[lttng-modules.git] / wrapper / random.c

/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
 *
 * wrapper/random.c
 *
 * wrapper around bootid read. Using KALLSYMS to get its address when
 * available, else we need to have a kernel that exports this function to GPL
 * modules.
 *
 * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#include <linux/errno.h>
#include <linux/module.h>

/* boot_id depends on sysctl */
#if defined(CONFIG_SYSCTL)

#include <wrapper/fs.h>
#include <linux/file.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <wrapper/random.h>

/*
 * Returns string boot id.
 */
int wrapper_get_bootid(char *bootid)
{
	struct file *file;
	int ret;
	ssize_t len;

	file = filp_open("/proc/sys/kernel/random/boot_id", O_RDONLY, 0);
	if (IS_ERR(file))
		return PTR_ERR(file);

	len = lttng_kernel_read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
	if (len != BOOT_ID_LEN - 1) {
		ret = -EINVAL;
		goto end;
	}
	
	bootid[BOOT_ID_LEN - 1] = '\0';
	ret = 0;
end:
	filp_close(file, current->files);
	return ret;
}
EXPORT_SYMBOL_GPL(wrapper_get_bootid);

#else

int wrapper_get_bootid(char *bootid)
{
	return -ENOSYS;
}
EXPORT_SYMBOL_GPL(wrapper_get_bootid);

#endif
Commit	Line	Data
	1	/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
	2	*
	3	* wrapper/random.c
	4	*
	5	* wrapper around bootid read. Using KALLSYMS to get its address when
	6	* available, else we need to have a kernel that exports this function to GPL
	7	* modules.
	8	*
	9	* Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	10	*/
	11
	12	#include <linux/errno.h>
	13	#include <linux/module.h>
	14
	15	/* boot_id depends on sysctl */
	16	#if defined(CONFIG_SYSCTL)
	17
	18	#include <wrapper/fs.h>
	19	#include <linux/file.h>
	20	#include <linux/sched.h>
	21	#include <linux/uaccess.h>
	22	#include <wrapper/random.h>
	23
	24	/*
	25	* Returns string boot id.
	26	*/
	27	int wrapper_get_bootid(char *bootid)
	28	{
	29	struct file *file;
	30	int ret;
	31	ssize_t len;
	32
	33	file = filp_open("/proc/sys/kernel/random/boot_id", O_RDONLY, 0);
	34	if (IS_ERR(file))
	35	return PTR_ERR(file);
	36
	37	len = lttng_kernel_read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
	38	if (len != BOOT_ID_LEN - 1) {
	39	ret = -EINVAL;
	40	goto end;
	41	}
	42
	43	bootid[BOOT_ID_LEN - 1] = '\0';
	44	ret = 0;
	45	end:
	46	filp_close(file, current->files);
	47	return ret;
	48	}
	49	EXPORT_SYMBOL_GPL(wrapper_get_bootid);
	50
	51	#else
	52
	53	int wrapper_get_bootid(char *bootid)
	54	{
	55	return -ENOSYS;
	56	}
	57	EXPORT_SYMBOL_GPL(wrapper_get_bootid);
	58
	59	#endif