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/*
* Copyright (c) 2017 Denys Vlasenko <vda.linux@googlemail.com>
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
//config:config IPCONFIG
//config: bool "ipconfig"
//config: default y
//config: help
//config: (Auto)configure network.
//applet:IF_IPCONFIG(APPLET(ipconfig, BB_DIR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_IPCONFIG) += ipconfig.o
#include <net/if.h>
#include "libbb.h"
struct globals {
int fixed;
const char *hostname;
};
#define G (*ptr_to_globals)
#define INIT_G() do { \
SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
} while (0)
struct dev {
const char *name;
uint8_t fixed;
uint32_t ip_addr;
uint32_t ip_netmask;
uint32_t ip_server;
uint32_t ip_router;
};
static int
parse_method(const char *method)
{
int fixed;
fixed = (method[0] != '\0');
if (fixed) {
/* if it's not "" */
fixed = index_in_strings(
/* 0 */ "on""\0"
/* 1 */ "any""\0"
/* 2 */ "both""\0"
/* 3 */ "dhcp""\0"
/* 4 */ "bootp""\0"
/* 5 */ "rarp""\0"
/* 6 */ "none""\0"
/* 7 */ "static""\0"
/* 8 */ "off""\0"
, method
);
if (fixed > 0)
fixed /= 6;
}
return fixed;
}
static uint32_t
parse_addr(const char *ip)
{
struct in_addr in;
if (inet_aton(ip, &in) == 0)
bb_error_msg_and_die("bad IP address '%s'", ip);
return in.s_addr;
}
static struct dev*
find_device(llist_t *iface_list, const char *name)
{
while (iface_list) {
struct dev *dev = (void*) iface_list->data;
if (strcmp(dev->name, name) == 0)
return dev;
iface_list = iface_list->link;
}
return NULL;
}
static void
set_from_template(struct dev *dev, struct dev *template)
{
if (template->ip_addr != 0)
dev->ip_addr = template->ip_addr;
if (template->ip_netmask != 0)
dev->ip_netmask = template->ip_netmask;
if (template->ip_server != 0)
dev->ip_server = template->ip_server;
if (template->ip_router != 0)
dev->ip_router = template->ip_router;
dev->fixed = template->fixed;
}
// "ip=PROTO" - also implies -o
// "nfsaddrs=PROTO" - also implies -o
// "<devname>"
// "[ip=/nfsaddrs=]IP:SERVER_IP:ROUTER:NETMASK:HOSTNAME:IFACE:METHOD"
// all optional. trailing empty :: can be skipped, only one : needs to be there
// (to distinguish from other formats).
// ":::::eth0" - dhcp on eth0
// ":" - dhcp on all ifaces
// "::1.2.3.4" - dhcp on all ifaces, gateway is 1.2.3.4 (fairly nonsensical)
static void
add_all_devices(llist_t **iface_list, struct dev *template);
static struct dev*
add_device(llist_t **iface_list, char *ip)
{
struct dev *dev;
dev = xzalloc(sizeof(*dev));
dev->fixed = G.fixed;
if (strncmp("ip=", ip, 3) == 0
|| strncmp("nfsaddrs=", ip, 9) == 0
) {
int fixed;
ip = strchr(ip, '=') + 1;
fixed = parse_method(ip);
if (fixed >= 0) {
add_all_devices(iface_list, dev);
free(dev);
return NULL;
}
}
if (!strchr(ip, ':')) {
dev->name = ip;
} else {
unsigned opt = 0;
while (ip && *ip) {
char *next = strchr(ip, ':');
if (next)
*next++ = '\0';
if (opt > 6)
bb_error_msg_and_die("too many options for %s", dev->name);
if (ip[0]) switch (opt) {
case 0:
dev->ip_addr = parse_addr(ip);
break;
case 1:
dev->ip_server = parse_addr(ip);
break;
case 2:
dev->ip_router = parse_addr(ip);
break;
case 3:
dev->ip_netmask = parse_addr(ip);
break;
case 4:
if (G.hostname && strcmp(G.hostname, ip) != 0)
bb_error_msg_and_die("hostname must be the same");
G.hostname = ip;
break;
case 5:
dev->name = ip;
break;
case 6:
dev->fixed = parse_method(ip);
break;
}
ip = next;
opt++;
}
}
if (dev->name == NULL
|| strcmp(dev->name, "all") == 0
) {
add_all_devices(iface_list, dev);
free(dev);
return NULL;
}
llist_add_to_end(iface_list, dev);
return dev;
}
static void
add_all_devices(llist_t **iface_list, struct dev *template)
{
DIR *d;
struct dirent *de;
#define sys_class_net "/sys/class/net"
/* All forms of "config all ifaces" imply -o */
option_mask32 |= 1;
d = opendir(sys_class_net);
if (!d)
return;
while ((de = readdir(d)) != NULL) {
struct dev *dev;
char *filename;
char p[sizeof(long)*3];
unsigned long flags;
int r;
/* Exclude devices beginning with dots as well as . and .. */
if (de->d_name[0] == '.')
continue;
filename = xasprintf("%s/%s/flags", sys_class_net, de->d_name);
r = open_read_close(filename, p, sizeof(p) - 1);
free(filename);
if (r < 0)
continue;
p[r] = '\0';
/* file's format is "0xNNNN\n" */
flags = bb_strtoul(p, NULL, 0);
/*
* Heuristic for if this is a reasonable boot interface.
