From ffe387740bbe88dd88bbe04d6375902708003d6e Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Fri, 7 Jul 2017 17:25:00 +0200 Subject: net: add packet mangeling patch Signed-off-by: Felix Fietkau --- include/linux/netdevice.h | 11 +++++++++++ include/linux/skbuff.h | 14 ++++---------- net/Kconfig | 6 ++++++ net/core/dev.c | 18 ++++++++++++++---- net/core/skbuff.c | 17 +++++++++++++++++ net/ethernet/eth.c | 6 ++++++ 6 files changed, 58 insertions(+), 14 deletions(-) --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1540,6 +1540,7 @@ enum netdev_priv_flags { IFF_FAILOVER_SLAVE = 1<<28, IFF_L3MDEV_RX_HANDLER = 1<<29, IFF_LIVE_RENAME_OK = 1<<30, + IFF_NO_IP_ALIGN = 1<<31, }; #define IFF_802_1Q_VLAN IFF_802_1Q_VLAN @@ -1572,6 +1573,7 @@ enum netdev_priv_flags { #define IFF_FAILOVER_SLAVE IFF_FAILOVER_SLAVE #define IFF_L3MDEV_RX_HANDLER IFF_L3MDEV_RX_HANDLER #define IFF_LIVE_RENAME_OK IFF_LIVE_RENAME_OK +#define IFF_NO_IP_ALIGN IFF_NO_IP_ALIGN /* Specifies the type of the struct net_device::ml_priv pointer */ enum netdev_ml_priv_type { @@ -1882,6 +1884,11 @@ struct net_device { const struct tlsdev_ops *tlsdev_ops; #endif +#ifdef CONFIG_ETHERNET_PACKET_MANGLE + void (*eth_mangle_rx)(struct net_device *dev, struct sk_buff *skb); + struct sk_buff *(*eth_mangle_tx)(struct net_device *dev, struct sk_buff *skb); +#endif + const struct header_ops *header_ops; unsigned int flags; @@ -1964,6 +1971,10 @@ struct net_device { struct mpls_dev __rcu *mpls_ptr; #endif +#ifdef CONFIG_ETHERNET_PACKET_MANGLE + void *phy_ptr; /* PHY device specific data */ +#endif + /* * Cache lines mostly used on receive path (including eth_type_trans()) */ --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2694,6 +2694,10 @@ static inline int pskb_trim(struct sk_bu return (len < skb->len) ? __pskb_trim(skb, len) : 0; } +extern struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev, + unsigned int length, gfp_t gfp); + + /** * pskb_trim_unique - remove end from a paged unique (not cloned) buffer * @skb: buffer to alter @@ -2825,16 +2829,6 @@ static inline struct sk_buff *dev_alloc_ } -static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev, - unsigned int length, gfp_t gfp) -{ - struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp); - - if (NET_IP_ALIGN && skb) - skb_reserve(skb, NET_IP_ALIGN); - return skb; -} - static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev, unsigned int length) { --- a/net/Kconfig +++ b/net/Kconfig @@ -26,6 +26,12 @@ menuconfig NET if NET +config ETHERNET_PACKET_MANGLE + bool + help + This option can be selected by phy drivers that need to mangle + packets going in or out of an ethernet device. + config WANT_COMPAT_NETLINK_MESSAGES bool help --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3221,10 +3221,20 @@ static int xmit_one(struct sk_buff *skb, if (dev_nit_active(dev)) dev_queue_xmit_nit(skb, dev); - len = skb->len; - trace_net_dev_start_xmit(skb, dev); - rc = netdev_start_xmit(skb, dev, txq, more); - trace_net_dev_xmit(skb, rc, dev, len); +#ifdef CONFIG_ETHERNET_PACKET_MANGLE + if (!dev->eth_mangle_tx || + (skb = dev->eth_mangle_tx(dev, skb)) != NULL) +#else + if (1) +#endif + { + len = skb->len; + trace_net_dev_start_xmit(skb, dev); + rc = netdev_start_xmit(skb, dev, txq, more); + trace_net_dev_xmit(skb, rc, dev, len); + } else { + rc = NETDEV_TX_OK; + } return rc; } --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -60,6 +60,7 @@ #include #include #include +#include #include #include @@ -549,6 +550,22 @@ skb_fail: } EXPORT_SYMBOL(__napi_alloc_skb); +struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev, + unsigned int length, gfp_t gfp) +{ + struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp); + +#ifdef CONFIG_ETHERNET_PACKET_MANGLE + if (dev && (dev->priv_flags & IFF_NO_IP_ALIGN)) + return skb; +#endif + + if (NET_IP_ALIGN && skb) + skb_reserve(skb, NET_IP_ALIGN); + return skb; +} +EXPORT_SYMBOL(__netdev_alloc_skb_ip_align); + void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, int size, unsigned int truesize) { --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -171,6 +171,12 @@ __be16 eth_type_trans(struct sk_buff *sk const struct ethhdr *eth; skb->dev = dev; + +#ifdef CONFIG_ETHERNET_PACKET_MANGLE + if (dev->eth_mangle_rx) + dev->eth_mangle_rx(dev, skb); +#endif + skb_reset_mac_header(skb); eth = (struct ethhdr *)skb->data;