procps/fuser.c

   1 /*
   2  * tiny fuser implementation
   3  *
   4  * Copyright 2004 Tony J. White
   5  *
   6  * May be distributed under the conditions of the
   7  * GNU Library General Public License
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13 #include <string.h>
  14 #include <limits.h>
  15 #include <dirent.h>
  16 #include <signal.h>
  17 #include <sys/types.h>
  18 #include <sys/ioctl.h>
  19 #include <sys/stat.h>
  20 #include <sys/socket.h>
  21 #include <sys/sysmacros.h>
  22 #include "busybox.h"
  23
  24 #define FUSER_PROC_DIR "/proc"
  25 #define FUSER_MAX_LINE 255
  26
  27 #define FUSER_OPT_MOUNT  1
  28 #define FUSER_OPT_KILL   2
  29 #define FUSER_OPT_SILENT 4
  30 #define FUSER_OPT_IP6    8
  31 #define FUSER_OPT_IP4    16
  32
  33 typedef struct inode_list {
  34         ino_t inode;
  35         dev_t dev;
  36         struct inode_list *next;
  37 } inode_list;
  38
  39 typedef struct pid_list {
  40         pid_t pid;
  41         struct pid_list *next;
  42 } pid_list;
  43
  44 static int fuser_option(char *option)
  45 {
  46         int opt = 0;
  47
  48         if(!(strlen(option))) return 0;
  49         if(option[0] != '-') return 0;
  50         ++option;
  51         while(*option != '\0') {
  52                 if(*option == 'm') opt |= FUSER_OPT_MOUNT;
  53                 else if(*option == 'k') opt |= FUSER_OPT_KILL;
  54                 else if(*option == 's') opt |= FUSER_OPT_SILENT;
  55                 else if(*option == '6') opt |= FUSER_OPT_IP6;
  56                 else if(*option == '4') opt |= FUSER_OPT_IP4;
  57                 else {
  58                         bb_error_msg_and_die(
  59                                 "Unsupported option '%c'", *option);
  60                 }
  61                 ++option;
  62         }
  63         return opt;
  64 }
  65
  66 static int fuser_file_to_dev_inode(const char *filename,
  67          dev_t *dev, ino_t *inode)
  68 {
  69         struct stat f_stat;
  70         if((stat(filename, &f_stat)) < 0) return 0;
  71         *inode = f_stat.st_ino;
  72         *dev = f_stat.st_dev;
  73         return 1;
  74 }
  75
  76 static int fuser_find_socket_dev(dev_t *dev) {
  77         int fd = socket(PF_INET, SOCK_DGRAM,0);
  78         struct stat buf;
  79
  80         if (fd >= 0 && (fstat(fd, &buf)) == 0) {
  81                 *dev =  buf.st_dev;
  82                 close(fd);
  83                 return 1;
  84         }
  85         return 0;
  86 }
  87
  88 static int fuser_parse_net_arg(const char *filename,
  89         const char **proto, int *port)
  90 {
  91         char path[sizeof(FUSER_PROC_DIR)+12], tproto[5];
  92
  93         if((sscanf(filename, "%d/%4s", port, tproto)) != 2) return 0;
  94         sprintf(path, "%s/net/%s", FUSER_PROC_DIR, tproto);
  95         if((access(path, R_OK)) != 0) return 0;
  96         *proto = bb_xstrdup(tproto);
  97         return 1;
  98 }
  99
 100 static int fuser_add_pid(pid_list *plist, pid_t pid)
 101 {
 102         pid_list *curr = NULL, *last = NULL;
 103
 104         if(plist->pid == 0) plist->pid = pid;
 105         curr = plist;
 106         while(curr != NULL) {
 107                 if(curr->pid == pid) return 1;
 108                 last = curr;
 109                 curr = curr->next;
 110         }
 111         curr = xmalloc(sizeof(pid_list));
 112         last->next = curr;
 113         curr->pid = pid;
 114         curr->next = NULL;
 115         return 1;
 116 }
 117
 118 static int fuser_add_inode(inode_list *ilist, dev_t dev, ino_t inode)
 119 {
 120         inode_list *curr = NULL, *last = NULL;
 121
 122         if(!ilist->inode && !ilist->dev) {
 123                 ilist->dev = dev;
 124                 ilist->inode = inode;
 125         }
 126         curr = ilist;
 127         while(curr != NULL) {
 128                 if(curr->inode == inode && curr->dev == dev) return 1;
 129                 last = curr;
 130                 curr = curr->next;
 131         }
 132         curr = xmalloc(sizeof(inode_list));
 133         last->next = curr;
 134         curr->dev = dev;
 135         curr->inode = inode;
 136         curr->next = NULL;
 137         return 1;
 138 }
 139
 140 static int fuser_scan_proc_net(int opts, const char *proto,
 141         int port, inode_list *ilist)
 142 {
 143         char path[sizeof(FUSER_PROC_DIR)+12], line[FUSER_MAX_LINE+1];
