1 /* ifconfig.c - Configure network interface.
2  *
3  * Copyright 2012 Ranjan Kumar <ranjankumar.bth@gmail.com>
4  * Copyright 2012 Kyungwan Han <asura321@gamil.com>
5  * Reviewed by Kyungsu Kim <kaspyx@gmail.com>
6  *
7  * Not in SUSv4.
8 
9 USE_IFCONFIG(NEWTOY(ifconfig, "^?a", TOYFLAG_SBIN))
10 
11 config IFCONFIG
12   bool "ifconfig"
13   default y
14   help
15     usage: ifconfig [-a] [INTERFACE [ACTION...]]
16 
17     Display or configure network interface.
18 
19     With no arguments, display active interfaces. First argument is interface
20     to operate on, one argument by itself displays that interface.
21 
22     -a	Show all interfaces, not just active ones
23 
24     Additional arguments are actions to perform on the interface:
25 
26     ADDRESS[/NETMASK] - set IPv4 address (1.2.3.4/5)
27     default - unset ipv4 address
28     add|del ADDRESS[/PREFIXLEN] - add/remove IPv6 address (1111::8888/128)
29     up - enable interface
30     down - disable interface
31 
32     netmask|broadcast|pointopoint ADDRESS - set more IPv4 characteristics
33     hw ether|infiniband ADDRESS - set LAN hardware address (AA:BB:CC...)
34     txqueuelen LEN - number of buffered packets before output blocks
35     mtu LEN - size of outgoing packets (Maximum Transmission Unit)
36 
37     Flags you can set on an interface (or -remove by prefixing with -):
38     arp - don't use Address Resolution Protocol to map LAN routes
39     promisc - don't discard packets that aren't to this LAN hardware address
40     multicast - force interface into multicast mode if the driver doesn't
41     allmulti - promisc for multicast packets
42 
43     Obsolete fields included for historical purposes:
44     irq|io_addr|mem_start ADDR - micromanage obsolete hardware
45     outfill|keepalive INTEGER - SLIP analog dialup line quality monitoring
46     metric INTEGER - added to Linux 0.9.10 with comment "never used", still true
47 */
48 
49 #define FOR_ifconfig
50 #include "toys.h"
51 
52 #include <net/if_arp.h>
53 #include <net/ethernet.h>
54 
GLOBALS(int sockfd;)55 GLOBALS(
56   int sockfd;
57 )
58 
59 // Convert hostname to binary address for AF_INET or AF_INET6
60 // return /prefix (or range max if none)
61 int get_addrinfo(char *host, sa_family_t af, void *addr)
62 {
63   struct addrinfo hints, *result, *rp = 0;
64   int status, len;
65   char *from, *slash;
66 
67   memset(&hints, 0 , sizeof(struct addrinfo));
68   hints.ai_family = af;
69   hints.ai_socktype = SOCK_STREAM;
70 
71   slash = strchr(host, '/');
72   if (slash) *slash = 0;
73 
74   status = getaddrinfo(host, NULL, &hints, &result);
75   if (!status)
76     for (rp = result; rp; rp = rp->ai_next)
77       if (rp->ai_family == af) break;
78   if (!rp) error_exit("bad address '%s' : %s", host, gai_strerror(status));
79 
80   // ai_addr isn't struct in_addr or in6_addr, it's struct sockaddr. Of course.
81   // You'd think ipv4 and ipv6 would have some basic compatibility, but no.
82   from = ((char *)rp->ai_addr) + 4;
83   if (af == AF_INET6) {
84     len = 16;
85     from += 4;  // skip "flowinfo" field ipv6 puts before address
86   } else len = 4;
87   memcpy(addr, from, len);
88   freeaddrinfo(result);
89 
90   len = -1;
91   if (slash) len = atolx_range(slash+1, 0, (af == AF_INET) ? 32 : 128);
92 
93   return len;
94 }
95 
display_ifconfig(char * name,int always,unsigned long long val[])96 static void display_ifconfig(char *name, int always, unsigned long long val[])
97 {
98   struct ifreq ifre;
99   struct {
100     int type;
101     char *title;
102   } types[] = {
103     {ARPHRD_LOOPBACK, "Local Loopback"}, {ARPHRD_ETHER, "Ethernet"},
104     {ARPHRD_PPP, "Point-to-Point Protocol"}, {ARPHRD_INFINIBAND, "InfiniBand"},
105     {ARPHRD_SIT, "IPv6-in-IPv4"}, {-1, "UNSPEC"}
106   };
107   int i;
108   char *pp;
109   FILE *fp;
110   short flags;
111 
112   xstrncpy(ifre.ifr_name, name, IFNAMSIZ);
113   if (ioctl(TT.sockfd, SIOCGIFFLAGS, &ifre)<0) perror_exit_raw(name);
114   flags = ifre.ifr_flags;
115   if (!always && !(flags & IFF_UP)) return;
116 
117   // query hardware type and hardware address
118   i = ioctl(TT.sockfd, SIOCGIFHWADDR, &ifre);
119 
120   for (i=0; i < (sizeof(types)/sizeof(*types))-1; i++)
121     if (ifre.ifr_hwaddr.sa_family == types[i].type) break;
122 
123   xprintf("%-9s Link encap:%s  ", name, types[i].title);
124   if(i >= 0 && ifre.ifr_hwaddr.sa_family == ARPHRD_ETHER) {
125     xprintf("HWaddr ");
126     for (i=0; i<6; i++) xprintf(":%02x"+!i, ifre.ifr_hwaddr.sa_data[i]);
127   }
128   xputc('\n');
129 
130   // If an address is assigned record that.
