text: /* vi: set sw=4 ts=4: */
  /*
   * nameif.c - Naming Interfaces based on MAC address for busybox.
   *
   * Written 2000 by Andi Kleen.
   * Busybox port 2002 by Nick Fedchik <nick@fedchik.org.ua>
   *			Glenn McGrath
   * Extended matching support 2008 by Nico Erfurth <masta@perlgolf.de>
   *
   * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   */
  //config:config NAMEIF
  //config:	bool "nameif (6.6 kb)"
  //config:	default y
  //config:	select FEATURE_SYSLOG
  //config:	help
  //config:	nameif is used to rename network interface by its MAC address.
  //config:	Renamed interfaces MUST be in the down state.
  //config:	It is possible to use a file (default: /etc/mactab)
  //config:	with list of new interface names and MACs.
  //config:	Maximum interface name length: IFNAMSIZ = 16
  //config:	File fields are separated by space or tab.
  //config:	File format:
  //config:		# Comment
  //config:		new_interface_name  XX:XX:XX:XX:XX:XX
  //config:
  //config:config FEATURE_NAMEIF_EXTENDED
  //config:	bool "Extended nameif"
  //config:	default y
  //config:	depends on NAMEIF
  //config:	help
  //config:	This extends the nameif syntax to support the bus_info, driver,
  //config:	phyaddr selectors. The syntax is compatible to the normal nameif.
  //config:	File format:
  //config:		new_interface_name  driver=asix bus=usb-0000:00:08.2-3
  //config:		new_interface_name  bus=usb-0000:00:08.2-3 00:80:C8:38:91:B5
  //config:		new_interface_name  phy_address=2 00:80:C8:38:91:B5
  //config:		new_interface_name  mac=00:80:C8:38:91:B5
  //config:		new_interface_name  00:80:C8:38:91:B5
  
  //applet:IF_NAMEIF(APPLET_NOEXEC(nameif, nameif, BB_DIR_SBIN, BB_SUID_DROP, nameif))
  
  //kbuild:lib-$(CONFIG_NAMEIF) += nameif.o
  
  //usage:#define nameif_trivial_usage
  //usage:	IF_NOT_FEATURE_NAMEIF_EXTENDED(
  //usage:		"[-s] [-c FILE] [IFNAME HWADDR]..."
  //usage:	)
  //usage:	IF_FEATURE_NAMEIF_EXTENDED(
  //usage:		"[-s] [-c FILE] [IFNAME SELECTOR]..."
  //usage:	)
  //usage:#define nameif_full_usage "\n\n"
  //usage:	"Rename network interface while it in the down state."
  //usage:	IF_NOT_FEATURE_NAMEIF_EXTENDED(
  //usage:     "\nThe device with address HWADDR is renamed to IFNAME."
  //usage:	)
  //usage:	IF_FEATURE_NAMEIF_EXTENDED(
  //usage:     "\nThe device matched by SELECTOR is renamed to IFNAME."
  //usage:     "\nSELECTOR can be a combination of:"
  //usage:     "\n	driver=STRING"
  //usage:     "\n	bus=STRING"
  //usage:     "\n	phy_address=NUM"
  //usage:     "\n	[mac=]XX:XX:XX:XX:XX:XX"
  //usage:	)
  //usage:     "\n"
  //usage:     "\n	-c FILE	Configuration file (default: /etc/mactab)"
  //usage:     "\n	-s	Log to syslog"
  //usage:
  //usage:#define nameif_example_usage
  //usage:       "$ nameif -s dmz0 00:A0:C9:8C:F6:3F\n"
  //usage:       " or\n"
  //usage:       "$ nameif -c /etc/my_mactab_file\n"
  
  #include "libbb.h"
  #include <syslog.h>
  #include <net/if.h>
  #include <netinet/ether.h>
  #include <linux/sockios.h>
  
  #ifndef IFNAMSIZ
  #define IFNAMSIZ 16
  #endif
  
  /* Taken from linux/sockios.h */
  #define SIOCSIFNAME  0x8923  /* set interface name */
  
  /* Octets in one Ethernet addr, from <linux/if_ether.h> */
  #define ETH_ALEN     6
  
  #ifndef ifr_newname
  #define ifr_newname ifr_ifru.ifru_slave
  #endif
  
  typedef struct ethtable_s {
  	struct ethtable_s *next;
  	struct ethtable_s *prev;
  	char *ifname;
  	struct ether_addr *mac;
  #if ENABLE_FEATURE_NAMEIF_EXTENDED
  	char *bus_info;
  	char *driver;
  	int32_t phy_address;
  #endif
  } ethtable_t;
  
