Index: crypto/cipher/null_cipher.c |
diff --git a/crypto/cipher/null_cipher.c b/crypto/cipher/null_cipher.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..4dc71afbe415aa1cae4874c6c3c7da6fc6acdbf5 |
--- /dev/null |
+++ b/crypto/cipher/null_cipher.c |
@@ -0,0 +1,156 @@ |
+/* |
+ * null_cipher.c |
+ * |
+ * A null cipher implementation. This cipher leaves the plaintext |
+ * unchanged. |
+ * |
+ * David A. McGrew |
+ * Cisco Systems, Inc. |
+ */ |
+ |
+/* |
+ * |
+ * Copyright (c) 2001-2006,2013 Cisco Systems, Inc. |
+ * All rights reserved. |
+ * |
+ * Redistribution and use in source and binary forms, with or without |
+ * modification, are permitted provided that the following conditions |
+ * are met: |
+ * |
+ * Redistributions of source code must retain the above copyright |
+ * notice, this list of conditions and the following disclaimer. |
+ * |
+ * 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. |
+ * |
+ * Neither the name of the Cisco Systems, Inc. nor the names of its |
+ * contributors may be used to endorse or promote products derived |
+ * from this software without specific prior written permission. |
+ * |
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 THE |
+ * COPYRIGHT HOLDERS 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. |
+ * |
+ */ |
+ |
+#ifdef HAVE_CONFIG_H |
+ #include <config.h> |
+#endif |
+ |
+#include "datatypes.h" |
+#include "null_cipher.h" |
+#include "err.h" /* for srtp_debug */ |
+#include "alloc.h" |
+ |
+/* the null_cipher uses the cipher debug module */ |
+ |
+extern srtp_debug_module_t srtp_mod_cipher; |
+ |
+static srtp_err_status_t srtp_null_cipher_alloc (srtp_cipher_t **c, int key_len, int tlen) |
+{ |
+ extern const srtp_cipher_type_t srtp_null_cipher; |
+ |
+ debug_print(srtp_mod_cipher, |
+ "allocating cipher with key length %d", key_len); |
+ |
+ /* allocate memory a cipher of type null_cipher */ |
+ *c = (srtp_cipher_t *)srtp_crypto_alloc(sizeof(srtp_cipher_t)); |
+ if (*c == NULL) { |
+ return srtp_err_status_alloc_fail; |
+ } |
+ memset(*c, 0x0, sizeof(srtp_cipher_t)); |
+ |
+ /* set pointers */ |
+ (*c)->algorithm = SRTP_NULL_CIPHER; |
+ (*c)->type = &srtp_null_cipher; |
+ (*c)->state = (void *) 0x1; /* The null cipher does not maintain state */ |
+ |
+ /* set key size */ |
+ (*c)->key_len = key_len; |
+ |
+ return srtp_err_status_ok; |
+ |
+} |
+ |
+static srtp_err_status_t srtp_null_cipher_dealloc (srtp_cipher_t *c) |
+{ |
+ extern const srtp_cipher_type_t srtp_null_cipher; |
+ |
+ /* zeroize entire state*/ |
+ octet_string_set_to_zero((uint8_t*)c, sizeof(srtp_cipher_t)); |
+ |
+ /* free memory of type null_cipher */ |
+ srtp_crypto_free(c); |
+ |
+ return srtp_err_status_ok; |
+ |
+} |
+ |
+static srtp_err_status_t srtp_null_cipher_init (void *cv, const uint8_t *key) |
+{ |
+ /* srtp_null_cipher_ctx_t *c = (srtp_null_cipher_ctx_t *)cv; */ |
+ |
+ debug_print(srtp_mod_cipher, "initializing null cipher", NULL); |
+ |
+ return srtp_err_status_ok; |
+} |
+ |
+static srtp_err_status_t srtp_null_cipher_set_iv (void *cv, uint8_t *iv, srtp_cipher_direction_t dir) |
+{ |
+ /* srtp_null_cipher_ctx_t *c = (srtp_null_cipher_ctx_t *)cv; */ |
+ return srtp_err_status_ok; |
+} |
+ |
+static srtp_err_status_t srtp_null_cipher_encrypt (void *cv, |
+ unsigned char *buf, unsigned int *bytes_to_encr) |
+{ |
+ /* srtp_null_cipher_ctx_t *c = (srtp_null_cipher_ctx_t *)cv; */ |
+ return srtp_err_status_ok; |
+} |
+ |
+static const char srtp_null_cipher_description[] = "null cipher"; |
+ |
+static const srtp_cipher_test_case_t srtp_null_cipher_test_0 = { |
+ 0, /* octets in key */ |
+ NULL, /* key */ |
+ 0, /* packet index */ |
+ 0, /* octets in plaintext */ |
+ NULL, /* plaintext */ |
+ 0, /* octets in plaintext */ |
+ NULL, /* ciphertext */ |
+ 0, |
+ NULL, |
+ 0, |
+ NULL /* pointer to next testcase */ |
+}; |
+ |
+ |
+/* |
+ * note: the decrypt function is idential to the encrypt function |
+ */ |
+ |
+const srtp_cipher_type_t srtp_null_cipher = { |
+ srtp_null_cipher_alloc, |
+ srtp_null_cipher_dealloc, |
+ srtp_null_cipher_init, |
+ 0, /* set_aad */ |
+ srtp_null_cipher_encrypt, |
+ srtp_null_cipher_encrypt, |
+ srtp_null_cipher_set_iv, |
+ 0, /* get_tag */ |
+ srtp_null_cipher_description, |
+ &srtp_null_cipher_test_0, |
+ SRTP_NULL_CIPHER |
+}; |
+ |