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| mbed714 |
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/**
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* @file
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* DNS - host name to IP address resolver.
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*
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*/
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/**
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* This file implements a DNS host name to IP address resolver.
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* Port to lwIP from uIP
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* by Jim Pettinato April 2007
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* uIP version Copyright (c) 2002-2003, Adam Dunkels.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote
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* products derived from this software without specific prior
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* written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
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* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
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* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
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* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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*
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* DNS.C
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*
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* The lwIP DNS resolver functions are used to lookup a host name and
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* map it to a numerical IP address. It maintains a list of resolved
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* hostnames that can be queried with the dns_lookup() function.
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* New hostnames can be resolved using the dns_query() function.
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*
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* The lwIP version of the resolver also adds a non-blocking version of
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* gethostbyname() that will work with a raw API application. This function
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* checks for an IP address string first and converts it if it is valid.
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* gethostbyname() then does a dns_lookup() to see if the name is
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* already in the table. If so, the IP is returned. If not, a query is
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* issued and the function returns with a ERR_INPROGRESS status. The app
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* using the dns client must then go into a waiting state.
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*
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* Once a hostname has been resolved (or found to be non-existent),
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* the resolver code calls a specified callback function (which
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* must be implemented by the module that uses the resolver).
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*/
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/*-----------------------------------------------------------------------------
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* RFC 1035 - Domain names - implementation and specification
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* RFC 2181 - Clarifications to the DNS Specification
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*----------------------------------------------------------------------------*/
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/** @todo: define good default values (rfc compliance) */
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/** @todo: improve answer parsing, more checkings... */
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/** @todo: check RFC1035 - 7.3. Processing responses */
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/*-----------------------------------------------------------------------------
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* Includes
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*----------------------------------------------------------------------------*/
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#include "lwip/opt.h"
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#if LWIP_DNS /* don't build if not configured for use in lwipopts.h */
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#include "lwip/udp.h"
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#include "lwip/mem.h"
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#include "lwip/memp.h"
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#include "lwip/dns.h"
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#include <string.h>
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/** DNS server IP address */
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#ifndef DNS_SERVER_ADDRESS
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#define DNS_SERVER_ADDRESS(ipaddr) (ip4_addr_set_u32(ipaddr, ipaddr_addr("208.67.222.222"))) /* resolver1.opendns.com */
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#endif
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/** DNS server port address */
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#ifndef DNS_SERVER_PORT
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#define DNS_SERVER_PORT 53
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#endif
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/** DNS maximum number of retries when asking for a name, before "timeout". */
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#ifndef DNS_MAX_RETRIES
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#define DNS_MAX_RETRIES 4
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#endif
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/** DNS resource record max. TTL (one week as default) */
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#ifndef DNS_MAX_TTL
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#define DNS_MAX_TTL 604800
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#endif
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/* DNS protocol flags */
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#define DNS_FLAG1_RESPONSE 0x80
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#define DNS_FLAG1_OPCODE_STATUS 0x10
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#define DNS_FLAG1_OPCODE_INVERSE 0x08
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#define DNS_FLAG1_OPCODE_STANDARD 0x00
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#define DNS_FLAG1_AUTHORATIVE 0x04
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#define DNS_FLAG1_TRUNC 0x02
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#define DNS_FLAG1_RD 0x01
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#define DNS_FLAG2_RA 0x80
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#define DNS_FLAG2_ERR_MASK 0x0f
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#define DNS_FLAG2_ERR_NONE 0x00
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#define DNS_FLAG2_ERR_NAME 0x03
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/* DNS protocol states */
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#define DNS_STATE_UNUSED 0
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#define DNS_STATE_NEW 1
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#define DNS_STATE_ASKING 2
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#define DNS_STATE_DONE 3
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#ifdef PACK_STRUCT_USE_INCLUDES
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# include "arch/bpstruct.h"
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#endif
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PACK_STRUCT_BEGIN
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/** DNS message header */
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struct dns_hdr {
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PACK_STRUCT_FIELD(u16_t id);
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PACK_STRUCT_FIELD(u8_t flags1);
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PACK_STRUCT_FIELD(u8_t flags2);
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PACK_STRUCT_FIELD(u16_t numquestions);
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PACK_STRUCT_FIELD(u16_t numanswers);
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PACK_STRUCT_FIELD(u16_t numauthrr);
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PACK_STRUCT_FIELD(u16_t numextrarr);
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} PACK_STRUCT_STRUCT;
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PACK_STRUCT_END
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#ifdef PACK_STRUCT_USE_INCLUDES
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# include "arch/epstruct.h"
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#endif
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#define SIZEOF_DNS_HDR 12
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/** DNS query message structure.
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No packing needed: only used locally on the stack. */
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struct dns_query {
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/* DNS query record starts with either a domain name or a pointer
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to a name already present somewhere in the packet. */
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u16_t type;
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u16_t cls;
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};
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#define SIZEOF_DNS_QUERY 4
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154
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/** DNS answer message structure.
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No packing needed: only used locally on the stack. */
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struct dns_answer {
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/* DNS answer record starts with either a domain name or a pointer
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to a name already present somewhere in the packet. */
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u16_t type;
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u16_t cls;
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u32_t ttl;
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u16_t len;
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};
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#define SIZEOF_DNS_ANSWER 10
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/** DNS table entry */
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168
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struct dns_table_entry {
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u8_t state;
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u8_t numdns;
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u8_t tmr;
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u8_t retries;
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u8_t seqno;
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u8_t err;
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u32_t ttl;
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char name[DNS_MAX_NAME_LENGTH];
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ip_addr_t ipaddr;
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/* pointer to callback on DNS query done */
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dns_found_callback found;
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void *arg;
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};
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183
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#if DNS_LOCAL_HOSTLIST
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#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
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/** Local host-list. For hostnames in this list, no
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* external name resolution is performed */
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static struct local_hostlist_entry *local_hostlist_dynamic;
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#else /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
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/** Defining this allows the local_hostlist_static to be placed in a different
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* linker section (e.g. FLASH) */
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#ifndef DNS_LOCAL_HOSTLIST_STORAGE_PRE
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#define DNS_LOCAL_HOSTLIST_STORAGE_PRE static
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#endif /* DNS_LOCAL_HOSTLIST_STORAGE_PRE */
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/** Defining this allows the local_hostlist_static to be placed in a different
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* linker section (e.g. FLASH) */
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#ifndef DNS_LOCAL_HOSTLIST_STORAGE_POST
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#define DNS_LOCAL_HOSTLIST_STORAGE_POST
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#endif /* DNS_LOCAL_HOSTLIST_STORAGE_POST */
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DNS_LOCAL_HOSTLIST_STORAGE_PRE struct local_hostlist_entry local_hostlist_static[]
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DNS_LOCAL_HOSTLIST_STORAGE_POST = DNS_LOCAL_HOSTLIST_INIT;
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203
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#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
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205
|
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206
|
static void dns_init_local();
|
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|
#endif /* DNS_LOCAL_HOSTLIST */
|
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|
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209
|
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210
|
/* forward declarations */
|
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211
|
static void dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port);
|
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|
static void dns_check_entries(void);
|
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213
|
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214
|
/*-----------------------------------------------------------------------------
|
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215
|
* Globales
|
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216
|
*----------------------------------------------------------------------------*/
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217
|
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218
|
/* DNS variables */
|
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219
|
static struct udp_pcb *dns_pcb;
|
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220
|
static u8_t dns_seqno;
|
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221
|
static struct dns_table_entry dns_table[DNS_TABLE_SIZE];
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222
|
static ip_addr_t dns_servers[DNS_MAX_SERVERS];
|
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223
|
/** Contiguous buffer for processing responses */
|
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224
|
static u8_t dns_payload_buffer[LWIP_MEM_ALIGN_BUFFER(DNS_MSG_SIZE)];
|
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225
|
static u8_t* dns_payload;
|
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226
|
|
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227
|
/**
|
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228
|
* Initialize the resolver: set up the UDP pcb and configure the default server
|
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229
|
* (DNS_SERVER_ADDRESS).
|
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230
|
*/
|
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|
231
|
void
|
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232
|
dns_init()
|
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233
|
{
|
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234
|
ip_addr_t dnsserver;
|
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|
235
|
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236
|
dns_payload = (u8_t *)LWIP_MEM_ALIGN(dns_payload_buffer);
|
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237
|
|
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|
238
|
/* initialize default DNS server address */
|
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239
|
DNS_SERVER_ADDRESS(&dnsserver);
|
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240
|
|
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|
241
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_init: initializing\n"));
|
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242
|
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243
|
/* if dns client not yet initialized... */
|
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|
244
|
if (dns_pcb == NULL) {
|
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245
|
dns_pcb = udp_new();
|
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|
246
|
|
| mbed714 |
0:d616ece2d859
|
247
|
if (dns_pcb != NULL) {
|
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|
248
|
/* initialize DNS table not needed (initialized to zero since it is a
|
| mbed714 |
0:d616ece2d859
|
249
|
* global variable) */
|
| mbed714 |
0:d616ece2d859
|
250
|
LWIP_ASSERT("For implicit initialization to work, DNS_STATE_UNUSED needs to be 0",
|
| mbed714 |
0:d616ece2d859
|
251
|
DNS_STATE_UNUSED == 0);
|
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|
252
|
|
| mbed714 |
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|
253
|
/* initialize DNS client */
|
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|
254
|
udp_bind(dns_pcb, IP_ADDR_ANY, 0);
|
| mbed714 |
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|
255
|
udp_recv(dns_pcb, dns_recv, NULL);
|
| mbed714 |
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|
256
|
|
| mbed714 |
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|
257
|
/* initialize default DNS primary server */
|
| mbed714 |
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|
258
|
dns_setserver(0, &dnsserver);
|
| mbed714 |
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|
259
|
}
|
| mbed714 |
0:d616ece2d859
|
260
|
}
|
| mbed714 |
0:d616ece2d859
|
261
|
#if DNS_LOCAL_HOSTLIST
|
| mbed714 |
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|
262
|
dns_init_local();
|
| mbed714 |
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|
263
|
#endif
|
| mbed714 |
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|
264
|
}
|
| mbed714 |
0:d616ece2d859
|
265
|
|
| mbed714 |
0:d616ece2d859
|
266
|
/**
|
| mbed714 |
0:d616ece2d859
|
267
|
* Initialize one of the DNS servers.
