[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>

/* 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
	14	/* boot_id depends on sysctl */
	15	#if defined(CONFIG_SYSCTL)
	16
	17	#include <wrapper/fs.h>
	18	#include <linux/file.h>
	19	#include <linux/sched.h>
	20	#include <linux/uaccess.h>
	21	#include <wrapper/random.h>
	22
	23	/*
	24	* Returns string boot id.
	25	*/
	26	int wrapper_get_bootid(char *bootid)
	27	{
	28	struct file *file;
	29	int ret;
	30	ssize_t len;
	31
	32	file = filp_open("/proc/sys/kernel/random/boot_id", O_RDONLY, 0);
	33	if (IS_ERR(file))
	34	return PTR_ERR(file);
	35
	36	len = lttng_kernel_read(file, bootid, BOOT_ID_LEN - 1, &file->f_pos);
	37	if (len != BOOT_ID_LEN - 1) {
	38	ret = -EINVAL;
	39	goto end;
	40	}
	41
	42	bootid[BOOT_ID_LEN - 1] = '\0';
	43	ret = 0;
	44	end:
	45	filp_close(file, current->files);
	46	return ret;
	47	}
	48	EXPORT_SYMBOL_GPL(wrapper_get_bootid);
	49
	50	#else
	51
	52	int wrapper_get_bootid(char *bootid)
	53	{
	54	return -ENOSYS;
	55	}
	56	EXPORT_SYMBOL_GPL(wrapper_get_bootid);
	57
	58	#endif