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   // Not xioctl because you don't have permission for this on Android.
138   ioctl(TT.sockfd, SIOCGIFHWADDR, &ifre);
139 
140   if (toys.optflags&FLAG_S)
141     for (i=0; i<6; i++) printf(":%02x"+!i, ifre.ifr_hwaddr.sa_data[i]);
142   else {
143     for (i=0; i < ARRAY_LEN(types)-1; i++)
144       if (ifre.ifr_hwaddr.sa_family == types[i].type) break;
145     xprintf("%-9s Link encap:%s  ", name, types[i].title);
146     if(ifre.ifr_hwaddr.sa_family == ARPHRD_ETHER) {
147       xprintf("HWaddr ");
148       for (i=0; i<6; i++) xprintf(":%02x"+!i, ifre.ifr_hwaddr.sa_data[i]);
149     }
150     sprintf(toybuf, "/sys/class/net/%.15s/device/driver", name);
151     if (readlink0(toybuf, toybuf, sizeof(toybuf))>0)
152       if ((pp = strrchr(toybuf, '/'))) xprintf("  Driver %s", pp+1);
153     xputc('\n');
154   }
155 
156   // If an address is assigned record that.
157 
158   ifre.ifr_addr.sa_family = AF_INET;
159   memset(&ifre.ifr_addr, 0, sizeof(ifre.ifr_addr));
160   ioctl(TT.sockfd, SIOCGIFADDR, &ifre);
161   pp = (char *)&ifre.ifr_addr;
162   for (i = 0; i<sizeof(ifre.ifr_addr); i++) if (pp[i]) break;
163 
164   if (!(toys.optflags&FLAG_S) && i != sizeof(ifre.ifr_addr)) {
165     struct sockaddr_in *si = (struct sockaddr_in *)&ifre.ifr_addr;
166     struct {
167       char *name;
168       int flag, ioctl;
169     } addr[] = {
170       {"addr", 0, 0},
171       {"P-t-P", IFF_POINTOPOINT, SIOCGIFDSTADDR},
172       {"Bcast", IFF_BROADCAST, SIOCGIFBRDADDR},
173       {"Mask", 0, SIOCGIFNETMASK}
174     };
175 
176     // TODO: can this be ipv6? Why are we checking here when ipv6 source later?
177     xprintf("%10c%s", ' ', (si->sin_family == AF_INET) ? "inet" :
178         (si->sin_family == AF_INET6) ? "inet6" : "unspec");
179 
180     for (i=0; i<ARRAY_LEN(addr); i++) {
181       if (!addr[i].flag || (flags & addr[i].flag)) {
182         if (addr[i].ioctl && ioctl(TT.sockfd, addr[i].ioctl, &ifre))
183           si->sin_family = 0;
184         xprintf(" %s:%s ", addr[i].name,
185           (si->sin_family == 0xFFFF || !si->sin_family)
186             ? "[NOT SET]" : inet_ntoa(si->sin_addr));
187       }
188     }
189 
190     xputc('\n');
191   }
192 
193   fp = fopen(pp = "/proc/net/if_inet6", "r");
194   if (fp) {
195     char iface_name[IFNAMSIZ];
196     int plen, iscope;
197 
198     while (fgets(toybuf, sizeof(toybuf), fp)) {
199       int nitems;
200       char ipv6_addr[40];
201 
202       nitems = sscanf(toybuf, "%32s %*08x %02x %02x %*02x %15s\n",
203                       ipv6_addr, &plen, &iscope, iface_name);
204       if (nitems<0 && feof(fp)) break;
205       if (nitems != 4) perror_exit("bad %s", pp);
206 
207       if (!strcmp(name, iface_name)) {
208         struct sockaddr_in6 s6;
209         char *ptr = ipv6_addr+sizeof(ipv6_addr)-1;
210 
211         // convert giant hex string into colon-spearated ipv6 address by
212         // inserting ':' every 4 characters.
