197fb5e8dSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 2e1d9a90aSSharath Chandra Vurukala /* Copyright (c) 2013-2018, 2021, The Linux Foundation. All rights reserved. 3ceed73a2SSubash Abhinov Kasiviswanathan * 4ceed73a2SSubash Abhinov Kasiviswanathan * RMNET Data MAP protocol 5ceed73a2SSubash Abhinov Kasiviswanathan */ 6ceed73a2SSubash Abhinov Kasiviswanathan 7ceed73a2SSubash Abhinov Kasiviswanathan #include <linux/netdevice.h> 8bbd21b24SSubash Abhinov Kasiviswanathan #include <linux/ip.h> 9bbd21b24SSubash Abhinov Kasiviswanathan #include <linux/ipv6.h> 10bbd21b24SSubash Abhinov Kasiviswanathan #include <net/ip6_checksum.h> 11e1d9a90aSSharath Chandra Vurukala #include <linux/bitfield.h> 12ceed73a2SSubash Abhinov Kasiviswanathan #include "rmnet_config.h" 13ceed73a2SSubash Abhinov Kasiviswanathan #include "rmnet_map.h" 14ceed73a2SSubash Abhinov Kasiviswanathan #include "rmnet_private.h" 15ceed73a2SSubash Abhinov Kasiviswanathan 16ceed73a2SSubash Abhinov Kasiviswanathan #define RMNET_MAP_DEAGGR_SPACING 64 17ceed73a2SSubash Abhinov Kasiviswanathan #define RMNET_MAP_DEAGGR_HEADROOM (RMNET_MAP_DEAGGR_SPACING / 2) 18ceed73a2SSubash Abhinov Kasiviswanathan 19bbd21b24SSubash Abhinov Kasiviswanathan static __sum16 *rmnet_map_get_csum_field(unsigned char protocol, 20bbd21b24SSubash Abhinov Kasiviswanathan const void *txporthdr) 21bbd21b24SSubash Abhinov Kasiviswanathan { 22bbd21b24SSubash Abhinov Kasiviswanathan __sum16 *check = NULL; 23bbd21b24SSubash Abhinov Kasiviswanathan 24bbd21b24SSubash Abhinov Kasiviswanathan switch (protocol) { 25bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_TCP: 26bbd21b24SSubash Abhinov Kasiviswanathan check = &(((struct tcphdr *)txporthdr)->check); 27bbd21b24SSubash Abhinov Kasiviswanathan break; 28bbd21b24SSubash Abhinov Kasiviswanathan 29bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_UDP: 30bbd21b24SSubash Abhinov Kasiviswanathan check = &(((struct udphdr *)txporthdr)->check); 31bbd21b24SSubash Abhinov Kasiviswanathan break; 32bbd21b24SSubash Abhinov Kasiviswanathan 33bbd21b24SSubash Abhinov Kasiviswanathan default: 34bbd21b24SSubash Abhinov Kasiviswanathan check = NULL; 35bbd21b24SSubash Abhinov Kasiviswanathan break; 36bbd21b24SSubash Abhinov Kasiviswanathan } 37bbd21b24SSubash Abhinov Kasiviswanathan 38bbd21b24SSubash Abhinov Kasiviswanathan return check; 39bbd21b24SSubash Abhinov Kasiviswanathan } 40bbd21b24SSubash Abhinov Kasiviswanathan 41bbd21b24SSubash Abhinov Kasiviswanathan static int 42bbd21b24SSubash Abhinov Kasiviswanathan rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb, 43bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_map_dl_csum_trailer *csum_trailer, 44bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv) 45bbd21b24SSubash Abhinov Kasiviswanathan { 46bbd21b24SSubash Abhinov Kasiviswanathan __sum16 *csum_field, csum_temp, pseudo_csum, hdr_csum, ip_payload_csum; 47bbd21b24SSubash Abhinov Kasiviswanathan u16 csum_value, csum_value_final; 48bbd21b24SSubash Abhinov Kasiviswanathan struct iphdr *ip4h; 49bbd21b24SSubash Abhinov Kasiviswanathan void *txporthdr; 50bbd21b24SSubash Abhinov Kasiviswanathan __be16 addend; 51bbd21b24SSubash Abhinov Kasiviswanathan 52bbd21b24SSubash Abhinov Kasiviswanathan ip4h = (struct iphdr *)(skb->data); 53e4517d8aSAlex Elder 54e4517d8aSAlex Elder /* We don't support checksum offload on IPv4 fragments */ 55e4517d8aSAlex Elder if (ip_is_fragment(ip4h)) { 56bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_fragmented_pkt++; 57bbd21b24SSubash Abhinov Kasiviswanathan return -EOPNOTSUPP; 58bbde32d3SSubash Abhinov Kasiviswanathan } 59bbd21b24SSubash Abhinov Kasiviswanathan 60bbd21b24SSubash Abhinov Kasiviswanathan txporthdr = skb->data + ip4h->ihl * 4; 61bbd21b24SSubash Abhinov Kasiviswanathan 62bbd21b24SSubash Abhinov Kasiviswanathan csum_field = rmnet_map_get_csum_field(ip4h->protocol, txporthdr); 63bbd21b24SSubash Abhinov Kasiviswanathan 64bbde32d3SSubash Abhinov Kasiviswanathan if (!csum_field) { 65bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_transport++; 66bbd21b24SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 67bbde32d3SSubash Abhinov Kasiviswanathan } 68bbd21b24SSubash Abhinov Kasiviswanathan 69bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 768 - Skip IPv4 UDP packets where sender checksum field is 0 */ 70bbde32d3SSubash Abhinov Kasiviswanathan if (*csum_field == 0 && ip4h->protocol == IPPROTO_UDP) { 71bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_skipped++; 72bbd21b24SSubash Abhinov Kasiviswanathan return 0; 73bbde32d3SSubash Abhinov Kasiviswanathan } 74bbd21b24SSubash Abhinov Kasiviswanathan 75bbd21b24SSubash Abhinov Kasiviswanathan csum_value = ~ntohs(csum_trailer->csum_value); 76bbd21b24SSubash Abhinov Kasiviswanathan hdr_csum = ~ip_fast_csum(ip4h, (int)ip4h->ihl); 77bbd21b24SSubash Abhinov Kasiviswanathan ip_payload_csum = csum16_sub((__force __sum16)csum_value, 78bbd21b24SSubash Abhinov Kasiviswanathan (__force __be16)hdr_csum); 79bbd21b24SSubash Abhinov Kasiviswanathan 80bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = ~csum_tcpudp_magic(ip4h->saddr, ip4h->daddr, 81bbd21b24SSubash Abhinov Kasiviswanathan ntohs(ip4h->tot_len) - ip4h->ihl * 4, 82bbd21b24SSubash Abhinov Kasiviswanathan ip4h->protocol, 0); 83bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)pseudo_csum); 84bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = csum16_add(ip_payload_csum, addend); 85bbd21b24SSubash Abhinov Kasiviswanathan 86bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)*csum_field); 87bbd21b24SSubash Abhinov Kasiviswanathan csum_temp = ~csum16_sub(pseudo_csum, addend); 88bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = (__force u16)csum_temp; 89bbd21b24SSubash Abhinov Kasiviswanathan 90bbd21b24SSubash Abhinov Kasiviswanathan if (unlikely(csum_value_final == 0)) { 91bbd21b24SSubash Abhinov Kasiviswanathan switch (ip4h->protocol) { 92bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_UDP: 93bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 768 - DL4 1's complement rule for UDP csum 0 */ 94bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 95bbd21b24SSubash Abhinov Kasiviswanathan break; 96bbd21b24SSubash Abhinov Kasiviswanathan 97bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_TCP: 98bbd21b24SSubash Abhinov Kasiviswanathan /* DL4 Non-RFC compliant TCP checksum found */ 99bbd21b24SSubash Abhinov Kasiviswanathan if (*csum_field == (__force __sum16)0xFFFF) 100bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 101bbd21b24SSubash Abhinov Kasiviswanathan break; 102bbd21b24SSubash Abhinov Kasiviswanathan } 103bbd21b24SSubash Abhinov Kasiviswanathan } 104bbd21b24SSubash Abhinov Kasiviswanathan 105bbde32d3SSubash Abhinov Kasiviswanathan if (csum_value_final == ntohs((__force __be16)*csum_field)) { 106bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_ok++; 107bbd21b24SSubash Abhinov Kasiviswanathan return 0; 108bbde32d3SSubash Abhinov Kasiviswanathan } else { 109bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_validation_failed++; 110bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 111bbd21b24SSubash Abhinov Kasiviswanathan } 112bbde32d3SSubash Abhinov Kasiviswanathan } 113bbd21b24SSubash Abhinov Kasiviswanathan 114bbd21b24SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 115bbd21b24SSubash Abhinov Kasiviswanathan static int 116bbd21b24SSubash Abhinov Kasiviswanathan rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, 117bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_map_dl_csum_trailer *csum_trailer, 118bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv) 119bbd21b24SSubash Abhinov Kasiviswanathan { 120bbd21b24SSubash Abhinov Kasiviswanathan __sum16 *csum_field, ip6_payload_csum, pseudo_csum, csum_temp; 121bbd21b24SSubash Abhinov Kasiviswanathan u16 csum_value, csum_value_final; 122bbd21b24SSubash Abhinov Kasiviswanathan __be16 ip6_hdr_csum, addend; 123bbd21b24SSubash Abhinov Kasiviswanathan struct ipv6hdr *ip6h; 124bbd21b24SSubash Abhinov Kasiviswanathan void *txporthdr; 125bbd21b24SSubash Abhinov Kasiviswanathan u32 length; 126bbd21b24SSubash Abhinov Kasiviswanathan 127bbd21b24SSubash Abhinov Kasiviswanathan ip6h = (struct ipv6hdr *)(skb->data); 128bbd21b24SSubash Abhinov Kasiviswanathan 129bbd21b24SSubash Abhinov Kasiviswanathan txporthdr = skb->data + sizeof(struct ipv6hdr); 130bbd21b24SSubash Abhinov Kasiviswanathan csum_field = rmnet_map_get_csum_field(ip6h->nexthdr, txporthdr); 131bbd21b24SSubash Abhinov Kasiviswanathan 132bbde32d3SSubash