1 files changed, 121 insertions, 0 deletions
diff --git a/src/lib/crypto/old/old_decrypt.c b/src/lib/crypto/old/old_decrypt.c
new file mode 100644
index 000000000..31fb6ce79
--- /dev/null
+++ b/src/lib/crypto/old/old_decrypt.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 1998 by the FundsXpress, INC.
+ * 
+ * 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 FundsXpress. not be used in advertising or publicity pertaining
+ * to distribution of the software without specific, written prior
+ * permission.  FundsXpress makes no representations about the suitability of
+ * this software for any purpose.  It is provided "as is" without express
+ * or implied warranty.
+ * 
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include "k5-int.h"
+#include "old.h"
+
+krb5_error_code
+krb5_old_decrypt(enc, hash, key, usage, ivec, input, arg_output)
+     krb5_const struct krb5_enc_provider *enc;
+     krb5_const struct krb5_hash_provider *hash;
+     krb5_const krb5_keyblock *key;
+     krb5_keyusage usage;
+     krb5_const krb5_data *ivec;
+     krb5_const krb5_data *input;
+     krb5_data *arg_output;
+{
+    krb5_error_code ret;
+    size_t blocksize, hashsize, plainsize;
+    unsigned char *plaintext, *cksumdata;
+    krb5_data output, cksum;
+    int alloced;
+
+    (*(enc->block_size))(&blocksize);
+    (*(hash->hash_size))(&hashsize);
+
+    plainsize = input->length - blocksize - hashsize;
+
+    if (arg_output->length < plainsize)
+	return(KRB5_BAD_MSIZE);
+
+    /* if there's enough space to work in the app buffer, use it,
+       otherwise allocate our own */
+
+    if ((cksumdata = (unsigned char *) malloc(hashsize)) == NULL)
+	return(ENOMEM);
+
+    if (arg_output->length < input->length) {
+	output.length = input->length;
+
+	if ((output.data = (krb5_octet *) malloc(output.length)) == NULL) {
+	    free(cksumdata);
+	    return(ENOMEM);
+	}
+
+	alloced = 1;
+    } else {
+	output.length = input->length;
+
+	output.data = arg_output->data;
+
+	alloced = 0;
+    }
+
+    /* decrypt it */
+
+    if (ret = ((*(enc->decrypt))(key, ivec, input, &output)))
+	goto cleanup;
+
+    /* verify the checksum */
+
+    memcpy(cksumdata, output.data+blocksize, hashsize);
+    memset(output.data+blocksize, 0, hashsize);
+
+    cksum.length = hashsize;
+    cksum.data = output.data+blocksize;
+
+    if (ret = ((*(hash->hash))(1, &output, &cksum)))
+	goto cleanup;
+
+    if (memcmp(cksum.data, output.data+blocksize, cksum.length) != 0) {
+	ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
+	goto cleanup;
+    }
+
+    /* copy the plaintext around */
+
+    if (alloced) {
+	memcpy(arg_output->data, output.data+blocksize+hashsize,
+	       plainsize);
+    } else {
+	memmove(arg_output->data, arg_output->data+blocksize+hashsize,
+		plainsize);
+    }
+    arg_output->length = plainsize;
+
+    ret = 0;
+
+cleanup:
+    if (alloced) {
+	memset(output.data, 0, output.length);
+	free(output.data);
+    }
+
+    memset(cksumdata, 0, hashsize);
+    free(cksumdata);
+    return(ret);
+}
+