- Add vnode-backed swap space specification support. This is enabled when

  device names "md" or "md[0-9]*" and a "file" option are specified in
  /etc/fstab like this:

  md    none    swap    sw,file=/swap.bin       0       0

- Add GBDE/GELI encrypted swap space specification support, which
  rc.d/encswap supported.  The /etc/fstab lines are like the following:

  /dev/ada1p1.bde       none    swap    sw      0       0
  /dev/ada1p2.eli       none    swap    sw      0       0

  .eli devices accepts aalgo, ealgo, keylen, and sectorsize as options.

  swapctl(8) can understand an encrypted device in the command line
  like this:

  # swapctl -a /dev/ada2p1.bde

- "-L" flag is added to support "late" option to defer swapon until
  rc.d/mountlate runs.

- rc.d script change:

    rc.d/encswap -> removed
    rc.d/addswap -> just display a warning message if $swapfile is defined
    rc.d/swap1 -> renamed to rc.d/swap
    rc.d/swaplate -> newly added to support "late" option

These changes alleviate a race condition between device creation/removal
and swapon/swapoff.

MFC after:	1 week
Reviewed by:	wblock (manual page)

2 files changed, 566 insertions, 29 deletions

diff --git a/sbin/swapon/swapon.8 b/sbin/swapon/swapon.8
index 5602a9a..ec2ad72 100644
--- a/sbin/swapon/swapon.8
+++ b/sbin/swapon/swapon.8
@@ -28,7 +28,7 @@
 .\"     @(#)swapon.8	8.1 (Berkeley) 6/5/93
 .\" $FreeBSD$
 .\"
-.Dd June 23, 2008
+.Dd June 21, 2013
 .Dt SWAPON 8
 .Os
 .Sh NAME
@@ -38,11 +38,11 @@
 .Nm swapon
 .Oo Fl F Ar fstab
 .Oc
-.Fl aq | Ar
+.Fl aLq | Ar
 .Nm swapoff
 .Oo Fl F Ar fstab
 .Oc
-.Fl aq | Ar
+.Fl aLq | Ar
 .Nm swapctl
 .Op Fl AghklmsU
 .Oo
@@ -74,10 +74,19 @@ option is used, all swap devices in
 .Pa /etc/fstab
 will be added, unless their
 .Dq noauto
+or
+.Dq late
 option is also set.
 If the
+.Fl L
+option is specified,
+swap devices with the
+.Dq late
+option will be added as well as ones with no option.
+If the
 .Fl q
-option is used informational messages will not be
+option is used,
+informational messages will not be
 written to standard output when a swap device is added.
 .Pp
 The
@@ -89,10 +98,19 @@ option is used, all swap devices in
 .Pa /etc/fstab
 will be removed, unless their
 .Dq noauto
+or
+.Dq late
 option is also set.
 If the
+.Fl L
+option is specified,
+swap devices with the
+.Dq late
+option will be removed as well as ones with no option.
+If the
 .Fl q
-option is used informational messages will not be
+option is used,
+informational messages will not be
 written to standard output when a swap device is removed.
 Note that
 .Nm swapoff
diff --git a/sbin/swapon/swapon.c b/sbin/swapon/swapon.c
index 5b9a0ed..55beb5b 100644
--- a/sbin/swapon/swapon.c
+++ b/sbin/swapon/swapon.c
@@ -41,35 +41,51 @@ static char sccsid[] = "@(#)swapon.c	8.1 (Berkeley) 6/5/93";
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
-#include <sys/stat.h>
 #include <sys/param.h>
+#include <sys/types.h>
+#include <sys/mdioctl.h>
+#include <sys/stat.h>
 #include <sys/sysctl.h>
+#include <sys/wait.h>
 #include <vm/vm_param.h>
 
 #include <err.h>
 #include <errno.h>
+#include <fcntl.h>
+#include <fnmatch.h>
 #include <fstab.h>
+#include <libgen.h>
+#include <libutil.h>
+#include <limits.h>
+#include <paths.h>
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
-#include <fcntl.h>
-#include <libutil.h>
 
 static void usage(void);
-static int swap_on_off(char *name, int ignoreebusy);
+static const char *swap_on_off(char *, int, char *);
+static const char *swap_on_off_gbde(char *, int);
+static const char *swap_on_off_geli(char *, char *, int);
+static const char *swap_on_off_md(char *, char *, int);
+static const char *swap_on_off_sfile(char *, int);
 static void swaplist(int, int, int);
+static int run_cmd(int *, const char *, ...) __printflike(2, 3);
 
 static enum { SWAPON, SWAPOFF, SWAPCTL } orig_prog, which_prog = SWAPCTL;
 
