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-rw-r--r--nuttx/netutils/resolv/resolv.c553
1 files changed, 295 insertions, 258 deletions
diff --git a/nuttx/netutils/resolv/resolv.c b/nuttx/netutils/resolv/resolv.c
index 0a38faea8..14159e906 100644
--- a/nuttx/netutils/resolv/resolv.c
+++ b/nuttx/netutils/resolv/resolv.c
@@ -1,6 +1,5 @@
/* uip-resolv.c
* DNS host name to IP address resolver.
- * Author: Adam Dunkels <adam@dunkels.com>
*
* The uIP DNS resolver functions are used to lookup a hostname and
* map it to a numerical IP address. It maintains a list of resolved
@@ -12,8 +11,14 @@
* the resolver code calls a callback function called resolv_found()
* that must be implemented by the module that uses the resolver.
*
- * Copyright (c) 2002-2003, Adam Dunkels.
- * All rights reserved.
+ * Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Based heavily on portions of uIP:
+ *
+ * Author: Adam Dunkels <adam@dunkels.com>
+ * Copyright (c) 2002-2003, Adam Dunkels.
+ * All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -39,11 +44,11 @@
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
- * This file is part of the uIP TCP/IP stack.
- *
- * $Id: resolv.c,v 1.1.1.1 2007-08-26 23:07:05 patacongo Exp $
- *
- */
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
#include <sys/types.h>
#include <string.h>
@@ -51,17 +56,24 @@
#include <net/uip/uip.h>
#include <net/uip/resolv.h>
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+#ifndef CONFIG_NET_RESOLV_ENTRIES
+#define RESOLV_ENTRIES 4
+#else /* CONFIG_NET_RESOLV_ENTRIES */
+#define RESOLV_ENTRIES CONFIG_NET_RESOLV_ENTRIES
+#endif /* CONFIG_NET_RESOLV_ENTRIES */
+
#ifndef NULL
#define NULL (void *)0
#endif /* NULL */
-/** \internal The maximum number of retries when asking for a name. */
+/* The maximum number of retries when asking for a name */
+
#define MAX_RETRIES 8
-/** \internal The DNS message header. */
-struct dns_hdr {
- uint16 id;
- uint8 flags1, flags2;
#define DNS_FLAG1_RESPONSE 0x80
#define DNS_FLAG1_OPCODE_STATUS 0x10
#define DNS_FLAG1_OPCODE_INVERSE 0x08
@@ -73,16 +85,37 @@ struct dns_hdr {
#define DNS_FLAG2_ERR_MASK 0x0f
#define DNS_FLAG2_ERR_NONE 0x00
#define DNS_FLAG2_ERR_NAME 0x03
+
+#define STATE_UNUSED 0
+#define STATE_NEW 1
+#define STATE_ASKING 2
+#define STATE_DONE 3
+#define STATE_ERROR 4
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/* The DNS message header */
+
+struct dns_hdr
+{
+ uint16 id;
+ uint8 flags1, flags2;
uint16 numquestions;
uint16 numanswers;
uint16 numauthrr;
uint16 numextrarr;
};
-/** \internal The DNS answer message structure. */
-struct dns_answer {
+/* The DNS answer message structure */
+
+struct dns_answer
+{
/* DNS answer record starts with either a domain name or a pointer
- to a name already present somewhere in the packet. */
+ * to a name already present somewhere in the packet.
+ */
+
uint16 type;
uint16 class;
uint16 ttl[2];
@@ -90,12 +123,8 @@ struct dns_answer {
uip_ipaddr_t ipaddr;
};
-struct namemap {
-#define STATE_UNUSED 0
-#define STATE_NEW 1
-#define STATE_ASKING 2
-#define STATE_DONE 3
-#define STATE_ERROR 4
+struct namemap
+{
uint8 state;
uint8 tmr;
uint8 retries;
@@ -105,51 +134,43 @@ struct namemap {
uip_ipaddr_t ipaddr;
};
-#ifndef CONFIG_UIP_RESOLV_ENTRIES
-#define RESOLV_ENTRIES 4
-#else /* CONFIG_UIP_RESOLV_ENTRIES */
-#define RESOLV_ENTRIES CONFIG_UIP_RESOLV_ENTRIES
-#endif /* CONFIG_UIP_RESOLV_ENTRIES */
-
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
static struct namemap names[RESOLV_ENTRIES];
-
static uint8 seqno;
-
static struct uip_udp_conn *resolv_conn = NULL;
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/* Walk through a compact encoded DNS name and return the end of it. */
-/*---------------------------------------------------------------------------*/
-/** \internal
- * Walk through a compact encoded DNS name and return the end of it.
