X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=secnet.git;a=blobdiff_plain;f=transform-common.h;h=eea03c6be68b6c20f9fcfe5dcdb6e4db3ab42abb;hp=24ab8dc2bd54f042f79aaeeda920c968768378b3;hb=22c77971bb13c37344fc73fe9b8d72ed96181df2;hpb=3abd18e85781e00e2b7fc641f29c99e130238abf

diff --git a/transform-common.h b/transform-common.h
index 24ab8dc..eea03c6 100644
--- a/transform-common.h
+++ b/transform-common.h
@@ -11,20 +11,48 @@
 	}					\
     }while(0)
 
-#define SEQNUM_CHECK(seqnum, max_skew) do{	\
-	uint32_t skew=seqnum-ti->lastrecvseq;	\
-	if (skew<0x8fffffff) {			\
-	    /* Ok */				\
-	    ti->lastrecvseq=seqnum;		\
-	} else if ((0-skew)<max_skew) {	\
-	    /* Ok */				\
-	} else {				\
-	    /* Too much skew */			\
-	    *errmsg="seqnum: too much skew";	\
-	    return 2;				\
-	}					\
+#define RECVBITMAP_SIZE 32
+typedef uint32_t recvbitmap_type;
+
+#define SEQNUM_CHECK(seqnum, p) do{				\
+	uint32_t skew=seqnum-ti->lastrecvseq;			\
+	if (skew<0x8fffffff) {					\
+	    /* Ok */						\
+	    ti->lastrecvseq=seqnum;				\
+	    if (skew < RECVBITMAP_SIZE)				\
+                ti->recvbitmap <<= skew;			\
+            else						\
+                ti->recvbitmap=0;				\
+            skew=0;						\
+	} else if ((0-skew)<(p)->max_seq_skew) {		\
+	    /* Ok */						\
+	} else {						\
+	    /* Too much skew */					\
+	    *errmsg="seqnum: too much skew";			\
+	    return 2;						\
+	}							\
+	if ((p)->dedupe) {					\
+	    recvbitmap_type recvbit=(uint32_t)1 << skew;	\
+	    if (ti->recvbitmap & recvbit) {			\
+		*errmsg="seqnum: duplicate";			\
+		return 2;					\
+	    }							\
+	    ti->recvbitmap |= recvbit;				\
+	}							\
     }while(0)
 
+#define SEQNUM_KEYED_FIELDS						\
+    uint32_t sendseq;							\
+    uint32_t lastrecvseq;						\
+    recvbitmap_type recvbitmap; /* 1<<0 is lastrecvseq (i.e., most recent) */ \
+    bool_t keyed
+
+#define SEQNUM_KEYED_INIT(initlastrecvseq,initsendseq)	\
+    (ti->lastrecvseq=(initlastrecvseq),			\
+     ti->sendseq=(initsendseq),				\
+     ti->recvbitmap=0,					\
+     ti->keyed=True)
+
 #define TRANSFORM_VALID				\
     static bool_t transform_valid(void *sst)	\
     {						\
@@ -44,7 +72,7 @@
 
 #define SET_CAPAB_TRANSFORMNUM(def) do{					\
         st->ops.capab_transformnum=dict_read_number(dict, "capab-num",	\
-                                     False, "transform", loc, def);	\
+                                     False, "transform", loc, (def));	\
         if (st->ops.capab_transformnum > CAPAB_TRANSFORMNUM_MAX)	\
 	    cfgfatal(loc,"transform","capab-num out of range 0..%d\n",	\
 		     CAPAB_TRANSFORMNUM_MAX);				\
@@ -63,4 +91,19 @@
 	ti->ops.destroy=transform_destroy;		\
 	ti->keyed=False;
 
+#define SEQNUM_PARAMS_FIELDS			\
+    uint32_t max_seq_skew;			\
+    bool_t dedupe;
+
+#define SEQNUM_PARAMS_INIT(dict,p,desc,loc)				\
+    (p)->max_seq_skew=dict_read_number((dict), "max-sequence-skew",	\
+					False, (desc), (loc), 10);	\
+    bool_t can_dedupe=(p)->max_seq_skew < RECVBITMAP_SIZE;		\
+    (p)->dedupe=dict_read_bool((dict), "dedupe",			\
+			       False,(desc),(loc), can_dedupe);		\
+    if ((p)->dedupe && !can_dedupe)					\
+	cfgfatal(loc,"transform",					\
+                 "cannot dedupe with max-sequence-skew>=32");		\
+    else (void)0
+
 #endif /*TRANSFORM_COMMON_H*/