site: support multiple transforms

[secnet.git] / secnet.h

diff --git a/secnet.h b/secnet.h
index 037ef804aec8f42e38355265be9508400251a16d..252eeb659b7f01fda5a8ba0b61e1788471195249 100644 (file)
--- a/secnet.h
+++ b/secnet.h
@@ -7,6 +7,8 @@
 #include <stdlib.h>
 #include <stdarg.h>
 #include <stdio.h>
+#include <string.h>
+#include <assert.h>
 #include <sys/poll.h>
 #include <sys/types.h>
 #include <sys/time.h>
@@ -217,7 +219,8 @@ extern init_module random_module;
 extern init_module udp_module;
 extern init_module util_module;
 extern init_module site_module;
-extern init_module transform_module;
+extern init_module transform_eax_module;
+extern init_module transform_cbcmac_module;
 extern init_module netlink_module;
 extern init_module rsa_module;
 extern init_module dh_module;
@@ -323,7 +326,6 @@ typedef const char *comm_addr_to_string_fn(void *commst,
 struct comm_if {
     void *st;
     int32_t min_start_pad;
-    int32_t min_end_pad;
     comm_request_notify_fn *request_notify;
     comm_release_notify_fn *release_notify;
     comm_sendmsg_fn *sendmsg;
@@ -361,17 +363,20 @@ struct site_if {
 /* TRANSFORM interface */
 
 /* A reversable transformation. Transforms buffer in-place; may add
-   data to start or end. Maximum amount of data to be added specified
-   in max_start_pad and max_end_pad. (Reverse transformations decrease
+   data to start or end. Maximum amount of data to be added before
+   the packet specified in max_start_pad. (Reverse transformations decrease
    length, of course.)  Transformations may be key-dependent, in which
    case key material is passed in at initialisation time. They may
    also depend on internal factors (eg. time) and keep internal
    state. A struct transform_if only represents a particular type of
    transformation; instances of the transformation (eg. with
-   particular key material) have a different C type. */
+   particular key material) have a different C type. The same
+   secret key will be used in opposite directions between a pair of
+   secnets; one of these pairs will get direction==False, the other True. */
 
 typedef struct transform_inst_if *transform_createinstance_fn(void *st);
-typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen);
+typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
+                                  bool_t direction);
 typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
 typedef void transform_delkey_fn(void *st);
 typedef void transform_destroyinstance_fn(void *st);
@@ -391,13 +396,14 @@ struct transform_inst_if {
     transform_apply_fn *forwards;
     transform_apply_fn *reverse;
     transform_destroyinstance_fn *destroy;
+    int32_t max_start_pad; /* same as from transform_if */
 };
 
 struct transform_if {
     void *st;
-    int32_t max_start_pad; /* these three are all <<< INT_MAX */
-    int32_t max_end_pad;
-    int32_t keylen;
+    int32_t max_start_pad; /* these two are both <<< INT_MAX */
+    int32_t keylen; /* 0 means give the transform exactly as much as there is */
+    int capab_transformnum;
     transform_createinstance_fn *create;
 };
 
@@ -419,8 +425,7 @@ typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
 #define MAXIMUM_LINK_QUALITY 3
 typedef void netlink_link_quality_fn(void *st, uint32_t quality);
 typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
-                                void *dst, int32_t max_start_pad,
-                                int32_t max_end_pad);
+                                void *dst, int32_t max_start_pad);
 typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
 typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
 typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
@@ -444,6 +449,7 @@ typedef void dh_makeshared_fn(void *st, uint8_t *secret,
 struct dh_if {
     void *st;
     int32_t len; /* Approximate size of modulus in bytes */
+    int32_t ceil_len; /* Number of bytes just sufficient to contain modulus */
     dh_makepublic_fn *makepublic;
     dh_makeshared_fn *makeshared;
 };