197fb5e8dSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 2*e1d9a90aSSharath 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> 11*e1d9a90aSSharath 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); 53bbd21b24SSubash Abhinov Kasiviswanathan if ((ntohs(ip4h->frag_off) & IP_MF) || 54bbde32d3SSubash Abhinov Kasiviswanathan ((ntohs(ip4h->frag_off) & IP_OFFSET) > 0)) { 55bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_fragmented_pkt++; 56bbd21b24SSubash Abhinov Kasiviswanathan return -EOPNOTSUPP; 57bbde32d3SSubash Abhinov Kasiviswanathan } 58bbd21b24SSubash Abhinov Kasiviswanathan 59bbd21b24SSubash Abhinov Kasiviswanathan txporthdr = skb->data + ip4h->ihl * 4; 60bbd21b24SSubash Abhinov Kasiviswanathan 61bbd21b24SSubash Abhinov Kasiviswanathan csum_field = rmnet_map_get_csum_field(ip4h->protocol, txporthdr); 62bbd21b24SSubash Abhinov Kasiviswanathan 63bbde32d3SSubash Abhinov Kasiviswanathan if (!csum_field) { 64bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_transport++; 65bbd21b24SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 66bbde32d3SSubash Abhinov Kasiviswanathan } 67bbd21b24SSubash Abhinov Kasiviswanathan 68bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 768 - Skip IPv4 UDP packets where sender checksum field is 0 */ 69bbde32d3SSubash Abhinov Kasiviswanathan if (*csum_field == 0 && ip4h->protocol == IPPROTO_UDP) { 70bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_skipped++; 71bbd21b24SSubash Abhinov Kasiviswanathan return 0; 72bbde32d3SSubash Abhinov Kasiviswanathan } 73bbd21b24SSubash Abhinov Kasiviswanathan 74bbd21b24SSubash Abhinov Kasiviswanathan csum_value = ~ntohs(csum_trailer->csum_value); 75bbd21b24SSubash Abhinov Kasiviswanathan hdr_csum = ~ip_fast_csum(ip4h, (int)ip4h->ihl); 76bbd21b24SSubash Abhinov Kasiviswanathan ip_payload_csum = csum16_sub((__force __sum16)csum_value, 77bbd21b24SSubash Abhinov Kasiviswanathan (__force __be16)hdr_csum); 78bbd21b24SSubash Abhinov Kasiviswanathan 79bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = ~csum_tcpudp_magic(ip4h->saddr, ip4h->daddr, 80bbd21b24SSubash Abhinov Kasiviswanathan ntohs(ip4h->tot_len) - ip4h->ihl * 4, 81bbd21b24SSubash Abhinov Kasiviswanathan ip4h->protocol, 0); 82bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)pseudo_csum); 83bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = csum16_add(ip_payload_csum, addend); 84bbd21b24SSubash Abhinov Kasiviswanathan 85bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)*csum_field); 86bbd21b24SSubash Abhinov Kasiviswanathan csum_temp = ~csum16_sub(pseudo_csum, addend); 87bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = (__force u16)csum_temp; 88bbd21b24SSubash Abhinov Kasiviswanathan 89bbd21b24SSubash Abhinov Kasiviswanathan if (unlikely(csum_value_final == 0)) { 90bbd21b24SSubash Abhinov Kasiviswanathan switch (ip4h->protocol) { 91bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_UDP: 92bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 768 - DL4 1's complement rule for UDP csum 0 */ 93bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 94bbd21b24SSubash Abhinov Kasiviswanathan break; 95bbd21b24SSubash Abhinov Kasiviswanathan 96bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_TCP: 