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 #define UL_DEBUG_CURRENT_MASK   UL_DEBUG_MASK(lsns)
  70 #include "debugobj.h"
  71
  72 static struct idcache *uid_cache = NULL;
  73
  74 /* column IDs */
  75 enum {
  76         COL_NS = 0,
  77         COL_TYPE,
  78         COL_PATH,
  79         COL_NPROCS,
  80         COL_PID,
  81         COL_PPID,
  82         COL_COMMAND,
  83         COL_UID,
  84         COL_USER,
  85         COL_NETNSID,
  86         COL_NSFS,
  87 };
  88
  89 /* column names */
  90 struct colinfo {
  91         const char *name; /* header */
  92         double     whint; /* width hint (N < 1 is in percent of termwidth) */
  93         int        flags; /* SCOLS_FL_* */
  94         const char *help;
  95 };
  96
  97 /* columns descriptions */
  98 static const struct colinfo infos[] = {
  99         [COL_NS]      = { "NS",     10, SCOLS_FL_RIGHT, N_("namespace identifier (inode number)") },
 100         [COL_TYPE]    = { "TYPE",    5, 0, N_("kind of namespace") },
 101         [COL_PATH]    = { "PATH",    0, 0, N_("path to the namespace")},
 102         [COL_NPROCS]  = { "NPROCS",  5, SCOLS_FL_RIGHT, N_("number of processes in the namespace") },
 103         [COL_PID]     = { "PID",     5, SCOLS_FL_RIGHT, N_("lowest PID in the namespace") },
 104         [COL_PPID]    = { "PPID",    5, SCOLS_FL_RIGHT, N_("PPID of the PID") },
 105         [COL_COMMAND] = { "COMMAND", 0, SCOLS_FL_TRUNC, N_("command line of the PID")},
 106         [COL_UID]     = { "UID",     0, SCOLS_FL_RIGHT, N_("UID of the PID")},
 107         [COL_USER]    = { "USER",    0, 0, N_("username of the PID")},
 108         [COL_NETNSID] = { "NETNSID", 0, SCOLS_FL_RIGHT, N_("namespace ID as used by network subsystem")},
 109         [COL_NSFS]    = { "NSFS",    0, SCOLS_FL_WRAP, N_("nsfs mountpoint (usually used network subsystem)")}
 110 };
 111
 112 static int columns[ARRAY_SIZE(infos) * 2];
 113 static size_t ncolumns;
 114
 115 enum {
 116         LSNS_ID_MNT = 0,
 117         LSNS_ID_NET,
 118         LSNS_ID_PID,
 119         LSNS_ID_UTS,
 120         LSNS_ID_IPC,
 121         LSNS_ID_USER,
 122         LSNS_ID_CGROUP
 123 };
 124
 125 static char *ns_names[] = {
 126         [LSNS_ID_MNT] = "mnt",
 127         [LSNS_ID_NET] = "net",
 128         [LSNS_ID_PID] = "pid",
 129         [LSNS_ID_UTS] = "uts",
 130         [LSNS_ID_IPC] = "ipc",
 131         [LSNS_ID_USER] = "user",
 132         [LSNS_ID_CGROUP] = "cgroup"
 133 };
 134
 135 struct lsns_namespace {
 136         ino_t id;
 137         int type;                       /* LSNS_* */
 138         int nprocs;
 139         int netnsid;
 140
 141         struct lsns_process *proc;
 142
 143         struct list_head namespaces;    /* lsns->processes member */
 144         struct list_head processes;     /* head of lsns_process *siblings */
 145 };
 146
 147 struct lsns_process {
 148         pid_t pid;              /* process PID */
 149         pid_t ppid;             /* parent's PID */
 150         pid_t tpid;             /* thread group */
 151         char state;
 152         uid_t uid;
 153
 154         ino_t            ns_ids[ARRAY_SIZE(ns_names)];
 155         struct list_head ns_siblings[ARRAY_SIZE(ns_names)];
 156
 157         struct list_head processes;     /* list of processes */
 158
 159         struct libscols_line *outline;
 160         struct lsns_process *parent;
 161
 162         int netnsid;
 163 };
 164
 165 struct lsns {
 166         struct list_head processes;
 167         struct list_head namespaces;
 168
 169         pid_t   fltr_pid;       /* filter out by PID */
 170         ino_t   fltr_ns;        /* filter out by namespace */
 171         int     fltr_types[ARRAY_SIZE(ns_names)];
 172         int     fltr_ntypes;
 173
 174         unsigned int raw        : 1,
 175                      json       : 1,
 176                      tree       : 1,
 177                      list       : 1,
 178                      no_trunc   : 1,
 179                      no_headings: 1,
 180                      no_wrap    : 1;
 181
 182         struct libmnt_table *tab;
 183 };
 184
 185 struct netnsid_cache {
 186         ino_t ino;
 187         int   id;
 188         struct list_head netnsids;
 189 };
 190
 191 static struct list_head netnsids_cache;
 192
 193 static int netlink_fd = -1;
 194
 195 static void lsns_init_debug(void)
 196 {
 197         __UL_INIT_DEBUG(lsns, LSNS_DEBUG_, 0, LSNS_DEBUG);
 198 }
 199
 200 static int ns_name2type(const char *name)
 201 {
