enhanced dns packet builder to encode some rrdata

This commit is contained in:
hyung-hwan 2020-02-24 16:39:29 +00:00
parent d98397cd1f
commit 8264142dbe
2 changed files with 83 additions and 29 deletions

View File

@ -656,6 +656,9 @@ static void on_dnc_resolve(mio_svc_dnc_t* dnc, mio_dns_msg_t* reqmsg, mio_errnum
case MIO_DNS_RRT_CNAME:
printf ("^^^ GOT REPLY.... CNAME [%s] %d\n", brr->dptr, (int)brr->dlen);
goto done;
case MIO_DNS_RRT_MX:
printf ("^^^ GOT REPLY.... MX [%s] %d\n", brr->dptr, (int)brr->dlen);
goto done;
case MIO_DNS_RRT_NS:
printf ("^^^ GOT REPLY.... NS [%s] %d\n", brr->dptr, (int)brr->dlen);
goto done;
@ -955,7 +958,7 @@ for (i = 0; i < 5; i++)
mio_bcstrtoskad (mio, "[fe80::c7e2:bd6e:1209:ac1b%eno1]:1153", &servaddr);
dnc = mio_svc_dnc_start (mio, &servaddr, MIO_NULL, &send_tmout, &reply_tmout, 2); /* option - send to all, send one by one */
#if 0
#if 1
{
mio_dns_bqr_t qrs[] =
{
@ -969,7 +972,9 @@ for (i = 0; i < 5; i++)
{
{ MIO_DNS_RR_PART_ANSWER, "code.miflux.com", MIO_DNS_RRT_A, MIO_DNS_RRC_IN, 86400, 0, MIO_NULL },
{ MIO_DNS_RR_PART_ANSWER, "code.miflux.com", MIO_DNS_RRT_AAAA, MIO_DNS_RRC_IN, 86400, 0, MIO_NULL },
{ MIO_DNS_RR_PART_AUTHORITY, "dns.miflux.com", MIO_DNS_RRT_NS, MIO_DNS_RRC_IN, 86400, 0, MIO_NULL }//,
{ MIO_DNS_RR_PART_ANSWER, "miflux.com", MIO_DNS_RRT_NS, MIO_DNS_RRC_IN, 86400, 0, "ns1.miflux.com" },
{ MIO_DNS_RR_PART_ANSWER, "miflux.com", MIO_DNS_RRT_NS, MIO_DNS_RRC_IN, 86400, 0, "ns2.miflux.com" }, //,
//{ MIO_DNS_RR_PART_AUTHORITY, "miflux.com", MIO_DNS_RRT_SOA, MIO_DNS_RRC_IN, 86400, 0, "ns2.miflux.com" }, //,
//{ MIO_DNS_RR_PART_ANSERT, "www.miflux.com", MIO_DNS_RRT_CNAME, MIO_DNS_RRC_IN, 60, 15, "code.miflux.com" }
};

