From 192841962559a43b871ac7731b791e4916659ea7 Mon Sep 17 00:00:00 2001
From: Alexandre Snarskii <snar@snar.spb.ru>
Date: Wed, 11 May 2016 11:33:16 +0300
Subject: [PATCH] IOS XR as-path-sets

---
 CHANGES         |  5 ++-
 bgpq3.c         | 12 ++++++--
 bgpq3_printer.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 94 insertions(+), 4 deletions(-)

diff --git a/CHANGES b/CHANGES
index fc4c50c..8846c84 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,4 +1,7 @@
-untagged yet (2015-09-23)
+untagged yet (2016-05-10)
+    - feature: IOS XR mode now supports as-paths (ios-regexs). Thanks
+      to Tassos Chatzithomaoglou for examples and proofreading.
+    (additions from 2015-09-23)
     - bugfix: stoplist shall be able to catch AS numbers as promised.
     - bugfix: bgpq3 shall not hang at unknown escapes in -M..
     - gotcha: "ANY" object in recursive mode ignored: shut complaints on
diff --git a/bgpq3.c b/bgpq3.c
index b599bbb..4c1e101 100644
--- a/bgpq3.c
+++ b/bgpq3.c
@@ -305,6 +305,8 @@ main(int argc, char* argv[])
 		if(expander.generation==T_ASPATH) {
 			if(expander.vendor==V_CISCO) {
 				expander.aswidth=4;
+			} else if(expander.vendor==V_CISCO_XR) {
+				expander.aswidth=6;
 			} else if(expander.vendor==V_JUNIPER) {
 				expander.aswidth=8;
 			} else if(expander.vendor==V_BIRD) {
@@ -313,6 +315,8 @@ main(int argc, char* argv[])
 		} else if(expander.generation==T_OASPATH) {
 			if(expander.vendor==V_CISCO) {
 				expander.aswidth=5;
+			} else if(expander.vendor==V_CISCO_XR) {
+				expander.aswidth=7;
 			} else if(expander.vendor==V_JUNIPER) {
 				expander.aswidth=8;
 			};
@@ -323,8 +327,10 @@ main(int argc, char* argv[])
 		expander.generation=T_PREFIXLIST;
 	};
 
-	if(expander.vendor==V_CISCO_XR && expander.generation!=T_PREFIXLIST) {
-		sx_report(SX_FATAL, "Sorry, only prefix-sets supported for IOS XR\n");
+	if(expander.vendor==V_CISCO_XR && expander.generation!=T_PREFIXLIST &&
+		expander.generation!=T_ASPATH && expander.generation!=T_OASPATH) {
+		sx_report(SX_FATAL, "Sorry, only prefix-sets and as-paths "
+			"supported for IOS XR\n");
 	};
 	if(expander.vendor==V_BIRD && expander.generation!=T_PREFIXLIST &&
 		expander.generation!=T_ASPATH) {
@@ -536,4 +542,4 @@ main(int argc, char* argv[])
 
