sys-utils/lsns.c

   1 /*
   2  * lsns(8) - list system namespaces
   3  *
   4  * Copyright (C) 2015 Karel Zak <kzak@redhat.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it would be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <getopt.h>
  23 #include <stdlib.h>
  24 #include <assert.h>
  25 #include <dirent.h>
  26 #include <unistd.h>
  27 #include <sys/stat.h>
  28 #include <sys/types.h>
  29 #include <wchar.h>
  30 #include <libsmartcols.h>
  31 #include <libmount.h>
  32
  33 #ifdef HAVE_LINUX_NET_NAMESPACE_H
  34 #include <stdbool.h>
  35 #include <sys/socket.h>
  36 #include <linux/netlink.h>
  37 #include <linux/rtnetlink.h>
  38 #include <linux/net_namespace.h>
  39 #endif
  40
  41 #include "pathnames.h"
  42 #include "nls.h"
  43 #include "xalloc.h"
  44 #include "c.h"
  45 #include "list.h"
  46 #include "closestream.h"
  47 #include "optutils.h"
  48 #include "procutils.h"
  49 #include "strutils.h"
  50 #include "namespace.h"
  51 #include "path.h"
  52 #include "idcache.h"
  53
  54 #include "debug.h"
  55
  56 static UL_DEBUG_DEFINE_MASK(lsns);
  57 UL_DEBUG_DEFINE_MASKNAMES(lsns) = UL_DEBUG_EMPTY_MASKNAMES;
  58
  59 #define LSNS_DEBUG_INIT         (1 << 1)
  60 #define LSNS_DEBUG_PROC         (1 << 2)
  61 #define LSNS_DEBUG_NS           (1 << 3)
  62 #define LSNS_DEBUG_ALL          0xFFFF
  63
  64 #define LSNS_NETNS_UNUSABLE -2
  65
  66 #define DBG(m, x)       __UL_DBG(lsns, LSNS_DEBUG_, m, x)
  67 #define ON_DBG(m, x)    __UL_DBG_CALL(lsns, LSNS_DEBUG_, m, x)
  68
  69 static struct idcache *uid_cache = NULL;
  70
  71 /* column IDs */
  72 enum {
  73         COL_NS = 0,
  74         COL_TYPE,
  75         COL_PATH,
  76         COL_NPROCS,
  77         COL_PID,
  78         COL_PPID,
  79         COL_COMMAND,
  80         COL_UID,
  81         COL_USER,
  82         COL_NETNSID,
  83         COL_NSFS,
  84 };
  85
  86 /* column names */
  87 struct colinfo {
  88         const char *name; /* header */
  89         double     whint; /* width hint (N < 1 is in percent of termwidth) */
  90         int        flags; /* SCOLS_FL_* */
  91         const char *help;
  92 };
  93
  94 /* columns descriptions */
  95 static const struct colinfo infos[] = {
  96         [COL_NS]      = { "NS",     10, SCOLS_FL_RIGHT, N_("namespace identifier (inode number)") },
  97         [COL_TYPE]    = { "TYPE",    5, 0, N_("kind of namespace") },
  98         [COL_PATH]    = { "PATH",    0, 0, N_("path to the namespace")},
  99         [COL_NPROCS]  = { "NPROCS",  5, SCOLS_FL_RIGHT, N_("number of processes in the namespace") },
 100         [COL_PID]     = { "PID",     5, SCOLS_FL_RIGHT, N_("lowest PID in the namespace") },
 101         [COL_PPID]    = { "PPID",    5, SCOLS_FL_RIGHT, N_("PPID of the PID") },
 102         [COL_COMMAND] = { "COMMAND", 0, SCOLS_FL_TRUNC, N_("command line of the PID")},
 103         [COL_UID]     = { "UID",     0, SCOLS_FL_RIGHT, N_("UID of the PID")},
 104         [COL_USER]    = { "USER",    0, 0, N_("username of the PID")},
 105         [COL_NETNSID] = { "NETNSID", 0, SCOLS_FL_RIGHT, N_("Net namespace ID")},
 106         [COL_NSFS]    = { "NSFS",    0, SCOLS_FL_WRAP, N_("Logical name established by nsfs")}
 107 };
 108
 109 static int columns[ARRAY_SIZE(infos) * 2];
 110 static size_t ncolumns;
 111
 112 enum {
 113         LSNS_ID_MNT = 0,
 114         LSNS_ID_NET,
 115         LSNS_ID_PID,
 116         LSNS_ID_UTS,
 117         LSNS_ID_IPC,
 118         LSNS_ID_USER,
 119         LSNS_ID_CGROUP
 120 };
 121
 122 static char *ns_names[] = {
 123         [LSNS_ID_MNT] = "mnt",
 124         [LSNS_ID_NET] = "net",
 125         [LSNS_ID_PID] = "pid",
 126         [LSNS_ID_UTS] = "uts",
 127         [LSNS_ID_IPC] = "ipc",
 128         [LSNS_ID_USER] = "user",
 129         [LSNS_ID_CGROUP] = "cgroup"
 130 };
 131
 132 struct lsns_namespace {
 133         ino_t id;
 134         int type;                       /* LSNS_* */
 135         int nprocs;
 136         int netnsid;
 137
 138         struct lsns_process *proc;
 139
 140         struct list_head namespaces;    /* lsns->processes member */
