197fb5e8dSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 29dcaec04SSubash Abhinov Kasiviswanathan /* Copyright (c) 2013-2018, 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> 11ceed73a2SSubash Abhinov Kasiviswanathan #include "rmnet_config.h" 12ceed73a2SSubash Abhinov Kasiviswanathan #include "rmnet_map.h" 13ceed73a2SSubash Abhinov Kasiviswanathan #include "rmnet_private.h" 14ceed73a2SSubash Abhinov Kasiviswanathan 15ceed73a2SSubash Abhinov Kasiviswanathan #define RMNET_MAP_DEAGGR_SPACING 64 16ceed73a2SSubash Abhinov Kasiviswanathan #define RMNET_MAP_DEAGGR_HEADROOM (RMNET_MAP_DEAGGR_SPACING / 2) 17ceed73a2SSubash Abhinov Kasiviswanathan 18bbd21b24SSubash Abhinov Kasiviswanathan static __sum16 *rmnet_map_get_csum_field(unsigned char protocol, 19bbd21b24SSubash Abhinov Kasiviswanathan const void *txporthdr) 20bbd21b24SSubash Abhinov Kasiviswanathan { 21bbd21b24SSubash Abhinov Kasiviswanathan __sum16 *check = NULL; 22bbd21b24SSubash Abhinov Kasiviswanathan 23bbd21b24SSubash Abhinov Kasiviswanathan switch (protocol) { 24bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_TCP: 25bbd21b24SSubash Abhinov Kasiviswanathan check = &(((struct tcphdr *)txporthdr)->check); 26bbd21b24SSubash Abhinov Kasiviswanathan break; 27bbd21b24SSubash Abhinov Kasiviswanathan 28bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_UDP: 29bbd21b24SSubash Abhinov Kasiviswanathan check = &(((struct udphdr *)txporthdr)->check); 30bbd21b24SSubash Abhinov Kasiviswanathan break; 31bbd21b24SSubash Abhinov Kasiviswanathan 32bbd21b24SSubash Abhinov Kasiviswanathan default: 33bbd21b24SSubash Abhinov Kasiviswanathan check = NULL; 34bbd21b24SSubash Abhinov Kasiviswanathan break; 35bbd21b24SSubash Abhinov Kasiviswanathan } 36bbd21b24SSubash Abhinov Kasiviswanathan 37bbd21b24SSubash Abhinov Kasiviswanathan return check; 38bbd21b24SSubash Abhinov Kasiviswanathan } 39bbd21b24SSubash Abhinov Kasiviswanathan 40bbd21b24SSubash Abhinov Kasiviswanathan static int 41bbd21b24SSubash Abhinov Kasiviswanathan rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb, 42bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_map_dl_csum_trailer *csum_trailer, 43bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv) 44bbd21b24SSubash Abhinov Kasiviswanathan { 45bbd21b24SSubash Abhinov Kasiviswanathan __sum16 *csum_field, csum_temp, pseudo_csum, hdr_csum, ip_payload_csum; 46bbd21b24SSubash Abhinov Kasiviswanathan u16 csum_value, csum_value_final; 47bbd21b24SSubash Abhinov Kasiviswanathan struct iphdr *ip4h; 48bbd21b24SSubash Abhinov Kasiviswanathan void *txporthdr; 49bbd21b24SSubash Abhinov Kasiviswanathan __be16 addend; 50bbd21b24SSubash Abhinov Kasiviswanathan 51bbd21b24SSubash Abhinov Kasiviswanathan ip4h = (struct iphdr *)(skb->data); 52bbd21b24SSubash Abhinov Kasiviswanathan if ((ntohs(ip4h->frag_off) & IP_MF) || 53bbde32d3SSubash Abhinov Kasiviswanathan ((ntohs(ip4h->frag_off) & IP_OFFSET) > 0)) { 54bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_fragmented_pkt++; 55bbd21b24SSubash Abhinov Kasiviswanathan return -EOPNOTSUPP; 56bbde32d3SSubash Abhinov Kasiviswanathan } 57bbd21b24SSubash Abhinov Kasiviswanathan 58bbd21b24SSubash Abhinov Kasiviswanathan txporthdr = skb->data + ip4h->ihl * 4; 59bbd21b24SSubash Abhinov Kasiviswanathan 60bbd21b24SSubash Abhinov Kasiviswanathan csum_field = rmnet_map_get_csum_field(ip4h->protocol, txporthdr); 61bbd21b24SSubash Abhinov Kasiviswanathan 62bbde32d3SSubash Abhinov Kasiviswanathan if (!csum_field) { 63bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_transport++; 64bbd21b24SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 65bbde32d3SSubash Abhinov Kasiviswanathan } 66bbd21b24SSubash Abhinov Kasiviswanathan 67bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 768 - Skip IPv4 UDP packets where sender checksum field is 0 */ 68bbde32d3SSubash Abhinov Kasiviswanathan if (*csum_field == 0 && ip4h->protocol == IPPROTO_UDP) { 69bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_skipped++; 70bbd21b24SSubash Abhinov Kasiviswanathan return 0; 71bbde32d3SSubash Abhinov Kasiviswanathan } 72bbd21b24SSubash Abhinov Kasiviswanathan 73bbd21b24SSubash Abhinov Kasiviswanathan csum_value = ~ntohs(csum_trailer->csum_value); 74bbd21b24SSubash Abhinov Kasiviswanathan hdr_csum = ~ip_fast_csum(ip4h, (int)ip4h->ihl); 75bbd21b24SSubash Abhinov Kasiviswanathan ip_payload_csum = csum16_sub((__force __sum16)csum_value, 76bbd21b24SSubash Abhinov Kasiviswanathan (__force __be16)hdr_csum); 77bbd21b24SSubash Abhinov Kasiviswanathan 78bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = ~csum_tcpudp_magic(ip4h->saddr, ip4h->daddr, 79bbd21b24SSubash Abhinov Kasiviswanathan ntohs(ip4h->tot_len) - ip4h->ihl * 4, 80bbd21b24SSubash Abhinov Kasiviswanathan ip4h->protocol, 0); 81bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)pseudo_csum); 82bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = csum16_add(ip_payload_csum, addend); 83bbd21b24SSubash Abhinov Kasiviswanathan 84bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)*csum_field); 85bbd21b24SSubash Abhinov Kasiviswanathan csum_temp = ~csum16_sub(pseudo_csum, addend); 86bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = (__force u16)csum_temp; 87bbd21b24SSubash Abhinov Kasiviswanathan 88bbd21b24SSubash Abhinov Kasiviswanathan if (unlikely(csum_value_final == 0)) { 89bbd21b24SSubash Abhinov Kasiviswanathan switch (ip4h->protocol) { 90bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_UDP: 91bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 768 - DL4 1's complement rule for UDP csum 0 */ 92bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 93bbd21b24SSubash Abhinov Kasiviswanathan break; 94bbd21b24SSubash Abhinov Kasiviswanathan 95bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_TCP: 96bbd21b24SSubash Abhinov Kasiviswanathan /* DL4 Non-RFC compliant TCP checksum found */ 97bbd21b24SSubash Abhinov Kasiviswanathan if (*csum_field == (__force __sum16)0xFFFF) 98bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 99bbd21b24SSubash Abhinov Kasiviswanathan break; 100bbd21b24SSubash Abhinov Kasiviswanathan } 101bbd21b24SSubash Abhinov Kasiviswanathan } 102bbd21b24SSubash Abhinov Kasiviswanathan 103bbde32d3SSubash Abhinov Kasiviswanathan if (csum_value_final == ntohs((__force __be16)*csum_field)) { 104bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_ok++; 105bbd21b24SSubash Abhinov Kasiviswanathan return 0; 106bbde32d3SSubash Abhinov Kasiviswanathan } else { 107bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_validation_failed++; 108bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 109bbd21b24SSubash Abhinov Kasiviswanathan } 110bbde32d3SSubash Abhinov Kasiviswanathan } 111bbd21b24SSubash Abhinov Kasiviswanathan 112bbd21b24SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 113bbd21b24SSubash Abhinov Kasiviswanathan static int 114bbd21b24SSubash Abhinov Kasiviswanathan rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, 115bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_map_dl_csum_trailer *csum_trailer, 116bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv) 117bbd21b24SSubash Abhinov Kasiviswanathan { 118bbd21b24SSubash Abhinov Kasiviswanathan __sum16 *csum_field, ip6_payload_csum, pseudo_csum, csum_temp; 119bbd21b24SSubash Abhinov Kasiviswanathan u16 csum_value, csum_value_final; 120bbd21b24SSubash Abhinov Kasiviswanathan __be16 ip6_hdr_csum, addend; 121bbd21b24SSubash Abhinov Kasiviswanathan struct ipv6hdr *ip6h; 122bbd21b24SSubash Abhinov Kasiviswanathan void *txporthdr; 123bbd21b24SSubash Abhinov Kasiviswanathan u32 length; 124bbd21b24SSubash Abhinov Kasiviswanathan 125bbd21b24SSubash Abhinov Kasiviswanathan ip6h = (struct ipv6hdr *)(skb->data); 126bbd21b24SSubash Abhinov Kasiviswanathan 127bbd21b24SSubash Abhinov Kasiviswanathan txporthdr = skb->data + sizeof(struct ipv6hdr); 128bbd21b24SSubash Abhinov Kasiviswanathan csum_field = rmnet_map_get_csum_field(ip6h->nexthdr, txporthdr); 129bbd21b24SSubash Abhinov Kasiviswanathan 130bbde32d3SSubash Abhinov Kasiviswanathan if (!csum_field) { 131bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_transport++; 132bbd21b24SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 133bbde32d3SSubash Abhinov Kasiviswanathan } 134bbd21b24SSubash Abhinov Kasiviswanathan 135bbd21b24SSubash Abhinov Kasiviswanathan csum_value = ~ntohs(csum_trailer->csum_value); 136bbd21b24SSubash Abhinov Kasiviswanathan ip6_hdr_csum = (__force __be16) 137bbd21b24SSubash Abhinov Kasiviswanathan ~ntohs((__force __be16)ip_compute_csum(ip6h, 138bbd21b24SSubash Abhinov Kasiviswanathan (int)(txporthdr - (void *)(skb->data)))); 139bbd21b24SSubash Abhinov Kasiviswanathan ip6_payload_csum = csum16_sub((__force __sum16)csum_value, 140bbd21b24SSubash Abhinov Kasiviswanathan ip6_hdr_csum); 141bbd21b24SSubash Abhinov Kasiviswanathan 142bbd21b24SSubash Abhinov Kasiviswanathan length = (ip6h->nexthdr == IPPROTO_UDP) ? 143bbd21b24SSubash Abhinov Kasiviswanathan ntohs(((struct udphdr *)txporthdr)->len) : 144bbd21b24SSubash Abhinov Kasiviswanathan ntohs(ip6h->payload_len); 145bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = ~(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, 146bbd21b24SSubash Abhinov Kasiviswanathan length, ip6h->nexthdr, 0)); 147bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)pseudo_csum); 148bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = csum16_add(ip6_payload_csum, addend); 149bbd21b24SSubash Abhinov Kasiviswanathan 150bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)*csum_field); 151bbd21b24SSubash Abhinov Kasiviswanathan csum_temp = ~csum16_sub(pseudo_csum, addend); 152bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = (__force u16)csum_temp; 153bbd21b24SSubash Abhinov Kasiviswanathan 154bbd21b24SSubash Abhinov Kasiviswanathan if (unlikely(csum_value_final == 0)) { 155bbd21b24SSubash Abhinov Kasiviswanathan switch (ip6h->nexthdr) { 156bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_UDP: 157bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 2460 section 8.1 158bbd21b24SSubash Abhinov Kasiviswanathan * DL6 One's complement rule for UDP checksum 0 159bbd21b24SSubash Abhinov Kasiviswanathan */ 160bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 161bbd21b24SSubash Abhinov Kasiviswanathan break; 162bbd21b24SSubash Abhinov Kasiviswanathan 163bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_TCP: 164bbd21b24SSubash Abhinov Kasiviswanathan /* DL6 