| Message ID | 1389261768-30606-2-git-send-email-paul.durrant@citrix.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
> -----Original Message----- > From: Paul Durrant [mailto:paul.durrant@citrix.com] > Sent: 09 January 2014 10:03 > To: netdev@vger.kernel.org; xen-devel@lists.xen.org > Cc: Paul Durrant; David Miller; Eric Dumazet; Veaceslav Falico; Alexander > Duyck; Nicolas Dichtel > Subject: [PATCH net-next v2 1/3] net: add skb_checksum_setup > > This patch adds a function to set up the partial checksum offset for IP > packets (and optionally re-calculate the pseudo-header checksum) into the > core network code. > The implementation was previously private and duplicated between xen- > netback > and xen-netfront, however it is not xen-specific and is potentially useful > to any network driver. > > Signed-off-by: Paul Durrant <paul.durrant@citrix.com> > Cc: David Miller <davem@davemloft.net> > Cc: Eric Dumazet <edumazet@google.com> > Cc: Veaceslav Falico <vfalico@redhat.com> > Cc: Alexander Duyck <alexander.h.duyck@intel.com> > Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> Ping? Paul > --- > include/linux/skbuff.h | 2 + > net/core/skbuff.c | 273 > ++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 275 insertions(+) > > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h > index d97f2d0..48b7605 100644 > --- a/include/linux/skbuff.h > +++ b/include/linux/skbuff.h > @@ -2893,6 +2893,8 @@ static inline void skb_checksum_none_assert(const > struct sk_buff *skb) > > bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off); > > +int skb_checksum_setup(struct sk_buff *skb, bool recalculate); > + > u32 __skb_get_poff(const struct sk_buff *skb); > > /** > diff --git a/net/core/skbuff.c b/net/core/skbuff.c > index 1d641e7..15057d2 100644 > --- a/net/core/skbuff.c > +++ b/net/core/skbuff.c > @@ -65,6 +65,7 @@ > #include <net/dst.h> > #include <net/sock.h> > #include <net/checksum.h> > +#include <net/ip6_checksum.h> > #include <net/xfrm.h> > > #include <asm/uaccess.h> > @@ -3549,6 +3550,278 @@ bool skb_partial_csum_set(struct sk_buff *skb, > u16 start, u16 off) > } > EXPORT_SYMBOL_GPL(skb_partial_csum_set); > > +static int skb_maybe_pull_tail(struct sk_buff *skb, unsigned int len, > + unsigned int max) > +{ > + if (skb_headlen(skb) >= len) > + return 0; > + > + /* If we need to pullup then pullup to the max, so we > + * won't need to do it again. > + */ > + if (max > skb->len) > + max = skb->len; > + > + if (__pskb_pull_tail(skb, max - skb_headlen(skb)) == NULL) > + return -ENOMEM; > + > + if (skb_headlen(skb) < len) > + return -EPROTO; > + > + return 0; > +} > + > +/* This value should be large enough to cover a tagged ethernet header > plus > + * maximally sized IP and TCP or UDP headers. > + */ > +#define MAX_IP_HDR_LEN 128 > + > +static int skb_checksum_setup_ip(struct sk_buff *skb, bool recalculate) > +{ > + unsigned int off; > + bool fragment; > + int err; > + > + fragment = false; > + > + err = skb_maybe_pull_tail(skb, > + sizeof(struct iphdr), > + MAX_IP_HDR_LEN); > + if (err < 0) > + goto out; > + > + if (ip_hdr(skb)->frag_off & htons(IP_OFFSET | IP_MF)) > + fragment = true; > + > + off = ip_hdrlen(skb); > + > + err = -EPROTO; > + > + if (fragment) > + goto out; > + > + switch (ip_hdr(skb)->protocol) { > + case IPPROTO_TCP: > + err = skb_maybe_pull_tail(skb, > + off + sizeof(struct tcphdr), > + MAX_IP_HDR_LEN); > + if (err < 0) > + goto out; > + > + if (!skb_partial_csum_set(skb, off, > + offsetof(struct tcphdr, check))) { > + err = -EPROTO; > + goto out; > + } > + > + if (recalculate) > + tcp_hdr(skb)->check = > + ~csum_tcpudp_magic(ip_hdr(skb)->saddr, > + ip_hdr(skb)->daddr, > + skb->len - off, > + IPPROTO_TCP, 0); > + break; > + case IPPROTO_UDP: > + err = skb_maybe_pull_tail(skb, > + off + sizeof(struct udphdr), > + MAX_IP_HDR_LEN); > + if (err < 0) > + goto out; > + > + if (!skb_partial_csum_set(skb, off, > + offsetof(struct udphdr, check))) { > + err = -EPROTO; > + goto out; > + } > + > + if (recalculate) > + udp_hdr(skb)->check = > + ~csum_tcpudp_magic(ip_hdr(skb)->saddr, > + ip_hdr(skb)->daddr, > + skb->len - off, > + IPPROTO_UDP, 0); > + break; > + default: > + goto out; > + } > + > + err = 0; > + > +out: > + return err; > +} > + > +/* This value should be large enough to cover a tagged ethernet header > plus > + * an IPv6 header, all options, and a maximal TCP or UDP header. > + */ > +#define MAX_IPV6_HDR_LEN 256 > + > +#define OPT_HDR(type, skb, off) \ > + (type *)(skb_network_header(skb) + (off)) > + > +static int skb_checksum_setup_ipv6(struct sk_buff *skb, bool recalculate) > +{ > + int err; > + u8 nexthdr; > + unsigned int off; > + unsigned int len; > + bool fragment; > + bool done; > + > + fragment = false; > + done = false; > + > + off = sizeof(struct ipv6hdr); > + > + err = skb_maybe_pull_tail(skb, off, MAX_IPV6_HDR_LEN); > + if (err < 0) > + goto out; > + > + nexthdr = ipv6_hdr(skb)->nexthdr; > + > + len = sizeof(struct ipv6hdr) + ntohs(ipv6_hdr(skb)->payload_len); > + while (off <= len && !done) { > + switch (nexthdr) { > + case IPPROTO_DSTOPTS: > + case IPPROTO_HOPOPTS: > + case IPPROTO_ROUTING: { > + struct ipv6_opt_hdr *hp; > + > + err = skb_maybe_pull_tail(skb, > + off + > + sizeof(struct ipv6_opt_hdr), > + MAX_IPV6_HDR_LEN); > + if (err < 0) > + goto out; > + > + hp = OPT_HDR(struct ipv6_opt_hdr, skb, off); > + nexthdr = hp->nexthdr; > + off += ipv6_optlen(hp); > + break; > + } > + case IPPROTO_AH: { > + struct ip_auth_hdr *hp; > + > + err = skb_maybe_pull_tail(skb, > + off + > + sizeof(struct ip_auth_hdr), > + MAX_IPV6_HDR_LEN); > + if (err < 0) > + goto out; > + > + hp = OPT_HDR(struct ip_auth_hdr, skb, off); > + nexthdr = hp->nexthdr; > + off += ipv6_authlen(hp); > + break; > + } > + case IPPROTO_FRAGMENT: { > + struct frag_hdr *hp; > + > + err = skb_maybe_pull_tail(skb, > + off + > + sizeof(struct frag_hdr), > + MAX_IPV6_HDR_LEN); > + if (err < 0) > + goto out; > + > + hp = OPT_HDR(struct frag_hdr, skb, off); > + > + if (hp->frag_off & htons(IP6_OFFSET | IP6_MF)) > + fragment = true; > + > + nexthdr = hp->nexthdr; > + off += sizeof(struct frag_hdr); > + break; > + } > + default: > + done = true; > + break; > + } > + } > + > + err = -EPROTO; > + > + if (!done || fragment) > + goto out; > + > + switch (nexthdr) { > + case IPPROTO_TCP: > + err = skb_maybe_pull_tail(skb, > + off + sizeof(struct tcphdr), > + MAX_IPV6_HDR_LEN); > + if (err < 0) > + goto out; > + > + if (!skb_partial_csum_set(skb, off, > + offsetof(struct tcphdr, check))) { > + err = -EPROTO; > + goto out; > + } > + > + if (recalculate) > + tcp_hdr(skb)->check = > + ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, > + &ipv6_hdr(skb)->daddr, > + skb->len - off, > + IPPROTO_TCP, 0); > + break; > + case IPPROTO_UDP: > + err = skb_maybe_pull_tail(skb, > + off + sizeof(struct udphdr), > + MAX_IPV6_HDR_LEN); > + if (err < 0) > + goto out; > + > + if (!skb_partial_csum_set(skb, off, > + offsetof(struct udphdr, check))) { > + err = -EPROTO; > + goto out; > + } > + > + if (recalculate) > + udp_hdr(skb)->check = > + ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, > + &ipv6_hdr(skb)->daddr, > + skb->len - off, > + IPPROTO_UDP, 0); > + break; > + default: > + goto out; > + } > + > + err = 0; > + > +out: > + return err; > +} > + > +/** > + * skb_checksum_setup - set up partial checksum offset > + * @skb: the skb to set up > + * @recalculate: if true the pseudo-header checksum will be recalculated > + */ > +int skb_checksum_setup(struct sk_buff *skb, bool recalculate) > +{ > + int err; > + > + switch (skb->protocol) { > + case htons(ETH_P_IP): > + err = skb_checksum_setup_ip(skb, recalculate); > + break; > + > + case htons(ETH_P_IPV6): > + err = skb_checksum_setup_ipv6(skb, recalculate); > + break; > + > + default: > + err = -EPROTO; > + break; > + } > + > + return err; > +} > +EXPORT_SYMBOL(skb_checksum_setup); > + > void __skb_warn_lro_forwarding(const struct sk_buff *skb) > { > net_warn_ratelimited("%s: received packets cannot be