|
| mbed714 |
0:d616ece2d859
|
268
|
*
|
| mbed714 |
0:d616ece2d859
|
269
|
* @param numdns the index of the DNS server to set must be < DNS_MAX_SERVERS
|
| mbed714 |
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|
270
|
* @param dnsserver IP address of the DNS server to set
|
| mbed714 |
0:d616ece2d859
|
271
|
*/
|
| mbed714 |
0:d616ece2d859
|
272
|
void
|
| mbed714 |
0:d616ece2d859
|
273
|
dns_setserver(u8_t numdns, ip_addr_t *dnsserver)
|
| mbed714 |
0:d616ece2d859
|
274
|
{
|
| mbed714 |
0:d616ece2d859
|
275
|
if ((numdns < DNS_MAX_SERVERS) && (dns_pcb != NULL) &&
|
| mbed714 |
0:d616ece2d859
|
276
|
(dnsserver != NULL) && !ip_addr_isany(dnsserver)) {
|
| mbed714 |
0:d616ece2d859
|
277
|
dns_servers[numdns] = (*dnsserver);
|
| mbed714 |
0:d616ece2d859
|
278
|
}
|
| mbed714 |
0:d616ece2d859
|
279
|
}
|
| mbed714 |
0:d616ece2d859
|
280
|
|
| mbed714 |
0:d616ece2d859
|
281
|
/**
|
| mbed714 |
0:d616ece2d859
|
282
|
* Obtain one of the currently configured DNS server.
|
| mbed714 |
0:d616ece2d859
|
283
|
*
|
| mbed714 |
0:d616ece2d859
|
284
|
* @param numdns the index of the DNS server
|
| mbed714 |
0:d616ece2d859
|
285
|
* @return IP address of the indexed DNS server or "ip_addr_any" if the DNS
|
| mbed714 |
0:d616ece2d859
|
286
|
* server has not been configured.
|
| mbed714 |
0:d616ece2d859
|
287
|
*/
|
| mbed714 |
0:d616ece2d859
|
288
|
ip_addr_t
|
| mbed714 |
0:d616ece2d859
|
289
|
dns_getserver(u8_t numdns)
|
| mbed714 |
0:d616ece2d859
|
290
|
{
|
| mbed714 |
0:d616ece2d859
|
291
|
if (numdns < DNS_MAX_SERVERS) {
|
| mbed714 |
0:d616ece2d859
|
292
|
return dns_servers[numdns];
|
| mbed714 |
0:d616ece2d859
|
293
|
} else {
|
| mbed714 |
0:d616ece2d859
|
294
|
return *IP_ADDR_ANY;
|
| mbed714 |
0:d616ece2d859
|
295
|
}
|
| mbed714 |
0:d616ece2d859
|
296
|
}
|
| mbed714 |
0:d616ece2d859
|
297
|
|
| mbed714 |
0:d616ece2d859
|
298
|
/**
|
| mbed714 |
0:d616ece2d859
|
299
|
* The DNS resolver client timer - handle retries and timeouts and should
|
| mbed714 |
0:d616ece2d859
|
300
|
* be called every DNS_TMR_INTERVAL milliseconds (every second by default).
|
| mbed714 |
0:d616ece2d859
|
301
|
*/
|
| mbed714 |
0:d616ece2d859
|
302
|
void
|
| mbed714 |
0:d616ece2d859
|
303
|
dns_tmr(void)
|
| mbed714 |
0:d616ece2d859
|
304
|
{
|
| mbed714 |
0:d616ece2d859
|
305
|
if (dns_pcb != NULL) {
|
| mbed714 |
0:d616ece2d859
|
306
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_tmr: dns_check_entries\n"));
|
| mbed714 |
0:d616ece2d859
|
307
|
dns_check_entries();
|
| mbed714 |
0:d616ece2d859
|
308
|
}
|
| mbed714 |
0:d616ece2d859
|
309
|
}
|
| mbed714 |
0:d616ece2d859
|
310
|
|
| mbed714 |
0:d616ece2d859
|
311
|
#if DNS_LOCAL_HOSTLIST
|
| mbed714 |
0:d616ece2d859
|
312
|
static void
|
| mbed714 |
0:d616ece2d859
|
313
|
dns_init_local()
|
| mbed714 |
0:d616ece2d859
|
314
|
{
|
| mbed714 |
0:d616ece2d859
|
315
|
#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC && defined(DNS_LOCAL_HOSTLIST_INIT)
|
| mbed714 |
0:d616ece2d859
|
316
|
int i;
|
| mbed714 |
0:d616ece2d859
|
317
|
struct local_hostlist_entry *entry;
|
| mbed714 |
0:d616ece2d859
|
318
|
/* Dynamic: copy entries from DNS_LOCAL_HOSTLIST_INIT to list */
|
| mbed714 |
0:d616ece2d859
|
319
|
struct local_hostlist_entry local_hostlist_init[] = DNS_LOCAL_HOSTLIST_INIT;
|
| mbed714 |
0:d616ece2d859
|
320
|
size_t namelen;
|
| mbed714 |
0:d616ece2d859
|
321
|
for (i = 0; i < sizeof(local_hostlist_init) / sizeof(struct local_hostlist_entry); i++) {
|
| mbed714 |
0:d616ece2d859
|
322
|
struct local_hostlist_entry *init_entry = &local_hostlist_init[i];
|
| mbed714 |
0:d616ece2d859
|
323
|
LWIP_ASSERT("invalid host name (NULL)", init_entry->name != NULL);
|
| mbed714 |
0:d616ece2d859
|
324
|
namelen = strlen(init_entry->name);
|
| mbed714 |
0:d616ece2d859
|
325
|
LWIP_ASSERT("namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN", namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN);
|
| mbed714 |
0:d616ece2d859
|
326
|
entry = (struct local_hostlist_entry *)memp_malloc(MEMP_LOCALHOSTLIST);
|
| mbed714 |
0:d616ece2d859
|
327
|
LWIP_ASSERT("mem-error in dns_init_local", entry != NULL);
|
| mbed714 |
0:d616ece2d859
|
328
|
if (entry != NULL) {
|
| mbed714 |
0:d616ece2d859
|
329
|
entry->name = (char*)entry + sizeof(struct local_hostlist_entry);
|
| mbed714 |
0:d616ece2d859
|
330
|
MEMCPY((char*)entry->name, init_entry->name, namelen);
|
| mbed714 |
0:d616ece2d859
|
331
|
((char*)entry->name)[namelen] = 0;
|
| mbed714 |
0:d616ece2d859
|
332
|
entry->addr = init_entry->addr;
|
| mbed714 |
0:d616ece2d859
|
333
|
entry->next = local_hostlist_dynamic;
|
| mbed714 |
0:d616ece2d859
|
334
|
local_hostlist_dynamic = entry;
|
| mbed714 |
0:d616ece2d859
|
335
|
}
|
| mbed714 |
0:d616ece2d859
|
336
|
}
|
| mbed714 |
0:d616ece2d859
|
337
|
#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC && defined(DNS_LOCAL_HOSTLIST_INIT) */
|
| mbed714 |
0:d616ece2d859
|
338
|
}
|
| mbed714 |
0:d616ece2d859
|
339
|
|
| mbed714 |
0:d616ece2d859
|
340
|
/**
|
| mbed714 |
0:d616ece2d859
|
341
|
* Scans the local host-list for a hostname.
|
| mbed714 |
0:d616ece2d859
|
342
|
*
|
| mbed714 |
0:d616ece2d859
|
343
|
* @param hostname Hostname to look for in the local host-list
|
| mbed714 |
0:d616ece2d859
|
344
|
* @return The first IP address for the hostname in the local host-list or
|
| mbed714 |
0:d616ece2d859
|
345
|
* IPADDR_NONE if not found.