 144         char addr[128];
 145         ino_t tmp_inode;
 146         dev_t tmp_dev;
 147         long long  uint64_inode;
 148         int tmp_port;
 149         FILE *f;
 150
 151         if(!fuser_find_socket_dev(&tmp_dev)) tmp_dev = 0;
 152         sprintf(path, "%s/net/%s", FUSER_PROC_DIR, proto);
 153
 154         if (!(f = fopen(path, "r"))) return 0;
 155         while(fgets(line, FUSER_MAX_LINE, f)) {
 156                 if(sscanf(line,
 157                         "%*d: %64[0-9A-Fa-f]:%x %*x:%*x %*x %*x:%*x "
 158                         "%*x:%*x %*x %*d %*d %llu",
 159                         addr, &tmp_port, &uint64_inode) == 3) {
 160                         if((strlen(addr) == 8) &&
 161                                 (opts & FUSER_OPT_IP6)) continue;
 162                         else if((strlen(addr) > 8) &&
 163                                 (opts & FUSER_OPT_IP4)) continue;
 164                         if(tmp_port == port) {
 165                                 tmp_inode = uint64_inode;
 166                                 fuser_add_inode(ilist, tmp_dev, tmp_inode);
 167                         }
 168                 }
 169
 170         }
 171         fclose(f);
 172         return 1;
 173 }
 174
 175 static int fuser_search_dev_inode(int opts, inode_list *ilist,
 176         dev_t dev, ino_t inode)
 177 {
 178         inode_list *curr;
 179         curr = ilist;
 180
 181         while(curr) {
 182                 if((opts & FUSER_OPT_MOUNT) &&  curr->dev == dev)
 183                         return 1;
 184                 if(curr->inode == inode && curr->dev == dev)
 185                         return 1;
 186                 curr = curr->next;
 187         }
 188         return 0;
 189 }
 190
 191 static int fuser_scan_pid_maps(int opts, const char *fname, pid_t pid,
 192         inode_list *ilist, pid_list *plist)
 193 {
 194         FILE *file;
 195         char line[FUSER_MAX_LINE + 1];
 196         int major, minor;
 197         ino_t inode;
 198         long long uint64_inode;
 199         dev_t dev;
 200
 201         if (!(file = fopen(fname, "r"))) return 0;
 202         while (fgets(line, FUSER_MAX_LINE, file)) {
 203                 if(sscanf(line, "%*s %*s %*s %x:%x %llu",
 204                         &major, &minor, &uint64_inode) != 3) continue;
 205                 inode = uint64_inode;
 206                 if(major == 0 && minor == 0 && inode == 0) continue;
 207                 dev = makedev(major, minor);
 208                 if(fuser_search_dev_inode(opts, ilist, dev, inode)) {
 209                         fuser_add_pid(plist, pid);
 210                 }
 211
 212         }
 213         fclose(file);
 214         return 1;
 215 }
 216
 217 static int fuser_scan_link(int opts, const char *lname, pid_t pid,
 218         inode_list *ilist, pid_list *plist)
 219 {
 220         ino_t inode;
 221         dev_t dev;
 222
 223         if(!fuser_file_to_dev_inode(lname, &dev, &inode)) return 0;
 224         if(fuser_search_dev_inode(opts, ilist, dev, inode))
 225                 fuser_add_pid(plist, pid);
 226         return 1;
 227 }
 228
 229 static int fuser_scan_dir_links(int opts, const char *dname, pid_t pid,
 230         inode_list *ilist, pid_list *plist)
 231 {
 232         DIR *d;
 233         struct dirent *de;
 234         char *lname;
 235
 236         if((d = opendir(dname))) {
 237                 while((de = readdir(d)) != NULL) {
 238                         lname = concat_subpath_file(dname, de->d_name);
 239                         if(lname == NULL)
 240                                 continue;
 241                         fuser_scan_link(opts, lname, pid, ilist, plist);
 242                         free(lname);
 243                 }
 244                 closedir(d);
 245         }
 246         else return 0;
 247         return 1;
 248
 249 }
 250
 251 static int fuser_scan_proc_pids(int opts, inode_list *ilist, pid_list *plist)
 252 {
 253         DIR *d;
 254         struct dirent *de;
 255         pid_t pid;
 256         char *dname;
 257
 258         if(!(d = opendir(FUSER_PROC_DIR))) return 0;
 259         while((de = readdir(d)) != NULL) {
 260                 pid = (pid_t)atoi(de->d_name);
 261                 if(!pid) continue;
 262                 dname = concat_subpath_file(FUSER_PROC_DIR, de->d_name);
 263                 if(chdir(dname) < 0) {