 202         size_t i;
 203
 204         for (i = 0; i < ARRAY_SIZE(ns_names); i++) {
 205                 if (strcmp(ns_names[i], name) == 0)
 206                         return i;
 207         }
 208         return -1;
 209 }
 210
 211 static int column_name_to_id(const char *name, size_t namesz)
 212 {
 213         size_t i;
 214
 215         assert(name);
 216
 217         for (i = 0; i < ARRAY_SIZE(infos); i++) {
 218                 const char *cn = infos[i].name;
 219
 220                 if (!strncasecmp(name, cn, namesz) && !*(cn + namesz))
 221                         return i;
 222         }
 223         warnx(_("unknown column: %s"), name);
 224         return -1;
 225 }
 226
 227 static int has_column(int id)
 228 {
 229         size_t i;
 230
 231         for (i = 0; i < ncolumns; i++) {
 232                 if (columns[i] == id)
 233                         return 1;
 234         }
 235         return 0;
 236 }
 237
 238 static inline int get_column_id(int num)
 239 {
 240         assert(num >= 0);
 241         assert((size_t) num < ncolumns);
 242         assert(columns[num] < (int) ARRAY_SIZE(infos));
 243
 244         return columns[num];
 245 }
 246
 247 static inline const struct colinfo *get_column_info(unsigned num)
 248 {
 249         return &infos[ get_column_id(num) ];
 250 }
 251
 252 static int get_ns_ino(int dir, const char *nsname, ino_t *ino)
 253 {
 254         struct stat st;
 255         char path[16];
 256
 257         snprintf(path, sizeof(path), "ns/%s", nsname);
 258
 259         if (fstatat(dir, path, &st, 0) != 0)
 260                 return -errno;
 261         *ino = st.st_ino;
 262         return 0;
 263 }
 264
 265 static int parse_proc_stat(FILE *fp, pid_t *pid, char *state, pid_t *ppid)
 266 {
 267         char *line = NULL, *p;
 268         size_t len = 0;
 269         int rc;
 270
 271         if (getline(&line, &len, fp) < 0) {
 272                 rc = -errno;
 273                 goto error;
 274         }
 275
 276         p = strrchr(line, ')');
 277         if (p == NULL ||
 278             sscanf(line, "%d (", pid) != 1 ||
 279             sscanf(p, ") %c %d*[^\n]", state, ppid) != 2) {
 280                 rc = -EINVAL;
 281                 goto error;
 282         }
 283         rc = 0;
 284
 285 error:
 286         free(line);
 287         return rc;
 288 }
 289
 290 #ifdef HAVE_LINUX_NET_NAMESPACE_H
 291 static int netnsid_cache_find(ino_t netino, int *netnsid)
 292 {
 293         struct list_head *p;
 294
 295         list_for_each(p, &netnsids_cache) {
 296                 struct netnsid_cache *e = list_entry(p,
 297                                                      struct netnsid_cache,
 298                                                      netnsids);
 299                 if (e->ino == netino) {
 300                         *netnsid = e->id;
 301                         return 1;
 302                 }
 303         }
 304
 305         return 0;
 306 }
 307
 308 static void netnsid_cache_add(ino_t netino, int netnsid)
 309 {
 310         struct netnsid_cache *e;
 311
 312         e = xcalloc(1, sizeof(*e));
 313         e->ino = netino;
 314         e->id  = netnsid;
 315         INIT_LIST_HEAD(&e->netnsids);
 316         list_add(&e->netnsids, &netnsids_cache);
 317 }
 318
 319 static int get_netnsid_via_netlink_send_request(int target_fd)
 320 {
 321         unsigned char req[NLMSG_SPACE(sizeof(struct rtgenmsg))
 322                           + RTA_SPACE(sizeof(int32_t))];
 323
 324         struct nlmsghdr *nlh = (struct nlmsghdr *)req;
 325         struct rtgenmsg *rt = NLMSG_DATA(req);
 326         struct rtattr *rta = (struct rtattr *)
 327                 (req + NLMSG_SPACE(sizeof(struct rtgenmsg)));
 328         int32_t *fd = RTA_DATA(rta);
 329
 330         nlh->nlmsg_len = sizeof(req);
 331         nlh->nlmsg_flags = NLM_F_REQUEST;
 332         nlh->nlmsg_type = RTM_GETNSID;
 333         rt->rtgen_family = AF_UNSPEC;
 334         rta->rta_type = NETNSA_FD;
 335         rta->rta_len = RTA_SPACE(sizeof(int32_t));
 336         *fd = target_fd;
 337
 338         if (send(netlink_fd, req, sizeof(req), 0) < 0)
 339                 return -1;
 340         return 0;
 341 }
 342
 343 static int get_netnsid_via_netlink_recv_response(int *netnsid)
 344 {
 345         unsigned char res[NLMSG_SPACE(sizeof(struct rtgenmsg))
 346                           + ((RTA_SPACE(sizeof(int32_t))
 347                               < RTA_SPACE(sizeof(struct nlmsgerr)))