|
| mbed714 |
0:d616ece2d859
|
346
|
*/
|
| mbed714 |
0:d616ece2d859
|
347
|
static u32_t
|
| mbed714 |
0:d616ece2d859
|
348
|
dns_lookup_local(const char *hostname)
|
| mbed714 |
0:d616ece2d859
|
349
|
{
|
| mbed714 |
0:d616ece2d859
|
350
|
#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
|
| mbed714 |
0:d616ece2d859
|
351
|
struct local_hostlist_entry *entry = local_hostlist_dynamic;
|
| mbed714 |
0:d616ece2d859
|
352
|
while(entry != NULL) {
|
| mbed714 |
0:d616ece2d859
|
353
|
if(strcmp(entry->name, hostname) == 0) {
|
| mbed714 |
0:d616ece2d859
|
354
|
return ip4_addr_get_u32(&entry->addr);
|
| mbed714 |
0:d616ece2d859
|
355
|
}
|
| mbed714 |
0:d616ece2d859
|
356
|
entry = entry->next;
|
| mbed714 |
0:d616ece2d859
|
357
|
}
|
| mbed714 |
0:d616ece2d859
|
358
|
#else /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
|
| mbed714 |
0:d616ece2d859
|
359
|
int i;
|
| mbed714 |
0:d616ece2d859
|
360
|
for (i = 0; i < sizeof(local_hostlist_static) / sizeof(struct local_hostlist_entry); i++) {
|
| mbed714 |
0:d616ece2d859
|
361
|
if(strcmp(local_hostlist_static[i].name, hostname) == 0) {
|
| mbed714 |
0:d616ece2d859
|
362
|
return ip4_addr_get_u32(&local_hostlist_static[i].addr);
|
| mbed714 |
0:d616ece2d859
|
363
|
}
|
| mbed714 |
0:d616ece2d859
|
364
|
}
|
| mbed714 |
0:d616ece2d859
|
365
|
#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
|
| mbed714 |
0:d616ece2d859
|
366
|
return IPADDR_NONE;
|
| mbed714 |
0:d616ece2d859
|
367
|
}
|
| mbed714 |
0:d616ece2d859
|
368
|
|
| mbed714 |
0:d616ece2d859
|
369
|
#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
|
| mbed714 |
0:d616ece2d859
|
370
|
/** Remove all entries from the local host-list for a specific hostname
|
| mbed714 |
0:d616ece2d859
|
371
|
* and/or IP addess
|
| mbed714 |
0:d616ece2d859
|
372
|
*
|
| mbed714 |
0:d616ece2d859
|
373
|
* @param hostname hostname for which entries shall be removed from the local
|
| mbed714 |
0:d616ece2d859
|
374
|
* host-list
|
| mbed714 |
0:d616ece2d859
|
375
|
* @param addr address for which entries shall be removed from the local host-list
|
| mbed714 |
0:d616ece2d859
|
376
|
* @return the number of removed entries
|
| mbed714 |
0:d616ece2d859
|
377
|
*/
|
| mbed714 |
0:d616ece2d859
|
378
|
int
|
| mbed714 |
0:d616ece2d859
|
379
|
dns_local_removehost(const char *hostname, const ip_addr_t *addr)
|
| mbed714 |
0:d616ece2d859
|
380
|
{
|
| mbed714 |
0:d616ece2d859
|
381
|
int removed = 0;
|
| mbed714 |
0:d616ece2d859
|
382
|
struct local_hostlist_entry *entry = local_hostlist_dynamic;
|
| mbed714 |
0:d616ece2d859
|
383
|
struct local_hostlist_entry *last_entry = NULL;
|
| mbed714 |
0:d616ece2d859
|
384
|
while (entry != NULL) {
|
| mbed714 |
0:d616ece2d859
|
385
|
if (((hostname == NULL) || !strcmp(entry->name, hostname)) &&
|
| mbed714 |
0:d616ece2d859
|
386
|
((addr == NULL) || ip_addr_cmp(&entry->addr, addr))) {
|
| mbed714 |
0:d616ece2d859
|
387
|
struct local_hostlist_entry *free_entry;
|
| mbed714 |
0:d616ece2d859
|
388
|
if (last_entry != NULL) {
|
| mbed714 |
0:d616ece2d859
|
389
|
last_entry->next = entry->next;
|
| mbed714 |
0:d616ece2d859
|
390
|
} else {
|
| mbed714 |
0:d616ece2d859
|
391
|
local_hostlist_dynamic = entry->next;
|
| mbed714 |
0:d616ece2d859
|
392
|
}
|
| mbed714 |
0:d616ece2d859
|
393
|
free_entry = entry;
|
| mbed714 |
0:d616ece2d859
|
394
|
entry = entry->next;
|
| mbed714 |
0:d616ece2d859
|
395
|
memp_free(MEMP_LOCALHOSTLIST, free_entry);
|
| mbed714 |
0:d616ece2d859
|
396
|
removed++;
|
| mbed714 |
0:d616ece2d859
|
397
|
} else {
|
| mbed714 |
0:d616ece2d859
|
398
|
last_entry = entry;
|
| mbed714 |
0:d616ece2d859
|
399
|
entry = entry->next;
|
| mbed714 |
0:d616ece2d859
|
400
|
}
|
| mbed714 |
0:d616ece2d859
|
401
|
}
|
| mbed714 |
0:d616ece2d859
|
402
|
return removed;
|
| mbed714 |
0:d616ece2d859
|
403
|
}
|
| mbed714 |
0:d616ece2d859
|
404
|
|
| mbed714 |
0:d616ece2d859
|
405
|
/**
|
| mbed714 |
0:d616ece2d859
|
406
|
* Add a hostname/IP address pair to the local host-list.
|
| mbed714 |
0:d616ece2d859
|
407
|
* Duplicates are not checked.
|
| mbed714 |
0:d616ece2d859
|
408
|
*
|
| mbed714 |
0:d616ece2d859
|
409
|
* @param hostname hostname of the new entry
|
| mbed714 |
0:d616ece2d859
|
410
|
* @param addr IP address of the new entry
|
| mbed714 |
0:d616ece2d859
|
411
|
* @return ERR_OK if succeeded or ERR_MEM on memory error
|
| mbed714 |
0:d616ece2d859
|
412
|
*/
|
| mbed714 |
0:d616ece2d859
|
413
|
err_t
|
| mbed714 |
0:d616ece2d859
|
414
|
dns_local_addhost(const char *hostname, const ip_addr_t *addr)
|
| mbed714 |
0:d616ece2d859
|
415
|
{
|
| mbed714 |
0:d616ece2d859
|
416
|
struct local_hostlist_entry *entry;
|
| mbed714 |
0:d616ece2d859
|
417
|
size_t namelen;
|
| mbed714 |
0:d616ece2d859
|
418
|
LWIP_ASSERT("invalid host name (NULL)", hostname != NULL);
|
| mbed714 |
0:d616ece2d859
|
419
|
namelen = strlen(hostname);
|
| mbed714 |
0:d616ece2d859
|
420
|
LWIP_ASSERT("namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN", namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN);
|
| mbed714 |
0:d616ece2d859
|
421
|
entry = (struct local_hostlist_entry *)memp_malloc(MEMP_LOCALHOSTLIST);
|
| mbed714 |
0:d616ece2d859
|
422
|
if (entry == NULL) {
|
| mbed714 |
0:d616ece2d859
|
423
|
return ERR_MEM;
|
| mbed714 |
0:d616ece2d859
|
424
|
}
|
| mbed714 |
0:d616ece2d859
|
425
|
entry->name = (char*)entry + sizeof(struct local_hostlist_entry);
|
| mbed714 |
0:d616ece2d859
|
426
|
MEMCPY((char*)entry->name, hostname, namelen);
|
| mbed714 |
0:d616ece2d859
|
427
|
((char*)entry->name)[namelen] = 0;
|
| mbed714 |
0:d616ece2d859
|
428
|
ip_addr_copy(entry->addr, *addr);
|
| mbed714 |
0:d616ece2d859
|
429
|
entry->next = local_hostlist_dynamic;
|
| mbed714 |
0:d616ece2d859
|
430
|
local_hostlist_dynamic = entry;
|
| mbed714 |
0:d616ece2d859
|
431
|
return ERR_OK;
|
| mbed714 |
0:d616ece2d859
|
432
|
}
|
| mbed714 |
0:d616ece2d859
|
433
|
#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC*/
|
| mbed714 |
0:d616ece2d859
|
434
|
#endif /* DNS_LOCAL_HOSTLIST */
|
| mbed714 |
0:d616ece2d859
|
435
|
|
| mbed714 |
0:d616ece2d859
|
436
|
/**
|
| mbed714 |
0:d616ece2d859
|
437
|
* Look up a hostname in the array of known hostnames.
|
| mbed714 |
0:d616ece2d859
|
438
|
*
|
| mbed714 |
0:d616ece2d859
|
439
|
* @note This function only looks in the internal array of known
|
| mbed714 |
0:d616ece2d859
|
440
|
* hostnames, it does not send out a query for the hostname if none
|
| mbed714 |
0:d616ece2d859
|
441
|
* was found. The function dns_enqueue() can be used to send a query
|
| mbed714 |
0:d616ece2d859
|
442
|
* for a hostname.
|
| mbed714 |
0:d616ece2d859
|
443
|
*
|
| mbed714 |
0:d616ece2d859
|
444
|
* @param name the hostname to look up
|
| mbed714 |
0:d616ece2d859
|
445
|
* @return the hostname's IP address, as u32_t (instead of ip_addr_t to
|
| mbed714 |
0:d616ece2d859
|
446
|
* better check for failure: != IPADDR_NONE) or IPADDR_NONE if the hostname
|
| mbed714 |
0:d616ece2d859
|
447
|
* was not found in the cached dns_table.
