);
  return ret;
}

void*
vsf_sysutil_sockaddr_get_raw_addr(struct vsf_sysutil_sockaddr* p_sockptr)
{
  if (p_sockptr->u.u_sockaddr.sa_family == AF_INET)
  {
    return &p_sockptr->u.u_sockaddr_in.sin_addr;
  }
  else if (p_sockptr->u.u_sockaddr.sa_family == AF_INET6)
  {
    return &p_sockptr->u.u_sockaddr_in6.sin6_addr;
  }
  else
  {
    bug("bad family");
  }
  return 0;
}

unsigned int
vsf_sysutil_get_ipaddr_size(void)
{
  struct vsf_sysutil_sockaddr addr;
  unsigned int size = sizeof(addr.u.u_sockaddr_in.sin_addr);
  unsigned int size2 = sizeof(addr.u.u_sockaddr_in6.sin6_addr);
  if (size2 > size)
  {
    size = size2;
  }
  return size;
}

int
vsf_sysutil_get_ipsock(const struct vsf_sysutil_sockaddr* p_addr)
{
  if (p_addr->u.u_sockaddr.sa_family == AF_INET)
  {
    return vsf_sysutil_get_ipv4_sock();
  }
  else if (p_addr->u.u_sockaddr.sa_family == AF_INET6)
  {
    return vsf_sysutil_get_ipv6_sock();
  }
  else
  {
    bug("bad family");
  }
  return -1;
}

void
vsf_sysutil_sockaddr_set_any(struct vsf_sysutil_sockaddr* p_sockaddr)
{
  if (p_sockaddr->u.u_sockaddr.sa_family == AF_INET)
  {
    vsf_sysutil_memclr(&p_sockaddr->u.u_sockaddr_in.sin_addr,
                       sizeof(p_sockaddr->u.u_sockaddr_in.sin_addr));
  }
  else if (p_sockaddr->u.u_sockaddr.sa_family == AF_INET6)
  {
    vsf_sysutil_memclr(&p_sockaddr->u.u_sockaddr_in6.sin6_addr,
                       sizeof(p_sockaddr->u.u_sockaddr_in6.sin6_addr));
  }
  else
  {
    bug("bad family");
  }
}

void
vsf_sysutil_sockaddr_set_port(struct vsf_sysutil_sockaddr* p_sockptr,
                              unsigned short the_port)
{
  if (p_sockptr->u.u_sockaddr.sa_family == AF_INET)
  {
    p_sockptr->u.u_sockaddr_in.sin_port = htons(the_port);
  }
  else if (p_sockptr->u.u_sockaddr.sa_family == AF_INET6)
  {
    p_sockptr->u.u_sockaddr_in6.sin6_port = htons(the_port);
  }
  else
  {
    bug("bad family");
  }
}

int
vsf_sysutil_is_port_reserved(unsigned short the_port)
{
  if (the_port < IPPORT_RESERVED)
  {
    return 1;
  }
  return 0;
}

const char*
vsf_sysutil_inet_ntop(const struct vsf_sysutil_sockaddr* p_sockptr)
{
  const struct sockaddr* p_sockaddr = &p_sockptr->u.u_sockaddr;
  if (p_sockaddr->sa_family == AF_INET)
  {
    return inet_ntoa(p_sockptr->u.u_sockaddr_in.sin_addr);
  }
  else if (p_sockaddr->sa_family == AF_INET6)
  {
    static char inaddr_buf[64];
    const char* p_ret = inet_ntop(AF_INET6,
                                  &p_sockptr->u.u_sockaddr_in6.sin6_addr,
                                  inaddr_buf, sizeof(inaddr_buf));
    inaddr_buf[sizeof(inaddr_buf) - 1] = '\0';
    if (p_ret == NULL)
    {
      inaddr_buf[0] = '\0';
    }
    return inaddr_buf;
  }
  else
  {
    die("can only support ipv4 and ipv6 currently");
    return 0;
  }
}

const char*
vsf_sysutil_inet_ntoa(const void* p_raw_addr)
{
  return inet_ntoa(*((struct in_addr*)p_raw_addr));
}

int
vsf_sysutil_inet_aton(const char* p_text, struct vsf_sysutil_sockaddr* p_addr)
{
  struct in_addr sin_addr;
  if (p_addr->u.u_sockaddr.sa_family != AF_INET)
  {
    bug("bad family");
  }
  if (inet_aton(p_text, &sin_addr))
  {
    vsf_sysutil_memcpy(&p_addr->u.u_sockaddr_in.sin_addr,
                       &sin_addr, sizeof(p_addr->u.u_sockaddr_in.sin_addr));
    return 1;
  }
  else
  {
    return 0;
  }
}