97bbd21b24SSubash Abhinov Kasiviswanathan /* DL4 Non-RFC compliant TCP checksum found */ 98bbd21b24SSubash Abhinov Kasiviswanathan if (*csum_field == (__force __sum16)0xFFFF) 99bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 100bbd21b24SSubash Abhinov Kasiviswanathan break; 101bbd21b24SSubash Abhinov Kasiviswanathan } 102bbd21b24SSubash Abhinov Kasiviswanathan } 103bbd21b24SSubash Abhinov Kasiviswanathan 104bbde32d3SSubash Abhinov Kasiviswanathan if (csum_value_final == ntohs((__force __be16)*csum_field)) { 105bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_ok++; 106bbd21b24SSubash Abhinov Kasiviswanathan return 0; 107bbde32d3SSubash Abhinov Kasiviswanathan } else { 108bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_validation_failed++; 109bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 110bbd21b24SSubash Abhinov Kasiviswanathan } 111bbde32d3SSubash Abhinov Kasiviswanathan } 112bbd21b24SSubash Abhinov Kasiviswanathan 113bbd21b24SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 114bbd21b24SSubash Abhinov Kasiviswanathan static int 115bbd21b24SSubash Abhinov Kasiviswanathan rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, 116bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_map_dl_csum_trailer *csum_trailer, 117bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv) 118bbd21b24SSubash Abhinov Kasiviswanathan { 119bbd21b24SSubash Abhinov Kasiviswanathan __sum16 *csum_field, ip6_payload_csum, pseudo_csum, csum_temp; 120bbd21b24SSubash Abhinov Kasiviswanathan u16 csum_value, csum_value_final; 121bbd21b24SSubash Abhinov Kasiviswanathan __be16 ip6_hdr_csum, addend; 122bbd21b24SSubash Abhinov Kasiviswanathan struct ipv6hdr *ip6h; 123bbd21b24SSubash Abhinov Kasiviswanathan void *txporthdr; 124bbd21b24SSubash Abhinov Kasiviswanathan u32 length; 125bbd21b24SSubash Abhinov Kasiviswanathan 126bbd21b24SSubash Abhinov Kasiviswanathan ip6h = (struct ipv6hdr *)(skb->data); 127bbd21b24SSubash Abhinov Kasiviswanathan 128bbd21b24SSubash Abhinov Kasiviswanathan txporthdr = skb->data + sizeof(struct ipv6hdr); 129bbd21b24SSubash Abhinov Kasiviswanathan csum_field = rmnet_map_get_csum_field(ip6h->nexthdr, txporthdr); 130bbd21b24SSubash Abhinov Kasiviswanathan 131bbde32d3SSubash Abhinov Kasiviswanathan if (!csum_field) { 132bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_transport++; 133bbd21b24SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 134bbde32d3SSubash Abhinov Kasiviswanathan } 135bbd21b24SSubash Abhinov Kasiviswanathan 136bbd21b24SSubash Abhinov Kasiviswanathan csum_value = ~ntohs(csum_trailer->csum_value); 137bbd21b24SSubash Abhinov Kasiviswanathan ip6_hdr_csum = (__force __be16) 138bbd21b24SSubash Abhinov Kasiviswanathan ~ntohs((__force __be16)ip_compute_csum(ip6h, 139bbd21b24SSubash Abhinov Kasiviswanathan (int)(txporthdr - (void *)(skb->data)))); 140bbd21b24SSubash Abhinov Kasiviswanathan ip6_payload_csum = csum16_sub((__force __sum16)csum_value, 141bbd21b24SSubash Abhinov Kasiviswanathan ip6_hdr_csum); 142bbd21b24SSubash Abhinov Kasiviswanathan 143bbd21b24SSubash Abhinov Kasiviswanathan length = (ip6h->nexthdr == IPPROTO_UDP) ? 