213         for (i = 32; i; i--)
214           if ((*(ptr--) = ipv6_addr[i])) if (!(i&3)) *(ptr--) = ':';
215 
216         // Convert to binary and back to get abbreviated :: version
217         if (inet_pton(AF_INET6, ipv6_addr, (void *)&s6.sin6_addr) > 0) {
218           if (inet_ntop(AF_INET6, &s6.sin6_addr, toybuf, sizeof(toybuf))) {
219             char *scopes[] = {"Global","Host","Link","Site","Compat"},
220                  *scope = "Unknown";
221 
222             for (i=0; i<ARRAY_LEN(scopes); i++)
223               if (iscope == (!!i)<<(i+3)) scope = scopes[i];
224             if (toys.optflags&FLAG_S) xprintf(" %s/%d@%c", toybuf, plen,*scope);
225             else xprintf("%10cinet6 addr: %s/%d Scope: %s\n",
226                          ' ', toybuf, plen, scope);
227           }
228         }
229       }
230     }
231     fclose(fp);
232   }
233 
234   if (toys.optflags&FLAG_S) {
235     xputc('\n');
236     return;
237   }
238 
239   xprintf("%10c", ' ');
240 
241   if (flags) {
242     unsigned short mask = 1;
243     char **s, *str[] = {
244       "UP", "BROADCAST", "DEBUG", "LOOPBACK", "POINTOPOINT", "NOTRAILERS",
245       "RUNNING", "NOARP", "PROMISC", "ALLMULTI", "MASTER", "SLAVE", "MULTICAST",
246       "PORTSEL", "AUTOMEDIA", "DYNAMIC", NULL
247     };
248 
249     for (s = str; *s; s++) {
250       if (flags & mask) xprintf("%s ", *s);
251       mask = mask << 1;
252     }
253   } else xprintf("[NO FLAGS] ");
254 
255   if (ioctl(TT.sockfd, SIOCGIFMTU, &ifre) < 0) ifre.ifr_mtu = 0;
256   xprintf(" MTU:%d", ifre.ifr_mtu);
257   if (ioctl(TT.sockfd, SIOCGIFMETRIC, &ifre) < 0) ifre.ifr_metric = 0;
258   if (!ifre.ifr_metric) ifre.ifr_metric = 1;
259   xprintf("  Metric:%d", ifre.ifr_metric);
260 
261   // non-virtual interface
262 
263   if (val) {
264     char *label[] = {"RX bytes", "RX packets", "errors", "dropped", "overruns",
265       "frame", 0, 0, "TX bytes", "TX packets", "errors", "dropped", "overruns",
266       "collisions", "carrier", 0, "txqueuelen"};
267     signed char order[] = {-1, 1, 2, 3, 4, 5, -1, 9, 10, 11, 12, 14, -1,
268       13, 16, -1, 0, 8};
269     int i;
270 
271     // Query txqueuelen
272     if (ioctl(TT.sockfd, SIOCGIFTXQLEN, &ifre) >= 0) val[16] = ifre.ifr_qlen;
273     else val[16] = -1;
274 
275     for (i = 0; i<sizeof(order); i++) {
276       int j = order[i];
277 
278       if (j < 0) xprintf("\n%10c", ' ');
279       else xprintf("%s:%llu ", label[j], val[j]);
280     }
281   }
282   xputc('\n');
283 
284   if(!ioctl(TT.sockfd, SIOCGIFMAP, &ifre) && (ifre.ifr_map.irq ||
285       ifre.ifr_map.mem_start || ifre.ifr_map.dma || ifre.ifr_map.base_addr))
286   {
287     xprintf("%10c", ' ');
288     if(ifre.ifr_map.irq) xprintf("Interrupt:%d ", ifre.ifr_map.irq);
289     if(ifre.ifr_map.base_addr >= 0x100) // IO_MAP_INDEX
290       xprintf("Base address:0x%x ", ifre.ifr_map.base_addr);
291     if(ifre.ifr_map.mem_start)
292       xprintf("Memory:%lx-%lx ", ifre.ifr_map.mem_start, ifre.ifr_map.mem_end);
293     if(ifre.ifr_map.dma) xprintf("DMA chan:%x ", ifre.ifr_map.dma);
294     xputc('\n');
295   }
296   xputc('\n');
297 }
298 
show_iface(char * iface_name)299 static void show_iface(char *iface_name)
300 {
301   char *name;
302   struct string_list *ifaces = 0, *sl;
303   int i, j;
304   FILE *fp;
305 
306   fp = xfopen("/proc/net/dev", "r");
307 
308   for (i=0; fgets(toybuf, sizeof(toybuf), fp); i++) {
309     char *buf = toybuf;
310     unsigned long long val[17];
311 
312     if (i<2) continue;
313 
314     while (isspace(*buf)) buf++;
315     name = strsep(&buf, ":");
316     if(!buf) error_exit("bad name %s", name);
317 
318     errno = 0;
319     for (j=0; j<16 && !errno; j++) val[j] = strtoll(buf, &buf, 0);
320     if (errno) perror_exit("bad %s at %s", name, buf);
321 
322     if (iface_name) {
323       if (!strcmp(iface_name, name)) {
324         display_ifconfig(iface_name, 1, val);