Non-RFC compliant TCP checksum found */ 165bbd21b24SSubash Abhinov Kasiviswanathan if (*csum_field == (__force __sum16)0xFFFF) 166bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 167bbd21b24SSubash Abhinov Kasiviswanathan break; 168bbd21b24SSubash Abhinov Kasiviswanathan } 169bbd21b24SSubash Abhinov Kasiviswanathan } 170bbd21b24SSubash Abhinov Kasiviswanathan 171bbde32d3SSubash Abhinov Kasiviswanathan if (csum_value_final == ntohs((__force __be16)*csum_field)) { 172bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_ok++; 173bbd21b24SSubash Abhinov Kasiviswanathan return 0; 174bbde32d3SSubash Abhinov Kasiviswanathan } else { 175bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_validation_failed++; 176bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 177bbd21b24SSubash Abhinov Kasiviswanathan } 178bbde32d3SSubash Abhinov Kasiviswanathan } 179bbd21b24SSubash Abhinov Kasiviswanathan #endif 180bbd21b24SSubash Abhinov Kasiviswanathan 1815eb5f860SSubash Abhinov Kasiviswanathan static void rmnet_map_complement_ipv4_txporthdr_csum_field(void *iphdr) 1825eb5f860SSubash Abhinov Kasiviswanathan { 1835eb5f860SSubash Abhinov Kasiviswanathan struct iphdr *ip4h = (struct iphdr *)iphdr; 1845eb5f860SSubash Abhinov Kasiviswanathan void *txphdr; 1855eb5f860SSubash Abhinov Kasiviswanathan u16 *csum; 1865eb5f860SSubash Abhinov Kasiviswanathan 1875eb5f860SSubash Abhinov Kasiviswanathan txphdr = iphdr + ip4h->ihl * 4; 1885eb5f860SSubash Abhinov Kasiviswanathan 1895eb5f860SSubash Abhinov Kasiviswanathan if (ip4h->protocol == IPPROTO_TCP || ip4h->protocol == IPPROTO_UDP) { 1905eb5f860SSubash Abhinov Kasiviswanathan csum = (u16 *)rmnet_map_get_csum_field(ip4h->protocol, txphdr); 1915eb5f860SSubash Abhinov Kasiviswanathan *csum = ~(*csum); 1925eb5f860SSubash Abhinov Kasiviswanathan } 1935eb5f860SSubash Abhinov Kasiviswanathan } 1945eb5f860SSubash Abhinov Kasiviswanathan 1955eb5f860SSubash Abhinov Kasiviswanathan static void 1965eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv4_ul_csum_header(void *iphdr, 1975eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header, 1985eb5f860SSubash Abhinov Kasiviswanathan struct sk_buff *skb) 1995eb5f860SSubash Abhinov Kasiviswanathan { 20050c62a11SAlex Elder __be16 *hdr = (__be16 *)ul_header; 20150c62a11SAlex Elder struct iphdr *ip4h = iphdr; 2025eb5f860SSubash Abhinov Kasiviswanathan 20350c62a11SAlex Elder ul_header->csum_start_offset = htons(skb_network_header_len(skb)); 2045eb5f860SSubash Abhinov Kasiviswanathan ul_header->csum_insert_offset = skb->csum_offset; 2055eb5f860SSubash Abhinov Kasiviswanathan ul_header->csum_enabled = 1; 2065eb5f860SSubash Abhinov Kasiviswanathan if (ip4h->protocol == IPPROTO_UDP) 207a7cf3d24SSubash Abhinov Kasiviswanathan ul_header->udp_ind = 1; 2085eb5f860SSubash Abhinov Kasiviswanathan else 209a7cf3d24SSubash Abhinov Kasiviswanathan ul_header->udp_ind = 0; 2105eb5f860SSubash Abhinov Kasiviswanathan 2115eb5f860SSubash Abhinov Kasiviswanathan /* Changing remaining fields to network order */ 2125eb5f860SSubash Abhinov Kasiviswanathan hdr++; 2135eb5f860SSubash Abhinov Kasiviswanathan *hdr = htons((__force u16)*hdr); 2145eb5f860SSubash Abhinov Kasiviswanathan 2155eb5f860SSubash Abhinov Kasiviswanathan skb->ip_summed = CHECKSUM_NONE; 2165eb5f860SSubash Abhinov Kasiviswanathan 2175eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_complement_ipv4_txporthdr_csum_field(iphdr); 2185eb5f860SSubash Abhinov Kasiviswanathan } 2195eb5f860SSubash Abhinov