mirror of
https://git.kernel.org/pub/scm/network/iproute2/iproute2.git
synced 2024-11-23 18:05:53 +08:00
8f340a0751
If rtnl_listen detects error (such as netlink socket EOF), then exit with status 2 like other iproute2 monitor commands. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
1053 lines
23 KiB
C
1053 lines
23 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#define _ATFILE_SOURCE
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#include <sys/file.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <sys/wait.h>
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#include <sys/inotify.h>
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#include <sys/mount.h>
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#include <sys/syscall.h>
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#include <stdio.h>
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#include <string.h>
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#include <sched.h>
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#include <fcntl.h>
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#include <dirent.h>
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#include <errno.h>
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#include <unistd.h>
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#include <ctype.h>
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#include <linux/limits.h>
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#include <linux/net_namespace.h>
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#include "utils.h"
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#include "list.h"
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#include "ip_common.h"
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#include "namespace.h"
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#include "json_print.h"
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static int usage(void)
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{
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fprintf(stderr,
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"Usage: ip netns list\n"
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" ip netns add NAME\n"
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" ip netns attach NAME PID\n"
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" ip netns set NAME NETNSID\n"
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" ip [-all] netns delete [NAME]\n"
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" ip netns identify [PID]\n"
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" ip netns pids NAME\n"
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" ip [-all] netns exec [NAME] cmd ...\n"
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" ip netns monitor\n"
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" ip netns list-id [target-nsid POSITIVE-INT] [nsid POSITIVE-INT]\n"
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"NETNSID := auto | POSITIVE-INT\n");
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exit(-1);
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}
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/* This socket is used to get nsid */
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static struct rtnl_handle rtnsh = { .fd = -1 };
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static int have_rtnl_getnsid = -1;
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static int saved_netns = -1;
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static struct link_filter filter;
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static int ipnetns_accept_msg(struct rtnl_ctrl_data *ctrl,
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struct nlmsghdr *n, void *arg)
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{
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struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(n);
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if (n->nlmsg_type == NLMSG_ERROR &&
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(err->error == -EOPNOTSUPP || err->error == -EINVAL))
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have_rtnl_getnsid = 0;
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else
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have_rtnl_getnsid = 1;
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return -1;
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}
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static int ipnetns_have_nsid(void)
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{
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struct {
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struct nlmsghdr n;
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struct rtgenmsg g;
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char buf[1024];
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} req = {
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.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
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.n.nlmsg_flags = NLM_F_REQUEST,
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.n.nlmsg_type = RTM_GETNSID,
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.g.rtgen_family = AF_UNSPEC,
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};
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int fd;
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if (have_rtnl_getnsid >= 0) {
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fd = open("/proc/self/ns/net", O_RDONLY);
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if (fd < 0) {
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fprintf(stderr,
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"/proc/self/ns/net: %s. Continuing anyway.\n",
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strerror(errno));
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have_rtnl_getnsid = 0;
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return 0;
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}
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addattr32(&req.n, 1024, NETNSA_FD, fd);
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if (rtnl_send(&rth, &req.n, req.n.nlmsg_len) < 0) {
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fprintf(stderr,
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"rtnl_send(RTM_GETNSID): %s. Continuing anyway.\n",
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strerror(errno));
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have_rtnl_getnsid = 0;
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close(fd);
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return 0;
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}
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if (rtnl_listen(&rth, ipnetns_accept_msg, NULL) < 0)
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exit(2);
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close(fd);
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}
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return have_rtnl_getnsid;
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}
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int get_netnsid_from_name(const char *name)
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{
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netns_nsid_socket_init();
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return netns_id_from_name(&rtnsh, name);
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}
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struct nsid_cache {
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struct hlist_node nsid_hash;
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struct hlist_node name_hash;
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int nsid;
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char name[0];
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};
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#define NSIDMAP_SIZE 128
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#define NSID_HASH_NSID(nsid) (nsid & (NSIDMAP_SIZE - 1))
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#define NSID_HASH_NAME(name) (namehash(name) & (NSIDMAP_SIZE - 1))
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static struct hlist_head nsid_head[NSIDMAP_SIZE];
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static struct hlist_head name_head[NSIDMAP_SIZE];
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static struct nsid_cache *netns_map_get_by_nsid(int nsid)
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{
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struct hlist_node *n;
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uint32_t h;
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if (nsid < 0)
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return NULL;
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h = NSID_HASH_NSID(nsid);
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hlist_for_each(n, &nsid_head[h]) {
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struct nsid_cache *c = container_of(n, struct nsid_cache,
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nsid_hash);
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if (c->nsid == nsid)
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return c;
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}
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return NULL;
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}
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char *get_name_from_nsid(int nsid)
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{
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struct nsid_cache *c;
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if (nsid < 0)
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return NULL;
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netns_nsid_socket_init();
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netns_map_init();
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c = netns_map_get_by_nsid(nsid);
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if (c)
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return c->name;
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return NULL;
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}
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static int netns_map_add(int nsid, const char *name)
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{
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struct nsid_cache *c;
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uint32_t h;
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if (netns_map_get_by_nsid(nsid) != NULL)
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return -EEXIST;
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c = malloc(sizeof(*c) + strlen(name) + 1);
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if (c == NULL) {
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perror("malloc");
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return -ENOMEM;
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}
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c->nsid = nsid;
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strcpy(c->name, name);
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h = NSID_HASH_NSID(nsid);
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hlist_add_head(&c->nsid_hash, &nsid_head[h]);
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h = NSID_HASH_NAME(name);
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hlist_add_head(&c->name_hash, &name_head[h]);
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return 0;
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}
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static void netns_map_del(struct nsid_cache *c)
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{
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hlist_del(&c->name_hash);
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hlist_del(&c->nsid_hash);
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free(c);
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}
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void netns_nsid_socket_init(void)
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{
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if (rtnsh.fd > -1 || !ipnetns_have_nsid())
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return;
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if (rtnl_open(&rtnsh, 0) < 0) {
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fprintf(stderr, "Cannot open rtnetlink\n");
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exit(1);
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}
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}
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void netns_map_init(void)
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{
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static int initialized;
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struct dirent *entry;
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DIR *dir;
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int nsid;
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if (initialized || !ipnetns_have_nsid())
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return;
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dir = opendir(NETNS_RUN_DIR);
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if (!dir)