- *
- * \return The end of the name.
- */
-/*---------------------------------------------------------------------------*/
static unsigned char *parse_name(unsigned char *query)
{
unsigned char n;
- do {
- n = *query++;
+ do
+ {
+ n = *query++;
- while(n > 0)
- {
- ++query;
- --n;
- };
- } while(*query != 0);
+ while(n > 0)
+ {
+ ++query;
+ --n;
+ }
+ }
+ while(*query != 0);
return query + 1;
}
-/*---------------------------------------------------------------------------*/
-/** \internal
- * Runs through the list of names to see if there are any that have
+/* Runs through the list of names to see if there are any that have
* not yet been queried and, if so, sends out a query.
*/
-/*---------------------------------------------------------------------------*/
-static void
-check_entries(void)
+
+static void check_entries(void)
{
register struct dns_hdr *hdr;
char *query, *nptr, *nameptr;
@@ -157,66 +178,73 @@ check_entries(void)
static uint8 n;
register struct namemap *namemapptr;
- for(i = 0; i < RESOLV_ENTRIES; ++i) {
- namemapptr = &names[i];
- if(namemapptr->state == STATE_NEW ||
- namemapptr->state == STATE_ASKING) {
- if(namemapptr->state == STATE_ASKING) {
- if(--namemapptr->tmr == 0) {
- if(++namemapptr->retries == MAX_RETRIES) {
- namemapptr->state = STATE_ERROR;
- resolv_found(namemapptr->name, NULL);
- continue;
- }
- namemapptr->tmr = namemapptr->retries;
- } else {
- /* printf("Timer %d\n", namemapptr->tmr);*/
- /* Its timer has not run out, so we move on to next
- entry. */
- continue;
- }
- } else {
- namemapptr->state = STATE_ASKING;
- namemapptr->tmr = 1;
- namemapptr->retries = 0;
- }
- hdr = (struct dns_hdr *)uip_appdata;
- memset(hdr, 0, sizeof(struct dns_hdr));
- hdr->id = htons(i);
- hdr->flags1 = DNS_FLAG1_RD;
- hdr->numquestions = HTONS(1);
- query = (char *)uip_appdata + 12;
- nameptr = namemapptr->name;
- --nameptr;
- /* Convert hostname into suitable query format. */
- do {
- ++nameptr;
- nptr = query;
- ++query;
- for(n = 0; *nameptr != '.' && *nameptr != 0; ++nameptr) {
- *query = *nameptr;
- ++query;
- ++n;
- }
- *nptr = n;
- } while(*nameptr != 0);
- {
- static unsigned char endquery[] =
- {0,0,1,0,1};
- memcpy(query, endquery, 5);
- }
- uip_udp_send((unsigned char)(query + 5 - (char *)uip_appdata));
- break;
+ for(i = 0; i < RESOLV_ENTRIES; ++i)
+ {
+ namemapptr = &names[i];
+ if (namemapptr->state == STATE_NEW ||
+ namemapptr->state == STATE_ASKING)
+ {
+ if (namemapptr->state == STATE_ASKING)
+ {
+ if (--namemapptr->tmr == 0)
+ {
+ if (++namemapptr->retries == MAX_RETRIES)
+ {
+ namemapptr->state = STATE_ERROR;
+ resolv_found(namemapptr->name, NULL);
+ continue;
+ }
+ namemapptr->tmr = namemapptr->retries;
+ }
+ else
+ {
+ /* Its timer has not run out, so we move on to next entry. */
+ continue;
+ }
+ }
+ else
+ {
+ namemapptr->state = STATE_ASKING;
+ namemapptr->tmr = 1;
+ namemapptr->retries = 0;
+ }
+ hdr = (struct dns_hdr *)uip_appdata;
+ memset(hdr, 0, sizeof(struct dns_hdr));
+ hdr->id = htons(i);
+ hdr->flags1 = DNS_FLAG1_RD;
+ hdr->numquestions = HTONS(1);
+ query = (char *)uip_appdata + 12;
+ nameptr = namemapptr->name;
+ --nameptr;
+
+ /* Convert hostname into suitable query format. */
+ do
+ {
+ ++nameptr;
+ nptr = query;
+ ++query;
+ for (n = 0; *nameptr != '.' && *nameptr != 0; ++nameptr)
+ {
+ *query = *nameptr;
+ ++query;
+ ++n;
+ }
+ *nptr = n;
+ }
+ while(*nameptr != 0);
+ {
+ static unsigned char endquery[] = {0,0,1,0,1};
+ memcpy(query, endquery, 5);
+ }
+ uip_udp_send((unsigned char)(query + 5 - (char *)uip_appdata));
+ break;
+ }
}
- }
}
-/*---------------------------------------------------------------------------*/
-/** \internal
- * Called when new UDP data arrives.
