176 lines · c
1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB2/*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 <linux/crc32.h>8 9#include "rxe.h"10#include "rxe_loc.h"11 12/**13 * rxe_icrc_init() - Initialize crypto function for computing crc3214 * @rxe: rdma_rxe device object15 *16 * Return: 0 on success else an error17 */18int rxe_icrc_init(struct rxe_dev *rxe)19{20 struct crypto_shash *tfm;21 22 tfm = crypto_alloc_shash("crc32", 0, 0);23 if (IS_ERR(tfm)) {24 rxe_dbg_dev(rxe, "failed to init crc32 algorithm err: %ld\n",25 PTR_ERR(tfm));26 return PTR_ERR(tfm);27 }28 29 rxe->tfm = tfm;30 31 return 0;32}33 34/**35 * rxe_crc32() - Compute cumulative crc32 for a contiguous segment36 * @rxe: rdma_rxe device object37 * @crc: starting crc32 value from previous segments38 * @next: starting address of current segment39 * @len: length of current segment40 *41 * Return: the cumulative crc32 checksum42 */43static __be32 rxe_crc32(struct rxe_dev *rxe, __be32 crc, void *next, size_t len)44{45 __be32 icrc;46 int err;47 48 SHASH_DESC_ON_STACK(shash, rxe->tfm);49 50 shash->tfm = rxe->tfm;51 *(__be32 *)shash_desc_ctx(shash) = crc;52 err = crypto_shash_update(shash, next, len);53 if (unlikely(err)) {54 rxe_dbg_dev(rxe, "failed crc calculation, err: %d\n", err);55 return (__force __be32)crc32_le((__force u32)crc, next, len);56 }57 58 icrc = *(__be32 *)shash_desc_ctx(shash);59 barrier_data(shash_desc_ctx(shash));60 61 return icrc;62}63 64/**65 * rxe_icrc_hdr() - Compute the partial ICRC for the network and transport66 * headers of a packet.67 * @skb: packet buffer68 * @pkt: packet information69 *70 * Return: the partial ICRC71 */72static __be32 rxe_icrc_hdr(struct sk_buff *skb, struct rxe_pkt_info *pkt)73{74 unsigned int bth_offset = 0;75 struct iphdr *ip4h = NULL;76 struct ipv6hdr *ip6h = NULL;77 struct udphdr *udph;78 struct rxe_bth *bth;79 __be32 crc;80 int length;81 int hdr_size = sizeof(struct udphdr) +82 (skb->protocol == htons(ETH_P_IP) ?83 sizeof(struct iphdr) : sizeof(struct ipv6hdr));84 /* pseudo header buffer size is calculate using ipv6 header size since85 * it is bigger than ipv486 */87 u8 pshdr[sizeof(struct udphdr) +88 sizeof(struct ipv6hdr) +89 RXE_BTH_BYTES];90 91 /* This seed is the result of computing a CRC with a seed of92 * 0xfffffff and 8 bytes of 0xff representing a masked LRH.93 */94 crc = (__force __be32)0xdebb20e3;95 96 if (skb->protocol == htons(ETH_P_IP)) { /* IPv4 */97 memcpy(pshdr, ip_hdr(skb), hdr_size);98 ip4h = (struct iphdr *)pshdr;99 udph = (struct udphdr *)(ip4h + 1);100 101 ip4h->ttl = 0xff;102 ip4h->check = CSUM_MANGLED_0;103 ip4h->tos = 0xff;104 } else { /* IPv6 */105 memcpy(pshdr, ipv6_hdr(skb), hdr_size);106 ip6h = (struct ipv6hdr *)pshdr;107 udph = (struct udphdr *)(ip6h + 1);108 109 memset(ip6h->flow_lbl, 0xff, sizeof(ip6h->flow_lbl));110 ip6h->priority = 0xf;111 ip6h->hop_limit = 0xff;112 }113 udph->check = CSUM_MANGLED_0;114 115 bth_offset += hdr_size;116 117 memcpy(&pshdr[bth_offset], pkt->hdr, RXE_BTH_BYTES);118 bth = (struct rxe_bth *)&pshdr[bth_offset];119 120 /* exclude bth.resv8a */121 bth->qpn |= cpu_to_be32(~BTH_QPN_MASK);122 123 length = hdr_size + RXE_BTH_BYTES;124 crc = rxe_crc32(pkt->rxe, crc, pshdr, length);125 126 /* And finish to compute the CRC on the remainder of the headers. */127 crc = rxe_crc32(pkt->rxe, crc, pkt->hdr + RXE_BTH_BYTES,128 rxe_opcode[pkt->opcode].length - RXE_BTH_BYTES);129 return crc;130}131 132/**133 * rxe_icrc_check() - Compute ICRC for a packet and compare to the ICRC134 * delivered in the packet.135 * @skb: packet buffer136 * @pkt: packet information137 *138 * Return: 0 if the values match else an error139 */140int rxe_icrc_check(struct sk_buff *skb, struct rxe_pkt_info *pkt)141{142 __be32 *icrcp;143 __be32 pkt_icrc;144 __be32 icrc;145 146 icrcp = (__be32 *)(pkt->hdr + pkt->paylen - RXE_ICRC_SIZE);147 pkt_icrc = *icrcp;148 149 icrc = rxe_icrc_hdr(skb, pkt);150 icrc = rxe_crc32(pkt->rxe, icrc, (u8 *)payload_addr(pkt),151 payload_size(pkt) + bth_pad(pkt));152 icrc = ~icrc;153 154 if (unlikely(icrc != pkt_icrc))155 return -EINVAL;156 157 return 0;158}159 160/**161 * rxe_icrc_generate() - compute ICRC for a packet.162 * @skb: packet buffer163 * @pkt: packet information164 */165void rxe_icrc_generate(struct sk_buff *skb, struct rxe_pkt_info *pkt)166{167 __be32 *icrcp;168 __be32 icrc;169 170 icrcp = (__be32 *)(pkt->hdr + pkt->paylen - RXE_ICRC_SIZE);171 icrc = rxe_icrc_hdr(skb, pkt);172 icrc = rxe_crc32(pkt->rxe, icrc, (u8 *)payload_addr(pkt),173 payload_size(pkt) + bth_pad(pkt));174 *icrcp = ~icrc;175}176