1 files changed, 125 insertions, 0 deletions
diff --git a/src/lib/crypto/krb/crypto_length.c b/src/lib/crypto/krb/crypto_length.c
new file mode 100644
index 0000000000000..a621423a1e21a
--- /dev/null
+++ b/src/lib/crypto/krb/crypto_length.c
@@ -0,0 +1,125 @@
+/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+/* lib/crypto/krb/crypto_length.c */
+/*
+ * Copyright 2008 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.
+ */
+
+#include "crypto_int.h"
+
+krb5_error_code KRB5_CALLCONV
+krb5_c_crypto_length(krb5_context context, krb5_enctype enctype,
+                     krb5_cryptotype type, unsigned int *size)
+{
+    const struct krb5_keytypes *ktp;
+
+    ktp = find_enctype(enctype);
+    if (ktp == NULL)
+        return KRB5_BAD_ENCTYPE;
+
+    switch (type) {
+    case KRB5_CRYPTO_TYPE_EMPTY:
+    case KRB5_CRYPTO_TYPE_SIGN_ONLY:
+        *size = 0;
+        break;
+    case KRB5_CRYPTO_TYPE_DATA:
+        *size = (unsigned int)~0; /* match Heimdal */
+        break;
+    case KRB5_CRYPTO_TYPE_HEADER:
+    case KRB5_CRYPTO_TYPE_PADDING:
+    case KRB5_CRYPTO_TYPE_TRAILER:
+    case KRB5_CRYPTO_TYPE_CHECKSUM:
+        *size = ktp->crypto_length(ktp, type);
+        break;
+    default:
+        return EINVAL;
+    }
+
+    return 0;
+}
+
+krb5_error_code KRB5_CALLCONV
+krb5_c_padding_length(krb5_context context, krb5_enctype enctype,
+                      size_t data_length, unsigned int *pad_length)
+{
+    const struct krb5_keytypes *ktp;
+
+    ktp = find_enctype(enctype);
+    if (ktp == NULL)
+        return KRB5_BAD_ENCTYPE;
+
+    *pad_length = krb5int_c_padding_length(ktp, data_length);
+    return 0;
+}
+
+krb5_error_code KRB5_CALLCONV
+krb5_c_crypto_length_iov(krb5_context context, krb5_enctype enctype,
+                         krb5_crypto_iov *data, size_t num_data)
+{
+    size_t i;
+    const struct krb5_keytypes *ktp;
+    unsigned int data_length = 0, pad_length;
+    krb5_crypto_iov *padding = NULL;
+
+    /*
+     * XXX need to rejig internal interface so we can accurately
+     * report variable header lengths.
+     */
+
+    ktp = find_enctype(enctype);
+    if (ktp == NULL)
+        return KRB5_BAD_ENCTYPE;
+
+    for (i = 0; i < num_data; i++) {
+        krb5_crypto_iov *iov = &data[i];
+
+        switch (iov->flags) {
+        case KRB5_CRYPTO_TYPE_DATA:
+            data_length += iov->data.length;
+            break;
+        case KRB5_CRYPTO_TYPE_PADDING:
+            if (padding != NULL)
+                return EINVAL;
+
+            padding = iov;
+            break;
+        case KRB5_CRYPTO_TYPE_HEADER:
+        case KRB5_CRYPTO_TYPE_TRAILER:
+        case KRB5_CRYPTO_TYPE_CHECKSUM:
+            iov->data.length = ktp->crypto_length(ktp, iov->flags);
+            break;
+        case KRB5_CRYPTO_TYPE_EMPTY:
+        case KRB5_CRYPTO_TYPE_SIGN_ONLY:
+        default:
+            break;
+        }
+    }
+
+    pad_length = krb5int_c_padding_length(ktp, data_length);
+    if (pad_length != 0 && padding == NULL)
+        return EINVAL;
+
+    if (padding != NULL)
+        padding->data.length = pad_length;
+
+    return 0;
+}