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return;
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while ((entry = readdir(dir)) != NULL) {
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if (strcmp(entry->d_name, ".") == 0)
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continue;
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if (strcmp(entry->d_name, "..") == 0)
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continue;
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nsid = get_netnsid_from_name(entry->d_name);
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if (nsid >= 0)
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netns_map_add(nsid, entry->d_name);
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}
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closedir(dir);
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initialized = 1;
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}
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static int netns_get_name(int nsid, char *name)
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{
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struct dirent *entry;
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DIR *dir;
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int id;
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if (nsid < 0)
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return -EINVAL;
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dir = opendir(NETNS_RUN_DIR);
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if (!dir)
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return -ENOENT;
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while ((entry = readdir(dir)) != NULL) {
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if (strcmp(entry->d_name, ".") == 0)
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continue;
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if (strcmp(entry->d_name, "..") == 0)
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continue;
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id = get_netnsid_from_name(entry->d_name);
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if (id >= 0 && nsid == id) {
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strcpy(name, entry->d_name);
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closedir(dir);
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return 0;
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}
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}
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closedir(dir);
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return -ENOENT;
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}
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int print_nsid(struct nlmsghdr *n, void *arg)
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{
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struct rtgenmsg *rthdr = NLMSG_DATA(n);
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struct rtattr *tb[NETNSA_MAX+1];
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int len = n->nlmsg_len;
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FILE *fp = (FILE *)arg;
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struct nsid_cache *c;
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char name[NAME_MAX];
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int nsid, current;
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if (n->nlmsg_type != RTM_NEWNSID && n->nlmsg_type != RTM_DELNSID)
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return 0;
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len -= NLMSG_SPACE(sizeof(*rthdr));
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if (len < 0) {
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fprintf(stderr, "BUG: wrong nlmsg len %d in %s\n", len,
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__func__);
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return -1;
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}
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parse_rtattr(tb, NETNSA_MAX, NETNS_RTA(rthdr), len);
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if (tb[NETNSA_NSID] == NULL) {
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fprintf(stderr, "BUG: NETNSA_NSID is missing %s\n", __func__);
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return -1;
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}
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open_json_object(NULL);
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if (n->nlmsg_type == RTM_DELNSID)
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print_bool(PRINT_ANY, "deleted", "Deleted ", true);
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nsid = rta_getattr_s32(tb[NETNSA_NSID]);
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if (nsid < 0)
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print_string(PRINT_FP, NULL, "nsid unassigned ", NULL);
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else
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print_int(PRINT_ANY, "nsid", "nsid %d ", nsid);
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if (tb[NETNSA_CURRENT_NSID]) {
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current = rta_getattr_s32(tb[NETNSA_CURRENT_NSID]);
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if (current < 0)
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print_string(PRINT_FP, NULL,
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"current-nsid unassigned ", NULL);
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else
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print_int(PRINT_ANY, "current-nsid",
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"current-nsid %d ", current);
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}
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c = netns_map_get_by_nsid(tb[NETNSA_CURRENT_NSID] ? current : nsid);
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if (c != NULL) {
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print_string(PRINT_ANY, "name",
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"(iproute2 netns name: %s)", c->name);
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netns_map_del(c);
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}
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/* nsid might not be in cache */
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if (c == NULL && n->nlmsg_type == RTM_NEWNSID)
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if (netns_get_name(nsid, name) == 0) {
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print_string(PRINT_ANY, "name",
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"(iproute2 netns name: %s)", name);