+static int qflag;
+
 int
 main(int argc, char **argv)
 {
 	struct fstab *fsp;
+	const char *swfile;
 	char *ptr;
 	int ret;
 	int ch, doall;
-	int sflag = 0, lflag = 0, hflag = 0, qflag = 0;
+	int sflag = 0, lflag = 0, late = 0, hflag = 0;
 	const char *etc_fstab;
 
 	if ((ptr = strrchr(argv[0], '/')) == NULL)
@@ -82,7 +98,7 @@ main(int argc, char **argv)
 	
 	doall = 0;
 	etc_fstab = NULL;
-	while ((ch = getopt(argc, argv, "AadghklmqsUF:")) != -1) {
+	while ((ch = getopt(argc, argv, "AadghklLmqsUF:")) != -1) {
 		switch(ch) {
 		case 'A':
 			if (which_prog == SWAPCTL) {
@@ -116,6 +132,9 @@ main(int argc, char **argv)
 		case 'l':
 			lflag = 1;
 			break;
+		case 'L':
+			late = 1;
+			break;
 		case 'm':
 			hflag = 'M';
 			break;
@@ -145,6 +164,7 @@ main(int argc, char **argv)
 	argv += optind;
 
 	ret = 0;
+	swfile = NULL;
 	if (etc_fstab != NULL)
 		setfstab(etc_fstab);
 	if (which_prog == SWAPON || which_prog == SWAPOFF) {
@@ -154,27 +174,37 @@ main(int argc, char **argv)
 					continue;
 				if (strstr(fsp->fs_mntops, "noauto"))
 					continue;
-				if (swap_on_off(fsp->fs_spec, 1)) {
+				if (which_prog != SWAPOFF &&
+				    strstr(fsp->fs_mntops, "late") &&
+				    !late)
+					continue;
+				swfile = swap_on_off(fsp->fs_spec, 1,
+				    fsp->fs_mntops);
+				if (swfile == NULL) {
 					ret = 1;
-				} else {
-					if (!qflag) {
-						printf("%s: %sing %s as swap device\n",
-						    getprogname(),
-						    which_prog == SWAPOFF ? "remov" : "add",
-						    fsp->fs_spec);
-					}
+					continue;
+				}
+				if (!qflag) {
+					printf("%s: %sing %s as swap device\n",
+					    getprogname(),
+					    (which_prog == SWAPOFF) ?
+					    "remov" : "add", swfile);
 				}
 			}
 		}
 		else if (!*argv)
 			usage();
 		for (; *argv; ++argv) {
-			if (swap_on_off(*argv, 0)) {
+			swfile = swap_on_off(*argv, 0, NULL);
+			if (swfile == NULL) {
 				ret = 1;
-			} else if (orig_prog == SWAPCTL) {
+				continue;
+			}
+			if (orig_prog == SWAPCTL) {
 				printf("%s: %sing %s as swap device\n",
-				    getprogname(), which_prog == SWAPOFF ? "remov" : "add",
-				    *argv);
+				    getprogname(),
+				    (which_prog == SWAPOFF) ? "remov" : "add",
+				    swfile);
 			}
 		}
 	} else {
@@ -186,14 +216,503 @@ main(int argc, char **argv)
 	exit(ret);
 }
 
