From 3ac8e5433f20bfb5e12b918252643106a2de52af Mon Sep 17 00:00:00 2001 From: Tom Gundersen Date: Tue, 22 Sep 2015 17:54:27 +0200 Subject: networkd: address - add hash helpers for Address objects Add compare_func and hash_func for the Address object. The notion of address equality is the same as in the kernel, and hashing preserves preserves equality. Two addresses are considered equal if: - they have the same address family, and - they are neither IPv4 nor IPv6 addresses, or - the local addresses are identical, and - they are IPv6 addresses, or - they have the same prefixlength, and - their peer prefixes are identical This fixes a bug in the old equality check, which got the local address and the peer prefix mixed up. --- src/network/networkd-address.c | 149 +++++++++++++++++++++++++++-------------- src/network/test-network.c | 9 +-- 2 files changed, 105 insertions(+), 53 deletions(-) diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c index b2f24ec305..efbdda5939 100644 --- a/src/network/networkd-address.c +++ b/src/network/networkd-address.c @@ -21,11 +21,12 @@ #include -#include "utf8.h" -#include "util.h" #include "conf-parser.h" #include "firewall-util.h" #include "netlink-util.h" +#include "set.h" +#include "utf8.h" +#include "util.h" #include "networkd.h" #include "networkd-address.h" @@ -97,6 +98,103 @@ void address_free(Address *address) { free(address); } +static void address_hash_func(const void *b, struct siphash *state) { + const Address *a = b; + + assert(a); + + siphash24_compress(&a->family, sizeof(a->family), state); + + switch (a->family) { + case AF_INET: + siphash24_compress(&a->prefixlen, sizeof(a->prefixlen), state); + + /* peer prefix */ + if (a->prefixlen != 0) { + uint32_t prefix; + + if (a->in_addr_peer.in.s_addr != 0) + prefix = be32toh(a->in_addr_peer.in.s_addr) >> (32 - a->prefixlen); + else + prefix = be32toh(a->in_addr.in.s_addr) >> (32 - a->prefixlen); + + siphash24_compress(&prefix, sizeof(prefix), state); + } + + /* fallthrough */ + case AF_INET6: + /* local address */ + siphash24_compress(&a->in_addr, FAMILY_ADDRESS_SIZE(a->family), state); + + break; + default: + /* treat any other address family as AF_UNSPEC */ + break; + } +} + +static int address_compare_func(const void *c1, const void *c2) { + const Address *a1 = c1, *a2 = c2; + + if (a1->family < a2->family) + return -1; + if (a1->family > a2->family) + return 1; + + switch (a1->family) { + /* use the same notion of equality as the kernel does */ + case AF_INET: + if (a1->prefixlen < a2->prefixlen) + return -1; + if (a1->prefixlen > a2->prefixlen) + return 1; + + /* compare the peer prefixes */ + if (a1->prefixlen != 0) { + /* make sure we don't try to shift by 32. + * See ISO/IEC 9899:TC3 § 6.5.7.3. */ + uint32_t b1, b2; + + if (a1->in_addr_peer.in.s_addr != 0) + b1 = be32toh(a1->in_addr_peer.in.s_addr) >> (32 - a1->prefixlen); + else + b1 = be32toh(a1->in_addr.in.s_addr) >> (32 - a1->prefixlen); + + if (a2->in_addr_peer.in.s_addr != 0) + b2 = be32toh(a2->in_addr_peer.in.s_addr) >> (32 - a1->prefixlen); + else + b2 = be32toh(a2->in_addr.in.s_addr) >> (32 - a1->prefixlen); + + if (b1 < b2) + return -1; + if (b1 > b2) + return 1; + } + + /* fall-through */ + case AF_INET6: + return memcmp(&a1->in_addr, &a2->in_addr, FAMILY_ADDRESS_SIZE(a1->family)); + default: + /* treat any other address family as AF_UNSPEC */ + return 0; + } +} + +static const struct hash_ops address_hash_ops = { + .hash = address_hash_func, + .compare = address_compare_func +}; + +bool address_equal(Address *a1, Address *a2) { + if (a1 == a2) + return true; + + if (!a1 || !a2) + return false; + + return address_compare_func(a1, a2) == 0; +} + int address_establish(Address *address, Link *link) { bool masq; int r; @@ -572,50 +670,3 @@ int config_parse_label(const char *unit, return 0; } - -bool address_equal(Address *a1, Address *a2) { - /* same object */ - if (a1 == a2) - return true; - - /* one, but not both, is NULL */ - if (!a1 || !a2) - return false; - - if (a1->family != a2->family) - return false; - - switch (a1->family) { - /* use the same notion of equality as the kernel does */ - case AF_UNSPEC: - return true; - - case AF_INET: - if (a1->prefixlen != a2->prefixlen) - return false; - else if (a1->prefixlen == 0) - /* make sure we don't try to shift by 32. - * See ISO/IEC 9899:TC3 § 6.5.7.3. */ - return true; - else { - uint32_t b1, b2; - - b1 = be32toh(a1->in_addr.in.s_addr); - b2 = be32toh(a2->in_addr.in.s_addr); - - return (b1 >> (32 - a1->prefixlen)) == (b2 >> (32 - a1->prefixlen)); - } - - case AF_INET6: { - uint64_t *b1, *b2; - - b1 = (uint64_t*)&a1->in_addr.in6; - b2 = (uint64_t*)&a2->in_addr.in6; - - return (((b1[0] ^ b2[0]) | (b1[1] ^ b2[1])) == 0UL); - } - - default: - assert_not_reached("Invalid address family"); - } -} diff --git a/src/network/test-network.c b/src/network/test-network.c index 80676651a9..bac1d6781d 100644 --- a/src/network/test-network.c +++ b/src/network/test-network.c @@ -158,17 +158,18 @@ static void test_address_equality(void) { assert_se(address_equal(a1, a2)); assert_se(inet_pton(AF_INET, "192.168.3.9", &a1->in_addr.in)); - assert_se(address_equal(a1, a2)); + assert_se(!address_equal(a1, a2)); assert_se(inet_pton(AF_INET, "192.168.3.9", &a2->in_addr.in)); assert_se(address_equal(a1, a2)); + assert_se(inet_pton(AF_INET, "192.168.3.10", &a1->in_addr_peer.in)); + assert_se(address_equal(a1, a2)); + assert_se(inet_pton(AF_INET, "192.168.3.11", &a2->in_addr_peer.in)); + assert_se(address_equal(a1, a2)); a1->prefixlen = 10; assert_se(!address_equal(a1, a2)); a2->prefixlen = 10; assert_se(address_equal(a1, a2)); - assert_se(inet_pton(AF_INET, "192.168.3.10", &a2->in_addr.in)); - assert_se(address_equal(a1, a2)); - a1->family = AF_INET6; assert_se(!address_equal(a1, a2)); -- cgit v1.2.3-54-g00ecf