From 1860aac29624b1cb292a7ca549dc063bcd3f9bb6 Mon Sep 17 00:00:00 2001
From: Jeremy Kerr <jk@ozlabs.org>
Date: Wed, 30 Apr 2014 10:58:43 +0800
Subject: [PATCH 1/1] discover: check config.boot_device before setting a
 default

If a default device is set, we only allow booting from that device.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
---
 discover/device-handler.c     | 20 ++++++++++++++++++++
 discover/platform.c           |  1 +
 lib/pb-protocol/pb-protocol.c |  2 ++
 3 files changed, 23 insertions(+)

diff --git a/discover/device-handler.c b/discover/device-handler.c
index 7f7081d..b93cdfa 100644
--- a/discover/device-handler.c
+++ b/discover/device-handler.c
@@ -441,6 +441,22 @@ static int default_option_priority(struct discover_boot_option *opt)
 	return 0;
 }
 
+static bool device_allows_default(struct discover_device *dev)
+{
+	const char *dev_str;
+
+	dev_str = config_get()->boot_device;
+
+	if (!dev_str || !strlen(dev_str))
+		return true;
+
+	/* default devices are specified by UUIDs at present */
+	if (strcmp(dev->uuid, dev_str))
+		return false;
+
+	return true;
+}
+
 static void set_default(struct device_handler *handler,
 		struct discover_boot_option *opt)
 {
@@ -449,6 +465,10 @@ static void set_default(struct device_handler *handler,
 	if (!handler->autoboot_enabled)
 		return;
 
+	/* do we allow default-booting from this device? */
+	if (!device_allows_default(opt->device))
+		return;
+
 	new_prio = default_option_priority(opt);
 
 	/* A negative priority indicates that we don't want to boot this device
diff --git a/discover/platform.c b/discover/platform.c
index d745712..3ab6b7b 100644
--- a/discover/platform.c
+++ b/discover/platform.c
@@ -88,6 +88,7 @@ void config_set_defaults(struct config *config)
 	config->network.n_interfaces = 0;
 	config->network.dns_servers = NULL;
 	config->network.n_dns_servers = 0;
+	config->boot_device = NULL;
 
 	config->n_boot_priorities = 2;
 	config->boot_priorities = talloc_array(config, struct boot_priority,
diff --git a/lib/pb-protocol/pb-protocol.c b/lib/pb-protocol/pb-protocol.c
index 4a5c75a..67e1f9e 100644
--- a/lib/pb-protocol/pb-protocol.c
+++ b/lib/pb-protocol/pb-protocol.c
@@ -281,6 +281,8 @@ int pb_protocol_config_len(const struct config *config)
 	len += 4;
 	len += config->n_boot_priorities * 8;
 
+	len += 4 + optional_strlen(config->boot_device);
+
 	return len;
 }
 
-- 
2.39.2