1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
/*
* BIRD -- Configuration Parser Top
*
* (c) 1998--2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
/**
* DOC: Parser
*
* Both the configuration and CLI commands are analysed using a syntax
* driven parser generated by the |bison| tool from a grammar which
* is constructed from information gathered from grammar snippets by
* the |gen_parser.m4| script.
*
* Grammar snippets are files (usually with extension |.Y|) contributed
* by various BIRD modules to provide information about syntax of their
* configuration and their CLI commands. Each snipped consists of several
* section, each of them starting with a special keyword: |CF_HDR| for
* a list of |#include| directives needed by the C code, |CF_DEFINES|
* for a list of C declarations, |CF_DECLS| for |bison| declarations
* including keyword definitions specified as |CF_KEYWORDS|, |CF_GRAMMAR|
* for the grammar rules, |CF_CODE| for auxillary C code and finally
* |CF_END| at the end of the snippet.
*
* To create references between the snippets, it's possible to define
* multi-part rules by utilizing the |CF_ADDTO| macro which adds a new
* alternative to a multi-part rule.
*
* CLI commands are defined using a |CF_CLI| macro. Its parameters are:
* the list of keywords determining the command, the list of paramaters,
* help text for the parameters and help text for the command.
*
* Values of |enum| filter types can be defined using |CF_ENUM| with
* the following parameters: name of filter type, prefix common for all
* literals of this type, names of all the possible values.
*/
CF_HDR
#include "nest/bird.h"
#include "conf/conf.h"
#include "lib/resource.h"
#include "lib/socket.h"
#include "lib/timer.h"
#include "lib/string.h"
#include "nest/protocol.h"
#include "nest/iface.h"
#include "nest/route.h"
#include "nest/cli.h"
#include "filter/filter.h"
/* FIXME: Turn on YYERROR_VERBOSE and work around lots of bison bugs? */
CF_DECLS
%union {
int i;
u32 i32;
ip_addr a;
struct symbol *s;
char *t;
struct rtable_config *r;
struct f_inst *x;
struct filter *f;
struct f_tree *e;
struct f_val v;
struct f_path_mask *h;
struct password_item *p;
struct rt_show_data *ra;
void *g;
bird_clock_t time;
struct prefix px;
}
%token END CLI_MARKER INVALID_TOKEN
%token GEQ LEQ NEQ AND OR
%token <i> NUM ENUM
%token <i32> RTRID
%token <a> IPA
%token <s> SYM
%token <t> TEXT
%type <i> expr bool pxlen
%type <time> datetime
%type <a> ipa
%type <px> prefix prefix_or_ipa
%nonassoc PREFIX_DUMMY
%nonassoc '=' '<' '>' '~' '.' GEQ LEQ NEQ AND OR
%left '+' '-'
%left '*' '/' '%'
%left '!'
CF_KEYWORDS(DEFINE, ON, OFF, YES, NO)
CF_GRAMMAR
/* Basic config file structure */
config: conf_entries END { return 0; }
| CLI_MARKER cli_cmd { return 0; }
;
conf_entries:
/* EMPTY */
| conf_entries conf
;
CF_ADDTO(conf, ';')
/* Constant expressions */
expr:
NUM
| '(' term ')' { $$ = f_eval_int($2); }
| SYM { if ($1->class != SYM_NUMBER) cf_error("Number expected"); else $$ = $1->aux; }
;
CF_ADDTO(conf, definition)
definition:
DEFINE SYM '=' expr ';' {
cf_define_symbol($2, SYM_NUMBER, NULL);
$2->aux = $4;
}
| DEFINE SYM '=' IPA ';' {
cf_define_symbol($2, SYM_IPA, cfg_alloc(sizeof(ip_addr)));
*(ip_addr *)$2->def = $4;
}
;
/* Switches */
bool:
expr {$$ = !!$1; }
| ON { $$ = 1; }
| YES { $$ = 1; }
| OFF { $$ = 0; }
| NO { $$ = 0; }
| /* Silence means agreement */ { $$ = 1; }
;
/* Addresses, prefixes and netmasks */
ipa:
IPA
| SYM {
if ($1->class != SYM_IPA) cf_error("IP address expected");
$$ = *(ip_addr *)$1->def;
}
;
prefix:
ipa pxlen {
if (!ip_is_prefix($1, $2)) cf_error("Invalid prefix");
$$.addr = $1; $$.len = $2;
}
;
prefix_or_ipa:
prefix
| ipa { $$.addr = $1; $$.len = BITS_PER_IP_ADDRESS; }
;
pxlen:
'/' expr {
if ($2 < 0 || $2 > BITS_PER_IP_ADDRESS) cf_error("Invalid prefix length %d", $2);
$$ = $2;
}
| ':' ipa {
$$ = ipa_mklen($2);
if ($$ < 0) cf_error("Invalid netmask %I", $2);
}
;
datetime:
TEXT {
$$ = tm_parse_date($1);
if (!$$)
cf_error("Invalid date");
}
;
CF_CODE
CF_END
|
