#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <sys/ioctl.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/stat.h>
#define O_DIRECTORY 0
#endif
+/* Maximum length of the sun_path member in a struct sockaddr_un, excluding
+ * space for a null terminator. */
+#define MAX_UN_LEN (sizeof(((struct sockaddr_un *) 0)->sun_path) - 1)
+
static int getsockopt_int(int fd, int level, int option, const char *optname,
int *valuep);
int
get_max_fds(void)
{
- static int max_fds = -1;
- if (max_fds < 0) {
+ static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
+ static int max_fds;
+
+ if (ovsthread_once_start(&once)) {
struct rlimit r;
if (!getrlimit(RLIMIT_NOFILE, &r) && rlim_is_finite(r.rlim_cur)) {
max_fds = r.rlim_cur;
VLOG_WARN("failed to obtain fd limit, defaulting to 1024");
max_fds = 1024;
}
+ ovsthread_once_done(&once);
}
+
return max_fds;
}
switch (getaddrinfo(host_name, NULL, &hints, &result)) {
case 0:
- *addr = ((struct sockaddr_in *) result->ai_addr)->sin_addr;
+ *addr = ALIGNED_CAST(struct sockaddr_in *,
+ result->ai_addr)->sin_addr;
freeaddrinfo(result);
return 0;
}
}
-/* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in
- * '*un_len' the size of the sockaddr_un. */
-static void
-make_sockaddr_un__(const char *name, struct sockaddr_un *un, socklen_t *un_len)
+/* Attempts to shorten 'name' by opening a file descriptor for the directory
+ * part of the name and indirecting through /proc/self/fd/<dirfd>/<basename>.
+ * On systems with Linux-like /proc, this works as long as <basename> isn't too
+ * long.
+ *
+ * On success, returns 0 and stores the short name in 'short_name' and a
+ * directory file descriptor to eventually be closed in '*dirfpd'. */
+static int
+shorten_name_via_proc(const char *name, char short_name[MAX_UN_LEN + 1],
+ int *dirfdp)
{
- un->sun_family = AF_UNIX;
- ovs_strzcpy(un->sun_path, name, sizeof un->sun_path);
- *un_len = (offsetof(struct sockaddr_un, sun_path)
- + strlen (un->sun_path) + 1);
+ char *dir, *base;
+ int dirfd;
+ int len;
+
+ if (!LINUX_DATAPATH) {
+ return ENAMETOOLONG;
+ }
+
+ dir = dir_name(name);
+ dirfd = open(dir, O_DIRECTORY | O_RDONLY);
+ if (dirfd < 0) {
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
+ int error = errno;
+
+ VLOG_WARN_RL(&rl, "%s: open failed (%s)", dir, ovs_strerror(error));
+ free(dir);
+
+ return error;
+ }
+ free(dir);
+
+ base = base_name(name);
+ len = snprintf(short_name, MAX_UN_LEN + 1,
+ "/proc/self/fd/%d/%s", dirfd, base);
+ free(base);
+
+ if (len >= 0 && len <= MAX_UN_LEN) {
+ *dirfdp = dirfd;
+ return 0;
+ } else {
+ close(dirfd);
+ return ENAMETOOLONG;
+ }
+}
+
+/* Attempts to shorten 'name' by creating a symlink for the directory part of
+ * the name and indirecting through <symlink>/<basename>. This works on
+ * systems that support symlinks, as long as <basename> isn't too long.
