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         u32 out_len;
  10
  11         u32 i;
  12
  13                 out_len = 0;
  14         for (i = 0; i < (len - 2); i += 3)
  15         {
  16                 char out_val0 = b64_table [                            ((in_ptr[0] >> 2) & 0x3f)];
  17                 char out_val1 = b64_table [((in_ptr[0] << 4) & 0x30) | ((in_ptr[1] >> 4) & 0x0f)];
  18                 char out_val2 = b64_table [((in_ptr[1] << 2) & 0x3c) | ((in_ptr[2] >> 6) & 0x03)];
  19                 char out_val3 = b64_table [                            ((in_ptr[2] >> 0) & 0x3f)];
  20
  21                 out_ptr[0] = out_val0 & 0x7f;
  22                 out_ptr[1] = out_val1 & 0x7f;
  23                 out_ptr[2] = out_val2 & 0x7f;
  24                 out_ptr[3] = out_val3 & 0x7f;
  25
  26                 in_ptr  += 3;
  27                 out_ptr += 4;
  28                 out_len += 4;
  29         }
  30                 if (i == (len - 1)) {
  31                 char out_val0 = b64_table [                            ((in_ptr[0] >> 2) & 0x3f)];
  32                 char out_val1 = b64_table [((in_ptr[0] << 4) & 0x30)                            ];
  33
  34                 out_ptr[0] = out_val0 & 0x7f;
  35                 out_ptr[1] = out_val1 & 0x7f;
  36                 out_ptr[2] = '=';
  37                 out_ptr[3] = '=';
  38
  39                 in_ptr  += 3;
  40                 out_ptr += 4;
  41                 out_len += 4;
  42                 }
  43                 if (i == (len - 2)) {
  44                 char out_val0 = b64_table [                            ((in_ptr[0] >> 2) & 0x3f)];
  45                 char out_val1 = b64_table [((in_ptr[0] << 4) & 0x30) | ((in_ptr[1] >> 4) & 0x0f)];
  46                 char out_val2 = b64_table [((in_ptr[1] << 2) & 0x3c)                            ];
  47
  48                 out_ptr[0] = out_val0 & 0x7f;
  49                 out_ptr[1] = out_val1 & 0x7f;
  50                 out_ptr[2] = out_val2 & 0x7f;
  51                 out_ptr[3] = '=';
  52
  53                 in_ptr  += 3;
  54                 out_ptr += 4;
  55                 out_len += 4;
  56                 }
  57
  58                 return out_len;
  59 }
  60