1 /* netstat.c - Display Linux networking subsystem. 2 * 3 * Copyright 2012 Ranjan Kumar <ranjankumar.bth (at) gmail.com> 4 * Copyright 2013 Kyungwan Han <asura321 (at) gmail.com> 5 * 6 * Not in SUSv4. 7 * 8 USE_NETSTAT(NEWTOY(netstat, "pWrxwutneal", TOYFLAG_BIN)) 9 config NETSTAT 10 bool "netstat" 11 default y 12 help 13 usage: netstat [-pWrxwutneal] 14 15 Display networking information. Default is netsat -tuwx 16 17 -r routing table 18 -a all sockets (not just connected) 19 -l listening server sockets 20 -t TCP sockets 21 -u UDP sockets 22 -w raw sockets 23 -x unix sockets 24 -e extended info 25 -n don't resolve names 26 -W wide display 27 -p PID/Program name of sockets 28 */ 29 30 #define FOR_netstat 31 #include "toys.h" 32 #include <net/route.h> 33 34 GLOBALS( 35 struct num_cache *inodes; 36 int wpad; 37 ); 38 39 // convert address into text format. 40 static void addr2str(int af, void *addr, unsigned port, char *buf, int len, 41 char *proto) 42 { 43 int pos, count; 44 struct servent *ser = 0; 45 46 // Convert to numeric address 47 if (!inet_ntop(af, addr, buf, 256)) { 48 *buf = 0; 49 50 return; 51 } 52 buf[len] = 0; 53 pos = strlen(buf); 54 55 // If there's no port number, it's a local :* binding, nothing to look up. 56 if (!port) { 57 if (len-pos<2) pos = len-2; 58 strcpy(buf+pos, ":*"); 59 60 return; 61 } 62 63 if (!(toys.optflags & FLAG_n)) { 64 struct addrinfo hints, *result, *rp; 65 char cut[4]; 66 67 memset(&hints, 0, sizeof(struct addrinfo)); 68 hints.ai_family = af; 69 70 if (!getaddrinfo(buf, NULL, &hints, &result)) { 71 socklen_t sock_len = (af == AF_INET) ? sizeof(struct sockaddr_in) 72 : sizeof(struct sockaddr_in6); 73 74 // We assume that a failing getnameinfo dosn't stomp "buf" here. 75 for (rp = result; rp; rp = rp->ai_next) 76 if (!getnameinfo(rp->ai_addr, sock_len, buf, 256, 0, 0, 0)) break; 77 freeaddrinfo(result); 78 buf[len] = 0; 79 pos = strlen(buf); 80 } 81 82 // Doesn't understand proto "tcp6", so truncate 83 memcpy(cut, proto, 3); 84 cut[3] = 0; 85 ser = getservbyport(htons(port), cut); 86 } 87 88 // Append :service 89 count = snprintf(0, 0, ":%u", port); 90 if (ser) { 91 count = snprintf(0, 0, ":%s", ser->s_name); 92 // sheer paranoia 93 if (count>=len) { 94 count = len-1; 95 ser->s_name[count] = 0; 96 } 97 } 98 if (len-pos<count) pos = len-count; 99 if (ser) sprintf(buf+pos, ":%s", ser->s_name); 100 else sprintf(buf+pos, ":%u", port); 101 } 102 103 // Display info for tcp/udp/raw 104 static void show_ip(char *fname) 105 { 106 char *ss_state = "UNKNOWN", buf[12], *s, *label = strrchr(fname, '/')+1; 107 char *state_label[] = {"", "ESTABLISHED", "SYN_SENT", "SYN_RECV", "FIN_WAIT1", 108 "FIN_WAIT2", "TIME_WAIT", "CLOSE", "CLOSE_WAIT", 109 "LAST_ACK", "LISTEN", "CLOSING", "UNKNOWN"}; 110 struct passwd *pw; 111 FILE *fp = fopen(fname, "r"); 112 113 if (!fp) { 114 perror_msg("'%s'", fname); 115 return; 116 } 117 118 if(!fgets(toybuf, sizeof(toybuf), fp)) return; //skip header. 