144bbd21b24SSubash Abhinov Kasiviswanathan ntohs(((struct udphdr *)txporthdr)->len) : 145bbd21b24SSubash Abhinov Kasiviswanathan ntohs(ip6h->payload_len); 146bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = ~(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, 147bbd21b24SSubash Abhinov Kasiviswanathan length, ip6h->nexthdr, 0)); 148bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)pseudo_csum); 149bbd21b24SSubash Abhinov Kasiviswanathan pseudo_csum = csum16_add(ip6_payload_csum, addend); 150bbd21b24SSubash Abhinov Kasiviswanathan 151bbd21b24SSubash Abhinov Kasiviswanathan addend = (__force __be16)ntohs((__force __be16)*csum_field); 152bbd21b24SSubash Abhinov Kasiviswanathan csum_temp = ~csum16_sub(pseudo_csum, addend); 153bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = (__force u16)csum_temp; 154bbd21b24SSubash Abhinov Kasiviswanathan 155bbd21b24SSubash Abhinov Kasiviswanathan if (unlikely(csum_value_final == 0)) { 156bbd21b24SSubash Abhinov Kasiviswanathan switch (ip6h->nexthdr) { 157bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_UDP: 158bbd21b24SSubash Abhinov Kasiviswanathan /* RFC 2460 section 8.1 159bbd21b24SSubash Abhinov Kasiviswanathan * DL6 One's complement rule for UDP checksum 0 160bbd21b24SSubash Abhinov Kasiviswanathan */ 161bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 162bbd21b24SSubash Abhinov Kasiviswanathan break; 163bbd21b24SSubash Abhinov Kasiviswanathan 164bbd21b24SSubash Abhinov Kasiviswanathan case IPPROTO_TCP: 165bbd21b24SSubash Abhinov Kasiviswanathan /* DL6 Non-RFC compliant TCP checksum found */ 166bbd21b24SSubash Abhinov Kasiviswanathan if (*csum_field == (__force __sum16)0xFFFF) 167bbd21b24SSubash Abhinov Kasiviswanathan csum_value_final = ~csum_value_final; 168bbd21b24SSubash Abhinov Kasiviswanathan break; 169bbd21b24SSubash Abhinov Kasiviswanathan } 170bbd21b24SSubash Abhinov Kasiviswanathan } 171bbd21b24SSubash Abhinov Kasiviswanathan 172bbde32d3SSubash Abhinov Kasiviswanathan if (csum_value_final == ntohs((__force __be16)*csum_field)) { 173bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_ok++; 174bbd21b24SSubash Abhinov Kasiviswanathan return 0; 175bbde32d3SSubash Abhinov Kasiviswanathan } else { 176bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_validation_failed++; 177bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 178bbd21b24SSubash Abhinov Kasiviswanathan } 179bbde32d3SSubash Abhinov Kasiviswanathan } 180bbd21b24SSubash Abhinov Kasiviswanathan #endif 181bbd21b24SSubash Abhinov Kasiviswanathan 1825eb5f860SSubash Abhinov Kasiviswanathan static void rmnet_map_complement_ipv4_txporthdr_csum_field(void *iphdr) 1835eb5f860SSubash Abhinov Kasiviswanathan { 1845eb5f860SSubash Abhinov Kasiviswanathan struct iphdr *ip4h = (struct iphdr *)iphdr; 1855eb5f860SSubash Abhinov Kasiviswanathan void *txphdr; 1865eb5f860SSubash Abhinov Kasiviswanathan u16 *csum; 1875eb5f860SSubash Abhinov Kasiviswanathan 1885eb5f860SSubash Abhinov Kasiviswanathan txphdr = iphdr + ip4h->ihl * 4; 1895eb5f860SSubash Abhinov Kasiviswanathan 1905eb5f860SSubash Abhinov Kasiviswanathan if (ip4h->protocol == IPPROTO_TCP || ip4h->protocol == IPPROTO_UDP) { 1915eb5f860SSubash Abhinov Kasiviswanathan csum = (u16 *)rmnet_map_get_csum_field(ip4h->protocol, txphdr); 1925eb5f860SSubash Abhinov Kasiviswanathan *csum = ~(*csum); 1935eb5f860SSubash Abhinov