int
ares_parse_soa_reply(const unsigned char *abuf, int alen,
struct ares_soa_reply **soa_out)
{
const unsigned char *aptr;
long len;
char *qname = NULL, *rr_name = NULL;
struct ares_soa_reply *soa = NULL;
int qdcount, ancount;
int status;
if (alen < HFIXEDSZ)
return ARES_EBADRESP;
/* parse message header */
qdcount = DNS_HEADER_QDCOUNT(abuf);
ancount = DNS_HEADER_ANCOUNT(abuf);
if (qdcount != 1 || ancount != 1)
return ARES_EBADRESP;
aptr = abuf + HFIXEDSZ;
/* query name */
status = ares__expand_name_for_response(aptr, abuf, alen, &qname, &len);
if (status != ARES_SUCCESS)
goto failed_stat;
aptr += len;
/* skip qtype & qclass */
if (aptr + QFIXEDSZ > abuf + alen)
goto failed;
aptr += QFIXEDSZ;
/* rr_name */
status = ares__expand_name_for_response(aptr, abuf, alen, &rr_name, &len);
if (status != ARES_SUCCESS)
goto failed_stat;
aptr += len;
/* skip rr_type, rr_class, rr_ttl, rr_rdlen */
if (aptr + RRFIXEDSZ > abuf + alen)
goto failed;
aptr += RRFIXEDSZ;
/* allocate result struct */
soa = ares_malloc_data(ARES_DATATYPE_SOA_REPLY);
if (!soa)
{
status = ARES_ENOMEM;
goto failed_stat;
}
/* nsname */
status = ares__expand_name_for_response(aptr, abuf, alen, &soa->nsname, &len);
if (status != ARES_SUCCESS)
goto failed_stat;
aptr += len;
/* hostmaster */
status = ares__expand_name_for_response(aptr, abuf, alen, &soa->hostmaster, &len);
if (status != ARES_SUCCESS)
goto failed_stat;
aptr += len;
/* integer fields */
if (aptr + 5 * 4 > abuf + alen)
goto failed;
soa->serial = DNS__32BIT(aptr + 0 * 4);
soa->refresh = DNS__32BIT(aptr + 1 * 4);
soa->retry = DNS__32BIT(aptr + 2 * 4);
soa->expire = DNS__32BIT(aptr + 3 * 4);
soa->minttl = DNS__32BIT(aptr + 4 * 4);
free(qname);
free(rr_name);
*soa_out = soa;
return ARES_SUCCESS;
failed:
status = ARES_EBADRESP;
failed_stat:
ares_free_data(soa);
if (qname)
free(qname);
if (rr_name)
free(rr_name);
return status;
}
static const unsigned char *display_rr(const unsigned char *aptr,
const unsigned char *abuf, int alen)
{
const unsigned char *p;
int type, dnsclass, ttl, dlen, status;
long len;
char addr[46];
union {
unsigned char * as_uchar;
char * as_char;
} name;
/* Parse the RR name. */
status = ares_expand_name(aptr, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
aptr += len;
/* Make sure there is enough data after the RR name for the fixed
* part of the RR.
*/
if (aptr + RRFIXEDSZ > abuf + alen)
{
ares_free_string(name.as_char);
return NULL;
}
/* Parse the fixed part of the RR, and advance to the RR data
* field. */
type = DNS_RR_TYPE(aptr);
dnsclass = DNS_RR_CLASS(aptr);
ttl = DNS_RR_TTL(aptr);
dlen = DNS_RR_LEN(aptr);
aptr += RRFIXEDSZ;
if (aptr + dlen > abuf + alen)
{
ares_free_string(name.as_char);
return NULL;
}
/* Display the RR name, class, and type. */
printf("\t%-15s.\t%d", name.as_char, ttl);
if (dnsclass != C_IN)
printf("\t%s", class_name(dnsclass));
printf("\t%s", type_name(type));
ares_free_string(name.as_char);
/* Display the RR data. Don't touch aptr. */
switch (type)
{
case T_CNAME:
case T_MB:
case T_MD:
case T_MF:
case T_MG:
case T_MR:
case T_NS:
case T_PTR:
/* For these types, the RR data is just a domain name. */
status = ares_expand_name(aptr, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s.", name.as_char);
ares_free_string(name.as_char);
break;
case T_HINFO:
/* The RR data is two length-counted character strings. */
p = aptr;
len = *p;
if (p + len + 1 > aptr + dlen)
return NULL;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s", name.as_char);
ares_free_string(name.as_char);
p += len;
len = *p;
if (p + len + 1 > aptr + dlen)
return NULL;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s", name.as_char);
ares_free_string(name.as_char);
break;
case T_MINFO:
/* The RR data is two domain names. */
p = aptr;
status = ares_expand_name(p, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s.", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_name(p, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s.", name.as_char);
ares_free_string(name.as_char);
break;
case T_MX:
/* The RR data is two bytes giving a preference ordering, and
* then a domain name.
