Create the GELIBOOT GEOM_ELI flag

This flag indicates that the user wishes to use the GELIBOOT feature to boot from a fully encrypted root file system.
Currently, GELIBOOT does not support key files, and in the future when it does, they will be loaded differently.
Due to the design of GELI, and the desire for secrecy, the GELI metadata does not know if key files are used or not, it just adds the key material (if any) to the HMAC before the optional passphrase, so there is no way to tell if a GELI partition requires key files or not.

Since the GELIBOOT code in boot2 and the loader does not support keys, they will now only attempt to attach if this flag is set. This will stop GELIBOOT from prompting for passwords to GELIs that it cannot decrypt, disrupting the boot process

PR:		208251
Reviewed by:	ed, oshogbo, wblock
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D5867

2 files changed, 55 insertions, 11 deletions

diff --git a/sbin/geom/class/eli/geli.8 b/sbin/geom/class/eli/geli.8
index ed425da..e8a1ef0 100644
--- a/sbin/geom/class/eli/geli.8
+++ b/sbin/geom/class/eli/geli.8
@@ -51,7 +51,7 @@ utility:
 .Pp
 .Nm
 .Cm init
-.Op Fl bPTv
+.Op Fl bgPTv
 .Op Fl a Ar aalgo
 .Op Fl B Ar backupfile
 .Op Fl e Ar ealgo
@@ -88,7 +88,7 @@ utility:
 .Ar prov
 .Nm
 .Cm configure
-.Op Fl bBtT
+.Op Fl bBgGtT
 .Ar prov ...
 .Nm
 .Cm setkey
@@ -293,6 +293,11 @@ The default and recommended algorithm is
 .Nm AES-XTS .
 .Nm NULL
 is unencrypted.
+.It Fl g
+Enable booting from this encrypted root filesystem.
+The boot loader prompts for the passphrase and loads
+.Xr loader 8
+from the encrypted partition.
 .It Fl i Ar iterations
 Number of iterations to use with PKCS#5v2 when processing User Key
 passphrase component.
@@ -485,6 +490,13 @@ For more information, see the description of the
 subcommand.
 .It Fl B
 Remove the BOOT flag from the given providers.
+.It Fl g
+Enable booting from this encrypted root filesystem.
+The boot loader prompts for the passphrase and loads
+.Xr loader 8
+from the encrypted partition.
+.It Fl G
+Deactivate booting from this encrypted root partition.
 .It Fl t
 Enable TRIM/UNMAP passthru.
 For more information, see the description of the
diff --git a/sbin/geom/class/eli/geom_eli.c b/sbin/geom/class/eli/geom_eli.c
index 0c6ca2c..c804622 100644
--- a/sbin/geom/class/eli/geom_eli.c
+++ b/sbin/geom/class/eli/geom_eli.c
@@ -82,13 +82,13 @@ static int eli_backup_create(struct gctl_req *req, const char *prov,
 /*
  * Available commands:
  *
- * init [-bhPv] [-a aalgo] [-B backupfile] [-e ealgo] [-i iterations] [-l keylen] [-J newpassfile] [-K newkeyfile] [-V version] prov
+ * init [-bgPTv] [-a aalgo] [-B backupfile] [-e ealgo] [-i iterations] [-l keylen] [-J newpassfile] [-K newkeyfile] [-s sectorsize] [-V version] prov
  * label - alias for 'init'
  * attach [-dprv] [-j passfile] [-k keyfile] prov
  * detach [-fl] prov ...
  * stop - alias for 'detach'
  * onetime [-d] [-a aalgo] [-e ealgo] [-l keylen] prov
- * configure [-bB] prov ...
+ * configure [-bBgGtT] prov ...
  * setkey [-pPv] [-n keyno] [-j passfile] [-J newpassfile] [-k keyfile] [-K newkeyfile] prov
  * delkey [-afv] [-n keyno] prov
  * suspend [-v] -a | prov ...
@@ -108,6 +108,7 @@ struct g_command class_commands[] = {
 		{ 'b', "boot", NULL, G_TYPE_BOOL },
 		{ 'B', "backupfile", "", G_TYPE_STRING },
 		{ 'e', "ealgo", "", G_TYPE_STRING },
+		{ 'g', "geliboot", NULL, G_TYPE_BOOL },
 		{ 'i', "iterations", "-1", G_TYPE_NUMBER },
 		{ 'J', "newpassfile", G_VAL_OPTIONAL, G_TYPE_STRING | G_TYPE_MULTI },
 		{ 'K', "newkeyfile", G_VAL_OPTIONAL, G_TYPE_STRING | G_TYPE_MULTI },
@@ -118,7 +119,7 @@ struct g_command class_commands[] = {
 		{ 'V', "mdversion", "-1", G_TYPE_NUMBER },
 		G_OPT_SENTINEL
 	    },
-	    "[-bPTv] [-a aalgo] [-B backupfile] [-e ealgo] [-i iterations] [-l keylen] [-J newpassfile] [-K newkeyfile] [-s sectorsize] [-V version] prov"
+	    "[-bgPTv] [-a aalgo] [-B backupfile] [-e ealgo] [-i iterations] [-l keylen] [-J newpassfile] [-K newkeyfile] [-s sectorsize] [-V version] prov"
 	},
 	{ "label", G_FLAG_VERBOSE, eli_main,
 	    {
@@ -126,6 +127,7 @@ struct g_command class_commands[] = {
 		{ 'b', "boot", NULL, G_TYPE_BOOL },
 		{ 'B', "backupfile", "", G_TYPE_STRING },
 		{ 'e', "ealgo", "", G_TYPE_STRING },
+		{ 'g', "geliboot", NULL, G_TYPE_BOOL },
 		{ 'i', "iterations", "-1", G_TYPE_NUMBER },
 		{ 'J', "newpassfile", G_VAL_OPTIONAL, G_TYPE_STRING | G_TYPE_MULTI },
 		{ 'K', "newkeyfile", G_VAL_OPTIONAL, G_TYPE_STRING | G_TYPE_MULTI },
@@ -180,11 +182,13 @@ struct g_command class_commands[] = {
 	    {
 		{ 'b', "boot", NULL, G_TYPE_BOOL },
 		{ 'B', "noboot", NULL, G_TYPE_BOOL },
+		{ 'g', "geliboot", NULL, G_TYPE_BOOL },
+		{ 'G', "nogeliboot", NULL, G_TYPE_BOOL },
 		{ 't', "trim", NULL, G_TYPE_BOOL },
 		{ 'T', "notrim", NULL, G_TYPE_BOOL },
 		G_OPT_SENTINEL
 	    },
-	    "[-bBtT] prov ..."
+	    "[-bBgGtT] prov ..."
 	},
 	{ "setkey", G_FLAG_VERBOSE, eli_main,
 	    {
@@ -702,6 +706,8 @@ eli_init(struct gctl_req *req)
 	md.md_flags = 0;
 	if (gctl_get_int(req, "boot"))
 		md.md_flags |= G_ELI_FLAG_BOOT;
+	if (gctl_get_int(req, "geliboot"))
+		md.md_flags |= G_ELI_FLAG_GELIBOOT;
 	if (gctl_get_int(req, "notrim"))
 		md.md_flags |= G_ELI_FLAG_NODELETE;
 	md.md_ealgo = CRYPTO_ALGORITHM_MIN - 1;
@@ -906,7 +912,7 @@ eli_attach(struct gctl_req *req)
 
