/* * 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: */