acrn-hypervisor/misc/efi-stub/multiboot.c

137 lines
4.7 KiB
C

/*
* Copyright (c) 2021, Intel Corporation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products
* derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <efi.h>
#include <efilib.h>
#include "boot.h"
#include "stdlib.h"
#include "multiboot.h"
/**
* @brief Search the first len bytes in buffer for multiboot1 header.
*
* @param[in] buffer Buffer to be searched
* @param[in] len Search length
*
* @return A pointer to the multiboot1 header if found. NULL otherwise.
*/
const struct multiboot_header *find_mb1header(const UINT8 *buffer, uint64_t len)
{
const struct multiboot_header *header;
for (header = (struct multiboot_header *)buffer;
((char *)header <= (char *)buffer + len - 12);
header = (struct multiboot_header *)((char *)header + MULTIBOOT_HEADER_ALIGN))
{
if (header->mh_magic == MULTIBOOT_HEADER_MAGIC &&
!(header->mh_magic + header->mh_flags + header->mh_checksum))
return header;
}
return NULL;
}
/**
* @brief Search the first len bytes in buffer for multiboot2 header.
*
* @param[in] buffer Buffer to be searched
* @param[in] len Search length
*
* @return A pointer to the multiboot2 header if found. NULL otherwise.
*/
const struct multiboot2_header *find_mb2header(const UINT8 *buffer, uint64_t len)
{
const struct multiboot2_header *header;
for (header = (const struct multiboot2_header *)buffer;
((char *)header <= (char *)buffer + len - 12);
header = (struct multiboot2_header *)((uint64_t)header + MULTIBOOT2_HEADER_ALIGN / 4))
{
if (header->magic == MULTIBOOT2_HEADER_MAGIC &&
!(header->magic + header->architecture + header->header_length + header->checksum) &&
header->architecture == MULTIBOOT2_ARCHITECTURE_I386)
return header;
}
return NULL;
}
/**
* @brief Parse the multiboot2 header and return a list of pointers to the header tags.
*
* @param[in] header Multiboot2 header to be parsed.
* @param[out] hv_tags An hv_mb2header_tag_list struct that contains pointers to all possible
* tags in a multiboot2 header. If a field in this struct is not NULL, it
* means the tag was found in the given header. NULL otherwise.
*
* @return 0 on success. -1 on error.
*/
int parse_mb2header(const struct multiboot2_header *header, struct hv_mb2header_tag_list *hv_tags)
{
struct multiboot2_header_tag *tag;
memset(hv_tags, 0, sizeof(struct hv_mb2header_tag_list));
for (tag = (struct multiboot2_header_tag *)(header + 1);
tag->type != MULTIBOOT2_TAG_TYPE_END;
tag = (struct multiboot2_header_tag *)((uint32_t *)tag + ALIGN_UP(tag->size, MULTIBOOT2_TAG_ALIGN) / 4))
{
switch (tag->type) {
case MULTIBOOT2_HEADER_TAG_INFORMATION_REQUEST:
/* Ignored. Currently we didn't support all categories of requested information,
* only the part that ACRN requests. So we don't parse the requests here. */
break;
case MULTIBOOT2_HEADER_TAG_ADDRESS:
hv_tags->addr = (struct multiboot2_header_tag_address *)tag;
break;
case MULTIBOOT2_HEADER_TAG_ENTRY_ADDRESS:
hv_tags->entry = (struct multiboot2_header_tag_entry_address *)tag;
break;
case MULTIBOOT2_HEADER_TAG_RELOCATABLE:
hv_tags->reloc = (struct multiboot2_header_tag_relocatable *)tag;
break;
default:
Print(L"Unsupported multiboot2 tag type: %d\n", tag->type);
return -1;
}
}
if (hv_tags->addr && !hv_tags->entry)
return -1;
return 0;
}