  #if ENABLE_FEATURE_NAMEIF_EXTENDED
  /* Cut'n'paste from ethtool.h */
  #define ETHTOOL_BUSINFO_LEN 32
  /* these strings are set to whatever the driver author decides... */
  struct ethtool_drvinfo {
  	uint32_t cmd;
  	char  driver[32]; /* driver short name, "tulip", "eepro100" */
  	char  version[32];  /* driver version string */
  	char  fw_version[32]; /* firmware version string, if applicable */
  	char  bus_info[ETHTOOL_BUSINFO_LEN];  /* Bus info for this IF. */
  	/* For PCI devices, use pci_dev->slot_name. */
  	char  reserved1[32];
  	char  reserved2[16];
  	uint32_t n_stats;  /* number of u64's from ETHTOOL_GSTATS */
  	uint32_t testinfo_len;
  	uint32_t eedump_len; /* Size of data from ETHTOOL_GEEPROM (bytes) */
  	uint32_t regdump_len;  /* Size of data from ETHTOOL_GREGS (bytes) */
  };
  
  struct ethtool_cmd {
  	uint32_t   cmd;
  	uint32_t   supported;      /* Features this interface supports */
  	uint32_t   advertising;    /* Features this interface advertises */
  	uint16_t   speed;          /* The forced speed, 10Mb, 100Mb, gigabit */
  	uint8_t    duplex;         /* Duplex, half or full */
  	uint8_t    port;           /* Which connector port */
  	uint8_t    phy_address;
  	uint8_t    transceiver;    /* Which transceiver to use */
  	uint8_t    autoneg;        /* Enable or disable autonegotiation */
  	uint32_t   maxtxpkt;       /* Tx pkts before generating tx int */
  	uint32_t   maxrxpkt;       /* Rx pkts before generating rx int */
  	uint16_t   speed_hi;
  	uint16_t   reserved2;
  	uint32_t   reserved[3];
  };
  
  #define ETHTOOL_GSET      0x00000001 /* Get settings. */
  #define ETHTOOL_GDRVINFO  0x00000003 /* Get driver info. */
  #endif
  
  
  static void nameif_parse_selector(ethtable_t *ch, char *selector)
  {
  	struct ether_addr *lmac;
  #if ENABLE_FEATURE_NAMEIF_EXTENDED
  	int found_selector = 0;
  
  	while (*selector) {
  		char *next;
  #endif
  		selector = skip_whitespace(selector);
  #if ENABLE_FEATURE_NAMEIF_EXTENDED
  		ch->phy_address = -1;
  		if (*selector == '\0')
  			break;
  		/* Search for the end .... */
  		next = skip_non_whitespace(selector);
  		if (*next)
  			*next++ = '\0';
  		/* Check for selectors, mac= is assumed */
  		if (is_prefixed_with(selector, "bus=")) {
  			ch->bus_info = xstrdup(selector + 4);
  			found_selector++;
  		} else if (is_prefixed_with(selector, "driver=")) {
  			ch->driver = xstrdup(selector + 7);
  			found_selector++;
  		} else if (is_prefixed_with(selector, "phyaddr=")) {
  			ch->phy_address = xatoi_positive(selector + 8);
  			found_selector++;
  		} else {
  #endif
  			lmac = xmalloc(ETH_ALEN);
  			ch->mac = ether_aton_r(selector + (is_prefixed_with(selector, "mac=") ? 4 : 0), lmac);
  			if (ch->mac == NULL)
  				bb_error_msg_and_die("can't parse %s", selector);
  #if  ENABLE_FEATURE_NAMEIF_EXTENDED
  			found_selector++;
  		};
  		selector = next;
  	}
  	if (found_selector == 0)
  		bb_error_msg_and_die("no selectors found for %s", ch->ifname);
  #endif
  }
  
  static void prepend_new_eth_table(ethtable_t **clist, char *ifname, char *selector)
  {
  	ethtable_t *ch;
  	if (strlen(ifname) >= IFNAMSIZ)
  		bb_error_msg_and_die("interface name '%s' too long", ifname);
  	ch = xzalloc(sizeof(*ch));
  	ch->ifname = xstrdup(ifname);
  	nameif_parse_selector(ch, selector);
  	ch->next = *clist;
  	if (*clist)
  		(*clist)->prev = ch;
  	*clist = ch;
  }
  
