1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB 2 /* 3 * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved. 4 * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved. 5 */ 6 7 #include "rxe.h" 8 #include "rxe_loc.h" 9 10 /* Compute a partial ICRC for all the IB transport headers. */ 11 u32 rxe_icrc_hdr(struct rxe_pkt_info *pkt, struct sk_buff *skb) 12 { 13 unsigned int bth_offset = 0; 14 struct iphdr *ip4h = NULL; 15 struct ipv6hdr *ip6h = NULL; 16 struct udphdr *udph; 17 struct rxe_bth *bth; 18 int crc; 19 int length; 20 int hdr_size = sizeof(struct udphdr) + 21 (skb->protocol == htons(ETH_P_IP) ? 22 sizeof(struct iphdr) : sizeof(struct ipv6hdr)); 23 /* pseudo header buffer size is calculate using ipv6 header size since 24 * it is bigger than ipv4 25 */ 26 u8 pshdr[sizeof(struct udphdr) + 27 sizeof(struct ipv6hdr) + 28 RXE_BTH_BYTES]; 29 30 /* This seed is the result of computing a CRC with a seed of 31 * 0xfffffff and 8 bytes of 0xff representing a masked LRH. 32 */ 33 crc = 0xdebb20e3; 34 35 if (skb->protocol == htons(ETH_P_IP)) { /* IPv4 */ 36 memcpy(pshdr, ip_hdr(skb), hdr_size); 37 ip4h = (struct iphdr *)pshdr; 38 udph = (struct udphdr *)(ip4h + 1); 39 40 ip4h->ttl = 0xff; 41 ip4h->check = CSUM_MANGLED_0; 42 ip4h->tos = 0xff; 43 } else { /* IPv6 */ 44 memcpy(pshdr, ipv6_hdr(skb), hdr_size); 45 ip6h = (struct ipv6hdr *)pshdr; 46 udph = (struct udphdr *)(ip6h + 1); 47 48 memset(ip6h->flow_lbl, 0xff, sizeof(ip6h->flow_lbl)); 49 ip6h->priority = 0xf; 50 ip6h->hop_limit = 0xff; 51 } 52 udph->check = CSUM_MANGLED_0; 53 54 bth_offset += hdr_size; 55 56 memcpy(&pshdr[bth_offset], pkt->hdr, RXE_BTH_BYTES); 57 bth = (struct rxe_bth *)&pshdr[bth_offset]; 58 59 /* exclude bth.resv8a */ 60 bth->qpn |= cpu_to_be32(~BTH_QPN_MASK); 61 62 length = hdr_size + RXE_BTH_BYTES; 63 crc = rxe_crc32(pkt->rxe, crc, pshdr, length); 64 65 /* And finish to compute the CRC on the remainder of the headers. */ 66 crc = rxe_crc32(pkt->rxe, crc, pkt->hdr + RXE_BTH_BYTES, 67 rxe_opcode[pkt->opcode].length - RXE_BTH_BYTES); 68 return crc; 69 } 70