131 
132   ifre.ifr_addr.sa_family = AF_INET;
133   memset(&ifre.ifr_addr, 0, sizeof(ifre.ifr_addr));
134   ioctl(TT.sockfd, SIOCGIFADDR, &ifre);
135   pp = (char *)&ifre.ifr_addr;
136   for (i = 0; i<sizeof(ifre.ifr_addr); i++) if (pp[i]) break;
137 
138   if (i != sizeof(ifre.ifr_addr)) {
139     struct sockaddr_in *si = (struct sockaddr_in *)&ifre.ifr_addr;
140     struct {
141       char *name;
142       int flag, ioctl;
143     } addr[] = {
144       {"addr", 0, 0},
145       {"P-t-P", IFF_POINTOPOINT, SIOCGIFDSTADDR},
146       {"Bcast", IFF_BROADCAST, SIOCGIFBRDADDR},
147       {"Mask", 0, SIOCGIFNETMASK}
148     };
149 
150     xprintf("%10c%s", ' ', (si->sin_family == AF_INET) ? "inet" :
151         (si->sin_family == AF_INET6) ? "inet6" : "unspec");
152 
153     for (i=0; i < sizeof(addr)/sizeof(*addr); i++) {
154       if (!addr[i].flag || (flags & addr[i].flag)) {
155         if (addr[i].ioctl && ioctl(TT.sockfd, addr[i].ioctl, &ifre))
156           si->sin_family = 0;
157         xprintf(" %s:%s ", addr[i].name,
158           (si->sin_family == 0xFFFF || !si->sin_family)
159             ? "[NOT SET]" : inet_ntoa(si->sin_addr));
160       }
161     }
162 
163     xputc('\n');
164   }
165 
166   fp = fopen(pp = "/proc/net/if_inet6", "r");
167   if (fp) {
168     char iface_name[IFNAMSIZ];
169     int plen, iscope;
170 
171     while (fgets(toybuf, sizeof(toybuf), fp)) {
172       int nitems;
173       char ipv6_addr[40];
174 
175       nitems = sscanf(toybuf, "%32s %*08x %02x %02x %*02x %15s\n",
176                       ipv6_addr, &plen, &iscope, iface_name);
177       if (nitems<0 && feof(fp)) break;
178       if (nitems != 4) perror_exit("bad %s", pp);
179 
180       if (!strcmp(name, iface_name)) {
181         struct sockaddr_in6 s6;
182         char *ptr = ipv6_addr+sizeof(ipv6_addr)-1;
183 
184         // convert giant hex string into colon-spearated ipv6 address by
185         // inserting ':' every 4 characters.
