Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 520 insertions, 0 deletions

diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
new file mode 100644
index 000000000..ba194698c
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
@@ -0,0 +1,520 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2013-2018, 2021, The Linux Foundation. All rights reserved.
+ *
+ * RMNET Data MAP protocol
+ */
+
+#include <linux/netdevice.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <net/ip6_checksum.h>
+#include <linux/bitfield.h>
+#include "rmnet_config.h"
+#include "rmnet_map.h"
+#include "rmnet_private.h"
+
+#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)
+{
+	if (protocol == IPPROTO_TCP)
+		return &((struct tcphdr *)txporthdr)->check;
+
+	if (protocol == IPPROTO_UDP)
+		return &((struct udphdr *)txporthdr)->check;
+
+	return NULL;
+}
+
+static int
+rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb,
+			       struct rmnet_map_dl_csum_trailer *csum_trailer,
+			       struct rmnet_priv *priv)
+{
+	struct iphdr *ip4h = (struct iphdr *)skb->data;
+	void *txporthdr = skb->data + ip4h->ihl * 4;
+	__sum16 *csum_field, pseudo_csum;
+	__sum16 ip_payload_csum;
+
+	/* Computing the checksum over just the IPv4 header--including its
+	 * checksum field--should yield 0.  If it doesn't, the IP header
+	 * is bad, so return an error and let the IP layer drop it.
+	 */
+	if (ip_fast_csum(ip4h, ip4h->ihl)) {
+		priv->stats.csum_ip4_header_bad++;
+		return -EINVAL;
+	}
+
+	/* We don't support checksum offload on IPv4 fragments */
+	if (ip_is_fragment(ip4h)) {
+		priv->stats.csum_fragmented_pkt++;
+		return -EOPNOTSUPP;
+	}
+
+	/* Checksum offload is only supported for UDP and TCP protocols */
+	csum_field = rmnet_map_get_csum_field(ip4h->protocol, txporthdr);
+	if (!csum_field) {
+		priv->stats.csum_err_invalid_transport++;
+		return -EPROTONOSUPPORT;
+	}
+
+	/* RFC 768: UDP checksum is optional for IPv4, and is 0 if unused */
+	if (!*csum_field && ip4h->protocol == IPPROTO_UDP) {
+		priv->stats.csum_skipped++;
+		return 0;
+	}
+
+	/* The checksum value in the trailer is computed over the entire
+	 * IP packet, including the IP header and payload.  To derive the
+	 * transport checksum from this, we first subract the contribution
+	 * of the IP header from the trailer checksum.  We then add the
+	 * checksum computed over the pseudo header.
+	 *
+	 * We verified above that the IP header contributes zero to the
+	 * trailer checksum.  Therefore the checksum in the trailer is
+	 * just the checksum computed over the IP payload.
+
+	 * If the IP payload arrives intact, adding the pseudo header
+	 * checksum to the IP payload checksum will yield 0xffff (negative
+	 * zero).  This means the trailer checksum and the pseudo checksum
+	 * are additive inverses of each other.  Put another way, the
+	 * message passes the checksum test if the trailer checksum value
+	 * is the negated pseudo header checksum.
+	 *
+	 * Knowing this, we don't even need to examine the transport
+	 * header checksum value; it is already accounted for in the
+	 * checksum value found in the trailer.
+	 */
+	ip_payload_csum = csum_trailer->csum_value;
+
+	pseudo_csum = csum_tcpudp_magic(ip4h->saddr, ip4h->daddr,
+					ntohs(ip4h->tot_len) - ip4h->ihl * 4,
+					ip4h->protocol, 0);
+
+	/* The cast is required to ensure only the low 16 bits are examined */
+	if (ip_payload_csum != (__sum16)~pseudo_csum) {
+		priv->stats.csum_validation_failed++;
+		return -EINVAL;
+	}
+
+	priv->stats.csum_ok++;
+	return 0;
+}
+
+#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,
+			       struct rmnet_priv *priv)
+{
+	struct ipv6hdr *ip6h = (struct ipv6hdr *)skb->data;
+	void *txporthdr = skb->data + sizeof(*ip6h);
+	__sum16 *csum_field, pseudo_csum;
+	__sum16 ip6_payload_csum;
+	__be16 ip_header_csum;
+
+	/* Checksum offload is only supported for UDP and TCP protocols;
+	 * the packet cannot include any IPv6 extension headers
+	 */
+	csum_field = rmnet_map_get_csum_field(ip6h->nexthdr, txporthdr);
+	if (!csum_field) {
+		priv->stats.csum_err_invalid_transport++;
+		return -EPROTONOSUPPORT;
+	}
+
+	/* The checksum value in the trailer is computed over the entire
+	 * IP packet, including the IP header and payload.  To derive the
+	 * transport checksum from this, we first subract the contribution
+	 * of the IP header from the trailer checksum.  We then add the
+	 * checksum computed over the pseudo header.