void
vsf_sysutil_dns_resolve(struct vsf_sysutil_sockaddr** p_sockptr,
                        const char* p_name)
{
  struct hostent* hent = gethostbyname(p_name);
  if (hent == NULL)
  {
    die2("cannot resolve host:", p_name);
  }
  vsf_sysutil_sockaddr_clear(p_sockptr);
  if (hent->h_addrtype == AF_INET)
  {
    unsigned int len = hent->h_length;
    if (len > sizeof((*p_sockptr)->u.u_sockaddr_in.sin_addr))
    {
      len = sizeof((*p_sockptr)->u.u_sockaddr_in.sin_addr);
    }
    vsf_sysutil_sockaddr_alloc_ipv4(p_sockptr);
    vsf_sysutil_memcpy(&(*p_sockptr)->u.u_sockaddr_in.sin_addr,
                       hent->h_addr_list[0], len);
  }
  else if (hent->h_addrtype == AF_INET6)
  {
    unsigned int len = hent->h_length;
    if (len > sizeof((*p_sockptr)->u.u_sockaddr_in6.sin6_addr))
    {
      len = sizeof((*p_sockptr)->u.u_sockaddr_in6.sin6_addr);
    }
    vsf_sysutil_sockaddr_alloc_ipv6(p_sockptr);
    vsf_sysutil_memcpy(&(*p_sockptr)->u.u_sockaddr_in6.sin6_addr,
                       hent->h_addr_list[0], len);
  }
  else
  {
    die("gethostbyname(): neither IPv4 nor IPv6");
  }
}

struct vsf_sysutil_user*
vsf_sysutil_getpwuid(const int uid)
{
  if (uid < 0)
  {
    bug("negative uid in vsf_sysutil_getpwuid");
  }
  return (struct vsf_sysutil_user*) getpwuid((unsigned int) uid);
}

struct vsf_sysutil_user*
vsf_sysutil_getpwnam(const char* p_user)
{
  return (struct vsf_sysutil_user*) getpwnam(p_user);
}

const char*
vsf_sysutil_user_getname(const struct vsf_sysutil_user* p_user)
{
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  return p_passwd->pw_name;
}

const char*
vsf_sysutil_user_get_homedir(const struct vsf_sysutil_user* p_user)
{
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  return p_passwd->pw_dir;
}

int
vsf_sysutil_user_getuid(const struct vsf_sysutil_user* p_user)
{
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  return p_passwd->pw_uid;
}

int
vsf_sysutil_user_getgid(const struct vsf_sysutil_user* p_user)
{ 
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  return p_passwd->pw_gid;
}

struct vsf_sysutil_group*
vsf_sysutil_getgrgid(const int gid)
{
  if (gid < 0)
  {
    die("negative gid in vsf_sysutil_getgrgid");
  }
  return (struct vsf_sysutil_group*) getgrgid((unsigned int) gid);
}

const char*
vsf_sysutil_group_getname(const struct vsf_sysutil_group* p_group)
{
  const struct group* p_grp = (const struct group*) p_group;
  return p_grp->gr_name;
}

unsigned char
vsf_sysutil_get_random_byte(void)
{
  static int seeded;
  unsigned int uint_res;
  unsigned char c1, c2, c3, c4;
  if (!seeded)
  {
    struct timeval tv;
    int retval = gettimeofday(&tv, NULL);
    if (retval != 0)
    {
      die("gettimeofday");
    }
    srand((unsigned)tv.tv_usec);
    seeded = 1;
  }
  uint_res = rand();
  c1 = uint_res & 0x000000ff;
  c2 = (uint_res >> 8) & 0x000000ff;
  c3 = (uint_res >> 16) & 0x000000ff;
  c4 = (uint_res >> 24) & 0x000000ff;
  return c1 ^ c2 ^ c3 ^ c4;    
}

int
vsf_sysutil_running_as_root(void)
{
  return (getuid() == 0);
}

void
vsf_sysutil_setuid(const struct vsf_sysutil_user* p_user)
{
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  vsf_sysutil_setuid_numeric(p_passwd->pw_uid);
}

