1 /* vi: set sw=4 ts=4: */
2 /*
3 * nameif.c - Naming Interfaces based on MAC address for busybox.
4 *
5 * Written 2000 by Andi Kleen.
6 * Busybox port 2002 by Nick Fedchik <nick@fedchik.org.ua>
7 * Glenn McGrath
8 * Extended matching support 2008 by Nico Erfurth <masta@perlgolf.de>
9 *
10 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
11 */
12 //config:config NAMEIF
13 //config: bool "nameif (6.6 kb)"
14 //config: default y
15 //config: select FEATURE_SYSLOG
16 //config: help
17 //config: nameif is used to rename network interface by its MAC address.
18 //config: Renamed interfaces MUST be in the down state.
19 //config: It is possible to use a file (default: /etc/mactab)
20 //config: with list of new interface names and MACs.
21 //config: Maximum interface name length: IFNAMSIZ = 16
22 //config: File fields are separated by space or tab.
23 //config: File format:
24 //config: # Comment
25 //config: new_interface_name XX:XX:XX:XX:XX:XX
26 //config:
27 //config:config FEATURE_NAMEIF_EXTENDED
28 //config: bool "Extended nameif"
29 //config: default y
30 //config: depends on NAMEIF
31 //config: help
32 //config: This extends the nameif syntax to support the bus_info, driver,
33 //config: phyaddr selectors. The syntax is compatible to the normal nameif.
34 //config: File format:
35 //config: new_interface_name driver=asix bus=usb-0000:00:08.2-3
36 //config: new_interface_name bus=usb-0000:00:08.2-3 00:80:C8:38:91:B5
37 //config: new_interface_name phy_address=2 00:80:C8:38:91:B5
38 //config: new_interface_name mac=00:80:C8:38:91:B5
39 //config: new_interface_name 00:80:C8:38:91:B5
40
41 //applet:IF_NAMEIF(APPLET_NOEXEC(nameif, nameif, BB_DIR_SBIN, BB_SUID_DROP, nameif))
42
43 //kbuild:lib-$(CONFIG_NAMEIF) += nameif.o
44
45 //usage:#define nameif_trivial_usage
46 //usage: IF_NOT_FEATURE_NAMEIF_EXTENDED(
47 //usage: "[-s] [-c FILE] [IFNAME HWADDR]..."
48 //usage: )
49 //usage: IF_FEATURE_NAMEIF_EXTENDED(
50 //usage: "[-s] [-c FILE] [IFNAME SELECTOR]..."
51 //usage: )
52 //usage:#define nameif_full_usage "\n\n"
53 //usage: "Rename network interface while it in the down state."
54 //usage: IF_NOT_FEATURE_NAMEIF_EXTENDED(
55 //usage: "\nThe device with address HWADDR is renamed to IFNAME."
56 //usage: )
57 //usage: IF_FEATURE_NAMEIF_EXTENDED(
58 //usage: "\nThe device matched by SELECTOR is renamed to IFNAME."
59 //usage: "\nSELECTOR can be a combination of:"
60 //usage: "\n driver=STRING"
61 //usage: "\n bus=STRING"
62 //usage: "\n phy_address=NUM"
63 //usage: "\n [mac=]XX:XX:XX:XX:XX:XX"
64 //usage: )
65 //usage: "\n"
66 //usage: "\n -c FILE Configuration file (default: /etc/mactab)"
67 //usage: "\n -s Log to syslog"
68 //usage:
69 //usage:#define nameif_example_usage
70 //usage: "$ nameif -s dmz0 00:A0:C9:8C:F6:3F\n"
71 //usage: " or\n"
72 //usage: "$ nameif -c /etc/my_mactab_file\n"
73
74 #include "libbb.h"
75 #include <syslog.h>
76 #include <net/if.h>
77 #include <netinet/ether.h>
78 #include <linux/sockios.h>
79
80 #ifndef IFNAMSIZ
81 #define IFNAMSIZ 16
82 #endif
83
84 /* Taken from linux/sockios.h */
85 #define SIOCSIFNAME 0x8923 /* set interface name */
86
87 /* Octets in one Ethernet addr, from <linux/if_ether.h> */
88 #define ETH_ALEN 6
89
90 #ifndef ifr_newname
91 #define ifr_newname ifr_ifru.ifru_slave
92 #endif
93
94 typedef struct ethtable_s {
95 struct ethtable_s *next;
96 struct ethtable_s *prev;
97 char *ifname;
98 struct ether_addr *mac;
99 #if ENABLE_FEATURE_NAMEIF_EXTENDED
100 char *bus_info;
101 char *driver;
102 int32_t phy_address;
103 #endif
104 } ethtable_t;
105
106 #if ENABLE_FEATURE_NAMEIF_EXTENDED