+static const char *
+swap_on_off(char *name, int doingall, char *mntops)
+{
+	char base[PATH_MAX];
+
+	/* Swap on vnode-backed md(4) device. */
+	if (mntops != NULL &&
+	    (fnmatch(_PATH_DEV MD_NAME "[0-9]*", name, 0) != FNM_NOMATCH ||
+	     fnmatch(MD_NAME "[0-9]*", name, 0) != FNM_NOMATCH ||
+	     strncmp(_PATH_DEV MD_NAME, name,
+		sizeof(_PATH_DEV) + sizeof(MD_NAME)) == 0 ||
+	     strncmp(MD_NAME, name, sizeof(MD_NAME)) == 0))
+		return (swap_on_off_md(name, mntops, doingall));
+
+	/* Swap on encrypted device by GEOM_BDE. */
+	basename_r(name, base);
+	if (fnmatch("*.bde", base, 0) != FNM_NOMATCH)
+		return (swap_on_off_gbde(name, doingall));
+
+	/* Swap on encrypted device by GEOM_ELI. */
+	if (fnmatch("*.eli", base, 0) != FNM_NOMATCH)
+		return (swap_on_off_geli(name, mntops, doingall));
+
+	/* Swap on special file. */
+	return (swap_on_off_sfile(name, doingall));
+}
+
+static const char *
+swap_on_off_gbde(char *name, int doingall)
+{
+	const char *ret;
+	char pass[64 * 2 + 1], bpass[64];
+	char *devname, *p;
+	int i, fd, error;
+
+	devname = strdup(name);
+	p = strrchr(devname, '.');
+	if (p == NULL) {
+		warnx("%s: Malformed device name", name);
+		return (NULL);
+	}
+	*p = '\0';
+
+	fd = -1;
+	switch (which_prog) {
+	case SWAPON:
+		arc4random_buf(bpass, sizeof(bpass));
+		for (i = 0; i < (int)sizeof(bpass); i++)
+			sprintf(&pass[2 * i], "%02x", bpass[i]);
+		pass[sizeof(pass) - 1] = '\0';
+
+		error = run_cmd(&fd, "%s init %s -P %s", _PATH_GBDE,
+		    devname, pass);
+		if (error) {
+			/* bde device found.  Ignore it. */
+			close(fd);
+			if (!qflag)
+				warnx("%s: Device already in use", name);
+			return (NULL);
+		}
+		close(fd);
+		error = run_cmd(&fd, "%s attach %s -p %s", _PATH_GBDE,
+		    devname, pass);
+		if (error) {
+			close(fd);
+			warnx("gbde (attach) error: %s", name);
+			return (NULL);
+		}
+		break;
+	case SWAPOFF:
+		break;
+	default:
+		return (NULL);
+		break;
+	}
+	if (fd != -1)
+		close(fd);
+	ret = swap_on_off_sfile(name, doingall);
+
+	fd = -1;
+	switch (which_prog) {
+	case SWAPOFF:
+		error = run_cmd(&fd, "%s detach %s", _PATH_GBDE, devname);
+		if (error) {
+			/* bde device not found.  Ignore it. */
+			if (!qflag)
+				warnx("%s: Device not found", devname);
+			return (NULL);
+		}
+		break;
+	default:
+		return (NULL);
+		break;
+	}
+
+	if (fd != -1)
+		close(fd);
+	return (ret);
+}
+
+static const char *
+swap_on_off_geli(char *name, char *mntops, int doingall)
+{
+	const char *ops, *aalgo, *ealgo, *keylen_str, *sectorsize_str;
+	char *devname, *p;
+	char args[4096];
+	struct stat sb;
+	int fd, error, keylen, sectorsize;
+	u_long ul;
+
+	devname = strdup(name);
+	p = strrchr(devname, '.');
+	if (p == NULL) {
+		warnx("%s: Malformed device name", name);
+		return (NULL);
+	}
+	*p = '\0';
+
+	ops = strdup(mntops);
+
+	/* Default parameters for geli(8). */
+	aalgo = "hmac/sha256";
+	ealgo = "aes";
+	keylen = 256;
+	sectorsize = 4096;
+
+	if ((p = strstr(ops, "aalgo=")) != NULL) {
+		aalgo = p + sizeof("aalgo=") - 1;
+		p = strchr(aalgo, ',');
