summaryrefslogtreecommitdiffstats
path: root/src/shared/in-addr-util.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/shared/in-addr-util.c')
-rw-r--r--src/shared/in-addr-util.c211
1 files changed, 211 insertions, 0 deletions
diff --git a/src/shared/in-addr-util.c b/src/shared/in-addr-util.c
new file mode 100644
index 0000000000..98d2446e5d
--- /dev/null
+++ b/src/shared/in-addr-util.c
@@ -0,0 +1,211 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <arpa/inet.h>
+
+#include "in-addr-util.h"
+
+int in_addr_null(unsigned family, union in_addr_union *u) {
+ assert(u);
+
+ if (family == AF_INET)
+ return u->in.s_addr == 0;
+
+ if (family == AF_INET6)
+ return
+ u->in6.s6_addr32[0] == 0 &&
+ u->in6.s6_addr32[1] == 0 &&
+ u->in6.s6_addr32[2] == 0 &&
+ u->in6.s6_addr32[3] == 0;
+
+ return -EAFNOSUPPORT;
+}
+
+
+int in_addr_equal(unsigned family, union in_addr_union *a, union in_addr_union *b) {
+ assert(a);
+ assert(b);
+
+ if (family == AF_INET)
+ return a->in.s_addr == b->in.s_addr;
+
+ if (family == AF_INET6)
+ return
+ a->in6.s6_addr32[0] == b->in6.s6_addr32[0] &&
+ a->in6.s6_addr32[1] == b->in6.s6_addr32[1] &&
+ a->in6.s6_addr32[2] == b->in6.s6_addr32[2] &&
+ a->in6.s6_addr32[3] == b->in6.s6_addr32[3];
+
+ return -EAFNOSUPPORT;
+}
+
+int in_addr_prefix_intersect(
+ unsigned family,
+ const union in_addr_union *a,
+ unsigned aprefixlen,
+ const union in_addr_union *b,
+ unsigned bprefixlen) {
+
+ unsigned m;
+
+ assert(a);
+ assert(b);
+
+ /* Checks whether there are any addresses that are in both
+ * networks */
+
+ m = MIN(aprefixlen, bprefixlen);
+
+ if (family == AF_INET) {
+ uint32_t x, nm;
+
+ x = be32toh(a->in.s_addr ^ b->in.s_addr);
+ nm = (m == 0) ? 0 : 0xFFFFFFFFUL << (32 - m);
+
+ return (x & nm) == 0;
+ }
+
+ if (family == AF_INET6) {
+ unsigned i;
+
+ if (m > 128)
+ m = 128;
+
+ for (i = 0; i < 16; i++) {
+ uint8_t x, nm;
+
+ x = a->in6.s6_addr[i] ^ b->in6.s6_addr[i];
+
+ if (m < 8)
+ nm = 0xFF << (8 - m);
+ else
+ nm = 0xFF;
+
+ if ((x & nm) != 0)
+ return 0;
+
+ if (m > 8)
+ m -= 8;
+ else
+ m = 0;
+ }
+
+ return 1;
+ }
+
+ return -EAFNOSUPPORT;
+}
+
+int in_addr_prefix_next(unsigned family, union in_addr_union *u, unsigned prefixlen) {
+ assert(u);
+
+ /* Increases the network part of an address by one. Returns
+ * positive it that succeeds, or 0 if this overflows. */
+
+ if (prefixlen <= 0)
+ return 0;
+
+ if (family == AF_INET) {
+ uint32_t c, n;
+
+ if (prefixlen > 32)
+ prefixlen = 32;
+
+ c = be32toh(u->in.s_addr);
+ n = c + (1UL << (32 - prefixlen));
+ if (n < c)
+ return 0;
+ n &= 0xFFFFFFFFUL << (32 - prefixlen);
+
+ u->in.s_addr = htobe32(n);
+ return 1;
+ }
+
+ if (family == AF_INET6) {
+ struct in6_addr add = {}, result;
+ uint8_t overflow = 0;
+ unsigned i;
+
+ if (prefixlen > 128)
+ prefixlen = 128;
+
+ /* First calculate what we have to add */
+ add.s6_addr[(prefixlen-1) / 8] = 1 << (7 - (prefixlen-1) % 8);
+
+ for (i = 16; i > 0; i--) {
+ unsigned j = i - 1;
+
+ result.s6_addr[j] = u->in6.s6_addr[j] + add.s6_addr[j] + overflow;
+ overflow = (result.s6_addr[j] < u->in6.s6_addr[j]);
+ }
+
+ if (overflow)
+ return 0;
+
+ u->in6 = result;
+ return 1;
+ }
+
+ return -EAFNOSUPPORT;
+}
+
+int in_addr_to_string(unsigned family, const union in_addr_union *u, char **ret) {
+ char *x;
+ size_t l;
+
+ assert(u);
+ assert(ret);
+
+ if (family == AF_INET)
+ l = INET_ADDRSTRLEN;
+ else if (family == AF_INET6)
+ l = INET6_ADDRSTRLEN;
+ else
+ return -EAFNOSUPPORT;
+
+ x = new(char, l);
+ if (!x)
+ return -ENOMEM;
+
+ errno = 0;
+ if (!inet_ntop(family, u, x, l)) {
+ free(x);
+ return errno ? -errno : -EINVAL;
+ }
+
+ *ret = x;
+ return 0;
+}
+
+int in_addr_from_string(unsigned family, const char *s, union in_addr_union *ret) {
+
+ assert(s);
+ assert(ret);
+
+ if (!IN_SET(family, AF_INET, AF_INET6))
+ return -EAFNOSUPPORT;
+
+ errno = 0;
+ if (inet_pton(family, s, ret) <= 0)
+ return errno ? -errno : -EINVAL;
+
+ return 0;
+}