diff options
Diffstat (limited to 'drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c')
| -rw-r--r-- | drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c | 309 |
1 files changed, 305 insertions, 4 deletions
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c index 86b8c758f94e..c74a6c56d315 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c @@ -14,6 +14,9 @@ */ #include <linux/netdevice.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <net/ip6_checksum.h> #include "rmnet_config.h" #include "rmnet_map.h" #include "rmnet_private.h" @@ -21,6 +24,233 @@ #define RMNET_MAP_DEAGGR_SPACING 64 #define RMNET_MAP_DEAGGR_HEADROOM (RMNET_MAP_DEAGGR_SPACING / 2) +static __sum16 *rmnet_map_get_csum_field(unsigned char protocol, + const void *txporthdr) +{ + __sum16 *check = NULL; + + switch (protocol) { + case IPPROTO_TCP: + check = &(((struct tcphdr *)txporthdr)->check); + break; + + case IPPROTO_UDP: + check = &(((struct udphdr *)txporthdr)->check); + break; + + default: + check = NULL; + break; + } + + return check; +} + +static int +rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb, + struct rmnet_map_dl_csum_trailer *csum_trailer) +{ + __sum16 *csum_field, csum_temp, pseudo_csum, hdr_csum, ip_payload_csum; + u16 csum_value, csum_value_final; + struct iphdr *ip4h; + void *txporthdr; + __be16 addend; + + ip4h = (struct iphdr *)(skb->data); + if ((ntohs(ip4h->frag_off) & IP_MF) || + ((ntohs(ip4h->frag_off) & IP_OFFSET) > 0)) + return -EOPNOTSUPP; + + txporthdr = skb->data + ip4h->ihl * 4; + + csum_field = rmnet_map_get_csum_field(ip4h->protocol, txporthdr); + + if (!csum_field) + return -EPROTONOSUPPORT; + + /* RFC 768 - Skip IPv4 UDP packets where sender checksum field is 0 */ + if (*csum_field == 0 && ip4h->protocol == IPPROTO_UDP) + return 0; + + csum_value = ~ntohs(csum_trailer->csum_value); + hdr_csum = ~ip_fast_csum(ip4h, (int)ip4h->ihl); + ip_payload_csum = csum16_sub((__force __sum16)csum_value, + (__force __be16)hdr_csum); + + pseudo_csum = ~csum_tcpudp_magic(ip4h->saddr, ip4h->daddr, + ntohs(ip4h->tot_len) - ip4h->ihl * 4, + ip4h->protocol, 0); + addend = (__force __be16)ntohs((__force __be16)pseudo_csum); + pseudo_csum = csum16_add(ip_payload_csum, addend); + + addend = (__force __be16)ntohs((__force __be16)*csum_field); + csum_temp = ~csum16_sub(pseudo_csum, addend); + csum_value_final = (__force u16)csum_temp; + + if (unlikely(csum_value_final == 0)) { + switch (ip4h->protocol) { + case IPPROTO_UDP: + /* RFC 768 - DL4 1's complement rule for UDP csum 0 */ + csum_value_final = ~csum_value_final; + break; + + case IPPROTO_TCP: + /* DL4 Non-RFC compliant TCP checksum found */ + if (*csum_field == (__force __sum16)0xFFFF) + csum_value_final = ~csum_value_final; + break; + } + } + + if (csum_value_final == ntohs((__force __be16)*csum_field)) + return 0; + else + return -EINVAL; +} + +#if IS_ENABLED(CONFIG_IPV6) +static int +rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb, + struct rmnet_map_dl_csum_trailer *csum_trailer) +{ + __sum16 *csum_field, ip6_payload_csum, pseudo_csum, csum_temp; + u16 csum_value, csum_value_final; + __be16 ip6_hdr_csum, addend; + struct ipv6hdr *ip6h; + void *txporthdr; + u32 length; + + ip6h = (struct ipv6hdr *)(skb->data); + + txporthdr = skb->data + sizeof(struct ipv6hdr); + csum_field = rmnet_map_get_csum_field(ip6h->nexthdr, txporthdr); + + if (!csum_field) + return -EPROTONOSUPPORT; + + csum_value = ~ntohs(csum_trailer->csum_value); + ip6_hdr_csum = (__force __be16) + ~ntohs((__force __be16)ip_compute_csum(ip6h, + (int)(txporthdr - (void *)(skb->data)))); + ip6_payload_csum = csum16_sub((__force __sum16)csum_value, + ip6_hdr_csum); + + length = (ip6h->nexthdr == IPPROTO_UDP) ? + ntohs(((struct udphdr *)txporthdr)->len) : + ntohs(ip6h->payload_len); + pseudo_csum = ~(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, + length, ip6h->nexthdr, 0)); + addend = (__force __be16)ntohs((__force __be16)pseudo_csum); + pseudo_csum = csum16_add(ip6_payload_csum, addend); + + addend = (__force __be16)ntohs((__force __be16)*csum_field); + csum_temp = ~csum16_sub(pseudo_csum, addend); + csum_value_final = (__force u16)csum_temp; + + if (unlikely(csum_value_final == 0)) { + switch (ip6h->nexthdr) { + case IPPROTO_UDP: + /* RFC 2460 section 8.1 + * DL6 One's complement rule for UDP checksum 0 + */ + csum_value_final = ~csum_value_final; + break; + + case IPPROTO_TCP: + /* DL6 Non-RFC compliant TCP checksum found */ + if (*csum_field == (__force __sum16)0xFFFF) + csum_value_final = ~csum_value_final; + break; + } + } + + if (csum_value_final == ntohs((__force __be16)*csum_field)) + return 0; + else + return -EINVAL; +} +#endif + +static void rmnet_map_complement_ipv4_txporthdr_csum_field(void *iphdr) +{ + struct iphdr *ip4h = (struct iphdr *)iphdr; + void *txphdr; + u16 *csum; + + txphdr = iphdr + ip4h->ihl * 4; + + if (ip4h->protocol == IPPROTO_TCP || ip4h->protocol == IPPROTO_UDP) { + csum = (u16 *)rmnet_map_get_csum_field(ip4h->protocol, txphdr); + *csum = ~(*csum); + } +} + +static void +rmnet_map_ipv4_ul_csum_header(void *iphdr, + struct rmnet_map_ul_csum_header *ul_header, + struct sk_buff *skb) +{ + struct iphdr *ip4h = (struct iphdr *)iphdr; + __be16 *hdr = (__be16 *)ul_header, offset; + + offset = htons((__force u16)(skb_transport_header(skb) - + (unsigned char *)iphdr)); + ul_header->csum_start_offset = offset; + ul_header->csum_insert_offset = skb->csum_offset; + ul_header->csum_enabled = 1; + if (ip4h->protocol == IPPROTO_UDP) + ul_header->udp_ip4_ind = 1; + else + ul_header->udp_ip4_ind = 0; + + /* Changing remaining fields to network order */ + hdr++; + *hdr = htons((__force u16)*hdr); + + skb->ip_summed = CHECKSUM_NONE; + + rmnet_map_complement_ipv4_txporthdr_csum_field(iphdr); +} + +#if IS_ENABLED(CONFIG_IPV6) +static void rmnet_map_complement_ipv6_txporthdr_csum_field(void *ip6hdr) +{ + struct ipv6hdr *ip6h = (struct ipv6hdr *)ip6hdr; + void *txphdr; + u16 *csum; + + txphdr = ip6hdr + sizeof(struct ipv6hdr); + + if (ip6h->nexthdr == IPPROTO_TCP || ip6h->nexthdr == IPPROTO_UDP) { + csum = (u16 *)rmnet_map_get_csum_field(ip6h->nexthdr, txphdr); + *csum = ~(*csum); + } +} + +static void +rmnet_map_ipv6_ul_csum_header(void *ip6hdr, + struct rmnet_map_ul_csum_header *ul_header, + struct sk_buff *skb) +{ + __be16 *hdr = (__be16 *)ul_header, offset; + + offset = htons((__force u16)(skb_transport_header(skb) - + (unsigned char *)ip6hdr)); + ul_header->csum_start_offset = offset; + ul_header->csum_insert_offset = skb->csum_offset; + ul_header->csum_enabled = 1; + ul_header->udp_ip4_ind = 0; + + /* Changing remaining fields to network order */ + hdr++; + *hdr = htons((__force