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fix DNS problem with pbuf chain.

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This commit is contained in:
fbernon 2007-11-18 20:54:44 +00:00
parent 8ff1194b6a
commit 8c0e6de00a
3 changed files with 59 additions and 61 deletions
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2
src/core/dhcp.c
View File

@ -523,7 +523,7 @@ static void dhcp_handle_ack(struct netif *netif)
#endif /* LWIP_DNS */ #endif /* LWIP_DNS */
} }
#if LWIP_DNS #if LWIP_DNS
dns_setserver( n, &ip_addr_any); dns_setserver( n, (struct ip_addr *)(&ip_addr_any));
#endif /* LWIP_DNS */ #endif /* LWIP_DNS */
} }
} }

114
src/core/dns.c
View File

@ -65,7 +65,6 @@
*----------------------------------------------------------------------------*/ *----------------------------------------------------------------------------*/
/** @todo: define good default values (rfc compliance) */ /** @todo: define good default values (rfc compliance) */
/** @todo: pbuf chain not yet supported */
/** @todo: improve answer parsing, more checkings... */ /** @todo: improve answer parsing, more checkings... */
/*----------------------------------------------------------------------------- /*-----------------------------------------------------------------------------
@ -216,9 +215,10 @@ static void dns_check_entries(void);
/* DNS variables */ /* DNS variables */
static struct udp_pcb *dns_pcb; static struct udp_pcb *dns_pcb;
static struct dns_table_entry dns_table[DNS_TABLE_SIZE];
static u8_t dns_seqno; static u8_t dns_seqno;
static struct dns_table_entry dns_table[DNS_TABLE_SIZE];
static struct ip_addr dns_servers[DNS_MAX_SERVERS]; static struct ip_addr dns_servers[DNS_MAX_SERVERS];
static u8_t dns_payload[DNS_MSG_SIZE];
/** /**
* Initialize the resolver and configure which DNS server to use for queries. * Initialize the resolver and configure which DNS server to use for queries.
@ -493,9 +493,9 @@ dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16
struct dns_table_entry *pEntry; struct dns_table_entry *pEntry;
u8_t nquestions, nanswers; u8_t nquestions, nanswers;
/* is the dns message in a pbuf chain ? */ /* is the dns message too big ? */
if (p->next != NULL) { if (p->tot_len > DNS_MSG_SIZE) {
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: pbuf chain not yet supported\n")); LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: pbuf too big\n"));
pbuf_free(p); pbuf_free(p);
return; return;
} }
@ -508,68 +508,70 @@ dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16
} }
/** @todo: check RFC1035 - 7.3. Processing responses */ /** @todo: check RFC1035 - 7.3. Processing responses */
/* copy dns payload inside static buffer for processing */
if (pbuf_copy_partial(p, dns_payload, p->tot_len, 0) == p->tot_len) {
/* The ID in the DNS header should be our entry into the name table. */
hdr = (struct dns_hdr *)dns_payload;
i = htons(hdr->id);
if(i < DNS_TABLE_SIZE) {
pEntry = &dns_table[i];
if(pEntry->state == DNS_STATE_ASKING) {
/* This entry is now completed. */
pEntry->state = DNS_STATE_DONE;
pEntry->ttl = DNS_TTL_ENTRY;
pEntry->err = hdr->flags2 & DNS_FLAG2_ERR_MASK;
/* The ID in the DNS header should be our entry into the name table. */ /* We only care about the question(s) and the answers. The authrr
hdr = (struct dns_hdr *)p->payload; and the extrarr are simply discarded. */
i = htons(hdr->id); nquestions = htons(hdr->numquestions);
if(i < DNS_TABLE_SIZE) { nanswers = htons(hdr->numanswers);
pEntry = &dns_table[i];
if(pEntry->state == DNS_STATE_ASKING) {
/* This entry is now completed. */
pEntry->state = DNS_STATE_DONE;
pEntry->ttl = DNS_TTL_ENTRY;
pEntry->err = hdr->flags2 & DNS_FLAG2_ERR_MASK;
/* We only care about the question(s) and the answers. The authrr /* Check for error. If so, call callback to inform. */