Kasiviswanathan } 1945eb5f860SSubash Abhinov Kasiviswanathan } 1955eb5f860SSubash Abhinov Kasiviswanathan 1965eb5f860SSubash Abhinov Kasiviswanathan static void 1975eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv4_ul_csum_header(void *iphdr, 1985eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header, 1995eb5f860SSubash Abhinov Kasiviswanathan struct sk_buff *skb) 2005eb5f860SSubash Abhinov Kasiviswanathan { 20150c62a11SAlex Elder struct iphdr *ip4h = iphdr; 20286ca860eSAlex Elder u16 val; 20386ca860eSAlex Elder 20486ca860eSAlex Elder val = MAP_CSUM_UL_ENABLED_FLAG; 20586ca860eSAlex Elder if (ip4h->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 2335eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv6_ul_csum_header(void *ip6hdr, 2345eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header, 2355eb5f860SSubash Abhinov Kasiviswanathan struct sk_buff *skb) 2365eb5f860SSubash Abhinov Kasiviswanathan { 23750c62a11SAlex Elder struct ipv6hdr *ip6h = ip6hdr; 23886ca860eSAlex Elder u16 val; 23986ca860eSAlex Elder 24086ca860eSAlex Elder val = MAP_CSUM_UL_ENABLED_FLAG; 24186ca860eSAlex Elder if (ip6h->nexthdr == IPPROTO_UDP) 24286ca860eSAlex Elder val |= MAP_CSUM_UL_UDP_FLAG; 24386ca860eSAlex Elder val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK; 2445eb5f860SSubash Abhinov Kasiviswanathan 24550c62a11SAlex Elder ul_header->csum_start_offset = htons(skb_network_header_len(skb)); 24686ca860eSAlex Elder ul_header->csum_info = htons(val); 2475eb5f860SSubash Abhinov Kasiviswanathan 2485eb5f860SSubash Abhinov Kasiviswanathan skb->ip_summed = CHECKSUM_NONE; 2495eb5f860SSubash Abhinov Kasiviswanathan 2505eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_complement_ipv6_txporthdr_csum_field(ip6hdr); 2515eb5f860SSubash Abhinov Kasiviswanathan } 2525eb5f860SSubash Abhinov Kasiviswanathan #endif 2535eb5f860SSubash Abhinov Kasiviswanathan 254ceed73a2SSubash Abhinov Kasiviswanathan /* Adds MAP header to front of skb->data 255ceed73a2SSubash Abhinov Kasiviswanathan * Padding is calculated and set appropriately in MAP header. Mux ID is 256ceed73a2SSubash Abhinov Kasiviswanathan * initialized to 0. 257ceed73a2SSubash Abhinov Kasiviswanathan */ 258ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb, 259ceed73a2SSubash Abhinov Kasiviswanathan int hdrlen, int pad) 260ceed73a2SSubash Abhinov Kasiviswanathan { 261ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *map_header; 262ceed73a2SSubash Abhinov Kasiviswanathan u32 padding, map_datalen; 263ceed73a2SSubash Abhinov Kasiviswanathan u8 *padbytes; 264ceed73a2SSubash Abhinov Kasiviswanathan 265ceed73a2SSubash Abhinov Kasiviswanathan map_datalen = skb->len - hdrlen; 266ceed73a2SSubash Abhinov Kasiviswanathan map_header = (struct rmnet_map_header *) 267ceed73a2SSubash Abhinov Kasiviswanathan skb_push(skb, sizeof(struct rmnet_map_header)); 268ceed73a2SSubash Abhinov Kasiviswanathan memset(map_header, 0, sizeof(struct rmnet_map_header)); 269ceed73a2SSubash Abhinov Kasiviswanathan 270ceed73a2SSubash Abhinov Kasiviswanathan if (pad == RMNET_MAP_NO_PAD_BYTES) { 271ceed73a2SSubash Abhinov Kasiviswanathan map_header->pkt_len = htons(map_datalen); 272ceed73a2SSubash Abhinov Kasiviswanathan return map_header; 273ceed73a2SSubash