|
| mbed714 |
0:d616ece2d859
|
448
|
*/
|
| mbed714 |
0:d616ece2d859
|
449
|
static u32_t
|
| mbed714 |
0:d616ece2d859
|
450
|
dns_lookup(const char *name)
|
| mbed714 |
0:d616ece2d859
|
451
|
{
|
| mbed714 |
0:d616ece2d859
|
452
|
u8_t i;
|
| mbed714 |
0:d616ece2d859
|
453
|
#if DNS_LOCAL_HOSTLIST || defined(DNS_LOOKUP_LOCAL_EXTERN)
|
| mbed714 |
0:d616ece2d859
|
454
|
u32_t addr;
|
| mbed714 |
0:d616ece2d859
|
455
|
#endif /* DNS_LOCAL_HOSTLIST || defined(DNS_LOOKUP_LOCAL_EXTERN) */
|
| mbed714 |
0:d616ece2d859
|
456
|
#if DNS_LOCAL_HOSTLIST
|
| mbed714 |
0:d616ece2d859
|
457
|
if ((addr = dns_lookup_local(name)) != IPADDR_NONE) {
|
| mbed714 |
0:d616ece2d859
|
458
|
return addr;
|
| mbed714 |
0:d616ece2d859
|
459
|
}
|
| mbed714 |
0:d616ece2d859
|
460
|
#endif /* DNS_LOCAL_HOSTLIST */
|
| mbed714 |
0:d616ece2d859
|
461
|
#ifdef DNS_LOOKUP_LOCAL_EXTERN
|
| mbed714 |
0:d616ece2d859
|
462
|
if((addr = DNS_LOOKUP_LOCAL_EXTERN(name)) != IPADDR_NONE) {
|
| mbed714 |
0:d616ece2d859
|
463
|
return addr;
|
| mbed714 |
0:d616ece2d859
|
464
|
}
|
| mbed714 |
0:d616ece2d859
|
465
|
#endif /* DNS_LOOKUP_LOCAL_EXTERN */
|
| mbed714 |
0:d616ece2d859
|
466
|
|
| mbed714 |
0:d616ece2d859
|
467
|
/* Walk through name list, return entry if found. If not, return NULL. */
|
| mbed714 |
0:d616ece2d859
|
468
|
for (i = 0; i < DNS_TABLE_SIZE; ++i) {
|
| mbed714 |
0:d616ece2d859
|
469
|
if ((dns_table[i].state == DNS_STATE_DONE) &&
|
| mbed714 |
0:d616ece2d859
|
470
|
(strcmp(name, dns_table[i].name) == 0)) {
|
| mbed714 |
0:d616ece2d859
|
471
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_lookup: \"%s\": found = ", name));
|
| mbed714 |
0:d616ece2d859
|
472
|
ip_addr_debug_print(DNS_DEBUG, &(dns_table[i].ipaddr));
|
| mbed714 |
0:d616ece2d859
|
473
|
LWIP_DEBUGF(DNS_DEBUG, ("\n"));
|
| mbed714 |
0:d616ece2d859
|
474
|
return ip4_addr_get_u32(&dns_table[i].ipaddr);
|
| mbed714 |
0:d616ece2d859
|
475
|
}
|
| mbed714 |
0:d616ece2d859
|
476
|
}
|
| mbed714 |
0:d616ece2d859
|
477
|
|
| mbed714 |
0:d616ece2d859
|
478
|
return IPADDR_NONE;
|
| mbed714 |
0:d616ece2d859
|
479
|
}
|
| mbed714 |
0:d616ece2d859
|
480
|
|
| mbed714 |
0:d616ece2d859
|
481
|
#if DNS_DOES_NAME_CHECK
|
| mbed714 |
0:d616ece2d859
|
482
|
/**
|
| mbed714 |
0:d616ece2d859
|
483
|
* Compare the "dotted" name "query" with the encoded name "response"
|
| mbed714 |
0:d616ece2d859
|
484
|
* to make sure an answer from the DNS server matches the current dns_table
|
| mbed714 |
0:d616ece2d859
|
485
|
* entry (otherwise, answers might arrive late for hostname not on the list
|
| mbed714 |
0:d616ece2d859
|
486
|
* any more).
|
| mbed714 |
0:d616ece2d859
|
487
|
*
|
| mbed714 |
0:d616ece2d859
|
488
|
* @param query hostname (not encoded) from the dns_table
|
| mbed714 |
0:d616ece2d859
|
489
|
* @param response encoded hostname in the DNS response
|
| mbed714 |
0:d616ece2d859
|
490
|
* @return 0: names equal; 1: names differ
|
| mbed714 |
0:d616ece2d859
|
491
|
*/
|
| mbed714 |
0:d616ece2d859
|
492
|
static u8_t
|
| mbed714 |
0:d616ece2d859
|
493
|
dns_compare_name(unsigned char *query, unsigned char *response)
|
| mbed714 |
0:d616ece2d859
|
494
|
{
|
| mbed714 |
0:d616ece2d859
|
495
|
unsigned char n;
|
| mbed714 |
0:d616ece2d859
|
496
|
|
| mbed714 |
0:d616ece2d859
|
497
|
do {
|
| mbed714 |
0:d616ece2d859
|
498
|
n = *response++;
|
| mbed714 |
0:d616ece2d859
|
499
|
/** @see RFC 1035 - 4.1.4. Message compression */
|
| mbed714 |
0:d616ece2d859
|
500
|
if ((n & 0xc0) == 0xc0) {
|
| mbed714 |
0:d616ece2d859
|
501
|
/* Compressed name */
|
| mbed714 |
0:d616ece2d859
|
502
|
break;
|
| mbed714 |
0:d616ece2d859
|
503
|
} else {
|
| mbed714 |
0:d616ece2d859
|
504
|
/* Not compressed name */
|
| mbed714 |
0:d616ece2d859
|
505
|
while (n > 0) {
|
| mbed714 |
0:d616ece2d859
|
506
|
if ((*query) != (*response)) {
|
| mbed714 |
0:d616ece2d859
|
507
|
return 1;
|
| mbed714 |
0:d616ece2d859
|
508
|
}
|
| mbed714 |
0:d616ece2d859
|
509
|
++response;
|
| mbed714 |
0:d616ece2d859
|
510
|
++query;
|
| mbed714 |
0:d616ece2d859
|
511
|
--n;
|
| mbed714 |
0:d616ece2d859
|
512
|
};
|
| mbed714 |
0:d616ece2d859
|
513
|
++query;
|
| mbed714 |
0:d616ece2d859
|
514
|
}
|
| mbed714 |
0:d616ece2d859
|
515
|
} while (*response != 0);
|
| mbed714 |
0:d616ece2d859
|
516
|
|
| mbed714 |
0:d616ece2d859
|
517
|
return 0;
|
| mbed714 |
0:d616ece2d859
|
518
|
}
|
| mbed714 |
0:d616ece2d859
|
519
|
#endif /* DNS_DOES_NAME_CHECK */
|
| mbed714 |
0:d616ece2d859
|
520
|
|
| mbed714 |
0:d616ece2d859
|
521
|
/**
|
| mbed714 |
0:d616ece2d859
|
522
|
* Walk through a compact encoded DNS name and return the end of the name.
|
| mbed714 |
0:d616ece2d859
|
523
|
*
|
| mbed714 |
0:d616ece2d859
|
524
|
* @param query encoded DNS name in the DNS server response
|
| mbed714 |
0:d616ece2d859
|
525
|
* @return end of the name
|
| mbed714 |
0:d616ece2d859
|
526
|
*/
|
| mbed714 |
0:d616ece2d859
|
527
|
static unsigned char *
|
| mbed714 |
0:d616ece2d859
|
528
|
dns_parse_name(unsigned char *query)
|
| mbed714 |
0:d616ece2d859
|
529
|
{
|
| mbed714 |
0:d616ece2d859
|
530
|
unsigned char n;
|
| mbed714 |
0:d616ece2d859
|
531
|
|
| mbed714 |
0:d616ece2d859
|
532
|
do {
|
| mbed714 |
0:d616ece2d859
|
533
|
n = *query++;
|
| mbed714 |
0:d616ece2d859
|
534
|
/** @see RFC 1035 - 4.1.4. Message compression */
|
| mbed714 |
0:d616ece2d859
|
535
|
if ((n & 0xc0) == 0xc0) {
|
| mbed714 |
0:d616ece2d859
|
536
|
/* Compressed name */
|
| mbed714 |
0:d616ece2d859
|
537
|
break;
|
| mbed714 |
0:d616ece2d859
|
538
|
} else {
|
| mbed714 |
0:d616ece2d859
|
539
|
/* Not compressed name */
|
| mbed714 |
0:d616ece2d859
|
540
|
while (n > 0) {
|
| mbed714 |
0:d616ece2d859
|
541
|
++query;
|
| mbed714 |
0:d616ece2d859
|
542
|
--n;
|
| mbed714 |
0:d616ece2d859
|
543
|
};
|
| mbed714 |
0:d616ece2d859
|
544
|
}
|
| mbed714 |
0:d616ece2d859
|
545
|
} while (*query != 0);
|
| mbed714 |
0:d616ece2d859
|
546
|
|
| mbed714 |
0:d616ece2d859
|
547
|
return query + 1;
|
| mbed714 |
0:d616ece2d859
|
548
|
}
|
| mbed714 |
0:d616ece2d859
|
549
|
|
| mbed714 |
0:d616ece2d859
|
550
|
/**
|
| mbed714 |
0:d616ece2d859
|
551
|
* Send a DNS query packet.
