The vnet handling code will be reused by tap.
Signed-off-by: Akihiko Odaki akihiko.odaki@daynix.com --- MAINTAINERS | 2 +- drivers/net/Kconfig | 4 ++ drivers/net/Makefile | 1 + drivers/net/tun.c | 174 +--------------------------------------------- drivers/net/tun_vnet.c | 184 +++++++++++++++++++++++++++++++++++++++++++++++++ drivers/net/tun_vnet.h | 25 +++++++ 6 files changed, 217 insertions(+), 173 deletions(-)
diff --git a/MAINTAINERS b/MAINTAINERS index 910305c11e8a882da5b49ce5bd55011b93f28c32..bc32b7e23c79ab80b19c8207f14c5e51a47ec89f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -23902,7 +23902,7 @@ W: http://vtun.sourceforge.net/tun F: Documentation/networking/tuntap.rst F: arch/um/os-Linux/drivers/ F: drivers/net/tap.c -F: drivers/net/tun.c +F: drivers/net/tun*
TURBOCHANNEL SUBSYSTEM M: "Maciej W. Rozycki" macro@orcam.me.uk diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 1fd5acdc73c6af0e1a861867039c3624fc618e25..924bf61f12a49566b26a78f42cea5ca1c48537c5 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -391,10 +391,14 @@ config RIONET_RX_SIZE depends on RIONET default "128"
+config TUN_VNET + tristate + config TUN tristate "Universal TUN/TAP device driver support" depends on INET select CRC32 + select TUN_VNET help TUN/TAP provides packet reception and transmission for user space programs. It can be viewed as a simple Point-to-Point or Ethernet diff --git a/drivers/net/Makefile b/drivers/net/Makefile index 13743d0e83b5fde479e9b30ad736be402d880dee..f6590f2795cf742ab15047d8f1b2d2d8661954a3 100644 --- a/drivers/net/Makefile +++ b/drivers/net/Makefile @@ -29,6 +29,7 @@ obj-y += mdio/ obj-y += pcs/ obj-$(CONFIG_RIONET) += rionet.o obj-$(CONFIG_NET_TEAM) += team/ +obj-$(CONFIG_TUN_VNET) += tun_vnet.o obj-$(CONFIG_TUN) += tun.o obj-$(CONFIG_TAP) += tap.o obj-$(CONFIG_VETH) += veth.o diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 20659a62bb51d2a497a9d3e9e3b3ee7e9fad4f35..21abd3613cacda175d4f469f580a2994b2f836e8 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -83,6 +83,8 @@ #include <linux/uaccess.h> #include <linux/proc_fs.h>
+#include "tun_vnet.h" + static void tun_default_link_ksettings(struct net_device *dev, struct ethtool_link_ksettings *cmd);
@@ -94,9 +96,6 @@ static void tun_default_link_ksettings(struct net_device *dev, * overload it to mean fasync when stored there. */ #define TUN_FASYNC IFF_ATTACH_QUEUE -/* High bits in flags field are unused. */ -#define TUN_VNET_LE 0x80000000 -#define TUN_VNET_BE 0x40000000
#define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \ IFF_MULTI_QUEUE | IFF_NAPI | IFF_NAPI_FRAGS) @@ -298,175 +297,6 @@ static bool tun_napi_frags_enabled(const struct tun_file *tfile) return tfile->napi_frags_enabled; }