- */
-/*---------------------------------------------------------------------------*/
-static void
-newdata(void)
+
+/* Called when new UDP data arrives */
+
+static void newdata(void)
{
unsigned char *nameptr;
struct dns_answer *ans;
@@ -226,114 +254,127 @@ newdata(void)
register struct namemap *namemapptr;
hdr = (struct dns_hdr *)uip_appdata;
- /* printf("ID %d\n", htons(hdr->id));
- printf("Query %d\n", hdr->flags1 & DNS_FLAG1_RESPONSE);
- printf("Error %d\n", hdr->flags2 & DNS_FLAG2_ERR_MASK);
- printf("Num questions %d, answers %d, authrr %d, extrarr %d\n",
- htons(hdr->numquestions),
- htons(hdr->numanswers),
- htons(hdr->numauthrr),
- htons(hdr->numextrarr));
- */
+
+ dbg( "ID %d\n", htons(hdr->id));
+ dbg( "Query %d\n", hdr->flags1 & DNS_FLAG1_RESPONSE);
+ dbg( "Error %d\n", hdr->flags2 & DNS_FLAG2_ERR_MASK);
+ dbg( "Num questions %d, answers %d, authrr %d, extrarr %d\n",
+ htons(hdr->numquestions), htons(hdr->numanswers),
+ htons(hdr->numauthrr), htons(hdr->numextrarr));
/* The ID in the DNS header should be our entry into the name
- table. */
+ * table.
+ */
+
i = htons(hdr->id);
namemapptr = &names[i];
- if(i < RESOLV_ENTRIES &&
- namemapptr->state == STATE_ASKING) {
-
- /* This entry is now finished. */
- namemapptr->state = STATE_DONE;
- namemapptr->err = hdr->flags2 & DNS_FLAG2_ERR_MASK;
-
- /* Check for error. If so, call callback to inform. */
- if(namemapptr->err != 0) {
- namemapptr->state = STATE_ERROR;
- resolv_found(namemapptr->name, NULL);
- return;
- }
+ if (i < RESOLV_ENTRIES && namemapptr->state == STATE_ASKING)
+ {
+ /* This entry is now finished */
- /* We only care about the question(s) and the answers. The authrr
- and the extrarr are simply discarded. */
- nquestions = htons(hdr->numquestions);
- nanswers = htons(hdr->numanswers);
-
- /* Skip the name in the question. XXX: This should really be
- checked agains the name in the question, to be sure that they
- match. */
- nameptr = parse_name((unsigned char *)uip_appdata + 12) + 4;
-
- while(nanswers > 0) {
- /* The first byte in the answer resource record determines if it
- is a compressed record or a normal one. */
- if(*nameptr & 0xc0) {
- /* Compressed name. */
- nameptr +=2;
- /* printf("Compressed anwser\n");*/
- } else {
- /* Not compressed name. */
- nameptr = parse_name(nameptr);
- }
-
- ans = (struct dns_answer *)nameptr;
- /* 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(ans->type == HTONS(1) &&
- ans->class == HTONS(1) &&
- ans->len == HTONS(4)) {
- /* printf("IP address %d.%d.%d.%d\n",
- htons(ans->ipaddr[0]) >> 8,
- htons(ans->ipaddr[0]) & 0xff,
- htons(ans->ipaddr[1]) >> 8,
- htons(ans->ipaddr[1]) & 0xff);*/
- /* XXX: we should really check that this IP address is the one
- we want. */
- namemapptr->ipaddr[0] = ans->ipaddr[0];
- namemapptr->ipaddr[1] = ans->ipaddr[1];
-
- resolv_found(namemapptr->name, namemapptr->ipaddr);
- return;
- } else {
- nameptr = nameptr + 10 + htons(ans->len);
- }
- --nanswers;
- }
- }
+ namemapptr->state = STATE_DONE;
+ namemapptr->err = hdr->flags2 & DNS_FLAG2_ERR_MASK;
+
+ /* Check for error. If so, call callback to inform */
+
+ if (namemapptr->err != 0)
+ {
+ namemapptr->state = STATE_ERROR;
+ resolv_found(namemapptr->name, NULL);
+ return;
+ }
+
+ /* We only care about the question(s) and the answers. The authrr
+ * and the extrarr are simply discarded.