forwarded > while LRO is enabled\n", > -- > 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Le 13/01/2014 12:26, Paul Durrant a écrit : >> -----Original Message----- >> From: Paul Durrant [mailto:paul.durrant@citrix.com] >> Sent: 09 January 2014 10:03 >> To: netdev@vger.kernel.org; xen-devel@lists.xen.org >> Cc: Paul Durrant; David Miller; Eric Dumazet; Veaceslav Falico; Alexander >> Duyck; Nicolas Dichtel >> Subject: [PATCH net-next v2 1/3] net: add skb_checksum_setup >> >> This patch adds a function to set up the partial checksum offset for IP >> packets (and optionally re-calculate the pseudo-header checksum) into the >> core network code. >> The implementation was previously private and duplicated between xen- >> netback >> and xen-netfront, however it is not xen-specific and is potentially useful >> to any network driver. >> >> Signed-off-by: Paul Durrant <paul.durrant@citrix.com> >> Cc: David Miller <davem@davemloft.net> >> Cc: Eric Dumazet <edumazet@google.com> >> Cc: Veaceslav Falico <vfalico@redhat.com> >> Cc: Alexander Duyck <alexander.h.duyck@intel.com> >> Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> > > Ping? Your patch is under review by David (see http://patchwork.ozlabs.org/patch/308539/), please be patient ;-) Nicolas -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index d97f2d0..48b7605 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2893,6 +2893,8 @@ static inline void skb_checksum_none_assert(const struct sk_buff *skb) bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off); +int skb_checksum_setup(struct sk_buff *skb, bool recalculate); + u32 __skb_get_poff(const struct sk_buff *skb); /** diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 1d641e7..15057d2 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -65,6 +65,7 @@ #include <net/dst.h> #include <net/sock.h> #include <net/checksum.h> +#include <net/ip6_checksum.h> #include <net/xfrm.h> #include <asm/uaccess.h> @@ -3549,6 +3550,278 @@ bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off) } EXPORT_SYMBOL_GPL(skb_partial_csum_set); +static int skb_maybe_pull_tail(struct sk_buff *skb, unsigned int len, + unsigned int max) +{ + if (skb_headlen(skb) >= len) + return 0; + + /* If we need to pullup then pullup to the max, so we + * won't need to do it again. + */ + if (max > skb->len) + max = skb->len; + + if (__pskb_pull_tail(skb, max - skb_headlen(skb)) == NULL) + return -ENOMEM; + + if (skb_headlen(skb) < len) + return -EPROTO; + + return 0; +} + +/* This value should be large enough to cover a tagged ethernet header plus + * maximally sized IP and TCP or UDP headers. + */ +#define MAX_IP_HDR_LEN 128 + +static int skb_checksum_setup_ip(struct sk_buff *skb, bool recalculate) +{ + unsigned int off; + bool fragment; + int err; + + fragment = false; + + err = skb_maybe_pull_tail(skb, + sizeof(struct iphdr), + MAX_IP_HDR_LEN); + if (err < 0) + goto out; + + if (ip_hdr(skb)->frag_off & htons(IP_OFFSET | IP_MF)) + fragment = true; + + off = ip_hdrlen(skb); + + err = -EPROTO; + + if (fragment) + goto out; + + switch (ip_hdr(skb)->protocol) { + case IPPROTO_TCP: + err = skb_maybe_pull_tail(skb, + off + sizeof(struct tcphdr), + MAX_IP_HDR_LEN); + if (err < 0) + goto out; + + if (!skb_partial_csum_set(skb, off, + offsetof(struct tcphdr, check))) { + err = -EPROTO; + goto out; + } + + if (recalculate) + tcp_hdr(skb)->check = + ~csum_tcpudp_magic(ip_hdr(skb)->saddr, + ip_hdr(skb)->daddr, + skb->len - off, + IPPROTO_TCP, 0); + break; + case IPPROTO_UDP: + err = skb_maybe_pull_tail(skb, + off + sizeof(struct udphdr), + MAX_IP_HDR_LEN); + if (err < 0) + goto out; + + if (!skb_partial_csum_set(skb, off, + offsetof(struct udphdr, check))) { + err = -EPROTO; + goto out; + } + + if (recalculate) + udp_hdr(skb)->check = + ~csum_tcpudp_magic(ip_hdr(skb)->saddr, + ip_hdr(skb)->daddr, + skb->len - off, + IPPROTO_UDP, 0); + break; + default: + goto out; + } + + err = 0; + +out: + return err; +} + +/* This value should be large enough to