+ *
+ * On success, returns 0 and stores the short name in 'short_name' and the
+ * symbolic link to eventually delete in 'linkname'. */
+static int
+shorten_name_via_symlink(const char *name, char short_name[MAX_UN_LEN + 1],
+ char linkname[MAX_UN_LEN + 1])
+{
+ char *abs, *dir, *base;
+ const char *tmpdir;
+ int error;
+ int i;
+
+ abs = abs_file_name(NULL, name);
+ dir = dir_name(abs);
+ base = base_name(abs);
+ free(abs);
+
+ tmpdir = getenv("TMPDIR");
+ if (tmpdir == NULL) {
+ tmpdir = "/tmp";
+ }
+
+ for (i = 0; i < 1000; i++) {
+ int len;
+
+ len = snprintf(linkname, MAX_UN_LEN + 1,
+ "%s/ovs-un-c-%"PRIu32, tmpdir, random_uint32());
+ error = (len < 0 || len > MAX_UN_LEN ? ENAMETOOLONG
+ : symlink(dir, linkname) ? errno
+ : 0);
+ if (error != EEXIST) {
+ break;
+ }
+ }
+
+ if (!error) {
+ int len;
+
+ fatal_signal_add_file_to_unlink(linkname);
+
+ len = snprintf(short_name, MAX_UN_LEN + 1, "%s/%s", linkname, base);
+ if (len < 0 || len > MAX_UN_LEN) {
+ fatal_signal_unlink_file_now(linkname);
+ error = ENAMETOOLONG;
+ }
+ }
+
+ if (error) {
+ linkname[0] = '\0';
+ }
+ free(dir);
+ free(base);
+
+ return error;
}
/* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in
* '*un_len' the size of the sockaddr_un.
*
- * Returns 0 on success, otherwise a positive errno value. On success,
- * '*dirfdp' is either -1 or a nonnegative file descriptor that the caller
- * should close after using '*un' to bind or connect. On failure, '*dirfdp' is
- * -1. */
+ * Returns 0 on success, otherwise a positive errno value.
+ *
+ * Uses '*dirfdp' and 'linkname' to store references to data when the caller no
+ * longer needs to use 'un'. On success, freeing these references with
+ * free_sockaddr_un() is mandatory to avoid a leak; on failure, freeing them is
+ * unnecessary but harmless. */
static int
make_sockaddr_un(const char *name, struct sockaddr_un *un, socklen_t *un_len,
- int *dirfdp)
+ int *dirfdp, char linkname[MAX_UN_LEN + 1])
{
- enum { MAX_UN_LEN = sizeof un->sun_path - 1 };
+ char short_name[MAX_UN_LEN + 1];
*dirfdp = -1;
+ linkname[0] = '\0';
if (strlen(name) > MAX_UN_LEN) {
- static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
-
- if (LINUX_DATAPATH) {
- /* 'name' is too long to fit in a sockaddr_un, but we have a
- * workaround for that on Linux: shorten it by opening a file
- * descriptor for the directory part of the name and indirecting
- * through /proc/self/fd/<dirfd>/<basename>. */
- char *dir, *base;
- char *short_name;
- int dirfd;
-
- dir = dir_name(name);
- base = base_name(name);
-
- dirfd = open(dir, O_DIRECTORY | O_RDONLY);
- if (dirfd < 0) {
- free(base);
- free(dir);
- return errno;
- }
-
- short_name = xasprintf("/proc/self/fd/%d/%s", dirfd, base);
- free(dir);
- free(base);
-
- if (strlen(short_name) <= MAX_UN_LEN) {
- make_sockaddr_un__(short_name, un, un_len);
- free(short_name);
- *dirfdp = dirfd;
- return 0;
- }
- free(short_name);
- close(dirfd);
+ /* 'name' is too long to fit in a sockaddr_un. Try a workaround. */
+ int error = shorten_name_via_proc(name, short_name, dirfdp);
+ if (error == ENAMETOOLONG) {
+ error = shorten_name_via_symlink(name, short_name, linkname);
+ }
+ if (error) {
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum "
- "%d bytes (even shortened)", name, MAX_UN_LEN);
- } else {