 348                              ? RTA_SPACE(sizeof(struct nlmsgerr))
 349                              : RTA_SPACE(sizeof(int32_t)))];
 350         int reslen, rtalen;
 351
 352         struct nlmsghdr *nlh;
 353         struct rtattr *rta;
 354
 355         reslen = recv(netlink_fd, res, sizeof(res), 0);
 356         if (reslen < 0)
 357                 return -1;
 358
 359         nlh = (struct nlmsghdr *)res;
 360         if (!(NLMSG_OK(nlh, reslen)
 361               && nlh->nlmsg_type == RTM_NEWNSID))
 362                 return -1;
 363
 364         rtalen = NLMSG_PAYLOAD(nlh, sizeof(struct rtgenmsg));
 365         rta = (struct rtattr *)(res + NLMSG_SPACE(sizeof(struct rtgenmsg)));
 366         if (!(RTA_OK(rta, rtalen)
 367               && rta->rta_type == NETNSA_NSID))
 368                 return -1;
 369
 370         *netnsid = *(int *)RTA_DATA(rta);
 371
 372         return 0;
 373 }
 374
 375 static int get_netnsid_via_netlink(int dir, const char *path)
 376 {
 377         int netnsid;
 378         int target_fd;
 379
 380         if (netlink_fd < 0)
 381                 return LSNS_NETNS_UNUSABLE;
 382
 383         target_fd = openat(dir, path, O_RDONLY);
 384         if (target_fd < 0)
 385                 return LSNS_NETNS_UNUSABLE;
 386
 387         if (get_netnsid_via_netlink_send_request(target_fd) < 0) {
 388                 netnsid = LSNS_NETNS_UNUSABLE;
 389                 goto out;
 390         }
 391
 392         if (get_netnsid_via_netlink_recv_response(&netnsid) < 0) {
 393                 netnsid = LSNS_NETNS_UNUSABLE;
 394                 goto out;
 395         }
 396
 397  out:
 398         close(target_fd);
 399         return netnsid;
 400 }
 401
 402 static int get_netnsid(int dir, ino_t netino)
 403 {
 404         int netnsid;
 405
 406         if (!netnsid_cache_find(netino, &netnsid)) {
 407                 netnsid = get_netnsid_via_netlink(dir, "ns/net");
 408                 netnsid_cache_add(netino, netnsid);
 409         }
 410
 411         return netnsid;
 412 }
 413 #else
 414 static int get_netnsid(int dir __attribute__((__unused__)),
 415                        ino_t netino __attribute__((__unused__)))
 416 {
 417         return LSNS_NETNS_UNUSABLE;
 418 }
 419 #endif /* HAVE_LINUX_NET_NAMESPACE_H */
 420
 421 static int read_process(struct lsns *ls, pid_t pid)
 422 {
 423         struct lsns_process *p = NULL;
 424         char buf[BUFSIZ];
 425         DIR *dir;
 426         int rc = 0, fd;
 427         FILE *f = NULL;
 428         size_t i;
 429         struct stat st;
 430
 431         DBG(PROC, ul_debug("reading %d", (int) pid));
 432
 433         snprintf(buf, sizeof(buf), "/proc/%d", pid);
 434         dir = opendir(buf);
 435         if (!dir)
 436                 return -errno;
 437
 438         p = xcalloc(1, sizeof(*p));
 439         if (!p) {
 440                 rc = -ENOMEM;
 441                 goto done;
 442         }
 443         p->netnsid = LSNS_NETNS_UNUSABLE;
 444
 445         if (fstat(dirfd(dir), &st) == 0) {
 446                 p->uid = st.st_uid;
 447                 add_uid(uid_cache, st.st_uid);
 448         }
 449
 450         fd = openat(dirfd(dir), "stat", O_RDONLY);
 451         if (fd < 0) {
 452                 rc = -errno;
 453                 goto done;
 454         }
 455         if (!(f = fdopen(fd, "r"))) {
 456                 rc = -errno;
 457                 goto done;
 458         }
 459         rc = parse_proc_stat(f, &p->pid, &p->state, &p->ppid);
 460         if (rc < 0)
 461                 goto done;
 462         rc = 0;
 463
 464         for (i = 0; i < ARRAY_SIZE(p->ns_ids); i++) {
 465                 INIT_LIST_HEAD(&p->ns_siblings[i]);
 466
 467                 if (!ls->fltr_types[i])
 468                         continue;
 469
 470                 rc = get_ns_ino(dirfd(dir), ns_names[i], &p->ns_ids[i]);
 471                 if (rc && rc != -EACCES && rc != -ENOENT)
 472                         goto done;
 473                 if (i == LSNS_ID_NET)
 474                         p->netnsid = get_netnsid(dirfd(dir), p->ns_ids[i]);
 475                 rc = 0;
 476         }
 477
 478         INIT_LIST_HEAD(&p->processes);
 479
 480         DBG(PROC, ul_debugobj(p, "new pid=%d", p->pid));
 481         list_add_tail(&p->processes, &ls->processes);
 482 done:
 483         if (f)
 484                 fclose(f);
 485         closedir(dir);
 486         if (rc)
 487                 free(p);
 488         return rc;
 489 }
 490
 491 static int read_processes(struct lsns *ls)
