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/*
* Part of DNS zone file validator `validns`.
*
* Copyright 2011-2014 Anton Berezin <tobez@tobez.org>
* Modified BSD license.
* (See LICENSE file in the distribution.)
*
*/
#include <sys/types.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "common.h"
#include "textparse.h"
#include "mempool.h"
#include "carp.h"
#include "rr.h"
/* XXX
* We need to add the following spf-specific policy checks:
* - record not too long (DNS name + length of SPF+TXT < 450) - rfc4408, 3.1.4
* - record should match /^v=spf1( |$)/ - rfc4408, 4.5
* - maybe check for other syntax features
* - there should be an identical TXT record - rfc4408, 3.1.1
* - there should only be one SPF per DNS name - rfc4408, 4.5
*/
static struct rr *spf_parse(char *name, long ttl, int type, char *s)
{
struct rr_spf *rr;
struct binary_data spf[20];
int i;
i = 0;
while (*s) {
if (i >= 20)
return bitch("program limit: too many SPF text segments");
spf[i] = extract_text(&s, "SPF text segment");
if (spf[i].length < 0)
return NULL;
if (spf[i].length > 255)
return bitch("SPF segment too long");
i++;
}
if (i == 0)
return bitch("empty text record");
rr = getmem(sizeof(*rr) + sizeof(struct binary_data) * (i-1));
rr->count = i;
for (i = 0; i < rr->count; i++) {
rr->spf[i] = spf[i];
}
return store_record(type, name, ttl, rr);
}
static char* spf_human(struct rr *rrv)
{
RRCAST(spf);
char ss[1024];
int i;
char *s = ss;
int l;
for (i = 0; i < rr->count; i++) {
l = snprintf(s, 1024-(s-ss), "\"%s\" ", rr->spf[i].data);
s += l;
}
return quickstrdup_temp(ss);
}
static struct binary_data spf_wirerdata(struct rr *rrv)
{
RRCAST(spf);
struct binary_data r, t;
int i;
r = bad_binary_data();
t.length = 0;
t.data = NULL;
for (i = 0; i < rr->count; i++) {
r = compose_binary_data("db", 1, t, rr->spf[i]);
t = r;
}
return r;
}
struct rr_methods spf_methods = { spf_parse, spf_human, spf_wirerdata, NULL, NULL };
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