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  * Obsolete fields included for historical purposes:
10  * irq|io_addr|mem_start ADDR - micromanage obsolete hardware
11  * outfill|keepalive INTEGER - SLIP analog dialup line quality monitoring
12  * metric INTEGER - added to Linux 0.9.10 with comment "never used", still true
13 
14 USE_IFCONFIG(NEWTOY(ifconfig, "^?aS", TOYFLAG_SBIN))
15 
16 config IFCONFIG
17   bool "ifconfig"
18   default y
19   help
20     usage: ifconfig [-aS] [INTERFACE [ACTION...]]
21 
22     Display or configure network interface.
23 
24     With no arguments, display active interfaces. First argument is interface
25     to operate on, one argument by itself displays that interface.
26 
27     -a	All interfaces displayed, not just active ones
28     -S	Short view, one line per interface
29 
30     Standard ACTIONs to perform on an INTERFACE:
31 
32     ADDR[/MASK]        - set IPv4 address (1.2.3.4/5) and activate interface
33     add|del ADDR[/LEN] - add/remove IPv6 address (1111::8888/128)
34     up|down            - activate or deactivate interface
35 
36     Advanced ACTIONs (default values usually suffice):
37 
38     default          - remove IPv4 address
39     netmask ADDR     - set IPv4 netmask via 255.255.255.0 instead of /24
40     txqueuelen LEN   - number of buffered packets before output blocks
41     mtu LEN          - size of outgoing packets (Maximum Transmission Unit)
42     broadcast ADDR   - Set broadcast address
43     pointopoint ADDR - PPP and PPPOE use this instead of "route add default gw"
44     hw TYPE ADDR     - set hardware (mac) address (type = ether|infiniband)
45 
46     Flags you can set on an interface (or -remove by prefixing with -):
47 
48     arp       - don't use Address Resolution Protocol to map LAN routes
49     promisc   - don't discard packets that aren't to this LAN hardware address
50     multicast - force interface into multicast mode if the driver doesn't
51     allmulti  - promisc for multicast packets
52 */
53 
54 #define FOR_ifconfig
55 #include "toys.h"
56 
57 #include <net/if_arp.h>
58 #include <net/ethernet.h>
59 
GLOBALS(int sockfd;)60 GLOBALS(
61   int sockfd;
62 )
63 
64 // Convert hostname to binary address for AF_INET or AF_INET6
65 // return /prefix (or range max if none)
66 static int get_addrinfo(char *host, sa_family_t af, void *addr)
67 {
68   struct addrinfo hints, *result, *rp = 0;
69   int status, len;
70   char *from, *slash;
71 
72   memset(&hints, 0 , sizeof(struct addrinfo));
73   hints.ai_family = af;
74   hints.ai_socktype = SOCK_STREAM;
75 
76   slash = strchr(host, '/');
77   if (slash) *slash = 0;
78 
79   status = getaddrinfo(host, NULL, &hints, &result);
80   if (!status)
81     for (rp = result; rp; rp = rp->ai_next)
82       if (rp->ai_family == af) break;
83   if (!rp) error_exit("bad address '%s' : %s", host, gai_strerror(status));
84 
85   // ai_addr isn't struct in_addr or in6_addr, it's struct sockaddr. Of course.
86   // You'd think ipv4 and ipv6 would have some basic compatibility, but no.