 492 {
 493         struct proc_processes *proc = NULL;
 494         pid_t pid;
 495         int rc = 0;
 496
 497         DBG(PROC, ul_debug("opening /proc"));
 498
 499         if (!(proc = proc_open_processes())) {
 500                 rc = -errno;
 501                 goto done;
 502         }
 503
 504         while (proc_next_pid(proc, &pid) == 0) {
 505                 rc = read_process(ls, pid);
 506                 if (rc && rc != -EACCES && rc != -ENOENT)
 507                         break;
 508                 rc = 0;
 509         }
 510 done:
 511         DBG(PROC, ul_debug("closing /proc"));
 512         proc_close_processes(proc);
 513         return rc;
 514 }
 515
 516 static struct lsns_namespace *get_namespace(struct lsns *ls, ino_t ino)
 517 {
 518         struct list_head *p;
 519
 520         list_for_each(p, &ls->namespaces) {
 521                 struct lsns_namespace *ns = list_entry(p, struct lsns_namespace, namespaces);
 522
 523                 if (ns->id == ino)
 524                         return ns;
 525         }
 526         return NULL;
 527 }
 528
 529 static int namespace_has_process(struct lsns_namespace *ns, pid_t pid)
 530 {
 531         struct list_head *p;
 532
 533         list_for_each(p, &ns->processes) {
 534                 struct lsns_process *proc = list_entry(p, struct lsns_process, ns_siblings[ns->type]);
 535
 536                 if (proc->pid == pid)
 537                         return 1;
 538         }
 539         return 0;
 540 }
 541
 542 static struct lsns_namespace *add_namespace(struct lsns *ls, int type, ino_t ino)
 543 {
 544         struct lsns_namespace *ns = xcalloc(1, sizeof(*ns));
 545
 546         if (!ns)
 547                 return NULL;
 548
 549         DBG(NS, ul_debugobj(ns, "new %s[%ju]", ns_names[type], (uintmax_t)ino));
 550
 551         INIT_LIST_HEAD(&ns->processes);
 552         INIT_LIST_HEAD(&ns->namespaces);
 553
 554         ns->type = type;
 555         ns->id = ino;
 556
 557         list_add_tail(&ns->namespaces, &ls->namespaces);
 558         return ns;
 559 }
 560
 561 static int add_process_to_namespace(struct lsns *ls, struct lsns_namespace *ns, struct lsns_process *proc)
 562 {
 563         struct list_head *p;
 564
 565         DBG(NS, ul_debugobj(ns, "add process [%p] pid=%d to %s[%ju]",
 566                 proc, proc->pid, ns_names[ns->type], (uintmax_t)ns->id));
 567
 568         list_for_each(p, &ls->processes) {
 569                 struct lsns_process *xproc = list_entry(p, struct lsns_process, processes);
 570
 571                 if (xproc->pid == proc->ppid)           /* my parent */
 572                         proc->parent = xproc;
 573                 else if (xproc->ppid == proc->pid)      /* my child */
 574                         xproc->parent = proc;
 575         }
 576
 577         list_add_tail(&proc->ns_siblings[ns->type], &ns->processes);
 578         ns->nprocs++;
 579
 580         if (!ns->proc || ns->proc->pid > proc->pid)
 581                 ns->proc = proc;
 582
 583         return 0;
 584 }
 585
 586 static int cmp_namespaces(struct list_head *a, struct list_head *b,
 587                           __attribute__((__unused__)) void *data)
 588 {
 589         struct lsns_namespace *xa = list_entry(a, struct lsns_namespace, namespaces),
 590                               *xb = list_entry(b, struct lsns_namespace, namespaces);
 591
 592         return cmp_numbers(xa->id, xb->id);
 593 }
 594
 595 static int netnsid_xasputs(char **str, int netnsid)
 596 {
 597         if (netnsid >= 0)
 598                 return xasprintf(str, "%d", netnsid);
 599 #ifdef NETNSA_NSID_NOT_ASSIGNED
 600         else if (netnsid == NETNSA_NSID_NOT_ASSIGNED)
 601                 return xasprintf(str, "%s", "unassigned");
 602 #endif
 603         else
 604                 return 0;
 605 }
 606
 607 static int read_namespaces(struct lsns *ls)
 608 {
 609         struct list_head *p;
 610
 611         DBG(NS, ul_debug("reading namespace"));
 612
 613         list_for_each(p, &ls->processes) {
 614                 size_t i;
 615                 struct lsns_namespace *ns;
 616                 struct lsns_process *proc = list_entry(p, struct lsns_process, processes);
 617
 618                 for (i = 0; i < ARRAY_SIZE(proc->ns_ids); i++) {
 619                         if (proc->ns_ids[i] == 0)
 620                                 continue;
 621                         if (!(ns = get_namespace(ls, proc->ns_ids[i]))) {
