b64-cl.c

   1 #include "b64-cl.h"
   2
   3 const char b64_table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
   4
   5 u32 b64_encode (u8 *base64_hash, const u32 len, const u8 *base64_plain)
   6 {
   7         u8 *out_ptr = (u8 *) base64_hash;
   8         u8 *in_ptr  = (u8 *) base64_plain;
   9
  10         u32 i;
  11
  12         for (i = 0; i < (len - 2); i += 3)
  13         {
  14                 char out_val0 = b64_table [                            ((in_ptr[0] >> 2) & 0x3f)];
  15                 char out_val1 = b64_table [((in_ptr[0] << 4) & 0x30) | ((in_ptr[1] >> 4) & 0x0f)];
  16                 char out_val2 = b64_table [((in_ptr[1] << 2) & 0x3c) | ((in_ptr[2] >> 6) & 0x03)];
  17                 char out_val3 = b64_table [                            ((in_ptr[2] >> 0) & 0x3f)];
  18
  19                 out_ptr[0] = out_val0 & 0x7f;
  20                 out_ptr[1] = out_val1 & 0x7f;
  21                 out_ptr[2] = out_val2 & 0x7f;
  22                 out_ptr[3] = out_val3 & 0x7f;
  23
  24                 in_ptr  += 3;
  25                 out_ptr += 4;
  26         }
  27                 if (i == (len - 1)) {
  28                 char out_val0 = b64_table [                            ((in_ptr[0] >> 2) & 0x3f)];
  29                 char out_val1 = b64_table [((in_ptr[0] << 4) & 0x30)                            ];
  30
  31                 out_ptr[0] = out_val0 & 0x7f;
  32                 out_ptr[1] = out_val1 & 0x7f;
  33                 out_ptr[2] = '=';
  34                 out_ptr[3] = '=';
  35
  36                 in_ptr  += 3;
  37                 out_ptr += 4;
  38                 }
  39                 if (i == (len - 2)) {
  40                 char out_val0 = b64_table [                            ((in_ptr[0] >> 2) & 0x3f)];
  41                 char out_val1 = b64_table [((in_ptr[0] << 4) & 0x30) | ((in_ptr[1] >> 4) & 0x0f)];
  42                 char out_val2 = b64_table [((in_ptr[1] << 2) & 0x3c)                            ];
  43
  44                 out_ptr[0] = out_val0 & 0x7f;
  45                 out_ptr[1] = out_val1 & 0x7f;
  46                 out_ptr[2] = out_val2 & 0x7f;
  47                 out_ptr[3] = '=';
  48
  49                 in_ptr  += 3;
  50                 out_ptr += 4;
  51                 }
  52
  53                 return (out_ptr - base64_hash + 0);
  54 }
  55