119 120 while (fgets(toybuf, sizeof(toybuf), fp)) { 121 char lip[256], rip[256]; 122 union { 123 struct {unsigned u; unsigned char b[4];} i4; 124 struct {struct {unsigned a, b, c, d;} u; unsigned char b[16];} i6; 125 } laddr, raddr; 126 unsigned lport, rport, state, txq, rxq, num, uid, nitems; 127 unsigned long inode; 128 129 // Try ipv6, then try ipv4 130 nitems = sscanf(toybuf, 131 " %d: %8x%8x%8x%8x:%x %8x%8x%8x%8x:%x %x %x:%x %*X:%*X %*X %d %*d %ld", 132 &num, &laddr.i6.u.a, &laddr.i6.u.b, &laddr.i6.u.c, 133 &laddr.i6.u.d, &lport, &raddr.i6.u.a, &raddr.i6.u.b, 134 &raddr.i6.u.c, &raddr.i6.u.d, &rport, &state, &txq, &rxq, 135 &uid, &inode); 136 137 if (nitems!=16) { 138 nitems = sscanf(toybuf, 139 " %d: %x:%x %x:%x %x %x:%x %*X:%*X %*X %d %*d %ld", 140 &num, &laddr.i4.u, &lport, &raddr.i4.u, &rport, &state, &txq, 141 &rxq, &uid, &inode); 142 143 if (nitems!=10) continue; 144 nitems = AF_INET; 145 } else nitems = AF_INET6; 146 147 // Should we display this? (listening or all or TCP/UDP/RAW) 148 if (!((toys.optflags & FLAG_l) && (!rport && (state & 0xA))) 149 && !(toys.optflags & FLAG_a) && !(rport & (0x10 | 0x20 | 0x40))) 150 continue; 151 152 addr2str(nitems, &laddr, lport, lip, TT.wpad, label); 153 addr2str(nitems, &raddr, rport, rip, TT.wpad, label); 154 155 // Display data 156 s = label; 157 if (strstart(&s, "tcp")) { 158 int sz = ARRAY_LEN(state_label); 159 if (!state || state >= sz) state = sz-1; 160 ss_state = state_label[state]; 161 } else if (strstart(&s, "udp")) { 162 if (state == 1) ss_state = state_label[state]; 163 else if (state == 7) ss_state = ""; 164 } else if (strstart(&s, "raw")) sprintf(ss_state = buf, "%u", state); 165 166 if (!(toys.optflags & FLAG_n) && (pw = bufgetpwuid(uid))) 167 snprintf(toybuf, sizeof(toybuf), "%s", pw->pw_name); 168 else snprintf(toybuf, sizeof(toybuf), "%d", uid); 169 170 printf("%-6s%6d%7d ", label, rxq, txq); 171 printf("%*.*s %*.*s ", -TT.wpad, TT.wpad, lip, -TT.wpad, TT.wpad, rip); 172 printf("%-11s", ss_state); 173 if ((toys.optflags & FLAG_e)) printf(" %-10s %-11ld", toybuf, inode); 174 if ((toys.optflags & FLAG_p)) { 175 struct num_cache *nc = get_num_cache(TT.inodes, inode); 176 177 printf(" %s", nc ? nc->data : "-"); 178 } 179 xputc('\n'); 180 } 181 fclose(fp); 182 } 183 184 static void show_unix_sockets(void) 185 { 186 char *types[] = {"","STREAM","DGRAM","RAW","RDM","SEQPACKET","DCCP","PACKET"}, 187 *states[] = {"","LISTENING","CONNECTING","CONNECTED","DISCONNECTING"}, 188 *s, *ss; 189 unsigned long refcount, flags, type, state, inode; 190 FILE *fp = xfopen("/proc/net/unix", "r"); 191 192 if(!fgets(toybuf, sizeof(toybuf), fp)) return; //skip header. 