Kasiviswanathan 2205eb5f860SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 2215eb5f860SSubash Abhinov Kasiviswanathan static void rmnet_map_complement_ipv6_txporthdr_csum_field(void *ip6hdr) 2225eb5f860SSubash Abhinov Kasiviswanathan { 2235eb5f860SSubash Abhinov Kasiviswanathan struct ipv6hdr *ip6h = (struct ipv6hdr *)ip6hdr; 2245eb5f860SSubash Abhinov Kasiviswanathan void *txphdr; 2255eb5f860SSubash Abhinov Kasiviswanathan u16 *csum; 2265eb5f860SSubash Abhinov Kasiviswanathan 2275eb5f860SSubash Abhinov Kasiviswanathan txphdr = ip6hdr + sizeof(struct ipv6hdr); 2285eb5f860SSubash Abhinov Kasiviswanathan 2295eb5f860SSubash Abhinov Kasiviswanathan if (ip6h->nexthdr == IPPROTO_TCP || ip6h->nexthdr == IPPROTO_UDP) { 2305eb5f860SSubash Abhinov Kasiviswanathan csum = (u16 *)rmnet_map_get_csum_field(ip6h->nexthdr, txphdr); 2315eb5f860SSubash Abhinov Kasiviswanathan *csum = ~(*csum); 2325eb5f860SSubash Abhinov Kasiviswanathan } 2335eb5f860SSubash Abhinov Kasiviswanathan } 2345eb5f860SSubash Abhinov Kasiviswanathan 2355eb5f860SSubash Abhinov Kasiviswanathan static void 2365eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv6_ul_csum_header(void *ip6hdr, 2375eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header, 2385eb5f860SSubash Abhinov Kasiviswanathan struct sk_buff *skb) 2395eb5f860SSubash Abhinov Kasiviswanathan { 24050c62a11SAlex Elder __be16 *hdr = (__be16 *)ul_header; 24150c62a11SAlex Elder struct ipv6hdr *ip6h = ip6hdr; 2425eb5f860SSubash Abhinov Kasiviswanathan 24350c62a11SAlex Elder ul_header->csum_start_offset = htons(skb_network_header_len(skb)); 2445eb5f860SSubash Abhinov Kasiviswanathan ul_header->csum_insert_offset = skb->csum_offset; 2455eb5f860SSubash Abhinov Kasiviswanathan ul_header->csum_enabled = 1; 246a7cf3d24SSubash Abhinov Kasiviswanathan 247a7cf3d24SSubash Abhinov Kasiviswanathan if (ip6h->nexthdr == IPPROTO_UDP) 248a7cf3d24SSubash Abhinov Kasiviswanathan ul_header->udp_ind = 1; 249a7cf3d24SSubash Abhinov Kasiviswanathan else 250a7cf3d24SSubash Abhinov Kasiviswanathan ul_header->udp_ind = 0; 2515eb5f860SSubash Abhinov Kasiviswanathan 2525eb5f860SSubash Abhinov Kasiviswanathan /* Changing remaining fields to network order */ 2535eb5f860SSubash Abhinov Kasiviswanathan hdr++; 2545eb5f860SSubash Abhinov Kasiviswanathan *hdr = htons((__force u16)*hdr); 2555eb5f860SSubash Abhinov Kasiviswanathan 2565eb5f860SSubash Abhinov Kasiviswanathan skb->ip_summed = CHECKSUM_NONE; 2575eb5f860SSubash Abhinov Kasiviswanathan 2585eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_complement_ipv6_txporthdr_csum_field(ip6hdr); 2595eb5f860SSubash Abhinov Kasiviswanathan } 2605eb5f860SSubash Abhinov Kasiviswanathan #endif 2615eb5f860SSubash Abhinov Kasiviswanathan 262ceed73a2SSubash Abhinov Kasiviswanathan /* Adds MAP header to front of skb->data 263ceed73a2SSubash Abhinov Kasiviswanathan * Padding is calculated and set appropriately in MAP header. Mux ID is 264ceed73a2SSubash Abhinov Kasiviswanathan * initialized to 0. 