Add "-r rootdisk" growdisk support

agent/Makefile

@@ -1,6 +1,7 @@
 PROG=		cloud-agent
 SRCS=		http.c json.c jsmn.c log.c main.c xml.c
 SRCS+=		azure.c cloudinit.c opennebula.c openstack.c
+SRCS+=		growdisk.c
 BINDIR=		/usr/local/libexec
 MANDIR=		/usr/local/man/man
 

agent/cloud-agent.8

@@ -23,6 +23,7 @@
 .Sh SYNOPSIS
 .Nm cloud-agent
 .Op Fl nuv
+.Op Fl r Ar rootdisk
 .Op Fl t Ar timeout
 .Op Fl U Ar username
 .Ar interface
@@ -53,6 +54,10 @@ configuration.
 Using
 .Dq root
 is supported, but not recommended.
+.It Fl r Ar rootdisk
+Automatically grow the last
+.Ox
+FFS partition of the root disk to use all the available space.
 .It Fl u
 Deprovision and unconfigure the system.
 This deletes keys, passwords, and logs files without asking for permission.
@@ -64,11 +69,12 @@ Enable
 .Nm
 in the
 .Xr hostname.if 5
-of the VM's primary networking interface:
+of the VM's primary networking interface and automatically the last
+partition of the root disk:
 .Bd -literal -offset indent
 # cat /etc/hostname.hvn0
 dhcp
-!/usr/local/libexec/cloud-agent "\e$if"
+!/usr/local/libexec/cloud-agent -r sd0 "\e$if"
 .Ed
 .Sh FILES
 .Bl -tag -width "/usr/local/libexec/cloud-agentX" -compact

agent/growdisk.c

@@ -0,0 +1,149 @@
+/*
+ * Copyright (c) 2019 Reyk Floeter <reyk@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/param.h>	/* DEV_BSIZE */
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/dkio.h>
+#define DKTYPENAMES
+#include <sys/disklabel.h>
+
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <util.h>
+#include <err.h>
+
+#include "main.h"
+
+static uint16_t	 dkcksum(struct disklabel *);
+
+static uint16_t
+dkcksum(struct disklabel *lp)
+{
+	uint16_t	*start, *end, sum;
+	start = (uint16_t *)lp;
+	end = (uint16_t *)&lp->d_partitions[lp->d_npartitions];
+	for (sum = 0; start < end;)
+		sum ^= *start++;
+	return (sum);
+}
+
+int
+growdisk(struct system_config *sc)
+{
+	char			 c, last_part = 0, *out, *path = NULL;
+	int			 ret = -1, i, errfd, outfd;
+	struct partition	*pp, *p = NULL;
+	struct disklabel	 lp;
+	int			 fd;
+	uint16_t		 cksum;
+
+	/*
+	 * Grow the OpenBSD MBR partition
+	 */
+
+	/* XXX this is a bit ugly but easier to do */
+	if (shellout("e 3\n\n\n\n*\nw\nq\n", &out,
+	    "fdisk", "-e", sc->sc_rootdisk, NULL) != 0) {
+		log_warnx("failed to grow OpenBSD partition");
+		return (-1);
+	}
+	free(out);
+
+	/*
+	 * Grow the last partition in the disklabel
+	 */
+
+	if ((fd = opendev(sc->sc_rootdisk,
+	    O_RDWR, OPENDEV_PART, NULL)) == -1) {
+		log_warn("failed to open %s", sc->sc_rootdisk);
+		return (-1);
+	}
+
+	if (ioctl(fd, DIOCGDINFO, &lp) == -1) {
+		log_warn("failed to get disklabel");
+		goto done;
+	}
+
+	if (lp.d_magic != DISKMAGIC || lp.d_magic2 != DISKMAGIC) {
+		log_warnx("invalid disklabel magic bytes");
+		goto done;
+	}
+	cksum = lp.d_checksum;
+	lp.d_checksum = 0;
+
+	if (dkcksum(&lp) != cksum) {
+		log_warnx("invalid disklabel checksum");
+		goto done;
+	}
+
+	pp = lp.d_partitions;
+	for (i = 0, pp = lp.d_partitions; i < lp.d_npartitions; i++, pp++) {
+		if (!DL_GETPSIZE(pp))
+			continue;
+		c = 'a' + i;
+		if (pp->p_fstype == FS_BSDFFS) {
+			last_part = c;
+			p = pp;
+		}
+	}
+
+	if (last_part == 0) {
+		log_warnx("last BSD partition not found");
+		goto done;
+	}
+
+	/* Update OpenBSD boundaries */
+	DL_SETBEND(&lp, DL_GETDSIZE(&lp) - DL_GETBSTART(&lp));
+
+	/* Update the size of the last partition */
+	DL_SETPSIZE(p, DL_GETBEND(&lp) - DL_GETPOFFSET(p));
+
+	lp.d_checksum = dkcksum(&lp);
+
+	if (ioctl(fd, DIOCWDINFO, &lp) == -1) {
+		log_warn("failed to write disklabel");
+		goto done;
+	}
+
+	/*
+	 * Grow the filesystem
+	 */
+
+	if (asprintf(&path, "/dev/%s%c", sc->sc_rootdisk, last_part) == -1)
+		goto done;
+
+	errfd = disable_output(sc, STDERR_FILENO);
+	outfd = disable_output(sc, STDOUT_FILENO);
+
+	(void)shell("umount", "-f", path, NULL);
+	(void)shell("growfs", "-yq", path, NULL);
+	if ((ret = shell("fsck", "-y", path, NULL)) != 0)
+		ret = -1;
+
+	enable_output(sc, STDERR_FILENO, errfd);
+	enable_output(sc, STDOUT_FILENO, outfd);
+
+	ret = 0;
+ done:
+	free(path);
+	close(fd);
+	return (ret);
+}