325 
326         return;
327       }
328     } else {
329       sl = xmalloc(sizeof(*sl)+strlen(name)+1);
330       strcpy(sl->str, name);
331       sl->next = ifaces;
332       ifaces = sl;
333 
334       display_ifconfig(sl->str, toys.optflags & FLAG_a, val);
335     }
336   }
337   fclose(fp);
338 
339   if (iface_name) display_ifconfig(iface_name, 1, 0);
340   else {
341     struct ifconf ifcon;
342     struct ifreq *ifre;
343     int num;
344 
345     // Loop until buffer's big enough
346     ifcon.ifc_buf = NULL;
347     for (num = 30;;num += 10) {
348       ifcon.ifc_len = sizeof(struct ifreq)*num;
349       ifcon.ifc_buf = xrealloc(ifcon.ifc_buf, ifcon.ifc_len);
350       xioctl(TT.sockfd, SIOCGIFCONF, &ifcon);
351       if (ifcon.ifc_len != sizeof(struct ifreq)*num) break;
352     }
353 
354     ifre = ifcon.ifc_req;
355     for(num = 0; num < ifcon.ifc_len && ifre; num += sizeof(struct ifreq), ifre++)
356     {
357       // Skip duplicates
358       for(sl = ifaces; sl; sl = sl->next)
359         if(!strcmp(sl->str, ifre->ifr_name)) break;
360 
361       if(!sl) display_ifconfig(ifre->ifr_name, toys.optflags & FLAG_a, 0);
362     }
363 
364     free(ifcon.ifc_buf);
365   }
366 
367   llist_traverse(ifaces, free);
368 }
369 
370 // Encode offset and size of field into an int, and make result negative
371 #define IFREQ_OFFSZ(x) -(int)((offsetof(struct ifreq, x)<<16) + sizeof(ifre.x))
372 
ifconfig_main(void)373 void ifconfig_main(void)
374 {
375   char **argv = toys.optargs;
376   struct ifreq ifre;
377   int i;
378 
379   TT.sockfd = xsocket(AF_INET, SOCK_DGRAM, 0);
380   if(toys.optc < 2) {
381     show_iface(*argv);
382     return;
383   }
384 
385   // Open interface
386   memset(&ifre, 0, sizeof(struct ifreq));
387   xstrncpy(ifre.ifr_name, *argv, IFNAMSIZ);
388 
389   // Perform operations on interface
390   while(*++argv) {
391     // Table of known operations
392     struct argh {
393       char *name;
394       int on, off; // set, clear
395     } try[] = {
396       {0, IFF_UP|IFF_RUNNING, SIOCSIFADDR},
397       {"up", IFF_UP|IFF_RUNNING, 0},
398       {"down", 0, IFF_UP},
399       {"arp", 0, IFF_NOARP},
400       {"promisc", IFF_PROMISC, 0},
401       {"allmulti", IFF_ALLMULTI, 0},
402       {"multicast", IFF_MULTICAST, 0},
403       {"pointopoint", IFF_POINTOPOINT, SIOCSIFDSTADDR},
404       {"broadcast", IFF_BROADCAST, SIOCSIFBRDADDR},
405       {"netmask", 0, SIOCSIFNETMASK},
406       {"dstaddr", 0, SIOCSIFDSTADDR},
407       {"mtu", IFREQ_OFFSZ(ifr_mtu), SIOCSIFMTU},
408       {"keepalive", IFREQ_OFFSZ(ifr_data), SIOCDEVPRIVATE}, // SIOCSKEEPALIVE
409       {"outfill", IFREQ_OFFSZ(ifr_data), SIOCDEVPRIVATE+2}, // SIOCSOUTFILL
410       {"metric", IFREQ_OFFSZ(ifr_metric), SIOCSIFMETRIC},
411       {"txqueuelen", IFREQ_OFFSZ(ifr_qlen), SIOCSIFTXQLEN},
412       {"mem_start", IFREQ_OFFSZ(ifr_map.mem_start), SIOCSIFMAP},
413       {"io_addr", IFREQ_OFFSZ(ifr_map.base_addr), SIOCSIFMAP},
414       {"irq", IFREQ_OFFSZ(ifr_map.irq), SIOCSIFMAP},
415       {"inet", 0, 0},
416       {"inet6", 0, 0}
417     };
418     char *s = *argv;
419     int rev = (*s == '-');
420 
421     s += rev;
422 
423     // "set hardware address" is oddball enough to special case
424     if (!strcmp(*argv, "hw")) {
425       char *hw_addr, *ptr, *p;
426       struct sockaddr *sock = &ifre.ifr_hwaddr;
427       int count = 6;
428 
429       ptr = p = (char *)sock->sa_data;
430       memset(sock, 0, sizeof(struct sockaddr));
431       if (argv[1]) {
432         if (!strcmp("ether", *++argv)) sock->sa_family = ARPHRD_ETHER;
433         else if (!strcmp("infiniband", *argv)) {
434           sock->sa_family = ARPHRD_INFINIBAND;
435           count = 20;
436           p = ptr = toybuf;
437         }
438       }
439       if (!sock->sa_family || !argv[1]) help_exit("bad hw '%s'", *argv);
440       hw_addr = *++argv;
441 
442       // Parse and verify address.