Abhinov Kasiviswanathan if (!csum_field) { 133bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_transport++; 134bbd21b24SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 135bbde32d3SSubash Abhinov Kasiviswanathan } 136bbd21b24SSubash Abhinov Kasiviswanathan 137bbd21b24SSubash Abhinov Kasiviswanathan csum_value = ~ntohs(csum_trailer->csum_value); 138bbd21b24SSubash Abhinov Kasiviswanathan ip6_hdr_csum = (__force __be16) 139bbd21b24SSubash Abhinov Kasiviswanathan ~ntohs((__force __be16)ip_compute_csum(ip6h, 140bbd21b24SSubash Abhinov Kasiviswanathan (int)(txporthdr - (void *)(skb->data)))); 141bbd21b24SSubash Abhinov Kasiviswanathan ip6_payload_csum = csum16_sub((__force __sum16)csum_value, 142bbd21b24SSubash Abhinov Kasiviswanathan ip6_hdr_csum); 143bbd21b24SSubash Abhinov Kasiviswanathan 144bbd21b24SSubash Abhinov Kasiviswanathan length = (ip6h->nexthdr == IPPROTO_UDP) ? 145bbd21b24SSubash Abhinov Kasiviswanathan ntohs(((struct udphdr *)txporthdr)->len) : 146bbd21b24SSubash Abhinov Kasiviswanathan ntohs(ip6h->payload_len); 147bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = ~(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, 148bbd21b24SSubash Abhinov Kasiviswanathan length, ip6h->nexthdr, 0)); 149bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)pseudo_csum); 150bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = csum16_add(ip6_payload_csum, addend); 151bbd21b24SSubash Abhinov Kasiviswanathan 152bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)*csum_field); 153bbd21b24SSubash Abhinov Kasiviswanathan csum_temp = ~csum16_sub(pseudo_csum, addend); 154bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = (__force u16)csum_temp; 155bbd21b24SSubash Abhinov Kasiviswanathan 156bbd21b24SSubash Abhinov Kasiviswanathan if (unlikely(csum_value_final == 0)) { 157bbd21b24SSubash Abhinov Kasiviswanathan switch (ip6h->nexthdr) { 158bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_UDP: 159bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 2460 section 8.1 160bbd21b24SSubash Abhinov Kasiviswanathan * DL6 One's complement rule for UDP checksum 0 161bbd21b24SSubash Abhinov Kasiviswanathan */ 162bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 163bbd21b24SSubash Abhinov Kasiviswanathan break; 164bbd21b24SSubash Abhinov Kasiviswanathan 165bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_TCP: 166bbd21b24SSubash Abhinov Kasiviswanathan /* DL6 Non-RFC compliant TCP checksum found */ 167bbd21b24SSubash Abhinov Kasiviswanathan if (*csum_field == (__force __sum16)0xFFFF) 168bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 169bbd21b24SSubash Abhinov Kasiviswanathan break; 170bbd21b24SSubash Abhinov Kasiviswanathan } 171bbd21b24SSubash Abhinov Kasiviswanathan } 172bbd21b24SSubash Abhinov Kasiviswanathan 173bbde32d3SSubash Abhinov Kasiviswanathan if (csum_value_final == ntohs((__force __be16)*csum_field)) { 174bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_ok++; 175bbd21b24SSubash Abhinov Kasiviswanathan return 0; 176bbde32d3SSubash Abhinov Kasiviswanathan } else { 177bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_validation_failed++; 178bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 179bbd21b24SSubash Abhinov Kasiviswanathan } 180bbde32d3SSubash Abhinov Kasiviswanathan } 181bbd21b24SSubash Abhinov Kasiviswanathan #endif 182bbd21b24SSubash Abhinov Kasiviswanathan 1835eb5f860SSubash Abhinov Kasiviswanathan static void rmnet_map_complement_ipv4_txporthdr_csum_field(void *iphdr) 1845eb5f860SSubash Abhinov Kasiviswanathan { 1855eb5f860SSubash Abhinov Kasiviswanathan struct iphdr *ip4h = (struct iphdr *)iphdr; 1865eb5f860SSubash Abhinov Kasiviswanathan void *txphdr; 1875eb5f860SSubash Abhinov Kasiviswanathan u16 *csum; 1885eb5f860SSubash Abhinov Kasiviswanathan 1895eb5f860SSubash Abhinov Kasiviswanathan txphdr = iphdr + ip4h->ihl * 4; 1905eb5f860SSubash Abhinov Kasiviswanathan 1915eb5f860SSubash Abhinov Kasiviswanathan if (ip4h->protocol == IPPROTO_TCP || ip4h->protocol == IPPROTO_UDP) { 1925eb5f860SSubash Abhinov Kasiviswanathan csum = (u16 *)rmnet_map_get_csum_field(ip4h->protocol, txphdr); 1935eb5f860SSubash Abhinov Kasiviswanathan *csum = ~(*csum); 1945eb5f860SSubash Abhinov Kasiviswanathan } 1955eb5f860SSubash