87   from = ((char *)rp->ai_addr) + 4;
88   if (af == AF_INET6) {
89     len = 16;
90     from += 4;  // skip "flowinfo" field ipv6 puts before address
91   } else len = 4;
92   memcpy(addr, from, len);
93   freeaddrinfo(result);
94 
95   len = -1;
96   if (slash) len = atolx_range(slash+1, 0, (af == AF_INET) ? 32 : 128);
97 
98   return len;
99 }
100 
display_ifconfig(char * name,int always,unsigned long long val[])101 static void display_ifconfig(char *name, int always, unsigned long long val[])
102 {
103   struct ifreq ifre;
104   struct sockaddr_in *si = (void *)&ifre.ifr_addr;
105   struct {
106     int type;
107     char *title;
108   } types[] = {
109     {ARPHRD_LOOPBACK, "Local Loopback"}, {ARPHRD_ETHER, "Ethernet"},
110     {ARPHRD_PPP, "Point-to-Point Protocol"}, {ARPHRD_INFINIBAND, "InfiniBand"},
111     {ARPHRD_SIT, "IPv6-in-IPv4"}, {-1, "UNSPEC"}
112   };
113   int i;
114   char *pp;
115   FILE *fp;
116   short flags;
117 
118   xstrncpy(ifre.ifr_name, name, IFNAMSIZ);
119   if (ioctl(TT.sockfd, SIOCGIFFLAGS, &ifre)<0) perror_exit_raw(name);
120   flags = ifre.ifr_flags;
121   if (!always && !(flags & IFF_UP)) return;
122 
123   if (toys.optflags&FLAG_S) {
124     unsigned uu = 0;
125     int len;
126 
127     ioctl(TT.sockfd, SIOCGIFADDR, &ifre);
128     len = printf("%*s %s", -9, name, inet_ntoa(si->sin_addr));
129     if (!ioctl(TT.sockfd, SIOCGIFNETMASK, &ifre))
130       uu = htonl(*(unsigned *)&(si->sin_addr));
131     for (i = 0; uu; i++) uu <<= 1;
132     len += printf("/%d", i);
133     printf("%*c", 29-len, ' ');
134   }
135 
136   // query hardware type and hardware address
137   xioctl(TT.sockfd, SIOCGIFHWADDR, &ifre);
138 
139   if (toys.optflags&FLAG_S)
140     for (i=0; i<6; i++) printf(":%02x"+!i, ifre.ifr_hwaddr.sa_data[i]);
141   else {
142     for (i=0; i < ARRAY_LEN(types)-1; i++)
143       if (ifre.ifr_hwaddr.sa_family == types[i].type) break;
144     xprintf("%-9s Link encap:%s  ", name, types[i].title);
145     if(ifre.ifr_hwaddr.sa_family == ARPHRD_ETHER) {
146       xprintf("HWaddr ");
147       for (i=0; i<6; i++) xprintf(":%02x"+!i, ifre.ifr_hwaddr.sa_data[i]);
148     }
149     sprintf(toybuf, "/sys/class/net/%.15s/device/driver", name);
150     if (readlink0(toybuf, toybuf, sizeof(toybuf))>0)
151       if ((pp = strrchr(toybuf, '/'))) xprintf("  Driver %s", pp+1);
152     xputc('\n');
153   }
154 
155   // If an address is assigned record that.
156 
157   ifre.ifr_addr.sa_family = AF_INET;
158   memset(&ifre.ifr_addr, 0, sizeof(ifre.ifr_addr));
159   ioctl(TT.sockfd, SIOCGIFADDR, &ifre);
160   pp = (char *)&ifre.ifr_addr;
161   for (i = 0; i<sizeof(ifre.ifr_addr); i++) if (pp[i]) break;
162 
163   if (!(toys.optflags&FLAG_S) && i != sizeof(ifre.ifr_addr)) {
164     struct sockaddr_in *si = (struct sockaddr_in *)&ifre.ifr_addr;
165     struct {
166       char *name;
167       int flag, ioctl;
168     } addr[] = {
169       {"addr", 0, 0},
170       {"P-t-P", IFF_POINTOPOINT, SIOCGIFDSTADDR},
171       {"Bcast", IFF_BROADCAST, SIOCGIFBRDADDR},
172       {"Mask", 0, SIOCGIFNETMASK}
173     };
174 
175     // TODO: can this be ipv6? Why are we checking here when ipv6 source later?