 141         struct list_head processes;     /* head of lsns_process *siblings */
 142 };
 143
 144 struct lsns_process {
 145         pid_t pid;              /* process PID */
 146         pid_t ppid;             /* parent's PID */
 147         pid_t tpid;             /* thread group */
 148         char state;
 149         uid_t uid;
 150
 151         ino_t            ns_ids[ARRAY_SIZE(ns_names)];
 152         struct list_head ns_siblings[ARRAY_SIZE(ns_names)];
 153
 154         struct list_head processes;     /* list of processes */
 155
 156         struct libscols_line *outline;
 157         struct lsns_process *parent;
 158
 159         int netnsid;
 160 };
 161
 162 struct lsns {
 163         struct list_head processes;
 164         struct list_head namespaces;
 165
 166         pid_t   fltr_pid;       /* filter out by PID */
 167         ino_t   fltr_ns;        /* filter out by namespace */
 168         int     fltr_types[ARRAY_SIZE(ns_names)];
 169         int     fltr_ntypes;
 170
 171         unsigned int raw        : 1,
 172                      json       : 1,
 173                      tree       : 1,
 174                      list       : 1,
 175                      no_trunc   : 1,
 176                      no_headings: 1,
 177                      no_wrap    : 1;
 178
 179         struct libmnt_table *tab;
 180 };
 181
 182 struct netnsid_cache {
 183         ino_t ino;
 184         int   id;
 185         struct list_head netnsids;
 186 };
 187
 188 static struct list_head netnsids_cache;
 189
 190 static int netlink_fd = -1;
 191
 192 static void lsns_init_debug(void)
 193 {
 194         __UL_INIT_DEBUG(lsns, LSNS_DEBUG_, 0, LSNS_DEBUG);
 195 }
 196
 197 static int ns_name2type(const char *name)
 198 {
 199         size_t i;
 200
 201         for (i = 0; i < ARRAY_SIZE(ns_names); i++) {
 202                 if (strcmp(ns_names[i], name) == 0)
 203                         return i;
 204         }
 205         return -1;
 206 }
 207
 208 static int column_name_to_id(const char *name, size_t namesz)
 209 {
 210         size_t i;
 211
 212         assert(name);
 213
 214         for (i = 0; i < ARRAY_SIZE(infos); i++) {
 215                 const char *cn = infos[i].name;
 216
 217                 if (!strncasecmp(name, cn, namesz) && !*(cn + namesz))
 218                         return i;
 219         }
 220         warnx(_("unknown column: %s"), name);
 221         return -1;
 222 }
 223
 224 static inline int get_column_id(int num)
 225 {
 226         assert(num >= 0);
 227         assert((size_t) num < ncolumns);
 228         assert(columns[num] < (int) ARRAY_SIZE(infos));
 229
 230         return columns[num];
 231 }
 232
 233 static inline const struct colinfo *get_column_info(unsigned num)
 234 {
 235         return &infos[ get_column_id(num) ];
 236 }
 237
 238 static int get_ns_ino(int dir, const char *nsname, ino_t *ino)
 239 {
 240         struct stat st;
 241         char path[16];
 242
 243         snprintf(path, sizeof(path), "ns/%s", nsname);
 244
 245         if (fstatat(dir, path, &st, 0) != 0)
 246                 return -errno;
 247         *ino = st.st_ino;
 248         return 0;
 249 }
 250
 251 static int parse_proc_stat(FILE *fp, pid_t *pid, char *state, pid_t *ppid)
 252 {
 253         char *line = NULL, *p;
 254         size_t len = 0;
 255         int rc;
 256
 257         if (getline(&line, &len, fp) < 0) {
 258                 rc = -errno;
 259                 goto error;
 260         }
 261
 262         p = strrchr(line, ')');
 263         if (p == NULL ||
 264             sscanf(line, "%d (", pid) != 1 ||
 265             sscanf(p, ") %c %d*[^\n]", state, ppid) != 2) {
 266                 rc = -EINVAL;
 267                 goto error;
 268         }
 269         rc = 0;
 270
 271 error:
 272         free(line);
 273         return rc;
 274 }
 275
 276 #ifdef HAVE_LINUX_NET_NAMESPACE_H
 277 static int netnsid_cache_find(ino_t netino, int *netnsid)
 278 {
 279         struct list_head *p;
 280
 281         list_for_each(p, &netnsids_cache) {
 282                 struct netnsid_cache *e = list_entry(p,