+	 */
+	ip_header_csum = (__force __be16)ip_fast_csum(ip6h, sizeof(*ip6h) / 4);
+	ip6_payload_csum = csum16_sub(csum_trailer->csum_value, ip_header_csum);
+
+	pseudo_csum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
+				      ntohs(ip6h->payload_len),
+				      ip6h->nexthdr, 0);
+
+	/* It's sufficient to compare the IP payload checksum with the
+	 * negated pseudo checksum to determine whether the packet
+	 * checksum was good.  (See further explanation in comments
+	 * in rmnet_map_ipv4_dl_csum_trailer()).
+	 *
+	 * The cast is required to ensure only the low 16 bits are
+	 * examined.
+	 */
+	if (ip6_payload_csum != (__sum16)~pseudo_csum) {
+		priv->stats.csum_validation_failed++;
+		return -EINVAL;
+	}
+
+	priv->stats.csum_ok++;
+	return 0;
+}
+#else
+static int
+rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb,
+			       struct rmnet_map_dl_csum_trailer *csum_trailer,
+			       struct rmnet_priv *priv)
+{
+	return 0;
+}
+#endif
+
+static void rmnet_map_complement_ipv4_txporthdr_csum_field(struct iphdr *ip4h)
+{
+	void *txphdr;
+	u16 *csum;
+
+	txphdr = (void *)ip4h + 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(struct iphdr *iphdr,
+			      struct rmnet_map_ul_csum_header *ul_header,
+			      struct sk_buff *skb)
+{
+	u16 val;
+
+	val = MAP_CSUM_UL_ENABLED_FLAG;
+	if (iphdr->protocol == IPPROTO_UDP)
+		val |= MAP_CSUM_UL_UDP_FLAG;
+	val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK;
+
+	ul_header->csum_start_offset = htons(skb_network_header_len(skb));
+	ul_header->csum_info = htons(val);
+
+	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(struct ipv6hdr *ip6h)
+{
+	void *txphdr;
+	u16 *csum;
+
+	txphdr = ip6h + 1;
+
+	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(struct ipv6hdr *ipv6hdr,
+			      struct rmnet_map_ul_csum_header *ul_header,
+			      struct sk_buff *skb)
+{
+	u16 val;
+
+	val = MAP_CSUM_UL_ENABLED_FLAG;
+	if (ipv6hdr->nexthdr == IPPROTO_UDP)
+		val |= MAP_CSUM_UL_UDP_FLAG;
+	val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK;
+
+	ul_header->csum_start_offset = htons(skb_network_header_len(skb));
+	ul_header->csum_info = htons(val);
+
+	skb->ip_summed = CHECKSUM_NONE;
+
+	rmnet_map_complement_ipv6_txporthdr_csum_field(ipv6hdr);
+}
+#else
+static void
+rmnet_map_ipv6_ul_csum_header(void *ip6hdr,
+			      struct rmnet_map_ul_csum_header *ul_header,
+			      struct sk_buff *skb)
+{
+}
+#endif
+
+static void rmnet_map_v5_checksum_uplink_packet(struct sk_buff *skb,
+						struct rmnet_port *port,
+						struct net_device *orig_dev)
