kernel_read_file.h

 1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef _LINUX_KERNEL_READ_FILE_H
 3#define _LINUX_KERNEL_READ_FILE_H
 4
 5#include <linux/file.h>
 6#include <linux/types.h>
 7
 8/* This is a list of *what* is being read, not *how* nor *where*. */
 9#define __kernel_read_file_id(id) \
10	id(UNKNOWN, unknown)		\
11	id(FIRMWARE, firmware)		\
12	id(MODULE, kernel-module)		\
13	id(KEXEC_IMAGE, kexec-image)		\
14	id(KEXEC_INITRAMFS, kexec-initramfs)	\
15	id(POLICY, security-policy)		\
16	id(X509_CERTIFICATE, x509-certificate)	\
17	id(MODULE_COMPRESSED, kernel-module-compressed) \
18	id(MAX_ID, )
19
20#define __fid_enumify(ENUM, dummy) READING_ ## ENUM,
21#define __fid_stringify(dummy, str) #str,
22
23enum kernel_read_file_id {
24	__kernel_read_file_id(__fid_enumify)
25};
26
27static const char * const kernel_read_file_str[] = {
28	__kernel_read_file_id(__fid_stringify)
29};
30
31static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id)
32{
33	if ((unsigned int)id >= READING_MAX_ID)
34		return kernel_read_file_str[READING_UNKNOWN];
35
36	return kernel_read_file_str[id];
37}
38
39ssize_t kernel_read_file(struct file *file, loff_t offset,
40			 void **buf, size_t buf_size,
41			 size_t *file_size,
42			 enum kernel_read_file_id id);
43ssize_t kernel_read_file_from_path(const char *path, loff_t offset,
44				   void **buf, size_t buf_size,
45				   size_t *file_size,
46				   enum kernel_read_file_id id);
47ssize_t kernel_read_file_from_path_initns(const char *path, loff_t offset,
48					  void **buf, size_t buf_size,
49					  size_t *file_size,
50					  enum kernel_read_file_id id);
51ssize_t kernel_read_file_from_fd(int fd, loff_t offset,
52				 void **buf, size_t buf_size,
53				 size_t *file_size,
54				 enum kernel_read_file_id id);
55
56#endif /* _LINUX_KERNEL_READ_FILE_H */