107 /* Cut'n'paste from ethtool.h */
108 #define ETHTOOL_BUSINFO_LEN 32
109 /* these strings are set to whatever the driver author decides... */
110 struct ethtool_drvinfo {
111 uint32_t cmd;
112 char driver[32]; /* driver short name, "tulip", "eepro100" */
113 char version[32]; /* driver version string */
114 char fw_version[32]; /* firmware version string, if applicable */
115 char bus_info[ETHTOOL_BUSINFO_LEN]; /* Bus info for this IF. */
116 /* For PCI devices, use pci_dev->slot_name. */
117 char reserved1[32];
118 char reserved2[16];
119 uint32_t n_stats; /* number of u64's from ETHTOOL_GSTATS */
120 uint32_t testinfo_len;
121 uint32_t eedump_len; /* Size of data from ETHTOOL_GEEPROM (bytes) */
122 uint32_t regdump_len; /* Size of data from ETHTOOL_GREGS (bytes) */
123 };
124
125 struct ethtool_cmd {
126 uint32_t cmd;
127 uint32_t supported; /* Features this interface supports */
128 uint32_t advertising; /* Features this interface advertises */
129 uint16_t speed; /* The forced speed, 10Mb, 100Mb, gigabit */
130 uint8_t duplex; /* Duplex, half or full */
131 uint8_t port; /* Which connector port */
132 uint8_t phy_address;
133 uint8_t transceiver; /* Which transceiver to use */
134 uint8_t autoneg; /* Enable or disable autonegotiation */
135 uint32_t maxtxpkt; /* Tx pkts before generating tx int */
136 uint32_t maxrxpkt; /* Rx pkts before generating rx int */
137 uint16_t speed_hi;
138 uint16_t reserved2;
139 uint32_t reserved[3];
140 };
141
142 #define ETHTOOL_GSET 0x00000001 /* Get settings. */
143 #define ETHTOOL_GDRVINFO 0x00000003 /* Get driver info. */
144 #endif
145
146
nameif_parse_selector(ethtable_t * ch,char * selector)147 static void nameif_parse_selector(ethtable_t *ch, char *selector)
148 {
149 struct ether_addr *lmac;
150 #if ENABLE_FEATURE_NAMEIF_EXTENDED
151 int found_selector = 0;
152
153 while (*selector) {
154 char *next;
155 #endif
156 selector = skip_whitespace(selector);
157 #if ENABLE_FEATURE_NAMEIF_EXTENDED
158 ch->phy_address = -1;
159 if (*selector == '\0')
160 break;
161 /* Search for the end .... */
162 next = skip_non_whitespace(selector);
163 if (*next)
164 *next++ = '\0';
165 /* Check for selectors, mac= is assumed */
166 if (is_prefixed_with(selector, "bus=")) {
167 ch->bus_info = xstrdup(selector + 4);
168 found_selector++;
169 } else if (is_prefixed_with(selector, "driver=")) {
170 ch->driver = xstrdup(selector + 7);
171 found_selector++;
172 } else if (is_prefixed_with(selector, "phyaddr=")) {
173 ch->phy_address = xatoi_positive(selector + 8);
174 found_selector++;
175 } else {
176 #endif
177 lmac = xmalloc(ETH_ALEN);
178 ch->mac = ether_aton_r(selector + (is_prefixed_with(selector, "mac=") ? 4 : 0), lmac);
179 if (ch->mac == NULL)
180 bb_error_msg_and_die("can't parse %s", selector);
181 #if ENABLE_FEATURE_NAMEIF_EXTENDED
182 found_selector++;
183 };
184 selector = next;
185 }
186 if (found_selector == 0)
187 bb_error_msg_and_die("no selectors found for %s", ch->ifname);
188 #endif
189 }
190
prepend_new_eth_table(ethtable_t ** clist,char * ifname,char * selector)191 static void prepend_new_eth_table(ethtable_t **clist, char *ifname, char *selector)
192 {
193 ethtable_t *ch;
194 if (strlen(ifname) >= IFNAMSIZ)
195 bb_error_msg_and_die("interface name '%s' too long", ifname);
196 ch = xzalloc(sizeof(*ch));
197 ch->ifname = xstrdup(ifname);
198 nameif_parse_selector(ch, selector);
199 ch->next = *clist;
200 if (*clist)
201 (*clist)->prev = ch;
202 *clist = ch;
203 }
204
205 #if ENABLE_FEATURE_CLEAN_UP
delete_eth_table(ethtable_t * ch)206 static void delete_eth_table(ethtable_t *ch)
207 {
208 free(ch->ifname);