186         for (i = 32; i; i--)
187           if ((*(ptr--) = ipv6_addr[i])) if (!(i&3)) *(ptr--) = ':';
188 
189         // Convert to binary and back to get abbreviated :: version
190         if (inet_pton(AF_INET6, ipv6_addr, (void *)&s6.sin6_addr) > 0) {
191           if (inet_ntop(AF_INET6, &s6.sin6_addr, toybuf, sizeof(toybuf))) {
192             char *scopes[] = {"Global","Host","Link","Site","Compat"},
193                  *scope = "Unknown";
194 
195             for (i=0; i < sizeof(scopes)/sizeof(*scopes); i++)
196               if (iscope == (!!i)<<(i+3)) scope = scopes[i];
197             xprintf("%10cinet6 addr: %s/%d Scope: %s\n",
198                     ' ', toybuf, plen, scope);
199           }
200         }
201       }
202     }
203     fclose(fp);
204   }
205 
206   xprintf("%10c", ' ');
207 
208   if (flags) {
209     unsigned short mask = 1;
210     char **s, *str[] = {
211       "UP", "BROADCAST", "DEBUG", "LOOPBACK", "POINTOPOINT", "NOTRAILERS",
212       "RUNNING", "NOARP", "PROMISC", "ALLMULTI", "MASTER", "SLAVE", "MULTICAST",
213       "PORTSEL", "AUTOMEDIA", "DYNAMIC", NULL
214     };
215 
216     for (s = str; *s; s++) {
217       if (flags & mask) xprintf("%s ", *s);
218       mask = mask << 1;
219     }
220   } else xprintf("[NO FLAGS] ");
221 
222   if (ioctl(TT.sockfd, SIOCGIFMTU, &ifre) < 0) ifre.ifr_mtu = 0;
223   xprintf(" MTU:%d", ifre.ifr_mtu);
224   if (ioctl(TT.sockfd, SIOCGIFMETRIC, &ifre) < 0) ifre.ifr_metric = 0;
225   if (!ifre.ifr_metric) ifre.ifr_metric = 1;
226   xprintf("  Metric:%d", ifre.ifr_metric);
227 
228   // non-virtual interface
229 
230   if (val) {
231     char *label[] = {"RX bytes", "RX packets", "errors", "dropped", "overruns",
232       "frame", 0, 0, "TX bytes", "TX packets", "errors", "dropped", "overruns",
233       "collisions", "carrier", 0, "txqueuelen"};
234     signed char order[] = {-1, 1, 2, 3, 4, 5, -1, 9, 10, 11, 12, 14, -1,
235       13, 16, -1, 0, 8};
236     int i;
237 
238     // Query txqueuelen
239     if (ioctl(TT.sockfd, SIOCGIFTXQLEN, &ifre) >= 0) val[16] = ifre.ifr_qlen;
240     else val[16] = -1;
241 
242     for (i = 0; i < sizeof(order); i++) {
243       int j = order[i];
244 
245       if (j < 0) xprintf("\n%10c", ' ');
246       else xprintf("%s:%llu ", label[j], val[j]);
247     }
248   }
249   xputc('\n');
250 
251   if(!ioctl(TT.sockfd, SIOCGIFMAP, &ifre) && (ifre.ifr_map.irq ||
252       ifre.ifr_map.mem_start || ifre.ifr_map.dma || ifre.ifr_map.base_addr))
253   {
254     xprintf("%10c", ' ');
255     if(ifre.ifr_map.irq) xprintf("Interrupt:%d ", ifre.ifr_map.irq);
256     if(ifre.ifr_map.base_addr >= 0x100) // IO_MAP_INDEX
257       xprintf("Base address:0x%x ", ifre.ifr_map.base_addr);
258     if(ifre.ifr_map.mem_start)
259       xprintf("Memory:%lx-%lx ", ifre.ifr_map.mem_start, ifre.ifr_map.mem_end);
260     if(ifre.ifr_map.dma) xprintf("DMA chan:%x ", ifre.ifr_map.dma);
261     xputc('\n');
262   }
263   xputc('\n');
264 }
265 
show_iface(char * iface_name)266 static void show_iface(char *iface_name)
267 {
268   char *name;
269   struct string_list *ifaces = 0, *sl;
270   int i, j;
271   FILE *fp;
272 
273   fp = xfopen("/proc/net/dev", "r");
274 
275   for (i=0; fgets(toybuf, sizeof(toybuf), fp); i++) {
276     char *buf = toybuf;
277     unsigned long long val[17];
278 
279     if (i<2) continue;
280 
281     while (isspace(*buf)) buf++;
282     name = strsep(&buf, ":");
283     if(!buf) error_exit("bad name %s", name);
284 
285     errno = 0;
286     for (j=0; j<16 && !errno; j++) val[j] = strtoll(buf, &buf, 0);
287     if (errno) perror_exit("bad %s at %s", name, buf);
288 
289     if (iface_name) {
290       if (!strcmp(iface_name, name)) {
291         display_ifconfig(iface_name, 1, val);
292 
293         return;
294       }
295     } else {
296       sl = xmalloc(sizeof(*sl)+strlen(name)+1);
