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Diffstat (limited to 'hw/i386/pc_sysfw_ovmf.c')
-rw-r--r--hw/i386/pc_sysfw_ovmf.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/hw/i386/pc_sysfw_ovmf.c b/hw/i386/pc_sysfw_ovmf.c
new file mode 100644
index 0000000000..f4dd92c588
--- /dev/null
+++ b/hw/i386/pc_sysfw_ovmf.c
@@ -0,0 +1,151 @@
+/*
+ * QEMU PC System Firmware (OVMF specific)
+ *
+ * Copyright (c) 2003-2004 Fabrice Bellard
+ * Copyright (c) 2011-2012 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/i386/pc.h"
+#include "cpu.h"
+
+#define OVMF_TABLE_FOOTER_GUID "96b582de-1fb2-45f7-baea-a366c55a082d"
+
+static bool ovmf_flash_parsed;
+static uint8_t *ovmf_table;
+static int ovmf_table_len;
+
+void pc_system_parse_ovmf_flash(uint8_t *flash_ptr, size_t flash_size)
+{
+ uint8_t *ptr;
+ QemuUUID guid;
+ int tot_len;
+
+ /* should only be called once */
+ if (ovmf_flash_parsed) {
+ return;
+ }
+
+ ovmf_flash_parsed = true;
+
+ if (flash_size < TARGET_PAGE_SIZE) {
+ return;
+ }
+
+ /*
+ * if this is OVMF there will be a table footer
+ * guid 48 bytes before the end of the flash file. If it's
+ * not found, silently abort the flash parsing.
+ */
+ qemu_uuid_parse(OVMF_TABLE_FOOTER_GUID, &guid);
+ guid = qemu_uuid_bswap(guid); /* guids are LE */
+ ptr = flash_ptr + flash_size - 48;
+ if (!qemu_uuid_is_equal((QemuUUID *)ptr, &guid)) {
+ return;
+ }
+
+ /* if found, just before is two byte table length */
+ ptr -= sizeof(uint16_t);
+ tot_len = le16_to_cpu(*(uint16_t *)ptr) - sizeof(guid) - sizeof(uint16_t);
+
+ if (tot_len <= 0) {
+ return;
+ }
+
+ ovmf_table = g_malloc(tot_len);
+ ovmf_table_len = tot_len;
+
+ /*
+ * ptr is the foot of the table, so copy it all to the newly
+ * allocated ovmf_table and then set the ovmf_table pointer
+ * to the table foot
+ */
+ memcpy(ovmf_table, ptr - tot_len, tot_len);
+ ovmf_table += tot_len;
+}
+
+/**
+ * pc_system_ovmf_table_find - Find the data associated with an entry in OVMF's
+ * reset vector GUIDed table.
+ *
+ * @entry: GUID string of the entry to lookup
+ * @data: Filled with a pointer to the entry's value (if not NULL)
+ * @data_len: Filled with the length of the entry's value (if not NULL). Pass
+ * NULL here if the length of data is known.
+ *
+ * Return: true if the entry was found in the OVMF table; false otherwise.
+ */
+bool pc_system_ovmf_table_find(const char *entry, uint8_t **data,
+ int *data_len)
+{
+ uint8_t *ptr = ovmf_table;
+ int tot_len = ovmf_table_len;
+ QemuUUID entry_guid;
+
+ assert(ovmf_flash_parsed);
+
+ if (qemu_uuid_parse(entry, &entry_guid) < 0) {
+ return false;
+ }
+
+ if (!ptr) {
+ return false;
+ }
+
+ entry_guid = qemu_uuid_bswap(entry_guid); /* guids are LE */
+ while (tot_len >= sizeof(QemuUUID) + sizeof(uint16_t)) {
+ int len;
+ QemuUUID *guid;
+
+ /*
+ * The data structure is
+ * arbitrary length data
+ * 2 byte length of entire entry
+ * 16 byte guid
+ */
+ guid = (QemuUUID *)(ptr - sizeof(QemuUUID));
+ len = le16_to_cpu(*(uint16_t *)(ptr - sizeof(QemuUUID) -
+ sizeof(uint16_t)));
+
+ /*
+ * just in case the table is corrupt, wouldn't want to spin in
+ * the zero case
+ */
+ if (len < sizeof(QemuUUID) + sizeof(uint16_t)) {
+ return false;
+ } else if (len > tot_len) {
+ return false;
+ }
+
+ ptr -= len;
+ tot_len -= len;
+ if (qemu_uuid_is_equal(guid, &entry_guid)) {
+ if (data) {
+ *data = ptr;
+ }
+ if (data_len) {
+ *data_len = len - sizeof(QemuUUID) - sizeof(uint16_t);
+ }
+ return true;
+ }
+ }
+ return false;
+}