 622                                 ns = add_namespace(ls, i, proc->ns_ids[i]);
 623                                 if (!ns)
 624                                         return -ENOMEM;
 625                         }
 626                         add_process_to_namespace(ls, ns, proc);
 627                 }
 628         }
 629
 630         list_sort(&ls->namespaces, cmp_namespaces, NULL);
 631
 632         return 0;
 633 }
 634
 635 static int is_nsfs_root(struct libmnt_fs *fs, void *data)
 636 {
 637         if (!mnt_fs_match_fstype(fs, "nsfs") || !mnt_fs_get_root(fs))
 638                 return 0;
 639
 640         return (strcmp(mnt_fs_get_root(fs), (char *)data) == 0);
 641 }
 642
 643 static int is_path_included(const char *path_set, const char *elt,
 644                               const char sep)
 645 {
 646         size_t elt_len;
 647         size_t path_set_len;
 648         char *tmp;
 649
 650
 651         tmp = strstr(path_set, elt);
 652         if (!tmp)
 653                 return 0;
 654
 655         elt_len = strlen(elt);
 656         path_set_len = strlen(path_set);
 657
 658         /* path_set includes only elt or
 659          * path_set includes elt as the first element.
 660          */
 661         if (tmp == path_set
 662             && ((path_set_len == elt_len)
 663                 || (path_set[elt_len] == sep)))
 664                 return 1;
 665
 666         /* path_set includes elt at the middle
 667          * or as the last element.
 668          */
 669         if ((*(tmp - 1) == sep)
 670             && ((*(tmp + elt_len) == sep)
 671                 || (*(tmp + elt_len) == '\0')))
 672                 return 1;
 673
 674         return 0;
 675 }
 676
 677 static int nsfs_xasputs(char **str,
 678                         struct lsns_namespace *ns,
 679                         struct libmnt_table *tab,
 680                         char sep)
 681 {
 682         struct libmnt_iter *itr = mnt_new_iter(MNT_ITER_FORWARD);
 683         char *expected_root;
 684         struct libmnt_fs *fs = NULL;
 685
 686         xasprintf(&expected_root, "%s:[%ju]", ns_names[ns->type], (uintmax_t)ns->id);
 687         *str = NULL;
 688
 689         while (mnt_table_find_next_fs(tab, itr, is_nsfs_root,
 690                                       expected_root, &fs) == 0) {
 691
 692                 const char *tgt = mnt_fs_get_target(fs);
 693
 694                 if (!*str)
 695                         xasprintf(str, "%s", tgt);
 696
 697                 else if (!is_path_included(*str, tgt, sep)) {
 698                         char *tmp = NULL;
 699
 700                         xasprintf(&tmp, "%s%c%s", *str, sep, tgt);
 701                         free(*str);
 702                         *str = tmp;
 703                 }
 704         }
 705         free(expected_root);
 706         mnt_free_iter(itr);
 707
 708         return 1;
 709 }
 710 static void add_scols_line(struct lsns *ls, struct libscols_table *table,
 711                            struct lsns_namespace *ns, struct lsns_process *proc)
 712 {
 713         size_t i;
 714         struct libscols_line *line;
 715
 716         assert(ns);
 717         assert(table);
 718
 719         line = scols_table_new_line(table,
 720                         ls->tree && proc->parent ? proc->parent->outline : NULL);
 721         if (!line) {
 722                 warn(_("failed to add line to output"));
 723                 return;
 724         }
 725
 726         for (i = 0; i < ncolumns; i++) {
 727                 char *str = NULL;
 728
 729                 switch (get_column_id(i)) {
 730                 case COL_NS:
 731                         xasprintf(&str, "%ju", (uintmax_t)ns->id);
 732                         break;
 733                 case COL_PID:
 734                         xasprintf(&str, "%d", (int) proc->pid);
 735                         break;
 736                 case COL_PPID:
 737                         xasprintf(&str, "%d", (int) proc->ppid);
 738                         break;
 739                 case COL_TYPE:
 740                         xasprintf(&str, "%s", ns_names[ns->type]);
 741                         break;
 742                 case COL_NPROCS:
 743                         xasprintf(&str, "%d", ns->nprocs);
 744                         break;
 745                 case COL_COMMAND:
 746                         str = proc_get_command(proc->pid);
 747                         if (!str)
 748                                 str = proc_get_command_name(proc->pid);
