diff options
Diffstat (limited to 'src/vnet/ip/ip_checksum.c')
| -rw-r--r-- | src/vnet/ip/ip_checksum.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/src/vnet/ip/ip_checksum.c b/src/vnet/ip/ip_checksum.c new file mode 100644 index 00000000000..6a9cf657a5c --- /dev/null +++ b/src/vnet/ip/ip_checksum.c @@ -0,0 +1,228 @@ +/* + * Copyright (c) 2015 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +/* + * ip4/ip_checksum.c: ip/tcp/udp checksums + * + * Copyright (c) 2008 Eliot Dresselhaus + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION + * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +#include <vnet/ip/ip.h> + +ip_csum_t +ip_incremental_checksum (ip_csum_t sum, void *_data, uword n_bytes) +{ + uword data = pointer_to_uword (_data); + ip_csum_t sum0, sum1; + + sum0 = 0; + sum1 = sum; + + /* Align data pointer to 64 bits. */ +#define _(t) \ +do { \ + if (n_bytes >= sizeof (t) \ + && sizeof (t) < sizeof (ip_csum_t) \ + && (data % (2 * sizeof (t))) != 0) \ + { \ + sum0 += * uword_to_pointer (data, t *); \ + data += sizeof (t); \ + n_bytes -= sizeof (t); \ + } \ +} while (0) + + _(u8); + _(u16); + if (BITS (ip_csum_t) > 32) + _(u32); + +#undef _ + + { + ip_csum_t *d = uword_to_pointer (data, ip_csum_t *); + + while (n_bytes >= 2 * sizeof (d[0])) + { + sum0 = ip_csum_with_carry (sum0, d[0]); + sum1 = ip_csum_with_carry (sum1, d[1]); + d += 2; + n_bytes -= 2 * sizeof (d[0]); + } + + data = pointer_to_uword (d); + } + +#define _(t) \ +do { \ + if (n_bytes >= sizeof (t) && sizeof (t) <= sizeof (ip_csum_t)) \ + { \ + sum0 = ip_csum_with_carry (sum0, * uword_to_pointer (data, t *)); \ + data += sizeof (t); \ + n_bytes -= sizeof (t); \ + } \ +} while (0) + + if (BITS (ip_csum_t) > 32) + _(u64); + _(u32); + _(u16); + _(u8); + +#undef _ + + /* Combine even and odd sums. */ + sum0 = ip_csum_with_carry (sum0, sum1); + + return sum0; +} + +ip_csum_t +ip_csum_and_memcpy (ip_csum_t sum, void *dst, void *src, uword n_bytes) +{ + uword n_left; + ip_csum_t sum0 = sum, sum1; + n_left = n_bytes; + + if (n_left && (pointer_to_uword (dst) & sizeof (u8))) + { + u8 *d8, val; + + d8 = dst; + val = ((u8 *) src)[0]; + d8[0] = val; + dst += 1; + src += 1; + n_left -= 1; + sum0 = + ip_csum_with_carry (sum0, val << (8 * CLIB_ARCH_IS_LITTLE_ENDIAN)); + } + + while ((n_left >= sizeof (u16)) + && (pointer_to_uword (dst) & (sizeof (sum) - sizeof (u16)))) + { + u16 *d16, *s16; + + d16 = dst; + s16 = src; + + d16[0] = clib_mem_unaligned (&s16[0], u16); + + sum0 = ip_csum_with_carry (sum0, d16[0]); + dst += sizeof (u16); + src += sizeof (u16); + n_left -= sizeof (u16); + } + + sum1 = 0; + while (n_left >= 2 * sizeof (sum)) + { + ip_csum_t dst0, dst1; + ip_csum_t *dst_even, *src_even; + + dst_even = dst; + src_even = src; + dst0 = clib_mem_unaligned (&src_even[0], ip_csum_t); + dst1 = clib_mem_unaligned (&src_even[1], ip_csum_t); + + dst_even[0] = dst0; + dst_even[1] = dst1; + + dst += 2 * sizeof (dst_even[0]); + src += 2 * sizeof (dst_even[0]); + n_left -= 2 * sizeof (dst_even[0]); + + sum0 = ip_csum_with_carry (sum0, dst0); + sum1 = ip_csum_with_carry (sum1, dst1); + } + + sum0 = ip_csum_with_carry (sum0, sum1); + while (n_left >= 1 * sizeof (sum)) + { + ip_csum_t dst0, *dst_even, *src_even; + + dst_even = dst; + src_even = src; + + dst0 = clib_mem_unaligned (&src_even[0], ip_csum_t); + + dst_even[0] = dst0; + + dst += 1 * sizeof (sum); + src += 1 * sizeof (sum); + n_left -= 1 * sizeof (sum); + + sum0 = ip_csum_with_carry (sum0, dst0); + } + + while (n_left >= sizeof (u16)) + { + u16 dst0, *dst_short, *src_short; + + dst_short = dst; + src_short = src; + + dst0 = clib_mem_unaligned (&src_short[0], u16); + + dst_short[0] = dst0; + + sum0 = ip_csum_with_carry (sum0, dst_short[0]); + dst += 1 * sizeof (dst0); + src += 1 * sizeof (dst0); + n_left -= 1 * sizeof (dst0); + + } + + if (n_left == 1) + { + u8 *d8, *s8, val; + + d8 = dst; + s8 = src; + + d8[0] = val = s8[0]; + d8 += 1; + s8 += 1; + n_left -= 1; + sum0 = ip_csum_with_carry (sum0, val << (8 * CLIB_ARCH_IS_BIG_ENDIAN)); + } + + return sum0; +} + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |