Rework the way transit provider AID masks are built and sent to the RDE.

ASPA provider AS sets can include optional limitations to inet/inet6 these
limits are represented in the TAS_AID bit masks (2bits per AS).
Introduce a TAS_AID_SIZE() makro that returns the size in bytes of this
bit mask (rounded to the next uint32_t).
Without this change aspa objects with AID specific elements trigger a
fatal error condition when the config is loaded.
OK tb@ job@

4 files changed, 31 insertions, 19 deletions

diff --git a/usr.sbin/bgpd/bgpd.h b/usr.sbin/bgpd/bgpd.h
index d0dd9850f65..181746b7ac1 100644
--- a/usr.sbin/bgpd/bgpd.h
+++ b/usr.sbin/bgpd/bgpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bgpd.h,v 1.474 2023/04/20 12:53:27 claudio Exp $ */
+/*	$OpenBSD: bgpd.h,v 1.475 2023/04/20 15:44:45 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -1273,6 +1273,7 @@ struct aspa_set {
 	uint8_t				 *tas_aid;
 	RB_ENTRY(aspa_set)		 entry;
 };
+#define TAS_AID_SIZE(n)	(((n) + 15) / 16 * sizeof(uint32_t))
 
 struct aspa_prep {
 	size_t				datasize;
diff --git a/usr.sbin/bgpd/rde.c b/usr.sbin/bgpd/rde.c
index 1fecf6c5151..8d51ec20b12 100644
--- a/usr.sbin/bgpd/rde.c
+++ b/usr.sbin/bgpd/rde.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde.c,v 1.604 2023/04/20 12:53:27 claudio Exp $ */
+/*	$OpenBSD: rde.c,v 1.605 2023/04/20 15:44:45 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -1312,7 +1312,7 @@ rde_dispatch_imsg_rtr(struct imsgbuf *ibuf)
 			if (aspa == NULL)
 				fatalx("unexpected IMSG_RECONF_ASPA_TAS");
 			if (imsg.hdr.len - IMSG_HEADER_SIZE !=
-			     aspa->num * sizeof(uint32_t))
+			    aspa->num * sizeof(uint32_t))
 				fatalx("IMSG_RECONF_ASPA_TAS bad len");
 			aspa->tas = reallocarray(NULL, aspa->num,
 			    sizeof(uint32_t));
@@ -1325,12 +1325,13 @@ rde_dispatch_imsg_rtr(struct imsgbuf *ibuf)
 			if (aspa == NULL)
 				fatalx("unexpected IMSG_RECONF_ASPA_TAS_AID");
 			if (imsg.hdr.len - IMSG_HEADER_SIZE !=
-			     (aspa->num + 15) / 16)
+			    TAS_AID_SIZE(aspa->num))
 				fatalx("IMSG_RECONF_ASPA_TAS_AID bad len");
-			aspa->tas_aid = malloc((aspa->num + 15) / 16);
+			aspa->tas_aid = malloc(TAS_AID_SIZE(aspa->num));
 			if (aspa->tas_aid == NULL)
 				fatal("IMSG_RECONF_ASPA_TAS_AID");
-			memcpy(aspa->tas_aid, imsg.data, (aspa->num + 15) / 16);
+			memcpy(aspa->tas_aid, imsg.data,
+			    TAS_AID_SIZE(aspa->num));
 			break;
 		case IMSG_RECONF_ASPA_DONE:
 			if (aspa_new == NULL)
diff --git a/usr.sbin/bgpd/rde_aspa.c b/usr.sbin/bgpd/rde_aspa.c
index 10602b68be7..da1746adfe4 100644
--- a/usr.sbin/bgpd/rde_aspa.c
+++ b/usr.sbin/bgpd/rde_aspa.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rde_aspa.c,v 1.3 2023/01/24 11:28:41 claudio Exp $ */
+/*	$OpenBSD: rde_aspa.c,v 1.4 2023/04/20 15:44:45 claudio Exp $ */
 
