X-Git-Url: https://git.distorted.org.uk/~mdw/tripe/blobdiff_plain/d8b106a3c886e95f1ba58a989347be984aa7682e..c70a7c5cedab62209640b76f03d97c1876e38dc6:/server/tripe.h

diff --git a/server/tripe.h b/server/tripe.h
index 86d3779e..24cec434 100644
--- a/server/tripe.h
+++ b/server/tripe.h
@@ -158,32 +158,114 @@
 
 typedef struct keyset keyset;
 typedef struct algswitch algswitch;
+typedef struct admin admin;
 
-typedef struct bulkcrypto {
+typedef struct bulkalgs {
+  const struct bulkops *ops;
+} bulkalgs;
+
+typedef struct bulkctx {
+  const struct bulkops *ops;
+} bulkctx;
+
+typedef struct bulkchal {
+  const struct bulkops *ops;
+  size_t tagsz;
+} bulkchal;
+
+struct rawkey;
+
+typedef struct bulkops {
   const char *name;
-  unsigned prim;
-  int (*check)(const algswitch */*a*/, dstr */*e*/);
-  size_t (*overhead)(const algswitch */*a*/);
-  int (*encrypt)(keyset */*ks*/, unsigned /*ty*/, buf */*b*/, buf */*bb*/);
-  int (*decrypt)(keyset */*ks*/, unsigned /*ty*/,
+
+  bulkalgs *(*getalgs)(const algswitch */*asw*/, dstr */*e*/,
+		       key_file */*kf*/, key */*k*/);
+	/* Determine algorithms to use and return a @bulkalgs@ object
+	 * representing the decision.  On error, write tokens to @e@ and
+	 * return null.
+	 */
+
+  T( void (*tracealgs)(const bulkalgs */*a*/); )
+	/* Write trace information about the algorithm selection. */
+
+  int (*checkalgs)(bulkalgs */*a*/, const algswitch */*asw*/, dstr */*e*/);
+	/* Check that the algorithms in @a@ and @asw@ are acceptable.  On
+	 * error, write tokens to @e@ and return @-1@; otherwise return zero.
+	 */
+
+  int (*samealgsp)(const bulkalgs */*a*/, const bulkalgs */*aa*/);
+	/* If @a@ and @aa@ represent the same algorithm selection, return
+	 * nonzero; if not, return zero.
+	 */
+
+  void (*alginfo)(const bulkalgs */*a*/, admin */*adm*/);
+	/* Report on the algorithm selection to an admin client: call
+	 * @a_info@ with appropriate key-value pairs.
+	 */
+
+  size_t (*overhead)(const bulkalgs */*a*/);
+	/* Return the per-packet overhead of the bulk transform, in bytes. */
+
+  size_t (*expsz)(const bulkalgs */*a*/);
+	/* Return the total size limit for the bulk transform, in bytes,
+	 * after which the keys must no longer be used.
+	 */
+
+  bulkctx *(*genkeys)(const bulkalgs */*a*/, const struct rawkey */*rk*/);
+	/* Generate session keys and construct and return an appropriate
+	 * context for using them, by calling @ks_derive@.
+	 */
+
+  bulkchal *(*genchal)(const bulkalgs */*a*/);
+	/* Construct and return a challenge issuing and verification
+	 * context with a fresh random key.
+	 */
+
+  void (*freealgs)(bulkalgs */*a*/);
+	/* Release an algorithm selection object.  (Associated bulk
+	 * encryption contexts and challenge contexts may still exist and
+	 * must remain valid.)
+	 */
+
+  int (*encrypt)(bulkctx */*bc*/, unsigned /*ty*/,
+		 buf */*b*/, buf */*bb*/, uint32 /*seq*/);
+	/* Encrypt the packet in @b@, with type @ty@ (which doesn't need
+	 * encoding separately) and sequence number @seq@ (which must be
+	 * recoverable by @decrypt@), and write the result to @bb@.  On
+	 * error, return a @KSERR_...@ code and/or break the output buffer.
+	 */
+
+  int (*decrypt)(bulkctx */*bc*/, unsigned /*ty*/,
 		 buf */*b*/, buf */*bb*/, uint32 */*seq*/);
-} bulkcrypto;
+	/* Decrypt the packet in @b@, with type @ty@, writing the result to
+	 * @bb@ and storing the incoming (claimed) sequence number in @seq@.
+	 * On error, return a @KSERR_...@ code.
+	 */
+
+  void (*freectx)(bulkctx */*a*/);
+	/* Release a bulk encryption context and the resources it holds. */
+
+  int (*chaltag)(bulkchal */*bc*/, const void */*m*/, size_t /*msz*/,
+		 void */*t*/);
+	/* Calculate a tag for the challenge in @m@, @msz@, and write it to
+	 * @t@.  Return @-1@ on error, zero on success.
+	 */
 
