diff options
| -rw-r--r-- | filter/trie.c | 22 | ||||
| -rw-r--r-- | lib/ip.h | 18 | ||||
| -rw-r--r-- | lib/ip_test.c | 66 |
3 files changed, 90 insertions, 16 deletions
diff --git a/filter/trie.c b/filter/trie.c index dbed5ace..5d9cc952 100644 --- a/filter/trie.c +++ b/filter/trie.c @@ -424,9 +424,6 @@ trie_add_prefix(struct f_trie *t, const net_addr *net, uint l, uint h) static int trie_match_net4(const struct f_trie *t, ip4_addr px, uint plen) { - ip4_addr pmask = ip4_mkmask(plen); - ip4_addr paddr = ip4_and(px, pmask); - if (plen == 0) return t->zero; @@ -437,10 +434,8 @@ trie_match_net4(const struct f_trie *t, ip4_addr px, uint plen) while (n) { - ip4_addr cmask = ip4_and(n->mask, pmask); - /* We are out of path */ - if (ip4_compare(ip4_and(paddr, cmask), ip4_and(n->addr, cmask))) + if (!ip4_prefix_equal(px, n->addr, MIN(plen, n->plen))) return 0; /* Check local mask */ @@ -452,11 +447,11 @@ trie_match_net4(const struct f_trie *t, ip4_addr px, uint plen) return 1; /* We finished trie walk and still no match */ - if (plen <= n->plen) + if (nlen <= n->plen) return 0; /* Choose children */ - n = n->c[ip4_getbits(paddr, n->plen, TRIE_STEP)]; + n = n->c[ip4_getbits(px, n->plen, TRIE_STEP)]; } return 0; @@ -465,9 +460,6 @@ trie_match_net4(const struct f_trie *t, ip4_addr px, uint plen) static int trie_match_net6(const struct f_trie *t, ip6_addr px, uint plen) { - ip6_addr pmask = ip6_mkmask(plen); - ip6_addr paddr = ip6_and(px, pmask); - if (plen == 0) return t->zero; @@ -478,10 +470,8 @@ trie_match_net6(const struct f_trie *t, ip6_addr px, uint plen) while (n) { - ip6_addr cmask = ip6_and(n->mask, pmask); - /* We are out of path */ - if (ip6_compare(ip6_and(paddr, cmask), ip6_and(n->addr, cmask))) + if (!ip6_prefix_equal(px, n->addr, MIN(plen, n->plen))) return 0; /* Check local mask */ @@ -493,11 +483,11 @@ trie_match_net6(const struct f_trie *t, ip6_addr px, uint plen) return 1; /* We finished trie walk and still no match */ - if (plen <= n->plen) + if (nlen <= n->plen) return 0; /* Choose children */ - n = n->c[ip6_getbits(paddr, n->plen, TRIE_STEP)]; + n = n->c[ip6_getbits(px, n->plen, TRIE_STEP)]; } return 0; @@ -279,6 +279,24 @@ static inline uint ip6_pxlen(ip6_addr a, ip6_addr b) return 32 * i + 31 - u32_log2(a.addr[i] ^ b.addr[i]); } +static inline int ip4_prefix_equal(ip4_addr a, ip4_addr b, uint n) +{ + return (_I(a) ^ _I(b)) < ((u64) 1 << (32 - n)); +} + +static inline int ip6_prefix_equal(ip6_addr a, ip6_addr b, uint n) +{ + uint n0 = n / 32; + uint n1 = n % 32; + + return + ((n0 <= 0) || (_I0(a) == _I0(b))) && + ((n0 <= 1) || (_I1(a) == _I1(b))) && + ((n0 <= 2) || (_I2(a) == _I2(b))) && + ((n0 <= 3) || (_I3(a) == _I3(b))) && + (!n1 || ((a.addr[n0] ^ b.addr[n0]) < (1u << (32 - n1)))); +} + static inline u32 ip4_getbit(ip4_addr a, uint pos) { return (_I(a) >> (31 - pos)) & 1; } diff --git a/lib/ip_test.c b/lib/ip_test.c index 36d10d68..eee0a427 100644 --- a/lib/ip_test.c +++ b/lib/ip_test.c @@ -167,6 +167,70 @@ t_ip6_ntop(void) return bt_assert_batch(test_vectors, test_ipa_ntop, bt_fmt_ipa, bt_fmt_str); } +static int +t_ip4_prefix_equal(void) +{ + bt_assert( ip4_prefix_equal(ip4_from_u32(0x12345678), ip4_from_u32(0x1234ffff), 16)); + bt_assert(!ip4_prefix_equal(ip4_from_u32(0x12345678), ip4_from_u32(0x1234ffff), 17)); + bt_assert( ip4_prefix_equal(ip4_from_u32(0x12345678), ip4_from_u32(0x12345000), 21)); + bt_assert(!ip4_prefix_equal(ip4_from_u32(0x12345678), ip4_from_u32(0x12345000), 22)); + + bt_assert( ip4_prefix_equal(ip4_from_u32(0x00000000), ip4_from_u32(0xffffffff), 0)); + bt_assert( ip4_prefix_equal(ip4_from_u32(0x12345678), ip4_from_u32(0x12345678), 0)); + + bt_assert( ip4_prefix_equal(ip4_from_u32(0x12345678), ip4_from_u32(0x12345678), 32)); + bt_assert(!ip4_prefix_equal(ip4_from_u32(0x12345678), ip4_from_u32(0x12345679), 32)); + bt_assert(!ip4_prefix_equal(ip4_from_u32(0x12345678), ip4_from_u32(0x92345678), 32)); + + return 1; +} + +static int +t_ip6_prefix_equal(void) +{ + bt_assert( ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + ip6_build(0x20010db8, 0x1234ffff, 0xfefefefe, 0xdcdcdcdc), + 48)); + + bt_assert(!ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + ip6_build(0x20010db8, 0x1234ffff, 0xfefefefe, 0xdcdcdcdc), + 49)); + + bt_assert(!ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + ip6_build(0x20020db8, 0x12345678, 0xfefefefe, 0xdcdcdcdc), + 48)); + + bt_assert( ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + ip6_build(0x20010db8, 0x12345678, 0xfefefefe, 0xdcdcdcdc), + 64)); + + bt_assert(!ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + ip6_build(0x20010db8, 0x1234567e, 0xfefefefe, 0xdcdcdcdc), + 64)); + + bt_assert( ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20002020), + ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + 106)); + + bt_assert(!ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20002020), + ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + 107)); + + bt_assert( ip6_prefix_equal(ip6_build(0xfeef0db8, 0x87654321, 0x10101010, 0x20202020), + ip6_build(0x20010db8, 0x12345678, 0xfefefefe, 0xdcdcdcdc), + 0)); + + bt_assert( ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + 128)); + + bt_assert(!ip6_prefix_equal(ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202020), + ip6_build(0x20010db8, 0x12345678, 0x10101010, 0x20202021), + 128)); + + return 1; +} + int main(int argc, char *argv[]) { @@ -176,6 +240,8 @@ main(int argc, char *argv[]) bt_test_suite(t_ip6_pton, "Converting IPv6 string to ip6_addr struct"); bt_test_suite(t_ip4_ntop, "Converting ip4_addr struct to IPv4 string"); bt_test_suite(t_ip6_ntop, "Converting ip6_addr struct to IPv6 string"); + bt_test_suite(t_ip4_prefix_equal, "Testing ip4_prefix_equal()"); + bt_test_suite(t_ip6_prefix_equal, "Testing ip6_prefix_equal()"); return bt_exit_value(); } |