Abhinov Kasiviswanathan } 274ceed73a2SSubash Abhinov Kasiviswanathan 27516653c16SAlex Elder BUILD_BUG_ON(MAP_PAD_LEN_MASK < 3); 276ceed73a2SSubash Abhinov Kasiviswanathan padding = ALIGN(map_datalen, 4) - map_datalen; 277ceed73a2SSubash Abhinov Kasiviswanathan 278ceed73a2SSubash Abhinov Kasiviswanathan if (padding == 0) 279ceed73a2SSubash Abhinov Kasiviswanathan goto done; 280ceed73a2SSubash Abhinov Kasiviswanathan 281ceed73a2SSubash Abhinov Kasiviswanathan if (skb_tailroom(skb) < padding) 282ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 283ceed73a2SSubash Abhinov Kasiviswanathan 284ceed73a2SSubash Abhinov Kasiviswanathan padbytes = (u8 *)skb_put(skb, padding); 285ceed73a2SSubash Abhinov Kasiviswanathan memset(padbytes, 0, padding); 286ceed73a2SSubash Abhinov Kasiviswanathan 287ceed73a2SSubash Abhinov Kasiviswanathan done: 288ceed73a2SSubash Abhinov Kasiviswanathan map_header->pkt_len = htons(map_datalen + padding); 28916653c16SAlex Elder /* This is a data packet, so the CMD bit is 0 */ 29016653c16SAlex Elder map_header->flags = padding & MAP_PAD_LEN_MASK; 291ceed73a2SSubash Abhinov Kasiviswanathan 292ceed73a2SSubash Abhinov Kasiviswanathan return map_header; 293ceed73a2SSubash Abhinov Kasiviswanathan } 294ceed73a2SSubash Abhinov Kasiviswanathan 295ceed73a2SSubash Abhinov Kasiviswanathan /* Deaggregates a single packet 296ceed73a2SSubash Abhinov Kasiviswanathan * A whole new buffer is allocated for each portion of an aggregated frame. 297ceed73a2SSubash Abhinov Kasiviswanathan * Caller should keep calling deaggregate() on the source skb until 0 is 298ceed73a2SSubash Abhinov Kasiviswanathan * returned, indicating that there are no more packets to deaggregate. Caller 299ceed73a2SSubash Abhinov Kasiviswanathan * is responsible for freeing the original skb. 300ceed73a2SSubash Abhinov Kasiviswanathan */ 301bbd21b24SSubash Abhinov Kasiviswanathan struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb, 302bbd21b24SSubash Abhinov Kasiviswanathan struct rmnet_port *port) 303ceed73a2SSubash Abhinov Kasiviswanathan { 304*e1d9a90aSSharath Chandra Vurukala struct rmnet_map_v5_csum_header *next_hdr = NULL; 305ceed73a2SSubash Abhinov Kasiviswanathan struct rmnet_map_header *maph; 306*e1d9a90aSSharath Chandra Vurukala void *data = skb->data; 307ceed73a2SSubash Abhinov Kasiviswanathan struct sk_buff *skbn; 308*e1d9a90aSSharath Chandra Vurukala u8 nexthdr_type; 309ceed73a2SSubash Abhinov Kasiviswanathan u32 packet_len; 310ceed73a2SSubash Abhinov Kasiviswanathan 311ceed73a2SSubash Abhinov Kasiviswanathan if (skb->len == 0) 312ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 313ceed73a2SSubash Abhinov Kasiviswanathan 314ceed73a2SSubash Abhinov Kasiviswanathan maph = (struct rmnet_map_header *)skb->data; 3159d131d04SAlex Elder packet_len = ntohs(maph->pkt_len) + sizeof(*maph); 316ceed73a2SSubash Abhinov Kasiviswanathan 317*e1d9a90aSSharath Chandra Vurukala if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4) { 318bbd21b24SSubash Abhinov Kasiviswanathan packet_len += sizeof(struct rmnet_map_dl_csum_trailer); 319*e1d9a90aSSharath Chandra Vurukala } else if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV5) { 320*e1d9a90aSSharath Chandra Vurukala if (!(maph->flags & MAP_CMD_FLAG)) { 321*e1d9a90aSSharath Chandra Vurukala packet_len += sizeof(*next_hdr); 322*e1d9a90aSSharath Chandra Vurukala if (maph->flags & MAP_NEXT_HEADER_FLAG) 323*e1d9a90aSSharath Chandra Vurukala next_hdr = data + sizeof(*maph); 324*e1d9a90aSSharath Chandra Vurukala else 325*e1d9a90aSSharath Chandra Vurukala /* Mapv5 data pkt without csum hdr is invalid */ 326*e1d9a90aSSharath Chandra Vurukala return NULL; 327*e1d9a90aSSharath Chandra Vurukala } 328*e1d9a90aSSharath Chandra Vurukala } 329bbd21b24SSubash Abhinov Kasiviswanathan 330ceed73a2SSubash Abhinov Kasiviswanathan if (((int)skb->len - (int)packet_len) < 0) 331ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 332ceed73a2SSubash Abhinov Kasiviswanathan 3331f4f554aSDan Carpenter /* Some hardware can send us empty frames. Catch them */ 3349d131d04SAlex Elder if (!maph->pkt_len) 3351f4f554aSDan Carpenter return NULL; 3361f4f554aSDan Carpenter 337*e1d9a90aSSharath Chandra Vurukala if (next_hdr) { 338*e1d9a90aSSharath Chandra Vurukala nexthdr_type = u8_get_bits(next_hdr->header_info, 339*e1d9a90aSSharath Chandra Vurukala MAPV5_HDRINFO_HDR_TYPE_FMASK); 340*e1d9a90aSSharath Chandra Vurukala if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD) 341*e1d9a90aSSharath Chandra Vurukala return NULL; 342*e1d9a90aSSharath Chandra Vurukala } 343*e1d9a90aSSharath Chandra Vurukala 344ceed73a2SSubash Abhinov Kasiviswanathan skbn = alloc_skb(packet_len + RMNET_MAP_DEAGGR_SPACING, GFP_ATOMIC); 345ceed73a2SSubash Abhinov Kasiviswanathan if (!skbn) 346ceed73a2SSubash Abhinov Kasiviswanathan return NULL; 347ceed73a2SSubash Abhinov Kasiviswanathan 348ceed73a2SSubash Abhinov Kasiviswanathan skb_reserve(skbn, RMNET_MAP_DEAGGR_HEADROOM); 349ceed73a2SSubash Abhinov Kasiviswanathan skb_put(skbn, packet_len); 350ceed73a2SSubash Abhinov Kasiviswanathan memcpy(skbn->data, skb->data, packet_len); 351ceed73a2SSubash Abhinov Kasiviswanathan skb_pull(skb, packet_len); 352ceed73a2SSubash Abhinov Kasiviswanathan 353ceed73a2SSubash Abhinov Kasiviswanathan return skbn; 354ceed73a2SSubash Abhinov Kasiviswanathan } 355bbd21b24SSubash Abhinov Kasiviswanathan 356bbd21b24SSubash Abhinov Kasiviswanathan /* Validates packet checksums. Function takes a pointer to 357bbd21b24SSubash Abhinov Kasiviswanathan * the beginning of a buffer which contains the IP payload + 358bbd21b24SSubash Abhinov Kasiviswanathan * padding + checksum trailer. 359bbd21b24SSubash Abhinov Kasiviswanathan * Only IPv4 and IPv6 are supported along with TCP & UDP. 360bbd21b24SSubash Abhinov Kasiviswanathan * Fragmented or tunneled packets are not supported. 361bbd21b24SSubash Abhinov Kasiviswanathan */ 362bbd21b24SSubash Abhinov Kasiviswanathan int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len) 363bbd21b24SSubash Abhinov Kasiviswanathan { 364bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv = netdev_priv(skb->dev); 365bbd21b24SSubash Abhinov Kasiviswanathan struct rmnet_map_dl_csum_trailer *csum_trailer; 366bbd21b24SSubash Abhinov Kasiviswanathan 367bbde32d3SSubash Abhinov Kasiviswanathan if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) { 368bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_sw++; 369bbd21b24SSubash Abhinov Kasiviswanathan return -EOPNOTSUPP; 370bbde32d3SSubash Abhinov Kasiviswanathan } 371bbd21b24SSubash Abhinov Kasiviswanathan 372bbd21b24SSubash Abhinov Kasiviswanathan csum_trailer = (struct rmnet_map_dl_csum_trailer *)(skb->data + len); 373bbd21b24SSubash Abhinov Kasiviswanathan 374cc1b21baSAlex Elder if (!