+		if (p != NULL)
+			*p = '\0';
+	}
+	if ((p = strstr(ops, "ealgo=")) != NULL) {
+		ealgo = p + sizeof("ealgo=") - 1;
+		p = strchr(ealgo, ',');
+		if (p != NULL)
+			*p = '\0';
+	}
+	if ((p = strstr(ops, "keylen=")) != NULL) {
+		keylen_str = p + sizeof("keylen=") - 1;
+		p = strchr(keylen_str, ',');
+		if (p != NULL)
+			*p = '\0';
+		errno = 0;
+		ul = strtoul(keylen_str, &p, 10);
+		if (errno == 0) {
+			if (*p != '\0' || ul > INT_MAX)
+				errno = EINVAL;
+		}
+		if (errno) {
+			warn("Invalid keylen: %s", keylen_str);
+			return (NULL);
+		}
+		keylen = (int)ul;
+	}
+	if ((p = strstr(ops, "sectorsize=")) != NULL) {
+		sectorsize_str = p + sizeof("sectorsize=") - 1;
+		p = strchr(sectorsize_str, ',');
+		if (p != NULL)
+			*p = '\0';
+		errno = 0;
+		ul = strtoul(sectorsize_str, &p, 10);
+		if (errno == 0) {
+			if (*p != '\0' || ul > INT_MAX)
+				errno = EINVAL;
+		}
+		if (errno) {
+			warn("Invalid sectorsize: %s", sectorsize_str);
+			return (NULL);
+		}
+		sectorsize = (int)ul;
+	}
+	snprintf(args, sizeof(args), "-a %s -e %s -l %d -s %d -d",
+	    aalgo, ealgo, keylen, sectorsize);
+	args[sizeof(args) - 1] = '\0';
+	free((void *)ops);
+
+	fd = -1;
+	switch (which_prog) {
+	case SWAPON:
+		error = run_cmd(&fd, "%s onetime %s %s", _PATH_GELI, args,
+		    devname);
+		if (error) {
+			/* eli device found.  Ignore it. */
+			close(fd);
+			if (!qflag)
+				warnx("%s: Device already in use "
+				    "or invalid parameters", name);
+			return (NULL);
+		}
+		break;
+	case SWAPOFF:
+		if (stat(name, &sb) == -1 && errno == ENOENT) {
+			if (!qflag)
+				warnx("%s: Device not found", name);
+			return (NULL);
+		}
+		break;
+	default:
+		return (NULL);
+		break;
+	}
+	if (fd != -1)
+		close(fd);
+
+	return (swap_on_off_sfile(name, doingall));
+}
+
+static const char *
+swap_on_off_md(char *name, char *mntops, int doingall)
+{
+	FILE *sfd;
+	int fd, mdunit, error;
+	const char *ret;
+	char mdpath[PATH_MAX], linebuf[PATH_MAX];
+	char *p, *vnodefile;
+	size_t linelen;
+	u_long ul;
+
+	fd = -1;
+	sfd = NULL;
+	if (strlen(name) == (sizeof(MD_NAME) - 1))
+		mdunit = -1;
+	else {
+		errno = 0;
+		ul = strtoul(name + 2, &p, 10);
+		if (errno == 0) {
+			if (*p != '\0' || ul > INT_MAX)
+				errno = EINVAL;
+		}
+		if (errno) {
+			warn("Bad device unit: %s", name);
+			return (NULL);
+		}
+		mdunit = (int)ul;
+	}
+
+	vnodefile = NULL;
+	if ((p = strstr(mntops, "file=")) != NULL) {
+		vnodefile = strdup(p + sizeof("file=") - 1);
+		p = strchr(vnodefile, ',');
+		if (p != NULL)
+			*p = '\0';
+	}
+	if (vnodefile == NULL) {
+		warnx("file option not found for %s", name);
+		return (NULL);
+	}
+
+	switch (which_prog) {
+	case SWAPON:
+		if (mdunit == -1) {
+			error = run_cmd(&fd, "%s -l -n -f %s",
+			    _PATH_MDCONFIG, vnodefile);
+			if (error == 0) {
+				/* md device found.  Ignore it. */
+				close(fd);
+				if (!qflag)
+					warnx("%s: Device already in use",
+					    vnodefile);
+				return (NULL);
+			}
+			error = run_cmd(&fd, "%s -a -t vnode -n -f %s",
+			    _PATH_MDCONFIG, vnodefile);