Abhinov Kasiviswanathan } 1965eb5f860SSubash Abhinov Kasiviswanathan 1975eb5f860SSubash Abhinov Kasiviswanathan static void 198*1d257f45SAlex Elder rmnet_map_ipv4_ul_csum_header(struct iphdr *iphdr, 1995eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header, 2005eb5f860SSubash Abhinov Kasiviswanathan struct sk_buff *skb) 2015eb5f860SSubash Abhinov Kasiviswanathan { 20286ca860eSAlex Elder u16 val; 20386ca860eSAlex Elder 20486ca860eSAlex Elder val = MAP_CSUM_UL_ENABLED_FLAG; 205*1d257f45SAlex Elder if (iphdr->protocol == IPPROTO_UDP) 20686ca860eSAlex Elder val |= MAP_CSUM_UL_UDP_FLAG; 20786ca860eSAlex Elder val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK; 2085eb5f860SSubash Abhinov Kasiviswanathan 20950c62a11SAlex Elder ul_header->csum_start_offset = htons(skb_network_header_len(skb)); 21086ca860eSAlex Elder ul_header->csum_info = htons(val); 2115eb5f860SSubash Abhinov Kasiviswanathan 2125eb5f860SSubash Abhinov Kasiviswanathan skb->ip_summed = CHECKSUM_NONE; 2135eb5f860SSubash Abhinov Kasiviswanathan 2145eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_complement_ipv4_txporthdr_csum_field(iphdr); 2155eb5f860SSubash Abhinov Kasiviswanathan } 2165eb5f860SSubash Abhinov Kasiviswanathan 2175eb5f860SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 2185eb5f860SSubash Abhinov Kasiviswanathan static void rmnet_map_complement_ipv6_txporthdr_csum_field(void *ip6hdr) 2195eb5f860SSubash Abhinov Kasiviswanathan { 2205eb5f860SSubash Abhinov Kasiviswanathan struct ipv6hdr *ip6h = (struct ipv6hdr *)ip6hdr; 2215eb5f860SSubash Abhinov Kasiviswanathan void *txphdr; 2225eb5f860SSubash Abhinov Kasiviswanathan u16 *csum; 2235eb5f860SSubash Abhinov Kasiviswanathan 2245eb5f860SSubash Abhinov Kasiviswanathan txphdr = ip6hdr + sizeof(struct ipv6hdr); 2255eb5f860SSubash Abhinov Kasiviswanathan 2265eb5f860SSubash Abhinov Kasiviswanathan if (ip6h->nexthdr == IPPROTO_TCP || ip6h->nexthdr == IPPROTO_UDP) { 2275eb5f860SSubash Abhinov Kasiviswanathan csum = (u16 *)rmnet_map_get_csum_field(ip6h->nexthdr, txphdr); 2285eb5f860SSubash Abhinov Kasiviswanathan *csum = ~(*csum); 2295eb5f860SSubash Abhinov Kasiviswanathan } 2305eb5f860SSubash Abhinov Kasiviswanathan } 2315eb5f860SSubash Abhinov Kasiviswanathan 2325eb5f860SSubash Abhinov Kasiviswanathan static void 233*1d257f45SAlex Elder rmnet_map_ipv6_ul_csum_header(struct ipv6hdr *ipv6hdr, 2345eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header, 2355eb5f860SSubash Abhinov Kasiviswanathan struct sk_buff *skb) 2365eb5f860SSubash Abhinov Kasiviswanathan { 23786ca860eSAlex Elder u16 val; 23886ca860eSAlex Elder 23986ca860eSAlex Elder val = MAP_CSUM_UL_ENABLED_FLAG; 240*1d257f45SAlex Elder if (ipv6hdr->nexthdr == IPPROTO_UDP) 24186ca860eSAlex Elder val |= MAP_CSUM_UL_UDP_FLAG; 24286ca860eSAlex Elder val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK; 2435eb5f860SSubash Abhinov Kasiviswanathan 24450c62a11SAlex Elder ul_header->csum_start_offset = htons(skb_network_header_len(skb)); 24586ca860eSAlex Elder ul_header->csum_info = htons(val); 2465eb5f860SSubash Abhinov Kasiviswanathan 2475eb5f860SSubash Abhinov Kasiviswanathan skb->ip_summed = CHECKSUM_NONE; 2485eb5f860SSubash Abhinov Kasiviswanathan 249*1d257f45SAlex Elder rmnet_map_complement_ipv6_txporthdr_csum_field(ipv6hdr); 2505eb5f860SSubash Abhinov Kasiviswanathan } 2515eb5f860SSubash Abhinov Kasiviswanathan #endif 2525eb5f860SSubash Abhinov Kasiviswanathan 253b6e5d27eSSharath Chandra Vurukala static void rmnet_map_v5_checksum_uplink_packet(struct sk_buff *skb, 254b6e5d27eSSharath Chandra Vurukala struct rmnet_port *port, 255b6e5d27eSSharath Chandra Vurukala struct net_device *orig_dev) 256b6e5d27eSSharath Chandra Vurukala { 257b6e5d27eSSharath Chandra Vurukala struct rmnet_priv *priv = netdev_priv(orig_dev); 258b6e5d27eSSharath Chandra Vurukala struct rmnet_map_v5_csum_header *ul_header; 259b6e5d27eSSharath Chandra Vurukala 260b6e5d27eSSharath Chandra Vurukala ul_header = skb_push(skb, sizeof(*ul_header)); 261b6e5d27eSSharath Chandra Vurukala memset(ul_header, 0, sizeof(*ul_header)); 262b6e5d27eSSharath Chandra Vurukala ul_header->header_info = u8_encode_bits(RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD, 263b6e5d27eSSharath Chandra Vurukala MAPV5_HDRINFO_HDR_TYPE_FMASK); 