 749                         break;
 750                 case COL_PATH:
 751                         xasprintf(&str, "/proc/%d/ns/%s", (int) proc->pid, ns_names[ns->type]);
 752                         break;
 753                 case COL_UID:
 754                         xasprintf(&str, "%d", (int) proc->uid);
 755                         break;
 756                 case COL_USER:
 757                         xasprintf(&str, "%s", get_id(uid_cache, proc->uid)->name);
 758                         break;
 759                 case COL_NETNSID:
 760                         if (ns->type == LSNS_ID_NET)
 761                                 netnsid_xasputs(&str, proc->netnsid);
 762                         break;
 763                 case COL_NSFS:
 764                         nsfs_xasputs(&str, ns, ls->tab, ls->no_wrap ? ',' : '\n');
 765                         break;
 766                 default:
 767                         break;
 768                 }
 769
 770                 if (str && scols_line_refer_data(line, i, str) != 0)
 771                         err_oom();
 772         }
 773
 774         proc->outline = line;
 775 }
 776
 777 static struct libscols_table *init_scols_table(struct lsns *ls)
 778 {
 779         struct libscols_table *tab;
 780         size_t i;
 781
 782         tab = scols_new_table();
 783         if (!tab) {
 784                 warn(_("failed to initialize output table"));
 785                 return NULL;
 786         }
 787
 788         scols_table_enable_raw(tab, ls->raw);
 789         scols_table_enable_json(tab, ls->json);
 790         scols_table_enable_noheadings(tab, ls->no_headings);
 791
 792         if (ls->json)
 793                 scols_table_set_name(tab, "namespaces");
 794
 795         for (i = 0; i < ncolumns; i++) {
 796                 const struct colinfo *col = get_column_info(i);
 797                 int flags = col->flags;
 798                 struct libscols_column *cl;
 799
 800                 if (ls->no_trunc)
 801                        flags &= ~SCOLS_FL_TRUNC;
 802                 if (ls->tree && get_column_id(i) == COL_COMMAND)
 803                         flags |= SCOLS_FL_TREE;
 804                 if (ls->no_wrap)
 805                         flags &= ~SCOLS_FL_WRAP;
 806
 807                 cl = scols_table_new_column(tab, col->name, col->whint, flags);
 808                 if (cl == NULL) {
 809                         warnx(_("failed to initialize output column"));
 810                         goto err;
 811                 }
 812                 if (!ls->no_wrap && get_column_id(i) == COL_NSFS) {
 813                         scols_column_set_wrapfunc(cl,
 814                                                   scols_wrapnl_chunksize,
 815                                                   scols_wrapnl_nextchunk,
 816                                                   NULL);
 817                         scols_column_set_safechars(cl, "\n");
 818                 }
 819         }
 820
 821         return tab;
 822 err:
 823         scols_unref_table(tab);
 824         return NULL;
 825 }
 826
 827 static int show_namespaces(struct lsns *ls)
 828 {
 829         struct libscols_table *tab;
 830         struct list_head *p;
 831         int rc = 0;
 832
 833         tab = init_scols_table(ls);
 834         if (!tab)
 835                 return -ENOMEM;
 836
 837         list_for_each(p, &ls->namespaces) {
 838                 struct lsns_namespace *ns = list_entry(p, struct lsns_namespace, namespaces);
 839
 840                 if (ls->fltr_pid != 0 && !namespace_has_process(ns, ls->fltr_pid))
 841                         continue;
 842
 843                 add_scols_line(ls, tab, ns, ns->proc);
 844         }
 845
 846         scols_print_table(tab);
 847         scols_unref_table(tab);
 848         return rc;
 849 }
 850
 851 static void show_process(struct lsns *ls, struct libscols_table *tab,
 852                          struct lsns_process *proc, struct lsns_namespace *ns)
 853 {
 854         /*
 855          * create a tree from parent->child relation, but only if the parent is
 856          * within the same namespace
 857          */
 858         if (ls->tree
 859             && proc->parent
 860             && !proc->parent->outline
 861             && proc->parent->ns_ids[ns->type] == proc->ns_ids[ns->type])
 862                 show_process(ls, tab, proc->parent, ns);
 863
 864         add_scols_line(ls, tab, ns, proc);
 865 }
 866
 867
