lib/util/util_str_hex.c

   1 #include "replace.h"
   2 #include "libcli/util/ntstatus.h"
   3 #include "util_str_hex.h"
   4
   5 NTSTATUS read_hex_bytes(const char *s, uint hexchars, uint64_t *dest)
   6 {
   7         uint64_t x = 0;
   8         uint i;
   9         char c;
  10
  11         if ((hexchars & 1) || hexchars > 16) {
  12                 return NT_STATUS_INVALID_PARAMETER;
  13         }
  14
  15         for (i = 0; i < hexchars; i++) {
  16                 x <<= 4;
  17                 c = s[i];
  18                 if (c >= '0' && c <= '9') {
  19                         x += c - '0';
  20                 }
  21                 else if (c >= 'a' && c <= 'f') {
  22                         x += c - 'a' + 10;
  23                 }
  24                 else if (c >= 'A' && c <= 'F') {
  25                         x += c - 'A' + 10;
  26                 }
  27                 else {
  28                         /* BAD character (including '\0') */
  29                         return NT_STATUS_INVALID_PARAMETER;
  30                 }
  31         }
  32         *dest = x;
  33         return NT_STATUS_OK;
  34 }
  35
  36
  37 NTSTATUS parse_guid_string(const char *s,
  38                            uint32_t *time_low,
  39                            uint32_t *time_mid,
  40                            uint32_t *time_hi_and_version,
  41                            uint32_t clock_seq[2],
  42                            uint32_t node[6])
  43 {
  44         uint64_t tmp;
  45         NTSTATUS status;
  46         int i;
  47         /* "e12b56b6-0a95-11d1-adbb-00c04fd8d5cd"
  48                 |     |    |    |    |
  49                 |     |    |    |    \ node[6]
  50                 |     |    |    \_____ clock_seq[2]
  51                 |     |    \__________ time_hi_and_version
  52                 |     \_______________ time_mid
  53                 \_____________________ time_low
  54         */
  55         status = read_hex_bytes(s, 8, &tmp);
  56         if (!NT_STATUS_IS_OK(status) || s[8] != '-') {
  57                 return NT_STATUS_INVALID_PARAMETER;
  58         }
  59         *time_low = tmp;
  60         s += 9;
  61
  62         status = read_hex_bytes(s, 4, &tmp);
  63         if (!NT_STATUS_IS_OK(status) || s[4] != '-') {
  64                 return NT_STATUS_INVALID_PARAMETER;
  65         }
  66         *time_mid = tmp;
  67         s += 5;
  68
  69         status = read_hex_bytes(s, 4, &tmp);
  70         if (!NT_STATUS_IS_OK(status) || s[4] != '-') {
  71                 return NT_STATUS_INVALID_PARAMETER;
  72         }
  73         *time_hi_and_version = tmp;
  74         s += 5;
  75
  76         for (i = 0; i < 2; i++) {
  77                 status = read_hex_bytes(s, 2, &tmp);
  78                 if (!NT_STATUS_IS_OK(status)) {
  79                         return NT_STATUS_INVALID_PARAMETER;
  80                 }
  81                 clock_seq[i] = tmp;
  82                 s += 2;
  83         }
  84         if (s[0] != '-') {
  85                 return NT_STATUS_INVALID_PARAMETER;
  86         }
  87
  88         s++;
  89
  90         for (i = 0; i < 6; i++) {
  91                 status = read_hex_bytes(s, 2, &tmp);
  92                 if (!NT_STATUS_IS_OK(status)) {
  93                         return NT_STATUS_INVALID_PARAMETER;
  94                 }
  95                 node[i] = tmp;
  96                 s += 2;
  97         }
  98
  99         return NT_STATUS_OK;
 100 }