1 /* The 'ipset' data structure and related algorithms in this file were
2 inspired by the 'ipaddr.py' library from Cendio Systems AB. */
8 #define DEFAULT_ALLOC 2
9 #define EXTEND_ALLOC_BY 4
11 struct subnet_list
*subnet_list_new(void)
13 struct subnet_list
*r
;
14 r
=safe_malloc(sizeof(*r
),"subnet_list_new:list");
16 r
->alloc
=DEFAULT_ALLOC
;
17 r
->list
=safe_malloc(sizeof(*r
->list
)*r
->alloc
,"subnet_list_new:data");
21 void subnet_list_free(struct subnet_list
*a
)
23 if (a
->list
) free(a
->list
);
27 static void subnet_list_set_len(struct subnet_list
*a
, uint32_t l
)
33 na
=a
->alloc
+EXTEND_ALLOC_BY
;
34 nd
=realloc(a
->list
,sizeof(*nd
)*na
);
36 fatal_perror("subnet_list_set_len: realloc");
44 void subnet_list_append(struct subnet_list
*a
, uint32_t prefix
, uint32_t len
)
47 subnet_list_set_len(a
,a
->entries
+1);
48 sn
=&a
->list
[a
->entries
-1];
51 sn
->mask
=len?
(0xffffffff << (32-len
)):0;
54 struct ipset
*ipset_new(void)
57 r
=safe_malloc(sizeof(*r
),"ipset_new:set");
60 r
->d
=safe_malloc(sizeof(*r
->d
)*r
->a
,"ipset_new:data");
64 void ipset_free(struct ipset
*a
)
71 static void ipset_dump(struct ipset
*a
, string_t name
)
76 for (i
=0; i
<a
->l
; i
++) {
77 printf("[%08x-%08x] ",a
->d
[i
].a
,a
->d
[i
].b
);
83 struct ipset
*ipset_from_subnet(struct subnet s
)
90 r
->d
[0].b
=s
.prefix
| (~s
.mask
);
94 struct ipset
*ipset_from_subnet_list(struct subnet_list
*l
)
96 struct ipset
*r
, *a
, *b
;
100 for (i
=0; i
<l
->entries
; i
++) {
101 a
=ipset_from_subnet(l
->list
[i
]);
110 static void ipset_set_len(struct ipset
*a
, uint32_t l
)
116 na
=a
->a
+EXTEND_ALLOC_BY
;
117 nd
=realloc(a
->d
,sizeof(*nd
)*na
);
119 fatal_perror("ipset_set_len: realloc");
127 static void ipset_append_range(struct ipset
*a
, struct iprange r
)
129 ipset_set_len(a
,a
->l
+1);
133 #define max(a,b) (a>b?a:b)
134 struct ipset
*ipset_union(struct ipset
*a
, struct ipset
*b
)
142 while (ia
<a
->l
|| ib
<b
->l
) {
145 if (a
->d
[ia
].a
< b
->d
[ib
].a
)
155 ipset_append_range(c
,r
);
156 else if (r
.a
<= c
->d
[c
->l
-1].b
+1)
157 /* Extends (or is consumed by) the last range */
158 c
->d
[c
->l
-1].b
=max(c
->d
[c
->l
-1].b
, r
.b
);
160 ipset_append_range(c
,r
);
165 struct ipset
*ipset_intersection(struct ipset
*a
, struct ipset
*b
)
168 struct iprange ra
, rb
;
174 while (ia
<a
->l
&& ib
<b
->l
) {
178 /* The first entry of a doesn't overlap with any part of b */
180 else if (ra
.a
> rb
.b
)
181 /* The first entry of b doesn't overlap with any part of a */
184 /* Trim away any leading edges */
186 /* a starts before b */
188 else if (ra
.a
> rb
.a
)
189 /* b starts before a */
192 /* Now the ranges start at the same point */
194 /* The ranges are equal */
195 ipset_append_range(r
,ra
);
198 } else if (ra
.b
< rb
.b
) {
199 /* a is the smaller range */
200 ipset_append_range(r
,ra
);
203 /* y is the smaller range */
204 ipset_append_range(r
,rb
);
212 struct ipset
*ipset_complement(struct ipset
*a
)
221 for (i
=0; i
<a
->l
; i
++) {
227 ipset_append_range(r
,n
);
231 if (pre
!=0xffffffff) {
234 ipset_append_range(r
,n
);
240 struct ipset
*ipset_subtract(struct ipset
*a