 /*
  * Copyright (c) 2022 Claudio Jeker <claudio@openbsd.org>
@@ -445,12 +445,13 @@ aspa_add_set(struct rde_aspa *ra, uint32_t cas, const uint32_t *pas,
 	/* nobody in their right mind has per afi specific data */
 	if (pas_aid != NULL) {
 		/* 2 bits per entry rounded to next uint32_t */
-		if (ra->maxdata - ra->curdata < (pascnt * 2 + 31) / 32)
+		if (ra->maxdata - ra->curdata <
+		    TAS_AID_SIZE(pascnt) / sizeof(ra->data[0]))
 			fatalx("aspa set data overflow");
 
 		aspa->pas_aid = ra->data + ra->curdata;
-		for (i = 0; i < (pascnt * 2 + 31) / 32; i++)
-			ra->data[ra->curdata++] = pas_aid[i];
+		memcpy(aspa->pas_aid, pas_aid, TAS_AID_SIZE(pascnt));
+		ra->curdata += TAS_AID_SIZE(pascnt) / sizeof(ra->data[0]);
 	}
 }
 
diff --git a/usr.sbin/bgpd/rtr.c b/usr.sbin/bgpd/rtr.c
index 2c3b18cc9c7..e30d0c4a7b9 100644
--- a/usr.sbin/bgpd/rtr.c
+++ b/usr.sbin/bgpd/rtr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtr.c,v 1.13 2023/03/28 12:15:23 claudio Exp $ */
+/*	$OpenBSD: rtr.c,v 1.14 2023/04/20 15:44:45 claudio Exp $ */
 
 /*
  * Copyright (c) 2020 Claudio Jeker <claudio@openbsd.org>
@@ -506,10 +506,15 @@ static size_t
 rtr_aspa_set_prep(struct aspa_set *aspa)
 {
 	uint32_t i, mask = 0;
+	uint8_t *tas_aid;
 	int needafi = 0;
 	size_t s;
 
 	s = aspa->num * sizeof(uint32_t);
+
+	if ((tas_aid = malloc(TAS_AID_SIZE(aspa->num))) == NULL)
+		fatal("tas_aid alloc");
+
 	for (i = 0; i < aspa->num; i++) {
 		switch (aspa->tas_aid[i]) {
 		case AID_INET:
@@ -525,19 +530,23 @@ rtr_aspa_set_prep(struct aspa_set *aspa)
 			break;
 		}
 		if (i % 16 == 15) {
-			memcpy(aspa->tas_aid + (i / 16) * sizeof(mask), &mask,
+			memcpy(tas_aid + (i / 16) * sizeof(mask), &mask,
 			    sizeof(mask));
 			mask = 0;
 		}
 	}
 
+	free(aspa->tas_aid);
+	aspa->tas_aid = NULL;
+
 	if (!needafi) {
-		free(aspa->tas_aid);
-		aspa->tas_aid = NULL;
+		free(tas_aid);
 	} else {
-		memcpy(aspa->tas_aid + (aspa->num / 16) * sizeof(mask), &mask,
-		    sizeof(mask));
-		s += (aspa->num + 15) / 16;
+		if (aspa->num % 16 != 0)
+			memcpy(tas_aid + (aspa->num / 16) * sizeof(mask),
+			    &mask, sizeof(mask));
+		aspa->tas_aid = tas_aid;
+		s += TAS_AID_SIZE(aspa->num);
 	}
 
 	return s;
@@ -596,8 +605,8 @@ rtr_recalc(void)
 		imsg_compose(ibuf_rde, IMSG_RECONF_ASPA_TAS, 0, 0, -1,
 		    aspa->tas, aspa->num * sizeof(*aspa->tas));
 		if (aspa->tas_aid)
-			imsg_compose(ibuf_rde, IMSG_RECONF_ASPA_TAS, 0, 0, -1,
-			    aspa->tas_aid, (aspa->num + 15) / 16);
+			imsg_compose(ibuf_rde, IMSG_RECONF_ASPA_TAS_AID, 0, 0,
+			    -1, aspa->tas_aid, TAS_AID_SIZE(aspa->num));
 		imsg_compose(ibuf_rde, IMSG_RECONF_ASPA_DONE, 0, 0, -1,
 		    NULL, 0);
 	}