+{
+	struct rmnet_priv *priv = netdev_priv(orig_dev);
+	struct rmnet_map_v5_csum_header *ul_header;
+
+	ul_header = skb_push(skb, sizeof(*ul_header));
+	memset(ul_header, 0, sizeof(*ul_header));
+	ul_header->header_info = u8_encode_bits(RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD,
+						MAPV5_HDRINFO_HDR_TYPE_FMASK);
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL) {
+		void *iph = ip_hdr(skb);
+		__sum16 *check;
+		void *trans;
+		u8 proto;
+
+		if (skb->protocol == htons(ETH_P_IP)) {
+			u16 ip_len = ((struct iphdr *)iph)->ihl * 4;
+
+			proto = ((struct iphdr *)iph)->protocol;
+			trans = iph + ip_len;
+		} else if (IS_ENABLED(CONFIG_IPV6) &&
+			   skb->protocol == htons(ETH_P_IPV6)) {
+			u16 ip_len = sizeof(struct ipv6hdr);
+
+			proto = ((struct ipv6hdr *)iph)->nexthdr;
+			trans = iph + ip_len;
+		} else {
+			priv->stats.csum_err_invalid_ip_version++;
+			goto sw_csum;
+		}
+
+		check = rmnet_map_get_csum_field(proto, trans);
+		if (check) {
+			skb->ip_summed = CHECKSUM_NONE;
+			/* Ask for checksum offloading */
+			ul_header->csum_info |= MAPV5_CSUMINFO_VALID_FLAG;
+			priv->stats.csum_hw++;
+			return;
+		}
+	}
+
+sw_csum:
+	priv->stats.csum_sw++;
+}
+
+/* Adds MAP header to front of skb->data
+ * Padding is calculated and set appropriately in MAP header. Mux ID is
+ * initialized to 0.
+ */
+struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
+						  int hdrlen,
+						  struct rmnet_port *port,
+						  int pad)
+{
+	struct rmnet_map_header *map_header;
+	u32 padding, map_datalen;
+
+	map_datalen = skb->len - hdrlen;
+	map_header = (struct rmnet_map_header *)
+			skb_push(skb, sizeof(struct rmnet_map_header));
+	memset(map_header, 0, sizeof(struct rmnet_map_header));
+
+	/* Set next_hdr bit for csum offload packets */
+	if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV5)
+		map_header->flags |= MAP_NEXT_HEADER_FLAG;
+
+	if (pad == RMNET_MAP_NO_PAD_BYTES) {
+		map_header->pkt_len = htons(map_datalen);
+		return map_header;
+	}
+
+	BUILD_BUG_ON(MAP_PAD_LEN_MASK < 3);
+	padding = ALIGN(map_datalen, 4) - map_datalen;
+
+	if (padding == 0)
+		goto done;
+
+	if (skb_tailroom(skb) < padding)
+		return NULL;
+
+	skb_put_zero(skb, padding);
+
+done:
+	map_header->pkt_len = htons(map_datalen + padding);
+	/* This is a data packet, so the CMD bit is 0 */
+	map_header->flags = padding & MAP_PAD_LEN_MASK;
+
+	return map_header;
+}
+
+/* Deaggregates a single packet
+ * A whole new buffer is allocated for each portion of an aggregated frame.