264b6e5d27eSSharath Chandra Vurukala 265b6e5d27eSSharath Chandra Vurukala if (skb->ip_summed == CHECKSUM_PARTIAL) { 266b6e5d27eSSharath Chandra Vurukala void *iph = ip_hdr(skb); 267b6e5d27eSSharath Chandra Vurukala __sum16 *check; 268b6e5d27eSSharath Chandra Vurukala void *trans; 269b6e5d27eSSharath Chandra Vurukala u8 proto; 270b6e5d27eSSharath Chandra Vurukala 271b6e5d27eSSharath Chandra Vurukala if (skb->protocol == htons(ETH_P_IP)) { 272b6e5d27eSSharath Chandra Vurukala u16 ip_len = ((struct iphdr *)iph)->ihl * 4; 273b6e5d27eSSharath Chandra Vurukala 274b6e5d27eSSharath Chandra Vurukala proto = ((struct iphdr *)iph)->protocol; 275b6e5d27eSSharath Chandra Vurukala trans = iph + ip_len; 276118de610SNathan Chancellor } else if (IS_ENABLED(CONFIG_IPV6) && 277118de610SNathan Chancellor skb->protocol == htons(ETH_P_IPV6)) { 278b6e5d27eSSharath Chandra Vurukala u16 ip_len = sizeof(struct ipv6hdr); 279b6e5d27eSSharath Chandra Vurukala 280b6e5d27eSSharath Chandra Vurukala proto = ((struct ipv6hdr *)iph)->nexthdr; 281b6e5d27eSSharath Chandra Vurukala trans = iph + ip_len; 282118de610SNathan Chancellor } else { 283b6e5d27eSSharath Chandra Vurukala priv->stats.csum_err_invalid_ip_version++; 284b6e5d27eSSharath Chandra Vurukala goto sw_csum; 285b6e5d27eSSharath Chandra Vurukala } 286b6e5d27eSSharath Chandra Vurukala 287b6e5d27eSSharath Chandra Vurukala check = rmnet_map_get_csum_field(proto, trans); 288b6e5d27eSSharath Chandra Vurukala if (check) { 289b6e5d27eSSharath Chandra Vurukala skb->ip_summed = CHECKSUM_NONE; 290b6e5d27eSSharath Chandra Vurukala /* Ask for checksum offloading */ 291b6e5d27eSSharath Chandra Vurukala ul_header->csum_info |= MAPV5_CSUMINFO_VALID_FLAG; 292b6e5d27eSSharath Chandra Vurukala priv->stats.csum_hw++; 293b6e5d27eSSharath Chandra Vurukala return; 294b6e5d27eSSharath Chandra Vurukala } 295b6e5d27eSSharath Chandra Vurukala } 296b6e5d27eSSharath Chandra Vurukala 297b6e5d27eSSharath Chandra Vurukala sw_csum: 298b6e5d27eSSharath Chandra Vurukala priv->stats.csum_sw++; 299b6e5d27eSSharath Chandra Vurukala } 300b6e5d27eSSharath Chandra Vurukala 301ceed73a2SSubash Abhinov Kasiviswanathan /* Adds MAP header to front of skb->data 302ceed73a2SSubash Abhinov Kasiviswanathan * Padding is calculated and set appropriately in MAP header. Mux ID is 303ceed73a2SSubash Abhinov Kasiviswanathan * initialized to 0. 304ceed73a2SSubash Abhinov Kasiviswanathan */ 305ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb, 306b6e5d27eSSharath Chandra Vurukala int hdrlen, 307b6e5d27eSSharath Chandra Vurukala struct rmnet_port *port, 308b6e5d27eSSharath Chandra Vurukala int pad) 309ceed73a2SSubash Abhinov Kasiviswanathan { 310ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *map_header; 311ceed73a2SSubash Abhinov Kasiviswanathan u32 padding, map_datalen; 312ceed73a2SSubash Abhinov Kasiviswanathan u8 *padbytes; 313ceed73a2SSubash Abhinov Kasiviswanathan 314ceed73a2SSubash Abhinov Kasiviswanathan map_datalen = skb->len - hdrlen; 315ceed73a2SSubash Abhinov Kasiviswanathan map_header = (struct rmnet_map_header *) 316ceed73a2SSubash Abhinov Kasiviswanathan skb_push(skb, sizeof(struct rmnet_map_header)); 317ceed73a2SSubash Abhinov Kasiviswanathan memset(map_header, 0, sizeof(struct rmnet_map_header)); 318ceed73a2SSubash Abhinov Kasiviswanathan 319b6e5d27eSSharath Chandra Vurukala /* Set next_hdr bit for csum offload packets */ 320b6e5d27eSSharath Chandra Vurukala if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV5) 321b6e5d27eSSharath Chandra Vurukala map_header->flags |= MAP_NEXT_HEADER_FLAG; 322b6e5d27eSSharath Chandra Vurukala 323ceed73a2SSubash Abhinov Kasiviswanathan if (pad == RMNET_MAP_NO_PAD_BYTES) { 324ceed73a2SSubash Abhinov Kasiviswanathan map_header->pkt_len = htons(map_datalen); 325ceed73a2SSubash Abhinov Kasiviswanathan return map_header; 326ceed73a2SSubash Abhinov Kasiviswanathan } 327ceed73a2SSubash Abhinov Kasiviswanathan 32816653c16SAlex Elder BUILD_BUG_ON(MAP_PAD_LEN_MASK < 3); 329ceed73a2SSubash Abhinov Kasiviswanathan padding = ALIGN(map_datalen, 4) - map_datalen; 330ceed73a2SSubash Abhinov Kasiviswanathan 331ceed73a2SSubash Abhinov Kasiviswanathan if (padding == 0) 332ceed73a2SSubash Abhinov Kasiviswanathan goto done; 333ceed73a2SSubash Abhinov Kasiviswanathan 