|
| mbed714 |
0:d616ece2d859
|
552
|
*
|
| mbed714 |
0:d616ece2d859
|
553
|
* @param numdns index of the DNS server in the dns_servers table
|
| mbed714 |
0:d616ece2d859
|
554
|
* @param name hostname to query
|
| mbed714 |
0:d616ece2d859
|
555
|
* @param id index of the hostname in dns_table, used as transaction ID in the
|
| mbed714 |
0:d616ece2d859
|
556
|
* DNS query packet
|
| mbed714 |
0:d616ece2d859
|
557
|
* @return ERR_OK if packet is sent; an err_t indicating the problem otherwise
|
| mbed714 |
0:d616ece2d859
|
558
|
*/
|
| mbed714 |
0:d616ece2d859
|
559
|
static err_t
|
| mbed714 |
0:d616ece2d859
|
560
|
dns_send(u8_t numdns, const char* name, u8_t id)
|
| mbed714 |
0:d616ece2d859
|
561
|
{
|
| mbed714 |
0:d616ece2d859
|
562
|
err_t err;
|
| mbed714 |
0:d616ece2d859
|
563
|
struct dns_hdr *hdr;
|
| mbed714 |
0:d616ece2d859
|
564
|
struct dns_query qry;
|
| mbed714 |
0:d616ece2d859
|
565
|
struct pbuf *p;
|
| mbed714 |
0:d616ece2d859
|
566
|
char *query, *nptr;
|
| mbed714 |
0:d616ece2d859
|
567
|
const char *pHostname;
|
| mbed714 |
0:d616ece2d859
|
568
|
u8_t n;
|
| mbed714 |
0:d616ece2d859
|
569
|
|
| mbed714 |
0:d616ece2d859
|
570
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_send: dns_servers[%"U16_F"] \"%s\": request\n",
|
| mbed714 |
0:d616ece2d859
|
571
|
(u16_t)(numdns), name));
|
| mbed714 |
0:d616ece2d859
|
572
|
LWIP_ASSERT("dns server out of array", numdns < DNS_MAX_SERVERS);
|
| mbed714 |
0:d616ece2d859
|
573
|
LWIP_ASSERT("dns server has no IP address set", !ip_addr_isany(&dns_servers[numdns]));
|
| mbed714 |
0:d616ece2d859
|
574
|
|
| mbed714 |
0:d616ece2d859
|
575
|
/* if here, we have either a new query or a retry on a previous query to process */
|
| mbed714 |
0:d616ece2d859
|
576
|
p = pbuf_alloc(PBUF_TRANSPORT, SIZEOF_DNS_HDR + DNS_MAX_NAME_LENGTH +
|
| mbed714 |
0:d616ece2d859
|
577
|
SIZEOF_DNS_QUERY, PBUF_RAM);
|
| mbed714 |
0:d616ece2d859
|
578
|
if (p != NULL) {
|
| mbed714 |
0:d616ece2d859
|
579
|
LWIP_ASSERT("pbuf must be in one piece", p->next == NULL);
|
| mbed714 |
0:d616ece2d859
|
580
|
/* fill dns header */
|
| mbed714 |
0:d616ece2d859
|
581
|
hdr = (struct dns_hdr*)p->payload;
|
| mbed714 |
0:d616ece2d859
|
582
|
memset(hdr, 0, SIZEOF_DNS_HDR);
|
| mbed714 |
0:d616ece2d859
|
583
|
hdr->id = htons(id);
|
| mbed714 |
0:d616ece2d859
|
584
|
hdr->flags1 = DNS_FLAG1_RD;
|
| mbed714 |
0:d616ece2d859
|
585
|
hdr->numquestions = PP_HTONS(1);
|
| mbed714 |
0:d616ece2d859
|
586
|
query = (char*)hdr + SIZEOF_DNS_HDR;
|
| mbed714 |
0:d616ece2d859
|
587
|
pHostname = name;
|
| mbed714 |
0:d616ece2d859
|
588
|
--pHostname;
|
| mbed714 |
0:d616ece2d859
|
589
|
|
| mbed714 |
0:d616ece2d859
|
590
|
/* convert hostname into suitable query format. */
|
| mbed714 |
0:d616ece2d859
|
591
|
do {
|
| mbed714 |
0:d616ece2d859
|
592
|
++pHostname;
|
| mbed714 |
0:d616ece2d859
|
593
|
nptr = query;
|
| mbed714 |
0:d616ece2d859
|
594
|
++query;
|
| mbed714 |
0:d616ece2d859
|
595
|
for(n = 0; *pHostname != '.' && *pHostname != 0; ++pHostname) {
|
| mbed714 |
0:d616ece2d859
|
596
|
*query = *pHostname;
|
| mbed714 |
0:d616ece2d859
|
597
|
++query;
|
| mbed714 |
0:d616ece2d859
|
598
|
++n;
|
| mbed714 |
0:d616ece2d859
|
599
|
}
|
| mbed714 |
0:d616ece2d859
|
600
|
*nptr = n;
|
| mbed714 |
0:d616ece2d859
|
601
|
} while(*pHostname != 0);
|
| mbed714 |
0:d616ece2d859
|
602
|
*query++='\0';
|
| mbed714 |
0:d616ece2d859
|
603
|
|
| mbed714 |
0:d616ece2d859
|
604
|
/* fill dns query */
|
| mbed714 |
0:d616ece2d859
|
605
|
qry.type = PP_HTONS(DNS_RRTYPE_A);
|
| mbed714 |
0:d616ece2d859
|
606
|
qry.cls = PP_HTONS(DNS_RRCLASS_IN);
|
| mbed714 |
0:d616ece2d859
|
607
|
SMEMCPY(query, &qry, SIZEOF_DNS_QUERY);
|
| mbed714 |
0:d616ece2d859
|
608
|
|
| mbed714 |
0:d616ece2d859
|
609
|
/* resize pbuf to the exact dns query */
|
| mbed714 |
0:d616ece2d859
|
610
|
pbuf_realloc(p, (u16_t)((query + SIZEOF_DNS_QUERY) - ((char*)(p->payload))));
|
| mbed714 |
0:d616ece2d859
|
611
|
|
| mbed714 |
0:d616ece2d859
|
612
|
/* connect to the server for faster receiving */
|
| mbed714 |
0:d616ece2d859
|
613
|
udp_connect(dns_pcb, &dns_servers[numdns], DNS_SERVER_PORT);
|
| mbed714 |
0:d616ece2d859
|
614
|
/* send dns packet */
|
| mbed714 |
0:d616ece2d859
|
615
|
err = udp_sendto(dns_pcb, p, &dns_servers[numdns], DNS_SERVER_PORT);
|
| mbed714 |
0:d616ece2d859
|
616
|
|
| mbed714 |
0:d616ece2d859
|
617
|
/* free pbuf */
|
| mbed714 |
0:d616ece2d859
|
618
|
pbuf_free(p);
|
| mbed714 |
0:d616ece2d859
|
619
|
} else {
|
| mbed714 |
0:d616ece2d859
|
620
|
err = ERR_MEM;
|
| mbed714 |
0:d616ece2d859
|
621
|
}
|
| mbed714 |
0:d616ece2d859
|
622
|
|
| mbed714 |
0:d616ece2d859
|
623
|
return err;
|
| mbed714 |
0:d616ece2d859
|
624
|
}
|
| mbed714 |
0:d616ece2d859
|
625
|
|
| mbed714 |
0:d616ece2d859
|
626
|
/**
|
| mbed714 |
0:d616ece2d859
|
627
|
* dns_check_entry() - see if pEntry has not yet been queried and, if so, sends out a query.
|
| mbed714 |
0:d616ece2d859
|
628
|
* Check an entry in the dns_table:
|
| mbed714 |
0:d616ece2d859
|
629
|
* - send out query for new entries
|
| mbed714 |
0:d616ece2d859
|
630
|
* - retry old pending entries on timeout (also with different servers)
|
| mbed714 |
0:d616ece2d859
|
631
|
* - remove completed entries from the table if their TTL has expired
|
| mbed714 |
0:d616ece2d859
|
632
|
*
|
| mbed714 |
0:d616ece2d859
|
633
|
* @param i index of the dns_table entry to check
|
| mbed714 |
0:d616ece2d859
|
634
|
*/
|
| mbed714 |
0:d616ece2d859
|
635
|
static void
|
| mbed714 |
0:d616ece2d859
|
636
|
dns_check_entry(u8_t i)
|
| mbed714 |
0:d616ece2d859
|
637
|
{
|
| mbed714 |
0:d616ece2d859
|
638
|
err_t err;
|
| mbed714 |
0:d616ece2d859
|
639
|
struct dns_table_entry *pEntry = &dns_table[i];
|
| mbed714 |
0:d616ece2d859
|
640
|
|
| mbed714 |
0:d616ece2d859
|
641
|
LWIP_ASSERT("array index out of bounds", i < DNS_TABLE_SIZE);
|
| mbed714 |
0:d616ece2d859
|
642
|
|
| mbed714 |
0:d616ece2d859
|
643
|
switch(pEntry->state) {
|
| mbed714 |
0:d616ece2d859
|
644
|
|
| mbed714 |
0:d616ece2d859
|
645
|
case DNS_STATE_NEW: {
|
| mbed714 |
0:d616ece2d859
|
646
|
/* initialize new entry */
|
| mbed714 |
0:d616ece2d859
|
647
|
pEntry->state = DNS_STATE_ASKING;
|
| mbed714 |
0:d616ece2d859
|
648
|
pEntry->numdns = 0;
|
| mbed714 |
0:d616ece2d859
|
649
|
pEntry->tmr = 1;
|
| mbed714 |
0:d616ece2d859
|
650
|
pEntry->retries = 0;
|
| mbed714 |
0:d616ece2d859
|
651
|
|
| mbed714 |
0:d616ece2d859
|
652
|
/* send DNS packet for this entry */
|
| mbed714 |
0:d616ece2d859
|
653
|
err = dns_send(pEntry->numdns, pEntry->name, i);
|
| mbed714 |
0:d616ece2d859
|
654
|
if (err != ERR_OK) {
|
| mbed714 |
0:d616ece2d859
|
655
|
LWIP_DEBUGF(DNS_DEBUG | LWIP_DBG_LEVEL_WARNING,
