1 files changed, 90 insertions, 0 deletions
diff --git a/src/lib/crypto/builtin/aes/aes_s2k.c b/src/lib/crypto/builtin/aes/aes_s2k.c
new file mode 100644
index 0000000..36045ed
--- /dev/null
+++ b/src/lib/crypto/builtin/aes/aes_s2k.c
@@ -0,0 +1,90 @@
+/*
+ * lib/crypto/aes/aes_s2k.c
+ *
+ * Copyright 2003 by the Massachusetts Institute of Technology.
+ * All Rights Reserved.
+ *
+ * Export of this software from the United States of America may
+ *   require a specific license from the United States Government.
+ *   It is the responsibility of any person or organization contemplating
+ *   export to obtain such a license before exporting.
+ * 
+ * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
+ * distribute this software and its documentation for any purpose and
+ * without fee is hereby granted, provided that the above copyright
+ * notice appear in all copies and that both that copyright notice and
+ * this permission notice appear in supporting documentation, and that
+ * the name of M.I.T. not be used in advertising or publicity pertaining
+ * to distribution of the software without specific, written prior
+ * permission.  Furthermore if you modify this software you must label
+ * your software as modified software and not distribute it in such a
+ * fashion that it might be confused with the original M.I.T. software.
+ * M.I.T. makes no representations about the suitability of
+ * this software for any purpose.  It is provided "as is" without express
+ * or implied warranty.
+ * 
+ *
+ * krb5int_aes_string_to_key
+ */
+
+#include "k5-int.h"
+#include "dk.h"
+#include "aes_s2k.h"
+
+#define DEFAULT_ITERATION_COUNT		4096 /* was 0xb000L in earlier drafts */
+#define MAX_ITERATION_COUNT		0x1000000L
+
+krb5_error_code
+krb5int_aes_string_to_key(const struct krb5_enc_provider *enc,
+			  const krb5_data *string,
+			  const krb5_data *salt,
+			  const krb5_data *params,
+			  krb5_keyblock *key)
+{
+    unsigned long iter_count;
+    krb5_data out;
+    static const krb5_data usage = { KV5M_DATA, 8, "kerberos" };
+    krb5_error_code err;
+
+    if (params) {
+	unsigned char *p = (unsigned char *) params->data;
+	if (params->length != 4)
+	    return KRB5_ERR_BAD_S2K_PARAMS;
+	/* The first two need casts in case 'int' is 16 bits.  */
+	iter_count = load_32_be(p);
+	if (iter_count == 0) {
+	    iter_count = (1UL << 16) << 16;
+	    if (((iter_count >> 16) >> 16) != 1)
+		return KRB5_ERR_BAD_S2K_PARAMS;
+	}
+    } else
+	iter_count = DEFAULT_ITERATION_COUNT;
+
+    /* This is not a protocol specification constraint; this is an
+       implementation limit, which should eventually be controlled by
+       a config file.  */
+    if (iter_count >= MAX_ITERATION_COUNT)
+	return KRB5_ERR_BAD_S2K_PARAMS;
+
+    /*
+     * Dense key space, no parity bits or anything, so take a shortcut
+     * and use the key contents buffer for the generated bytes.
+     */
+    out.data = (char *) key->contents;
+    out.length = key->length;
+    if (out.length != 16 && out.length != 32)
+	return KRB5_CRYPTO_INTERNAL;
+
+    err = krb5int_pbkdf2_hmac_sha1 (&out, iter_count, string, salt);
+    if (err) {
+	memset(out.data, 0, out.length);
+	return err;
+    }
+
+    err = krb5_derive_key (enc, key, key, &usage);
+    if (err) {
+	memset(out.data, 0, out.length);
+	return err;
+    }
+    return 0;
+}