, struct ipset
*b
)
243 c
=ipset_complement(b
);
244 r
=ipset_intersection(a
,c
);
249 bool_t
ipset_is_empty(struct ipset
*a
)
254 bool_t
ipset_contains_addr(struct ipset
*a
, uint32_t addr
)
259 for (i
=0; i
<a
->l
; i
++) {
261 if (addr
>=r
.a
&& addr
<=r
.b
) return True
;
262 if (addr
<r
.a
) return False
;
267 /* sub is a subset of super if it does not intersect with the complement
269 bool_t
ipset_is_subset(struct ipset
*super
, struct ipset
*sub
)
271 struct ipset
*superc
;
275 superc
=ipset_complement(super
);
276 inter
=ipset_intersection(superc
,sub
);
277 empty
=ipset_is_empty(inter
);
283 struct subnet_list
*ipset_to_subnet_list(struct ipset
*is
)
285 struct subnet_list
*r
;
288 uint32_t lomask
,lobit
,himask
,bits
;
291 for (i
=0; i
<is
->l
; i
++) {
300 if ((a
& lomask
) != 0) {
301 subnet_list_append(r
,a
,bits
);
303 } else if ((b
& lomask
) != lomask
) {
304 subnet_list_append(r
,b
&himask
,bits
);
307 lomask
= (lomask
<< 1) | 1;
308 lobit
= (lobit
<< 1);
309 himask
= himask
^ lobit
;
319 /* The string buffer must be at least 16 bytes long */
320 string_t
ipaddr_to_string(uint32_t addr
)
325 s
=safe_malloc(16,"ipaddr_to_string");
330 snprintf(s
, 16, "%d.%d.%d.%d", a
, b
, c
, d
);
334 string_t
subnet_to_string(struct subnet sn
)
336 uint32_t addr
=sn
.prefix
;
340 s
=safe_malloc(19,"subnet_to_string");
345 snprintf(s
, 19, "%d.%d.%d.%d/%d", a
, b
, c
, d
, sn
.len
);
349 static struct subnet
string_item_to_subnet(item_t
*i
, string_t desc
,
353 uint32_t a
, b
, c
, d
, n
;
359 /* i is not guaranteed to be a string */
360 if (i
->type
!=t_string
) {
361 cfgfatal(i
->loc
,desc
,"expecting a string (subnet specification)\n");
365 if (strcmp(in
,"default")==0) {
376 /* We expect strings of the form "a.b.c.d[/n]", i.e. the dots are
377 NOT optional. The subnet mask is optional; if missing it is assumed
379 match
=sscanf(in
,"%u.%u.%u.%u/%u", &a
, &b
, &c
, &d
, &n
);
381 cfgfatal(i
->loc
,desc
,"\"%s\" is not a valid "
382 "subnet specification\n",in
);
387 if (a
>255 || b
>255 || c
>255 || d
>255 || n
>32) {
388 cfgfatal(i
->loc
,desc
,"\"%s\": range error\n",in
);
390 s
.prefix
=(a
<<24)|(b
<<16)|(c
<<8)|(d
);
391 s
.mask
=n?
(~0UL << (32-n
)):0;
393 if (s
.prefix
& ~s
.mask
) {
394 cfgfatal(i
->loc
,desc
,"\"%s\": prefix not fully contained "
400 uint32_t string_item_to_ipaddr(item_t
*i
, string_t desc
)
405 /* i is not guaranteed to be a string */
406 if (i
->type
!=t_string
) {
407 cfgfatal(i
->loc
,desc
,"expecting a string (IP address)\n");
410 match
=sscanf(i
->data
.string
,"%u.%u.%u.%u", &a
, &b
, &c
, &d
);
412 cfgfatal(i
->loc
,desc
,"\"%s\" is not a valid "
413 "IP address\n",i
->data
.string
);
415 if (a
>255 || b
>255 || c
>255 || d
>255) {
416 cfgfatal(i
->loc
,desc
,"\"%s\": range error\n",i
->data
.string
);
418 return (a
<<24)|(b
<<16)|(c
<<8)|(d
);
421 struct ipset
*string_list_to_ipset(list_t
*l
, struct cloc loc
,
422 string_t module
, string_t param
)
424 struct ipset
*r
, *n
, *isn
;
431 for (i
=0; i
<e
; i
++) {
433 isn
=ipset_from_subnet(string_item_to_subnet(item
,param
,&inv
));
435 n
=ipset_subtract(r
,isn
);
437 n
=ipset_union(r
,isn
);