u16)*hdr); + + skb->ip_summed = CHECKSUM_NONE; + + rmnet_map_complement_ipv6_txporthdr_csum_field(ip6hdr); +} +#endif + /* Adds MAP header to front of skb->data * Padding is calculated and set appropriately in MAP header. Mux ID is * initialized to 0. @@ -32,9 +262,6 @@ struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb, u32 padding, map_datalen; u8 *padbytes; - if (skb_headroom(skb) < sizeof(struct rmnet_map_header)) - return NULL; - map_datalen = skb->len - hdrlen; map_header = (struct rmnet_map_header *) skb_push(skb, sizeof(struct rmnet_map_header)); @@ -69,7 +296,8 @@ done: * returned, indicating that there are no more packets to deaggregate. Caller * is responsible for freeing the original skb. */ -struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb) +struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb, + struct rmnet_port *port) { struct rmnet_map_header *maph; struct sk_buff *skbn; @@ -81,6 +309,9 @@ struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb) maph = (struct rmnet_map_header *)skb->data; packet_len = ntohs(maph->pkt_len) + sizeof(struct rmnet_map_header); + if (port->data_format & RMNET_INGRESS_FORMAT_MAP_CKSUMV4) + packet_len += sizeof(struct rmnet_map_dl_csum_trailer); + if (((int)skb->len - (int)packet_len) < 0) return NULL; @@ -100,3 +331,73 @@ struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb) return skbn; } + +/* Validates packet checksums. Function takes a pointer to + * the beginning of a buffer which contains the IP payload + + * padding + checksum trailer. + * Only IPv4 and IPv6 are supported along with TCP & UDP. + * Fragmented or tunneled packets are not supported. + */ +int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len) +{ + struct rmnet_map_dl_csum_trailer *csum_trailer; + + if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) + return -EOPNOTSUPP; + + csum_trailer = (struct rmnet_map_dl_csum_trailer *)(skb->data + len); + + if (!csum_trailer->valid) + return -EINVAL; + + if (skb->protocol == htons(ETH_P_IP)) + return rmnet_map_ipv4_dl_csum_trailer(skb, csum_trailer); + else if (skb->protocol == htons(ETH_P_IPV6)) +#if IS_ENABLED(CONFIG_IPV6) + return rmnet_map_ipv6_dl_csum_trailer(skb, csum_trailer); +#else + return -EPROTONOSUPPORT; +#endif + + return 0; +} + +/* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP + * packets that are supported for UL checksum offload. + */ +void rmnet_map_checksum_uplink_packet(struct sk_buff *skb, + struct net_device *orig_dev) +{ + struct rmnet_map_ul_csum_header *ul_header; + void *iphdr; + + ul_header = (struct rmnet_map_ul_csum_header *) + skb_push(skb, sizeof(struct rmnet_map_ul_csum_header)); + + if (unlikely(!(orig_dev->features & + (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)))) + goto sw_csum; + + if (skb->ip_summed == CHECKSUM_PARTIAL) { + iphdr = (char *)ul_header + + sizeof(struct rmnet_map_ul_csum_header); + + if (skb->protocol == htons(ETH_P_IP)) { + rmnet_map_ipv4_ul_csum_header(iphdr, ul_header, skb); + return; + } else if (skb->protocol == htons(ETH_P_IPV6)) { +#if IS_ENABLED(CONFIG_IPV6) + rmnet_map_ipv6_ul_csum_header(iphdr, ul_header, skb); + return; +#else + goto sw_csum; +#endif + } + } + +sw_csum: + ul_header->csum_start_offset = 0; + ul_header->csum_insert_offset = 0; + ul_header->csum_enabled = 0; + ul_header->udp_ip4_ind = 0; +} |