176     xprintf("%10c%s", ' ', (si->sin_family == AF_INET) ? "inet" :
177         (si->sin_family == AF_INET6) ? "inet6" : "unspec");
178 
179     for (i=0; i<ARRAY_LEN(addr); i++) {
180       if (!addr[i].flag || (flags & addr[i].flag)) {
181         if (addr[i].ioctl && ioctl(TT.sockfd, addr[i].ioctl, &ifre))
182           si->sin_family = 0;
183         xprintf(" %s:%s ", addr[i].name,
184           (si->sin_family == 0xFFFF || !si->sin_family)
185             ? "[NOT SET]" : inet_ntoa(si->sin_addr));
186       }
187     }
188 
189     xputc('\n');
190   }
191 
192   fp = fopen(pp = "/proc/net/if_inet6", "r");
193   if (fp) {
194     char iface_name[IFNAMSIZ];
195     int plen, iscope;
196 
197     while (fgets(toybuf, sizeof(toybuf), fp)) {
198       int nitems;
199       char ipv6_addr[40];
200 
201       nitems = sscanf(toybuf, "%32s %*08x %02x %02x %*02x %15s\n",
202                       ipv6_addr, &plen, &iscope, iface_name);
203       if (nitems<0 && feof(fp)) break;
204       if (nitems != 4) perror_exit("bad %s", pp);
205 
206       if (!strcmp(name, iface_name)) {
207         struct sockaddr_in6 s6;
208         char *ptr = ipv6_addr+sizeof(ipv6_addr)-1;
209 
210         // convert giant hex string into colon-spearated ipv6 address by
211         // inserting ':' every 4 characters.
212         for (i = 32; i; i--)
213           if ((*(ptr--) = ipv6_addr[i])) if (!(i&3)) *(ptr--) = ':';
214 
215         // Convert to binary and back to get abbreviated :: version
216         if (inet_pton(AF_INET6, ipv6_addr, (void *)&s6.sin6_addr) > 0) {
217           if (inet_ntop(AF_INET6, &s6.sin6_addr, toybuf, sizeof(toybuf))) {
218             char *scopes[] = {"Global","Host","Link","Site","Compat"},
219                  *scope = "Unknown";
220 
221             for (i=0; i<ARRAY_LEN(scopes); i++)
222               if (iscope == (!!i)<<(i+3)) scope = scopes[i];
223             if (toys.optflags&FLAG_S) xprintf(" %s/%d@%c", toybuf, plen,*scope);
224             else xprintf("%10cinet6 addr: %s/%d Scope: %s\n",
225                          ' ', toybuf, plen, scope);
226           }
227         }
228       }
229     }
230     fclose(fp);
231   }
232 
233   if (toys.optflags&FLAG_S) {
234     xputc('\n');
235     return;
236   }
237 
238   xprintf("%10c", ' ');
239 
240   if (flags) {
241     unsigned short mask = 1;
242     char **s, *str[] = {
243       "UP", "BROADCAST", "DEBUG", "LOOPBACK", "POINTOPOINT", "NOTRAILERS",
244       "RUNNING", "NOARP", "PROMISC", "ALLMULTI", "MASTER", "SLAVE", "MULTICAST",
245       "PORTSEL", "AUTOMEDIA", "DYNAMIC", NULL
246     };
247 
248     for (s = str; *s; s++) {
249       if (flags & mask) xprintf("%s ", *s);
250       mask = mask << 1;
251     }
252   } else xprintf("[NO FLAGS] ");
253 
254   if (ioctl(TT.sockfd, SIOCGIFMTU, &ifre) < 0) ifre.ifr_mtu = 0;
255   xprintf(" MTU:%d", ifre.ifr_mtu);
256   if (ioctl(TT.sockfd, SIOCGIFMETRIC, &ifre) < 0) ifre.ifr_metric = 0;
257   if (!ifre.ifr_metric) ifre.ifr_metric = 1;
258   xprintf("  Metric:%d", ifre.ifr_metric);
259 
260   // non-virtual interface
261 
262   if (val) {
263     char *label[] = {"RX bytes", "RX packets", "errors", "dropped", "overruns",
264       "frame", 0, 0, "TX bytes", "TX packets", "errors", "dropped", "overruns",
265       "collisions", "carrier", 0, "txqueuelen"};