334ceed73a2SSubash Abhinov Kasiviswanathan if (skb_tailroom(skb) < padding) 335ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 336ceed73a2SSubash Abhinov Kasiviswanathan 337ceed73a2SSubash Abhinov Kasiviswanathan padbytes = (u8 *)skb_put(skb, padding); 338ceed73a2SSubash Abhinov Kasiviswanathan memset(padbytes, 0, padding); 339ceed73a2SSubash Abhinov Kasiviswanathan 340ceed73a2SSubash Abhinov Kasiviswanathan done: 341ceed73a2SSubash Abhinov Kasiviswanathan map_header->pkt_len = htons(map_datalen + padding); 34216653c16SAlex Elder /* This is a data packet, so the CMD bit is 0 */ 34316653c16SAlex Elder map_header->flags = padding & MAP_PAD_LEN_MASK; 344ceed73a2SSubash Abhinov Kasiviswanathan 345ceed73a2SSubash Abhinov Kasiviswanathan return map_header; 346ceed73a2SSubash Abhinov Kasiviswanathan } 347ceed73a2SSubash Abhinov Kasiviswanathan 348ceed73a2SSubash Abhinov Kasiviswanathan /* Deaggregates a single packet 349ceed73a2SSubash Abhinov Kasiviswanathan * A whole new buffer is allocated for each portion of an aggregated frame. 350ceed73a2SSubash Abhinov Kasiviswanathan * Caller should keep calling deaggregate() on the source skb until 0 is 351ceed73a2SSubash Abhinov Kasiviswanathan * returned, indicating that there are no more packets to deaggregate. Caller 352ceed73a2SSubash Abhinov Kasiviswanathan * is responsible for freeing the original skb. 353ceed73a2SSubash Abhinov Kasiviswanathan */ 354bbd21b24SSubash Abhinov Kasiviswanathan struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb, 355bbd21b24SSubash Abhinov Kasiviswanathan struct rmnet_port *port) 356ceed73a2SSubash Abhinov Kasiviswanathan { 357e1d9a90aSSharath Chandra Vurukala struct rmnet_map_v5_csum_header *next_hdr = NULL; 358ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *maph; 359e1d9a90aSSharath Chandra Vurukala void *data = skb->data; 360ceed73a2SSubash Abhinov Kasiviswanathan struct sk_buff *skbn; 361e1d9a90aSSharath Chandra Vurukala u8 nexthdr_type; 362ceed73a2SSubash Abhinov Kasiviswanathan u32 packet_len; 363ceed73a2SSubash Abhinov Kasiviswanathan 364ceed73a2SSubash Abhinov Kasiviswanathan if (skb->len == 0) 365ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 366ceed73a2SSubash Abhinov Kasiviswanathan 367ceed73a2SSubash Abhinov Kasiviswanathan maph = (struct rmnet_map_header *)skb->data; 3689d131d04SAlex Elder packet_len = ntohs(maph->pkt_len) + sizeof(*maph); 369ceed73a2SSubash Abhinov Kasiviswanathan 370e1d9a90aSSharath Chandra Vurukala if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4) { 371bbd21b24SSubash Abhinov Kasiviswanathan packet_len += sizeof(struct rmnet_map_dl_csum_trailer); 372e1d9a90aSSharath Chandra Vurukala } else if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV5) { 373e1d9a90aSSharath Chandra Vurukala if (!(maph->flags & MAP_CMD_FLAG)) { 374e1d9a90aSSharath Chandra Vurukala packet_len += sizeof(*next_hdr); 375e1d9a90aSSharath Chandra Vurukala if (maph->flags & MAP_NEXT_HEADER_FLAG) 376e1d9a90aSSharath Chandra Vurukala next_hdr = data + sizeof(*maph); 377e1d9a90aSSharath Chandra Vurukala else 378e1d9a90aSSharath Chandra Vurukala /* Mapv5 data pkt without csum hdr is invalid */ 379e1d9a90aSSharath Chandra Vurukala return NULL; 380e1d9a90aSSharath Chandra Vurukala } 381e1d9a90aSSharath Chandra Vurukala } 382bbd21b24SSubash Abhinov Kasiviswanathan 383ceed73a2SSubash Abhinov Kasiviswanathan if (((int)skb->len - (int)packet_len) < 0) 384ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 385ceed73a2SSubash Abhinov Kasiviswanathan 3861f4f554aSDan Carpenter /* Some hardware can send us empty frames. Catch them */ 3879d131d04SAlex Elder if (!maph->pkt_len) 3881f4f554aSDan Carpenter return NULL; 3891f4f554aSDan Carpenter 390e1d9a90aSSharath Chandra Vurukala if (next_hdr) { 391e1d9a90aSSharath Chandra Vurukala nexthdr_type = u8_get_bits(next_hdr->header_info, 392e1d9a90aSSharath Chandra Vurukala MAPV5_HDRINFO_HDR_TYPE_FMASK); 393e1d9a90aSSharath Chandra Vurukala if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD) 394e1d9a90aSSharath Chandra Vurukala return NULL; 395e1d9a90aSSharath Chandra Vurukala } 396e1d9a90aSSharath Chandra Vurukala 397ceed73a2SSubash Abhinov Kasiviswanathan skbn = alloc_skb(packet_len + RMNET_MAP_DEAGGR_SPACING, GFP_ATOMIC); 