209 #if ENABLE_FEATURE_NAMEIF_EXTENDED
210 free(ch->bus_info);
211 free(ch->driver);
212 #endif
213 free(ch->mac);
214 free(ch);
215 };
216 #else
217 void delete_eth_table(ethtable_t *ch);
218 #endif
219
220 int nameif_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
nameif_main(int argc UNUSED_PARAM,char ** argv)221 int nameif_main(int argc UNUSED_PARAM, char **argv)
222 {
223 ethtable_t *clist = NULL;
224 const char *fname = "/etc/mactab";
225 int ctl_sk;
226 ethtable_t *ch;
227 parser_t *parser;
228 char *token[2];
229
230 if (1 & getopt32(argv, "sc:", &fname)) {
231 openlog(applet_name, 0, LOG_LOCAL0);
232 /* Why not just "="? I assume logging to stderr
233 * can't hurt. 2>/dev/null if you don't like it: */
234 logmode |= LOGMODE_SYSLOG;
235 }
236 argv += optind;
237
238 if (argv[0]) {
239 do {
240 if (!argv[1])
241 bb_show_usage();
242 prepend_new_eth_table(&clist, argv[0], argv[1]);
243 argv += 2;
244 } while (*argv);
245 } else {
246 parser = config_open(fname);
247 while (config_read(parser, token, 2, 2, "# \t", PARSE_NORMAL))
248 prepend_new_eth_table(&clist, token[0], token[1]);
249 config_close(parser);
250 }
251
252 ctl_sk = xsocket(PF_INET, SOCK_DGRAM, 0);
253 parser = config_open2("/proc/net/dev", xfopen_for_read);
254
255 while (clist && config_read(parser, token, 2, 2, "\0: \t", PARSE_NORMAL)) {
256 struct ifreq ifr;
257 #if ENABLE_FEATURE_NAMEIF_EXTENDED
258 struct ethtool_drvinfo drvinfo;
259 struct ethtool_cmd eth_settings;
260 #endif
261 if (parser->lineno <= 2)
262 continue; /* Skip the first two lines */
263
264 /* Find the current interface name and copy it to ifr.ifr_name */
265 memset(&ifr, 0, sizeof(struct ifreq));
266 strncpy_IFNAMSIZ(ifr.ifr_name, token[0]);
267
268 #if ENABLE_FEATURE_NAMEIF_EXTENDED
269 /* Check for phy address */
270 memset(ð_settings, 0, sizeof(eth_settings));
271 eth_settings.cmd = ETHTOOL_GSET;
272 ifr.ifr_data = (caddr_t) ð_settings;
273 ioctl(ctl_sk, SIOCETHTOOL, &ifr);
274
275 /* Check for driver etc. */
276 memset(&drvinfo, 0, sizeof(drvinfo));
277 drvinfo.cmd = ETHTOOL_GDRVINFO;
278 ifr.ifr_data = (caddr_t) &drvinfo;
279 /* Get driver and businfo first, so we have it in drvinfo */
280 ioctl(ctl_sk, SIOCETHTOOL, &ifr);
281 #endif
282 ioctl(ctl_sk, SIOCGIFHWADDR, &ifr);
283
284 /* Search the list for a matching device */
285 for (ch = clist; ch; ch = ch->next) {
286 #if ENABLE_FEATURE_NAMEIF_EXTENDED
287 if (ch->bus_info && strcmp(ch->bus_info, drvinfo.bus_info) != 0)
288 continue;
289 if (ch->driver && strcmp(ch->driver, drvinfo.driver) != 0)
290 continue;
291 if (ch->phy_address != -1 && ch->phy_address != eth_settings.phy_address)
292 continue;
293 #endif
294 if (ch->mac && memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN) != 0)
295 continue;
296 /* if we came here, all selectors have matched */
297 goto found;
298 }
299 /* Nothing found for current interface */
300 continue;
301 found:
302 if (strcmp(ifr.ifr_name, ch->ifname) != 0) {
303 strcpy(ifr.ifr_newname, ch->ifname);
304 ioctl_or_perror_and_die(ctl_sk, SIOCSIFNAME, &ifr,
305 "can't change ifname %s to %s",
306 ifr.ifr_name, ch->ifname);
307 }
308 /* Remove list entry of renamed interface */
309 if (ch->prev != NULL)
310 ch->prev->next = ch->next;
311 else
312 clist = ch->next;
313 if (ch->next != NULL)
314 ch->next->prev = ch->prev;
315 if (ENABLE_FEATURE_CLEAN_UP)
316 delete_eth_table(ch);
317 } /* while */
318
319 if (ENABLE_FEATURE_CLEAN_UP) {
320 ethtable_t *next;
321 for (ch = clist; ch; ch = next) {
322 next = ch->next;
323 delete_eth_table(ch);
324 }
325 config_close(parser);
326 };
327
328 return 0;
329 }
330