266     signed char order[] = {-1, 1, 2, 3, 4, 5, -1, 9, 10, 11, 12, 14, -1,
267       13, 16, -1, 0, 8};
268     int i;
269 
270     // Query txqueuelen
271     if (ioctl(TT.sockfd, SIOCGIFTXQLEN, &ifre) >= 0) val[16] = ifre.ifr_qlen;
272     else val[16] = -1;
273 
274     for (i = 0; i<sizeof(order); i++) {
275       int j = order[i];
276 
277       if (j < 0) xprintf("\n%10c", ' ');
278       else xprintf("%s:%llu ", label[j], val[j]);
279     }
280   }
281   xputc('\n');
282 
283   if(!ioctl(TT.sockfd, SIOCGIFMAP, &ifre) && (ifre.ifr_map.irq ||
284       ifre.ifr_map.mem_start || ifre.ifr_map.dma || ifre.ifr_map.base_addr))
285   {
286     xprintf("%10c", ' ');
287     if(ifre.ifr_map.irq) xprintf("Interrupt:%d ", ifre.ifr_map.irq);
288     if(ifre.ifr_map.base_addr >= 0x100) // IO_MAP_INDEX
289       xprintf("Base address:0x%x ", ifre.ifr_map.base_addr);
290     if(ifre.ifr_map.mem_start)
291       xprintf("Memory:%lx-%lx ", ifre.ifr_map.mem_start, ifre.ifr_map.mem_end);
292     if(ifre.ifr_map.dma) xprintf("DMA chan:%x ", ifre.ifr_map.dma);
293     xputc('\n');
294   }
295   xputc('\n');
296 }
297 
show_iface(char * iface_name)298 static void show_iface(char *iface_name)
299 {
300   char *name;
301   struct string_list *ifaces = 0, *sl;
302   int i, j;
303   FILE *fp;
304 
305   fp = xfopen("/proc/net/dev", "r");
306 
307   for (i=0; fgets(toybuf, sizeof(toybuf), fp); i++) {
308     char *buf = toybuf;
309     unsigned long long val[17];
310 
311     if (i<2) continue;
312 
313     while (isspace(*buf)) buf++;
314     name = strsep(&buf, ":");
315     if(!buf) error_exit("bad name %s", name);
316 
317     errno = 0;
318     for (j=0; j<16 && !errno; j++) val[j] = strtoll(buf, &buf, 0);
319     if (errno) perror_exit("bad %s at %s", name, buf);
320 
321     if (iface_name) {
322       if (!strcmp(iface_name, name)) {
323         display_ifconfig(iface_name, 1, val);
324 
325         return;
326       }
327     } else {
328       sl = xmalloc(sizeof(*sl)+strlen(name)+1);
329       strcpy(sl->str, name);
330       sl->next = ifaces;
331       ifaces = sl;
332 
333       display_ifconfig(sl->str, toys.optflags & FLAG_a, val);
334     }
335   }
336   fclose(fp);
337 
338   if (iface_name) display_ifconfig(iface_name, 1, 0);
339   else {
340     struct ifconf ifcon;
341     struct ifreq *ifre;
342     int num;
343 
344     // Loop until buffer's big enough
345     ifcon.ifc_buf = NULL;
346     for (num = 30;;num += 10) {
347       ifcon.ifc_len = sizeof(struct ifreq)*num;
348       ifcon.ifc_buf = xrealloc(ifcon.ifc_buf, ifcon.ifc_len);
349       xioctl(TT.sockfd, SIOCGIFCONF, &ifcon);
350       if (ifcon.ifc_len != sizeof(struct ifreq)*num) break;
351     }
352 
353     ifre = ifcon.ifc_req;
354     for(num = 0; num < ifcon.ifc_len && ifre; num += sizeof(struct ifreq), ifre++)
355     {
356       // Skip duplicates
357       for(sl = ifaces; sl; sl = sl->next)
358         if(!strcmp(sl->str, ifre->ifr_name)) break;
359 
360       if(!sl) display_ifconfig(ifre->ifr_name, toys.optflags & FLAG_a, 0);
361     }
362 
363     free(ifcon.ifc_buf);
364   }
365 
366   llist_traverse(ifaces, free);
367 }
368 
369 // Encode offset and size of field into an int, and make result negative
370 #define IFREQ_OFFSZ(x) -(int)((offsetof(struct ifreq, x)<<16) + sizeof(ifre.x))