265ceed73a2SSubash Abhinov Kasiviswanathan */ 266ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb, 267ceed73a2SSubash Abhinov Kasiviswanathan int hdrlen, int pad) 268ceed73a2SSubash Abhinov Kasiviswanathan { 269ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *map_header; 270ceed73a2SSubash Abhinov Kasiviswanathan u32 padding, map_datalen; 271ceed73a2SSubash Abhinov Kasiviswanathan u8 *padbytes; 272ceed73a2SSubash Abhinov Kasiviswanathan 273ceed73a2SSubash Abhinov Kasiviswanathan map_datalen = skb->len - hdrlen; 274ceed73a2SSubash Abhinov Kasiviswanathan map_header = (struct rmnet_map_header *) 275ceed73a2SSubash Abhinov Kasiviswanathan skb_push(skb, sizeof(struct rmnet_map_header)); 276ceed73a2SSubash Abhinov Kasiviswanathan memset(map_header, 0, sizeof(struct rmnet_map_header)); 277ceed73a2SSubash Abhinov Kasiviswanathan 278ceed73a2SSubash Abhinov Kasiviswanathan if (pad == RMNET_MAP_NO_PAD_BYTES) { 279ceed73a2SSubash Abhinov Kasiviswanathan map_header->pkt_len = htons(map_datalen); 280ceed73a2SSubash Abhinov Kasiviswanathan return map_header; 281ceed73a2SSubash Abhinov Kasiviswanathan } 282ceed73a2SSubash Abhinov Kasiviswanathan 28316653c16SAlex Elder BUILD_BUG_ON(MAP_PAD_LEN_MASK < 3); 284ceed73a2SSubash Abhinov Kasiviswanathan padding = ALIGN(map_datalen, 4) - map_datalen; 285ceed73a2SSubash Abhinov Kasiviswanathan 286ceed73a2SSubash Abhinov Kasiviswanathan if (padding == 0) 287ceed73a2SSubash Abhinov Kasiviswanathan goto done; 288ceed73a2SSubash Abhinov Kasiviswanathan 289ceed73a2SSubash Abhinov Kasiviswanathan if (skb_tailroom(skb) < padding) 290ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 291ceed73a2SSubash Abhinov Kasiviswanathan 292ceed73a2SSubash Abhinov Kasiviswanathan padbytes = (u8 *)skb_put(skb, padding); 293ceed73a2SSubash Abhinov Kasiviswanathan memset(padbytes, 0, padding); 294ceed73a2SSubash Abhinov Kasiviswanathan 295ceed73a2SSubash Abhinov Kasiviswanathan done: 296ceed73a2SSubash Abhinov Kasiviswanathan map_header->pkt_len = htons(map_datalen + padding); 29716653c16SAlex Elder /* This is a data packet, so the CMD bit is 0 */ 29816653c16SAlex Elder map_header->flags = padding & MAP_PAD_LEN_MASK; 299ceed73a2SSubash Abhinov Kasiviswanathan 300ceed73a2SSubash Abhinov Kasiviswanathan return map_header; 301ceed73a2SSubash Abhinov Kasiviswanathan } 302ceed73a2SSubash Abhinov Kasiviswanathan 303ceed73a2SSubash Abhinov Kasiviswanathan /* Deaggregates a single packet 304ceed73a2SSubash Abhinov Kasiviswanathan * A whole new buffer is allocated for each portion of an aggregated frame. 305ceed73a2SSubash Abhinov Kasiviswanathan * Caller should keep calling deaggregate() on the source skb until 0 is 306ceed73a2SSubash Abhinov Kasiviswanathan * returned, indicating that there are no more packets to deaggregate. Caller 307ceed73a2SSubash Abhinov Kasiviswanathan * is responsible for freeing the original skb. 308ceed73a2SSubash Abhinov Kasiviswanathan */ 309bbd21b24SSubash Abhinov Kasiviswanathan struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb, 310bbd21b24SSubash Abhinov Kasiviswanathan struct rmnet_port *port) 311ceed73a2SSubash Abhinov Kasiviswanathan { 312ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *maph; 313ceed73a2SSubash Abhinov Kasiviswanathan struct sk_buff *skbn; 314ceed73a2SSubash Abhinov Kasiviswanathan u32 packet_len; 315ceed73a2SSubash Abhinov Kasiviswanathan 316ceed73a2SSubash Abhinov Kasiviswanathan if (skb->len == 0) 317ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 318ceed73a2SSubash Abhinov Kasiviswanathan 319ceed73a2SSubash Abhinov Kasiviswanathan maph = (struct rmnet_map_header *)skb->data; 3209d131d04SAlex Elder packet_len = ntohs(maph->pkt_len) + sizeof(*maph); 321ceed73a2SSubash Abhinov Kasiviswanathan 32214452ca3SSubash Abhinov Kasiviswanathan if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4) 323bbd21b24SSubash Abhinov Kasiviswanathan packet_len += sizeof(struct rmnet_map_dl_csum_trailer); 324bbd21b24SSubash Abhinov