297       strcpy(sl->str, name);
298       sl->next = ifaces;
299       ifaces = sl;
300 
301       display_ifconfig(sl->str, toys.optflags & FLAG_a, val);
302     }
303   }
304   fclose(fp);
305 
306   if (iface_name) display_ifconfig(iface_name, 1, 0);
307   else {
308     struct ifconf ifcon;
309     struct ifreq *ifre;
310     int num;
311 
312     // Loop until buffer's big enough
313     ifcon.ifc_buf = NULL;
314     for (num = 30;;num += 10) {
315       ifcon.ifc_len = sizeof(struct ifreq)*num;
316       ifcon.ifc_buf = xrealloc(ifcon.ifc_buf, ifcon.ifc_len);
317       xioctl(TT.sockfd, SIOCGIFCONF, &ifcon);
318       if (ifcon.ifc_len != sizeof(struct ifreq)*num) break;
319     }
320 
321     ifre = ifcon.ifc_req;
322     for(num = 0; num < ifcon.ifc_len && ifre; num += sizeof(struct ifreq), ifre++)
323     {
324       // Skip duplicates
325       for(sl = ifaces; sl; sl = sl->next)
326         if(!strcmp(sl->str, ifre->ifr_name)) break;
327 
328       if(!sl) display_ifconfig(ifre->ifr_name, toys.optflags & FLAG_a, 0);
329     }
330 
331     free(ifcon.ifc_buf);
332   }
333 
334   llist_traverse(ifaces, free);
335 }
336 
337 // Encode offset and size of field into an int, and make result negative
338 #define IFREQ_OFFSZ(x) -(int)((offsetof(struct ifreq, x)<<16) + sizeof(ifre.x))
339 
ifconfig_main(void)340 void ifconfig_main(void)
341 {
342   char **argv = toys.optargs;
343   struct ifreq ifre;
344   int i;
345 
346   TT.sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);
347   if(toys.optc < 2) {
348     show_iface(*argv);
349     return;
350   }
351 
352   // Open interface
353   memset(&ifre, 0, sizeof(struct ifreq));
354   xstrncpy(ifre.ifr_name, *argv, IFNAMSIZ);
355 
356   // Perform operations on interface
357   while(*++argv) {
358     // Table of known operations
359     struct argh {
360       char *name;
361       int on, off; // set, clear
362     } try[] = {
363       {0, IFF_UP|IFF_RUNNING, SIOCSIFADDR},
364       {"up", IFF_UP|IFF_RUNNING, 0},
365       {"down", 0, IFF_UP},
366       {"arp", 0, IFF_NOARP},
367       {"promisc", IFF_PROMISC, 0},
368       {"allmulti", IFF_ALLMULTI, 0},
369       {"multicast", IFF_MULTICAST, 0},
370       {"pointopoint", IFF_POINTOPOINT, SIOCSIFDSTADDR},
371       {"broadcast", IFF_BROADCAST, SIOCSIFBRDADDR},
372       {"netmask", 0, SIOCSIFNETMASK},
373       {"dstaddr", 0, SIOCSIFDSTADDR},
374       {"mtu", IFREQ_OFFSZ(ifr_mtu), SIOCSIFMTU},
375       {"keepalive", IFREQ_OFFSZ(ifr_data), SIOCDEVPRIVATE}, // SIOCSKEEPALIVE
376       {"outfill", IFREQ_OFFSZ(ifr_data), SIOCDEVPRIVATE+2}, // SIOCSOUTFILL
377       {"metric", IFREQ_OFFSZ(ifr_metric), SIOCSIFMETRIC},
378       {"txqueuelen", IFREQ_OFFSZ(ifr_qlen), SIOCSIFTXQLEN},
379       {"mem_start", IFREQ_OFFSZ(ifr_map.mem_start), SIOCSIFMAP},
380       {"io_addr", IFREQ_OFFSZ(ifr_map.base_addr), SIOCSIFMAP},
381       {"irq", IFREQ_OFFSZ(ifr_map.irq), SIOCSIFMAP},
382       {"inet", 0, 0},
383       {"inet6", 0, 0}
384     };
385     char *s = *argv;
386     int rev = (*s == '-');
387 
388     s += rev;
389 
390     // "set hardware address" is oddball enough to special case
391     if (!strcmp(*argv, "hw")) {
392       char *hw_addr, *ptr, *p;
393       struct sockaddr *sock = &ifre.ifr_hwaddr;
394       int count = 6;
395 
396       ptr = p = (char *)sock->sa_data;
397       memset(sock, 0, sizeof(struct sockaddr));
398       if (argv[1]) {
399         if (!strcmp("ether", *++argv)) sock->sa_family = ARPHRD_ETHER;
400         else if (!strcmp("infiniband", *argv)) {
401           sock->sa_family = ARPHRD_INFINIBAND;
402           count = 20;
403           p = ptr = toybuf;
404         }
405       }
406       if (!sock->sa_family || !argv[1]) help_exit("bad hw '%s'", *argv);
407       hw_addr = *++argv;
408 
409       // Parse and verify address.