 static void
 eli_configure_detached(struct gctl_req *req, const char *prov, int boot,
- int trim)
+ int geliboot, int trim)
 {
 	struct g_eli_metadata md;
 	bool changed = 0;
@@ -928,6 +934,20 @@ eli_configure_detached(struct gctl_req *req, const char *prov, int boot,
 		changed = 1;
 	}
 
+	if (geliboot == 1 && (md.md_flags & G_ELI_FLAG_GELIBOOT)) {
+		if (verbose)
+			printf("GELIBOOT flag already configured for %s.\n", prov);
+	} else if (geliboot == 0 && !(md.md_flags & G_ELI_FLAG_GELIBOOT)) {
+		if (verbose)
+			printf("GELIBOOT flag not configured for %s.\n", prov);
+	} else if (geliboot >= 0) {
+		if (geliboot)
+			md.md_flags |= G_ELI_FLAG_GELIBOOT;
+		else
+			md.md_flags &= ~G_ELI_FLAG_GELIBOOT;
+		changed = 1;
+	}
+
 	if (trim == 0 && (md.md_flags & G_ELI_FLAG_NODELETE)) {
 		if (verbose)
 			printf("TRIM disable flag already configured for %s.\n", prov);
@@ -951,8 +971,8 @@ static void
 eli_configure(struct gctl_req *req)
 {
 	const char *prov;
-	bool boot, noboot, trim, notrim;
-	int doboot, dotrim;
+	bool boot, noboot, geliboot, nogeliboot, trim, notrim;
+	int doboot, dogeliboot, dotrim;
 	int i, nargs;
 
 	nargs = gctl_get_int(req, "nargs");
@@ -963,6 +983,8 @@ eli_configure(struct gctl_req *req)
 
 	boot = gctl_get_int(req, "boot");
 	noboot = gctl_get_int(req, "noboot");
+	geliboot = gctl_get_int(req, "geliboot");
+	nogeliboot = gctl_get_int(req, "nogeliboot");
 	trim = gctl_get_int(req, "trim");
 	notrim = gctl_get_int(req, "notrim");
 
@@ -976,6 +998,16 @@ eli_configure(struct gctl_req *req)
 	else if (noboot)
 		doboot = 0;
 
+	dogeliboot = -1;
+	if (geliboot && nogeliboot) {
+		gctl_error(req, "Options -g and -G are mutually exclusive.");
+		return;
+	}
+	if (geliboot)
+		dogeliboot = 1;
+	else if (nogeliboot)
+		dogeliboot = 0;
+
 	dotrim = -1;
 	if (trim && notrim) {
 		gctl_error(req, "Options -t and -T are mutually exclusive.");
@@ -986,7 +1018,7 @@ eli_configure(struct gctl_req *req)
 	else if (notrim)
 		dotrim = 0;
 
-	if (doboot == -1 && dotrim == -1) {
+	if (doboot == -1 && dogeliboot == -1 && dotrim == -1) {
 		gctl_error(req, "No option given.");
 		return;
 	}
@@ -997,7 +1029,7 @@ eli_configure(struct gctl_req *req)
 	for (i = 0; i < nargs; i++) {
 		prov = gctl_get_ascii(req, "arg%d", i);
 		if (!eli_is_attached(prov))
-			eli_configure_detached(req, prov, doboot, dotrim);
+			eli_configure_detached(req, prov, doboot, dogeliboot, dotrim);
 	}
 }