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netns_map_add(nsid, name);
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}
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print_string(PRINT_FP, NULL, "\n", NULL);
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close_json_object();
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fflush(fp);
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return 0;
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}
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static int get_netnsid_from_netnsid(int nsid)
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{
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struct {
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struct nlmsghdr n;
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struct rtgenmsg g;
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char buf[1024];
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} req = {
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.n.nlmsg_len = NLMSG_LENGTH(NLMSG_ALIGN(sizeof(struct rtgenmsg))),
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.n.nlmsg_flags = NLM_F_REQUEST,
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.n.nlmsg_type = RTM_GETNSID,
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.g.rtgen_family = AF_UNSPEC,
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};
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struct nlmsghdr *answer;
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int err;
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netns_nsid_socket_init();
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err = addattr32(&req.n, sizeof(req), NETNSA_NSID, nsid);
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if (err)
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return err;
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if (filter.target_nsid >= 0) {
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err = addattr32(&req.n, sizeof(req), NETNSA_TARGET_NSID,
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filter.target_nsid);
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if (err)
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return err;
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}
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if (rtnl_talk(&rtnsh, &req.n, &answer) < 0)
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return -2;
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/* Validate message and parse attributes */
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if (answer->nlmsg_type == NLMSG_ERROR)
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goto err_out;
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new_json_obj(json);
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err = print_nsid(answer, stdout);
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delete_json_obj();
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err_out:
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free(answer);
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return err;
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}
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static int netns_filter_req(struct nlmsghdr *nlh, int reqlen)
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{
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int err;
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if (filter.target_nsid >= 0) {
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err = addattr32(nlh, reqlen, NETNSA_TARGET_NSID,
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filter.target_nsid);
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if (err)
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return err;
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}
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return 0;
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}
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static int netns_list_id(int argc, char **argv)
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{
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int nsid = -1;
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if (!ipnetns_have_nsid()) {
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fprintf(stderr,
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"RTM_GETNSID is not supported by the kernel.\n");
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return -ENOTSUP;
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}
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filter.target_nsid = -1;
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while (argc > 0) {
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if (strcmp(*argv, "target-nsid") == 0) {
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if (filter.target_nsid >= 0)
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duparg("target-nsid", *argv);
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NEXT_ARG();
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if (get_integer(&filter.target_nsid, *argv, 0))
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invarg("\"target-nsid\" value is invalid",
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*argv);
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else if (filter.target_nsid < 0)
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invarg("\"target-nsid\" value should be >= 0",
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argv[1]);
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} else if (strcmp(*argv, "nsid") == 0) {
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if (nsid >= 0)
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duparg("nsid", *argv);
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NEXT_ARG();
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if (get_integer(&nsid, *argv, 0))
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invarg("\"nsid\" value is invalid", *argv);
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else if (nsid < 0)
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invarg("\"nsid\" value should be >= 0",
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argv[1]);
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} else
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usage();
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argc--; argv++;
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}
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if (nsid >= 0)
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return get_netnsid_from_netnsid(nsid);
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if (rtnl_nsiddump_req_filter_fn(&rth, AF_UNSPEC,
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netns_filter_req) < 0) {
