]>
git.ipfire.org Git - people/ms/network.git/blob - src/inetcalc.c
1 /*#############################################################################
3 # IPFire.org - A linux based firewall #
4 # Copyright (C) 2015 IPFire Network Development Team #
6 # This program is free software: you can redistribute it and/or modify #
7 # it under the terms of the GNU General Public License as published by #
8 # the Free Software Foundation, either version 3 of the License, or #
9 # (at your option) any later version. #
11 # This program is distributed in the hope that it will be useful, #
12 # but WITHOUT ANY WARRANTY; without even the implied warranty of #
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
14 # GNU General Public License for more details. #
16 # You should have received a copy of the GNU General Public License #
17 # along with this program. If not, see <http://www.gnu.org/licenses/>. #
19 #############################################################################*/
22 #include <arpa/inet.h>
25 #include <netinet/in.h>
29 #include <sys/socket.h>
31 typedef struct ip_address
{
37 static struct in6_addr
prefix_to_bitmask(int prefix
) {
38 assert(prefix
<= 128);
40 struct in6_addr bitmask
;
42 for (int i
= 0; i
< 16; i
++)
43 bitmask
.s6_addr
[i
] = 0;
45 for (int i
= prefix
, j
= 0; i
> 0; i
-= 8, j
++) {
47 bitmask
.s6_addr
[j
] = 0xff;
49 bitmask
.s6_addr
[j
] = 0xff << (8 - i
);
55 static int bitmask_to_prefix(uint32_t bits
) {
58 // Count all ones until we find the first zero
59 while (bits
& (1 << 31)) {
64 // The remaining bits must all be zero
71 static int ip_address_parse_subnet_mask(ip_address_t
* ip
, const char* prefix
) {
74 int r
= inet_pton(AF_INET
, prefix
, &mask
.s_addr
);
78 uint32_t bits
= ntohl(mask
.s_addr
);
79 ip
->prefix
= bitmask_to_prefix(bits
);
81 return (ip
->prefix
< 0 || ip
->prefix
> 32);
84 static int ip_address_parse_prefix_cidr(ip_address_t
* ip
, const int family
, const char* prefix
) {
89 if (p
>= '0' && p
<= '9') {
91 ip
->prefix
+= p
- '0';
99 return (ip
->prefix
< 0 || ip
->prefix
> 128);
102 return (ip
->prefix
< 0 || ip
->prefix
> 32);
109 static int ip_address_parse_prefix(ip_address_t
* ip
, const int family
, const char* prefix
) {
110 int r
= ip_address_parse_prefix_cidr(ip
, family
, prefix
);
112 if (r
&& family
== AF_INET
) {
113 r
= ip_address_parse_subnet_mask(ip
, prefix
);
119 static int default_prefix(const int family
) {
132 static int ip_address_parse_simple(ip_address_t
* ip
, const int family
, const char* address
) {
133 assert(family
== AF_INET
|| family
== AF_INET6
);
135 size_t address_length
= strlen(address
);
136 char buffer
[address_length
+ 1];
137 strncpy(buffer
, address
, sizeof(buffer
));
139 // Search for a prefix or subnet mask
140 char* prefix
= strchr(buffer
, '/');
142 buffer
[prefix
- buffer
] = '\0';
146 memset(&ip
->addr
, 0, sizeof(ip
->addr
));
147 int r
= inet_pton(family
, buffer
, &ip
->addr
);
150 // If parsing the IP address failed, we will return false
154 // If the IP address could be successfully parsed, we will
155 // save the address family and return true
166 r
= ip_address_parse_prefix(ip
, family
, prefix
);
168 ip
->prefix
= default_prefix(family
);
173 static int ip_address_parse(ip_address_t
* ip
, const int family
, const char* address
) {
174 static int families
[] = { AF_INET
, AF_INET6
, 0 };
179 if (family
== AF_UNSPEC
|| family
== *f
) {
180 r
= ip_address_parse_simple(ip
, *f
, address
);
192 static int ip_address_eq(const ip_address_t
* a1
, const ip_address_t
* a2
) {
193 if (a1
->family
!= a2
->family
)
196 if (!IN6_ARE_ADDR_EQUAL(&a1
->addr
, &a2
->addr
))
199 if (a1
->prefix
!= a2
->prefix
)
205 static int ip_address_gt(const ip_address_t
* a1
, const ip_address_t
* a2
) {
206 if (a1
->family
!= a2
->family
|| a1
->prefix
!= a2
->prefix
)
209 if (memcmp(&a1
->addr
.s6_addr
, &a2
->addr
.s6_addr
, sizeof(a1
->addr
.s6_addr
)) > 0)
215 static int ip_address_ge(const ip_address_t
* a1
, const ip_address_t
* a2
) {
216 int r
= ip_address_eq(a1
, a2
);
220 return ip_address_gt(a1
, a2