+			if (error) {
+				warnx("mdconfig (attach) error: file=%s",
+				    vnodefile);
+				return (NULL);
+			}
+			sfd = fdopen(fd, "r");
+			if (sfd == NULL) {
+				warn("mdconfig (attach) fdopen error");
+				ret = NULL;
+				goto err;
+			}
+			p = fgetln(sfd, &linelen);
+			if (p == NULL &&
+			    (linelen < 2 || linelen > sizeof(linebuf))) {
+				warn("mdconfig (attach) unexpected output");
+				ret = NULL;
+				goto err;
+			}
+			strncpy(linebuf, p, linelen);
+			linebuf[linelen - 1] = '\0';
+			errno = 0;
+			ul = strtoul(linebuf, &p, 10);
+			if (errno == 0) {
+				if (*p != '\0' || ul > INT_MAX)
+					errno = EINVAL;
+			}
+			if (errno) {
+				warn("mdconfig (attach) unexpected output: %s",
+				    linebuf);
+				ret = NULL;
+				goto err;
+			}
+			mdunit = (int)ul;
+		} else {
+			error = run_cmd(&fd, "%s -l -n -f %s -u %d",
+			    _PATH_MDCONFIG, vnodefile, mdunit);
+			if (error == 0) {
+				/* md device found.  Ignore it. */
+				close(fd);
+				if (!qflag)
+					warnx("md%d on %s: Device already "
+					    "in use", mdunit, vnodefile);
+				return (NULL);
+			}
+			error = run_cmd(NULL, "%s -a -t vnode -u %d -f %s",
+			    _PATH_MDCONFIG, mdunit, vnodefile);
+			if (error) {
+				warnx("mdconfig (attach) error: "
+				    "md%d on file=%s", mdunit, vnodefile);
+				return (NULL);
+			}
+		}
+		break;
+	case SWAPOFF:
+		if (mdunit == -1) {
+			error = run_cmd(&fd, "%s -l -n -f %s",
+			    _PATH_MDCONFIG, vnodefile);
+			if (error) {
+				/* md device not found.  Ignore it. */
+				close(fd);
+				if (!qflag)
+					warnx("md on %s: Device not found",
+					    vnodefile);
+				return (NULL);
+			}
+			sfd = fdopen(fd, "r");
+			if (sfd == NULL) {
+				warn("mdconfig (list) fdopen error");
+				ret = NULL;
+				goto err;
+			}
+			p = fgetln(sfd, &linelen);
+			if (p == NULL &&
+			    (linelen < 2 || linelen > sizeof(linebuf) - 1)) {
+				warn("mdconfig (list) unexpected output");
+				ret = NULL;
+				goto err;
+			}
+			strncpy(linebuf, p, linelen);
+			linebuf[linelen - 1] = '\0';
+			p = strchr(linebuf, ' ');
+			if (p != NULL)
+				*p = '\0';
+			errno = 0;
+			ul = strtoul(linebuf, &p, 10);
+			if (errno == 0) {
+				if (*p != '\0' || ul > INT_MAX)
+					errno = EINVAL;
+			}
+			if (errno) {
+				warn("mdconfig (list) unexpected output: %s",
+				    linebuf);
+				ret = NULL;
+				goto err;
+			}
+			mdunit = (int)ul;
+		} else {
+			error = run_cmd(&fd, "%s -l -n -f %s -u %d",
+			    _PATH_MDCONFIG, vnodefile, mdunit);
+			if (error) {
+				/* md device not found.  Ignore it. */
+				close(fd);
+				if (!qflag)
+					warnx("md%d on %s: Device not found",
+					    mdunit, vnodefile);
+				return (NULL);
+			}
+		}
+		break;
+	default:
+		return (NULL);
+	}
+	snprintf(mdpath, sizeof(mdpath), "%s%s%d", _PATH_DEV,
+	    MD_NAME, mdunit);
+	mdpath[sizeof(mdpath) - 1] = '\0';
+	ret = swap_on_off_sfile(mdpath, doingall);
+
+	switch (which_prog) {
+	case SWAPOFF:
+		if (ret != NULL) {
+			error = run_cmd(NULL, "%s -d -u %d",
+			    _PATH_MDCONFIG, mdunit);