void
vsf_sysutil_setuid_numeric(int uid)
{
  int retval = setuid(uid);
  if (retval != 0)
  {
    die("setuid");
  }
}

void
vsf_sysutil_setgid(const struct vsf_sysutil_user* p_user)
{
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  vsf_sysutil_setgid_numeric(p_passwd->pw_gid);
}

void
vsf_sysutil_setgid_numeric(int gid)
{
  int retval = setgid(gid);
  if (retval != 0)
  {
    die("setgid");
  }
}

int
vsf_sysutil_geteuid(void)
{
  int retval = geteuid();
  if (retval < 0)
  {
    die("geteuid");
  }
  return retval;
}

int
vsf_sysutil_getegid(void)
{
  int retval = getegid();
  if (retval < 0)
  {
    die("getegid");
  }
  return retval;
}

void
vsf_sysutil_seteuid(const struct vsf_sysutil_user* p_user)
{
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  vsf_sysutil_seteuid_numeric(p_passwd->pw_uid);
}

void
vsf_sysutil_setegid(const struct vsf_sysutil_user* p_user)
{
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  vsf_sysutil_setegid_numeric(p_passwd->pw_gid);
}

void
vsf_sysutil_seteuid_numeric(int uid)
{
  /* setreuid() would seem to be more portable than seteuid() */
  int retval = setreuid(-1, uid);
  if (retval != 0)
  {
    die("seteuid");
  }
}

void
vsf_sysutil_setegid_numeric(int gid)
{
  /* setregid() would seem to be more portable than setegid() */
  int retval = setregid(-1, gid);
  if (retval != 0)
  {
    die("setegid");
  }
}

void
vsf_sysutil_clear_supp_groups(void)
{
  int retval = setgroups(0, NULL);
  if (retval != 0)
  {
    die("setgroups");
  }
}

void
vsf_sysutil_initgroups(const struct vsf_sysutil_user* p_user)
{
  const struct passwd* p_passwd = (const struct passwd*) p_user;
  int retval = initgroups(p_passwd->pw_name, p_passwd->pw_gid);
  if (retval != 0)
  {
    die("initgroups");
  }
}

void
vsf_sysutil_chroot(const char* p_root_path)
{
  int retval = chroot(p_root_path);
  if (retval != 0)
  {
    die("chroot");
  }
}

unsigned int
vsf_sysutil_get_umask(void)
{
  return s_current_umask;
}

void
vsf_sysutil_set_umask(unsigned int new_umask)
{
  s_current_umask = (new_umask & 0777);
  (void) umask(s_current_umask);
}

void
vsf_sysutil_make_session_leader(void)
{
  /* This makes us the leader if we are not already */
  (void) setsid();
  /* Check we're the leader */
  if (getpid() != getpgrp())
  {
    die("not session leader");
  }
}

void
vsf_sysutil_tzset(void)
{
  int retval;
  char tzbuf[sizeof("+HHMM!")];
  time_t the_time = time(NULL);
  struct tm* p_tm;
  tzset();
  p_tm = localtime(&the_time);
  if (p_tm == NULL)
  {
    die("localtime");
  }
  /* Set our timezone in the TZ environment variable to cater for the fact
   * that modern glibc does not cache /etc/localtime (which becomes inaccessible
   * when we chroot().
   */
  retval = strftime(tzbuf, sizeof(tzbuf), "%z", p_tm);
  tzbuf[sizeof(tzbuf) - 1] = '\0';
  if (retval == 5)
  {
    /* Static because putenv() does not copy the string. */
    static char envtz[sizeof("TZ=UTC-hh:mm")];
    /* Insert a colon so we have e.g. -05:00 instead of -0500 */
    tzbuf[5] = tzbuf[4];
    tzbuf[4] = tzbuf[3];
    tzbuf[3] = ':';
    /* Invert the sign - we just got the offset _from_ UTC but for TZ, we need
     * the offset _to_ UTC.
     */
    if (tzbuf[0] == '+')
    {
      tzbuf[0] = '-';
    }
    else
    {
      tzbuf[0] = '+';
    }
    snprintf(envtz, sizeof(envtz), "TZ=UTC%s", tzbuf);
    putenv(envtz);
    s_timezone = ((tzbuf[1] - '0') * 10 + (tzbuf[2] - '0')) * 60 * 60;
    s_timezone += ((tzbuf[4] - '0') * 10 + (tzbuf[5] - '0')) * 60;
    if (tzbuf[0] == '-')
    {
      s_timezone *= -1;
    }
  }
}