193 194 while (fgets(toybuf, sizeof(toybuf), fp)) { 195 unsigned offset = 0; 196 197 // count = 6 or 7 (first field ignored, sockets don't always have filenames) 198 if (6<sscanf(toybuf, "%*p: %lX %*X %lX %lX %lX %lu %n", 199 &refcount, &flags, &type, &state, &inode, &offset)) 200 continue; 201 202 // Linux exports only SO_ACCEPTCON since 2.3.15pre3 in 1999, but let's 203 // filter in case they add more someday. 204 flags &= 1<<16; 205 206 // Only show unconnected listening sockets with -a 207 if (state==1 && flags && !(toys.optflags&FLAG_a)) continue; 208 209 if (type==10) type = 7; // move SOCK_PACKET into line 210 if (type>ARRAY_LEN(types)) type = 0; 211 if (state>ARRAY_LEN(states) || (state==1 && !flags)) state = 0; 212 sprintf(toybuf, "[ %s]", flags ? "ACC " : ""); 213 214 printf("unix %-6ld %-11s %-10s %-13s %8lu ", 215 refcount, toybuf, types[type], states[state], inode); 216 if (toys.optflags & FLAG_p) { 217 struct num_cache *nc = get_num_cache(TT.inodes, inode); 218 219 printf("%-19.19s", nc ? nc->data : "-"); 220 } 221 222 if (offset) { 223 if ((ss = strrchr(s = toybuf+offset, '\n'))) *ss = 0; 224 printf("%s", s); 225 } 226 xputc('\n'); 227 } 228 229 fclose(fp); 230 } 231 232 static int scan_pids(struct dirtree *node) 233 { 234 char *s = toybuf+256; 235 struct dirent *entry; 236 DIR *dp; 237 int pid, dirfd; 238 239 if (!node->parent) return DIRTREE_RECURSE; 240 if (!(pid = atol(node->name))) return 0; 241 242 sprintf(toybuf, "/proc/%d/cmdline", pid); 243 if (!(readfile(toybuf, toybuf, 256))) return 0; 244 245 sprintf(s, "%d/fd", pid); 246 if (-1==(dirfd = openat(dirtree_parentfd(node), s, O_RDONLY))) return 0; 247 if (!(dp = fdopendir(dirfd))) { 248 close(dirfd); 249 250 return 0; 251 } 252 253 while ((entry = readdir(dp))) { 254 s = toybuf+256; 255 if (!readlinkat0(dirfd, entry->d_name, s, sizeof(toybuf)-256)) continue; 256 // Can the "[0000]:" happen in a modern kernel? 257 if (strstart(&s, "socket:[") || strstart(&s, "[0000]:")) { 258 long long ll = atoll(s); 259 260 sprintf(s, "%d/%s", pid, getbasename(toybuf)); 261 add_num_cache(&TT.inodes, ll, s, strlen(s)+1); 262 } 263 } 264 closedir(dp); 265 266 return 0; 267 } 268 269 /* 270 * extract inet4 route info from /proc/net/route file and display it. 271 */ 272 static void display_routes(void) 273 { 274 static const char flagchars[] = "GHRDMDAC"; 275 static const unsigned flagarray[] = { 276 RTF_GATEWAY, RTF_HOST, RTF_REINSTATE, RTF_DYNAMIC, RTF_MODIFIED 277 }; 278 unsigned long dest, gate, mask; 279 int flags, ref, use, metric, mss, win, irtt; 280 char *out = toybuf, *flag_val; 281 char iface[64]={0}; 282 FILE *fp = xfopen("/proc/net/route", "r"); 283 284 if(!fgets(toybuf, sizeof(toybuf), fp)) return; //skip header. 285 286 printf("Kernel IP routing table\n" 287 "Destination\tGateway \tGenmask \tFlags %s Iface\n", 288 !