1 files changed, 74 insertions, 0 deletions
diff --git a/lib/e2p/crypto_mode.c b/lib/e2p/crypto_mode.c
new file mode 100644
index 0000000..4933016
--- /dev/null
+++ b/lib/e2p/crypto_mode.c
@@ -0,0 +1,74 @@
+/*
+ * crypto_mode.c --- convert between encryption modes and strings
+ *
+ * Copyright (C) 1999  Theodore Ts'o <tytso@mit.edu>
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include "config.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <ctype.h>
+#include <errno.h>
+
+#include "e2p.h"
+
+struct mode {
+	int		num;
+	const char	*string;
+};
+
+static struct mode mode_list[] = {
+	{	EXT4_ENCRYPTION_MODE_INVALID,		"Invalid"},
+	{	EXT4_ENCRYPTION_MODE_AES_256_XTS,	"AES-256-XTS"},
+	{	EXT4_ENCRYPTION_MODE_AES_256_GCM,	"AES-256-GCM"},
+	{	EXT4_ENCRYPTION_MODE_AES_256_CBC,	"AES-256-CBC"},
+	{	0, 0 },
+};
+
+const char *e2p_encmode2string(int num)
+{
+	struct mode  *p;
+	static char buf[20];
+
+	for (p = mode_list; p->string; p++) {
+		if (num == p->num)
+			return p->string;
+	}
+	sprintf(buf, "ENC_MODE_%d", num);
+	return buf;
+}
+
+/*
+ * Returns the hash algorithm, or -1 on error
+ */
+int e2p_string2encmode(char *string)
+{
+	struct mode	*p;
+	char		*eptr;
+	int		num;
+
+	for (p = mode_list; p->string; p++) {
+		if (!strcasecmp(string, p->string)) {
+			return p->num;
+		}
+	}
+	if (strncasecmp(string, "ENC_MODE_", 9))
+		return -1;
+
+	if (string[9] == 0)
+		return -1;
+	num = strtol(string+9, &eptr, 10);
+	if (num > 255 || num < 0)
+		return -1;
+	if (*eptr)
+		return -1;
+	return num;
+}
+