cover a tagged ethernet header plus + * an IPv6 header, all options, and a maximal TCP or UDP header. + */ +#define MAX_IPV6_HDR_LEN 256 + +#define OPT_HDR(type, skb, off) \ + (type *)(skb_network_header(skb) + (off)) + +static int skb_checksum_setup_ipv6(struct sk_buff *skb, bool recalculate) +{ + int err; + u8 nexthdr; + unsigned int off; + unsigned int len; + bool fragment; + bool done; + + fragment = false; + done = false; + + off = sizeof(struct ipv6hdr); + + err = skb_maybe_pull_tail(skb, off, MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + nexthdr = ipv6_hdr(skb)->nexthdr; + + len = sizeof(struct ipv6hdr) + ntohs(ipv6_hdr(skb)->payload_len); + while (off <= len && !done) { + switch (nexthdr) { + case IPPROTO_DSTOPTS: + case IPPROTO_HOPOPTS: + case IPPROTO_ROUTING: { + struct ipv6_opt_hdr *hp; + + err = skb_maybe_pull_tail(skb, + off + + sizeof(struct ipv6_opt_hdr), + MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + hp = OPT_HDR(struct ipv6_opt_hdr, skb, off); + nexthdr = hp->nexthdr; + off += ipv6_optlen(hp); + break; + } + case IPPROTO_AH: { + struct ip_auth_hdr *hp; + + err = skb_maybe_pull_tail(skb, + off + + sizeof(struct ip_auth_hdr), + MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + hp = OPT_HDR(struct ip_auth_hdr, skb, off); + nexthdr = hp->nexthdr; + off += ipv6_authlen(hp); + break; + } + case IPPROTO_FRAGMENT: { + struct frag_hdr *hp; + + err = skb_maybe_pull_tail(skb, + off + + sizeof(struct frag_hdr), + MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + hp = OPT_HDR(struct frag_hdr, skb, off); + + if (hp->frag_off & htons(IP6_OFFSET | IP6_MF)) + fragment = true; + + nexthdr = hp->nexthdr; + off += sizeof(struct frag_hdr); + break; + } + default: + done = true; + break; + } + } + + err = -EPROTO; + + if (!done || fragment) + goto out; + + switch (nexthdr) { + case IPPROTO_TCP: + err = skb_maybe_pull_tail(skb, + off + sizeof(struct tcphdr), + MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + if (!skb_partial_csum_set(skb, off, + offsetof(struct tcphdr, check))) { + err = -EPROTO; + goto out; + } + + if (recalculate) + tcp_hdr(skb)->check = + ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr, + skb->len - off, + IPPROTO_TCP, 0); + break; + case IPPROTO_UDP: + err = skb_maybe_pull_tail(skb, + off + sizeof(struct udphdr), + MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + if (!skb_partial_csum_set(skb, off, + offsetof(struct udphdr, check))) { + err = -EPROTO; + goto out; + } + + if (recalculate) + udp_hdr(skb)->check = + ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr, + skb->len - off, + IPPROTO_UDP, 0); + break; + default: + goto out; + } + + err = 0; + +out: + return err; +} + +/** + * skb_checksum_setup - set up partial checksum offset + * @skb: the skb to set up + * @recalculate: if true the pseudo-header checksum will be recalculated + */ +int skb_checksum_setup(struct sk_buff *skb, bool recalculate) +{ + int err; + + switch (skb->protocol) { + case htons(ETH_P_IP): + err = skb_checksum_setup_ip(skb, recalculate); + break; + + case htons(ETH_P_IPV6): + err = skb_checksum_setup_ipv6(skb, recalculate); + break; + + default: + err = -EPROTO; + break; + } + + return err; +} +EXPORT_SYMBOL(skb_checksum_setup); + void __skb_warn_lro_forwarding(const struct sk_buff *skb) { net_warn_ratelimited("%s: received packets cannot be forwarded while LRO is enabled\n",
This patch adds a function to set up the partial checksum offset for IP packets (and optionally re-calculate the pseudo-header checksum) into the core network code. The implementation was previously private and duplicated between xen-netback and xen-netfront, however it is not xen-specific and is potentially useful to any network driver. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Veaceslav Falico <vfalico@redhat.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> --- include/linux/skbuff.h | 2 + net/core/skbuff.c | 273 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 275 insertions(+)