+
+
+int odhcpd_bmemcmp(const void *av, const void *bv, size_t bits)
+{
+ const uint8_t *a = av, *b = bv;
+ size_t bytes = bits / 8;
+ bits %= 8;
+
+ int res = memcmp(a, b, bytes);
+ if (res == 0 && bits > 0)
+ res = (a[bytes] >> (8 - bits)) - (b[bytes] >> (8 - bits));
+
+ return res;
+}
+
+
+void odhcpd_bmemcpy(void *av, const void *bv, size_t bits)
+{
+ uint8_t *a = av;
+ const uint8_t *b = bv;
+
+ size_t bytes = bits / 8;
+ bits %= 8;
+ memcpy(a, b, bytes);
+
+ if (bits > 0) {
+ uint8_t mask = (1 << (8 - bits)) - 1;
+ a[bytes] = (a[bytes] & mask) | ((~mask) & b[bytes]);
+ }
+}
+
+
+int odhcpd_netmask2bitlen(bool inet6, void *mask)
+{
+ int bits;
+ struct in_addr *v4;
+ struct in6_addr *v6;
+
+ if (inet6)
+ for (bits = 0, v6 = mask;
+ bits < 128 && (v6->s6_addr[bits / 8] << (bits % 8)) & 128;
+ bits++);
+ else
+ for (bits = 0, v4 = mask;
+ bits < 32 && (ntohl(v4->s_addr) << bits) & 0x80000000;
+ bits++);
+
+ return bits;
+}
+
+bool odhcpd_bitlen2netmask(bool inet6, unsigned int bits, void *mask)
+{
+ uint8_t b;
+ struct in_addr *v4;
+ struct in6_addr *v6;
+
+ if (inet6)
+ {
+ if (bits > 128)
+ return false;
+
+ v6 = mask;
+
+ for (unsigned int i = 0; i < sizeof(v6->s6_addr); i++)
+ {
+ b = (bits > 8) ? 8 : bits;
+ v6->s6_addr[i] = (uint8_t)(0xFF << (8 - b));
+ bits -= b;
+ }
+ }
+ else
+ {
+ if (bits > 32)
+ return false;
+
+ v4 = mask;
+ v4->s_addr = bits ? htonl(~((1 << (32 - bits)) - 1)) : 0;
+ }
+
+ return true;
+}