371 
ifconfig_main(void)372 void ifconfig_main(void)
373 {
374   char **argv = toys.optargs;
375   struct ifreq ifre;
376   int i;
377 
378   TT.sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);
379   if(toys.optc < 2) {
380     show_iface(*argv);
381     return;
382   }
383 
384   // Open interface
385   memset(&ifre, 0, sizeof(struct ifreq));
386   xstrncpy(ifre.ifr_name, *argv, IFNAMSIZ);
387 
388   // Perform operations on interface
389   while(*++argv) {
390     // Table of known operations
391     struct argh {
392       char *name;
393       int on, off; // set, clear
394     } try[] = {
395       {0, IFF_UP|IFF_RUNNING, SIOCSIFADDR},
396       {"up", IFF_UP|IFF_RUNNING, 0},
397       {"down", 0, IFF_UP},
398       {"arp", 0, IFF_NOARP},
399       {"promisc", IFF_PROMISC, 0},
400       {"allmulti", IFF_ALLMULTI, 0},
401       {"multicast", IFF_MULTICAST, 0},
402       {"pointopoint", IFF_POINTOPOINT, SIOCSIFDSTADDR},
403       {"broadcast", IFF_BROADCAST, SIOCSIFBRDADDR},
404       {"netmask", 0, SIOCSIFNETMASK},
405       {"dstaddr", 0, SIOCSIFDSTADDR},
406       {"mtu", IFREQ_OFFSZ(ifr_mtu), SIOCSIFMTU},
407       {"keepalive", IFREQ_OFFSZ(ifr_data), SIOCDEVPRIVATE}, // SIOCSKEEPALIVE
408       {"outfill", IFREQ_OFFSZ(ifr_data), SIOCDEVPRIVATE+2}, // SIOCSOUTFILL
409       {"metric", IFREQ_OFFSZ(ifr_metric), SIOCSIFMETRIC},
410       {"txqueuelen", IFREQ_OFFSZ(ifr_qlen), SIOCSIFTXQLEN},
411       {"mem_start", IFREQ_OFFSZ(ifr_map.mem_start), SIOCSIFMAP},
412       {"io_addr", IFREQ_OFFSZ(ifr_map.base_addr), SIOCSIFMAP},
413       {"irq", IFREQ_OFFSZ(ifr_map.irq), SIOCSIFMAP},
414       {"inet", 0, 0},
415       {"inet6", 0, 0}
416     };
417     char *s = *argv;
418     int rev = (*s == '-');
419 
420     s += rev;
421 
422     // "set hardware address" is oddball enough to special case
423     if (!strcmp(*argv, "hw")) {
424       char *hw_addr, *ptr, *p;
425       struct sockaddr *sock = &ifre.ifr_hwaddr;
426       int count = 6;
427 
428       ptr = p = (char *)sock->sa_data;
429       memset(sock, 0, sizeof(struct sockaddr));
430       if (argv[1]) {
431         if (!strcmp("ether", *++argv)) sock->sa_family = ARPHRD_ETHER;
432         else if (!strcmp("infiniband", *argv)) {
433           sock->sa_family = ARPHRD_INFINIBAND;
434           count = 20;
435           p = ptr = toybuf;
436         }
437       }
438       if (!sock->sa_family || !argv[1]) help_exit("bad hw '%s'", *argv);
439       hw_addr = *++argv;
440 
441       // Parse and verify address.
442       while (*hw_addr && (p-ptr) < count) {
443         int val, len = 0;
444 
445         if (*hw_addr == ':') hw_addr++;
446         sscanf(hw_addr, "%2x%n", &val, &len);
447         if (!len || len > 2) break; // 1 nibble can be set e.g. C2:79:38:95:D:A
448         hw_addr += len;
449         *p++ = val;
450       }
451 
452       if ((p-ptr) != count || *hw_addr)
453         error_exit("bad hw-addr '%s'", *argv);
454 
455       // the linux kernel's "struct sockaddr" (include/linux/socket.h in the
456       // kernel source) only has 14 bytes of sa_data, and an infiniband address
457       // is 20. So if we go through the ioctl, the kernel will truncate
458       // infiniband addresses, meaning we have to go through sysfs instead.