+			if (error)
+				warn("mdconfig (detach) detach failed: %s%s%d",
+				    _PATH_DEV, MD_NAME, mdunit);
+		}
+		break;
+	default:
+		break;
+	}
+err:
+	if (sfd != NULL)
+		fclose(sfd);
+	if (fd != -1)
+		close(fd);
+	return (ret);
+}
+
 static int
-swap_on_off(char *name, int doingall)
+run_cmd(int *ofd, const char *cmdline, ...)
 {
-	if ((which_prog == SWAPOFF ? swapoff(name) : swapon(name)) == -1) {
+	va_list ap;
+	char **argv, **argvp, *cmd, *p;
+	int argc, pid, status, rv;
+	int pfd[2], nfd, dup2dn;
+
+	va_start(ap, cmdline);
+	rv = vasprintf(&cmd, cmdline, ap);
+	if (rv == -1) {
+		warn("%s", __func__);
+		return (rv);
+	}
+	va_end(ap);
+
+	for (argc = 1, p = cmd; (p = strchr(p, ' ')) != NULL; p++)
+		argc++;
+	argv = (char **)malloc(sizeof(*argv) * (argc + 1));
+	for (p = cmd, argvp = argv; (*argvp = strsep(&p, " ")) != NULL;)
+		if (**argvp != '\0' && (++argvp > &argv[argc])) {
+			*argvp = NULL;
+			break;
+		}
+	/* The argv array ends up NULL-terminated here. */
+#if 0
+	{
+		int i;
+
+		fprintf(stderr, "DEBUG: running:");
+		/* Should be equivalent to 'cmd' (before strsep, of course). */
+		for (i = 0; argv[i] != NULL; i++)
+			fprintf(stderr, " %s", argv[i]);
+		fprintf(stderr, "\n");
+	}
+#endif
+	dup2dn = 1;
+	if (ofd != NULL) {
+		if (pipe(&pfd[0]) == -1) {
+			warn("%s: pipe", __func__);
+			return (-1);
+		}
+		*ofd = pfd[0];
+		dup2dn = 0;
+	}
+	pid = fork();
+	switch (pid) {
+	case 0:
+		/* Child process. */
+		if (ofd != NULL)
+			if (dup2(pfd[1], STDOUT_FILENO) < 0)
+				err(1, "dup2 in %s", __func__);
+		nfd = open(_PATH_DEVNULL, O_RDWR);
+		if (nfd == -1)
+			err(1, "%s: open %s", __func__, _PATH_DEVNULL);
+		if (dup2(nfd, STDIN_FILENO) < 0)
+			err(1, "%s: dup2", __func__);
+		if (dup2dn && dup2(nfd, STDOUT_FILENO) < 0)
+			err(1, "%s: dup2", __func__);
+		if (dup2(nfd, STDERR_FILENO) < 0)
+			err(1, "%s: dup2", __func__);
+		execv(argv[0], argv);
+		warn("exec: %s", argv[0]);
+		_exit(-1);
+	case -1:
+		err(1, "%s: fork", __func__);
+	}
+	free(cmd);
+	free(argv);
+	while (waitpid(pid, &status, 0) != pid)
+		;
+	return (WEXITSTATUS(status));
+}
+
+static const char *
+swap_on_off_sfile(char *name, int doingall)
+{
+	int error;
+
+	switch (which_prog) {
+	case SWAPON:
+		error = swapon(name);
+		break;
+	case SWAPOFF:
+		error = swapoff(name);
+		break;
+	default:
+		error = 0;
+		break;
+	}
+	if (error == -1) {
 		switch (errno) {
 		case EBUSY:
 			if (!doingall)
-				warnx("%s: device already in use", name);
+				warnx("%s: Device already in use", name);
 			break;
 		case EINVAL:
 			if (which_prog == SWAPON)
@@ -205,9 +724,9 @@ swap_on_off(char *name, int doingall)
 			warn("%s", name);
 			break;
 		}
-		return(1);
+		return (NULL);
 	}
-	return(0);
+	return (name);
 }
 
 static void
@@ -217,7 +736,7 @@ usage(void)
 	switch(orig_prog) {
 	case SWAPON:
 	case SWAPOFF:
-	    fprintf(stderr, "[-F fstab] -aq | file ...\n");
+	    fprintf(stderr, "[-F fstab] -aLq | file ...\n");
 	    break;
 	case SWAPCTL:
 	    fprintf(stderr, "[-AghklmsU] [-a file ... | -d file ...]\n");