uclient-utils.c

   1 #include <stdint.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <ctype.h>
   5
   6 #include <libubox/md5.h>
   7 #include <libubox/utils.h>
   8
   9 #include "uclient-utils.h"
  10
  11 static const char *b64 =
  12 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  13
  14 void base64_encode(const void *inbuf, unsigned int len, void *outbuf)
  15 {
  16         unsigned char *out = outbuf;
  17         const uint8_t *in = inbuf;
  18         unsigned int i;
  19         int pad = len % 3;
  20
  21         for (i = 0; i < len - pad; i += 3) {
  22                 uint32_t in3 = (in[0] << 16) | (in[1] << 8) | in[2];
  23                 int k;
  24
  25                 for (k = 3; k >= 0; k--) {
  26                         out[k] = b64[in3 & 0x3f];
  27                         in3 >>= 6;
  28                 }
  29                 in += 3;
  30                 out += 4;
  31         }
  32
  33         if (pad) {
  34                 uint32_t in2 = in[0] << (16 - 6);
  35
  36                 out[3] = '=';
  37
  38                 if (pad > 1) {
  39                         in2 |= in[1] << (8 - 6);
  40                         out[2] = b64[in2 & 0x3f];
  41                 } else {
  42                         out[2] = '=';
  43                 }
  44
  45                 in2 >>= 6;
  46                 out[1] = b64[in2 & 0x3f];
  47                 in2 >>= 6;
  48                 out[0] = b64[in2 & 0x3f];
  49
  50                 out += 4;
  51         }
  52
  53         *out = '\0';
  54 }
  55
  56 int uclient_urldecode(const char *in, char *out, bool decode_plus)
  57 {
  58         static char dec[3];
  59         int ret = 0;
  60         char c;
  61
  62         while ((c = *(in++))) {
  63                 if (c == '%') {
  64                         if (!isxdigit(in[0]) || !isxdigit(in[1]))
  65                                 return -1;
  66
  67                         dec[0] = in[0];
  68                         dec[1] = in[1];
  69                         c = strtol(dec, NULL, 16);
  70                         in += 2;
  71                 } else if (decode_plus && c == '+') {
  72                         c = ' ';
  73                 }
  74
  75                 *(out++) = c;
  76                 ret++;
  77         }
  78
  79         *out = 0;
  80         return ret;
  81 }
  82
  83 static char hex_digit(char val)
  84 {
  85         val += val > 9 ? 'a' - 10 : '0';
  86         return val;
  87 }
  88
  89 void bin_to_hex(char *dest, const void *buf, int len)
  90 {
  91         const uint8_t *data = buf;
  92         int i;
  93
  94         for (i = 0; i < len; i++) {
  95                 *(dest++) = hex_digit(data[i] >> 4);
  96                 *(dest++) = hex_digit(data[i] & 0xf);
  97         }
  98         *dest = 0;
  99 }
 100
 101 static void http_create_hash(char *dest, const char * const * str, int n_str)
 102 {
 103         uint32_t hash[4];
 104         md5_ctx_t md5;
 105         int i;
 106
 107         md5_begin(&md5);
 108         for (i = 0; i < n_str; i++) {
 109                 if (i)
 110                         md5_hash(":", 1, &md5);
 111                 md5_hash(str[i], strlen(str[i]), &md5);
 112         }
 113         md5_end(hash, &md5);
 114         bin_to_hex(dest, &hash, sizeof(hash));
 115 }
 116
 117 void http_digest_calculate_auth_hash(char *dest, const char *user, const char *realm, const char *password)
 118 {
 119         const char *hash_str[] = {
 120                 user,
 121                 realm,
 122                 password
 123         };
 124
 125         http_create_hash(dest, hash_str, ARRAY_SIZE(hash_str));
 126 }
 127
 128 void http_digest_calculate_response(char *dest, const struct http_digest_data *data)
 129 {
 130         const char *h_a2_strings[] = {
 131                 data->method,
 132                 data->uri,
 133         };
 134         const char *resp_strings[] = {
 135                 data->auth_hash,
 136                 data->nonce,
 137                 data->nc,
 138                 data->cnonce,
 139                 data->qop,
 140                 dest, /* initialized to H(A2) first */
 141         };
 142
 143         http_create_hash(dest, h_a2_strings, ARRAY_SIZE(h_a2_strings));
 144         http_create_hash(dest, resp_strings, ARRAY_SIZE(resp_strings));
 145 }