mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-05 19:10:13 +00:00
9fb625ce05
Move env_set() over to the new header file. Acked-by: Joe Hershberger <joe.hershberger@ni.com> Signed-off-by: Simon Glass <sjg@chromium.org>
208 lines
4.8 KiB
C
208 lines
4.8 KiB
C
/*
|
|
* DNS support driver
|
|
*
|
|
* Copyright (c) 2008 Pieter Voorthuijsen <pieter.voorthuijsen@prodrive.nl>
|
|
* Copyright (c) 2009 Robin Getz <rgetz@blackfin.uclinux.org>
|
|
*
|
|
* This is a simple DNS implementation for U-Boot. It will use the first IP
|
|
* in the DNS response as net_server_ip. This can then be used for any other
|
|
* network related activities.
|
|
*
|
|
* The packet handling is partly based on TADNS, original copyrights
|
|
* follow below.
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* Copyright (c) 2004-2005 Sergey Lyubka <valenok@gmail.com>
|
|
*
|
|
* "THE BEER-WARE LICENSE" (Revision 42):
|
|
* Sergey Lyubka wrote this file. As long as you retain this notice you
|
|
* can do whatever you want with this stuff. If we meet some day, and you think
|
|
* this stuff is worth it, you can buy me a beer in return.
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <command.h>
|
|
#include <env.h>
|
|
#include <net.h>
|
|
#include <asm/unaligned.h>
|
|
|
|
#include "dns.h"
|
|
|
|
char *net_dns_resolve; /* The host to resolve */
|
|
char *net_dns_env_var; /* The envvar to store the answer in */
|
|
|
|
static int dns_our_port;
|
|
|
|
static void dns_send(void)
|
|
{
|
|
struct header *header;
|
|
int n, name_len;
|
|
uchar *p, *pkt;
|
|
const char *s;
|
|
const char *name;
|
|
enum dns_query_type qtype = DNS_A_RECORD;
|
|
|
|
name = net_dns_resolve;
|
|
pkt = (uchar *)(net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE);
|
|
p = pkt;
|
|
|
|
/* Prepare DNS packet header */
|
|
header = (struct header *)pkt;
|
|
header->tid = 1;
|
|
header->flags = htons(0x100); /* standard query */
|
|
header->nqueries = htons(1); /* Just one query */
|
|
header->nanswers = 0;
|
|
header->nauth = 0;
|
|
header->nother = 0;
|
|
|
|
/* Encode DNS name */
|
|
name_len = strlen(name);
|
|
p = (uchar *)&header->data; /* For encoding host name into packet */
|
|
|
|
do {
|
|
s = strchr(name, '.');
|
|
if (!s)
|
|
s = name + name_len;
|
|
|
|
n = s - name; /* Chunk length */
|
|
*p++ = n; /* Copy length */
|
|
memcpy(p, name, n); /* Copy chunk */
|
|
p += n;
|
|
|
|
if (*s == '.')