- /* 'name' is too long and we have no workaround. */
- VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum "
- "%d bytes", name, MAX_UN_LEN);
+ "%zu bytes", name, MAX_UN_LEN);
+ return error;
}
- return ENAMETOOLONG;
- } else {
- make_sockaddr_un__(name, un, un_len);
- return 0;
+ name = short_name;
+ }
+
+ un->sun_family = AF_UNIX;
+ ovs_strzcpy(un->sun_path, name, sizeof un->sun_path);
+ *un_len = (offsetof(struct sockaddr_un, sun_path)
+ + strlen (un->sun_path) + 1);
+ return 0;
+}
+
+/* Clean up after make_sockaddr_un(). */
+static void
+free_sockaddr_un(int dirfd, const char *linkname)
+{
+ if (dirfd >= 0) {
+ close(dirfd);
+ }
+ if (linkname[0]) {
+ fatal_signal_unlink_file_now(linkname);
}
}
}
if (bind_path) {
+ char linkname[MAX_UN_LEN + 1];
struct sockaddr_un un;
socklen_t un_len;
int dirfd;
}
fatal_signal_add_file_to_unlink(bind_path);
- error = make_sockaddr_un(bind_path, &un, &un_len, &dirfd);
+ error = make_sockaddr_un(bind_path, &un, &un_len, &dirfd, linkname);
if (!error) {
error = bind_unix_socket(fd, (struct sockaddr *) &un, un_len);
}
- if (dirfd >= 0) {
- close(dirfd);
- }
+ free_sockaddr_un(dirfd, linkname);
+
if (error) {
goto error;
}
}
if (connect_path) {
+ char linkname[MAX_UN_LEN + 1];
struct sockaddr_un un;
socklen_t un_len;
int dirfd;
- error = make_sockaddr_un(connect_path, &un, &un_len, &dirfd);
+ error = make_sockaddr_un(connect_path, &un, &un_len, &dirfd, linkname);
if (!error
&& connect(fd, (struct sockaddr*) &un, un_len)
&& errno != EINPROGRESS) {
error = errno;
}
- if (dirfd >= 0) {
- close(dirfd);
- }
+ free_sockaddr_un(dirfd, linkname);
+
if (error) {
goto error;
}
int
get_null_fd(void)
{
- static int null_fd = -1;
- if (null_fd < 0) {
+ static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
+ static int null_fd;
+
+ if (ovsthread_once_start(&once)) {
null_fd = open("/dev/null", O_RDWR);
if (null_fd < 0) {
int error = errno;
VLOG_ERR("could not open /dev/null: %s", ovs_strerror(error));
- return -error;
+ null_fd = -error;
}
+ ovsthread_once_done(&once);
}
+
return null_fd;
}
goto error;
} else {
size_t n_fds = (p->cmsg_len - CMSG_LEN(0)) / sizeof *fds;
- const int *fds_data = (const int *) CMSG_DATA(p);
+ const int *fds_data = ALIGNED_CAST(const int *, CMSG_DATA(p));
ovs_assert(n_fds > 0);
if (n_fds > SOUTIL_MAX_FDS) {
*n_fdsp = 0;
return EPROTO;
}
+
+/* Calls ioctl() on an AF_INET sock, passing the specified 'command' and
+ * 'arg'. Returns 0 if successful, otherwise a positive errno value. */
+int
+af_inet_ioctl(unsigned long int command, const void *arg)
+{
+ static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
+ static int sock;
+
+ if (ovsthread_once_start(&once)) {
+ sock = socket(AF_INET, SOCK_DGRAM, 0);
+ if (sock < 0) {
+ sock = -errno;
+ VLOG_ERR("failed to create inet socket: %s", ovs_strerror(errno));
+ }
+ ovsthread_once_done(&once);
+ }
+
+ return (sock < 0 ? -sock
+ : ioctl(sock, command, arg) == -1 ? errno
+ : 0);
+}
+
+int
+af_inet_ifreq_ioctl(const char *name, struct ifreq *ifr, unsigned long int cmd,
+ const char *cmd_name)
+{
+ int error;
+
+ ovs_strzcpy(ifr->ifr_name, name, sizeof ifr->ifr_name);
+ error = af_inet_ioctl(cmd, ifr);
+ if (error) {
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
+ VLOG_DBG_RL(&rl, "%s: ioctl(%s) failed: %s", name, cmd_name,
+ ovs_strerror(error));
+ }
+ return error;
+}
+