443       while (*hw_addr && (p-ptr) < count) {
444         int val, len = 0;
445 
446         if (*hw_addr == ':') hw_addr++;
447         sscanf(hw_addr, "%2x%n", &val, &len);
448         if (!len || len > 2) break; // 1 nibble can be set e.g. C2:79:38:95:D:A
449         hw_addr += len;
450         *p++ = val;
451       }
452 
453       if ((p-ptr) != count || *hw_addr)
454         error_exit("bad hw-addr '%s'", *argv);
455 
456       // the linux kernel's "struct sockaddr" (include/linux/socket.h in the
457       // kernel source) only has 14 bytes of sa_data, and an infiniband address
458       // is 20. So if we go through the ioctl, the kernel will truncate
459       // infiniband addresses, meaning we have to go through sysfs instead.
460       if (sock->sa_family == ARPHRD_INFINIBAND && !strchr(ifre.ifr_name, '/')) {
461         int fd;
462 
463         sprintf(toybuf, "/sys/class/net/%s/address", ifre.ifr_name);
464         fd = xopen(toybuf, O_RDWR);
465         xwrite(fd, *argv, strlen(*argv));
466         close(fd);
467       } else xioctl(TT.sockfd, SIOCSIFHWADDR, &ifre);
468       continue;
469 
470     // Add/remove ipv6 address to interface
471 
472     } else if (!strcmp(*argv, "add") || !strcmp(*argv, "del")) {
473       struct ifreq_inet6 {
474         struct in6_addr addr;
475         unsigned prefix;
476         int index;
477       } ifre6;
478       int plen, fd6 = xsocket(AF_INET6, SOCK_DGRAM, 0);
479 
480       if (!argv[1]) help_exit("%s", *argv);
481 
482       plen = get_addrinfo(argv[1], AF_INET6, &ifre6.addr);
483       if (plen < 0) plen = 128;
484       xioctl(fd6, SIOCGIFINDEX, &ifre);
485       ifre6.index = ifre.ifr_ifindex;
486       ifre6.prefix = plen;
487       xioctl(fd6, **(argv++)=='a' ? SIOCSIFADDR : SIOCDIFADDR, &ifre6);
488 
489       close(fd6);
490       continue;
491     // Iterate through table to find/perform operation
492     } else for (i = 0; i<ARRAY_LEN(try); i++) {
493       struct argh *t = try+i;
494       int on = t->on, off = t->off;
495 
496       if (!t->name) {
497         if (isdigit(**argv) || !strcmp(*argv, "default")) argv--;
498         else continue;
499       } else if (strcmp(t->name, s)) continue;
500 
501       // Is this an SIOCSI entry?
502       if ((off|0xff) == 0x89ff) {
503         if (!rev) {
504           if (!*++argv) error_exit("%s needs argument", t->name);
505 
506           // Assign value to ifre field and call ioctl? (via IFREQ_OFFSZ.)
507           if (on < 0) {
508             long l = strtoul(*argv, 0, 0);
509 
510             if (off == SIOCSIFMAP) xioctl(TT.sockfd, SIOCGIFMAP, &ifre);
511             on = -on;
512             poke((on>>16) + (char *)&ifre, l, on&15);
513             xioctl(TT.sockfd, off, &ifre);
514             break;
515           } else {
516             struct sockaddr_in *si = (struct sockaddr_in *)&ifre.ifr_addr;
517             int mask = -1;
518 
519             si->sin_family = AF_INET;
520 
521             if (!strcmp(*argv, "default")) si->sin_addr.s_addr = INADDR_ANY;
522             else mask = get_addrinfo(*argv, AF_INET, &si->sin_addr);
523             xioctl(TT.sockfd, off, &ifre);
524 
525             // Handle /netmask
526             if (mask >= 0) {
527               // sin_addr probably isn't unaligned, but just in case...
528               mask = htonl((~0)<<(32-mask));
529               memcpy(&si->sin_addr, &mask, 4);
530               xioctl(TT.sockfd, SIOCSIFNETMASK, &ifre);
531             }
532           }
533         }
534         off = 0;
535       }
536 
537       // Set flags
538       if (on || off) {
539         xioctl(TT.sockfd, SIOCGIFFLAGS, &ifre);
540         ifre.ifr_flags &= ~(rev ? on : off);
541         ifre.ifr_flags |= (rev ? off : on);
542         xioctl(TT.sockfd, SIOCSIFFLAGS, &ifre);
543       }
544 
545       break;
546     }
547     if (i == ARRAY_LEN(try)) help_exit("bad argument '%s'", *argv);
548   }
549   close(TT.sockfd);
550 }
551