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#include "stralloc.h"
#include "case.h"
#include "byte.h"
#include "str.h"
#include "dns.h"
static int doit(stralloc *work,const char *rule)
{
char ch;
unsigned int colon;
unsigned int prefixlen;
ch = *rule++;
if ((ch != '?') && (ch != '=') && (ch != '*') && (ch != '-')) return 1;
colon = str_chr(rule,':');
if (!rule[colon]) return 1;
if (work->len < colon) return 1;
prefixlen = work->len - colon;
if ((ch == '=') && prefixlen) return 1;
if (case_diffb(rule,colon,work->s + prefixlen)) return 1;
if (ch == '?') {
if (byte_chr(work->s,prefixlen,'.') < prefixlen) return 1;
if (byte_chr(work->s,prefixlen,'[') < prefixlen) return 1;
if (byte_chr(work->s,prefixlen,']') < prefixlen) return 1;
}
work->len = prefixlen;
if (ch == '-') work->len = 0;
return stralloc_cats(work,rule + colon + 1);
}
int dns_ip4_qualify_rules(stralloc *out,stralloc *fqdn,const stralloc *in,const stralloc *rules)
{
unsigned int i;
unsigned int j;
unsigned int plus;
unsigned int fqdnlen;
if (!stralloc_copy(fqdn,in)) return -1;
for (j = i = 0;j < rules->len;++j)
if (!rules->s[j]) {
if (!doit(fqdn,rules->s + i)) return -1;
i = j + 1;
}
fqdnlen = fqdn->len;
plus = byte_chr(fqdn->s,fqdnlen,'+');
if (plus >= fqdnlen)
return dns_ip4(out,fqdn);
i = plus + 1;
for (;;) {
j = byte_chr(fqdn->s + i,fqdnlen - i,'+');
byte_copy(fqdn->s + plus,j,fqdn->s + i);
fqdn->len = plus + j;
if (dns_ip4(out,fqdn) == -1) return -1;
if (out->len) return 0;
i += j;
if (i >= fqdnlen) return 0;
++i;
}
}
int dns_ip4_qualify(stralloc *out,stralloc *fqdn,const stralloc *in)
{
static stralloc rules;
if (dns_resolvconfrewrite(&rules) == -1) return -1;
return dns_ip4_qualify_rules(out,fqdn,in,&rules);
}
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