+ */
+
+ nquestions = htons(hdr->numquestions);
+ nanswers = htons(hdr->numanswers);
+
+ /* Skip the name in the question. XXX: This should really be
+ * checked agains the name in the question, to be sure that they
+ * match.
+ */
+
+ nameptr = parse_name((unsigned char *)uip_appdata + 12) + 4;
+ while(nanswers > 0)
+ {
+ /* The first byte in the answer resource record determines if it
+ * is a compressed record or a normal one.
+ */
+
+ if (*nameptr & 0xc0)
+ {
+ /* Compressed name. */
+
+ nameptr +=2;
+ dbg("Compressed anwser\n");
+ }
+ else
+ {
+ /* Not compressed name. */
+ nameptr = parse_name(nameptr);
+ }
+
+ ans = (struct dns_answer *)nameptr;
+ dbg("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 (ans->type == HTONS(1) && ans->class == HTONS(1) && ans->len == HTONS(4))
+ {
+ dbg("IP address %d.%d.%d.%d\n",
+ htons(ans->ipaddr[0]) >> 8, htons(ans->ipaddr[0]) & 0xff,
+ htons(ans->ipaddr[1]) >> 8, htons(ans->ipaddr[1]) & 0xff);
+
+ /* XXX: we should really check that this IP address is the one
+ * we want.
+ */
+
+ namemapptr->ipaddr[0] = ans->ipaddr[0];
+ namemapptr->ipaddr[1] = ans->ipaddr[1];
+
+ resolv_found(namemapptr->name, namemapptr->ipaddr);
+ return;
+ }
+ else
+ {
+ nameptr = nameptr + 10 + htons(ans->len);
+ }
+ --nanswers;
+ }
+ }
}
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
/* This function is called by the UIP interrupt handling logic whenevent an
* event of interest occurs.
*/
void uip_interrupt_udp_event(void)
{
- if(uip_udp_conn->rport == HTONS(53))
+ if (uip_udp_conn->rport == HTONS(53))
{
- if(uip_poll())
+ if (uip_poll())
{
check_entries();
}
- if(uip_newdata())
+ if (uip_newdata())
{
newdata();
}
}
}
-/**
- * Queues a name so that a question for the name will be sent out.
- *
- * \param name The hostname that is to be queried.
- */
-/*---------------------------------------------------------------------------*/
-void
-resolv_query(char *name)
+/* Queues a name so that a question for the name will be sent out. */
+
+void resolv_query(char *name)
{
static uint8 i;
static uint8 lseq, lseqi;
@@ -341,110 +382,106 @@ resolv_query(char *name)
lseq = lseqi = 0;
- for(i = 0; i < RESOLV_ENTRIES; ++i) {
- nameptr = &names[i];
- if(nameptr->state == STATE_UNUSED) {
- break;
- }
- if(seqno - nameptr->seqno > lseq) {
- lseq = seqno - nameptr->seqno;
- lseqi = i;
+ for(i = 0; i < RESOLV_ENTRIES; ++i)
+ {
+ nameptr = &names[i];
+ if (nameptr->state == STATE_UNUSED)
+ {
+ break;
+ }
+ if (seqno - nameptr->seqno > lseq)
+ {
+ lseq = seqno - nameptr->seqno;
+ lseqi = i;
+ }
}
- }
- if(i == RESOLV_ENTRIES) {
- i = lseqi;
- nameptr = &names[i];
- }
+ if (i == RESOLV_ENTRIES)
+ {
+ i = lseqi;
+ nameptr = &names[i];
+ }
- /* printf("Using entry %d\n", i);*/
+ dbg("Using entry %d\n", i);
strcpy(nameptr->name, name);
nameptr->state = STATE_NEW;
nameptr->seqno = seqno;
++seqno;
}
-/*---------------------------------------------------------------------------*/
-/**
- * Look up a hostname in the array of known hostnames.
