uclient-utils.c

   1 #include <stdint.h>
   2 #include <stdlib.h>
   3 #include <ctype.h>
   4
   5 #include "uclient-utils.h"
   6
   7 static const char *b64 =
   8 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
   9
  10 void base64_encode(const void *inbuf, unsigned int len, void *outbuf)
  11 {
  12         unsigned char *out = outbuf;
  13         const uint8_t *in = inbuf;
  14         unsigned int i;
  15         int pad = len % 3;
  16
  17         for (i = 0; i < len - pad; i += 3) {
  18                 uint32_t in3 = (in[0] << 16) | (in[1] << 8) | in[2];
  19                 int k;
  20
  21                 for (k = 3; k >= 0; k--) {
  22                         out[k] = b64[in3 & 0x3f];
  23                         in3 >>= 6;
  24                 }
  25                 in += 3;
  26                 out += 4;
  27         }
  28
  29         if (pad) {
  30                 uint32_t in2 = in[0] << (16 - 6);
  31
  32                 out[3] = '=';
  33
  34                 if (pad > 1) {
  35                         in2 |= in[1] << (8 - 6);
  36                         out[2] = b64[in2 & 0x3f];
  37                 } else {
  38                         out[2] = '=';
  39                 }
  40
  41                 in2 >>= 6;
  42                 out[1] = b64[in2 & 0x3f];
  43                 in2 >>= 6;
  44                 out[0] = b64[in2 & 0x3f];
  45
  46                 out += 4;
  47         }
  48
  49         *out = '\0';
  50 }
  51
  52 int uclient_urldecode(const char *in, char *out, bool decode_plus)
  53 {
  54         static char dec[3];
  55         int ret = 0;
  56         char c;
  57
  58         while ((c = *(in++))) {
  59                 if (c == '%') {
  60                         if (!isxdigit(in[0]) || !isxdigit(in[1]))
  61                                 return -1;
  62
  63                         dec[0] = in[0];
  64                         dec[1] = in[1];
  65                         c = strtol(dec, NULL, 16);
  66                         in += 2;
  67                 } else if (decode_plus && c == '+') {
  68                         c = ' ';
  69                 }
  70
  71                 *(out++) = c;
  72                 ret++;
  73         }
  74
  75         *out = 0;
  76         return ret;
  77 }