 264                         free(dname);
 265                         continue;
 266                 }
 267                 free(dname);
 268                 fuser_scan_link(opts, "cwd", pid, ilist, plist);
 269                 fuser_scan_link(opts, "exe", pid, ilist, plist);
 270                 fuser_scan_link(opts, "root", pid, ilist, plist);
 271                 fuser_scan_dir_links(opts, "fd", pid, ilist, plist);
 272                 fuser_scan_dir_links(opts, "lib", pid, ilist, plist);
 273                 fuser_scan_dir_links(opts, "mmap", pid, ilist, plist);
 274                 fuser_scan_pid_maps(opts, "maps", pid, ilist, plist);
 275                 chdir("..");
 276         }
 277         closedir(d);
 278         return 1;
 279 }
 280
 281 static int fuser_print_pid_list(pid_list *plist) {
 282         pid_list *curr = plist;
 283
 284         if(plist == NULL) return 0;
 285         while(curr != NULL) {
 286                 if(curr->pid > 0) printf("%d ", curr->pid);
 287                 curr = curr->next;
 288         }
 289         printf("\n");
 290         return 1;
 291 }
 292
 293 static int fuser_kill_pid_list(pid_list *plist, int sig) {
 294         pid_list *curr = plist;
 295         pid_t mypid = getpid();
 296         int success = 1;
 297
 298         if(plist == NULL) return 0;
 299         while(curr != NULL) {
 300                 if(curr->pid > 0 && curr->pid != mypid) {
 301                         if (kill(curr->pid, sig) != 0) {
 302                                 bb_perror_msg(
 303                                         "Could not kill pid '%d'", curr->pid);
 304                                 success = 0;
 305                         }
 306                 }
 307                 curr = curr->next;
 308         }
 309         return success;
 310 }
 311
 312 extern int fuser_main(int argc, char **argv) {
 313         int port, i, optn;
 314         int* fni; /* file name indexes of argv */
 315         int fnic = 0;  /* file name index count */
 316         const char *proto;
 317         static int opt = 0; /* FUSER_OPT_ */
 318         dev_t dev;
 319         ino_t inode;
 320         pid_list *pids;
 321         inode_list *inodes;
 322         int killsig = SIGTERM;
 323         int success = 1;
 324
 325         fni = xmalloc(sizeof(int));
 326         for(i=1;i<argc;i++) {
 327                 optn = fuser_option(argv[i]);
 328                 if(optn) opt |= optn;
 329                 else if(argv[i][0] == '-') {
 330                         if(!(u_signal_names(argv[i]+1, &killsig, 0)))
 331                                 killsig = SIGTERM;
 332                 }
 333                 else {
 334                         fni = xrealloc(fni, sizeof(int) * (fnic+2));
 335                         fni[fnic++] = i;
 336                 }
 337         }
 338         if(!fnic) return 1;
 339
 340         pids = xmalloc(sizeof(pid_list));
 341         inodes = xmalloc(sizeof(inode_list));
 342         for(i=0;i<fnic;i++) {
 343                 if(fuser_parse_net_arg(argv[fni[i]], &proto, &port)) {
 344                         fuser_scan_proc_net(opt, proto, port, inodes);
 345                 }
 346                 else {
 347                         if(!fuser_file_to_dev_inode(
 348                                 argv[fni[i]], &dev, &inode)) {
 349                                 free(pids);
 350                                 free(inodes);
 351                                 bb_perror_msg_and_die(
 352                                         "Could not open '%s'", argv[fni[i]]);
 353                         }
 354                         fuser_add_inode(inodes, dev, inode);
 355                 }
 356         }
 357         success = fuser_scan_proc_pids(opt, inodes, pids);
 358         /* if the first pid in the list is 0, none have been found */
 359         if(pids->pid == 0) success = 0;
 360         if(success) {
 361                 if(opt & FUSER_OPT_KILL) {
 362                         success = fuser_kill_pid_list(pids, killsig);
 363                 }
 364                 else if(!(opt & FUSER_OPT_SILENT)) {
 365                         success = fuser_print_pid_list(pids);
 366                 }
 367         }
 368         free(pids);
 369         free(inodes);
 370         /* return 0 on (success == 1) 1 otherwise */
 371         return (success != 1);
 372 }