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34#define FOR_arp
35#include "toys.h"
36#include <net/if_arp.h>
37
38GLOBALS(
39 char *hw_type;
40 char *af_type_A;
41 char *af_type_p;
42 char *interface;
43
44 int sockfd;
45 char *device;
46)
47
48struct arpreq req;
49
50struct type {
51 char *name;
52 int val;
53};
54
55struct type hwtype[] = {
56 {"ether", ARPHRD_ETHER },
57 {"loop" ,ARPHRD_LOOPBACK},
58 {"ppp" ,ARPHRD_PPP},
59 {"infiniband" ,ARPHRD_INFINIBAND},
60 {NULL, -1},
61};
62
63struct type aftype[] = {
64 {"inet", AF_INET },
65 {"inet6" ,AF_INET6},
66 {"unspec" ,AF_UNSPEC},
67 {NULL, -1},
68};
69
70struct type flag_type[] = {
71 {"PERM", ATF_PERM },
72 {"PUB" ,ATF_PUBL},
73 {"DONTPUB" ,ATF_DONTPUB},
74 {"TRAIL" ,ATF_USETRAILERS},
75 {NULL, -1},
76};
77
78static int get_index(struct type arr[], char *name)
79{
80 int i;
81
82 for (i = 0; arr[i].name; i++)
83 if (!strcmp(arr[i].name, name)) break;
84 return arr[i].val;
85}
86
87static void resolve_host(char *host, struct sockaddr *sa)
88{
89 struct addrinfo *ai = xgetaddrinfo(host, NULL, AF_INET, SOCK_STREAM, 0, 0);
90
91 memcpy(sa, ai->ai_addr, ai->ai_addrlen);
92 freeaddrinfo(ai);
93}
94
95static void check_flags(int *i, char** argv)
96{
97 struct sockaddr sa;
98 int flag = *i, j;
99 struct flags {
100 char *name;
101 int or, flag;
102 } f[] = {
103 {"pub", 1 ,ATF_PUBL},
104 {"priv", 0 ,~ATF_PUBL},
105 {"trail", 1, ATF_USETRAILERS},
106 {"temp", 0, ~ATF_PERM},
107 {"dontpub",1, ATF_DONTPUB},
108 };
109
110 for (;*argv; argv++) {
111 for (j = 0; j < ARRAY_LEN(f); j++) {
112 if (!strcmp(*argv, f[j].name)) {
113 (f[j].or) ?(flag |= f[j].flag):(flag &= f[j].flag);
114 break;
115 }
116 }
117 if (j > 4 && !strcmp(*argv, "netmask")) {
118 if (!*++argv) error_exit("NULL netmask");
119 if (strcmp(*argv, "255.255.255.255")) {
120 resolve_host(toys.optargs[0], &sa);
121 memcpy(&req.arp_netmask, &sa, sizeof(sa));
122 flag |= ATF_NETMASK;
123 } else argv++;
124 } else if (j > 4 && !strcmp(*argv, "dev")) {
125 if (!*++argv) error_exit("NULL dev");
126 TT.device = *argv;
127 } else if (j > 4) error_exit("invalid arg");
128 }
129 *i = flag;
130}
131
132static int set_entry(void)
133{
134 int flags = 0;
135
136 if (!toys.optargs[1]) error_exit("bad syntax");
137
138 if (!FLAG(D)) {
139 char *ptr = toys.optargs[1];
140 char *p = ptr, *hw_addr = req.arp_ha.sa_data;
141
142 while (*hw_addr && (p-ptr) < 6) {
143 int val, len;
144
145 if (*hw_addr == ':') hw_addr++;
146 if (!sscanf(hw_addr, "%2x%n", &val, &len)) break;
147 hw_addr += len;
148 *p++ = val;
149 }
150
151 if ((p-ptr) != 6 || *hw_addr)
152 error_exit("bad hw addr '%s'", req.arp_ha.sa_data);
153 } else {
154 struct ifreq ifre;
155
156 xstrncpy(ifre.ifr_name, toys.optargs[1], IFNAMSIZ);
157 xioctl(TT.sockfd, SIOCGIFHWADDR, &ifre);
158 if (FLAG(H) && ifre.ifr_hwaddr.sa_family != ARPHRD_ETHER)
159 error_exit("protocol type mismatch");
160 memcpy(&req.arp_ha, &(ifre.ifr_hwaddr), sizeof(req.arp_ha));
161 }
162
163 flags = ATF_PERM | ATF_COM;
164 if (toys.optargs[2]) check_flags(&flags, (toys.optargs+2));
165 req.arp_flags = flags;
166 xstrncpy(req.arp_dev, TT.device, sizeof(req.arp_dev));
167 xioctl(TT.sockfd, SIOCSARP, &req);
168
169 if (FLAG(v)) xprintf("Entry set for %s\n", toys.optargs[0]);
170 return 0;
171}
172
173static int ip_to_host(struct sockaddr *sa, int flag)