View File

@ -31,10 +31,9 @@
#define DN_AT_END(ptr) (ptr[0] == '\0' || (ptr[0] == '.' && ptr[1] == '\0'))
static mio_oow_t to_dn (const mio_bch_t* str, mio_uint8_t* buf, mio_oow_t bufsz)
static mio_oow_t to_dn (const mio_bch_t* str, mio_uint8_t* buf)
{
mio_uint8_t* bp = buf, * be = buf + bufsz;
mio_uint8_t* bp = buf;
/*MIO_ASSERT (MIO_SIZEOF(mio_uint8_t) == MIO_SIZEOF(mio_bch_t));*/
if (str && !DN_AT_END(str))
@ -46,29 +45,62 @@ static mio_oow_t to_dn (const mio_bch_t* str, mio_uint8_t* buf, mio_oow_t bufsz)
do
{
if (bp < be) lp = bp++;
else lp = MIO_NULL;
lp = bp++;
seg = ++cur;
while (*cur != '\0' && *cur != '.')
{
if (bp < be) *bp++ = *cur;
*bp++ = *cur;
cur++;
}
len = cur - seg;
if (len <= 0 || len > 63) return 0;
if (lp) *lp = (mio_uint8_t)len;
*lp = (mio_uint8_t)len;
}
while (!DN_AT_END(cur));
}
if (bp < be) *bp++ = 0;
*bp++ = 0;
/* the length includes the terminating zero. */
return bp - buf;
}
static mio_oow_t to_dn_capa (const mio_bch_t* str)
{
mio_oow_t capa;
/*MIO_ASSERT (MIO_SIZEOF(mio_uint8_t) == MIO_SIZEOF(mio_bch_t));*/
if (str && !DN_AT_END(str))
{
mio_oow_t len;
const mio_bch_t* seg;
const mio_bch_t* cur = str - 1;
do
{
capa++;
seg = ++cur;
while (*cur != '\0' && *cur != '.')
{
capa++;
cur++;
}
len = cur - seg;
if (len <= 0 || len > 63) return 0;
}
while (!DN_AT_END(cur));
}
capa++;
/* the length includes the terminating zero. */
return capa;
}
static mio_oow_t dn_length (mio_uint8_t* ptr, mio_oow_t len)
{
mio_uint8_t* curptr;
@ -261,6 +293,7 @@ static int parse_answer_rr (mio_t* mio, mio_dns_rr_part_t rr_part, mio_oow_t pos
goto verbatim;
case MIO_DNS_RRT_CNAME:
case MIO_DNS_RRT_MX:
case MIO_DNS_RRT_NS:
case MIO_DNS_RRT_PTR:
{
@ -432,33 +465,38 @@ void mio_dns_free_packet_info (mio_t* mio, mio_dns_pkt_info_t* pi)
/* ----------------------------------------------------------------------- */
static mio_oow_t encode_rrdata_in_dns_msg (mio_t* mio, const mio_dns_brr_t* rr, mio_dns_rrtr_t* rrtr)
static mio_oow_t encode_rrdata_in_dns_msg (mio_t* mio, const mio_dns_brr_t* rr, void* dptr)
{
mio_oow_t xlen;
switch (rr->rrtype)
{
case MIO_DNS_RRT_A:
xlen = rr->dlen;
break;
case MIO_DNS_RRT_AAAA:
xlen = rr->dlen;
break;
/*
case MIO_DNS_RRT_WKS:
break; */
case MIO_DNS_RRT_MX:
/* preference, exchange */
break;
case MIO_DNS_RRT_CNAME:
/*case MIO_DNS_RRT_MB:
case MIO_DNS_RRT_MD:
case MIO_DNS_RRT_MF:
case MIO_DNS_RRT_MG:
case MIO_DNS_RRT_MR:*/
case MIO_DNS_RRT_MX:
case MIO_DNS_RRT_NS:
case MIO_DNS_RRT_PTR:
/* just a normal domain name */
/* TODO: take a null-terminated string and encode it using to_dn() */
if (dptr)
xlen = to_dn(rr->dptr, dptr);
else
xlen = to_dn_capa(rr->dptr);
if (xlen <= 0)
break;
#if 0
@ -471,21 +509,25 @@ static mio_oow_t encode_rrdata_in_dns_msg (mio_t* mio, const mio_dns_brr_t* rr,