and the extrarr are simply discarded. */ if (((hdr->flags1 & DNS_FLAG1_RESPONSE)==0) ||(pEntry->err != 0) || (nquestions != 1)) {
nquestions = htons(hdr->numquestions); LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in flags\n", pEntry->name));
nanswers = htons(hdr->numanswers);
/* Check for error. If so, call callback to inform. */
if (((hdr->flags1 & DNS_FLAG1_RESPONSE)==0) ||(pEntry->err != 0) || (nquestions != 1)) {
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in flags\n", pEntry->name));
/* call specified callback function if provided */
if (pEntry->found)
(*pEntry->found)(pEntry->name, NULL, pEntry->arg);
/* flush this entry */
pEntry->state = DNS_STATE_UNUSED;
pEntry->found = NULL;
/* free pbuf */
pbuf_free(p);
return;
}
/* 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)) + sizeof(struct dns_query);
while(nanswers > 0) {
/* skip answer resource record's host name */
pHostname = (char *) dns_parse_name((unsigned char *)pHostname);
/* Check for IP address type and Internet class. Others are discarded. */
ans = (struct dns_answer *)pHostname;
if((ntohs(ans->type) == DNS_RRTYPE_A) && (ntohs(ans->class) == DNS_RRCLASS_IN) && (ntohs(ans->len) == sizeof(struct ip_addr)) ) {
/* read the IP address after answer resource record's header */
pEntry->ipaddr = (*((struct ip_addr*)(ans+1)));
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": response = ", pEntry->name));
ip_addr_debug_print(DNS_DEBUG, (&(pEntry->ipaddr)));
LWIP_DEBUGF(DNS_DEBUG, ("\n"));
/* call specified callback function if provided */ /* call specified callback function if provided */
if (pEntry->found) if (pEntry->found)
(*pEntry->found)(pEntry->name, &pEntry->ipaddr, pEntry->arg); (*pEntry->found)(pEntry->name, NULL, pEntry->arg);
/* flush this entry */
pEntry->state = DNS_STATE_UNUSED;
pEntry->found = NULL;
/* free pbuf */ /* free pbuf */
pbuf_free(p); pbuf_free(p);
return; return;
} else {
pHostname = pHostname + sizeof(struct dns_answer) + htons(ans->len);
} }
--nanswers;
/* 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 *)dns_payload + sizeof(struct dns_hdr)) + sizeof(struct dns_query);
while(nanswers > 0) {
/* skip answer resource record's host name */
pHostname = (char *) dns_parse_name((unsigned char *)pHostname);
/* Check for IP address type and Internet class. Others are discarded. */
ans = (struct dns_answer *)pHostname;
if((ntohs(ans->type) == DNS_RRTYPE_A) && (ntohs(ans->class) == DNS_RRCLASS_IN) && (ntohs(ans->len) == sizeof(struct ip_addr)) ) {
/* read the IP address after answer resource record's header */
pEntry->ipaddr = (*((struct ip_addr*)(ans+1)));
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": response = ", pEntry->name));
ip_addr_debug_print(DNS_DEBUG, (&(pEntry->ipaddr)));
LWIP_DEBUGF(DNS_DEBUG, ("\n"));
/* call specified callback function if provided */
if (pEntry->found)
(*pEntry->found)(pEntry->name, &pEntry->ipaddr, pEntry->arg);
/* free pbuf */
pbuf_free(p);
return;
} else {
pHostname = pHostname + sizeof(struct dns_answer) + htons(ans->len);
}
--nanswers;
}
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in response\n", pEntry->name));
} }
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in response\n", pEntry->name));
} }
} }
/* free pbuf */ /* free pbuf */
pbuf_free(p); pbuf_free(p);
} }

4
src/core/init.c
View File

@ -194,10 +194,6 @@ lwip_sanity_check(void)
if (TCP_WND < TCP_MSS) if (TCP_WND < TCP_MSS)
LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_WND is smaller than MSS\n")); LWIP_PLATFORM_DIAG(("lwip_sanity_check: WARNING: TCP_WND is smaller than MSS\n"));
#endif /* LWIP_TCP */ #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 */ #else /* LWIP_DEBUG */
#define lwip_sanity_check() #define lwip_sanity_check()