drivers/infiniband/sw/rxe/rxe_icrc.c

   1 /*
   2  * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
   3  * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include "rxe.h"
  35 #include "rxe_loc.h"
  36
  37 /* Compute a partial ICRC for all the IB transport headers. */
  38 u32 rxe_icrc_hdr(struct rxe_pkt_info *pkt, struct sk_buff *skb)
  39 {
  40         unsigned int bth_offset = 0;
  41         struct iphdr *ip4h = NULL;
  42         struct ipv6hdr *ip6h = NULL;
  43         struct udphdr *udph;
  44         struct rxe_bth *bth;
  45         int crc;
  46         int length;
  47         int hdr_size = sizeof(struct udphdr) +
  48                 (skb->protocol == htons(ETH_P_IP) ?
  49                 sizeof(struct iphdr) : sizeof(struct ipv6hdr));
  50         /* pseudo header buffer size is calculate using ipv6 header size since
  51          * it is bigger than ipv4
  52          */
  53         u8 pshdr[sizeof(struct udphdr) +
  54                 sizeof(struct ipv6hdr) +
  55                 RXE_BTH_BYTES];
  56
  57         /* This seed is the result of computing a CRC with a seed of
  58          * 0xfffffff and 8 bytes of 0xff representing a masked LRH.
  59          */
  60         crc = 0xdebb20e3;
  61
  62         if (skb->protocol == htons(ETH_P_IP)) { /* IPv4 */
  63                 memcpy(pshdr, ip_hdr(skb), hdr_size);
  64                 ip4h = (struct iphdr *)pshdr;
  65                 udph = (struct udphdr *)(ip4h + 1);
  66
  67                 ip4h->ttl = 0xff;
  68                 ip4h->check = CSUM_MANGLED_0;
  69                 ip4h->tos = 0xff;
  70         } else {                                /* IPv6 */
  71                 memcpy(pshdr, ipv6_hdr(skb), hdr_size);
  72                 ip6h = (struct ipv6hdr *)pshdr;
  73                 udph = (struct udphdr *)(ip6h + 1);
  74
  75                 memset(ip6h->flow_lbl, 0xff, sizeof(ip6h->flow_lbl));
  76                 ip6h->priority = 0xf;
  77                 ip6h->hop_limit = 0xff;
  78         }
  79         udph->check = CSUM_MANGLED_0;
  80
  81         bth_offset += hdr_size;
  82
  83         memcpy(&pshdr[bth_offset], pkt->hdr, RXE_BTH_BYTES);
  84         bth = (struct rxe_bth *)&pshdr[bth_offset];
  85
  86         /* exclude bth.resv8a */
  87         bth->qpn |= cpu_to_be32(~BTH_QPN_MASK);
  88
  89         length = hdr_size + RXE_BTH_BYTES;
  90         crc = rxe_crc32(pkt->rxe, crc, pshdr, length);
  91
  92         /* And finish to compute the CRC on the remainder of the headers. */
  93         crc = rxe_crc32(pkt->rxe, crc, pkt->hdr + RXE_BTH_BYTES,
  94                         rxe_opcode[pkt->opcode].length - RXE_BTH_BYTES);
  95         return crc;
  96 }