(toys.optflags&FLAG_e) ? " MSS Window irtt" : "Metric Ref Use"); 289 290 while (fgets(toybuf, sizeof(toybuf), fp)) { 291 char *destip = 0, *gateip = 0, *maskip = 0; 292 293 if (11 != sscanf(toybuf, "%63s%lx%lx%X%d%d%d%lx%d%d%d", iface, &dest, 294 &gate, &flags, &ref, &use, &metric, &mask, &mss, &win, &irtt)) 295 break; 296 297 // skip down interfaces. 298 if (!(flags & RTF_UP)) continue; 299 300 // TODO /proc/net/ipv6_route 301 302 if (dest) { 303 if (inet_ntop(AF_INET, &dest, out, 16)) destip = out; 304 } else destip = (toys.optflags&FLAG_n) ? "0.0.0.0" : "default"; 305 out += 16; 306 307 if (gate) { 308 if (inet_ntop(AF_INET, &gate, out, 16)) gateip = out; 309 } else gateip = (toys.optflags&FLAG_n) ? "0.0.0.0" : "*"; 310 out += 16; 311 312 // TODO /24 313 //For Mask 314 if (inet_ntop(AF_INET, &mask, out, 16)) maskip = out; 315 else maskip = "?"; 316 out += 16; 317 318 //Get flag Values 319 flag_val = out; 320 *out++ = 'U'; 321 for (dest = 0; dest < ARRAY_LEN(flagarray); dest++) 322 if (flags&flagarray[dest]) *out++ = flagchars[dest]; 323 *out = 0; 324 if (flags & RTF_REJECT) *flag_val = '!'; 325 326 printf("%-15.15s %-15.15s %-16s%-6s", destip, gateip, maskip, flag_val); 327 if (!(toys.optflags & FLAG_e)) 328 printf("%5d %-5d %6d %s\n", mss, win, irtt, iface); 329 else printf("%-6d %-2d %7d %s\n", metric, ref, use, iface); 330 } 331 332 fclose(fp); 333 } 334 335 void netstat_main(void) 336 { 337 int tuwx = FLAG_t|FLAG_u|FLAG_w|FLAG_x; 338 char *type = "w/o"; 339 340 TT.wpad = (toys.optflags&FLAG_W) ? 51 : 23; 341 if (!(toys.optflags&(FLAG_r|tuwx))) toys.optflags |= tuwx; 342 if (toys.optflags & FLAG_r) display_routes(); 343 if (!(toys.optflags&tuwx)) return; 344 345 if (toys.optflags & FLAG_a) type = "established and"; 346 else if (toys.optflags & FLAG_l) type = "only"; 347 348 if (toys.optflags & FLAG_p) dirtree_read("/proc", scan_pids); 349 350 if (toys.optflags&(FLAG_t|FLAG_u|FLAG_w)) { 351 printf("Active %s (%s servers)\n", "Internet connections", type); 352 printf("Proto Recv-Q Send-Q %*s %*s State ", -TT.wpad, "Local Address", 353 -TT.wpad, "Foreign Address"); 354 if (toys.optflags & FLAG_e) printf(" User Inode "); 355 if (toys.optflags & FLAG_p) printf(" PID/Program Name"); 356 xputc('\n'); 357 358 if (toys.optflags & FLAG_t) { 359 show_ip("/proc/net/tcp"); 360 show_ip("/proc/net/tcp6"); 361 } 362 if (toys.optflags & FLAG_u) { 363 show_ip("/proc/net/udp"); 364 show_ip("/proc/net/udp6"); 365 } 366 if (toys.optflags & FLAG_w) { 367 show_ip("/proc/net/raw"); 368 show_ip("/proc/net/raw6"); 369 } 370 } 371 372 if (toys.optflags & FLAG_x) { 373 printf("Active %s (%s servers)\n", "UNIX domain sockets", type); 374 375 printf("Proto RefCnt Flags\t Type\t State\t %s Path\n", 376 (toys.optflags&FLAG_p) ? "PID/Program Name" : "I-Node"); 377 show_unix_sockets(); 378 } 379 380 if ((toys.optflags & FLAG_p) && CFG_TOYBOX_FREE) 381 llist_traverse(TT.inodes, free); 382 toys.exitval = 0; 383 } 384