 868 static int show_namespace_processes(struct lsns *ls, struct lsns_namespace *ns)
 869 {
 870         struct libscols_table *tab;
 871         struct list_head *p;
 872
 873         tab = init_scols_table(ls);
 874         if (!tab)
 875                 return -ENOMEM;
 876
 877         list_for_each(p, &ns->processes) {
 878                 struct lsns_process *proc = list_entry(p, struct lsns_process, ns_siblings[ns->type]);
 879
 880                 if (!proc->outline)
 881                         show_process(ls, tab, proc, ns);
 882         }
 883
 884
 885         scols_print_table(tab);
 886         scols_unref_table(tab);
 887         return 0;
 888 }
 889
 890 static void __attribute__((__noreturn__)) usage(void)
 891 {
 892         FILE *out = stdout;
 893         size_t i;
 894
 895         fputs(USAGE_HEADER, out);
 896
 897         fprintf(out,
 898                 _(" %s [options] [<namespace>]\n"), program_invocation_short_name);
 899
 900         fputs(USAGE_SEPARATOR, out);
 901         fputs(_("List system namespaces.\n"), out);
 902
 903         fputs(USAGE_OPTIONS, out);
 904         fputs(_(" -J, --json             use JSON output format\n"), out);
 905         fputs(_(" -l, --list             use list format output\n"), out);
 906         fputs(_(" -n, --noheadings       don't print headings\n"), out);
 907         fputs(_(" -o, --output <list>    define which output columns to use\n"), out);
 908         fputs(_(" -p, --task <pid>       print process namespaces\n"), out);
 909         fputs(_(" -r, --raw              use the raw output format\n"), out);
 910         fputs(_(" -u, --notruncate       don't truncate text in columns\n"), out);
 911         fputs(_(" -W, --nowrap           don't use multi-line representation\n"), out);
 912         fputs(_(" -t, --type <name>      namespace type (mnt, net, ipc, user, pid, uts, cgroup)\n"), out);
 913
 914         fputs(USAGE_SEPARATOR, out);
 915         printf(USAGE_HELP_OPTIONS(24));
 916
 917         fputs(USAGE_COLUMNS, out);
 918         for (i = 0; i < ARRAY_SIZE(infos); i++)
 919                 fprintf(out, " %11s  %s\n", infos[i].name, _(infos[i].help));
 920
 921         printf(USAGE_MAN_TAIL("lsns(8)"));
 922
 923         exit(EXIT_SUCCESS);
 924 }
 925
 926
 927 int main(int argc, char *argv[])
 928 {
 929         struct lsns ls;
 930         int c;
 931         int r = 0;
 932         char *outarg = NULL;
 933         static const struct option long_opts[] = {
 934                 { "json",       no_argument,       NULL, 'J' },
 935                 { "task",       required_argument, NULL, 'p' },
 936                 { "help",       no_argument,       NULL, 'h' },
 937                 { "output",     required_argument, NULL, 'o' },
 938                 { "notruncate", no_argument,       NULL, 'u' },
 939                 { "version",    no_argument,       NULL, 'V' },
 940                 { "noheadings", no_argument,       NULL, 'n' },
 941                 { "nowrap",     no_argument,       NULL, 'W' },
 942                 { "list",       no_argument,       NULL, 'l' },
 943                 { "raw",        no_argument,       NULL, 'r' },
 944                 { "type",       required_argument, NULL, 't' },
 945                 { NULL, 0, NULL, 0 }
 946         };
 947
 948         static const ul_excl_t excl[] = {       /* rows and cols in ASCII order */
 949                 { 'J','r' },
 950                 { 0 }
 951         };
 952         int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
 953         int is_net = 0;
 954
 955         setlocale(LC_ALL, "");
 956         bindtextdomain(PACKAGE, LOCALEDIR);
 957         textdomain(PACKAGE);
 958         atexit(close_stdout);
 959
 960         lsns_init_debug();
 961         memset(&ls, 0, sizeof(ls));
 962
 963         INIT_LIST_HEAD(&ls.processes);
 964         INIT_LIST_HEAD(&ls.namespaces);
 965         INIT_LIST_HEAD(&netnsids_cache);
 966
 967         while ((c = getopt_long(argc, argv,
 968                                 "Jlp:o:nruhVt:W", long_opts, NULL)) != -1) {
 969
 970                 err_exclusive_options(c, long_opts, excl, excl_st);
 971
 972                 switch(c) {
 973                 case 'J':
 974                         ls.json = 1;
 975                         break;
 976                 case 'l':
 977                         ls.list = 1;
 978                         break;
 979                 case 'o':
 980                         outarg = optarg;
 981                         break;
 982                 case 'V':
