trusts/formats.c

   1 #include <stdio.h>
   2 #include <stdint.h>
   3 #include <time.h>
   4
   5 int trusts_parsecidr(const char *host, uint32_t *ip, short *mask) {
   6   unsigned int octet1 = 0, octet2 = 0, octet3 = 0, octet4 = 0, umask = 32;
   7
   8   if(sscanf(host, "%u.%u.%u.%u/%u", &octet1, &octet2, &octet3, &octet4, &umask) != 5)
   9     if(sscanf(host, "%u.%u.%u/%u", &octet1, &octet2, &octet3, &umask) != 4)
  10       if(sscanf(host, "%u.%u/%u", &octet1, &octet2, &umask) != 3)
  11         if(sscanf(host, "%u/%u", &octet1, &umask) != 2)
  12           if(sscanf(host, "%u.%u.%u.%u", &octet1, &octet2, &octet3, &octet4) != 4)
  13             return 0;
  14
  15   if(octet1 > 255 || octet2 > 255 || octet3 > 255 || octet4 > 255 || umask > 32)
  16     return 0;
  17
  18   *ip = (octet1 << 24) | (octet2 << 16) | (octet3 << 8) | octet4;
  19   *mask = umask;
  20
  21   return 1;
  22 }
  23
  24 /* returns mask pre-anded */
  25 int trusts_str2cidr(const char *host, uint32_t *ip, uint32_t *mask) {
  26   uint32_t result;
  27   short smask;
  28
  29   if(!trusts_parsecidr(host, &result, &smask))
  30     return 0;
  31
  32   if(smask == 0) {
  33     *mask = 0;
  34   } else {
  35     *mask = 0xffffffff << (32 - smask);
  36   }
  37   *ip = result & *mask;
  38
  39   return 1;
  40 }
  41
  42 char *trusts_cidr2str(uint32_t ip, uint32_t mask) {
  43   static char buf[100];
  44   char maskbuf[10];
  45
  46   if(mask != 0) {
  47     /* count number of trailing zeros */
  48     float f = (float)(mask & -mask);
  49
  50     mask = 32 - ((*(unsigned int *)&f >> 23) - 0x7f);
  51   }
  52
  53   if(mask < 32) {
  54     snprintf(maskbuf, sizeof(maskbuf), "/%u", mask);
  55   } else {
  56     maskbuf[0] = '\0';
  57   }
  58
  59   snprintf(buf, sizeof(buf), "%u.%u.%u.%u%s", (ip >> 24) & 0xff, (ip >> 16) & 0xff, (ip >> 8) & 0xff, ip & 0xff, maskbuf);
  60
  61   return buf;
  62 }
  63
  64 char *trusts_timetostr(time_t t) {
  65   static char buf[100];
  66
  67   strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", localtime(&t));
  68
  69   return buf;
  70 }
  71