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Diffstat (limited to 'vnet/vnet/ip/ip_packet.h')
| -rw-r--r-- | vnet/vnet/ip/ip_packet.h | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/vnet/vnet/ip/ip_packet.h b/vnet/vnet/ip/ip_packet.h new file mode 100644 index 00000000000..fb9a23604e1 --- /dev/null +++ b/vnet/vnet/ip/ip_packet.h @@ -0,0 +1,183 @@ +/* + * 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. + */ +/* + * ip/ip_packet.h: packet format common between ip4 & ip6 + * + * 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. + */ + +#ifndef included_ip_packet_h +#define included_ip_packet_h + +#include <vppinfra/byte_order.h> +#include <vppinfra/error.h> + +typedef enum ip_protocol { +#define ip_protocol(n,s) IP_PROTOCOL_##s = n, +#include "protocols.def" +#undef ip_protocol +} ip_protocol_t; + +/* TCP/UDP ports. */ +typedef enum { +#define ip_port(s,n) IP_PORT_##s = n, +#include "ports.def" +#undef ip_port +} ip_port_t; + +/* Classifies protocols into TCP, UDP, ICMP or other. */ +typedef enum { + IP_BUILTIN_PROTOCOL_UDP, + IP_BUILTIN_PROTOCOL_TCP, + IP_BUILTIN_PROTOCOL_ICMP, + IP_BUILTIN_PROTOCOL_UNKNOWN, +} ip_builtin_protocol_t; + +#define foreach_ip_builtin_multicast_group \ + _ (1, all_hosts_on_subnet) \ + _ (2, all_routers_on_subnet) \ + _ (4, dvmrp) \ + _ (5, ospf_all_routers) \ + _ (6, ospf_designated_routers) \ + _ (13, pim) \ + _ (18, vrrp) \ + _ (102, hsrp) \ + _ (22, igmp_v3) + +typedef enum { +#define _(n,f) IP_MULTICAST_GROUP_##f = n, + foreach_ip_builtin_multicast_group +#undef _ +} ip_multicast_group_t; + +/* IP checksum support. */ + +/* Incremental checksum update. */ +typedef uword ip_csum_t; + +always_inline ip_csum_t +ip_csum_with_carry (ip_csum_t sum, ip_csum_t x) +{ + ip_csum_t t = sum + x; + return t + (t < x); +} + +/* Update checksum changing field at even byte offset from x -> 0. */ +always_inline ip_csum_t +ip_csum_add_even (ip_csum_t c, ip_csum_t x) +{ + ip_csum_t d; + + d = c - x; + + /* Fold in carry from high bit. */ + d -= d > c; + + ASSERT (ip_csum_with_carry (d, x) == c); + + return d; +} + +/* Update checksum changing field at even byte offset from 0 -> x. */ +always_inline ip_csum_t +ip_csum_sub_even (ip_csum_t c, ip_csum_t x) +{ return ip_csum_with_carry (c, x); } + +always_inline ip_csum_t +ip_csum_update_inline (ip_csum_t sum, ip_csum_t old, ip_csum_t new, + u32 field_byte_offset, u32 field_n_bytes) +{ + /* For even 1-byte fields on big-endian and odd 1-byte fields on little endian + we need to shift byte into place for checksum. */ + if ((field_n_bytes % 2) + && (field_byte_offset % 2) == CLIB_ARCH_IS_LITTLE_ENDIAN) + { + old = old << 8; + new = new << 8; + } + sum = ip_csum_sub_even (sum, old); + sum = ip_csum_add_even (sum, new); + return sum; +} + +#define ip_csum_update(sum,old,new,type,field) \ + ip_csum_update_inline ((sum), (old), (new), \ + STRUCT_OFFSET_OF (type, field), \ + STRUCT_SIZE_OF (type, field)) + +always_inline u16 ip_csum_fold (ip_csum_t c) +{ + /* Reduce to 16 bits. */ +#if uword_bits == 64 + c = (c & (ip_csum_t) 0xffffffff) + (c >> (ip_csum_t) 32); + c = (c & 0xffff) + (c >> 16); +#endif + + c = (c & 0xffff) + (c >> 16); + c = (c & 0xffff) + (c >> 16); + + return c; +} + +/* Copy data and checksum at the same time. */ +ip_csum_t ip_csum_and_memcpy (ip_csum_t sum, void * dst, void * src, uword n_bytes); + +always_inline u16 +ip_csum_and_memcpy_fold (ip_csum_t sum, void * dst) +{ + uword n_zero; + ip_csum_t * dst_even; + + dst_even = uword_to_pointer + (pointer_to_uword (dst) &~ (sizeof (sum) - 1), + ip_csum_t *); + + if ((n_zero = dst - (void *) dst_even)) + { + u8 * d8 = dst; + uword i; + + for (i = 0; i < n_zero; i++) + d8[i] = 0; + + sum = ip_csum_with_carry (sum, dst_even[0]); + } + + return ip_csum_fold (sum); +} + +/* Checksum routine. */ +ip_csum_t ip_incremental_checksum (ip_csum_t sum, void * data, uword n_bytes); + +#endif /* included_ip_packet_h */ |