 283                                                      struct netnsid_cache,
 284                                                      netnsids);
 285                 if (e->ino == netino) {
 286                         *netnsid = e->id;
 287                         return 1;
 288                 }
 289         }
 290
 291         return 0;
 292 }
 293
 294 static void netnsid_cache_add(ino_t netino, int netnsid)
 295 {
 296         struct netnsid_cache *e;
 297
 298         e = xcalloc(1, sizeof(*e));
 299         e->ino = netino;
 300         e->id  = netnsid;
 301         INIT_LIST_HEAD(&e->netnsids);
 302         list_add(&e->netnsids, &netnsids_cache);
 303 }
 304
 305 static int get_netnsid_via_netlink_send_request(int target_fd)
 306 {
 307         unsigned char req[NLMSG_SPACE(sizeof(struct rtgenmsg))
 308                           + RTA_SPACE(sizeof(int32_t))];
 309
 310         struct nlmsghdr *nlh = (struct nlmsghdr *)req;
 311         struct rtgenmsg *rt = NLMSG_DATA(req);
 312         struct rtattr *rta = (struct rtattr *)
 313                 (req + NLMSG_SPACE(sizeof(struct rtgenmsg)));
 314         int32_t *fd = RTA_DATA(rta);
 315
 316         nlh->nlmsg_len = sizeof(req);
 317         nlh->nlmsg_flags = NLM_F_REQUEST;
 318         nlh->nlmsg_type = RTM_GETNSID;
 319         rt->rtgen_family = AF_UNSPEC;
 320         rta->rta_type = NETNSA_FD;
 321         rta->rta_len = RTA_SPACE(sizeof(int32_t));
 322         *fd = target_fd;
 323
 324         if (send(netlink_fd, req, sizeof(req), 0) < 0)
 325                 return -1;
 326         return 0;
 327 }
 328
 329 static int get_netnsid_via_netlink_recv_response(int *netnsid)
 330 {
 331         unsigned char res[NLMSG_SPACE(sizeof(struct rtgenmsg))
 332                           + ((RTA_SPACE(sizeof(int32_t))
 333                               < RTA_SPACE(sizeof(struct nlmsgerr)))
 334                              ? RTA_SPACE(sizeof(struct nlmsgerr))
 335                              : RTA_SPACE(sizeof(int32_t)))];
 336         int reslen, rtalen;
 337
 338         struct nlmsghdr *nlh;
 339         struct rtattr *rta;
 340
 341         reslen = recv(netlink_fd, res, sizeof(res), 0);
 342         if (reslen < 0)
 343                 return -1;
 344
 345         nlh = (struct nlmsghdr *)res;
 346         if (!(NLMSG_OK(nlh, reslen)
 347               && nlh->nlmsg_type == RTM_NEWNSID))
 348                 return -1;
 349
 350         rtalen = NLMSG_PAYLOAD(nlh, sizeof(struct rtgenmsg));
 351         rta = (struct rtattr *)(res + NLMSG_SPACE(sizeof(struct rtgenmsg)));
 352         if (!(RTA_OK(rta, rtalen)
 353               && rta->rta_type == NETNSA_NSID))
 354                 return -1;
 355
 356         *netnsid = *(int *)RTA_DATA(rta);
 357
 358         return 0;
 359 }
 360
 361 static int get_netnsid_via_netlink(int dir, const char *path)
 362 {
 363         int netnsid;
 364         int target_fd;
 365
 366         if (netlink_fd < 0)
 367                 return LSNS_NETNS_UNUSABLE;
 368
 369         target_fd = openat(dir, path, O_RDONLY);
 370         if (target_fd < 0)
 371                 return LSNS_NETNS_UNUSABLE;
 372
 373         if (get_netnsid_via_netlink_send_request(target_fd) < 0) {
 374                 netnsid = LSNS_NETNS_UNUSABLE;
 375                 goto out;
 376         }
 377
 378         if (get_netnsid_via_netlink_recv_response(&netnsid) < 0) {
 379                 netnsid = LSNS_NETNS_UNUSABLE;
 380                 goto out;
 381         }
 382
 383  out:
 384         close(target_fd);
 385         return netnsid;
 386 }
 387
 388 static int get_netnsid(int dir, ino_t netino)
 389 {
 390         int netnsid;
 391
 392         if (!netnsid_cache_find(netino, &netnsid)) {
 393                 netnsid = get_netnsid_via_netlink(dir, "ns/net");
 394                 netnsid_cache_add(netino, netnsid);
 395         }
 396
 397         return netnsid;
 398 }
 399 #else
 400 static int get_netnsid(int dir __attribute__((__unused__)),
 401                        ino_t netino __attribute__((__unused__)))
 402 {
 403         return LSNS_NETNS_UNUSABLE;
 404 }
 405 #endif /* HAVE_LINUX_NET_NAMESPACE_H */