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perror("Cannot send dump request");
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exit(1);
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}
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new_json_obj(json);
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if (rtnl_dump_filter(&rth, print_nsid, stdout) < 0) {
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delete_json_obj();
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fprintf(stderr, "Dump terminated\n");
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exit(1);
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}
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delete_json_obj();
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return 0;
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}
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static int netns_list(int argc, char **argv)
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{
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struct dirent *entry;
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DIR *dir;
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int id;
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dir = opendir(NETNS_RUN_DIR);
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if (!dir)
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return 0;
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new_json_obj(json);
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while ((entry = readdir(dir)) != NULL) {
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if (strcmp(entry->d_name, ".") == 0)
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continue;
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if (strcmp(entry->d_name, "..") == 0)
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continue;
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open_json_object(NULL);
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print_string(PRINT_ANY, "name",
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"%s", entry->d_name);
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if (ipnetns_have_nsid()) {
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id = get_netnsid_from_name(entry->d_name);
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if (id >= 0)
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print_int(PRINT_ANY, "id", " (id: %d)", id);
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}
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print_string(PRINT_FP, NULL, "\n", NULL);
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close_json_object();
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}
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closedir(dir);
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delete_json_obj();
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return 0;
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}
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static int do_switch(void *arg)
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{
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char *netns = arg;
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/* we just changed namespaces. clear any vrf association
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* with prior namespace before exec'ing command
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*/
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vrf_reset();
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return netns_switch(netns);
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}
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static int on_netns_exec(char *nsname, void *arg)
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{
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char **argv = arg;
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printf("\nnetns: %s\n", nsname);
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cmd_exec(argv[0], argv, true, do_switch, nsname);
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return 0;
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}
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static int netns_exec(int argc, char **argv)
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{
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/* Setup the proper environment for apps that are not netns
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* aware, and execute a program in that environment.
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*/
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if (argc < 1 && !do_all) {
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fprintf(stderr, "No netns name specified\n");
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return -1;
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}
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if ((argc < 2 && !do_all) || (argc < 1 && do_all)) {
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fprintf(stderr, "No command specified\n");
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return -1;
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}
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if (do_all)
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return netns_foreach(on_netns_exec, argv);
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/* ip must return the status of the child,
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* but do_cmd() will add a minus to this,
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* so let's add another one here to cancel it.
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*/
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return -cmd_exec(argv[1], argv + 1, !!batch_mode, do_switch, argv[0]);
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}
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static int is_pid(const char *str)
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{
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int ch;
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for (; (ch = *str); str++) {
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if (!isdigit(ch))
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return 0;
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}
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return 1;
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}
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static int netns_pids(int argc, char **argv)
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{
|
|
const char *name;
|
|
char net_path[PATH_MAX];
|
|
int netns = -1, ret = -1;
|
|
struct stat netst;
|
|
DIR *dir;
|
|
struct dirent *entry;
|
|
|
|
if (argc < 1) {
|
|