|
| mbed714 |
0:d616ece2d859
|
656
|
("dns_send returned error: %d\n", err)); //FIX DG, lwip_strerr is part of lwip/api
|
| mbed714 |
0:d616ece2d859
|
657
|
}
|
| mbed714 |
0:d616ece2d859
|
658
|
break;
|
| mbed714 |
0:d616ece2d859
|
659
|
}
|
| mbed714 |
0:d616ece2d859
|
660
|
|
| mbed714 |
0:d616ece2d859
|
661
|
case DNS_STATE_ASKING: {
|
| mbed714 |
0:d616ece2d859
|
662
|
if (--pEntry->tmr == 0) {
|
| mbed714 |
0:d616ece2d859
|
663
|
if (++pEntry->retries == DNS_MAX_RETRIES) {
|
| mbed714 |
0:d616ece2d859
|
664
|
if ((pEntry->numdns+1<DNS_MAX_SERVERS) && !ip_addr_isany(&dns_servers[pEntry->numdns+1])) {
|
| mbed714 |
0:d616ece2d859
|
665
|
/* change of server */
|
| mbed714 |
0:d616ece2d859
|
666
|
pEntry->numdns++;
|
| mbed714 |
0:d616ece2d859
|
667
|
pEntry->tmr = 1;
|
| mbed714 |
0:d616ece2d859
|
668
|
pEntry->retries = 0;
|
| mbed714 |
0:d616ece2d859
|
669
|
break;
|
| mbed714 |
0:d616ece2d859
|
670
|
} else {
|
| mbed714 |
0:d616ece2d859
|
671
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_check_entry: \"%s\": timeout\n", pEntry->name));
|
| mbed714 |
0:d616ece2d859
|
672
|
/* call specified callback function if provided */
|
| mbed714 |
0:d616ece2d859
|
673
|
if (pEntry->found)
|
| mbed714 |
0:d616ece2d859
|
674
|
(*pEntry->found)(pEntry->name, NULL, pEntry->arg);
|
| mbed714 |
0:d616ece2d859
|
675
|
/* flush this entry */
|
| mbed714 |
0:d616ece2d859
|
676
|
pEntry->state = DNS_STATE_UNUSED;
|
| mbed714 |
0:d616ece2d859
|
677
|
pEntry->found = NULL;
|
| mbed714 |
0:d616ece2d859
|
678
|
break;
|
| mbed714 |
0:d616ece2d859
|
679
|
}
|
| mbed714 |
0:d616ece2d859
|
680
|
}
|
| mbed714 |
0:d616ece2d859
|
681
|
|
| mbed714 |
0:d616ece2d859
|
682
|
/* wait longer for the next retry */
|
| mbed714 |
0:d616ece2d859
|
683
|
pEntry->tmr = pEntry->retries;
|
| mbed714 |
0:d616ece2d859
|
684
|
|
| mbed714 |
0:d616ece2d859
|
685
|
/* send DNS packet for this entry */
|
| mbed714 |
0:d616ece2d859
|
686
|
err = dns_send(pEntry->numdns, pEntry->name, i);
|
| mbed714 |
0:d616ece2d859
|
687
|
if (err != ERR_OK) {
|
| mbed714 |
0:d616ece2d859
|
688
|
LWIP_DEBUGF(DNS_DEBUG | LWIP_DBG_LEVEL_WARNING,
|
| mbed714 |
0:d616ece2d859
|
689
|
("dns_send returned error: %d\n", err)); //FIX DG, lwip_strerr is part of lwip/api
|
| mbed714 |
0:d616ece2d859
|
690
|
}
|
| mbed714 |
0:d616ece2d859
|
691
|
}
|
| mbed714 |
0:d616ece2d859
|
692
|
break;
|
| mbed714 |
0:d616ece2d859
|
693
|
}
|
| mbed714 |
0:d616ece2d859
|
694
|
|
| mbed714 |
0:d616ece2d859
|
695
|
case DNS_STATE_DONE: {
|
| mbed714 |
0:d616ece2d859
|
696
|
/* if the time to live is nul */
|
| mbed714 |
0:d616ece2d859
|
697
|
if (--pEntry->ttl == 0) {
|
| mbed714 |
0:d616ece2d859
|
698
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_check_entry: \"%s\": flush\n", pEntry->name));
|
| mbed714 |
0:d616ece2d859
|
699
|
/* flush this entry */
|
| mbed714 |
0:d616ece2d859
|
700
|
pEntry->state = DNS_STATE_UNUSED;
|
| mbed714 |
0:d616ece2d859
|
701
|
pEntry->found = NULL;
|
| mbed714 |
0:d616ece2d859
|
702
|
}
|
| mbed714 |
0:d616ece2d859
|
703
|
break;
|
| mbed714 |
0:d616ece2d859
|
704
|
}
|
| mbed714 |
0:d616ece2d859
|
705
|
case DNS_STATE_UNUSED:
|
| mbed714 |
0:d616ece2d859
|
706
|
/* nothing to do */
|
| mbed714 |
0:d616ece2d859
|
707
|
break;
|
| mbed714 |
0:d616ece2d859
|
708
|
default:
|
| mbed714 |
0:d616ece2d859
|
709
|
LWIP_ASSERT("unknown dns_table entry state:", 0);
|
| mbed714 |
0:d616ece2d859
|
710
|
break;
|
| mbed714 |
0:d616ece2d859
|
711
|
}
|
| mbed714 |
0:d616ece2d859
|
712
|
}
|
| mbed714 |
0:d616ece2d859
|
713
|
|
| mbed714 |
0:d616ece2d859
|
714
|
/**
|
| mbed714 |
0:d616ece2d859
|
715
|
* Call dns_check_entry for each entry in dns_table - check all entries.
|
| mbed714 |
0:d616ece2d859
|
716
|
*/
|
| mbed714 |
0:d616ece2d859
|
717
|
static void
|
| mbed714 |
0:d616ece2d859
|
718
|
dns_check_entries(void)
|
| mbed714 |
0:d616ece2d859
|
719
|
{
|
| mbed714 |
0:d616ece2d859
|
720
|
u8_t i;
|
| mbed714 |
0:d616ece2d859
|
721
|
|
| mbed714 |
0:d616ece2d859
|
722
|
for (i = 0; i < DNS_TABLE_SIZE; ++i) {
|
| mbed714 |
0:d616ece2d859
|
723
|
dns_check_entry(i);
|
| mbed714 |
0:d616ece2d859
|
724
|
}
|
| mbed714 |
0:d616ece2d859
|
725
|
}
|
| mbed714 |
0:d616ece2d859
|
726
|
|
| mbed714 |
0:d616ece2d859
|
727
|
/**
|
| mbed714 |
0:d616ece2d859
|
728
|
* Receive input function for DNS response packets arriving for the dns UDP pcb.
|
| mbed714 |
0:d616ece2d859
|
729
|
*
|
| mbed714 |
0:d616ece2d859
|
730
|
* @params see udp.h
|
| mbed714 |
0:d616ece2d859
|
731
|
*/
|
| mbed714 |
0:d616ece2d859
|
732
|
static void
|
| mbed714 |
0:d616ece2d859
|
733
|
dns_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port)
|
| mbed714 |
0:d616ece2d859
|
734
|
{
|
| mbed714 |
0:d616ece2d859
|
735
|
u16_t i;
|
| mbed714 |
0:d616ece2d859
|
736
|
char *pHostname;
|
| mbed714 |
0:d616ece2d859
|
737
|
struct dns_hdr *hdr;
|
| mbed714 |
0:d616ece2d859
|
738
|
struct dns_answer ans;
|
| mbed714 |
0:d616ece2d859
|
739
|
struct dns_table_entry *pEntry;
|
| mbed714 |
0:d616ece2d859
|
740
|
u16_t nquestions, nanswers;
|
| mbed714 |
0:d616ece2d859
|
741
|
|
| mbed714 |
0:d616ece2d859
|
742
|
LWIP_UNUSED_ARG(arg);
|
| mbed714 |
0:d616ece2d859
|
743
|
LWIP_UNUSED_ARG(pcb);
|
| mbed714 |
0:d616ece2d859
|
744
|
LWIP_UNUSED_ARG(addr);
|
| mbed714 |
0:d616ece2d859
|
745
|
LWIP_UNUSED_ARG(port);
|
| mbed714 |
0:d616ece2d859
|
746
|
|
| mbed714 |
0:d616ece2d859
|
747
|
/* is the dns message too big ? */
|
| mbed714 |
0:d616ece2d859
|
748
|
if (p->tot_len > DNS_MSG_SIZE) {
|
| mbed714 |
0:d616ece2d859
|
749
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: pbuf too big\n"));
|
| mbed714 |
0:d616ece2d859
|
750
|
/* free pbuf and return */
|
| mbed714 |
0:d616ece2d859
|
751
|
goto memerr;
|
| mbed714 |
0:d616ece2d859
|
752
|
}
|
| mbed714 |
0:d616ece2d859
|
753
|
|
| mbed714 |
0:d616ece2d859
|
754
|
/* is the dns message big enough ? */
|
| mbed714 |
0:d616ece2d859
|
755
|
if (p->tot_len < (SIZEOF_DNS_HDR + SIZEOF_DNS_QUERY + SIZEOF_DNS_ANSWER)) {
|
| mbed714 |
0:d616ece2d859
|
756
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: pbuf too small\n"));
|
| mbed714 |
0:d616ece2d859
|
757
|
/* free pbuf and return */
|
| mbed714 |
0:d616ece2d859
|
758
|
goto memerr;
|
| mbed714 |
0:d616ece2d859
|
759
|
}
|
| mbed714 |
0:d616ece2d859
|
760
|
|
| mbed714 |
0:d616ece2d859
|
761
|
/* copy dns payload inside static buffer for processing */
|
| mbed714 |
0:d616ece2d859
|
762
|
if (pbuf_copy_partial(p, dns_payload, p->tot_len, 0) == p->tot_len) {
|
| mbed714 |
0:d616ece2d859
|
763
|
/* The ID in the DNS header should be our entry into the name table. */
|
| mbed714 |
0:d616ece2d859
|
764
|
hdr = (struct dns_hdr*)dns_payload;
|
| mbed714 |