 406
 407 static int read_process(struct lsns *ls, pid_t pid)
 408 {
 409         struct lsns_process *p = NULL;
 410         char buf[BUFSIZ];
 411         DIR *dir;
 412         int rc = 0, fd;
 413         FILE *f = NULL;
 414         size_t i;
 415         struct stat st;
 416
 417         DBG(PROC, ul_debug("reading %d", (int) pid));
 418
 419         snprintf(buf, sizeof(buf), "/proc/%d", pid);
 420         dir = opendir(buf);
 421         if (!dir)
 422                 return -errno;
 423
 424         p = xcalloc(1, sizeof(*p));
 425         if (!p) {
 426                 rc = -ENOMEM;
 427                 goto done;
 428         }
 429         p->netnsid = LSNS_NETNS_UNUSABLE;
 430
 431         if (fstat(dirfd(dir), &st) == 0) {
 432                 p->uid = st.st_uid;
 433                 add_uid(uid_cache, st.st_uid);
 434         }
 435
 436         fd = openat(dirfd(dir), "stat", O_RDONLY);
 437         if (fd < 0) {
 438                 rc = -errno;
 439                 goto done;
 440         }
 441         if (!(f = fdopen(fd, "r"))) {
 442                 rc = -errno;
 443                 goto done;
 444         }
 445         rc = parse_proc_stat(f, &p->pid, &p->state, &p->ppid);
 446         if (rc < 0)
 447                 goto done;
 448         rc = 0;
 449
 450         for (i = 0; i < ARRAY_SIZE(p->ns_ids); i++) {
 451                 INIT_LIST_HEAD(&p->ns_siblings[i]);
 452
 453                 if (!ls->fltr_types[i])
 454                         continue;
 455
 456                 rc = get_ns_ino(dirfd(dir), ns_names[i], &p->ns_ids[i]);
 457                 if (rc && rc != -EACCES && rc != -ENOENT)
 458                         goto done;
 459                 if (i == LSNS_ID_NET)
 460                         p->netnsid = get_netnsid(dirfd(dir), p->ns_ids[i]);
 461                 rc = 0;
 462         }
 463
 464         INIT_LIST_HEAD(&p->processes);
 465
 466         DBG(PROC, ul_debugobj(p, "new pid=%d", p->pid));
 467         list_add_tail(&p->processes, &ls->processes);
 468 done:
 469         if (f)
 470                 fclose(f);
 471         closedir(dir);
 472         if (rc)
 473                 free(p);
 474         return rc;
 475 }
 476
 477 static int read_processes(struct lsns *ls)
 478 {
 479         struct proc_processes *proc = NULL;
 480         pid_t pid;
 481         int rc = 0;
 482
 483         DBG(PROC, ul_debug("opening /proc"));
 484
 485         if (!(proc = proc_open_processes())) {
 486                 rc = -errno;
 487                 goto done;
 488         }
 489
 490         while (proc_next_pid(proc, &pid) == 0) {
 491                 rc = read_process(ls, pid);
 492                 if (rc && rc != -EACCES && rc != -ENOENT)
 493                         break;
 494                 rc = 0;
 495         }
 496 done:
 497         DBG(PROC, ul_debug("closing /proc"));
 498         proc_close_processes(proc);
 499         return rc;
 500 }
 501
 502 static struct lsns_namespace *get_namespace(struct lsns *ls, ino_t ino)
 503 {
 504         struct list_head *p;
 505
 506         list_for_each(p, &ls->namespaces) {
 507                 struct lsns_namespace *ns = list_entry(p, struct lsns_namespace, namespaces);
 508
 509                 if (ns->id == ino)
 510                         return ns;
 511         }
 512         return NULL;
 513 }
 514
 515 static int namespace_has_process(struct lsns_namespace *ns, pid_t pid)
 516 {
 517         struct list_head *p;
 518
 519         list_for_each(p, &ns->processes) {
 520                 struct lsns_process *proc = list_entry(p, struct lsns_process, ns_siblings[ns->type]);
 521
 522                 if (proc->pid == pid)
 523                         return 1;
 524         }
 525         return 0;
 526 }
 527
 528 static struct lsns_namespace *add_namespace(struct lsns *ls, int type, ino_t ino)
 529 {
 530         struct lsns_namespace *ns = xcalloc(1, sizeof(*ns));
 531
 532         if (!ns)
 533                 return NULL;
 534
 535         DBG(NS, ul_debugobj(ns, "new %s[%ju]", ns_names[type], (uintmax_t)ino));
 536
 537         INIT_LIST_HEAD(&ns->processes);