);
223 static int ip_address_le(const ip_address_t
* a1
, const ip_address_t
* a2
) {
224 int r
= ip_address_eq(a1
, a2
);
228 return !ip_address_gt(a1
, a2
);
231 static int ip_address_format_string(char* buffer
, size_t size
, const ip_address_t
* ip
) {
232 assert(ip
->family
== AF_INET
|| ip
->family
== AF_INET6
);
234 const char* p
= inet_ntop(ip
->family
, &ip
->addr
.s6_addr
, buffer
, size
);
241 static void ip_address_print(const ip_address_t
* ip
) {
242 char buffer
[INET6_ADDRSTRLEN
+4];
244 int r
= ip_address_format_string(buffer
, sizeof(buffer
), ip
);
248 if (ip
->prefix
>= 0) {
249 size_t len
= strlen(buffer
);
250 snprintf(buffer
+ len
, sizeof(buffer
) - len
, "/%d", ip
->prefix
);
253 printf("%s\n", buffer
);
256 static void ip_address_get_first_address(ip_address_t
* first
, const ip_address_t
* network
) {
257 assert(network
->prefix
>= 0);
259 struct in6_addr mask
= prefix_to_bitmask(network
->prefix
);
261 first
->family
= network
->family
;
262 first
->prefix
= default_prefix(network
->family
);
264 for (int i
= 0; i
< 16; i
++)
265 first
->addr
.s6_addr
[i
] = network
->addr
.s6_addr
[i
] & mask
.s6_addr
[i
];
268 static void ip_address_get_last_address(ip_address_t
* last
, const ip_address_t
* network
) {
269 assert(network
->prefix
>= 0);
271 struct in6_addr mask
= prefix_to_bitmask(network
->prefix
);
273 last
->family
= network
->family
;
274 last
->prefix
= default_prefix(network
->family
);
276 for (int i
= 0; i
< 16; i
++)
277 last
->addr
.s6_addr
[i
] = network
->addr
.s6_addr
[i
] | ~mask
.s6_addr
[i
];
280 static void ip_address_make_network(ip_address_t
* net
, const ip_address_t
* network
) {
281 ip_address_get_first_address(net
, network
);
284 net
->prefix
= network
->prefix
;
287 static void ip_address_make_broadcast(ip_address_t
* broadcast
, const ip_address_t
* network
) {
288 assert(network
->family
== AF_INET
);
290 ip_address_get_last_address(broadcast
, network
);
293 broadcast
->prefix
= network
->prefix
;
296 static int ip_address_is_subset(const ip_address_t
* network1
, const ip_address_t
* network2
) {
302 // Get the first address of the networks
303 ip_address_get_first_address(&first1
, network1
);
304 ip_address_get_first_address(&first2
, network2
);
306 // Get the highest address in both networks
307 ip_address_get_last_address(&last1
, network1
);
308 ip_address_get_last_address(&last2
, network2
);
310 // The start address must be in the network
311 if (ip_address_ge(&first1
, &first2
) == 0 && ip_address_le(&first1
, &last2
) == 0) {
312 // The end address must be in the network, too
313 if (ip_address_ge(&last1
, &first2
) == 0 && ip_address_le(&last1
, &last2
) == 0) {
321 static int action_check(const int family
, const char* address
) {
324 int r
= ip_address_parse(&ip
, family
, address
);
328 // If the prefix is the host prefix this is a host address
329 if (ip
.prefix
== default_prefix(family
))
335 static int action_equal(const int family
, const char* addr1
, const char* addr2
) {
340 r
= ip_address_parse(&a1
, family
, addr1
);
344 r
= ip_address_parse(&a2
, family
, addr2
);
348 return ip_address_eq(&a1
, &a2
);
351 static int action_greater(const int family
, const char* addr1
, const char* addr2
) {
356 r
= ip_address_parse(&a1
, family
, addr1
);
360 r
= ip_address_parse(&a2
, family
, addr2
);
364 return ip_address_gt(&a1
, &a2
);
367 static int action_format(const int family
, const char* address
) {
370 int r
= ip_address_parse(&ip
, family
, address
);
374 ip_address_print(&ip
);
378 static int action_broadcast(const int family
, const char* address
) {
380 int r
= ip_address_parse(&ip
, family
, address
);
382 fprintf(stderr
, "Invalid IP address: %s\n", address
);
386 if (ip
.family
!= AF_INET
) {
387 fprintf(stderr
, "This is only possible for IPv4\n");
391 ip_address_t broadcast
;
392 ip_address_make_broadcast(&broadcast
, &ip
);
394 ip_address_print(&broadcast
);
398 static int action_network(const int family
, const char* address
) {
401 int r
= ip_address_parse(&ip
, family
, address
);
403 fprintf(stderr