0:d616ece2d859
|
765
|
i = htons(hdr->id);
|
| mbed714 |
0:d616ece2d859
|
766
|
if (i < DNS_TABLE_SIZE) {
|
| mbed714 |
0:d616ece2d859
|
767
|
pEntry = &dns_table[i];
|
| mbed714 |
0:d616ece2d859
|
768
|
if(pEntry->state == DNS_STATE_ASKING) {
|
| mbed714 |
0:d616ece2d859
|
769
|
/* This entry is now completed. */
|
| mbed714 |
0:d616ece2d859
|
770
|
pEntry->state = DNS_STATE_DONE;
|
| mbed714 |
0:d616ece2d859
|
771
|
pEntry->err = hdr->flags2 & DNS_FLAG2_ERR_MASK;
|
| mbed714 |
0:d616ece2d859
|
772
|
|
| mbed714 |
0:d616ece2d859
|
773
|
/* We only care about the question(s) and the answers. The authrr
|
| mbed714 |
0:d616ece2d859
|
774
|
and the extrarr are simply discarded. */
|
| mbed714 |
0:d616ece2d859
|
775
|
nquestions = htons(hdr->numquestions);
|
| mbed714 |
0:d616ece2d859
|
776
|
nanswers = htons(hdr->numanswers);
|
| mbed714 |
0:d616ece2d859
|
777
|
|
| mbed714 |
0:d616ece2d859
|
778
|
/* Check for error. If so, call callback to inform. */
|
| mbed714 |
0:d616ece2d859
|
779
|
if (((hdr->flags1 & DNS_FLAG1_RESPONSE) == 0) || (pEntry->err != 0) || (nquestions != 1)) {
|
| mbed714 |
0:d616ece2d859
|
780
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in flags\n", pEntry->name));
|
| mbed714 |
0:d616ece2d859
|
781
|
/* call callback to indicate error, clean up memory and return */
|
| mbed714 |
0:d616ece2d859
|
782
|
goto responseerr;
|
| mbed714 |
0:d616ece2d859
|
783
|
}
|
| mbed714 |
0:d616ece2d859
|
784
|
|
| mbed714 |
0:d616ece2d859
|
785
|
#if DNS_DOES_NAME_CHECK
|
| mbed714 |
0:d616ece2d859
|
786
|
/* Check if the name in the "question" part match with the name in the entry. */
|
| mbed714 |
0:d616ece2d859
|
787
|
if (dns_compare_name((unsigned char *)(pEntry->name), (unsigned char *)dns_payload + SIZEOF_DNS_HDR) != 0) {
|
| mbed714 |
0:d616ece2d859
|
788
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": response not match to query\n", pEntry->name));
|
| mbed714 |
0:d616ece2d859
|
789
|
/* call callback to indicate error, clean up memory and return */
|
| mbed714 |
0:d616ece2d859
|
790
|
goto responseerr;
|
| mbed714 |
0:d616ece2d859
|
791
|
}
|
| mbed714 |
0:d616ece2d859
|
792
|
#endif /* DNS_DOES_NAME_CHECK */
|
| mbed714 |
0:d616ece2d859
|
793
|
|
| mbed714 |
0:d616ece2d859
|
794
|
/* Skip the name in the "question" part */
|
| mbed714 |
0:d616ece2d859
|
795
|
pHostname = (char *) dns_parse_name((unsigned char *)dns_payload + SIZEOF_DNS_HDR) + SIZEOF_DNS_QUERY;
|
| mbed714 |
0:d616ece2d859
|
796
|
|
| mbed714 |
0:d616ece2d859
|
797
|
while (nanswers > 0) {
|
| mbed714 |
0:d616ece2d859
|
798
|
/* skip answer resource record's host name */
|
| mbed714 |
0:d616ece2d859
|
799
|
pHostname = (char *) dns_parse_name((unsigned char *)pHostname);
|
| mbed714 |
0:d616ece2d859
|
800
|
|
| mbed714 |
0:d616ece2d859
|
801
|
/* Check for IP address type and Internet class. Others are discarded. */
|
| mbed714 |
0:d616ece2d859
|
802
|
SMEMCPY(&ans, pHostname, SIZEOF_DNS_ANSWER);
|
| mbed714 |
0:d616ece2d859
|
803
|
if((ans.type == PP_HTONS(DNS_RRTYPE_A)) && (ans.cls == PP_HTONS(DNS_RRCLASS_IN)) &&
|
| mbed714 |
0:d616ece2d859
|
804
|
(ans.len == PP_HTONS(sizeof(ip_addr_t))) ) {
|
| mbed714 |
0:d616ece2d859
|
805
|
/* read the answer resource record's TTL, and maximize it if needed */
|
| mbed714 |
0:d616ece2d859
|
806
|
pEntry->ttl = ntohl(ans.ttl);
|
| mbed714 |
0:d616ece2d859
|
807
|
if (pEntry->ttl > DNS_MAX_TTL) {
|
| mbed714 |
0:d616ece2d859
|
808
|
pEntry->ttl = DNS_MAX_TTL;
|
| mbed714 |
0:d616ece2d859
|
809
|
}
|
| mbed714 |
0:d616ece2d859
|
810
|
/* read the IP address after answer resource record's header */
|
| mbed714 |
0:d616ece2d859
|
811
|
SMEMCPY(&(pEntry->ipaddr), (pHostname+SIZEOF_DNS_ANSWER), sizeof(ip_addr_t));
|
| mbed714 |
0:d616ece2d859
|
812
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": response = ", pEntry->name));
|
| mbed714 |
0:d616ece2d859
|
813
|
ip_addr_debug_print(DNS_DEBUG, (&(pEntry->ipaddr)));
|
| mbed714 |
0:d616ece2d859
|
814
|
LWIP_DEBUGF(DNS_DEBUG, ("\n"));
|
| mbed714 |
0:d616ece2d859
|
815
|
/* call specified callback function if provided */
|
| mbed714 |
0:d616ece2d859
|
816
|
if (pEntry->found) {
|
| mbed714 |
0:d616ece2d859
|
817
|
(*pEntry->found)(pEntry->name, &pEntry->ipaddr, pEntry->arg);
|
| mbed714 |
0:d616ece2d859
|
818
|
}
|
| mbed714 |
0:d616ece2d859
|
819
|
/* deallocate memory and return */
|
| mbed714 |
0:d616ece2d859
|
820
|
goto memerr;
|
| mbed714 |
0:d616ece2d859
|
821
|
} else {
|
| mbed714 |
0:d616ece2d859
|
822
|
pHostname = pHostname + SIZEOF_DNS_ANSWER + htons(ans.len);
|
| mbed714 |
0:d616ece2d859
|
823
|
}
|
| mbed714 |
0:d616ece2d859
|
824
|
--nanswers;
|
| mbed714 |
0:d616ece2d859
|
825
|
}
|
| mbed714 |
0:d616ece2d859
|
826
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in response\n", pEntry->name));
|
| mbed714 |
0:d616ece2d859
|
827
|
/* call callback to indicate error, clean up memory and return */
|
| mbed714 |
0:d616ece2d859
|
828
|
goto responseerr;
|
| mbed714 |
0:d616ece2d859
|
829
|
}
|
| mbed714 |
0:d616ece2d859
|
830
|
}
|
| mbed714 |
0:d616ece2d859
|
831
|
}
|
| mbed714 |
0:d616ece2d859
|
832
|
|
| mbed714 |
0:d616ece2d859
|
833
|
/* deallocate memory and return */
|
| mbed714 |
0:d616ece2d859
|
834
|
goto memerr;
|
| mbed714 |
0:d616ece2d859
|
835
|
|
| mbed714 |
0:d616ece2d859
|
836
|
responseerr:
|
| mbed714 |
0:d616ece2d859
|
837
|
/* ERROR: call specified callback function with NULL as name to indicate an error */
|
| mbed714 |
0:d616ece2d859
|
838
|
if (pEntry->found) {
|
| mbed714 |
0:d616ece2d859
|
839
|
(*pEntry->found)(pEntry->name, NULL, pEntry->arg);
|
| mbed714 |
0:d616ece2d859
|
840
|
}
|
| mbed714 |
0:d616ece2d859
|
841
|
/* flush this entry */
|
| mbed714 |
0:d616ece2d859
|
842
|
pEntry->state = DNS_STATE_UNUSED;
|
| mbed714 |
0:d616ece2d859
|
843
|
pEntry->found = NULL;
|
| mbed714 |
0:d616ece2d859
|
844
|
|
| mbed714 |
0:d616ece2d859
|
845
|
memerr:
|
| mbed714 |
0:d616ece2d859
|
846
|
/* free pbuf */
|
| mbed714 |
0:d616ece2d859
|
847
|
pbuf_free(p);
|
| mbed714 |
0:d616ece2d859
|
848
|
return;
|
| mbed714 |
0:d616ece2d859
|
849
|
}
|
| mbed714 |
0:d616ece2d859
|
850
|
|
| mbed714 |
0:d616ece2d859
|
851
|
/**
|
| mbed714 |
0:d616ece2d859
|
852
|
* Queues a new hostname to resolve and sends out a DNS query for that hostname
|
| mbed714 |
0:d616ece2d859
|
853
|
*
|
| mbed714 |
0:d616ece2d859
|
854
|
* @param name the hostname that is to be queried
|
| mbed714 |
0:d616ece2d859
|
855
|
* @param found a callback founction to be called on success, failure or timeout
|
| mbed714 |
0:d616ece2d859
|
856
|
* @param callback_arg argument to pass to the callback function
|
| mbed714 |
0:d616ece2d859
|
857
|
* @return @return a err_t return code.
