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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /lib/check_signature.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/check_signature.c')
-rw-r--r--lib/check_signature.c27
1 files changed, 27 insertions, 0 deletions
diff --git a/lib/check_signature.c b/lib/check_signature.c
new file mode 100644
index 000000000..43a7301da
--- /dev/null
+++ b/lib/check_signature.c
@@ -0,0 +1,27 @@
+// 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);