  #if ENABLE_FEATURE_CLEAN_UP
  static void delete_eth_table(ethtable_t *ch)
  {
  	free(ch->ifname);
  #if ENABLE_FEATURE_NAMEIF_EXTENDED
  	free(ch->bus_info);
  	free(ch->driver);
  #endif
  	free(ch->mac);
  	free(ch);
  };
  #else
  void delete_eth_table(ethtable_t *ch);
  #endif
  
  int nameif_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  int nameif_main(int argc UNUSED_PARAM, char **argv)
  {
  	ethtable_t *clist = NULL;
  	const char *fname = "/etc/mactab";
  	int ctl_sk;
  	ethtable_t *ch;
  	parser_t *parser;
  	char *token[2];
  
  	if (1 & getopt32(argv, "sc:", &fname)) {
  		openlog(applet_name, 0, LOG_LOCAL0);
  		/* Why not just "="? I assume logging to stderr
  		 * can't hurt. 2>/dev/null if you don't like it: */
  		logmode |= LOGMODE_SYSLOG;
  	}
  	argv += optind;
  
  	if (argv[0]) {
  		do {
  			if (!argv[1])
  				bb_show_usage();
  			prepend_new_eth_table(&clist, argv[0], argv[1]);
  			argv += 2;
  		} while (*argv);
  	} else {
  		parser = config_open(fname);
  		while (config_read(parser, token, 2, 2, "# \t", PARSE_NORMAL))
  			prepend_new_eth_table(&clist, token[0], token[1]);
  		config_close(parser);
  	}
  
  	ctl_sk = xsocket(PF_INET, SOCK_DGRAM, 0);
  	parser = config_open2("/proc/net/dev", xfopen_for_read);
  
  	while (clist && config_read(parser, token, 2, 2, "\0: \t", PARSE_NORMAL)) {
  		struct ifreq ifr;
  #if  ENABLE_FEATURE_NAMEIF_EXTENDED
  		struct ethtool_drvinfo drvinfo;
  		struct ethtool_cmd eth_settings;
  #endif
  		if (parser->lineno <= 2)
  			continue; /* Skip the first two lines */
  
  		/* Find the current interface name and copy it to ifr.ifr_name */
  		memset(&ifr, 0, sizeof(struct ifreq));
  		strncpy_IFNAMSIZ(ifr.ifr_name, token[0]);
  
  #if ENABLE_FEATURE_NAMEIF_EXTENDED
  		/* Check for phy address */
  		memset(&eth_settings, 0, sizeof(eth_settings));
  		eth_settings.cmd = ETHTOOL_GSET;
  		ifr.ifr_data = (caddr_t) &eth_settings;
  		ioctl(ctl_sk, SIOCETHTOOL, &ifr);
  
  		/* Check for driver etc. */
  		memset(&drvinfo, 0, sizeof(drvinfo));
  		drvinfo.cmd = ETHTOOL_GDRVINFO;
  		ifr.ifr_data = (caddr_t) &drvinfo;
  		/* Get driver and businfo first, so we have it in drvinfo */
  		ioctl(ctl_sk, SIOCETHTOOL, &ifr);
  #endif
  		ioctl(ctl_sk, SIOCGIFHWADDR, &ifr);
  
  		/* Search the list for a matching device */
  		for (ch = clist; ch; ch = ch->next) {
  #if ENABLE_FEATURE_NAMEIF_EXTENDED
  			if (ch->bus_info && strcmp(ch->bus_info, drvinfo.bus_info) != 0)
  				continue;
  			if (ch->driver && strcmp(ch->driver, drvinfo.driver) != 0)
  				continue;
  			if (ch->phy_address != -1 && ch->phy_address != eth_settings.phy_address)
  				continue;
  #endif
  			if (ch->mac && memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN) != 0)
  				continue;
  			/* if we came here, all selectors have matched */
  			goto found;
  		}
  		/* Nothing found for current interface */
  		continue;
   found:
  		if (strcmp(ifr.ifr_name, ch->ifname) != 0) {
  			strcpy(ifr.ifr_newname, ch->ifname);
  			ioctl_or_perror_and_die(ctl_sk, SIOCSIFNAME, &ifr,
  					"can't change ifname %s to %s",
  					ifr.ifr_name, ch->ifname);
  		}
  		/* Remove list entry of renamed interface */
  		if (ch->prev != NULL)
  			ch->prev->next = ch->next;
  		else
  			clist = ch->next;
  		if (ch->next != NULL)
  			ch->next->prev = ch->prev;
  		if (ENABLE_FEATURE_CLEAN_UP)
  			delete_eth_table(ch);
  	} /* while */
  
  	if (ENABLE_FEATURE_CLEAN_UP) {
  		ethtable_t *next;
  		for (ch = clist; ch; ch = next) {
  			next = ch->next;
  			delete_eth_table(ch);
  		}
  		config_close(parser);
  	};
  
  	return 0;
  }
  