|
| mbed714 |
0:d616ece2d859
|
858
|
*/
|
| mbed714 |
0:d616ece2d859
|
859
|
static err_t
|
| mbed714 |
0:d616ece2d859
|
860
|
dns_enqueue(const char *name, dns_found_callback found, void *callback_arg)
|
| mbed714 |
0:d616ece2d859
|
861
|
{
|
| mbed714 |
0:d616ece2d859
|
862
|
u8_t i;
|
| mbed714 |
0:d616ece2d859
|
863
|
u8_t lseq, lseqi;
|
| mbed714 |
0:d616ece2d859
|
864
|
struct dns_table_entry *pEntry = NULL;
|
| mbed714 |
0:d616ece2d859
|
865
|
size_t namelen;
|
| mbed714 |
0:d616ece2d859
|
866
|
|
| mbed714 |
0:d616ece2d859
|
867
|
/* search an unused entry, or the oldest one */
|
| mbed714 |
0:d616ece2d859
|
868
|
lseq = lseqi = 0;
|
| mbed714 |
0:d616ece2d859
|
869
|
for (i = 0; i < DNS_TABLE_SIZE; ++i) {
|
| mbed714 |
0:d616ece2d859
|
870
|
pEntry = &dns_table[i];
|
| mbed714 |
0:d616ece2d859
|
871
|
/* is it an unused entry ? */
|
| mbed714 |
0:d616ece2d859
|
872
|
if (pEntry->state == DNS_STATE_UNUSED)
|
| mbed714 |
0:d616ece2d859
|
873
|
break;
|
| mbed714 |
0:d616ece2d859
|
874
|
|
| mbed714 |
0:d616ece2d859
|
875
|
/* check if this is the oldest completed entry */
|
| mbed714 |
0:d616ece2d859
|
876
|
if (pEntry->state == DNS_STATE_DONE) {
|
| mbed714 |
0:d616ece2d859
|
877
|
if ((dns_seqno - pEntry->seqno) > lseq) {
|
| mbed714 |
0:d616ece2d859
|
878
|
lseq = dns_seqno - pEntry->seqno;
|
| mbed714 |
0:d616ece2d859
|
879
|
lseqi = i;
|
| mbed714 |
0:d616ece2d859
|
880
|
}
|
| mbed714 |
0:d616ece2d859
|
881
|
}
|
| mbed714 |
0:d616ece2d859
|
882
|
}
|
| mbed714 |
0:d616ece2d859
|
883
|
|
| mbed714 |
0:d616ece2d859
|
884
|
/* if we don't have found an unused entry, use the oldest completed one */
|
| mbed714 |
0:d616ece2d859
|
885
|
if (i == DNS_TABLE_SIZE) {
|
| mbed714 |
0:d616ece2d859
|
886
|
if ((lseqi >= DNS_TABLE_SIZE) || (dns_table[lseqi].state != DNS_STATE_DONE)) {
|
| mbed714 |
0:d616ece2d859
|
887
|
/* no entry can't be used now, table is full */
|
| mbed714 |
0:d616ece2d859
|
888
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_enqueue: \"%s\": DNS entries table is full\n", name));
|
| mbed714 |
0:d616ece2d859
|
889
|
return ERR_MEM;
|
| mbed714 |
0:d616ece2d859
|
890
|
} else {
|
| mbed714 |
0:d616ece2d859
|
891
|
/* use the oldest completed one */
|
| mbed714 |
0:d616ece2d859
|
892
|
i = lseqi;
|
| mbed714 |
0:d616ece2d859
|
893
|
pEntry = &dns_table[i];
|
| mbed714 |
0:d616ece2d859
|
894
|
}
|
| mbed714 |
0:d616ece2d859
|
895
|
}
|
| mbed714 |
0:d616ece2d859
|
896
|
|
| mbed714 |
0:d616ece2d859
|
897
|
/* use this entry */
|
| mbed714 |
0:d616ece2d859
|
898
|
LWIP_DEBUGF(DNS_DEBUG, ("dns_enqueue: \"%s\": use DNS entry %"U16_F"\n", name, (u16_t)(i)));
|
| mbed714 |
0:d616ece2d859
|
899
|
|
| mbed714 |
0:d616ece2d859
|
900
|
/* fill the entry */
|
| mbed714 |
0:d616ece2d859
|
901
|
pEntry->state = DNS_STATE_NEW;
|
| mbed714 |
0:d616ece2d859
|
902
|
pEntry->seqno = dns_seqno++;
|
| mbed714 |
0:d616ece2d859
|
903
|
pEntry->found = found;
|
| mbed714 |
0:d616ece2d859
|
904
|
pEntry->arg = callback_arg;
|
| mbed714 |
0:d616ece2d859
|
905
|
namelen = LWIP_MIN(strlen(name), DNS_MAX_NAME_LENGTH-1);
|
| mbed714 |
0:d616ece2d859
|
906
|
MEMCPY(pEntry->name, name, namelen);
|
| mbed714 |
0:d616ece2d859
|
907
|
pEntry->name[namelen] = 0;
|
| mbed714 |
0:d616ece2d859
|
908
|
|
| mbed714 |
0:d616ece2d859
|
909
|
/* force to send query without waiting timer */
|
| mbed714 |
0:d616ece2d859
|
910
|
dns_check_entry(i);
|
| mbed714 |
0:d616ece2d859
|
911
|
|
| mbed714 |
0:d616ece2d859
|
912
|
/* dns query is enqueued */
|
| mbed714 |
0:d616ece2d859
|
913
|
return ERR_INPROGRESS;
|
| mbed714 |
0:d616ece2d859
|
914
|
}
|
| mbed714 |
0:d616ece2d859
|
915
|
|
| mbed714 |
0:d616ece2d859
|
916
|
/**
|
| mbed714 |
0:d616ece2d859
|
917
|
* Resolve a hostname (string) into an IP address.
|
| mbed714 |
0:d616ece2d859
|
918
|
* NON-BLOCKING callback version for use with raw API!!!
|
| mbed714 |
0:d616ece2d859
|
919
|
*
|
| mbed714 |
0:d616ece2d859
|
920
|
* Returns immediately with one of err_t return codes:
|
| mbed714 |
0:d616ece2d859
|
921
|
* - ERR_OK if hostname is a valid IP address string or the host
|
| mbed714 |
0:d616ece2d859
|
922
|
* name is already in the local names table.
|
| mbed714 |
0:d616ece2d859
|
923
|
* - ERR_INPROGRESS enqueue a request to be sent to the DNS server
|
| mbed714 |
0:d616ece2d859
|
924
|
* for resolution if no errors are present.
|
| mbed714 |
0:d616ece2d859
|
925
|
*
|
| mbed714 |
0:d616ece2d859
|
926
|
* @param hostname the hostname that is to be queried
|
| mbed714 |
0:d616ece2d859
|
927
|
* @param addr pointer to a ip_addr_t where to store the address if it is already
|
| mbed714 |
0:d616ece2d859
|
928
|
* cached in the dns_table (only valid if ERR_OK is returned!)
|
| mbed714 |
0:d616ece2d859
|
929
|
* @param found a callback function to be called on success, failure or timeout (only if
|
| mbed714 |
0:d616ece2d859
|
930
|
* ERR_INPROGRESS is returned!)
|
| mbed714 |
0:d616ece2d859
|
931
|
* @param callback_arg argument to pass to the callback function
|
| mbed714 |
0:d616ece2d859
|
932
|
* @return a err_t return code.
|
| mbed714 |
0:d616ece2d859
|
933
|
*/
|
| mbed714 |
0:d616ece2d859
|
934
|
err_t
|
| mbed714 |
0:d616ece2d859
|
935
|
dns_gethostbyname(const char *hostname, ip_addr_t *addr, dns_found_callback found,
|
| mbed714 |
0:d616ece2d859
|
936
|
void *callback_arg)
|
| mbed714 |
0:d616ece2d859
|
937
|
{
|
| mbed714 |
0:d616ece2d859
|
938
|
u32_t ipaddr;
|
| mbed714 |
0:d616ece2d859
|
939
|
/* not initialized or no valid server yet, or invalid addr pointer
|
| mbed714 |
0:d616ece2d859
|
940
|
* or invalid hostname or invalid hostname length */
|
| mbed714 |
0:d616ece2d859
|
941
|
if ((dns_pcb == NULL) || (addr == NULL) ||
|
| mbed714 |
0:d616ece2d859
|
942
|
(!hostname) || (!hostname[0]) ||
|
| mbed714 |
0:d616ece2d859
|
943
|
(strlen(hostname) >= DNS_MAX_NAME_LENGTH)) {
|
| mbed714 |
0:d616ece2d859
|
944
|
return ERR_VAL;
|
| mbed714 |
0:d616ece2d859
|
945
|
}
|
| mbed714 |
0:d616ece2d859
|
946
|
|
| mbed714 |
0:d616ece2d859
|
947
|
#if LWIP_HAVE_LOOPIF
|
| mbed714 |
0:d616ece2d859
|
948
|
if (strcmp(hostname, "localhost")==0) {
|
| mbed714 |
0:d616ece2d859
|
949
|
ip_addr_set_loopback(addr);
|
| mbed714 |
0:d616ece2d859
|
950
|
return ERR_OK;
|
| mbed714 |
0:d616ece2d859
|
951
|
}
|
| mbed714 |
0:d616ece2d859
|
952
|
#endif /* LWIP_HAVE_LOOPIF */
|
| mbed714 |
0:d616ece2d859
|
953
|
|
| mbed714 |
0:d616ece2d859
|
954
|
/* host name already in octet notation? set ip addr and return ERR_OK */
|
| mbed714 |
0:d616ece2d859
|
955
|
ipaddr = ipaddr_addr(hostname);
|
| mbed714 |
0:d616ece2d859
|
956
|
if (ipaddr == IPADDR_NONE) {
|
| mbed714 |
0:d616ece2d859
|
957
|
/* already have this address cached? */
|
| mbed714 |
0:d616ece2d859
|
958
|
ipaddr = dns_lookup(hostname);
|
| mbed714 |
0:d616ece2d859
|
959
|
}
|
| mbed714 |
0:d616ece2d859
|
960
|
if (ipaddr != IPADDR_NONE) {
|
| mbed714 |
0:d616ece2d859
|
961
|
ip4_addr_set_u32(addr, ipaddr);
|
| mbed714 |
0:d616ece2d859
|
962
|
return ERR_OK;
|
| mbed714 |
0:d616ece2d859
|
963
|
}
|
| mbed714 |
0:d616ece2d859
|
964
|
|
| mbed714 |
0:d616ece2d859
|
965
|
/* queue query with specified callback */
|
| mbed714 |
0:d616ece2d859
|
966
|
return dns_enqueue(hostname, found, callback_arg);
|
| mbed714 |
0:d616ece2d859
|
967
|
}
|
| mbed714 |
0:d616ece2d859
|
968
|
|
| mbed714 |
0:d616ece2d859
|
969
|
#endif /* LWIP_DNS */
|
Daniel Peter