 538         INIT_LIST_HEAD(&ns->namespaces);
 539
 540         ns->type = type;
 541         ns->id = ino;
 542
 543         list_add_tail(&ns->namespaces, &ls->namespaces);
 544         return ns;
 545 }
 546
 547 static int add_process_to_namespace(struct lsns *ls, struct lsns_namespace *ns, struct lsns_process *proc)
 548 {
 549         struct list_head *p;
 550
 551         DBG(NS, ul_debugobj(ns, "add process [%p] pid=%d to %s[%ju]",
 552                 proc, proc->pid, ns_names[ns->type], (uintmax_t)ns->id));
 553
 554         list_for_each(p, &ls->processes) {
 555                 struct lsns_process *xproc = list_entry(p, struct lsns_process, processes);
 556
 557                 if (xproc->pid == proc->ppid)           /* my parent */
 558                         proc->parent = xproc;
 559                 else if (xproc->ppid == proc->pid)      /* my child */
 560                         xproc->parent = proc;
 561         }
 562
 563         list_add_tail(&proc->ns_siblings[ns->type], &ns->processes);
 564         ns->nprocs++;
 565
 566         if (!ns->proc || ns->proc->pid > proc->pid)
 567                 ns->proc = proc;
 568
 569         return 0;
 570 }
 571
 572 static int cmp_namespaces(struct list_head *a, struct list_head *b,
 573                           __attribute__((__unused__)) void *data)
 574 {
 575         struct lsns_namespace *xa = list_entry(a, struct lsns_namespace, namespaces),
 576                               *xb = list_entry(b, struct lsns_namespace, namespaces);
 577
 578         return cmp_numbers(xa->id, xb->id);
 579 }
 580
 581 static int netnsid_xasputs(char **str, int netnsid)
 582 {
 583         if (netnsid >= 0)
 584                 return xasprintf(str, "%d", netnsid);
 585 #ifdef NETNSA_NSID_NOT_ASSIGNED
 586         else if (netnsid == NETNSA_NSID_NOT_ASSIGNED)
 587                 return xasprintf(str, "%s", "unassigned");
 588 #endif
 589         else
 590                 return 0;
 591 }
 592
 593 static int read_namespaces(struct lsns *ls)
 594 {
 595         struct list_head *p;
 596
 597         DBG(NS, ul_debug("reading namespace"));
 598
 599         list_for_each(p, &ls->processes) {
 600                 size_t i;
 601                 struct lsns_namespace *ns;
 602                 struct lsns_process *proc = list_entry(p, struct lsns_process, processes);
 603
 604                 for (i = 0; i < ARRAY_SIZE(proc->ns_ids); i++) {
 605                         if (proc->ns_ids[i] == 0)
 606                                 continue;
 607                         if (!(ns = get_namespace(ls, proc->ns_ids[i]))) {
 608                                 ns = add_namespace(ls, i, proc->ns_ids[i]);
 609                                 if (!ns)
 610                                         return -ENOMEM;
 611                         }
 612                         add_process_to_namespace(ls, ns, proc);
 613                 }
 614         }
 615
 616         list_sort(&ls->namespaces, cmp_namespaces, NULL);
 617
 618         return 0;
 619 }
 620
 621 static int is_nsfs_root(struct libmnt_fs *fs, void *data)
 622 {
 623         if (!mnt_fs_match_fstype(fs, "nsfs") || !mnt_fs_get_root(fs))
 624                 return 0;
 625
 626         return (strcmp(mnt_fs_get_root(fs), (char *)data) == 0);
 627 }
 628
 629 static int is_path_included(const char *path_set, const char *elt,
 630                               const char sep)
 631 {
 632         size_t elt_len;
 633         size_t path_set_len;
 634         char *tmp;
 635
 636
 637         tmp = strstr(path_set, elt);
 638         if (!tmp)
 639                 return 0;
 640
 641         elt_len = strlen(elt);
 642         path_set_len = strlen(path_set);
 643
 644         /* path_set includes only elt or
 645          * path_set includes elt as the first element.
 646          */
 647         if (tmp == path_set
 648             && ((path_set_len == elt_len)
 649                 || (path_set[elt_len] == sep)))
 650                 return 1;
 651
 652         /* path_set includes elt at the middle
 653          * or as the last element.
