2 * Copyright (c) 2004 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 static const unsigned base = 36;
41 static const unsigned t_min = 1;
42 static const unsigned t_max = 26;
43 static const unsigned skew = 38;
44 static const unsigned damp = 700;
45 static const unsigned initial_n = 128;
46 static const unsigned initial_bias = 72;
51 return "abcdefghijklmnopqrstuvwxyz0123456789"[n];
55 adapt(unsigned delta, unsigned numpoints, int first)
63 delta += delta / numpoints;
65 while (delta > ((base - t_min) * t_max) / 2) {
66 delta /= base - t_min;
69 return k + (((base - t_min + 1) * delta) / (delta + skew));
73 * Convert an UCS4 string to a puny-coded DNS label string suitable
74 * when combined with delimiters and other labels for DNS lookup.
76 * @param in an UCS4 string to convert
77 * @param in_len the length of in.
78 * @param out the resulting puny-coded string. The string is not NUL
80 * @param out_len before processing out_len should be the length of
81 * the out variable, after processing it will be the length of the out
84 * @return returns 0 on success, an wind error code otherwise
89 wind_punycode_label_toascii(const uint32_t *in, size_t in_len,
90 char *out, size_t *out_len)
92 unsigned n = initial_n;
94 unsigned bias = initial_bias;
101 for (i = 0; i < in_len; ++i) {
105 return WIND_ERR_OVERRUN;
112 return WIND_ERR_OVERRUN;
115 /* is this string punycoded */
117 if (o + 4 >= *out_len)
118 return WIND_ERR_OVERRUN;
119 memmove(out + 4, out, o);
120 memcpy(out, "xn--", 4);
126 for (i = 0; i < in_len; ++i)
127 if(in[i] < m && in[i] >= n)
130 delta += (m - n) * (h + 1);
132 for (i = 0; i < in_len; ++i) {
135 } else if (in[i] == n) {
138 for (k = base; ; k += base) {
142 else if (k >= bias + t_max)
149 return WIND_ERR_OVERRUN;
150 out[o++] = digit(t + ((q - t) % (base - t)));
151 q = (q - t) / (base - t);
154 return WIND_ERR_OVERRUN;
157 bias = adapt(delta, h + 1, h == b);