410       while (*hw_addr && (p-ptr) < count) {
411         int val, len = 0;
412 
413         if (*hw_addr == ':') hw_addr++;
414         sscanf(hw_addr, "%2x%n", &val, &len);
415         if (!len || len > 2) break; // 1 nibble can be set e.g. C2:79:38:95:D:A
416         hw_addr += len;
417         *p++ = val;
418       }
419 
420       if ((p-ptr) != count || *hw_addr)
421         error_exit("bad hw-addr '%s'", *argv);
422 
423       // the linux kernel's "struct sockaddr" (include/linux/socket.h in the
424       // kernel source) only has 14 bytes of sa_data, and an infiniband address
425       // is 20. So if we go through the ioctl, the kernel will truncate
426       // infiniband addresses, meaning we have to go through sysfs instead.
427       if (sock->sa_family == ARPHRD_INFINIBAND && !strchr(ifre.ifr_name, '/')) {
428         int fd;
429 
430         sprintf(toybuf, "/sys/class/net/%s/address", ifre.ifr_name);
431         fd = xopen(toybuf, O_RDWR);
432         xwrite(fd, *argv, strlen(*argv));
433         close(fd);
434       } else xioctl(TT.sockfd, SIOCSIFHWADDR, &ifre);
435       continue;
436 
437     // Add/remove ipv6 address to interface
438 
439     } else if (!strcmp(*argv, "add") || !strcmp(*argv, "del")) {
440       struct ifreq_inet6 {
441         struct in6_addr addr;
442         unsigned prefix;
443         int index;
444       } ifre6;
445       int plen, fd6 = xsocket(AF_INET6, SOCK_DGRAM, 0);
446 
447       if (!argv[1]) help_exit("%s", *argv);
448 
449       plen = get_addrinfo(argv[1], AF_INET6, &ifre6.addr);
450       if (plen < 0) plen = 128;
451       xioctl(fd6, SIOCGIFINDEX, &ifre);
452       ifre6.index = ifre.ifr_ifindex;
453       ifre6.prefix = plen;
454       xioctl(fd6, **(argv++)=='a' ? SIOCSIFADDR : SIOCDIFADDR, &ifre6);
455 
456       close(fd6);
457       continue;
458     // Iterate through table to find/perform operation
459     } else for (i = 0; i < ARRAY_LEN(try); i++) {
460       struct argh *t = try+i;
461       int on = t->on, off = t->off;
462 
463       if (!t->name) {
464         if (isdigit(**argv) || !strcmp(*argv, "default")) argv--;
465         else continue;
466       } else if (strcmp(t->name, s)) continue;
467 
468       // Is this an SIOCSI entry?
469       if ((off|0xff) == 0x89ff) {
470         if (!rev) {
471           if (!*++argv) error_exit("%s needs argument", t->name);
472 
473           // Assign value to ifre field and call ioctl? (via IFREQ_OFFSZ.)
474           if (on < 0) {
475             long l = strtoul(*argv, 0, 0);
476 
477             if (off == SIOCSIFMAP) xioctl(TT.sockfd, SIOCGIFMAP, &ifre);
478             on = -on;
479             poke((on>>16) + (char *)&ifre, l, on&15);
480             xioctl(TT.sockfd, off, &ifre);
481             break;
482           } else {
483             struct sockaddr_in *si = (struct sockaddr_in *)&ifre.ifr_addr;
484             int mask = -1;
485 
486             si->sin_family = AF_INET;
487 
488             if (!strcmp(*argv, "default")) si->sin_addr.s_addr = INADDR_ANY;
489             else mask = get_addrinfo(*argv, AF_INET, &si->sin_addr);
490             xioctl(TT.sockfd, off, &ifre);
491 
492             // Handle /netmask
493             if (mask >= 0) {
494               // sin_addr probably isn't unaligned, but just in case...
495               mask = htonl((~0)<<(32-mask));
496               memcpy(&si->sin_addr, &mask, 4);
497               xioctl(TT.sockfd, SIOCSIFNETMASK, &ifre);
498             }
499           }
500         }
501         off = 0;
502       }
503 
504       // Set flags
505       if (on || off) {
506         xioctl(TT.sockfd, SIOCGIFFLAGS, &ifre);
507         ifre.ifr_flags &= ~(rev ? on : off);
508         ifre.ifr_flags |= (rev ? off : on);
509         xioctl(TT.sockfd, SIOCSIFFLAGS, &ifre);
510       }
511 
512       break;
513     }
514     if (i == sizeof(try)/sizeof(*try)) help_exit("bad argument '%s'", *argv);
515   }
516   close(TT.sockfd);
517 }
518