* This is the same logic the in-kernel ipconfig uses.
*/
if (flags & IFF_LOOPBACK)
continue;
if (!(flags & (IFF_BROADCAST | IFF_POINTOPOINT)))
continue;
if (find_device(*iface_list, de->d_name))
continue;
dev = add_device(iface_list, xstrdup(de->d_name));
if (dev)
set_from_template(dev, template);
}
closedir(d);
#undef sys_class_net
}
//usage:#define ipconfig_trivial_usage
//usage: "[-c METHOD] [-t TIMEOUT] [-on] [-i VENDOR_ID] [-p PORT] [-d] IFACE..."
//usage:#define ipconfig_full_usage "\n\n"
//usage: "(Auto)configure network"
//usage: "\n"
//usage: "\n"" -c METHOD off/none/static or on/dhcp (default)"
//usage: "\n"" -t SECONDS Give up after SECONDS"
//usage: "\n"" -o Stop after one interface is configured"
//usage: "\n"" -n Dry run"
//usage: "\n"" -i VENDOR_ID DHCP vendor id (default '')"
//usage: "\n"" -p PORT DHCP port to use"
//usage: "\n"" [-d] IFACE... Interface(s)"
//usage: "\n"
//usage: "\n"" IFACE can be:"
//usage: "\n"" all - configure all interfaces"
//usage: "\n"" IFACE - configure this interface"
//usage: "\n"" IP:SERVER_IP:ROUTER:NETMASK:HOSTNAME:IFACE:METHOD (all optional)"
// TIMEOUT defaults to infinite
// -d actually is an option with an argument
// (not a clue why klibc-utils has two ways to specify interfaces)
int ipconfig_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int ipconfig_main(int argc UNUSED_PARAM, char **argv)
{
const char *method = "";
const char *vendor_id = "";
llist_t *devname_list = NULL;
llist_t *iface_list;
int timeout = -1;
unsigned port;
unsigned opt;
INIT_G();
opt = getopt32(argv,
"onc:t:i:p:+d:*",
&method, &timeout, &vendor_id, &port, &devname_list
);
argv += optind;
G.fixed = parse_method(method);
if (G.fixed < 0)
bb_show_usage();
iface_list = NULL;
while (devname_list)
add_device(&iface_list, (char*) llist_pop(&devname_list));
while (*argv)
add_device(&iface_list, *argv++);
while (iface_list) {
struct dev *dev = (void*) iface_list->data;
printf("name:'%s'\n", dev->name);
printf("fixed:%u\n" , dev->fixed);
printf("ip:%s/" , inet_ntoa(*(struct in_addr*)&dev->ip_addr));
printf("%s\n" , inet_ntoa(*(struct in_addr*)&dev->ip_netmask));
printf("server:%s\n", inet_ntoa(*(struct in_addr*)&dev->ip_server));
printf("router:%s\n", inet_ntoa(*(struct in_addr*)&dev->ip_router));
iface_list = iface_list->link;
}
bb_error_msg("hostname:'%s'", G.hostname);
bb_error_msg("fixed:%u", G.fixed);
return EXIT_SUCCESS;
}
//After device is configured, write out a "/run/net-IFACE.conf" file:
// // udchcp env values:
//write_option("DEVICE", dev->name); interface=eth0
//write_option("PROTO", method);
//write_option("IPV4ADDR", dev->ip_addr); ip=10.43.17.38
//write_option("IPV4BROADCAST", dev->ip_broadcast); subnet=255.255.255.0 mask=24
//write_option("IPV4NETMASK", dev->ip_netmask); subnet=255.255.255.0 mask=24
//write_option("IPV4GATEWAY", dev->ip_gateway); router=10.43.17.254
//write_option("IPV4DNS0", dev->ip_nameserver[0]); dns=10.38.5.26 10.11.5.19
//write_option("IPV4DNS1", dev->ip_nameserver[1]); dns=10.38.5.26 10.11.5.19
//write_option("HOSTNAME", dev->hostname); hostname="STR"
//write_option("DNSDOMAIN", dev->dnsdomainname); domain=domain.com
//write_option("NISDOMAIN", dev->nisdomainname); nisdomain="STR"
//write_option("ROOTSERVER", my_inet_ntoa(dev->ip_server)); serverid=10.44.6.2
//write_option("ROOTPATH", dev->bootpath); rootpath="STR"
//write_option("filename", dev->filename); boot_file=/pxelinux.0
//write_option("UPTIME", dev->uptime); sysinfo()->uptime
//write_option("DHCPLEASETIME", dev->dhcpleasetime); lease=44148
//write_option("DOMAINSEARCH", dev->domainsearch); search="ABC DEF"
//
//(write_option writes out single-quote escaped string, VAR='VAL')