459       if (sock->sa_family == ARPHRD_INFINIBAND && !strchr(ifre.ifr_name, '/')) {
460         int fd;
461 
462         sprintf(toybuf, "/sys/class/net/%s/address", ifre.ifr_name);
463         fd = xopen(toybuf, O_RDWR);
464         xwrite(fd, *argv, strlen(*argv));
465         close(fd);
466       } else xioctl(TT.sockfd, SIOCSIFHWADDR, &ifre);
467       continue;
468 
469     // Add/remove ipv6 address to interface
470 
471     } else if (!strcmp(*argv, "add") || !strcmp(*argv, "del")) {
472       struct ifreq_inet6 {
473         struct in6_addr addr;
474         unsigned prefix;
475         int index;
476       } ifre6;
477       int plen, fd6 = xsocket(AF_INET6, SOCK_DGRAM, 0);
478 
479       if (!argv[1]) help_exit("%s", *argv);
480 
481       plen = get_addrinfo(argv[1], AF_INET6, &ifre6.addr);
482       if (plen < 0) plen = 128;
483       xioctl(fd6, SIOCGIFINDEX, &ifre);
484       ifre6.index = ifre.ifr_ifindex;
485       ifre6.prefix = plen;
486       xioctl(fd6, **(argv++)=='a' ? SIOCSIFADDR : SIOCDIFADDR, &ifre6);
487 
488       close(fd6);
489       continue;
490     // Iterate through table to find/perform operation
491     } else for (i = 0; i<ARRAY_LEN(try); i++) {
492       struct argh *t = try+i;
493       int on = t->on, off = t->off;
494 
495       if (!t->name) {
496         if (isdigit(**argv) || !strcmp(*argv, "default")) argv--;
497         else continue;
498       } else if (strcmp(t->name, s)) continue;
499 
500       // Is this an SIOCSI entry?
501       if ((off|0xff) == 0x89ff) {
502         if (!rev) {
503           if (!*++argv) error_exit("%s needs argument", t->name);
504 
505           // Assign value to ifre field and call ioctl? (via IFREQ_OFFSZ.)
506           if (on < 0) {
507             long l = strtoul(*argv, 0, 0);
508 
509             if (off == SIOCSIFMAP) xioctl(TT.sockfd, SIOCGIFMAP, &ifre);
510             on = -on;
511             poke((on>>16) + (char *)&ifre, l, on&15);
512             xioctl(TT.sockfd, off, &ifre);
513             break;
514           } else {
515             struct sockaddr_in *si = (struct sockaddr_in *)&ifre.ifr_addr;
516             int mask = -1;
517 
518             si->sin_family = AF_INET;
519 
520             if (!strcmp(*argv, "default")) si->sin_addr.s_addr = INADDR_ANY;
521             else mask = get_addrinfo(*argv, AF_INET, &si->sin_addr);
522             xioctl(TT.sockfd, off, &ifre);
523 
524             // Handle /netmask
525             if (mask >= 0) {
526               // sin_addr probably isn't unaligned, but just in case...
527               mask = htonl((~0)<<(32-mask));
528               memcpy(&si->sin_addr, &mask, 4);
529               xioctl(TT.sockfd, SIOCSIFNETMASK, &ifre);
530             }
531           }
532         }
533         off = 0;
534       }
535 
536       // Set flags
537       if (on || off) {
538         xioctl(TT.sockfd, SIOCGIFFLAGS, &ifre);
539         ifre.ifr_flags &= ~(rev ? on : off);
540         ifre.ifr_flags |= (rev ? off : on);
541         xioctl(TT.sockfd, SIOCSIFFLAGS, &ifre);
542       }
543 
544       break;
545     }
546     if (i == ARRAY_LEN(try)) help_exit("bad argument '%s'", *argv);
547   }
548   close(TT.sockfd);
549 }
550