diff options
Diffstat (limited to 'sys-utils/unshare.c')
| -rw-r--r-- | sys-utils/unshare.c | 75 |
1 files changed, 58 insertions, 17 deletions
diff --git a/sys-utils/unshare.c b/sys-utils/unshare.c index 9de997bdc..64ea3766f 100644 --- a/sys-utils/unshare.c +++ b/sys-utils/unshare.c @@ -24,10 +24,12 @@ #include <stdio.h> #include <stdlib.h> #include <unistd.h> +#include <getopt.h> #include "nls.h" #include "c.h" #include "closestream.h" +#include "strutils.h" #ifndef CLONE_NEWSNS # define CLONE_NEWNS 0x00020000 @@ -60,10 +62,10 @@ static void usage(int status) _(" %s [options] <program> [args...]\n"), program_invocation_short_name); fputs(USAGE_OPTIONS, out); - fputs(_(" -m, --mount unshare mounts namespace\n" - " -u, --uts unshare UTS namespace (hostname etc)\n" - " -i, --ipc unshare System V IPC namespace\n" - " -n, --net unshare network namespace\n"), out); + fputs(_(" -m, --mount [=<pid>] unshare or migrate mounts namespace\n" + " -u, --uts [=<pid>] unshare or migrate UTS namespace (hostname etc)\n" + " -i, --ipc [=<pid>] unshare or migrate System V IPC namespace\n" + " -n, --net [=<pid>] unshare or migrate network namespace\n"), out); fputs(USAGE_SEPARATOR, out); fputs(USAGE_HELP, out); @@ -76,17 +78,18 @@ static void usage(int status) int main(int argc, char *argv[]) { static const struct option longopts[] = { - { "help", no_argument, 0, 'h' }, + { "help", no_argument, 0, 'h' }, { "version", no_argument, 0, 'V'}, - { "mount", no_argument, 0, 'm' }, - { "uts", no_argument, 0, 'u' }, - { "ipc", no_argument, 0, 'i' }, - { "net", no_argument, 0, 'n' }, + { "mount", optional_argument, 0, 'm' }, + { "uts", optional_argument, 0, 'u' }, + { "ipc", optional_argument, 0, 'i' }, + { "net", optional_argument, 0, 'n' }, { NULL, 0, 0, 0 } }; + int namespaces[128]; /* /proc/#/ns/<name> file descriptors */ + size_t i, nscount = 0; /* number of used namespaces[] */ int unshare_flags = 0; - int c; setlocale(LC_MESSAGES, ""); @@ -94,7 +97,13 @@ int main(int argc, char *argv[]) textdomain(PACKAGE); atexit(close_stdout); - while((c = getopt_long(argc, argv, "hVmuin", longopts, NULL)) != -1) { + memset(namespaces, 0, sizeof(namespaces)); + + while((c = getopt_long(argc, argv, + "hVm::u::i::n::", longopts, NULL)) != -1) { + + const char *ns = NULL; + switch(c) { case 'h': usage(EXIT_SUCCESS); @@ -102,26 +111,58 @@ int main(int argc, char *argv[]) printf(UTIL_LINUX_VERSION); return EXIT_SUCCESS; case 'm': - unshare_flags |= CLONE_NEWNS; + ns = "mnt"; + if (!optarg) + unshare_flags |= CLONE_NEWNS; break; case 'u': - unshare_flags |= CLONE_NEWUTS; + ns = "uts"; + if (!optarg) + unshare_flags |= CLONE_NEWUTS; break; case 'i': - unshare_flags |= CLONE_NEWIPC; + ns = "ipc"; + if (!optarg) + unshare_flags |= CLONE_NEWIPC; break; case 'n': - unshare_flags |= CLONE_NEWNET; + ns = "net"; + if (!optarg) + unshare_flags |= CLONE_NEWNET; break; default: usage(EXIT_FAILURE); } + + if (ns && optarg) { + pid_t pid; + char path[512]; + + if (nscount >= ARRAY_SIZE(namespaces)) + err(EXIT_FAILURE, _("too many new namespaces specified")); + + if (*optarg == '=') + optarg++; + + pid = strtoul_or_err(optarg, _("failed to parse pid argument")); + + sprintf(path, "/proc/%lu/ns/%s", (unsigned long) pid, ns); + namespaces[nscount] = open(path, O_RDONLY | O_CLOEXEC); + if (namespaces[nscount] < 0) + err(EXIT_FAILURE, _("cannot open %s"), path); + nscount++; + } } - if(optind >= argc) + if (optind >= argc) usage(EXIT_FAILURE); - if(-1 == unshare(unshare_flags)) + for (i = 0; i < nscount; i++) { + if (setns(namespaces[i], 0) != 0) + err(EXIT_FAILURE, _("setns failed")); + } + + if (unshare_flags && unshare(unshare_flags) != 0) err(EXIT_FAILURE, _("unshare failed")); /* drop potential root euid/egid if we had been setuid'd */ |