, "Invalid IP address: %s\n", address
);
407 ip_address_t network
;
408 ip_address_make_network(&network
, &ip
);
410 ip_address_print(&network
);
414 static int action_prefix(const int family
, const char* addr1
, const char* addr2
) {
417 ip_address_t network
;
418 r
= ip_address_parse(&network
, family
, addr1
);
422 ip_address_t broadcast
;
423 r
= ip_address_parse(&broadcast
, family
, addr2
);
427 r
= ip_address_gt(&broadcast
, &network
);
431 struct in6_addr netmask
;
432 for (int i
= 0; i
< 16; i
++)
433 netmask
.s6_addr
[i
] = network
.addr
.s6_addr
[i
] ^ broadcast
.addr
.s6_addr
[i
];
435 uint32_t mask
= netmask
.s6_addr
[0] << 24 | netmask
.s6_addr
[1] << 16 |
436 netmask
.s6_addr
[2] << 8 | netmask
.s6_addr
[3];
438 int prefix
= bitmask_to_prefix(~mask
);
442 printf("%d\n", prefix
);
446 static int action_subset(const int family
, const char* address1
, const char* address2
) {
448 ip_address_t network1
;
449 ip_address_t network2
;
451 // Parse both networks and/or IP addresses
452 r
= ip_address_parse(&network1
, family
, address1
);
456 r
= ip_address_parse(&network2
, family
, address2
);
460 if (network1
.family
!= network2
.family
) {
461 fprintf(stderr
, "Address family of both arguments must match\n");
465 return ip_address_is_subset(&network1
, &network2
);
480 static void set_action(int* action
, int what
) {
481 if (*action
!= AC_UNSPEC
) {
482 printf("Another action has already been selected\n");
489 static struct option long_options
[] = {
490 {"broadcast", no_argument
, 0, 'b'},
491 {"check", no_argument
, 0, 'c'},
492 {"equal", no_argument
, 0, 'e'},
493 {"format", no_argument
, 0, 'f'},
494 {"greater", no_argument
, 0, 'g'},
495 {"ipv4-only", no_argument
, 0, '4'},
496 {"ipv6-only", no_argument
, 0, '6'},
497 {"network", no_argument
, 0, 'n'},
498 {"prefix", no_argument
, 0, 'p'},
499 {"subset", no_argument
, 0, 's'},
500 {"verbose", no_argument
, 0, 'v'},
504 int main(int argc
, char** argv
) {
505 int option_index
= 0;
506 int required_arguments
= 0;
509 int action
= AC_UNSPEC
;
510 int family
= AF_UNSPEC
;
513 int c
= getopt_long(argc
, argv
, "46bcefgnpsv", long_options
, &option_index
);
519 if (long_options
[option_index
].flag
!= 0)
522 printf("option: %s", long_options
[option_index
].name
);
524 printf(" with arg %s", optarg
);
537 set_action(&action
, AC_BROADCAST
);
538 required_arguments
= 1;
542 set_action(&action
, AC_CHECK
);
543 required_arguments
= 1;
547 set_action(&action
, AC_EQUAL
);
548 required_arguments
= 2;
552 set_action(&action
, AC_FORMAT
);
553 required_arguments
= 1;
557 set_action(&action
, AC_GREATER
);
558 required_arguments
= 2;
562 set_action(&action
, AC_NETWORK
);
563 required_arguments
= 1;
567 set_action(&action
, AC_PREFIX
);
568 required_arguments
= 2;
572 set_action(&action
, AC_SUBSET
);
573 required_arguments
= 2;
593 if (argc
!= required_arguments
) {
594 fprintf(stderr
, "Invalid number of arguments. Got %d, required %d.\n",
595 argc
, required_arguments
);
599 if (verbose
&& family
!= AF_UNSPEC
)
600 printf("Address family = %d\n", family
);
606 printf("No action specified\n");
611 r
= action_broadcast(family
, argv
[0]);
615 r
= action_check(family
, argv
[0]);
619 printf("%s is a valid IP address\n", argv
[0]);
621 printf("%s is not a valid IP address\n", argv
[0]);
626 r
= action_equal(family
, argv
[0], argv
[1]);
630 printf("%s equals %s\n", argv
[0], argv
[1]);
632 printf("Invalid IP address provided\n");
634 printf("%s does not equal %s\n", argv
[0], argv
[1]);
639 r
= action_format(family
, argv
[0]);
642 printf("Invalid IP address given\n");
647 r
= action_greater(family
, argv
[0], argv
[1]);
651 printf("%s is greater than %s\n", argv
[0], argv
[1]);
653 printf("Invalid IP address provided\n");
655 printf("%s is not greater than %s\n", argv
[0], argv
[1]);
660 r
= action_network(family
, argv
[0]);
664 r
= action_subset(family
, argv
[0], argv
[1]);
668 printf("%s is a subset of %s\n", argv
[0], argv
[1]);
670 printf("%s is not a subset of %s\n", argv
[0], argv
[1]);
676 r
= action_prefix(family
, argv
[0], argv
[1]);