lib/check_signature.c

Source file repositories/reference/linux-study-clean/lib/check_signature.c

File Facts

System
Linux kernel
Corpus path
lib/check_signature.c
Extension
.c
Size
635 bytes
Lines
28
Domain
Kernel Services
Bucket
lib
Inferred role
Kernel Services: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
#include <linux/io.h>
#include <linux/export.h>

/**
 *	check_signature		-	find BIOS signatures
 *	@io_addr: mmio address to check
 *	@signature:  signature block
 *	@length: length of signature
 *
 *	Perform a signature comparison with the mmio address io_addr. This
 *	address should have been obtained by ioremap.
 *	Returns 1 on a match.
 */

int check_signature(const volatile void __iomem *io_addr,
			const unsigned char *signature, int length)
{
	while (length--) {
		if (readb(io_addr) != *signature)
			return 0;
		io_addr++;
		signature++;
	}
	return 1;
}
EXPORT_SYMBOL(check_signature);

Annotation

Implementation Notes