diff options
Diffstat (limited to 'src/pluto/alg/ike_alg_serpent.c')
-rw-r--r-- | src/pluto/alg/ike_alg_serpent.c | 70 |
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 +*/ |