tests/utils/testapp/gen-ns-events/gen-ns-events.cpp

   1 /*
   2  * Copyright (C) 2019 Michael Jeanson <mjeanson@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #ifndef _GNU_SOURCE
   9 #define _GNU_SOURCE
  10 #endif
  11
  12 #include "signal-helper.hpp"
  13 #include "utils.h"
  14
  15 #include <common/compat/tid.hpp>
  16 #include <common/macros.hpp>
  17
  18 #include <inttypes.h>
  19 #include <popt.h>
  20 #include <sched.h>
  21 #include <stdarg.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <sys/stat.h>
  26 #include <sys/types.h>
  27 #include <unistd.h>
  28
  29 #define LTTNG_PROC_NS_PATH_MAX 40
  30
  31 /*
  32  * The runner of this test validates that the kernel supports the
  33  * namespace for which it is invoked. However, these defines are added
  34  * to allow tests to run on systems that support a given namespace,
  35  * but that use a libc that doesn't define its associated clone flag.
  36  */
  37 #ifndef CLONE_NEWNS
  38 #define CLONE_NEWNS 0x00020000
  39 #endif
  40 #ifndef CLONE_NEWCGROUP
  41 #define CLONE_NEWCGROUP 0x02000000
  42 #endif
  43 #ifndef CLONE_NEWUTS
  44 #define CLONE_NEWUTS 0x04000000
  45 #endif
  46 #ifndef CLONE_NEWIPC
  47 #define CLONE_NEWIPC 0x08000000
  48 #endif
  49 #ifndef CLONE_NEWUSER
  50 #define CLONE_NEWUSER 0x10000000
  51 #endif
  52 #ifndef CLONE_NEWPID
  53 #define CLONE_NEWPID 0x20000000
  54 #endif
  55 #ifndef CLONE_NEWNET
  56 #define CLONE_NEWNET 0x40000000
  57 #endif
  58 #ifndef CLONE_NEWTIME
  59 #define CLONE_NEWTIME 0x00000080
  60 #endif
  61
  62 static int debug = 0;
  63 static char *ns_opt = nullptr;
  64 static char *before_unshare_wait_file_path = nullptr;
  65 static char *after_unshare_wait_file_path = nullptr;
  66 static char *after_unshare_signal_file_path = nullptr;
  67
  68 static struct poptOption opts[] = {
  69         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  70         { "debug", 'd', POPT_ARG_NONE, &debug, 0, "Enable debug output", nullptr },
  71         { "ns", 'n', POPT_ARG_STRING, &ns_opt, 0, "Namespace short identifier", nullptr },
  72         { "before",
  73           'b',
  74           POPT_ARG_STRING,
  75           &before_unshare_wait_file_path,
  76           0,
  77           "Wait for file before unshare",
  78           nullptr },
  79         { "after",
  80           'a',
  81           POPT_ARG_STRING,
  82           &after_unshare_wait_file_path,
  83           0,
  84           "Wait for file after unshare",
  85           nullptr },
  86         { "signal",
  87           's',
  88           POPT_ARG_STRING,
  89           &after_unshare_signal_file_path,
  90           0,
  91           "Create signal file after unshare",
  92           nullptr },
  93         POPT_AUTOHELP{ nullptr, 0, 0, nullptr, 0, nullptr, nullptr }
  94 };
  95
  96 static ATTR_FORMAT_PRINTF(1, 2) void debug_printf(const char *format, ...)
  97 {
  98         va_list args;
  99         va_start(args, format);
 100
 101         if (debug) {
 102                 vfprintf(stderr, format, args);
 103         }
 104
 105         va_end(args);
 106 }
 107
 108 static int get_ns_inum(const char *ns, ino_t *ns_inum)
 109 {
 110         int ret = 0;
 111         struct stat sb;
 112         char proc_ns_path[LTTNG_PROC_NS_PATH_MAX];
 113
 114         /*
 115          * /proc/thread-self was introduced in kernel v3.17
 116          */
 117         if (snprintf(proc_ns_path, LTTNG_PROC_NS_PATH_MAX, "/proc/thread-self/ns/%s", ns) >= 0) {
 118                 if (stat(proc_ns_path, &sb) == 0) {
 119                         *ns_inum = sb.st_ino;
 120                 } else {
 121                         ret = -1;
 122                 }
 123                 goto end;
 124         }
 125
 126         if (snprintf(proc_ns_path,
 127                      LTTNG_PROC_NS_PATH_MAX,
 128                      "/proc/self/task/%d/%s/net",
 129                      lttng_gettid(),
 130                      ns) >= 0) {
 131                 if (stat(proc_ns_path, &sb) == 0) {
 132                         *ns_inum = sb.st_ino;
 133                 } else {
 134                         ret = -1;
 135                 }
 136                 goto end;
 137         }
 138 end:
 139         return ret;
 140 }
 141
 142 static int do_the_needful(int ns_flag, const char *ns_str)
 143 {
 144         int ret = 0;
 145         ino_t ns1, ns2;
 146
 147         ret = get_ns_inum(ns_str, &ns1);
 148         if (ret) {
 149                 debug_printf("Failed to get ns inode number for namespace %s", ns_str);
 150                 ret = -1;
