uclient-utils.c

   1 /*
   2  * uclient - ustream based protocol client library
   3  *
   4  * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18 #include <stdint.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <ctype.h>
  22
  23 #include <libubox/md5.h>
  24 #include <libubox/utils.h>
  25
  26 #include "uclient-utils.h"
  27
  28 static const char *b64 =
  29 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  30
  31 void base64_encode(const void *inbuf, unsigned int len, void *outbuf)
  32 {
  33         unsigned char *out = outbuf;
  34         const uint8_t *in = inbuf;
  35         unsigned int i;
  36         int pad = len % 3;
  37
  38         for (i = 0; i < len - pad; i += 3) {
  39                 uint32_t in3 = (in[0] << 16) | (in[1] << 8) | in[2];
  40                 int k;
  41
  42                 for (k = 3; k >= 0; k--) {
  43                         out[k] = b64[in3 & 0x3f];
  44                         in3 >>= 6;
  45                 }
  46                 in += 3;
  47                 out += 4;
  48         }
  49
  50         if (pad) {
  51                 uint32_t in2 = in[0] << (16 - 6);
  52
  53                 out[3] = '=';
  54
  55                 if (pad > 1) {
  56                         in2 |= in[1] << (8 - 6);
  57                         out[2] = b64[in2 & 0x3f];
  58                 } else {
  59                         out[2] = '=';
  60                 }
  61
  62                 in2 >>= 6;
  63                 out[1] = b64[in2 & 0x3f];
  64                 in2 >>= 6;
  65                 out[0] = b64[in2 & 0x3f];
  66
  67                 out += 4;
  68         }
  69
  70         *out = '\0';
  71 }
  72
  73 int uclient_urldecode(const char *in, char *out, bool decode_plus)
  74 {
  75         static char dec[3];
  76         int ret = 0;
  77         char c;
  78
  79         while ((c = *(in++))) {
  80                 if (c == '%') {
  81                         if (!isxdigit(in[0]) || !isxdigit(in[1]))
  82                                 return -1;
  83
  84                         dec[0] = in[0];
  85                         dec[1] = in[1];
  86                         c = strtol(dec, NULL, 16);
  87                         in += 2;
  88                 } else if (decode_plus && c == '+') {
  89                         c = ' ';
  90                 }
  91
  92                 *(out++) = c;
  93                 ret++;
  94         }
  95
  96         *out = 0;
  97         return ret;
  98 }
  99
 100 static char hex_digit(char val)
 101 {
 102         val += val > 9 ? 'a' - 10 : '0';
 103         return val;
 104 }
 105
 106 void bin_to_hex(char *dest, const void *buf, int len)
 107 {
 108         const uint8_t *data = buf;
 109         int i;
 110
 111         for (i = 0; i < len; i++) {
 112                 *(dest++) = hex_digit(data[i] >> 4);
 113                 *(dest++) = hex_digit(data[i] & 0xf);
 114         }
 115         *dest = 0;
 116 }
 117
 118 static void http_create_hash(char *dest, const char * const * str, int n_str)
 119 {
 120         uint32_t hash[4];
 121         md5_ctx_t md5;
 122         int i;
 123
 124         md5_begin(&md5);
 125         for (i = 0; i < n_str; i++) {
 126                 if (i)
 127                         md5_hash(":", 1, &md5);
 128                 md5_hash(str[i], strlen(str[i]), &md5);
 129         }
 130         md5_end(hash, &md5);
 131         bin_to_hex(dest, &hash, sizeof(hash));
 132 }
 133
 134 void http_digest_calculate_auth_hash(char *dest, const char *user, const char *realm, const char *password)
 135 {
 136         const char *hash_str[] = {
 137                 user,
 138                 realm,
 139                 password
 140         };
 141
 142         http_create_hash(dest, hash_str, ARRAY_SIZE(hash_str));
 143 }
 144
 145 void http_digest_calculate_response(char *dest, const struct http_digest_data *data)
 146 {
 147         const char *h_a2_strings[] = {
 148                 data->method,
 149                 data->uri,
 150         };
 151         const char *resp_strings[] = {
 152                 data->auth_hash,
 153                 data->nonce,
 154                 data->nc,
 155                 data->cnonce,
 156                 data->qop,
 157                 dest, /* initialized to H(A2) first */
 158         };
 159
 160         http_create_hash(dest, h_a2_strings, ARRAY_SIZE(h_a2_strings));
 161         http_create_hash(dest, resp_strings, ARRAY_SIZE(resp_strings));
 162 }
 163
 164 char *uclient_get_url_filename(const char *url, const char *default_name)
 165 {
 166         const char *str;
 167         int len = strcspn(url, ";&");
 168
 169         while (len > 0 && url[len - 1] == '/')
 170                 len--;
 171
 172         for (str = url + len - 1; str >= url; str--) {
 173                 if (*str == '/')
 174                         break;
 175         }
 176
 177         str++;
 178         len -= str - url;
 179
 180         if (len > 0)
 181                 return strndup(str, len);
 182
 183         return strdup(default_name);
 184 }