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Minor changes on DNS client.

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This commit is contained in:
fbernon
2007-11-18 14:19:27 +00:00
parent 6c8b3e3b58
commit edc46281a4
6 changed files with 48 additions and 17 deletions
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16
src/core/dns.c
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@@ -400,13 +400,13 @@ dns_send(const char* name, u8_t id)
memcpy( query, dns_endquery, sizeof(dns_endquery));
// resize pbuf to the exact dns query
/* resize pbuf to the exact dns query */
pbuf_realloc(p, (query+sizeof(dns_endquery))-((char*)(p->payload)));
// send dns packet
/* send dns packet */
udp_send(dns_pcb, p);
// free pbuf
/* free pbuf */
pbuf_free(p);
return ERR_OK;
@@ -485,6 +485,8 @@ dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16
struct dns_hdr *hdr;
struct dns_table_entry *pEntry;
u8_t nquestions, nanswers;
LWIP_ASSERT("dns_recv: pbuf chain not yet supported", (p->next==NULL));
hdr = (struct dns_hdr *)p->payload;
@@ -514,7 +516,7 @@ dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16
nquestions = htons(hdr->numquestions);
nanswers = htons(hdr->numanswers);
/* Skip the name in the question. XXX: This should really be checked
/* Skip the name in the "question" part. This should really be checked
agains the name in the question, to be sure that they match. */
pHostname = (char *) dns_parse_name((unsigned char *)p->payload + sizeof(struct dns_hdr)) + 4/*type(2)+class(2)*/;
@@ -524,7 +526,6 @@ dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16
if(*pHostname & 0xc0) {
/* Compressed name. */
pHostname +=2;
/* printf("Compressed anwser\n");*/
} else {
/* Not compressed name. */
pHostname = (char *) dns_parse_name((unsigned char *)pHostname);
@@ -532,9 +533,6 @@ dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16
/* TODO: isn't it any problem to access to dns_answer fields since pHostname's length can be unaligned? */
ans = (struct dns_answer *)pHostname;
/* printf("Answer: type %x, class %x, ttl %x, length %x\n",
htons(ans->type), htons(ans->class), (htons(ans->ttl[0])
<< 16) | htons(ans->ttl[1]), htons(ans->len));*/
/* Check for IP address type and Internet class. Others are discarded. */
if((ntohs(ans->type) == DNS_RRTYPE_A) && (ntohs(ans->class) == DNS_RRCLASS_IN) && (ntohs(ans->len) == 4/*IPv4 address*/) ) {
@@ -548,7 +546,7 @@ dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16
(*pEntry->found)(pEntry->name, &pEntry->ipaddr, pEntry->arg);
return;
} else {
pHostname = pHostname + 10 + htons(ans->len);
pHostname = pHostname + 10 /*type(2)+class(2)+ttl(4)+len(2)*/ + htons(ans->len);
}
--nanswers;
}

4
src/core/init.c
View File

@@ -194,6 +194,10 @@ lwip_sanity_check(void)
if (TCP_WND < TCP_MSS)
LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_WND is smaller than MSS\n"));
#endif /* LWIP_TCP */
#if LWIP_DNS
if (PBUF_POOL_BUFSIZE<(PBUF_LINK_HLEN+PBUF_IP_HLEN+PBUF_TRANSPORT_HLEN+DNS_MSG_SIZE))
LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: UDP messages for DNS could need until 512 bytes\n"));
#endif /* LWIP_DNS */
}
#else /* LWIP_DEBUG */
#define lwip_sanity_check()