1 // SPDX-License-Identifier: GPL-2.0+
2 /* Copyright (C) 2024 Linaro Ltd. */
3
4 #include <command.h>
5 #include <console.h>
6 #include <env.h>
7 #include <lwip/dns.h>
8 #include <lwip/timeouts.h>
9 #include <net.h>
10 #include <time.h>
11
12 #define DNS_RESEND_MS 1000
13 #define DNS_TIMEOUT_MS 10000
14
15 struct dns_cb_arg {
16 ip_addr_t host_ipaddr;
17 const char *var;
18 bool done;
19 };
20
do_dns_tmr(void * arg)21 static void do_dns_tmr(void *arg)
22 {
23 dns_tmr();
24 }
25
dns_cb(const char * name,const ip_addr_t * ipaddr,void * arg)26 static void dns_cb(const char *name, const ip_addr_t *ipaddr, void *arg)
27 {
28 struct dns_cb_arg *dns_cb_arg = arg;
29 char *ipstr = ip4addr_ntoa(ipaddr);
30
31 dns_cb_arg->done = true;
32
33 if (!ipaddr) {
34 printf("DNS: host not found\n");
35 dns_cb_arg->host_ipaddr.addr = 0;
36 return;
37 }
38
39 dns_cb_arg->host_ipaddr.addr = ipaddr->addr;
40
41 if (dns_cb_arg->var)
42 env_set(dns_cb_arg->var, ipstr);
43 }
44
dns_loop(struct udevice * udev,const char * name,const char * var)45 static int dns_loop(struct udevice *udev, const char *name, const char *var)
46 {
47 struct dns_cb_arg dns_cb_arg = { };
48 struct netif *netif;
49 ip_addr_t ipaddr;
50 ulong start;
51 int ret;
52
53 dns_cb_arg.var = var;
54
55 netif = net_lwip_new_netif(udev);
56 if (!netif)
57 return CMD_RET_FAILURE;
58
59 if (net_lwip_dns_init()) {
60 net_lwip_remove_netif(netif);
61 return CMD_RET_FAILURE;
62 }
63
64 dns_cb_arg.done = false;
65
66 ret = dns_gethostbyname(name, &ipaddr, dns_cb, &dns_cb_arg);
67
68 if (ret == ERR_OK) {
69 dns_cb(name, &ipaddr, &dns_cb_arg);
70 } else if (ret == ERR_INPROGRESS) {
71 start = get_timer(0);
72 sys_timeout(DNS_RESEND_MS, do_dns_tmr, NULL);
73 do {
74 net_lwip_rx(udev, netif);
75 if (dns_cb_arg.done)
76 break;
77 if (ctrlc()) {
78 printf("\nAbort\n");
79 break;
80 }
81 } while (get_timer(start) < DNS_TIMEOUT_MS);
82 sys_untimeout(do_dns_tmr, NULL);
83 }
84
85 net_lwip_remove_netif(netif);
86
87 if (dns_cb_arg.done && dns_cb_arg.host_ipaddr.addr != 0) {
88 if (!var)
89 printf("%s\n", ipaddr_ntoa(&ipaddr));
90 return CMD_RET_SUCCESS;
91 }
92
93 return CMD_RET_FAILURE;
94 }
95
do_dns(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])96 int do_dns(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
97 {
98 char *name;
99 char *var = NULL;
100
101 if (argc == 1 || argc > 3)
102 return CMD_RET_USAGE;
103
104 name = argv[1];
105
106 if (argc == 3)
107 var = argv[2];
108
109 if (net_lwip_eth_start() < 0)
110 return CMD_RET_FAILURE;
111
112 return dns_loop(eth_get_dev(), name, var);
113 }
114