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author | 2000-10-18 17:26:29 +0000 | |
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committer | 2000-10-18 17:26:29 +0000 | |
commit | cf76b8584ce2c51f01f94940406bf0dfad0a4d14 (patch) | |
tree | 561ac740233abbab50c2eb33c4a92f9147dffa47 /nameif.c | |
parent | patch from Alex Belits <abelits@phobos.illtel.denver.co.us> to support (diff) | |
download | net-tools-cf76b8584ce2c51f01f94940406bf0dfad0a4d14.tar.gz net-tools-cf76b8584ce2c51f01f94940406bf0dfad0a4d14.tar.bz2 net-tools-cf76b8584ce2c51f01f94940406bf0dfad0a4d14.zip |
Add nameif, a small tool for logical network interface naming.
Diffstat (limited to 'nameif.c')
-rw-r--r-- | nameif.c | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/nameif.c b/nameif.c new file mode 100644 index 0000000..8d79b50 --- /dev/null +++ b/nameif.c @@ -0,0 +1,302 @@ +/* + * Name Interfaces based on MAC address. + * Writen 2000 by Andi Kleen. + * Subject to the Gnu Public License, version 2. + * TODO: make it support token ring etc. + * $Id: nameif.c,v 1.1 2000/10/18 17:26:29 ak Exp $ + */ +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif +#include <stdio.h> +#include <getopt.h> +#include <sys/syslog.h> +#include <errno.h> +#include <stdlib.h> +#include <ctype.h> +#include <string.h> +#include <stdarg.h> +#include <sys/socket.h> +#include <sys/ioctl.h> +#include <net/if.h> +#include <linux/sockios.h> +#include <errno.h> +#include "intl.h" + +const char default_conf[] = "/etc/mactab"; +const char *fname = default_conf; +int use_syslog; +int ctl_sk = -1; + +void err(char *msg) +{ + if (use_syslog) { + syslog(LOG_ERR,"%s: %m", msg); + } else { + perror(msg); + } + exit(1); +} + +void complain(char *fmt, ...) +{ + va_list ap; + va_start(ap,fmt); + if (use_syslog) { + vsyslog(LOG_ERR,fmt,ap); + } else { + vfprintf(stderr,fmt,ap); + fputc('\n',stderr); + } + va_end(ap); + exit(1); +} + +void warning(char *fmt, ...) +{ + va_list ap; + va_start(ap,fmt); + if (use_syslog) { + vsyslog(LOG_ERR,fmt,ap); + } else { + vfprintf(stderr,fmt,ap); + fputc('\n',stderr); + } + va_end(ap); +} + +int parsemac(char *str, unsigned char *mac) +{ + char *s; + while ((s = strsep(&str, ":")) != NULL) { + unsigned byte; + if (sscanf(s,"%x", &byte)!=1 || byte > 0xff) + return -1; + *mac++ = byte; + } + return 0; +} + +void *xmalloc(unsigned sz) +{ + void *p = calloc(sz,1); + if (!p) errno=ENOMEM, err("xmalloc"); + return p; +} + +void opensock(void) +{ + if (ctl_sk < 0) + ctl_sk = socket(PF_INET,SOCK_DGRAM,0); +} + +#ifndef ifr_newname +#define ifr_newname ifr_ifru.ifru_slave +#endif + +int setname(char *oldname, char *newname) +{ + struct ifreq ifr; + opensock(); + memset(&ifr,0,sizeof(struct ifreq)); + strcpy(ifr.ifr_name, oldname); + strcpy(ifr.ifr_newname, newname); + return ioctl(ctl_sk, SIOCSIFNAME, &ifr); +} + +int getmac(char *name, unsigned char *mac) +{ + int r; + struct ifreq ifr; + opensock(); + memset(&ifr,0,sizeof(struct ifreq)); + strcpy(ifr.ifr_name, name); + r = ioctl(ctl_sk, SIOCGIFHWADDR, &ifr); + memcpy(mac, ifr.ifr_hwaddr.sa_data, 6); + return r; +} + +struct change { + struct change *next,**pprev; + char ifname[IFNAMSIZ+1]; + unsigned char mac[6]; +}; +struct change *clist; + +struct change *lookupmac(unsigned char *mac) +{ + struct change *ch; + for (ch = clist;ch;ch = ch->next) + if (!memcmp(ch->mac, mac, 6)) + return ch; + return NULL; +} + +int addchange(char *p, struct change *ch, char *pos) +{ + if (strchr(ch->ifname, ':')) + warning(_("alias device %s at %s probably has no mac"), + ch->ifname, pos); + if (parsemac(p,ch->mac) < 0) + complain(_("cannot parse MAC `%s' at %s"), p, pos); + if (clist) + clist->pprev = &ch->next; + ch->next = clist; + ch->pprev = &clist; + clist = ch; + return 0; +} + +void readconf(void) +{ + char *line; + size_t linel; + int linenum; + FILE *ifh; + char *p; + int n; + + ifh = fopen(fname, "r"); + if (!ifh) + complain(_("opening configuration file %s: %s"),fname,strerror(errno)); + + line = NULL; + linel = 0; + linenum = 1; + while (getdelim(&line, &linel, '\n', ifh) > 0) { + struct change *ch = xmalloc(sizeof(struct change)); + char pos[20]; + + sprintf(pos, _("line %d"), linenum); + + if ((p = strchr(line,'#')) != NULL) + *p = '\0'; + p = line; + while (isspace(*p)) + ++p; + if (*p == '\0') + continue; + n = strcspn(p, " \t"); + if (n > IFNAMSIZ) + complain(_("interface name too long at line %d"), line); + memcpy(ch->ifname, p, n); + ch->ifname[n] = 0; + p += n; + p += strspn(p, " \t"); + n = strspn(p, "0123456789ABCDEFabcdef:"); + p[n] = 0; + addchange(p, ch, pos); + linenum++; + } + fclose(ifh); +} + +struct option lopt[] = { + {"syslog", 0, NULL, 's' }, + {"config-file", 1, NULL, 'c' }, + {"help", 0, NULL, '?' }, + {NULL}, +}; + +void usage(void) +{ + fprintf(stderr, _("usage: nameif [-c configurationfile] [-s] {ifname macaddress}")); + exit(1); +} + +int main(int ac, char **av) +{ + FILE *ifh; + char *p; + int n; + int linenum; + char *line = NULL; + size_t linel = 0; + + for (;;) { + int c = getopt_long(ac,av,"c:s",lopt,NULL); + if (c == -1) break; + switch (c) { + default: + case '?': + usage(); + case 'c': + fname = optarg; + break; + case 's': + use_syslog = 1; + break; + } + } + + if (use_syslog) + openlog("nameif",0,LOG_LOCAL0); + + while (optind < ac) { + struct change *ch = xmalloc(sizeof(struct change)); + char pos[30]; + + if ((ac-optind) & 1) + usage(); + if (strlen(av[optind])+1>IFNAMSIZ) + complain(_("interface name `%s' too long"), av[optind]); + strcpy(ch->ifname, av[optind]); + optind++; + sprintf(pos,_("argument %d"),optind); + addchange(av[optind], ch, pos); + optind++; + } + + if (!clist || fname != default_conf) + readconf(); + + ifh = fopen("/proc/net/dev", "r"); + if (!ifh) complain(_("open of /proc/net/dev: %s"), strerror(errno)); + + + linenum = 0; + while (getdelim(&line, &linel, '\n', ifh) > 0) { + struct change *ch; + unsigned char mac[6]; + + if (linenum++ < 2) + continue; + + p = line; + while (isspace(*p)) + ++p; + n = strcspn(p, ": \t"); + p[n] = 0; + + if (n > IFNAMSIZ-1) + complain(_("interface name `%s' too long"), p); + + if (getmac(p, mac) < 0) + continue; + + ch = lookupmac(mac); + if (!ch) + continue; + + *ch->pprev = ch->next; + if (strcmp(p, ch->ifname)) { + if (setname(p, ch->ifname) < 0) + complain(_("cannot change name of %s to %s: %s"), + p, ch->ifname, strerror(errno)); + } + free(ch); + } + fclose(ifh); + + while (clist) { + struct change *ch = clist; + clist = clist->next; + warning(_("interface '%s' not found"), ch->ifname); + free(ch); + } + + if (use_syslog) + closelog(); + return 0; +} + |