 654          */
 655         if ((*(tmp - 1) == sep)
 656             && ((*(tmp + elt_len) == sep)
 657                 || (*(tmp + elt_len) == '\0')))
 658                 return 1;
 659
 660         return 0;
 661 }
 662
 663 static int nsfs_xasputs(char **str,
 664                         struct lsns_namespace *ns,
 665                         struct libmnt_table *tab,
 666                         char sep)
 667 {
 668         struct libmnt_iter *itr = mnt_new_iter(MNT_ITER_FORWARD);
 669         char *expected_root;
 670         struct libmnt_fs *fs = NULL;
 671
 672         xasprintf(&expected_root, "%s:[%lu]", ns_names[ns->type], ns->id);
 673         *str = NULL;
 674
 675         while (mnt_table_find_next_fs(tab, itr, is_nsfs_root,
 676                                       expected_root, &fs) == 0) {
 677
 678                 const char *tgt = mnt_fs_get_target(fs);
 679
 680                 if (!*str)
 681                         xasprintf(str, "%s", tgt);
 682
 683                 else if (!is_path_included(*str, tgt, sep)) {
 684                         char *tmp = NULL;
 685
 686                         xasprintf(&tmp, "%s%c%s", *str, sep, tgt);
 687                         free(*str);
 688                         *str = tmp;
 689                 }
 690         }
 691         free(expected_root);
 692         mnt_free_iter(itr);
 693
 694         return 1;
 695 }
 696 static void add_scols_line(struct lsns *ls, struct libscols_table *table,
 697                            struct lsns_namespace *ns, struct lsns_process *proc)
 698 {
 699         size_t i;
 700         struct libscols_line *line;
 701
 702         assert(ns);
 703         assert(table);
 704
 705         line = scols_table_new_line(table,
 706                         ls->tree && proc->parent ? proc->parent->outline : NULL);
 707         if (!line) {
 708                 warn(_("failed to add line to output"));
 709                 return;
 710         }
 711
 712         for (i = 0; i < ncolumns; i++) {
 713                 char *str = NULL;
 714
 715                 switch (get_column_id(i)) {
 716                 case COL_NS:
 717                         xasprintf(&str, "%ju", (uintmax_t)ns->id);
 718                         break;
 719                 case COL_PID:
 720                         xasprintf(&str, "%d", (int) proc->pid);
 721                         break;
 722                 case COL_PPID:
 723                         xasprintf(&str, "%d", (int) proc->ppid);
 724                         break;
 725                 case COL_TYPE:
 726                         xasprintf(&str, "%s", ns_names[ns->type]);
 727                         break;
 728                 case COL_NPROCS:
 729                         xasprintf(&str, "%d", ns->nprocs);
 730                         break;
 731                 case COL_COMMAND:
 732                         str = proc_get_command(proc->pid);
 733                         if (!str)
 734                                 str = proc_get_command_name(proc->pid);
 735                         break;
 736                 case COL_PATH:
 737                         xasprintf(&str, "/proc/%d/ns/%s", (int) proc->pid, ns_names[ns->type]);
 738                         break;
 739                 case COL_UID:
 740                         xasprintf(&str, "%d", (int) proc->uid);
 741                         break;
 742                 case COL_USER:
 743                         xasprintf(&str, "%s", get_id(uid_cache, proc->uid)->name);
 744                         break;
 745                 case COL_NETNSID:
 746                         if (ns->type == LSNS_ID_NET)
 747                                 netnsid_xasputs(&str, proc->netnsid);
 748                         break;
 749                 case COL_NSFS:
 750                         nsfs_xasputs(&str, ns, ls->tab, ls->no_wrap ? ',' : '\n');
 751                         break;
 752                 default:
 753                         break;
 754                 }
 755
 756                 if (str && scols_line_refer_data(line, i, str) != 0)
 757                         err_oom();
 758         }
 759
 760         proc->outline = line;
 761 }
 762
 763 static struct libscols_table *init_scols_table(struct lsns *ls)
 764 {
 765         struct libscols_table *tab;
 766         size_t i;
 767
 768         tab = scols_new_table();
 769         if (!tab) {
 770                 warn(_("failed to initialize output table"));
 771                 return NULL;
 772         }
 773
 774         scols_table_enable_raw(tab, ls->raw);
 775         scols_table_enable_json(tab, ls->json);
 776         scols_table_enable_noheadings(tab, ls->no_headings);
 777
 778         if (ls->json)
 779                 scols_table_set_name(tab, "namespaces");
 780
 781         for (i = 0; i < ncolumns; i++) {
 782                 const struct colinfo *col = get_column_info(i);
 783                 int flags = col->flags;
 784                 struct libscols_column *cl;
 785
 786                 if (ls->no_trunc)
 787                        flags &= ~SCOLS_FL_TRUNC;
 788                 if (ls->tree && get_column_id(i) == COL_COMMAND)
 789                         flags |= SCOLS_FL_TREE;
 790                 if (ls->no_wrap)
 791                         flags &= ~SCOLS_FL_WRAP;
 792
 793                 cl = scols_table_new_column(tab, col->name, col->whint, flags);
 794                 if (cl == NULL) {
 795                         warnx(_("failed to initialize output column"));
 796                         goto err;
 797                 }
 798                 if (!ls->no_wrap && get_column_id(i) == COL_NSFS) {