fprintf(stderr, "No netns name specified\n");
|
|
goto out;
|
|
}
|
|
if (argc > 1) {
|
|
fprintf(stderr, "extra arguments specified\n");
|
|
goto out;
|
|
}
|
|
|
|
name = argv[0];
|
|
snprintf(net_path, sizeof(net_path), "%s/%s", NETNS_RUN_DIR, name);
|
|
netns = open(net_path, O_RDONLY);
|
|
if (netns < 0) {
|
|
fprintf(stderr, "Cannot open network namespace: %s\n",
|
|
strerror(errno));
|
|
goto out;
|
|
}
|
|
if (fstat(netns, &netst) < 0) {
|
|
fprintf(stderr, "Stat of netns failed: %s\n",
|
|
strerror(errno));
|
|
goto out;
|
|
}
|
|
dir = opendir("/proc/");
|
|
if (!dir) {
|
|
fprintf(stderr, "Open of /proc failed: %s\n",
|
|
strerror(errno));
|
|
goto out;
|
|
}
|
|
while ((entry = readdir(dir))) {
|
|
char pid_net_path[PATH_MAX];
|
|
struct stat st;
|
|
|
|
if (!is_pid(entry->d_name))
|
|
continue;
|
|
snprintf(pid_net_path, sizeof(pid_net_path), "/proc/%s/ns/net",
|
|
entry->d_name);
|
|
if (stat(pid_net_path, &st) != 0)
|
|
continue;
|
|
if ((st.st_dev == netst.st_dev) &&
|
|
(st.st_ino == netst.st_ino)) {
|
|
printf("%s\n", entry->d_name);
|
|
}
|
|
}
|
|
ret = 0;
|
|
closedir(dir);
|
|
out:
|
|
if (netns >= 0)
|
|
close(netns);
|
|
return ret;
|
|
|
|
}
|
|
|
|
int netns_identify_pid(const char *pidstr, char *name, int len)
|
|
{
|
|
char net_path[PATH_MAX];
|
|
int netns = -1, ret = -1;
|
|
struct stat netst;
|
|
DIR *dir;
|
|
struct dirent *entry;
|
|
|
|
name[0] = '\0';
|
|
|
|
snprintf(net_path, sizeof(net_path), "/proc/%s/ns/net", pidstr);
|
|
netns = open(net_path, O_RDONLY);
|
|
if (netns < 0) {
|
|
fprintf(stderr, "Cannot open network namespace: %s\n",
|
|
strerror(errno));
|
|
goto out;
|
|
}
|
|
if (fstat(netns, &netst) < 0) {
|
|
fprintf(stderr, "Stat of netns failed: %s\n",
|
|
strerror(errno));
|
|
goto out;
|
|
}
|
|
dir = opendir(NETNS_RUN_DIR);
|
|
if (!dir) {
|
|
/* Succeed treat a missing directory as an empty directory */
|
|
if (errno == ENOENT) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
fprintf(stderr, "Failed to open directory %s:%s\n",
|
|
NETNS_RUN_DIR, strerror(errno));
|
|
goto out;
|
|
}
|
|
|
|
while ((entry = readdir(dir))) {
|
|
char name_path[PATH_MAX];
|
|
struct stat st;
|
|
|
|
if (strcmp(entry->d_name, ".") == 0)
|
|
continue;
|
|
if (strcmp(entry->d_name, "..") == 0)
|
|
continue;
|
|
|
|
snprintf(name_path, sizeof(name_path), "%s/%s", NETNS_RUN_DIR,
|
|
entry->d_name);
|
|
|
|
if (stat(name_path, &st) != 0)
|
|
continue;
|
|
|
|
if ((st.st_dev == netst.st_dev) &&
|
|
(st.st_ino == netst.st_ino)) {
|
|
strlcpy(name, entry->d_name, len);
|
|
}
|
|
}
|
|
ret = 0;
|
|
closedir(dir);
|
|
out:
|
|
if (netns >= 0)
|
|
close(netns);
|
|
return ret;
|
|
|
|
}
|
|
|
|
static int netns_identify(int argc, char **argv)
|
|
{
|
|
const char *pidstr;
|
|
char name[256];
|
|
int rc;
|
|
|
|
if (argc < 1) {
|
|
pidstr = "self";
|
|
} else if (argc > 1) {
|
|
fprintf(stderr, "extra arguments specified\n");
|
|
return -1;
|
|
} else {
|
|
pidstr = argv[0];
|
|
if (!is_pid(pidstr)) {
|
|
fprintf(stderr, "Specified string '%s' is not a pid\n",
|
|
pidstr);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
rc = netns_identify_pid(pidstr, name, sizeof(name));
|
|
if (!rc)
|
|
printf("%s\n", name);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int on_netns_del(char *nsname, void *arg)
|
|
{
|
|
char netns_path[PATH_MAX];
|
|
|
|
snprintf(netns_path, sizeof(netns_path), "%s/%s", NETNS_RUN_DIR, nsname);
|
|
umount2(netns_path, MNT_DETACH);
|
|
if (unlink(netns_path) < 0) {
|
|
fprintf(stderr, "Cannot remove namespace file \"%s\": %s\n",
|
|
netns_path, strerror(errno));
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int netns_delete(int argc, char **argv)
|
|
{
|
|
if (argc < 1 && !do_all) {
|
|
fprintf(stderr, "No netns name specified\n");
|
|
return -1;
|
|
}
|
|
|
|
if (do_all)
|
|
return netns_foreach(on_netns_del, NULL);
|
|
|
|
return on_netns_del(argv[0], NULL);
|
|
}
|
|
|
|
static int create_netns_dir(void)
|
|
{
|
|
/* Create the base netns directory if it doesn't exist */
|
|
if (mkdir(NETNS_RUN_DIR, S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH)) {
|
|
if (errno != EEXIST) {
|
|
fprintf(stderr, "mkdir %s failed: %s\n",
|
|
NETNS_RUN_DIR, strerror(errno));
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Obtain a FD for the current namespace, so we can reenter it later */
|
|
static void netns_save(void)
|
|
{
|
|
if (saved_netns != -1)
|
|
return;
|
|
|
|
saved_netns = open("/proc/self/ns/net", O_RDONLY | O_CLOEXEC);
|
|
if (saved_netns == -1) {
|
|
perror("Cannot open init namespace");
|
|
exit(1);
|
|
}
|
|
}
|
|
|
|
static void netns_restore(void)
|
|
{
|
|
if (saved_netns == -1)
|
|
return;
|
|
|
|
if (setns(saved_netns, CLONE_NEWNET)) {
|
|
perror("setns");
|
|
exit(1);
|
|
}
|
|
|
|
close(saved_netns);
|
|
saved_netns = -1;
|
|
}
|
|
|
|
static int netns_add(int argc, char **argv, bool create)
|
|
{
|
|
/* This function creates a new network namespace and
|
|
* a new mount namespace and bind them into a well known
|
|
* location in the filesystem based on the name provided.
|
|
*
|
|
* If create is true, a new namespace will be created,
|
|
* otherwise an existing one will be attached to the file.
|
|
*
|
|
* The mount namespace is created so that any necessary
|
|
* userspace tweaks like remounting /sys, or bind mounting
|
|
* a new /etc/resolv.conf can be shared between users.
|
|
*/
|
|
char netns_path[PATH_MAX], proc_path[PATH_MAX];
|
|
const char *name;
|
|
pid_t pid;
|
|
int fd;
|
|
int lock;
|
|
int made_netns_run_dir_mount = 0;
|
|
|
|
if (create) {
|
|
if (argc < 1) {
|
|
fprintf(stderr, "No netns name specified\n");
|
|
return -1;
|
|
}
|
|
} else {
|
|
if (argc < 2) {
|
|
fprintf(stderr, "No netns name and PID specified\n");
|
|
return -1;
|
|
}
|
|
|
|
if (get_s32(&pid, argv[1], 0) || !pid) {
|
|
fprintf(stderr, "Invalid PID: %s\n", argv[1]);
|
|
return -1;
|
|
}
|
|
}
|
|
name = argv[0];
|
|
|
|
snprintf(netns_path, sizeof(netns_path), "%s/%s", NETNS_RUN_DIR, name);
|
|
|
|
if (create_netns_dir())
|
|
return -1;
|
|
|
|
/* Make it possible for network namespace mounts to propagate between
|
|
* mount namespaces. This makes it likely that a unmounting a network
|
|
* namespace file in one namespace will unmount the network namespace
|
|
* file in all namespaces allowing the network namespace to be freed
|
|
* sooner.
|
|
* These setup steps need to happen only once, as if multiple ip processes
|
|
* try to attempt the same operation at the same time, the mountpoints will
|
|
* be recursively created multiple times, eventually causing the system
|
|
* to lock up. For example, this has been observed when multiple netns
|
|
* namespaces are created in parallel at boot. See:
|
|
* https://bugs.debian.org/949235
|
|
* Try to take an exclusive file lock on the top level directory to ensure
|
|
* this cannot happen, but proceed nonetheless if it cannot happen for any
|
|
* reason.
