coreboot-kgpe-d16/util/nvramtool/cbfs.c

136 lines
3.1 KiB
C

/* This file is part of the coreboot project. */
/* SPDX-License-Identifier: GPL-2.0-only */
#ifdef __MINGW32__
#include <winsock.h>
#else
#include <arpa/inet.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#ifndef __MINGW32__
#include <sys/mman.h>
#endif
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <stdio.h>
#include "cbfs.h"
#include "common.h"
#define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)
#define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
static void *cbfs_mapped;
static void *cbfs_offset;
static void* virt_to_phys(u32 virt)
{
return cbfs_offset + virt;
}
#ifdef DEBUG
#define debug(x...) printf(x)
#else
#define debug(x...) while(0) {}
#endif
static int cbfs_check_magic(struct cbfs_file *file)
{
return !strcmp(file->magic, CBFS_FILE_MAGIC) ? 1 : 0;
}
static struct cbfs_header *cbfs_master_header(void)
{
struct cbfs_header *header;
void *ptr = virt_to_phys(*((u32*)virt_to_phys(CBFS_HEADPTR_ADDR)));
debug("Check CBFS header at %p\n", ptr);
header = (struct cbfs_header *) ptr;
debug("magic is %08x\n", ntohl(header->magic));
if (ntohl(header->magic) != CBFS_HEADER_MAGIC) {
printf("ERROR: No valid CBFS header found!\n");
return NULL;
}
debug("Found CBFS header at %p\n", ptr);
return header;
}
struct cbfs_file *cbfs_find(const char *name)
{
struct cbfs_header *header = cbfs_master_header();
void *offset;
if (header == NULL)
return NULL;
offset = virt_to_phys(0 - ntohl(header->romsize) + ntohl(header->offset));
int align= ntohl(header->align);
while(1) {
struct cbfs_file *file = (struct cbfs_file *) offset;
if (!cbfs_check_magic(file)) return NULL;
debug("Check %s\n", CBFS_NAME(file));
if (!strcmp(CBFS_NAME(file), name))
return file;
int flen = ntohl(file->len);
int foffset = ntohl(file->offset);
debug("CBFS: follow chain: %p + %x + %x + align -> ", offset, foffset, flen);
void *oldoffset = offset;
offset = (void*)ALIGN((uintptr_t)(offset + foffset + flen), align);
debug("%p\n", (void *)offset);
if (offset <= oldoffset) return NULL;
if (offset < virt_to_phys(0xFFFFFFFF - ntohl(header->romsize)))
return NULL;
}
}
void *cbfs_find_file(const char *name, unsigned int type, unsigned int *len)
{
struct cbfs_file *file = cbfs_find(name);
if (file == NULL) {
printf("CBFS: Could not find file %s\n",
name);
return NULL;
}
if (ntohl(file->type) != type) {
printf("CBFS: File %s is of type %x instead of"
"type %x\n", name, file->type, type);
return NULL;
}
if (len != NULL) *len = file->len;
return (void *) CBFS_SUBHEADER(file);
}
void open_cbfs(const char *filename)
{
struct stat cbfs_stat;
int cbfs_fd;
cbfs_fd = open(filename, O_RDWR);
if (cbfs_fd == -1) {
printf("Couldn't open '%s'\n", filename);
exit(-1);
}
if (fstat(cbfs_fd, &cbfs_stat) == -1) {
printf("Couldn't stat '%s'\n", filename);
exit(-1);
}
cbfs_mapped = mmap(NULL, cbfs_stat.st_size, PROT_READ | PROT_WRITE,
MAP_SHARED, cbfs_fd, 0);
close(cbfs_fd);
if (cbfs_mapped == MAP_FAILED) {
printf("Couldn't map '%s'\n", filename);
exit(-1);
}
cbfs_offset = cbfs_mapped-(0xffffffff-cbfs_stat.st_size+1);
}