|
|
n++;
|
|
|
|
name += n;
|
|
name_len -= n;
|
|
} while (*s != '\0');
|
|
|
|
*p++ = 0; /* Mark end of host name */
|
|
*p++ = 0; /* Some servers require double null */
|
|
*p++ = (unsigned char) qtype; /* Query Type */
|
|
|
|
*p++ = 0;
|
|
*p++ = 1; /* Class: inet, 0x0001 */
|
|
|
|
n = p - pkt; /* Total packet length */
|
|
debug("Packet size %d\n", n);
|
|
|
|
dns_our_port = random_port();
|
|
|
|
net_send_udp_packet(net_server_ethaddr, net_dns_server,
|
|
DNS_SERVICE_PORT, dns_our_port, n);
|
|
debug("DNS packet sent\n");
|
|
}
|
|
|
|
static void dns_timeout_handler(void)
|
|
{
|
|
puts("Timeout\n");
|
|
net_set_state(NETLOOP_FAIL);
|
|
}
|
|
|
|
static void dns_handler(uchar *pkt, unsigned dest, struct in_addr sip,
|
|
unsigned src, unsigned len)
|
|
{
|
|
struct header *header;
|
|
const unsigned char *p, *e, *s;
|
|
u16 type, i;
|
|
int found, stop, dlen;
|
|
char ip_str[22];
|
|
struct in_addr ip_addr;
|
|
|
|
|
|
debug("%s\n", __func__);
|
|
if (dest != dns_our_port)
|
|
return;
|
|
|
|
for (i = 0; i < len; i += 4)
|
|
debug("0x%p - 0x%.2x 0x%.2x 0x%.2x 0x%.2x\n",
|
|
pkt+i, pkt[i], pkt[i+1], pkt[i+2], pkt[i+3]);
|
|
|
|
/* We sent one query. We want to have a single answer: */
|
|
header = (struct header *)pkt;
|
|
if (ntohs(header->nqueries) != 1)
|
|
return;
|
|
|
|
/* Received 0 answers */
|
|
if (header->nanswers == 0) {
|
|
puts("DNS: host not found\n");
|
|
net_set_state(NETLOOP_SUCCESS);
|
|
return;
|
|
}
|
|
|
|
/* Skip host name */
|
|
s = &header->data[0];
|
|
e = pkt + len;
|
|
for (p = s; p < e && *p != '\0'; p++)
|
|
continue;
|
|
|
|
/* We sent query class 1, query type 1 */
|
|
if (&p[5] > e || get_unaligned_be16(p+1) != DNS_A_RECORD) {
|
|
puts("DNS: response was not an A record\n");
|
|
net_set_state(NETLOOP_SUCCESS);
|
|
return;
|
|
}
|
|
|
|
/* Go to the first answer section */
|
|
p += 5;
|
|
|
|
/* Loop through the answers, we want A type answer */
|
|
for (found = stop = 0; !stop && &p[12] < e; ) {
|
|
/* Skip possible name in CNAME answer */
|
|
if (*p != 0xc0) {
|
|
while (*p && &p[12] < e)
|
|
p++;
|
|
p--;
|
|
}
|
|
debug("Name (Offset in header): %d\n", p[1]);
|
|
|
|
type = get_unaligned_be16(p+2);
|
|
debug("type = %d\n", type);
|
|
if (type == DNS_CNAME_RECORD) {
|
|
/* CNAME answer. shift to the next section */
|
|
debug("Found canonical name\n");
|
|
dlen = get_unaligned_be16(p+10);
|
|
debug("dlen = %d\n", dlen);
|
|
p += 12 + dlen;
|
|
} else if (type == DNS_A_RECORD) {
|
|
debug("Found A-record\n");
|
|
found = 1;
|
|
stop = 1;
|
|
} else {
|
|
debug("Unknown type\n");
|
|
stop = 1;
|
|
}
|
|
}
|
|
|
|
if (found && &p[12] < e) {
|
|
dlen = get_unaligned_be16(p+10);
|
|
p += 12;
|
|
memcpy(&ip_addr, p, 4);
|
|
|
|
if (p + dlen <= e) {
|
|
ip_to_string(ip_addr, ip_str);
|
|
printf("%s\n", ip_str);
|
|
if (net_dns_env_var)
|
|
env_set(net_dns_env_var, ip_str);
|
|
} else {
|
|
puts("server responded with invalid IP number\n");
|
|
}
|
|
}
|
|
|
|
net_set_state(NETLOOP_SUCCESS);
|
|
}
|
|
|
|
void dns_start(void)
|
|
{
|
|
debug("%s\n", __func__);
|
|
|
|
net_set_timeout_handler(DNS_TIMEOUT, dns_timeout_handler);
|
|
net_set_udp_handler(dns_handler);
|
|
|
|
/* Clear a previous MAC address, the server IP might have changed. */
|
|
memset(net_server_ethaddr, 0, sizeof(net_server_ethaddr));
|
|
|
|
dns_send();
|
|
}
|