 983                         printf(UTIL_LINUX_VERSION);
 984                         return EXIT_SUCCESS;
 985                 case 'p':
 986                         ls.fltr_pid = strtos32_or_err(optarg, _("invalid PID argument"));
 987                         break;
 988                 case 'h':
 989                         usage();
 990                 case 'n':
 991                         ls.no_headings = 1;
 992                         break;
 993                 case 'r':
 994                         ls.no_wrap = ls.raw = 1;
 995                         break;
 996                 case 'u':
 997                         ls.no_trunc = 1;
 998                         break;
 999                 case 't':
1000                 {
1001                         int type = ns_name2type(optarg);
1002                         if (type < 0)
1003                                 errx(EXIT_FAILURE, _("unknown namespace type: %s"), optarg);
1004                         ls.fltr_types[type] = 1;
1005                         ls.fltr_ntypes++;
1006                         if (type == LSNS_ID_NET)
1007                                 is_net = 1;
1008                         break;
1009                 }
1010                 case 'W':
1011                         ls.no_wrap = 1;
1012                         break;
1013                 default:
1014                         errtryhelp(EXIT_FAILURE);
1015                 }
1016         }
1017
1018         if (!ls.fltr_ntypes) {
1019                 size_t i;
1020
1021                 for (i = 0; i < ARRAY_SIZE(ns_names); i++)
1022                         ls.fltr_types[i] = 1;
1023         }
1024
1025         if (optind < argc) {
1026                 if (ls.fltr_pid)
1027                         errx(EXIT_FAILURE, _("--task is mutually exclusive with <namespace>"));
1028                 ls.fltr_ns = strtou64_or_err(argv[optind], _("invalid namespace argument"));
1029                 ls.tree = ls.list ? 0 : 1;
1030
1031                 if (!ncolumns) {
1032                         columns[ncolumns++] = COL_PID;
1033                         columns[ncolumns++] = COL_PPID;
1034                         columns[ncolumns++] = COL_USER;
1035                         columns[ncolumns++] = COL_COMMAND;
1036                 }
1037         }
1038
1039         if (!ncolumns) {
1040                 columns[ncolumns++] = COL_NS;
1041                 columns[ncolumns++] = COL_TYPE;
1042                 columns[ncolumns++] = COL_NPROCS;
1043                 columns[ncolumns++] = COL_PID;
1044                 columns[ncolumns++] = COL_USER;
1045                 if (is_net) {
1046                         columns[ncolumns++] = COL_NETNSID;
1047                         columns[ncolumns++] = COL_NSFS;
1048                 }
1049                 columns[ncolumns++] = COL_COMMAND;
1050         }
1051
1052         if (outarg && string_add_to_idarray(outarg, columns, ARRAY_SIZE(columns),
1053                                   &ncolumns, column_name_to_id) < 0)
1054                 return EXIT_FAILURE;
1055
1056         scols_init_debug(0);
1057
1058         uid_cache = new_idcache();
1059         if (!uid_cache)
1060                 err(EXIT_FAILURE, _("failed to allocate UID cache"));
1061
1062 #ifdef HAVE_LINUX_NET_NAMESPACE_H
1063         if (has_column(COL_NETNSID))
1064                 netlink_fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
1065 #endif
1066         if (has_column(COL_NSFS)) {
1067                 ls.tab = mnt_new_table_from_file(_PATH_PROC_MOUNTINFO);
1068                 if (!ls.tab)
1069                         err(MNT_EX_FAIL, _("failed to parse %s"), _PATH_PROC_MOUNTINFO);
1070         }
1071
1072         r = read_processes(&ls);
1073         if (!r)
1074                 r = read_namespaces(&ls);
1075         if (!r) {
1076                 if (ls.fltr_ns) {
1077                         struct lsns_namespace *ns = get_namespace(&ls, ls.fltr_ns);
1078
1079                         if (!ns)
1080                                 errx(EXIT_FAILURE, _("not found namespace: %ju"), (uintmax_t) ls.fltr_ns);
1081                         r = show_namespace_processes(&ls, ns);
1082                 } else
1083                         r = show_namespaces(&ls);
1084         }
1085
1086         mnt_free_table(ls.tab);
1087         if (netlink_fd >= 0)
1088                 close(netlink_fd);
1089         free_idcache(uid_cache);
1090         return r == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
1091 }