case MIO_DNS_RRT_MINFO:
/* rmailbx, emailbx */
#endif
xlen = rr->dlen;
break;
case MIO_DNS_RRT_SOA:
/* soa */
xlen = rr->dlen;
break;
case MIO_DNS_RRT_TXT:
case MIO_DNS_RRT_NULL:
default:
/* TODO: custom transformator? */
rrtr->dlen = mio_hton16(rr->dlen);
if (rr->dlen > 0) MIO_MEMCPY (rrtr + 1, rr->dptr, rr->dlen);
if (rr->dlen > 0) MIO_MEMCPY (dptr, rr->dptr, rr->dlen);
xlen = rr->dlen;
break;
}
return rr->dlen;
if (MIO_UNLIKELY(xlen > MIO_TYPE_MAX(mio_uint16_t))) return 0;
return xlen;
}
mio_dns_msg_t* mio_dns_make_msg (mio_t* mio, mio_dns_bhdr_t* bhdr, mio_dns_bqr_t* qr, mio_oow_t qr_count, mio_dns_brr_t* rr, mio_oow_t rr_count, mio_dns_bedns_t* edns, mio_oow_t xtnsize)
@ -503,15 +545,20 @@ mio_dns_msg_t* mio_dns_make_msg (mio_t* mio, mio_dns_bhdr_t* bhdr, mio_dns_bqr_t
for (i = 0; i < qr_count; i++)
{
/* <length>segmnet<length>segment<zero>.
* if the input has the ending period(e.g. mio.lib.), the dn length is namelen + 1.
* if the input doesn't have the ending period(e.g. mio.lib) . the dn length is namelen + 2. */
pktlen += mio_count_bcstr(qr[i].qname) + 2 + MIO_SIZEOF(*qrtr);
pktlen += to_dn_capa(qr[i].qname) + MIO_SIZEOF(*qrtr);
}
for (i = 0; i < rr_count; i++)
{
pktlen += mio_count_bcstr(rr[i].rrname) + 2 + MIO_SIZEOF(*rrtr) + rr[i].dlen;
mio_oow_t rrdata_len;
rrdata_len = encode_rrdata_in_dns_msg(mio, &rr[i], MIO_NULL);
if (MIO_UNLIKELY(rrdata_len <= 0))
{
/* invalid rrdata */
mio_seterrnum (mio, MIO_EINVAL);
return MIO_NULL;
}
pktlen += to_dn_capa(rr[i].rrname) + MIO_SIZEOF(*rrtr) + rrdata_len;
}
edns_dlen = 0;
@ -560,7 +607,7 @@ mio_dns_msg_t* mio_dns_make_msg (mio_t* mio, mio_dns_bhdr_t* bhdr, mio_dns_bqr_t
for (i = 0; i < qr_count; i++)
{
/* dnlen includes the ending <zero> */
dnlen = to_dn(qr[i].qname, dn, mio_count_bcstr(qr[i].qname) + 2);
dnlen = to_dn(qr[i].qname, dn);
if (dnlen <= 0)
{
mio_dns_free_msg (mio, msg);
@ -581,9 +628,9 @@ mio_dns_msg_t* mio_dns_make_msg (mio_t* mio, mio_dns_bhdr_t* bhdr, mio_dns_bqr_t
{
if (rr[i].part == rr_sect)
{
mio_oow_t rdata_len;
mio_oow_t rrdata_len;
dnlen = to_dn(rr[i].rrname, dn, mio_count_bcstr(rr[i].rrname) + 2);
dnlen = to_dn(rr[i].rrname, dn);
if (dnlen <= 0)
{
mio_dns_free_msg (mio, msg);
@ -596,8 +643,10 @@ mio_dns_msg_t* mio_dns_make_msg (mio_t* mio, mio_dns_bhdr_t* bhdr, mio_dns_bqr_t
rrtr->rrclass = mio_hton16(rr[i].rrclass);
rrtr->ttl = mio_hton32(rr[i].ttl);
rdata_len = encode_rrdata_in_dns_msg(mio, &rr[i], rrtr);
dn = (mio_uint8_t*)(rrtr + 1) + rdata_len;
rrdata_len = encode_rrdata_in_dns_msg(mio, &rr[i], rrtr + 1);
MIO_ASSERT (mio, rrdata_len > 0);
rrtr->dlen = mio_hton16(rrdata_len);
dn = (mio_uint8_t*)(rrtr + 1) + rrdata_len;
match_count++;
}