+
+/* Look up a hostname in the array of known hostnames.
*
- * \note This function only looks in the internal array of known
+ * Note: This function only looks in the internal array of known
* hostnames, it does not send out a query for the hostname if none
* was found. The function resolv_query() can be used to send a query
* for a hostname.
*
- * \return A pointer to a 4-byte representation of the hostname's IP
+ * Return A pointer to a 4-byte representation of the hostname's IP
* address, or NULL if the hostname was not found in the array of
* hostnames.
*/
-/*---------------------------------------------------------------------------*/
-uint16 *
-resolv_lookup(char *name)
+
+uint16 *resolv_lookup(char *name)
{
static uint8 i;
struct namemap *nameptr;
/* Walk through the list to see if the name is in there. If it is
- not, we return NULL. */
- for(i = 0; i < RESOLV_ENTRIES; ++i) {
- nameptr = &names[i];
- if(nameptr->state == STATE_DONE &&
- strcmp(name, nameptr->name) == 0) {
- return nameptr->ipaddr;
+ * not, we return NULL.
+ */
+
+ for(i = 0; i < RESOLV_ENTRIES; ++i)
+ {
+ nameptr = &names[i];
+ if (nameptr->state == STATE_DONE && strcmp(name, nameptr->name) == 0)
+ {
+ return nameptr->ipaddr;
+ }
}
- }
return NULL;
}
-/*---------------------------------------------------------------------------*/
-/**
- * Obtain the currently configured DNS server.
+
+/* Obtain the currently configured DNS server.
*
- * \return A pointer to a 4-byte representation of the IP address of
+ * Return: A pointer to a 4-byte representation of the IP address of
* the currently configured DNS server or NULL if no DNS server has
* been configured.
*/
-/*---------------------------------------------------------------------------*/
-uint16 *
-resolv_getserver(void)
+
+uint16 *resolv_getserver(void)
{
- if(resolv_conn == NULL) {
- return NULL;
- }
+ if (resolv_conn == NULL)
+ {
+ return NULL;
+ }
return resolv_conn->ripaddr;
}
-/*---------------------------------------------------------------------------*/
-/**
- * Configure which DNS server to use for queries.
+
+/* Configure which DNS server to use for queries.
*
- * \param dnsserver A pointer to a 4-byte representation of the IP
+ * dnsserver A pointer to a 4-byte representation of the IP
* address of the DNS server to be configured.
*/
-/*---------------------------------------------------------------------------*/
-void
-resolv_conf(uint16 *dnsserver)
+
+void resolv_conf(uint16 *dnsserver)
{
- if(resolv_conn != NULL) {
- uip_udp_remove(resolv_conn);
- }
-
+ if (resolv_conn != NULL)
+ {
+ uip_udp_remove(resolv_conn);
+ }
+
resolv_conn = uip_udp_new(dnsserver, HTONS(53));
}
-/*---------------------------------------------------------------------------*/
-/**
- * Initalize the resolver.
- */
-/*---------------------------------------------------------------------------*/
-void
-resolv_init(void)
+
+/* Initalize the resolver. */
+
+void resolv_init(void)
{
static uint8 i;
- for(i = 0; i < RESOLV_ENTRIES; ++i) {
- names[i].state = STATE_DONE;
- }
-
+ for(i = 0; i < RESOLV_ENTRIES; ++i)
+ {
+ names[i].state = STATE_DONE;
+ }
}
-/*---------------------------------------------------------------------------*/
-
-/** @} */
-/** @} */
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-04 07:20:24 +0000