(csum_trailer->flags & MAP_CSUM_DL_VALID_FLAG)) { 375bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_valid_unset++; 376bbd21b24SSubash Abhinov Kasiviswanathan return -EINVAL; 377bbde32d3SSubash Abhinov Kasiviswanathan } 378bbd21b24SSubash Abhinov Kasiviswanathan 379bbde32d3SSubash Abhinov Kasiviswanathan if (skb->protocol == htons(ETH_P_IP)) { 380bbde32d3SSubash Abhinov Kasiviswanathan return rmnet_map_ipv4_dl_csum_trailer(skb, csum_trailer, priv); 381bbde32d3SSubash Abhinov Kasiviswanathan } else if (skb->protocol == htons(ETH_P_IPV6)) { 382bbd21b24SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 383bbde32d3SSubash Abhinov Kasiviswanathan return rmnet_map_ipv6_dl_csum_trailer(skb, csum_trailer, priv); 384bbd21b24SSubash Abhinov Kasiviswanathan #else 385bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_ip_version++; 386bbd21b24SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 387bbd21b24SSubash Abhinov Kasiviswanathan #endif 388bbde32d3SSubash Abhinov Kasiviswanathan } else { 389bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_ip_version++; 390bbde32d3SSubash Abhinov Kasiviswanathan return -EPROTONOSUPPORT; 391bbde32d3SSubash Abhinov Kasiviswanathan } 392bbd21b24SSubash Abhinov Kasiviswanathan 393bbd21b24SSubash Abhinov Kasiviswanathan return 0; 394bbd21b24SSubash Abhinov Kasiviswanathan } 3955eb5f860SSubash Abhinov Kasiviswanathan 3965eb5f860SSubash Abhinov Kasiviswanathan /* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP 3975eb5f860SSubash Abhinov Kasiviswanathan * packets that are supported for UL checksum offload. 3985eb5f860SSubash Abhinov Kasiviswanathan */ 3995eb5f860SSubash Abhinov Kasiviswanathan void rmnet_map_checksum_uplink_packet(struct sk_buff *skb, 4005eb5f860SSubash Abhinov Kasiviswanathan struct net_device *orig_dev) 4015eb5f860SSubash Abhinov Kasiviswanathan { 402bbde32d3SSubash Abhinov Kasiviswanathan struct rmnet_priv *priv = netdev_priv(orig_dev); 4035eb5f860SSubash Abhinov Kasiviswanathan struct rmnet_map_ul_csum_header *ul_header; 4045eb5f860SSubash Abhinov Kasiviswanathan void *iphdr; 4055eb5f860SSubash Abhinov Kasiviswanathan 4065eb5f860SSubash Abhinov Kasiviswanathan ul_header = (struct rmnet_map_ul_csum_header *) 4075eb5f860SSubash Abhinov Kasiviswanathan skb_push(skb, sizeof(struct rmnet_map_ul_csum_header)); 4085eb5f860SSubash Abhinov Kasiviswanathan 4095eb5f860SSubash Abhinov Kasiviswanathan if (unlikely(!(orig_dev->features & 4105eb5f860SSubash Abhinov Kasiviswanathan (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)))) 4115eb5f860SSubash Abhinov Kasiviswanathan goto sw_csum; 4125eb5f860SSubash Abhinov Kasiviswanathan 4135eb5f860SSubash Abhinov Kasiviswanathan if (skb->ip_summed == CHECKSUM_PARTIAL) { 4145eb5f860SSubash Abhinov Kasiviswanathan iphdr = (char *)ul_header + 4155eb5f860SSubash Abhinov Kasiviswanathan sizeof(struct rmnet_map_ul_csum_header); 4165eb5f860SSubash Abhinov Kasiviswanathan 4175eb5f860SSubash Abhinov Kasiviswanathan if (skb->protocol == htons(ETH_P_IP)) { 