 151                 goto end;
 152         }
 153         debug_printf("Initial %s ns inode number:      %" PRIuMAX "\n", ns_str, (uintmax_t) ns1);
 154
 155         /* Wait on synchronization before unshare. */
 156         if (before_unshare_wait_file_path) {
 157                 ret = wait_on_file(before_unshare_wait_file_path);
 158                 if (ret != 0) {
 159                         goto end;
 160                 }
 161         }
 162
 163         ret = unshare(ns_flag);
 164         if (ret == -1) {
 165                 perror("Failed to unshare namespace");
 166                 goto end;
 167         }
 168
 169         ret = get_ns_inum(ns_str, &ns2);
 170         if (ret) {
 171                 debug_printf("Failed to get ns inode number for namespace %s", ns_str);
 172                 ret = -1;
 173                 goto end;
 174         }
 175         debug_printf("Post unshare %s ns inode number: %" PRIuMAX "\n", ns_str, (uintmax_t) ns2);
 176
 177         /* Signal that the unshare call is completed. */
 178         if (after_unshare_signal_file_path) {
 179                 ret = create_file(after_unshare_signal_file_path);
 180                 if (ret != 0) {
 181                         goto end;
 182                 }
 183         }
 184
 185         /* Wait on synchronization after unshare. */
 186         if (after_unshare_wait_file_path) {
 187                 ret = wait_on_file(after_unshare_wait_file_path);
 188                 if (ret != 0) {
 189                         goto end;
 190                 }
 191         }
 192
 193 end:
 194         return ret;
 195 }
 196
 197 int main(int argc, const char **argv)
 198 {
 199         int opt;
 200         int ret = EXIT_SUCCESS;
 201         poptContext pc;
 202
 203         pc = poptGetContext(nullptr, argc, argv, opts, 0);
 204         poptReadDefaultConfig(pc, 0);
 205
 206         if (argc < 2) {
 207                 poptPrintHelp(pc, stderr, 0);
 208                 ret = EXIT_FAILURE;
 209                 goto end;
 210         }
 211
 212         while ((opt = poptGetNextOpt(pc)) >= 0) {
 213                 switch (opt) {
 214                 default:
 215                         poptPrintUsage(pc, stderr, 0);
 216                         ret = EXIT_FAILURE;
 217                         goto end;
 218                 }
 219         }
 220
 221         if (opt < -1) {
 222                 /* an error occurred during option processing */
 223                 poptPrintUsage(pc, stderr, 0);
 224                 fprintf(stderr,
 225                         "%s: %s\n",
 226                         poptBadOption(pc, POPT_BADOPTION_NOALIAS),
 227                         poptStrerror(opt));
 228                 ret = EXIT_FAILURE;
 229                 goto end;
 230         }
 231
 232         if (ns_opt == nullptr) {
 233                 poptPrintUsage(pc, stderr, 0);
 234                 ret = EXIT_FAILURE;
 235                 goto end;
 236         }
 237
 238         if (set_signal_handler()) {
 239                 ret = EXIT_FAILURE;
 240                 goto end;
 241         }
 242
 243         if (strncmp(ns_opt, "cgroup", 6) == 0) {
 244                 ret = do_the_needful(CLONE_NEWCGROUP, "cgroup");
 245         } else if (strncmp(ns_opt, "ipc", 3) == 0) {
 246                 ret = do_the_needful(CLONE_NEWIPC, "ipc");
 247         } else if (strncmp(ns_opt, "mnt", 3) == 0) {
 248                 ret = do_the_needful(CLONE_NEWNS, "mnt");
 249         } else if (strncmp(ns_opt, "net", 3) == 0) {
 250                 ret = do_the_needful(CLONE_NEWNET, "net");
 251         } else if (strncmp(ns_opt, "pid", 3) == 0) {
 252                 ret = do_the_needful(CLONE_NEWPID, "pid");
 253         } else if (strncmp(ns_opt, "time", 4) == 0) {
 254                 ret = do_the_needful(CLONE_NEWTIME, "time");
 255         } else if (strncmp(ns_opt, "user", 4) == 0) {
 256                 /*
 257                  * Will always fail, requires a single threaded application,
 258                  * which can't happen with UST.
 259                  */
 260                 ret = do_the_needful(CLONE_NEWUSER, "user");
 261         } else if (strncmp(ns_opt, "uts", 3) == 0) {
 262                 ret = do_the_needful(CLONE_NEWUTS, "uts");
 263         } else {
 264                 printf("invalid ns id\n");
 265                 ret = EXIT_FAILURE;
 266                 goto end;
 267         }
 268         ret = ret ? EXIT_FAILURE : EXIT_SUCCESS;
 269 end:
 270         poptFreeContext(pc);
 271         return ret;
 272 }