398ceed73a2SSubash Abhinov Kasiviswanathan if (!skbn) 399ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 400ceed73a2SSubash Abhinov Kasiviswanathan 401ceed73a2SSubash Abhinov Kasiviswanathan skb_reserve(skbn, RMNET_MAP_DEAGGR_HEADROOM); 402ceed73a2SSubash Abhinov Kasiviswanathan skb_put(skbn, packet_len); 403ceed73a2SSubash Abhinov Kasiviswanathan memcpy(skbn->data, skb->data, packet_len); 404ceed73a2SSubash Abhinov Kasiviswanathan skb_pull(skb, packet_len); 405ceed73a2SSubash Abhinov Kasiviswanathan 406ceed73a2SSubash Abhinov Kasiviswanathan return skbn; 407ceed73a2SSubash Abhinov Kasiviswanathan } 408bbd21b24SSubash Abhinov Kasiviswanathan 409bbd21b24SSubash Abhinov Kasiviswanathan /* Validates packet checksums. Function takes a pointer to 410bbd21b24SSubash Abhinov Kasiviswanathan * the beginning of a buffer which contains the IP payload + 411bbd21b24SSubash Abhinov Kasiviswanathan * padding + checksum trailer. 412bbd21b24SSubash Abhinov Kasiviswanathan * Only IPv4 and IPv6 are supported along with TCP & UDP. 413bbd21b24SSubash Abhinov Kasiviswanathan * Fragmented or tunneled packets are not supported. 414bbd21b24SSubash Abhinov Kasiviswanathan */ 415bbd21b24SSubash Abhinov Kasiviswanathan int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len) 416bbd21b24SSubash Abhinov Kasiviswanathan { 417bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv = netdev_priv(skb->dev); 418bbd21b24SSubash Abhinov Kasiviswanathan struct rmnet_map_dl_csum_trailer *csum_trailer; 419bbd21b24SSubash Abhinov Kasiviswanathan 420bbde32d3SSubash Abhinov Kasiviswanathan if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) { 421bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_sw++; 422bbd21b24SSubash Abhinov Kasiviswanathan return -EOPNOTSUPP; 423bbde32d3SSubash Abhinov Kasiviswanathan } 424bbd21b24SSubash Abhinov Kasiviswanathan 425bbd21b24SSubash Abhinov Kasiviswanathan csum_trailer = (struct rmnet_map_dl_csum_trailer *)(skb->data + len); 426bbd21b24SSubash Abhinov Kasiviswanathan 427cc1b21baSAlex Elder if (!(csum_trailer->flags & MAP_CSUM_DL_VALID_FLAG)) { 428bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_valid_unset++; 429bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 430bbde32d3SSubash Abhinov Kasiviswanathan } 431bbd21b24SSubash Abhinov Kasiviswanathan 43275db5b07SAlex Elder if (skb->protocol == htons(ETH_P_IP)) 433bbde32d3SSubash Abhinov Kasiviswanathan return rmnet_map_ipv4_dl_csum_trailer(skb, csum_trailer, priv); 434bbd21b24SSubash Abhinov Kasiviswanathan 43575db5b07SAlex Elder if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) 43675db5b07SAlex Elder return rmnet_map_ipv6_dl_csum_trailer(skb, csum_trailer, priv); 43775db5b07SAlex Elder 43875db5b07SAlex Elder priv->stats.csum_err_invalid_ip_version++; 43975db5b07SAlex Elder 44075db5b07SAlex Elder return -EPROTONOSUPPORT; 441bbd21b24SSubash Abhinov Kasiviswanathan } 4425eb5f860SSubash Abhinov Kasiviswanathan 443b6e5d27eSSharath Chandra Vurukala static void rmnet_map_v4_checksum_uplink_packet(struct sk_buff *skb, 4445eb5f860SSubash Abhinov Kasiviswanathan struct net_device *orig_dev) 4455eb5f860SSubash Abhinov Kasiviswanathan { 446bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv = netdev_priv(orig_dev); 4475eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header; 4485eb5f860SSubash Abhinov Kasiviswanathan void *iphdr; 4495eb5f860SSubash Abhinov Kasiviswanathan 4505eb5f860SSubash Abhinov Kasiviswanathan ul_header = (struct rmnet_map_ul_csum_header *) 4515eb5f860SSubash Abhinov Kasiviswanathan skb_push(skb, sizeof(struct rmnet_map_ul_csum_header)); 4525eb5f860SSubash Abhinov Kasiviswanathan 4535eb5f860SSubash Abhinov Kasiviswanathan if (unlikely(!