 799                         scols_column_set_wrapfunc(cl,
 800                                                   scols_wrapnl_chunksize,
 801                                                   scols_wrapnl_nextchunk,
 802                                                   NULL);
 803                         scols_column_set_safechars(cl, "\n");
 804                 }
 805         }
 806
 807         return tab;
 808 err:
 809         scols_unref_table(tab);
 810         return NULL;
 811 }
 812
 813 static int show_namespaces(struct lsns *ls)
 814 {
 815         struct libscols_table *tab;
 816         struct list_head *p;
 817         int rc = 0;
 818
 819         tab = init_scols_table(ls);
 820         if (!tab)
 821                 return -ENOMEM;
 822
 823         list_for_each(p, &ls->namespaces) {
 824                 struct lsns_namespace *ns = list_entry(p, struct lsns_namespace, namespaces);
 825
 826                 if (ls->fltr_pid != 0 && !namespace_has_process(ns, ls->fltr_pid))
 827                         continue;
 828
 829                 add_scols_line(ls, tab, ns, ns->proc);
 830         }
 831
 832         scols_print_table(tab);
 833         scols_unref_table(tab);
 834         return rc;
 835 }
 836
 837 static void show_process(struct lsns *ls, struct libscols_table *tab,
 838                          struct lsns_process *proc, struct lsns_namespace *ns)
 839 {
 840         /*
 841          * create a tree from parent->child relation, but only if the parent is
 842          * within the same namespace
 843          */
 844         if (ls->tree
 845             && proc->parent
 846             && !proc->parent->outline
 847             && proc->parent->ns_ids[ns->type] == proc->ns_ids[ns->type])
 848                 show_process(ls, tab, proc->parent, ns);
 849
 850         add_scols_line(ls, tab, ns, proc);
 851 }
 852
 853
 854 static int show_namespace_processes(struct lsns *ls, struct lsns_namespace *ns)
 855 {
 856         struct libscols_table *tab;
 857         struct list_head *p;
 858
 859         tab = init_scols_table(ls);
 860         if (!tab)
 861                 return -ENOMEM;
 862
 863         list_for_each(p, &ns->processes) {
 864                 struct lsns_process *proc = list_entry(p, struct lsns_process, ns_siblings[ns->type]);
 865
 866                 if (!proc->outline)
 867                         show_process(ls, tab, proc, ns);
 868         }
 869
 870
 871         scols_print_table(tab);
 872         scols_unref_table(tab);
 873         return 0;
 874 }
 875
 876 static void __attribute__((__noreturn__)) usage(void)
 877 {
 878         FILE *out = stdout;
 879         size_t i;
 880
 881         fputs(USAGE_HEADER, out);
 882
 883         fprintf(out,
 884                 _(" %s [options] [<namespace>]\n"), program_invocation_short_name);
 885
 886         fputs(USAGE_SEPARATOR, out);
 887         fputs(_("List system namespaces.\n"), out);
 888
 889         fputs(USAGE_OPTIONS, out);
 890         fputs(_(" -J, --json             use JSON output format\n"), out);
 891         fputs(_(" -l, --list             use list format output\n"), out);
 892         fputs(_(" -n, --noheadings       don't print headings\n"), out);
 893         fputs(_(" -o, --output <list>    define which output columns to use\n"), out);
 894         fputs(_(" -p, --task <pid>       print process namespaces\n"), out);
 895         fputs(_(" -r, --raw              use the raw output format\n"), out);
 896         fputs(_(" -u, --notruncate       don't truncate text in columns\n"), out);
 897         fputs(_(" -W, --nowrap           don't use multi-line representation\n"), out);
 898         fputs(_(" -t, --type <name>      namespace type (mnt, net, ipc, user, pid, uts, cgroup)\n"), out);
 899
 900         fputs(USAGE_SEPARATOR, out);
 901         printf(USAGE_HELP_OPTIONS(24));
 902
 903         fputs(USAGE_COLUMNS, out);
 904         for (i = 0; i < ARRAY_SIZE(infos); i++)
 905                 fprintf(out, " %11s  %s\n", infos[i].name, _(infos[i].help));
 906
 907         printf(USAGE_MAN_TAIL("lsns(8)"));
 908
 909         exit(EXIT_SUCCESS);
 910 }
 911
 912
 913 int main(int argc, char *argv[])
 914 {
 915         struct lsns ls;
 916         int c;
 917         int r = 0;
 918         char *outarg = NULL;
 919         static const struct option long_opts[] = {
 920                 { "json",       no_argument,       NULL, 'J' },
 921                 { "task",       required_argument, NULL, 'p' },
 922                 { "help",       no_argument,       NULL, 'h' },
 923                 { "output",     required_argument, NULL, 'o' },
 924                 { "notruncate", no_argument,       NULL, 'u' },
 925                 { "version",    no_argument,       NULL, 'V' },
 926                 { "noheadings", no_argument,       NULL, 'n' },
 927                 { "nowrap",     no_argument,       NULL, 'W' },
 928                 { "list",       no_argument,       NULL, 'l' },
 929                 { "raw",        no_argument,       NULL, 'r' },
 930                 { "type",       required_argument, NULL, 't' },
 931                 { NULL, 0, NULL, 0 }
 932         };
 933
 934         static const ul_excl_t excl[] = {       /* rows and cols in ASCII order */
 935                 { 'J','r' },
 936                 { 0 }
 937         };
 938         int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
 939         int enabling_netnsid = 0;
 940
 941         setlocale(LC_ALL, "");
 942         bindtextdomain(PACKAGE, LOCALEDIR);
 943         textdomain(PACKAGE);
 944         atexit(close_stdout);
 945