Kasiviswanathan 325ceed73a2SSubash Abhinov Kasiviswanathan if (((int)skb->len - (int)packet_len) < 0) 326ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 327ceed73a2SSubash Abhinov Kasiviswanathan 3281f4f554aSDan Carpenter /* Some hardware can send us empty frames. Catch them */ 3299d131d04SAlex Elder if (!maph->pkt_len) 3301f4f554aSDan Carpenter return NULL; 3311f4f554aSDan Carpenter 332ceed73a2SSubash Abhinov Kasiviswanathan skbn = alloc_skb(packet_len + RMNET_MAP_DEAGGR_SPACING, GFP_ATOMIC); 333ceed73a2SSubash Abhinov Kasiviswanathan if (!skbn) 334ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 335ceed73a2SSubash Abhinov Kasiviswanathan 336ceed73a2SSubash Abhinov Kasiviswanathan skb_reserve(skbn, RMNET_MAP_DEAGGR_HEADROOM); 337ceed73a2SSubash Abhinov Kasiviswanathan skb_put(skbn, packet_len); 338ceed73a2SSubash Abhinov Kasiviswanathan memcpy(skbn->data, skb->data, packet_len); 339ceed73a2SSubash Abhinov Kasiviswanathan skb_pull(skb, packet_len); 340ceed73a2SSubash Abhinov Kasiviswanathan 341ceed73a2SSubash Abhinov Kasiviswanathan return skbn; 342ceed73a2SSubash Abhinov Kasiviswanathan } 343bbd21b24SSubash Abhinov Kasiviswanathan 344bbd21b24SSubash Abhinov Kasiviswanathan /* Validates packet checksums. Function takes a pointer to 345bbd21b24SSubash Abhinov Kasiviswanathan * the beginning of a buffer which contains the IP payload + 346bbd21b24SSubash Abhinov Kasiviswanathan * padding + checksum trailer. 347bbd21b24SSubash Abhinov Kasiviswanathan * Only IPv4 and IPv6 are supported along with TCP & UDP. 348bbd21b24SSubash Abhinov Kasiviswanathan * Fragmented or tunneled packets are not supported. 349bbd21b24SSubash Abhinov Kasiviswanathan */ 350bbd21b24SSubash Abhinov Kasiviswanathan int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len) 351bbd21b24SSubash Abhinov Kasiviswanathan { 352bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv = netdev_priv(skb->dev); 353bbd21b24SSubash Abhinov Kasiviswanathan struct rmnet_map_dl_csum_trailer *csum_trailer; 354bbd21b24SSubash Abhinov Kasiviswanathan 355bbde32d3SSubash Abhinov Kasiviswanathan if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) { 356bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_sw++; 357bbd21b24SSubash Abhinov Kasiviswanathan return -EOPNOTSUPP; 358bbde32d3SSubash Abhinov Kasiviswanathan } 359bbd21b24SSubash Abhinov Kasiviswanathan 360bbd21b24SSubash Abhinov Kasiviswanathan csum_trailer = (struct rmnet_map_dl_csum_trailer *)(skb->data + len); 361bbd21b24SSubash Abhinov Kasiviswanathan 362*cc1b21baSAlex Elder if (!(csum_trailer->flags & MAP_CSUM_DL_VALID_FLAG)) { 363bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_valid_unset++; 364bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 365bbde32d3SSubash Abhinov Kasiviswanathan } 366bbd21b24SSubash Abhinov Kasiviswanathan 367bbde32d3SSubash Abhinov Kasiviswanathan if (skb->protocol == htons(ETH_P_IP)) { 368bbde32d3SSubash Abhinov Kasiviswanathan return rmnet_map_ipv4_dl_csum_trailer(skb, csum_trailer, priv); 369bbde32d3SSubash Abhinov Kasiviswanathan } else if (skb->protocol == htons(ETH_P_IPV6)) { 370bbd21b24SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 371bbde32d3SSubash Abhinov Kasiviswanathan return rmnet_map_ipv6_dl_csum_trailer(skb, csum_trailer, priv); 372bbd21b24SSubash Abhinov Kasiviswanathan #else 373bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_ip_version++; 374bbd21b24SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 375bbd21b24SSubash Abhinov