X-Git-Url: https://git.distorted.org.uk/~mdw/secnet/blobdiff_plain/9c6a8729f6553615786878b382d4d44d2a54eec0..refs/heads/mdw/xdh:/secnet.h

diff --git a/secnet.h b/secnet.h
index fe1f484..e54dbbe 100644
--- a/secnet.h
+++ b/secnet.h
@@ -350,10 +350,12 @@ extern init_module transform_cbcmac_module;
 extern init_module netlink_module;
 extern init_module rsa_module;
 extern init_module dh_module;
+extern init_module xdh_module;
 extern init_module md5_module;
 extern init_module slip_module;
 extern init_module tun_module;
 extern init_module sha1_module;
+extern init_module sha512_module;
 extern init_module log_module;
 
 /***** END of module support *****/
@@ -402,8 +404,8 @@ struct resolver_if {
 
 /* RANDOMSRC interface */
 
-/* Return some random data. Returns TRUE for success. */
-typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);
+/* Return some random data. Cannot fail. */
+typedef void random_fn(void *st, int32_t bytes, uint8_t *buff);
 
 struct random_if {
     void *st;
@@ -543,13 +545,24 @@ typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen,
 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);
-/* Returns:
- *   0: all is well
- *   1: for any other problem
- *   2: message decrypted but sequence number was out of range
- */
-typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
-				    const char **errmsg);
+
+typedef enum {
+    transform_apply_ok       = 0, /* all is well (everyone may assume==0) */
+    transform_apply_err      = 1, /* any other problem */
+    transform_apply_seqrange = 2,
+        /* message decrypted but sequence number was out of recent range */
+    transform_apply_seqdupe  = 3,
+        /* message decrypted but was dupe of recent packet */
+} transform_apply_return;
+
+static inline bool_t
+transform_apply_return_badseq(transform_apply_return problem) {
+    return problem == transform_apply_seqrange ||
+	   problem == transform_apply_seqdupe;
+}
+
+typedef transform_apply_return transform_apply_fn(void *st,
+        struct buffer_if *buf, const char **errmsg);
 
 struct transform_inst_if {
     void *st;
@@ -563,8 +576,7 @@ struct transform_inst_if {
 
 struct transform_if {
     void *st;
-    int capab_transformnum;
-    int32_t keylen; /* <<< INT_MAX */
+    int capab_bit;
     transform_createinstance_fn *create;
 };
 
@@ -600,17 +612,32 @@ struct netlink_if {
 
 /* DH interface */
 
-/* Returns public key as a malloced hex string */
-typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
-				  int32_t secretlen);
-/* Fills buffer (up to buflen) with shared secret */
-typedef void dh_makeshared_fn(void *st, uint8_t *secret,
-			      int32_t secretlen, cstring_t rempublic,
-			      uint8_t *sharedsecret, int32_t buflen);
+/* Write public value corresponding to the secret to the public buffer, and
+ * return its actual length.  The size of the buffer is given in publiclen,
+ * which will be at least the public_len reported by the closure.  The
+ * secretlen will be the secret_len reported by the closure.  This operation
+ * is not expected to fail.
+ */
+typedef int32_t dh_makepublic_fn(void *st, void *public, int32_t publiclen,
+				 uint8_t *secret, int32_t secretlen);
+
+/* Fills buffer (up to buflen) with shared secret.  The publiclen comes from
+ * the remote site, and may not be acceptable, though it has been checked for
+ * memory-safety.  The secretlen and buflen are the secret_len and shared_len
+ * reported by the closure, respectively.  Return false on faliure (e.g., if
+ * the publiclen is unacceptable).
+ */
+typedef bool_t dh_makeshared_fn(void *st,
+				uint8_t *secret, int32_t secretlen,
+				const void *public, int32_t publiclen,
+				uint8_t *sharedsecret, int32_t buflen);
+
 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 */
+    int32_t secret_len; /* Size of random secret to generate */
+    int32_t public_len; /* Maximum number of bytes needed for public value */
+    int32_t shared_len; /* Size of generated shared secret */
+    int capab_bit;
     dh_makepublic_fn *makepublic;
     dh_makeshared_fn *makeshared;
 };