+ * Caller should keep calling deaggregate() on the source skb until 0 is
+ * 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 rmnet_port *port)
+{
+	struct rmnet_map_v5_csum_header *next_hdr = NULL;
+	struct rmnet_map_header *maph;
+	void *data = skb->data;
+	struct sk_buff *skbn;
+	u8 nexthdr_type;
+	u32 packet_len;
+
+	if (skb->len == 0)
+		return NULL;
+
+	maph = (struct rmnet_map_header *)skb->data;
+	packet_len = ntohs(maph->pkt_len) + sizeof(*maph);
+
+	if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4) {
+		packet_len += sizeof(struct rmnet_map_dl_csum_trailer);
+	} else if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV5) {
+		if (!(maph->flags & MAP_CMD_FLAG)) {
+			packet_len += sizeof(*next_hdr);
+			if (maph->flags & MAP_NEXT_HEADER_FLAG)
+				next_hdr = data + sizeof(*maph);
+			else
+				/* Mapv5 data pkt without csum hdr is invalid */
+				return NULL;
+		}
+	}
+
+	if (((int)skb->len - (int)packet_len) < 0)
+		return NULL;
+
+	/* Some hardware can send us empty frames. Catch them */
+	if (!maph->pkt_len)
+		return NULL;
+
+	if (next_hdr) {
+		nexthdr_type = u8_get_bits(next_hdr->header_info,
+					   MAPV5_HDRINFO_HDR_TYPE_FMASK);
+		if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD)
+			return NULL;
+	}
+
+	skbn = alloc_skb(packet_len + RMNET_MAP_DEAGGR_SPACING, GFP_ATOMIC);
+	if (!skbn)
+		return NULL;
+
+	skb_reserve(skbn, RMNET_MAP_DEAGGR_HEADROOM);
+	skb_put(skbn, packet_len);
+	memcpy(skbn->data, skb->data, packet_len);
+	skb_pull(skb, packet_len);
+
+	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_priv *priv = netdev_priv(skb->dev);
+	struct rmnet_map_dl_csum_trailer *csum_trailer;
+
+	if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) {
+		priv->stats.csum_sw++;
+		return -EOPNOTSUPP;
+	}
+
+	csum_trailer = (struct rmnet_map_dl_csum_trailer *)(skb->data + len);
+
+	if (!(csum_trailer->flags & MAP_CSUM_DL_VALID_FLAG)) {
+		priv->stats.csum_valid_unset++;
+		return -EINVAL;
+	}
+
+	if (skb->protocol == htons(ETH_P_IP))
+		return rmnet_map_ipv4_dl_csum_trailer(skb, csum_trailer, priv);
+
+	if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6))
+		return rmnet_map_ipv6_dl_csum_trailer(skb, csum_trailer, priv);
+
+	priv->stats.csum_err_invalid_ip_version++;
+
+	return -EPROTONOSUPPORT;
+}
+
+static void rmnet_map_v4_checksum_uplink_packet(struct sk_buff *skb,
+						struct net_device *orig_dev)
+{
+	struct rmnet_priv *priv = netdev_priv(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)
+		goto sw_csum;
+
+	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);
+		priv->stats.csum_hw++;
+		return;
+	}
+
+	if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) {
+		rmnet_map_ipv6_ul_csum_header(iphdr, ul_header, skb);
+		priv->stats.csum_hw++;
+		return;
+	}
+
+	priv->stats.csum_err_invalid_ip_version++;
+
+sw_csum:
+	memset(ul_header, 0, sizeof(*ul_header));
+
+	priv->stats.csum_sw++;
+}
+
+/* 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 rmnet_port *port,
+				      struct net_device *orig_dev,
+				      int csum_type)
+{
+	switch (csum_type) {
+	case RMNET_FLAGS_EGRESS_MAP_CKSUMV4:
+		rmnet_map_v4_checksum_uplink_packet(skb, orig_dev);
+		break;
+	case RMNET_FLAGS_EGRESS_MAP_CKSUMV5:
+		rmnet_map_v5_checksum_uplink_packet(skb, port, orig_dev);
+		break;
+	default:
+		break;
+	}
+}
+
+/* Process a MAPv5 packet header */
+int rmnet_map_process_next_hdr_packet(struct sk_buff *skb,
+				      u16 len)
+{
+	struct rmnet_priv *priv = netdev_priv(skb->dev);
+	struct rmnet_map_v5_csum_header *next_hdr;
+	u8 nexthdr_type;
+
+	next_hdr = (struct rmnet_map_v5_csum_header *)(skb->data +
+			sizeof(struct rmnet_map_header));
+
+	nexthdr_type = u8_get_bits(next_hdr->header_info,
+				   MAPV5_HDRINFO_HDR_TYPE_FMASK);
+
+	if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD)
+		return -EINVAL;
+
+	if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) {
+		priv->stats.csum_sw++;
+	} else if (next_hdr->csum_info & MAPV5_CSUMINFO_VALID_FLAG) {
+		priv->stats.csum_ok++;
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+	} else {
+		priv->stats.csum_valid_unset++;
+	}
+
+	/* Pull csum v5 header */
+	skb_pull(skb, sizeof(*next_hdr));
+
+	return 0;
+}