4185eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv4_ul_csum_header(iphdr, ul_header, skb); 4195eb5f860SSubash Abhinov Kasiviswanathan return; 4205eb5f860SSubash Abhinov Kasiviswanathan } else if (skb->protocol == htons(ETH_P_IPV6)) { 4215eb5f860SSubash Abhinov Kasiviswanathan #if IS_ENABLED(CONFIG_IPV6) 4225eb5f860SSubash Abhinov Kasiviswanathan rmnet_map_ipv6_ul_csum_header(iphdr, ul_header, skb); 4235eb5f860SSubash Abhinov Kasiviswanathan return; 4245eb5f860SSubash Abhinov Kasiviswanathan #else 425bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_ip_version++; 4265eb5f860SSubash Abhinov Kasiviswanathan goto sw_csum; 4275eb5f860SSubash Abhinov Kasiviswanathan #endif 428bbde32d3SSubash Abhinov Kasiviswanathan } else { 429bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_err_invalid_ip_version++; 4305eb5f860SSubash Abhinov Kasiviswanathan } 4315eb5f860SSubash Abhinov Kasiviswanathan } 4325eb5f860SSubash Abhinov Kasiviswanathan 4335eb5f860SSubash Abhinov Kasiviswanathan sw_csum: 43486ca860eSAlex Elder memset(ul_header, 0, sizeof(*ul_header)); 435bbde32d3SSubash Abhinov Kasiviswanathan 436bbde32d3SSubash Abhinov Kasiviswanathan priv->stats.csum_sw++; 4375eb5f860SSubash Abhinov Kasiviswanathan } 438*e1d9a90aSSharath Chandra Vurukala 439*e1d9a90aSSharath Chandra Vurukala /* Process a MAPv5 packet header */ 440*e1d9a90aSSharath Chandra Vurukala int rmnet_map_process_next_hdr_packet(struct sk_buff *skb, 441*e1d9a90aSSharath Chandra Vurukala u16 len) 442*e1d9a90aSSharath Chandra Vurukala { 443*e1d9a90aSSharath Chandra Vurukala struct rmnet_priv *priv = netdev_priv(skb->dev); 444*e1d9a90aSSharath Chandra Vurukala struct rmnet_map_v5_csum_header *next_hdr; 445*e1d9a90aSSharath Chandra Vurukala u8 nexthdr_type; 446*e1d9a90aSSharath Chandra Vurukala 447*e1d9a90aSSharath Chandra Vurukala next_hdr = (struct rmnet_map_v5_csum_header *)(skb->data + 448*e1d9a90aSSharath Chandra Vurukala sizeof(struct rmnet_map_header)); 449*e1d9a90aSSharath Chandra Vurukala 450*e1d9a90aSSharath Chandra Vurukala nexthdr_type = u8_get_bits(next_hdr->header_info, 451*e1d9a90aSSharath Chandra Vurukala MAPV5_HDRINFO_HDR_TYPE_FMASK); 452*e1d9a90aSSharath Chandra Vurukala 453*e1d9a90aSSharath Chandra Vurukala if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD) 454*e1d9a90aSSharath Chandra Vurukala return -EINVAL; 455*e1d9a90aSSharath Chandra Vurukala 456*e1d9a90aSSharath Chandra Vurukala if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) { 457*e1d9a90aSSharath Chandra Vurukala priv->stats.csum_sw++; 458*e1d9a90aSSharath Chandra Vurukala } else if (next_hdr->csum_info & MAPV5_CSUMINFO_VALID_FLAG) { 459*e1d9a90aSSharath Chandra Vurukala priv->stats.csum_ok++; 460*e1d9a90aSSharath Chandra Vurukala skb->ip_summed = CHECKSUM_UNNECESSARY; 461*e1d9a90aSSharath Chandra Vurukala } else { 462*e1d9a90aSSharath Chandra Vurukala priv->stats.csum_valid_unset++; 463*e1d9a90aSSharath Chandra Vurukala } 464*e1d9a90aSSharath Chandra Vurukala 465*e1d9a90aSSharath Chandra Vurukala /* Pull csum v5 header */ 466*e1d9a90aSSharath Chandra Vurukala skb_pull(skb, sizeof(*next_hdr)); 467*e1d9a90aSSharath Chandra Vurukala 468*e1d9a90aSSharath Chandra Vurukala return 0; 469*e1d9a90aSSharath Chandra Vurukala } 470