174{
175 int status = 0;
176 char hbuf[NI_MAXHOST] = {0,}, sbuf[NI_MAXSERV] = {0,};
177 socklen_t len = sizeof(struct sockaddr_in6);
178
179 *toybuf = 0;
180 if (!(status = getnameinfo(sa, len, hbuf, sizeof(hbuf), sbuf,
181 sizeof(sbuf), flag))) {
182 strcpy(toybuf, hbuf);
183 return 0;
184 }
185 return 1;
186}
187
188static int delete_entry(void)
189{
190 int flags = ATF_PERM;
191
192 if (toys.optargs[1]) check_flags(&flags, (toys.optargs+1));
193 req.arp_flags = flags;
194 xstrncpy(req.arp_dev, TT.device, sizeof(req.arp_dev));
195 xioctl(TT.sockfd, SIOCDARP, &req);
196
197 if (FLAG(v)) xprintf("Delete entry for %s\n", toys.optargs[0]);
198 return 0;
199}
200
201void arp_main(void)
202{
203 struct sockaddr sa;
204 char ip[16], hw_addr[30], mask[16], dev[16], *host_ip = NULL;
205 FILE *fp;
206 int h_type, type, flag, i, entries = 0, disp = 0;
207
208 TT.device = "";
209 memset(&sa, 0, sizeof(sa));
210 TT.sockfd = xsocket(AF_INET, SOCK_STREAM, 0);
211
212 if (FLAG(A) || FLAG(p)) {
213 if ((type = get_index(aftype,
214 (TT.af_type_A)?TT.af_type_A:TT.af_type_p)) != AF_INET)
215 error_exit((type != -1)?"only inet supported by kernel":"unknown family");
216 }
217
218 req.arp_ha.sa_family = ARPHRD_ETHER;
219 if (FLAG(H)) {
220 if ((type = get_index(hwtype, TT.hw_type)) != ARPHRD_ETHER)
221 error_exit((type != -1)?"h/w type not supported":"unknown h/w type");
222 req.arp_ha.sa_family = type;
223 }
224
225 if (FLAG(s) || FLAG(d)) {
226 if (!toys.optargs[0]) error_exit("-%c needs a host name", FLAG(d)?'d':'s');
227 resolve_host(toys.optargs[0], &sa);
228 memcpy(&req.arp_pa, &sa, sizeof(struct sockaddr));
229
230 if (FLAG(s) && !set_entry()) return;
231 if (FLAG(d) && !delete_entry()) return;
232 }
233
234
235
236 if (toys.optargs[0]) {
237 resolve_host(toys.optargs[0], &sa);
238 ip_to_host(&sa, NI_NUMERICHOST);
239 host_ip = xstrdup(toybuf);
240 }
241
242 fp = xfopen("/proc/net/arp", "r");
243 fgets(toybuf, sizeof(toybuf), fp);
244 while (fscanf(fp, "%15s 0x%x 0x%x %29s %15s %15s",
245 ip, &h_type, &flag, hw_addr, mask, dev) == 6) {
246 char *host_name = "?";
247
248 entries++;
249 if ((FLAG(H) && get_index(hwtype, TT.hw_type) != h_type) ||
250 (FLAG(i) && strcmp(TT.interface, dev)) ||
251 (toys.optargs[0] && strcmp(host_ip, ip))) {
252 continue;
253 }
254
255 resolve_host(ip, &sa);
256 if (FLAG(n)) ip_to_host(&sa, NI_NUMERICHOST);
257 else if (!ip_to_host(&sa, NI_NAMEREQD)) host_name = toybuf;
258
259 disp++;
260 printf("%s (%s) at" , host_name, ip);
261
262 for (i = 0; hwtype[i].name; i++)
263 if (hwtype[i].val & h_type) break;
264 if (!hwtype[i].name) error_exit("unknown h/w type");
265
266 if (!(flag & ATF_COM)) {
267 if ((flag & ATF_PUBL)) printf(" *");
268 else printf(" <incomplete>");
269 } else printf(" %s [%s]", hw_addr, hwtype[i].name);
270
271 if (flag & ATF_NETMASK) printf("netmask %s ", mask);
272
273 for (i = 0; flag_type[i].name; i++)
274 if (flag_type[i].val & flag) printf(" %s", flag_type[i].name);
275
276 printf(" on %s\n", dev);
277 }
278
279 if (FLAG(v))
280 xprintf("Entries: %d\tSkipped: %d\tFound: %d\n",
281 entries, entries - disp, disp);
282 if (toys.optargs[0] && !disp)
283 xprintf("%s (%s) -- no entry\n", toys.optargs[0], host_ip);
284
285 if (CFG_TOYBOX_FREE) {
286 free(host_ip);
287 fclose(fp);
288 }
289}
290