agent/main.c

@@ -43,7 +43,8 @@
 #include "xml.h"
 
 __dead void	 usage(void);
-static struct system_config	*agent_init(const char *, int, int);
+static struct system_config
+		*agent_init(const char *, const char *, int, int);
 static int	 agent_configure(struct system_config *);
 static int	 agent_network(struct system_config *);
 static void	 agent_free(struct system_config *);
@@ -306,7 +307,7 @@ get_word(const unsigned char *ptr, size_t len)
 }
 
 static struct system_config *
-agent_init(const char *ifname, int dryrun, int timeout)
+agent_init(const char *ifname, const char *rootdisk, int dryrun, int timeout)
 {
 	struct system_config	*sc;
 	int			 fd, ret;
@@ -318,6 +319,7 @@ agent_init(const char *ifname, int dryrun, int timeout)
 	sc->sc_cdrom = "/dev/cd0c";
 	sc->sc_dryrun = dryrun ? 1 : 0;
 	sc->sc_timeout = agent_timeout = timeout < 1 ? -1 : timeout * 1000;
+	sc->sc_rootdisk = rootdisk;
 	TAILQ_INIT(&sc->sc_pubkeys);
 	TAILQ_INIT(&sc->sc_netaddrs);
 
@@ -1089,8 +1091,8 @@ usage(void)
 {
 	extern char	*__progname;
 
-	fprintf(stderr, "usage: %s [-nuv] [-t 3] [-U puffy] interface\n",
+	fprintf(stderr, "usage: %s [-nuv] [-r rootdisk] [-t 3] [-U puffy] "
-	    __progname);
+	    "interface\n", __progname);
 	exit(1);
 }
 
@@ -1130,19 +1132,19 @@ main(int argc, char *const *argv)
 	struct system_config	*sc;
 	int			 verbose = 0, dryrun = 0, unconfigure = 0;
 	int			 ch, ret, timeout = CONNECT_TIMEOUT;
-	const char		*error = NULL;
+	const char		*error = NULL, *rootdisk = NULL;
 	char			*args, *username = NULL;
 
 	if ((args = get_args(argc, argv)) == NULL)
 		fatalx("failed to save args");
 
-	while ((ch = getopt(argc, argv, "nvt:U:u")) != -1) {
+	while ((ch = getopt(argc, argv, "nr:t:U:uv")) != -1) {
 		switch (ch) {
 		case 'n':
 			dryrun = 1;
 			break;
-		case 'v':
+		case 'r':
-			verbose += 2;
+			rootdisk = optarg;
 			break;
 		case 't':
 			timeout = strtonum(optarg, -1, 86400, &error);
@@ -1156,6 +1158,9 @@ main(int argc, char *const *argv)
 		case 'u':
 			unconfigure = 1;
 			break;
+		case 'v':
+			verbose += 2;
+			break;
 		default:
 			usage();
 		}
@@ -1176,11 +1181,18 @@ main(int argc, char *const *argv)
 	if (argc != 1)
 		usage();
 
-	if (pledge("stdio cpath rpath wpath exec proc dns inet", NULL) == -1)
+	if (pledge(rootdisk == NULL ?
+	    "stdio cpath rpath wpath exec proc dns inet" :
+	    "stdio cpath rpath wpath exec proc dns inet disklabel",
+	    NULL) == -1)
 		fatal("pledge");
 
-	if ((sc = agent_init(argv[0], dryrun, timeout)) == NULL)
+	if ((sc = agent_init(argv[0], rootdisk, dryrun, timeout)) == NULL)
 		fatalx("agent");
+
+	if (rootdisk != NULL && growdisk(sc) == -1)
+		fatalx("failed to grow %s", rootdisk);
+
 	sc->sc_args = args;
 	if (username != NULL) {
 		free(sc->sc_username);

agent/main.h

@@ -82,6 +82,7 @@ struct system_config {
 	const char		*sc_ovfenv;
 	const char		*sc_interface;
 	const char		*sc_cdrom;
+	const char		*sc_rootdisk;
 	int			 sc_mount;
 
 	struct source		 sc_addr;
@@ -129,6 +130,9 @@ int	 opennebula(struct system_config *);
 /* openstack.c */
 int	 openstack(struct system_config *);
 
+/* growdisk.c */
+int	 growdisk(struct system_config *);
+
 /* main.c */
 int	 shell(const char *, ...);
 int	 shellout(const char *, char **, const char *, ...);