|
|
*/
|
|
lock = open(NETNS_RUN_DIR, O_RDONLY|O_DIRECTORY, 0);
|
|
if (lock < 0) {
|
|
fprintf(stderr, "Cannot open netns runtime directory \"%s\": %s\n",
|
|
NETNS_RUN_DIR, strerror(errno));
|
|
return -1;
|
|
}
|
|
if (flock(lock, LOCK_EX) < 0) {
|
|
fprintf(stderr, "Warning: could not flock netns runtime directory \"%s\": %s\n",
|
|
NETNS_RUN_DIR, strerror(errno));
|
|
close(lock);
|
|
lock = -1;
|
|
}
|
|
while (mount("", NETNS_RUN_DIR, "none", MS_SHARED | MS_REC, NULL)) {
|
|
/* Fail unless we need to make the mount point */
|
|
if (errno != EINVAL || made_netns_run_dir_mount) {
|
|
fprintf(stderr, "mount --make-shared %s failed: %s\n",
|
|
NETNS_RUN_DIR, strerror(errno));
|
|
if (lock != -1) {
|
|
flock(lock, LOCK_UN);
|
|
close(lock);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/* Upgrade NETNS_RUN_DIR to a mount point */
|
|
if (mount(NETNS_RUN_DIR, NETNS_RUN_DIR, "none", MS_BIND | MS_REC, NULL)) {
|
|
fprintf(stderr, "mount --bind %s %s failed: %s\n",
|
|
NETNS_RUN_DIR, NETNS_RUN_DIR, strerror(errno));
|
|
if (lock != -1) {
|
|
flock(lock, LOCK_UN);
|
|
close(lock);
|
|
}
|
|
return -1;
|
|
}
|
|
made_netns_run_dir_mount = 1;
|
|
}
|
|
if (lock != -1) {
|
|
flock(lock, LOCK_UN);
|
|
close(lock);
|
|
}
|
|
|
|
/* Create the filesystem state */
|
|
fd = open(netns_path, O_RDONLY|O_CREAT|O_EXCL, 0);
|
|
if (fd < 0) {
|
|
fprintf(stderr, "Cannot create namespace file \"%s\": %s\n",
|
|
netns_path, strerror(errno));
|
|
return -1;
|
|
}
|
|
close(fd);
|
|
|
|
if (create) {
|
|
netns_save();
|
|
if (unshare(CLONE_NEWNET) < 0) {
|
|
fprintf(stderr, "Failed to create a new network namespace \"%s\": %s\n",
|
|
name, strerror(errno));
|
|
goto out_delete;
|
|
}
|
|
|
|
strcpy(proc_path, "/proc/self/ns/net");
|
|
} else {
|
|
snprintf(proc_path, sizeof(proc_path), "/proc/%d/ns/net", pid);
|
|
}
|
|
|
|
/* Bind the netns last so I can watch for it */
|
|
if (mount(proc_path, netns_path, "none", MS_BIND, NULL) < 0) {
|
|
fprintf(stderr, "Bind %s -> %s failed: %s\n",
|
|
proc_path, netns_path, strerror(errno));
|
|
goto out_delete;
|
|
}
|
|
netns_restore();
|
|
|
|
return 0;
|
|
out_delete:
|
|
if (create) {
|
|
netns_restore();
|
|
netns_delete(argc, argv);
|
|
} else if (unlink(netns_path) < 0) {
|
|
fprintf(stderr, "Cannot remove namespace file \"%s\": %s\n",
|
|
netns_path, strerror(errno));
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
int set_netnsid_from_name(const char *name, int nsid)
|
|
{
|
|
struct {
|
|
struct nlmsghdr n;
|
|
struct rtgenmsg g;
|
|
char buf[1024];
|
|
} req = {
|
|
.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
|
|
.n.nlmsg_flags = NLM_F_REQUEST,
|
|
.n.nlmsg_type = RTM_NEWNSID,
|
|
.g.rtgen_family = AF_UNSPEC,
|
|
};
|
|
int fd, err = 0;
|
|
|
|
netns_nsid_socket_init();
|
|
|
|
fd = netns_get_fd(name);
|
|
if (fd < 0)
|
|
return fd;
|
|
|
|
addattr32(&req.n, 1024, NETNSA_FD, fd);
|
|
addattr32(&req.n, 1024, NETNSA_NSID, nsid);
|
|
if (rtnl_talk(&rth, &req.n, NULL) < 0)
|
|
err = -2;
|
|
|
|
close(fd);
|
|
return err;
|
|
}
|
|
|
|
static int netns_set(int argc, char **argv)
|
|
{
|
|
const char *name;
|
|
int nsid;
|
|
|
|
if (argc < 1) {
|
