lib, bgp: add initial support for asdot format

AS number can be defined as an unsigned long number, or
two uint16 values separated by a period (.). The possible
valus are:
- usual 32 bit values : [1;2^32 -1]
- <1.65535>.<0.65535> for dot notation
- <0.65535>.<0.65535> for dot+ notation.

The 0.0 value is forbidden when configuring BGP instances
or peer configurations.

A new ASN type is added for parsing in the vty.
The following commands use that new identifier:
- router bgp ..
- bgp confederation ..
- neighbor <> remote-as <>
- neighbor <> local-as <>
- clear ip bgp <>
- route-map / set as-path <>

An asn library is available in lib/ and provides some
services:
- convert an as string into an as number.
- parse an as path list string and extract a number.
- convert an as number into a string.

Also, the bgp tests forge an as_zero_path, and to do that,
an API to relax the possibility to have a 0 as value is
specifically called from the tests.

Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/lib/command_lex.l b/lib/command_lex.l
index ec366ce7e1..60661b986d 100644
--- a/lib/command_lex.l
+++ b/lib/command_lex.l
@@ -54,6 +54,7 @@ VARIABLE        [A-Z][-_A-Z:0-9]+
 WORD            (\-|\+)?[a-zA-Z0-9\*][-+_a-zA-Z0-9\*]*
 NUMBER          (\-|\+)?[0-9]{1,20}
 RANGE           \({NUMBER}[ ]?\-[ ]?{NUMBER}\)
+ASNUM           ASNUM
 
 /* yytext shall be a pointer */
 %pointer
@@ -73,6 +74,7 @@ RANGE           \({NUMBER}[ ]?\-[ ]?{NUMBER}\)
 %}
 
 [ \t]+          LOC_STEP /* ignore whitespace */;
+{ASNUM}         {yylval->string = XSTRDUP(MTYPE_LEX, yytext); return ASNUM;}
 {IPV4}          {yylval->string = XSTRDUP(MTYPE_LEX, yytext); return IPV4;}
 {IPV4_PREFIX}   {yylval->string = XSTRDUP(MTYPE_LEX, yytext); return IPV4_PREFIX;}
 {IPV6}          {yylval->string = XSTRDUP(MTYPE_LEX, yytext); return IPV6;}