const char*
vsf_sysutil_get_current_date(void)
{
  static char datebuf[64];
  time_t curr_time;
  const struct tm* p_tm;
  int i = 0;
  vsf_sysutil_update_cached_time();
  curr_time = vsf_sysutil_get_cached_time_sec();
  p_tm = localtime(&curr_time);
  if (strftime(datebuf, sizeof(datebuf), "%a %b!%d %H:%M:%S %Y", p_tm) == 0)
  {
    die("strftime");
  }
  datebuf[sizeof(datebuf) - 1] = '\0';
  /* This hack is because %e in strftime() isn't so portable */
  while (datebuf[i] != '!' && datebuf[i] != '\0')
  {
    ++i;
  }
  if (datebuf[i] == '!')
  {
    datebuf[i] = ' ';
    if (datebuf[i+1] == '0')
    {
      datebuf[i+1] = ' ';
    }
  }
  return datebuf;
}

void
vsf_sysutil_update_cached_time(void)
{
  if (gettimeofday(&s_current_time, NULL) != 0)
  {
    die("gettimeofday");
  }
}

long
vsf_sysutil_get_cached_time_sec(void)
{
  return s_current_time.tv_sec;
}

long
vsf_sysutil_get_cached_time_usec(void)
{
  return s_current_time.tv_usec;
}

void
vsf_sysutil_qsort(void* p_base, unsigned int num_elem, unsigned int elem_size,
                  int (*p_compar)(const void *, const void *))
{
  qsort(p_base, num_elem, elem_size, p_compar);
}

void
vsf_sysutil_sleep(double seconds)
{
  int retval;
  int saved_errno;
  double fractional;
  time_t secs;
  struct timespec ts;
  secs = (time_t) seconds;
  fractional = seconds - (double) secs;
  ts.tv_sec = secs;
  ts.tv_nsec = (long) (fractional * (double) 1000000000);
  do
  {
    retval = nanosleep(&ts, &ts);
    saved_errno = errno;
    vsf_sysutil_check_pending_actions(kVSFSysUtilUnknown, 0, 0);
  } while (retval == -1 && saved_errno == EINTR);
}

char*
vsf_sysutil_getenv(const char* p_var)
{
  return getenv(p_var);
}

void
vsf_sysutil_openlog(void)
{
  int facility = LOG_DAEMON;
#ifdef LOG_FTP
  facility = LOG_FTP;
#endif
  openlog("vsftpd", LOG_NDELAY, facility);
}

void
vsf_sysutil_syslog(const char* p_text, int severe)
{
  int prio = LOG_INFO;
  if (severe)
  {
    prio = LOG_WARNING;
  }
  syslog(prio, "%s", p_text);
}

long
vsf_sysutil_parse_time(const char* p_text)
{
  struct tm the_time;
  unsigned int len = vsf_sysutil_strlen(p_text);
  vsf_sysutil_memclr(&the_time, sizeof(the_time));
  if (len >= 8)
  {
    char yr[5];
    char mon[3];
    char day[3];
    vsf_sysutil_strcpy(yr, p_text, 5);
    vsf_sysutil_strcpy(mon, p_text + 4, 3);
    vsf_sysutil_strcpy(day, p_text + 6, 3);
    the_time.tm_year = vsf_sysutil_atoi(yr) - 1900;
    the_time.tm_mon = vsf_sysutil_atoi(mon) - 1;
    the_time.tm_mday = vsf_sysutil_atoi(day);
  }
  if (len >= 14)
  {
    char hr[3];
    char mins[3];
    char sec[3];
    vsf_sysutil_strcpy(hr, p_text + 8, 3);
    vsf_sysutil_strcpy(mins, p_text + 10, 3);
    vsf_sysutil_strcpy(sec, p_text + 12, 3);
    the_time.tm_hour = vsf_sysutil_atoi(hr);
    the_time.tm_min = vsf_sysutil_atoi(mins);
    the_time.tm_sec = vsf_sysutil_atoi(sec);
  }
  return mktime(&the_time);
}

int
vsf_sysutil_setmodtime(const char* p_file, long the_time, int is_localtime)
{
  struct utimbuf new_times;
  if (!is_localtime)
  {
    the_time -= s_timezone;
  }
  vsf_sysutil_memclr(&new_times, sizeof(new_times));
  new_times.actime = the_time;
  new_times.modtime = the_time;
  return utime(p_file, &new_times);
}