iproute2: Add "ip netns pids" and "ip netns identify"
Add command that go between network namespace names and process
identifiers. The code builds and runs agains older kernels but
only works on Linux 3.8+ kernels where I have fixed stat to work
properly.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
diff --git a/ip/ipnetns.c b/ip/ipnetns.c
index 33765b5..51b1c5e 100644
--- a/ip/ipnetns.c
+++ b/ip/ipnetns.c
@@ -13,6 +13,7 @@
#include <dirent.h>
#include <errno.h>
#include <unistd.h>
+#include <ctype.h>
#include "utils.h"
#include "ip_common.h"
@@ -45,6 +46,8 @@
fprintf(stderr, "Usage: ip netns list\n");
fprintf(stderr, " ip netns add NAME\n");
fprintf(stderr, " ip netns delete NAME\n");
+ fprintf(stderr, " ip netns identify PID\n");
+ fprintf(stderr, " ip netns pids NAME\n");
fprintf(stderr, " ip netns exec NAME cmd ...\n");
fprintf(stderr, " ip netns monitor\n");
return EXIT_FAILURE;
@@ -174,6 +177,145 @@
return EXIT_FAILURE;
}
+static int is_pid(const char *str)
+{
+ int ch;
+ for (; (ch = *str); str++) {
+ if (!isdigit(ch))
+ return 0;
+ }
+ return 1;
+}
+
+static int netns_pids(int argc, char **argv)
+{
+ const char *name;
+ char net_path[MAXPATHLEN];
+ int netns;
+ struct stat netst;
+ DIR *dir;
+ struct dirent *entry;
+
+ if (argc < 1) {
+ fprintf(stderr, "No netns name specified\n");
+ return EXIT_FAILURE;
+ }
+ if (argc > 1) {
+ fprintf(stderr, "extra arguments specified\n");
+ return EXIT_FAILURE;
+ }
+
+ 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));
+ return EXIT_FAILURE;
+ }
+ if (fstat(netns, &netst) < 0) {
+ fprintf(stderr, "Stat of netns failed: %s\n",
+ strerror(errno));
+ return EXIT_FAILURE;
+ }
+ dir = opendir("/proc/");
+ if (!dir) {
+ fprintf(stderr, "Open of /proc failed: %s\n",
+ strerror(errno));
+ return EXIT_FAILURE;
+ }
+ while((entry = readdir(dir))) {
+ char pid_net_path[MAXPATHLEN];
+ 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);
+ }
+ }
+ closedir(dir);
+ return EXIT_SUCCESS;
+
+}
+
+static int netns_identify(int argc, char **argv)
+{
+ const char *pidstr;
+ char net_path[MAXPATHLEN];
+ int netns;
+ struct stat netst;
+ DIR *dir;
+ struct dirent *entry;
+
+ if (argc < 1) {
+ fprintf(stderr, "No pid specified\n");
+ return EXIT_FAILURE;
+ }
+ if (argc > 1) {
+ fprintf(stderr, "extra arguments specified\n");
+ return EXIT_FAILURE;
+ }
+ pidstr = argv[0];
+
+ if (!is_pid(pidstr)) {
+ fprintf(stderr, "Specified string '%s' is not a pid\n",
+ pidstr);
+ return EXIT_FAILURE;
+ }
+
+ 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));
+ return EXIT_FAILURE;
+ }
+ if (fstat(netns, &netst) < 0) {
+ fprintf(stderr, "Stat of netns failed: %s\n",
+ strerror(errno));
+ return EXIT_FAILURE;
+ }
+ dir = opendir(NETNS_RUN_DIR);
+ if (!dir) {
+ /* Succeed treat a missing directory as an empty directory */
+ if (errno == ENOENT)
+ return EXIT_SUCCESS;
+
+ fprintf(stderr, "Failed to open directory %s:%s\n",
+ NETNS_RUN_DIR, strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ while((entry = readdir(dir))) {
+ char name_path[MAXPATHLEN];
+ 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)) {
+ printf("%s\n", entry->d_name);
+ }
+ }
+ closedir(dir);
+ return EXIT_SUCCESS;
+
+}
+
static int netns_delete(int argc, char **argv)
{
const char *name;
@@ -324,6 +466,12 @@
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);