|
fprintf(stderr, "No netns name specified\n");
|
|
return -1;
|
|
}
|
|
if (argc < 2) {
|
|
fprintf(stderr, "No nsid specified\n");
|
|
return -1;
|
|
}
|
|
name = argv[0];
|
|
/* If a negative nsid is specified the kernel will select the nsid. */
|
|
if (strcmp(argv[1], "auto") == 0)
|
|
nsid = -1;
|
|
else if (get_integer(&nsid, argv[1], 0))
|
|
invarg("Invalid \"netnsid\" value", argv[1]);
|
|
else if (nsid < 0)
|
|
invarg("\"netnsid\" value should be >= 0", argv[1]);
|
|
|
|
return set_netnsid_from_name(name, nsid);
|
|
}
|
|
|
|
static int netns_monitor(int argc, char **argv)
|
|
{
|
|
char buf[4096];
|
|
struct inotify_event *event;
|
|
int fd;
|
|
|
|
fd = inotify_init();
|
|
if (fd < 0) {
|
|
fprintf(stderr, "inotify_init failed: %s\n",
|
|
strerror(errno));
|
|
return -1;
|
|
}
|
|
|
|
if (create_netns_dir())
|
|
return -1;
|
|
|
|
if (inotify_add_watch(fd, NETNS_RUN_DIR, IN_CREATE | IN_DELETE) < 0) {
|
|
fprintf(stderr, "inotify_add_watch failed: %s\n",
|
|
strerror(errno));
|
|
return -1;
|
|
}
|
|
for (;;) {
|
|
ssize_t len = read(fd, buf, sizeof(buf));
|
|
|
|
if (len < 0) {
|
|
fprintf(stderr, "read failed: %s\n",
|
|
strerror(errno));
|
|
return -1;
|
|
}
|
|
for (event = (struct inotify_event *)buf;
|
|
(char *)event < &buf[len];
|
|
event = (struct inotify_event *)((char *)event + sizeof(*event) + event->len)) {
|
|
if (event->mask & IN_CREATE)
|
|
printf("add %s\n", event->name);
|
|
if (event->mask & IN_DELETE)
|
|
printf("delete %s\n", event->name);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int invalid_name(const char *name)
|
|
{
|
|
return !*name || strlen(name) > NAME_MAX ||
|
|
strchr(name, '/') || !strcmp(name, ".") || !strcmp(name, "..");
|
|
}
|
|
|
|
int do_netns(int argc, char **argv)
|
|
{
|
|
netns_nsid_socket_init();
|
|
|
|
if (argc < 1) {
|
|
netns_map_init();
|
|
return netns_list(0, NULL);
|
|
}
|
|
|
|
if (!do_all && argc > 1 && invalid_name(argv[1])) {
|
|
fprintf(stderr, "Invalid netns name \"%s\"\n", argv[1]);
|
|
exit(-1);
|
|
}
|
|
|
|
if ((matches(*argv, "list") == 0) || (matches(*argv, "show") == 0) ||
|
|
(matches(*argv, "lst") == 0)) {
|
|
netns_map_init();
|
|
return netns_list(argc-1, argv+1);
|
|
}
|
|
|
|
if ((matches(*argv, "list-id") == 0)) {
|
|
netns_map_init();
|
|
return netns_list_id(argc-1, argv+1);
|
|
}
|
|
|
|
if (matches(*argv, "help") == 0)
|
|
return usage();
|
|
|
|
if (matches(*argv, "add") == 0)
|
|
return netns_add(argc-1, argv+1, true);
|
|
|
|
if (matches(*argv, "set") == 0)
|
|
return netns_set(argc-1, argv+1);
|
|
|
|
if (matches(*argv, "delete") == 0)
|
|
return netns_delete(argc-1, argv+1);
|
|
|
|
if (matches(*argv, "identify") == 0)
|
|
return netns_identify(argc-1, argv+1);
|
|
|
|
if (matches(*argv, "pids") == 0)
|
|
return netns_pids(argc-1, argv+1);
|
|
|
|
if (matches(*argv, "exec") == 0)
|
|
return netns_exec(argc-1, argv+1);
|
|
|
|
if (matches(*argv, "monitor") == 0)
|
|
return netns_monitor(argc-1, argv+1);
|
|
|
|
if (matches(*argv, "attach") == 0)
|
|
return netns_add(argc-1, argv+1, false);
|
|
|
|
fprintf(stderr, "Command \"%s\" is unknown, try \"ip netns help\".\n", *argv);
|
|
exit(-1);
|
|
}
|