glibc/resolv/ns_name_pton.c

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/* Convert a DNS domain name from presentation to wire format.
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1996,1999 by Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <arpa/nameser.h>
#include <errno.h>
#include <shlib-compat.h>
/* Converts an ASCII string into an encoded domain name as per
RFC1035. Returns -1 if it fails, 1 if string was fully qualified,
0 is string was not fully qualified. Enforces label and domain
length limits. */
int
___ns_name_pton (const char *src, unsigned char *dst, size_t dstsiz)
{
unsigned char *label, *bp, *eom;
int c, n, escaped;
escaped = 0;
bp = dst;
eom = dst + dstsiz;
label = bp++;
while ((c = *src++) != 0)
{
if (escaped)
{
if ('0' <= c && c <= '9')
{
n = (c - '0') * 100;
if ((c = *src++) == 0 || c < '0' || c > '9')
{
__set_errno (EMSGSIZE);
return -1;
}
n += (c - '0') * 10;
if ((c = *src++) == 0 || c < '0' || c > '9')
{
__set_errno (EMSGSIZE);
return -1;
}
n += c - '0';
if (n > 255)
{
__set_errno (EMSGSIZE);
return -1;
}
c = n;
}
escaped = 0;
}
else if (c == '\\')
{
escaped = 1;
continue;
}
else if (c == '.')
{
c = (bp - label - 1);
if ((c & NS_CMPRSFLGS) != 0) /* Label too big. */
{
__set_errno (EMSGSIZE);
return -1;
}
if (label >= eom)
{
__set_errno (EMSGSIZE);
return -1;
}
*label = c;
/* Fully qualified ? */
if (*src == '\0')
{
if (c != 0)
{
if (bp >= eom)
{
__set_errno (EMSGSIZE);
return -1;
}
*bp++ = '\0';
}
if ((bp - dst) > MAXCDNAME)
{
__set_errno (EMSGSIZE);
return -1;
}
return 1;
}
if (c == 0 || *src == '.')
{
__set_errno (EMSGSIZE);
return -1;
}
label = bp++;
continue;
}
if (bp >= eom)
{
__set_errno (EMSGSIZE);
return -1;
}
*bp++ = (unsigned char) c;
}
if (escaped) /* Trailing backslash. */
{
__set_errno (EMSGSIZE);
return -1;
}
c = (bp - label - 1);
if ((c & NS_CMPRSFLGS) != 0) /* Label too big. */
{
__set_errno (EMSGSIZE);
return -1;
}
if (label >= eom)
{
__set_errno (EMSGSIZE);
return -1;
}
*label = c;
if (c != 0)
{
if (bp >= eom)
{
__set_errno (EMSGSIZE);
return -1;
}
*bp++ = 0;
}
if ((bp - dst) > MAXCDNAME) /* src too big. */
{
__set_errno (EMSGSIZE);
return -1;
}
return 0;
}
versioned_symbol (libc, ___ns_name_pton, ns_name_pton, GLIBC_2_34);
versioned_symbol (libc, ___ns_name_pton, __ns_name_pton, GLIBC_PRIVATE);
libc_hidden_ver (___ns_name_pton, __ns_name_pton)
#if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_9, GLIBC_2_34)
compat_symbol (libresolv, ___ns_name_pton, ns_name_pton, GLIBC_2_9);
#endif