 	return 0;
 };
-			
+
diff --git a/bgpq3_printer.c b/bgpq3_printer.c
index 5b4618d..670e474 100644
--- a/bgpq3_printer.c
+++ b/bgpq3_printer.c
@@ -80,6 +80,45 @@ bgpq3_print_cisco_aspath(FILE* f, struct bgpq_expander* b)
 		fprintf(f,"ip as-path access-list %s deny .*\n", b->name?b->name:"NN");
 	return 0;
 };
+
+int
+bgpq3_print_cisco_xr_aspath(FILE* f, struct bgpq_expander* b)
+{
+	int nc=0, i, j, k, comma=0;
+	fprintf(f, "as-path-set %s", b->name?b->name:"NN");
+	if(b->asn32s[b->asnumber/65536] &&
+		b->asn32s[b->asnumber/65536][(b->asnumber%65536)/8]&
+		(0x80>>(b->asnumber%8))) {
+		fprintf(f,"\n  ios-regex '^%u(_%u)*$'", b->asnumber,b->asnumber);
+		comma=1;
+	};
+	for(k=0;k<65536;k++) {
+		if(!b->asn32s[k]) continue;
+
+		for(i=0;i<8192;i++) {
+			for(j=0;j<8;j++) {
+				if(b->asn32s[k][i]&(0x80>>j)) {
+					if(k*65536+i*8+j==b->asnumber) continue;
+					if(!nc) {
+						fprintf(f,"%s\n  ios-regex '^%u(_[0-9]+)*_(%u",
+							comma?",":"", b->asnumber,k*65536+i*8+j);
+						comma=1;
+					} else {
+						fprintf(f,"|%u",k*65536+i*8+j);
+					}
+					nc++;
+					if(nc==b->aswidth) {
+						fprintf(f,")$'");
+						nc=0;
+					};
+				};
+			};
+		};
+	};
+	if(nc) fprintf(f,")$'");
+	fprintf(f,"\nend-set\n");
+	return 0;
+};
 int
 bgpq3_print_cisco_oaspath(FILE* f, struct bgpq_expander* b)
 {
@@ -138,6 +177,44 @@ bgpq3_print_cisco_oaspath(FILE* f, struct bgpq_expander* b)
 		fprintf(f,"ip as-path access-list %s deny .*\n", b->name?b->name:"NN");
 	return 0;
 };
+
+int
+bgpq3_print_cisco_xr_oaspath(FILE* f, struct bgpq_expander* b)
+{
+	int nc=0, i, j, k, comma=0;
+	fprintf(f, "as-path-set %s", b->name?b->name:"NN");
+	if(b->asn32s[b->asnumber/65536] &&
+		b->asn32s[b->asnumber/65536][(b->asnumber%65536)/8]&
+			(0x80>>(b->asnumber%8))) {
+		fprintf(f,"\n  ios-regex '^(_%u)*$'",b->asnumber);
+		comma=1;
+	};
+	for(k=0;k<65536;k++) {
+		if(!b->asn32s[k]) continue;
+		for(i=0;i<8192;i++) {
+			for(j=0;j<8;j++) {
+				if(b->asn32s[k][i]&(0x80>>j)) {
+					if(k*65536+i*8+j==b->asnumber) continue;
+					if(!nc) {
+						fprintf(f,"%s\n  ios-regex '^(_[0-9]+)*_(%u",
+							comma?",":"", k*65536+i*8+j);
+						comma=1;
+					} else {
+						fprintf(f,"|%u",k*65536+i*8+j);
+					}
+					nc++;
+					if(nc==b->aswidth) {
+						fprintf(f,")$'");
+						nc=0;
+					};
+				};
+			};
+		};
+	};
+	if(nc) fprintf(f,")$'");
+	fprintf(f,"\nend-set\n");
+	return 0;
+};
 		
 int
 bgpq3_print_juniper_aspath(FILE* f, struct bgpq_expander* b)
@@ -233,6 +310,8 @@ bgpq3_print_aspath(FILE* f, struct bgpq_expander* b)
 		return bgpq3_print_juniper_aspath(f,b);
 	} else if(b->vendor==V_CISCO) {
 		return bgpq3_print_cisco_aspath(f,b);
+	} else if(b->vendor==V_CISCO_XR) {
+		return bgpq3_print_cisco_xr_aspath(f,b);
 	} else if(b->vendor==V_JSON) {
 		return bgpq3_print_json_aspath(f,b);
 	} else if(b->vendor==V_BIRD) {
@@ -250,6 +329,8 @@ bgpq3_print_oaspath(FILE* f, struct bgpq_expander* b)
 		return bgpq3_print_juniper_oaspath(f,b);
 	} else if(b->vendor==V_CISCO) {
 		return bgpq3_print_cisco_oaspath(f,b);
+	} else if(b->vendor==V_CISCO_XR) {
+		return bgpq3_print_cisco_xr_oaspath(f,b);
 	} else {
 		sx_report(SX_FATAL,"Unknown vendor %i\n", b->vendor);
 	};