-static inline bool tun_legacy_is_little_endian(unsigned int flags) -{ - return !(IS_ENABLED(CONFIG_TUN_VNET_CROSS_LE) && - (flags & TUN_VNET_BE)) && - virtio_legacy_is_little_endian(); -} - -static long tun_get_vnet_be(unsigned int flags, int __user *argp) -{ - int be = !!(flags & TUN_VNET_BE); - - if (!IS_ENABLED(CONFIG_TUN_VNET_CROSS_LE)) - return -EINVAL; - - if (put_user(be, argp)) - return -EFAULT; - - return 0; -} - -static long tun_set_vnet_be(unsigned int *flags, int __user *argp) -{ - int be; - - if (!IS_ENABLED(CONFIG_TUN_VNET_CROSS_LE)) - return -EINVAL; - - if (get_user(be, argp)) - return -EFAULT; - - if (be) - *flags |= TUN_VNET_BE; - else - *flags &= ~TUN_VNET_BE; - - return 0; -} - -static inline bool tun_is_little_endian(unsigned int flags) -{ - return flags & TUN_VNET_LE || tun_legacy_is_little_endian(flags); -} - -static inline u16 tun16_to_cpu(unsigned int flags, __virtio16 val) -{ - return __virtio16_to_cpu(tun_is_little_endian(flags), val); -} - -static inline __virtio16 cpu_to_tun16(unsigned int flags, u16 val) -{ - return __cpu_to_virtio16(tun_is_little_endian(flags), val); -} - -static long tun_vnet_ioctl(int *vnet_hdr_len_sz, unsigned int *flags, - unsigned int cmd, int __user *sp) -{ - int s; - - switch (cmd) { - case TUNGETVNETHDRSZ: - s = *vnet_hdr_len_sz; - if (put_user(s, sp)) - return -EFAULT; - return 0; - - case TUNSETVNETHDRSZ: - if (get_user(s, sp)) - return -EFAULT; - if (s < (int)sizeof(struct virtio_net_hdr)) - return -EINVAL; - - *vnet_hdr_len_sz = s; - return 0; - - case TUNGETVNETLE: - s = !!(*flags & TUN_VNET_LE); - if (put_user(s, sp)) - return -EFAULT; - return 0; - - case TUNSETVNETLE: - if (get_user(s, sp)) - return -EFAULT; - if (s) - *flags |= TUN_VNET_LE; - else - *flags &= ~TUN_VNET_LE; - return 0; - - case TUNGETVNETBE: - return tun_get_vnet_be(*flags, sp); - - case TUNSETVNETBE: - return tun_set_vnet_be(flags, sp); - - default: - return -EINVAL; - } -} - -static int tun_vnet_hdr_get(int sz, unsigned int flags, struct iov_iter *from, - struct virtio_net_hdr *hdr) -{ - if (iov_iter_count(from) < sz) - return -EINVAL; - - if (!copy_from_iter_full(hdr, sizeof(*hdr), from)) - return -EFAULT; - - if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && - tun16_to_cpu(flags, hdr->csum_start) + tun16_to_cpu(flags, hdr->csum_offset) + 2 > tun16_to_cpu(flags, hdr->hdr_len)) - hdr->hdr_len = cpu_to_tun16(flags, tun16_to_cpu(flags, hdr->csum_start) + tun16_to_cpu(flags, hdr->csum_offset) + 2); - - if (tun16_to_cpu(flags, hdr->hdr_len) > iov_iter_count(from)) - return -EINVAL; - - iov_iter_advance(from, sz - sizeof(*hdr)); - - return tun16_to_cpu(flags, hdr->hdr_len); -} - -static int tun_vnet_hdr_put(int sz, struct iov_iter *iter, - const struct virtio_net_hdr *hdr) -{ - if (unlikely(iov_iter_count(iter) < sz)) - return -EINVAL; - - if (unlikely(copy_to_iter(hdr, sizeof(*hdr), iter) != sizeof(*hdr))) - return -EFAULT; - - iov_iter_advance(iter, sz - sizeof(*hdr)); - - return 0; -} - -static int tun_vnet_hdr_to_skb(unsigned int flags, struct sk_buff *skb, - const struct virtio_net_hdr *hdr) -{ - return virtio_net_hdr_to_skb(skb, hdr, tun_is_little_endian(flags)); -} - -static int tun_vnet_hdr_from_skb(unsigned int flags, - const struct net_device *dev, - const struct sk_buff *skb, - struct virtio_net_hdr *hdr) -{ - int vlan_hlen = skb_vlan_tag_present(skb) ? VLAN_HLEN : 0; - - if (virtio_net_hdr_from_skb(skb, hdr, - tun_is_little_endian(flags), true, - vlan_hlen)) { - struct skb_shared_info *sinfo = skb_shinfo(skb); - - if (net_ratelimit()) { - netdev_err(dev, "unexpected GSO type: 0x%x, gso_size %d, hdr_len %d\n", - sinfo->gso_type, tun16_to_cpu(flags, hdr->gso_size), - tun16_to_cpu(flags, hdr->hdr_len)); - print_hex_dump(KERN_ERR, "tun: ", - DUMP_PREFIX_NONE, - 16, 1, skb->head, - min(tun16_to_cpu(flags, hdr->hdr_len), 64), true); - } - WARN_ON_ONCE(1); - return -EINVAL; - } - - return 0; -} - static inline u32 tun_hashfn(u32 rxhash) { return rxhash & TUN_MASK_FLOW_ENTRIES; diff --git a/drivers/net/tun_vnet.c b/drivers/net/tun_vnet.c new file mode 100644 index 0000000000000000000000000000000000000000..5e5dd9c6aa38323914f714ba82d9848c29fba484 --- /dev/null +++ b/drivers/net/tun_vnet.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include "tun_vnet.h" + +/* High bits in flags field are unused. */ +#define TUN_VNET_LE 0x80000000 +#define TUN_VNET_BE 0x40000000 + +static inline bool tun_legacy_is_little_endian(unsigned int flags) +{ + return !(IS_ENABLED(CONFIG_TUN_VNET_CROSS_LE) && + (flags & TUN_VNET_BE)) && + virtio_legacy_is_little_endian(); +} + +static long tun_get_vnet_be(unsigned int flags, int __user *argp) +{ + int be = !!(flags & TUN_VNET_BE); + + if (!IS_ENABLED(CONFIG_TUN_VNET_CROSS_LE)) + return -EINVAL; + + if (put_user(be, argp)) + return -EFAULT; + + return 0; +} + +static long tun_set_vnet_be(unsigned int *flags, int __user *argp) +{ + int be; + + if (!IS_ENABLED(CONFIG_TUN_VNET_CROSS_LE)) + return -EINVAL; + + if (get_user(be, argp)) + return -EFAULT; + + if (be) + *flags |= TUN_VNET_BE; + else + *flags &= ~TUN_VNET_BE; + + return 0; +} + +static inline bool tun_is_little_endian(unsigned int flags) +{ + return flags & TUN_VNET_LE || tun_legacy_is_little_endian(flags); +} + +static inline u16 tun16_to_cpu(unsigned int flags, __virtio16 val) +{ + return __virtio16_to_cpu(tun_is_little_endian(flags), val); +} + +static inline __virtio16 cpu_to_tun16(unsigned int flags, u16 val) +{ + return __cpu_to_virtio16(tun_is_little_endian(flags), val); +} + +long tun_vnet_ioctl(int *vnet_hdr_len_sz, unsigned int *flags, + unsigned int cmd, int __user *sp) +{ + int s; + + switch (cmd) { + case TUNGETVNETHDRSZ: + s = *vnet_hdr_len_sz; + if (put_user(s, sp)) + return -EFAULT; + return 0; + + case TUNSETVNETHDRSZ: + if (get_user(s, sp)) + return -EFAULT; + if (s < (int)sizeof(struct virtio_net_hdr)) + return -EINVAL; + + *vnet_hdr_len_sz = s; + return 0; + + case TUNGETVNETLE: + s = !!(*flags & TUN_VNET_LE); + if (put_user(s, sp)) + return -EFAULT; + return 0; + + case TUNSETVNETLE: + if (get_user(s, sp)) + return -EFAULT; + if (s) + *flags |= TUN_VNET_LE; + else + *flags &= ~TUN_VNET_LE; + return 0; + + case TUNGETVNETBE: + return tun_get_vnet_be(*flags, sp); + + case TUNSETVNETBE: + return tun_set_vnet_be(flags, sp); + + default: + return -EINVAL; + } +} +EXPORT_SYMBOL_GPL(tun_vnet_ioctl); + +int tun_vnet_hdr_get(int sz, unsigned int flags, struct iov_iter *from, + struct virtio_net_hdr *hdr) +{ + if (iov_iter_count(from) < sz) + return -EINVAL; + + if (!copy_from_iter_full(hdr, sizeof(*hdr), from)) + return -EFAULT; + + if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && + tun16_to_cpu(flags, hdr->csum_start) + tun16_to_cpu(flags, hdr->csum_offset) + 2 > tun16_to_cpu(flags, hdr->hdr_len)) + hdr->hdr_len = cpu_to_tun16(flags, tun16_to_cpu(flags, hdr->csum_start) + tun16_to_cpu(flags, hdr->csum_offset) + 2); + + if (tun16_to_cpu(flags, hdr->hdr_len) > iov_iter_count(from)) + return -EINVAL; + + iov_iter_advance(from, sz - sizeof(*hdr)); + + return tun16_to_cpu(flags, hdr->hdr_len); +} +EXPORT_SYMBOL_GPL(tun_vnet_hdr_get); + +int tun_vnet_hdr_put(int sz, struct iov_iter *iter, + const struct virtio_net_hdr *hdr) +{ + if (unlikely(iov_iter_count(iter) < sz)) + return -EINVAL; + + if (unlikely(copy_to_iter(hdr, sizeof(*hdr), iter) != sizeof(*hdr))) + return -EFAULT; + + iov_iter_advance(iter, sz - sizeof(*hdr)); + + return 0; +} +EXPORT_SYMBOL_GPL(tun_vnet_hdr_put); + +int tun_vnet_hdr_to_skb(unsigned int flags, struct sk_buff *skb, + const struct virtio_net_hdr *hdr) +{ + return virtio_net_hdr_to_skb(skb, hdr, tun_is_little_endian(flags)); +} +EXPORT_SYMBOL_GPL(tun_vnet_hdr_to_skb); + +int tun_vnet_hdr_from_skb(unsigned int flags, + const struct net_device *dev, + const struct sk_buff *skb, + struct virtio_net_hdr *hdr) +{ + int vlan_hlen = skb_vlan_tag_present(skb) ? VLAN_HLEN : 0; + + if (virtio_net_hdr_from_skb(skb, hdr, + tun_is_little_endian(flags), true, + vlan_hlen)) { + struct skb_shared_info *sinfo = skb_shinfo(skb); + + if (net_ratelimit()) { + netdev_err(dev, "unexpected GSO type: 0x%x, gso_size %d, hdr_len %d\n", + sinfo->gso_type, tun16_to_cpu(flags, hdr->gso_size), + tun16_to_cpu(flags, hdr->hdr_len)); + print_hex_dump(KERN_ERR, "tun: ", + DUMP_PREFIX_NONE, + 16, 1, skb->head, + min(tun16_to_cpu(flags, hdr->hdr_len), 64), true); + } + WARN_ON_ONCE(1); + return -EINVAL; + } + + return 0; +} +EXPORT_SYMBOL_GPL(tun_vnet_hdr_from_skb); + +MODULE_DESCRIPTION("Common library for drivers implementing TUN/TAP's virtio-related features"); +MODULE_AUTHOR("Max Krasnyansky maxk@qualcomm.com"); +MODULE_LICENSE("GPL"); diff --git a/drivers/net/tun_vnet.h b/drivers/net/tun_vnet.h new file mode 100644 index 0000000000000000000000000000000000000000..a8d6e474933399d9c6161bef31e385f5c538da1c --- /dev/null +++ b/drivers/net/tun_vnet.h @@ -0,0 +1,25 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef TUN_VNET_H +#define TUN_VNET_H + +#include <linux/if_tun.h> +#include <linux/virtio_net.h> + +long tun_vnet_ioctl(int *sz, unsigned int *flags, + unsigned int cmd, int __user *sp); + +int tun_vnet_hdr_get(int sz, unsigned int flags, struct iov_iter *from, + struct virtio_net_hdr *hdr); + +int tun_vnet_hdr_put(int sz, struct iov_iter *iter, + const struct virtio_net_hdr *hdr); + +int tun_vnet_hdr_to_skb(unsigned int flags, struct sk_buff *skb, + const struct virtio_net_hdr *hdr); + +int tun_vnet_hdr_from_skb(unsigned int flags, + const struct net_device *dev, + const struct sk_buff *skb, + struct virtio_net_hdr *hdr); + +#endif /* TUN_VNET_H */