Files
qdl/sparse.c
Bjorn Andersson 29f623bd8c sparse: Clean up endianness and chunk type signedness
The sparse image format is defined in little endian, not in network
order, so we should not invoke ntohs()/ntohl() when reading them.
Further, the various constants are defined in host order, so we
shouldn't ntohs()/ntohl() them either.

This also implies that the code only works for little endian host
systems today.

Drop all the ntohs()/ntohl() conversions for now, to clean out the
incorrect conversions. The task to convert from little to host is left
as an exercise for the future.

While rewriting sparse_chunk_header_parse() the large if statement is
swapped for a select, to improve readability with a single successful
exit at the end and scattered exit returns throughout.

Fixes: 02c008adfd ("add support sparse attribute")
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
2025-08-28 10:42:08 -05:00

117 lines
3.0 KiB
C

// SPDX-License-Identifier: BSD-3-Clause
/*
* Copyright (c) 2025, Maksim Paimushkin <maxim.paymushkin.development@gmail.com>
* All rights reserved.
*/
#define _FILE_OFFSET_BITS 64
#ifdef _WIN32
#include <winsock2.h>
#else
#include <arpa/inet.h>
#endif
#include <ctype.h>
#include <errno.h>
#include <inttypes.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "sparse.h"
#include "qdl.h"
int sparse_header_parse(int fd, sparse_header_t *sparse_header)
{
lseek(fd, 0, SEEK_SET);
if (read(fd, sparse_header, sizeof(sparse_header_t)) != sizeof(sparse_header_t)) {
ux_err("[SPARSE] Unable to read sparse header\n");
return -EINVAL;
}
if (sparse_header->magic != SPARSE_HEADER_MAGIC) {
ux_err("[SPARSE] Invalid magic in sparse header\n");
return -EINVAL;
}
if (sparse_header->major_version != SPARSE_HEADER_MAJOR_VER) {
ux_err("[SPARSE] Invalid major version in sparse header\n");
return -EINVAL;
}
if (sparse_header->minor_version != SPARSE_HEADER_MINOR_VER) {
ux_err("[SPARSE] Invalid minor version in sparse header\n");
return -EINVAL;
}
if (sparse_header->file_hdr_sz > sizeof(sparse_header_t))
lseek(fd, sparse_header->file_hdr_sz - sizeof(sparse_header_t), SEEK_CUR);
return 0;
}
int sparse_chunk_header_parse(int fd, sparse_header_t *sparse_header,
uint64_t *chunk_size,
uint32_t *value,
off_t *offset)
{
chunk_header_t chunk_header;
uint32_t fill_value = 0;
unsigned int type;
*chunk_size = 0;
*value = 0;
if (read(fd, &chunk_header, sizeof(chunk_header_t)) != sizeof(chunk_header_t)) {
ux_err("[SPARSE] Unable to read sparse chunk header\n");
return -EINVAL;
}
if (sparse_header->chunk_hdr_sz > sizeof(chunk_header_t))
lseek(fd, sparse_header->chunk_hdr_sz - sizeof(chunk_header_t), SEEK_CUR);
type = chunk_header.chunk_type;
*chunk_size = (uint64_t)chunk_header.chunk_sz * sparse_header->blk_sz;
switch (type) {
case CHUNK_TYPE_RAW:
if (chunk_header.total_sz != (sparse_header->chunk_hdr_sz + *chunk_size)) {
ux_err("[SPARSE] Bogus chunk size, type Raw\n");
return -EINVAL;
}
/* Save the current file offset in the 'value' variable */
*offset = lseek(fd, 0, SEEK_CUR);
/* Move the file cursor forward by the size of the chunk */
lseek(fd, *chunk_size, SEEK_CUR);
break;
case CHUNK_TYPE_DONT_CARE:
if (chunk_header.total_sz != sparse_header->chunk_hdr_sz) {
ux_err("[SPARSE] Bogus chunk size, type Don't Care\n");
return -EINVAL;
}
break;
case CHUNK_TYPE_FILL:
if (chunk_header.total_sz != (sparse_header->chunk_hdr_sz + sizeof(fill_value))) {
ux_err("[SPARSE] Bogus chunk size, type Fill\n");
return -EINVAL;
}
if (read(fd, &fill_value, sizeof(fill_value)) != sizeof(fill_value)) {
ux_err("[SPARSE] Unable to read fill value\n");
return -EINVAL;
}
/* Save the current fill value in the 'value' variable */
*value = fill_value;
break;
default:
ux_err("[SPARSE] Unknown chunk type: %#x\n", type);
return -EINVAL;
}
return type;
}