Remove support for DNS Extended Label Types.

The support was only partial, and the whole concept is
now deprecated in the standards.
This commit is contained in:
Simon Kelley
2015-05-15 20:43:48 +01:00
parent 5d07d77e75
commit 06568c6636

View File

@@ -77,53 +77,7 @@ int extract_name(struct dns_header *header, size_t plen, unsigned char **pp,
p = l + (unsigned char *)header;
}
else if (label_type == 0x80)
return 0; /* reserved */
else if (label_type == 0x40)
{ /* ELT */
unsigned int count, digs;
if ((l & 0x3f) != 1)
return 0; /* we only understand bitstrings */
if (!isExtract)
return 0; /* Cannot compare bitsrings */
count = *p++;
if (count == 0)
count = 256;
digs = ((count-1)>>2)+1;
/* output is \[x<hex>/siz]. which is digs+7/8/9 chars */
namelen += digs+7;
if (count > 9)
namelen++;
if (count > 99)
namelen++;
if (namelen+1 >= MAXDNAME)
return 0;
if (!CHECK_LEN(header, p, plen, (count-1)>>3))
return 0;
*cp++ = '\\';
*cp++ = '[';
*cp++ = 'x';
for (j=0; j<digs; j++)
{
unsigned int dig;
if (j%2 == 0)
dig = *p >> 4;
else
dig = *p++ & 0x0f;
*cp++ = dig < 10 ? dig + '0' : dig + 'A' - 10;
}
cp += sprintf((char *)cp, "/%d]", count);
/* do this here to overwrite the zero char from sprintf */
*cp++ = '.';
}
else
else if (label_type == 0x00)
{ /* label_type = 0 -> label. */
namelen += l + 1; /* include period */
if (namelen >= MAXDNAME)
@@ -176,12 +130,14 @@ int extract_name(struct dns_header *header, size_t plen, unsigned char **pp,
retvalue = 2;
}
}
if (isExtract)
*cp++ = '.';
else if (*cp != 0 && *cp++ != '.')
retvalue = 2;
}
else
return 0; /* label types 0x40 and 0x80 not supported */
}
}