(orig_dev->features & 4545eb5f860SSubash Abhinov Kasiviswanathan (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)))) 4555eb5f860SSubash Abhinov Kasiviswanathan goto sw_csum; 4565eb5f860SSubash Abhinov Kasiviswanathan 45775db5b07SAlex Elder if (skb->ip_summed != CHECKSUM_PARTIAL) 45875db5b07SAlex Elder goto sw_csum; 45975db5b07SAlex Elder 4605eb5f860SSubash Abhinov Kasiviswanathan iphdr = (char *)ul_header + 4615eb5f860SSubash Abhinov Kasiviswanathan sizeof(struct rmnet_map_ul_csum_header); 4625eb5f860SSubash Abhinov Kasiviswanathan 4635eb5f860SSubash Abhinov Kasiviswanathan if (skb->protocol == htons(ETH_P_IP)) { 4645eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv4_ul_csum_header(iphdr, ul_header, skb); 465b6e5d27eSSharath Chandra Vurukala priv->stats.csum_hw++; 4665eb5f860SSubash Abhinov Kasiviswanathan return; 46775db5b07SAlex Elder } 46875db5b07SAlex Elder 46975db5b07SAlex Elder if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) { 4705eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv6_ul_csum_header(iphdr, ul_header, skb); 471b6e5d27eSSharath Chandra Vurukala priv->stats.csum_hw++; 4725eb5f860SSubash Abhinov Kasiviswanathan return; 4735eb5f860SSubash Abhinov Kasiviswanathan } 47475db5b07SAlex Elder 47575db5b07SAlex Elder priv->stats.csum_err_invalid_ip_version++; 4765eb5f860SSubash Abhinov Kasiviswanathan 4775eb5f860SSubash Abhinov Kasiviswanathan sw_csum: 47886ca860eSAlex Elder memset(ul_header, 0, sizeof(*ul_header)); 479bbde32d3SSubash Abhinov Kasiviswanathan 480bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_sw++; 4815eb5f860SSubash Abhinov Kasiviswanathan } 482e1d9a90aSSharath Chandra Vurukala 483b6e5d27eSSharath Chandra Vurukala /* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP 484b6e5d27eSSharath Chandra Vurukala * packets that are supported for UL checksum offload. 485b6e5d27eSSharath Chandra Vurukala */ 486b6e5d27eSSharath Chandra Vurukala void rmnet_map_checksum_uplink_packet(struct sk_buff *skb, 487b6e5d27eSSharath Chandra Vurukala struct rmnet_port *port, 488b6e5d27eSSharath Chandra Vurukala struct net_device *orig_dev, 489b6e5d27eSSharath Chandra Vurukala int csum_type) 490b6e5d27eSSharath Chandra Vurukala { 491b6e5d27eSSharath Chandra Vurukala switch (csum_type) { 492b6e5d27eSSharath Chandra Vurukala case RMNET_FLAGS_EGRESS_MAP_CKSUMV4: 493b6e5d27eSSharath Chandra Vurukala rmnet_map_v4_checksum_uplink_packet(skb, orig_dev); 494b6e5d27eSSharath Chandra Vurukala break; 495b6e5d27eSSharath Chandra Vurukala case RMNET_FLAGS_EGRESS_MAP_CKSUMV5: 496b6e5d27eSSharath Chandra Vurukala rmnet_map_v5_checksum_uplink_packet(skb, port, orig_dev); 497b6e5d27eSSharath Chandra Vurukala break; 498b6e5d27eSSharath Chandra Vurukala default: 499b6e5d27eSSharath Chandra Vurukala break; 500b6e5d27eSSharath Chandra Vurukala } 501b6e5d27eSSharath Chandra Vurukala } 502b6e5d27eSSharath Chandra Vurukala 503e1d9a90aSSharath Chandra Vurukala /* Process a MAPv5 packet header */ 504e1d9a90aSSharath Chandra Vurukala int rmnet_map_process_next_hdr_packet(struct sk_buff *skb, 505e1d9a90aSSharath Chandra Vurukala u16 len) 506e1d9a90aSSharath Chandra Vurukala { 507e1d9a90aSSharath Chandra Vurukala struct rmnet_priv *priv = netdev_priv(skb->dev); 508e1d9a90aSSharath Chandra Vurukala struct rmnet_map_v5_csum_header *next_hdr; 509e1d9a90aSSharath Chandra Vurukala u8 nexthdr_type; 510e1d9a90aSSharath Chandra Vurukala 511e1d9a90aSSharath Chandra Vurukala next_hdr = (struct rmnet_map_v5_csum_header *)(skb->data + 512e1d9a90aSSharath Chandra Vurukala sizeof(struct rmnet_map_header)); 513e1d9a90aSSharath Chandra Vurukala 514e1d9a90aSSharath Chandra Vurukala nexthdr_type = u8_get_bits(next_hdr->header_info, 515e1d9a90aSSharath Chandra Vurukala MAPV5_HDRINFO_HDR_TYPE_FMASK); 516e1d9a90aSSharath Chandra Vurukala 517e1d9a90aSSharath Chandra Vurukala if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD) 518e1d9a90aSSharath Chandra Vurukala return -EINVAL; 519e1d9a90aSSharath Chandra Vurukala 520e1d9a90aSSharath Chandra Vurukala if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) { 521e1d9a90aSSharath Chandra Vurukala priv->stats.csum_sw++; 522e1d9a90aSSharath Chandra Vurukala } else if (next_hdr->csum_info & MAPV5_CSUMINFO_VALID_FLAG) { 523e1d9a90aSSharath Chandra Vurukala priv->stats.csum_ok++; 524e1d9a90aSSharath Chandra Vurukala skb->ip_summed = CHECKSUM_UNNECESSARY; 525e1d9a90aSSharath Chandra Vurukala } else { 526e1d9a90aSSharath Chandra Vurukala priv->stats.csum_valid_unset++; 527e1d9a90aSSharath Chandra Vurukala } 528e1d9a90aSSharath Chandra Vurukala 529e1d9a90aSSharath Chandra Vurukala /* Pull csum v5 header */ 530e1d9a90aSSharath Chandra Vurukala skb_pull(skb, sizeof(*next_hdr)); 531e1d9a90aSSharath Chandra Vurukala 532e1d9a90aSSharath Chandra Vurukala return 0; 533e1d9a90aSSharath Chandra Vurukala } 534