1 files changed, 138 insertions, 0 deletions
diff --git a/lib/libcrypt/crypt.c b/lib/libcrypt/crypt.c
new file mode 100644
index 000000000000..aaf3552f95ff
--- /dev/null
+++ b/lib/libcrypt/crypt.c
@@ -0,0 +1,138 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 1999 Mark Murray
+ * Copyright (c) 2014 Dag-Erling Smørgrav
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY MARK MURRAY AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL MARK MURRAY OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+
+#include <string.h>
+#include <unistd.h>
+
+#include "crypt.h"
+
+/*
+ * List of supported crypt(3) formats.
+ *
+ * The default algorithm is the last entry in the list (second-to-last
+ * array element since the last is a sentinel).  The reason for placing
+ * the default last rather than first is that DES needs to be at the
+ * bottom for the algorithm guessing logic in crypt(3) to work correctly,
+ * and it needs to be the default for backward compatibility.
+ */
+static const struct crypt_format {
+	const char *name;
+	int (*func)(const char *, const char *, char *);
+	const char *magic;
+} crypt_formats[] = {
+	{ "md5",	crypt_md5,		"$1$"	},
+#ifdef HAS_BLOWFISH
+	{ "blf",	crypt_blowfish,		"$2"	},
+#endif
+	{ "nth",	crypt_nthash,		"$3$"	},
+	{ "sha256",	crypt_sha256,		"$5$"	},
+	{ "sha512",	crypt_sha512,		"$6$"	},
+#ifdef HAS_DES
+	{ "des",	crypt_des,		"_"	},
+#endif
+
+	/* sentinel */
+	{ NULL,		NULL,			NULL	}
+};
+
+static const struct crypt_format *crypt_format =
+    &crypt_formats[(sizeof crypt_formats / sizeof *crypt_formats) - 2];
+
+#define DES_SALT_ALPHABET \
+	"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+
+/*
+ * Returns the name of the currently selected format.
+ */
+const char *
+crypt_get_format(void)
+{
+
+	return (crypt_format->name);
+}
+
+/*
+ * Selects the format to use for subsequent crypt(3) invocations.
+ */
+int
+crypt_set_format(const char *format)
+{
+	const struct crypt_format *cf;
+
+	for (cf = crypt_formats; cf->name != NULL; ++cf) {
+		if (strcasecmp(cf->name, format) == 0) {
+			crypt_format = cf;
+			return (1);
+		}
+	}
+	return (0);
+}
+
+/*
+ * Hash the given password with the given salt.  If the salt begins with a
+ * magic string (e.g. "$6$" for sha512), the corresponding format is used;
+ * otherwise, the currently selected format is used.
+ */
+char *
+crypt_r(const char *passwd, const char *salt, struct crypt_data *data)
+{
+	const struct crypt_format *cf;
+	int (*func)(const char *, const char *, char *);
+#ifdef HAS_DES
+	int len;
+#endif
+
+	for (cf = crypt_formats; cf->name != NULL; ++cf)
+		if (cf->magic != NULL && strstr(salt, cf->magic) == salt) {
+			func = cf->func;
+			goto match;
+		}
+#ifdef HAS_DES
+	len = strlen(salt);
+	if ((len == 13 || len == 2) && strspn(salt, DES_SALT_ALPHABET) == len) {
+		func = crypt_des;
+		goto match;
+	}
+#endif
+	func = crypt_format->func;
+match:
+	if (func(passwd, salt, data->__buf) != 0)
+		return (NULL);
+	return (data->__buf);
+}
+
+char *
+crypt(const char *passwd, const char *salt)
+{
+	static struct crypt_data data;
+
+	return (crypt_r(passwd, salt, &data));
+}