-#define BCP_CIPHER 1
-#define BCP_MAC 2
-#define BCP_BLKC 4
+  int (*chalvrf)(bulkchal */*bc*/, const void */*m*/, size_t /*msz*/,
+		 const void */*t*/);
+	/* Check the tag @t@ on @m@, @msz@: return zero if the tag is OK,
+	 * nonzero if it's bad.
+	 */
+
+  void (*freechal)(bulkchal */*bc*/);
+	/* Release a challenge context and the resources it holds. */
+
+} bulkops;
 
 struct algswitch {
-  const gchash *h;			/* Hash function */
+  const gchash *h; size_t hashsz;	/* Hash function */
   const gccipher *mgf;			/* Mask-generation function */
-  const bulkcrypto *bulk;		/* Bulk crypto transformation */
-  const gccipher *c;			/* Symmetric encryption scheme */
-  const gcmac *m;			/* Message authentication code */
-  const gccipher *b;			/* Block cipher */
-  size_t hashsz;			/* Hash output size */
-  size_t tagsz;				/* Length to truncate MAC tags */
-  size_t expsz;				/* Size of data to process */
-  size_t cksz, mksz, bksz;		/* Key lengths for things */
+  bulkalgs *bulk;			/* Bulk crypto algorithms */
 };
 
 typedef struct kdata {
@@ -210,7 +292,7 @@ typedef struct knode {
 
 #define HASH_STRING(h, s) GH_HASH((h), (s), sizeof(s))
 
-extern const bulkcrypto bulktab[];
+extern const bulkops bulktab[];
 
 /*----- Data structures ---------------------------------------------------*/
 
@@ -258,6 +340,8 @@ typedef struct seqwin {
  * expiry.
  */
 
+enum { DIR_IN, DIR_OUT, NDIR };
+
 struct keyset {
   struct keyset *next;			/* Next active keyset in the list */
   unsigned ref;				/* Reference count for keyset */
@@ -266,13 +350,7 @@ struct keyset {
   unsigned long sz_exp, sz_regen;	/* Data limits for the keyset */
   T( unsigned seq; )			/* Sequence number for tracing */
   unsigned f;				/* Various useful flags */
-  const bulkcrypto *bulk;		/* Bulk crypto transform */
-  size_t tagsz;				/* Length to truncate MAC tags */
-  struct ksdir {
-    gcipher *c;				/* Keyset cipher for encryption */
-    gmac *m;				/* Keyset MAC for integrity */
-    gcipher *b;				/* Block cipher, just in case */
-  } in, out;
+  bulkctx *bulk;			/* Bulk crypto transform */
   uint32 oseq;				/* Outbound sequence number */
   seqwin iseq;				/* Inbound sequence number */
 };
@@ -529,7 +607,7 @@ typedef struct admin_jobtable {
   admin_jobentry *v;			/* And the big array of entries */
 } admin_jobtable;
 
-typedef struct admin {
+struct admin {
   struct admin *next, *prev;		/* Links to next and previous */
   unsigned f;				/* Various useful flags */
   unsigned ref;				/* Reference counter */
@@ -543,7 +621,7 @@ typedef struct admin {
   admin_jobtable j;			/* Table of outstanding jobs */
   selbuf b;				/* Line buffer for commands */
   sel_file w;				/* Selector for write buffering */
-} admin;
+};
 
 #define AF_DEAD 1u			/* Destroy this admin block */
 #define AF_CLOSE 2u			/* Client closed connection */
@@ -748,6 +826,27 @@ extern int kx_init(keyexch */*kx*/, peer */*p*/,
 
 extern void ks_drop(keyset */*ks*/);
 
+/* --- @ks_derivekey@ --- *
+ *
+ * Arguments:	@octet *k@ = pointer to an output buffer of at least
+ *			@MAXHASHSZ@ bytes
+ *		@size_t ksz@ = actual size wanted (for tracing)
+ *		@const struct rawkey *rk@ = a raw key, as passed into
+ *			@genkeys@
+ *		@int dir@ = direction for the key (@DIR_IN@ or @DIR_OUT@)
+ *		@const char *what@ = label for the key (input to derivation)
+ *
+ * Returns:	---
+ *
+ * Use:		Derives a session key, for use on incoming or outgoing data.
+ *		This function is part of a private protocol between @ks_gen@
+ *		and the bulk crypto transform @genkeys@ operation.
+ */
+
+extern void ks_derivekey(octet */*k*/, size_t /*ksz*/,
+			 const struct rawkey */*rk*/,
+			 int /*dir*/, const char */*what*/);
+
 /* --- @ks_gen@ --- *
  *
  * Arguments:	@const void *k@ = pointer to key material
@@ -980,6 +1079,19 @@ extern void a_vformat(dstr */*d*/, const char */*fmt*/, va_list */*ap*/);
 
 extern void EXECL_LIKE(0) a_format(dstr */*d*/, const char */*fmt*/, ...);
 
+/* --- @a_info@ --- *
+ *
+ * Arguments:	@admin *a@ = connection
+ *		@const char *fmt@ = format string
+ *		@...@ = other arguments
+ *
+ * Returns:	---
+ *
+ * Use:		Report information to an admin client.
+ */
+
+extern void EXECL_LIKE(0) a_info(admin */*a*/, const char */*fmt*/, ...);
+
 /* --- @a_warn@ --- *
  *
  * Arguments:	@const char *fmt@ = pointer to format string