*/
if (dlen < 2)
return NULL;
printf("\t%d", DNS__16BIT(aptr));
status = ares_expand_name(aptr + 2, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s.", name.as_char);
ares_free_string(name.as_char);
break;
case T_SOA:
/* The RR data is two domain names and then five four-byte
* numbers giving the serial number and some timeouts.
*/
p = aptr;
status = ares_expand_name(p, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s.\n", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_name(p, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s.\n", name.as_char);
ares_free_string(name.as_char);
p += len;
if (p + 20 > aptr + dlen)
return NULL;
printf("\t\t\t\t\t\t( %lu %lu %lu %lu %lu )",
(unsigned long)DNS__32BIT(p), (unsigned long)DNS__32BIT(p+4),
(unsigned long)DNS__32BIT(p+8), (unsigned long)DNS__32BIT(p+12),
(unsigned long)DNS__32BIT(p+16));
break;
case T_TXT:
/* The RR data is one or more length-counted character
* strings. */
p = aptr;
while (p < aptr + dlen)
{
len = *p;
if (p + len + 1 > aptr + dlen)
return NULL;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s", name.as_char);
ares_free_string(name.as_char);
p += len;
}
break;
case T_A:
/* The RR data is a four-byte Internet address. */
if (dlen != 4)
return NULL;
printf("\t%s", ares_inet_ntop(AF_INET,aptr,addr,sizeof(addr)));
break;
case T_AAAA:
/* The RR data is a 16-byte IPv6 address. */
if (dlen != 16)
return NULL;
printf("\t%s", ares_inet_ntop(AF_INET6,aptr,addr,sizeof(addr)));
break;
case T_WKS:
/* Not implemented yet */
break;
case T_SRV:
/* The RR data is three two-byte numbers representing the
* priority, weight, and port, followed by a domain name.
*/
printf("\t%d", DNS__16BIT(aptr));
printf(" %d", DNS__16BIT(aptr + 2));
printf(" %d", DNS__16BIT(aptr + 4));
status = ares_expand_name(aptr + 6, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s.", name.as_char);
ares_free_string(name.as_char);
break;
case T_NAPTR:
printf("\t%d", DNS__16BIT(aptr)); /* order */
printf(" %d\n", DNS__16BIT(aptr + 2)); /* preference */
p = aptr + 4;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s\n", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s\n", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s\n", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s", name.as_char);
ares_free_string(name.as_char);
break;
default:
printf("\t[Unknown RR; cannot parse]");
break;
}
printf("\n");
return aptr + dlen;
}
inline static const unsigned char *CheckPatternAfterParseAnswer(struct DNSTask *dnstask, const unsigned char *aptr, const unsigned char *abuf, int alen) {
const unsigned char *p;
int type, dnsclass, ttl, dlen, status;
long len;
char addr[46];
/*
if (task->LObjId == 1148) raise(SIGTRAP);
*/
union {
unsigned char * as_uchar;
char * as_char;
} name;
status = ares_expand_name(aptr, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
aptr += len;
if (aptr + RRFIXEDSZ > abuf + alen) {
ares_free_string(name.as_char);
return NULL;
}
type = DNS_RR_TYPE(aptr);
dnsclass = DNS_RR_CLASS(aptr);
ttl = DNS_RR_TTL(aptr);
dlen = DNS_RR_LEN(aptr);
aptr += RRFIXEDSZ;
if (aptr + dlen > abuf + alen) {
ares_free_string(name.as_char);
return NULL;
}
ares_free_string(name.as_char);
switch (type) {
case T_CNAME:
case T_MB:
case T_MD:
case T_MF:
case T_MG:
case T_MR:
case T_NS:
case T_PTR:
status = ares_expand_name(aptr, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS) {
debug("error T_%s compare, %s andd ttl %d error - %d", type_name(type), dnstask->taskPattern, dnstask->taskTTL, status);
return NULL;
}
debug("T_%s compare, %s:%08x on %s and ttl %d on %d", type_name(type), dnstask->taskPattern, dnstask->taskPattern, name.as_char, ttl, dnstask->taskTTL);
if ((dnstask->taskPattern[0] == 0 or !memcmp(name.as_char, dnstask->taskPattern, dnstask->taskPatternLen)) and(dnstask->taskTTL == 0 or ttl == dnstask->taskTTL)) {
dnstask->task->code = STATE_DONE;
}
ares_free_string(name.as_char);
break;
case T_HINFO:
/* The RR data is two length-counted character strings. */
p = aptr;
len = *p;
if (p + len + 1 > aptr + dlen)
return NULL;
debug("\t%.*s", (int) len, p + 1);
p += len + 1;
len = *p;
if (p + len + 1 > aptr + dlen)
return NULL;
debug("\t%.*s", (int) len, p + 1);
break;
case T_MINFO:
/* The RR data is two domain names. */
p = aptr;
status = ares_expand_name(p, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
debug("\t%s.", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_name(p, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
debug("\t%s.", name.as_char);
ares_free_string(name.as_char);
break;
case T_MX:
if (dlen < 2) {
return NULL;
}
status = ares_expand_name(aptr + 2, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS) {
return NULL;
}
debug("T_MX compare %s on %s and ttl %d on %d\n", dnstask->taskPattern, name.as_char, ttl, dnstask->taskTTL);
if ((dnstask->taskPattern[0] = 0 or !memcmp(name.as_char, dnstask->taskPattern, dnstask->taskPatternLen)) and(dnstask->taskTTL == 0 or ttl == dnstask->taskTTL)) {
dnstask->task->code = STATE_DONE;
}
ares_free_string(name.as_char);
break;
case T_SOA:
/* The RR data is two domain names and then five four-byte
* numbers giving the serial number and some timeouts.