Kasiviswanathan #endif 376bbde32d3SSubash Abhinov Kasiviswanathan } else { 377bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_ip_version++; 378bbde32d3SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 379bbde32d3SSubash Abhinov Kasiviswanathan } 380bbd21b24SSubash Abhinov Kasiviswanathan 381bbd21b24SSubash Abhinov Kasiviswanathan return 0; 382bbd21b24SSubash Abhinov Kasiviswanathan } 3835eb5f860SSubash Abhinov Kasiviswanathan 3845eb5f860SSubash Abhinov Kasiviswanathan /* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP 3855eb5f860SSubash Abhinov Kasiviswanathan * packets that are supported for UL checksum offload. 3865eb5f860SSubash Abhinov Kasiviswanathan */ 3875eb5f860SSubash Abhinov Kasiviswanathan void rmnet_map_checksum_uplink_packet(struct sk_buff *skb, 3885eb5f860SSubash Abhinov Kasiviswanathan struct net_device *orig_dev) 3895eb5f860SSubash Abhinov Kasiviswanathan { 390bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv = netdev_priv(orig_dev); 3915eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header; 3925eb5f860SSubash Abhinov Kasiviswanathan void *iphdr; 3935eb5f860SSubash Abhinov Kasiviswanathan 3945eb5f860SSubash Abhinov Kasiviswanathan ul_header = (struct rmnet_map_ul_csum_header *) 3955eb5f860SSubash Abhinov Kasiviswanathan skb_push(skb, sizeof(struct rmnet_map_ul_csum_header)); 3965eb5f860SSubash Abhinov Kasiviswanathan 3975eb5f860SSubash Abhinov Kasiviswanathan if (unlikely(!(orig_dev->features & 3985eb5f860SSubash Abhinov Kasiviswanathan (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)))) 3995eb5f860SSubash Abhinov Kasiviswanathan goto sw_csum; 4005eb5f860SSubash Abhinov Kasiviswanathan 4015eb5f860SSubash Abhinov Kasiviswanathan if (skb->ip_summed == CHECKSUM_PARTIAL) { 4025eb5f860SSubash Abhinov Kasiviswanathan iphdr = (char *)ul_header + 4035eb5f860SSubash Abhinov Kasiviswanathan sizeof(struct rmnet_map_ul_csum_header); 4045eb5f860SSubash Abhinov Kasiviswanathan 4055eb5f860SSubash Abhinov Kasiviswanathan if (skb->protocol == htons(ETH_P_IP)) { 4065eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv4_ul_csum_header(iphdr, ul_header, skb); 4075eb5f860SSubash Abhinov Kasiviswanathan return; 4085eb5f860SSubash Abhinov Kasiviswanathan } else if (skb->protocol == htons(ETH_P_IPV6)) { 4095eb5f860SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 4105eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv6_ul_csum_header(iphdr, ul_header, skb); 4115eb5f860SSubash Abhinov Kasiviswanathan return; 4125eb5f860SSubash Abhinov Kasiviswanathan #else 413bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_ip_version++; 4145eb5f860SSubash Abhinov Kasiviswanathan goto sw_csum; 4155eb5f860SSubash Abhinov Kasiviswanathan #endif 416bbde32d3SSubash Abhinov Kasiviswanathan } else { 417bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_ip_version++; 4185eb5f860SSubash Abhinov Kasiviswanathan } 4195eb5f860SSubash Abhinov Kasiviswanathan } 4205eb5f860SSubash Abhinov Kasiviswanathan 4215eb5f860SSubash Abhinov Kasiviswanathan sw_csum: 4225eb5f860SSubash Abhinov Kasiviswanathan ul_header->csum_start_offset = 0; 4235eb5f860SSubash Abhinov Kasiviswanathan ul_header->csum_insert_offset = 0; 4245eb5f860SSubash Abhinov Kasiviswanathan ul_header->csum_enabled = 0; 425a7cf3d24SSubash Abhinov Kasiviswanathan ul_header->udp_ind = 0; 426bbde32d3SSubash Abhinov Kasiviswanathan 427bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_sw++; 4285eb5f860SSubash Abhinov Kasiviswanathan } 429