 946         lsns_init_debug();
 947         memset(&ls, 0, sizeof(ls));
 948
 949         INIT_LIST_HEAD(&ls.processes);
 950         INIT_LIST_HEAD(&ls.namespaces);
 951         INIT_LIST_HEAD(&netnsids_cache);
 952
 953         while ((c = getopt_long(argc, argv,
 954                                 "Jlp:o:nruhVt:W", long_opts, NULL)) != -1) {
 955
 956                 err_exclusive_options(c, long_opts, excl, excl_st);
 957
 958                 switch(c) {
 959                 case 'J':
 960                         ls.json = 1;
 961                         break;
 962                 case 'l':
 963                         ls.list = 1;
 964                         break;
 965                 case 'o':
 966                         outarg = optarg;
 967                         break;
 968                 case 'V':
 969                         printf(UTIL_LINUX_VERSION);
 970                         return EXIT_SUCCESS;
 971                 case 'p':
 972                         ls.fltr_pid = strtos32_or_err(optarg, _("invalid PID argument"));
 973                         break;
 974                 case 'h':
 975                         usage();
 976                 case 'n':
 977                         ls.no_headings = 1;
 978                         break;
 979                 case 'r':
 980                         ls.no_wrap = ls.raw = 1;
 981                         break;
 982                 case 'u':
 983                         ls.no_trunc = 1;
 984                         break;
 985                 case 't':
 986                 {
 987                         int type = ns_name2type(optarg);
 988                         if (type < 0)
 989                                 errx(EXIT_FAILURE, _("unknown namespace type: %s"), optarg);
 990                         ls.fltr_types[type] = 1;
 991                         ls.fltr_ntypes++;
 992                         if (type == LSNS_ID_NET)
 993                                 enabling_netnsid = 1;
 994                         break;
 995                 }
 996                 case 'W':
 997                         ls.no_wrap = 1;
 998                         break;
 999                 default:
1000                         errtryhelp(EXIT_FAILURE);
1001                 }
1002         }
1003
1004         if (!ls.fltr_ntypes) {
1005                 size_t i;
1006
1007                 for (i = 0; i < ARRAY_SIZE(ns_names); i++)
1008                         ls.fltr_types[i] = 1;
1009         }
1010
1011         if (optind < argc) {
1012                 if (ls.fltr_pid)
1013                         errx(EXIT_FAILURE, _("--task is mutually exclusive with <namespace>"));
1014                 ls.fltr_ns = strtou64_or_err(argv[optind], _("invalid namespace argument"));
1015                 ls.tree = ls.list ? 0 : 1;
1016
1017                 if (!ncolumns) {
1018                         columns[ncolumns++] = COL_PID;
1019                         columns[ncolumns++] = COL_PPID;
1020                         columns[ncolumns++] = COL_USER;
1021                         columns[ncolumns++] = COL_COMMAND;
1022                 }
1023         }
1024
1025         if (!ncolumns) {
1026                 columns[ncolumns++] = COL_NS;
1027                 columns[ncolumns++] = COL_TYPE;
1028                 columns[ncolumns++] = COL_NPROCS;
1029                 columns[ncolumns++] = COL_PID;
1030                 columns[ncolumns++] = COL_USER;
1031                 if (enabling_netnsid) {
1032                         columns[ncolumns++] = COL_NETNSID;
1033                         columns[ncolumns++] = COL_NSFS;
1034                 }
1035                 columns[ncolumns++] = COL_COMMAND;
1036         }
1037
1038         if (outarg) {
1039                 size_t i;
1040
1041                 if (string_add_to_idarray(outarg, columns, ARRAY_SIZE(columns),
1042                                           &ncolumns, column_name_to_id) < 0)
1043                         return EXIT_FAILURE;
1044
1045                 for (i = 0; i < ncolumns; i++) {
1046                         if (columns[i] == COL_NETNSID) {
1047                                 enabling_netnsid = 1;
1048                                 break;
1049                         }
1050                 }
1051         }
1052         scols_init_debug(0);
1053
1054         uid_cache = new_idcache();
1055         if (!uid_cache)
1056                 err(EXIT_FAILURE, _("failed to allocate UID cache"));
1057
1058 #ifdef HAVE_LINUX_NET_NAMESPACE_H
1059         if (enabling_netnsid)
1060                 netlink_fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
1061 #endif
1062         ls.tab = mnt_new_table_from_file(_PATH_PROC_MOUNTINFO);
1063         if (!ls.tab)
1064                 err(MNT_EX_FAIL, _("failed to parse %s"), _PATH_PROC_MOUNTINFO);
1065
1066         r = read_processes(&ls);
1067         if (!r)
1068                 r = read_namespaces(&ls);
1069         if (!r) {
1070                 if (ls.fltr_ns) {
1071                         struct lsns_namespace *ns = get_namespace(&ls, ls.fltr_ns);
1072
1073                         if (!ns)
1074                                 errx(EXIT_FAILURE, _("not found namespace: %ju"), (uintmax_t) ls.fltr_ns);
1075                         r = show_namespace_processes(&ls, ns);
1076                 } else
1077                         r = show_namespaces(&ls);
1078         }
1079
1080         mnt_free_table(ls.tab);
1081         if (netlink_fd >= 0)
1082                 close(netlink_fd);
1083         free_idcache(uid_cache);
1084         return r == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
1085 }