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Diffstat (limited to 'src/pluto/alg/ike_alg_serpent.c')
-rw-r--r--src/pluto/alg/ike_alg_serpent.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/src/pluto/alg/ike_alg_serpent.c b/src/pluto/alg/ike_alg_serpent.c
new file mode 100644
index 000000000..fb01caa41
--- /dev/null
+++ b/src/pluto/alg/ike_alg_serpent.c
@@ -0,0 +1,70 @@
+#include <stdio.h>
+#include <string.h>
+#include <stddef.h>
+#include <sys/types.h>
+#include <freeswan.h>
+
+#include "constants.h"
+#include "defs.h"
+#include "log.h"
+#include "libserpent/serpent_cbc.h"
+#include "alg_info.h"
+#include "ike_alg.h"
+
+#define SERPENT_CBC_BLOCK_SIZE (128/BITS_PER_BYTE)
+#define SERPENT_KEY_MIN_LEN 128
+#define SERPENT_KEY_DEF_LEN 128
+#define SERPENT_KEY_MAX_LEN 256
+
+static void
+do_serpent(u_int8_t *buf, size_t buf_size, u_int8_t *key, size_t key_size, u_int8_t *iv, bool enc)
+{
+ serpent_context serpent_ctx;
+ char iv_bak[SERPENT_CBC_BLOCK_SIZE];
+ char *new_iv = NULL; /* logic will avoid copy to NULL */
+
+
+ serpent_set_key(&serpent_ctx, key, key_size);
+ /*
+ * my SERPENT cbc does not touch passed IV (optimization for
+ * ESP handling), so I must "emulate" des-like IV
+ * crunching
+ */
+ if (!enc)
+ memcpy(new_iv=iv_bak,
+ (char*) buf + buf_size-SERPENT_CBC_BLOCK_SIZE,
+ SERPENT_CBC_BLOCK_SIZE);
+
+ serpent_cbc_encrypt(&serpent_ctx, buf, buf, buf_size, iv, enc);
+
+ if (enc)
+ new_iv = (char*) buf + buf_size-SERPENT_CBC_BLOCK_SIZE;
+
+ memcpy(iv, new_iv, SERPENT_CBC_BLOCK_SIZE);
+}
+
+struct encrypt_desc encrypt_desc_serpent =
+{
+ algo_type: IKE_ALG_ENCRYPT,
+ algo_id: OAKLEY_SERPENT_CBC,
+ algo_next: NULL,
+ enc_ctxsize: sizeof(struct serpent_context),
+ enc_blocksize: SERPENT_CBC_BLOCK_SIZE,
+ keyminlen: SERPENT_KEY_MIN_LEN,
+ keydeflen: SERPENT_KEY_DEF_LEN,
+ keymaxlen: SERPENT_KEY_MAX_LEN,
+ do_crypt: do_serpent,
+};
+
+int ike_alg_serpent_init(void);
+
+int
+ike_alg_serpent_init(void)
+{
+ int ret = ike_alg_register_enc(&encrypt_desc_serpent);
+
+ return ret;
+}
+/*
+IKE_ALG_INIT_NAME: ike_alg_serpent_init
+*/