*/
p = aptr;
status = ares_expand_name(p, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
debug("\t%s.", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_name(p, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
debug("\t\t\t\t\t\t%s.", name.as_char);
ares_free_string(name.as_char);
p += len;
if (p + 20 > aptr + dlen)
return NULL;
debug("\t\t\t\t\t\t( %lu %lu %lu %lu %lu )",
(unsigned long) DNS__32BIT(p), (unsigned long) DNS__32BIT(p + 4),
(unsigned long) DNS__32BIT(p + 8), (unsigned long) DNS__32BIT(p + 12),
(unsigned long) DNS__32BIT(p + 16));
break;
case T_TXT:
/* The RR data is one or more length-counted character
* strings. */
p = aptr;
while (p < aptr + dlen) {
len = *p;
if (p + len + 1 > aptr + dlen)
return NULL;
//printf("\t%.*s", (int) len, p + 1);
debug("T_TXT compare %s on %s and ttl %d on %d", dnstask->taskPattern, p + 1, ttl, dnstask->taskTTL);
if (!memcmp(p + 1, dnstask->taskPattern, dnstask->taskPatternLen) and ttl == dnstask->taskTTL) {
dnstask->task->code = STATE_DONE;
}
p += len + 1;
}
break;
case T_A:
/* The RR data is a four-byte Internet address. */
inet_ntop(AF_INET, aptr, addr, sizeof (addr));
debug("T_A compare %s on %s (size %d) and ttl %d on %d", dnstask->taskPattern, addr, dnstask->taskPatternLen, ttl, dnstask->taskTTL);
/*
if (dnstask->task->LObjId == 1056) raise(SIGSEGV);
*/
if (dlen == 4 and(dnstask->taskPattern[0] == 0 or !memcmp(addr, dnstask->taskPattern, dnstask->taskPatternLen)) and(dnstask->taskTTL == 0 or ttl == dnstask->taskTTL)) {
dnstask->task->code = STATE_DONE;
}
break;
case T_AAAA:
/* The RR data is a 16-byte IPv6 address. */
if (dlen != 16)
return NULL;
debug("\t%s", inet_ntop(AF_INET6, aptr, addr, sizeof (addr)));
break;
case T_WKS:
/* Not implemented yet */
break;
case T_SRV:
/* The RR data is three two-byte numbers representing the
* priority, weight, and port, followed by a domain name.
*/
printf("\t%d", DNS__16BIT(aptr));
printf(" %d", DNS__16BIT(aptr + 2));
printf(" %d", DNS__16BIT(aptr + 4));
status = ares_expand_name(aptr + 6, abuf, alen, &name.as_char, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t%s.", name.as_char);
ares_free_string(name.as_char);
break;
case T_NAPTR:
printf("\t%d", DNS__16BIT(aptr)); /* order */
printf(" %d\n", DNS__16BIT(aptr + 2)); /* preference */
p = aptr + 4;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s\n", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s\n", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s\n", name.as_char);
ares_free_string(name.as_char);
p += len;
status = ares_expand_string(p, abuf, alen, &name.as_uchar, &len);
if (status != ARES_SUCCESS)
return NULL;
printf("\t\t\t\t\t\t%s", name.as_char);
ares_free_string(name.as_char);
break;
default:
printf("\t[Unknown RR; cannot parse]");
break;
}
if (dnstask->task->code != STATE_DONE) {
return aptr + dlen;
} else {
return NULL;
}
}
