kernel/linux.git/net/ipv6/exthdrs.c, branch v5.16

ipv6: ioam: Distinguish input and output for hop-limit

2021-10-04T11:53:35+00:00

This patch anticipates the support for the IOAM insertion inside in-transit packets, by making a difference between input and output in order to determine the right value for its hop-limit (inherited from the IPv6 hop-limit). Input case: happens before ip6_forward, the IPv6 hop-limit is not decremented yet -> decrement the IOAM hop-limit to reflect the new hop inside the trace. Output case: happens after ip6_forward, the IPv6 hop-limit has already been decremented -> keep the same value for the IOAM hop-limit. Signed-off-by: Justin Iurman Signed-off-by: David S. Miller

ipv6: exthdrs: get rid of indirect calls in ip6_parse_tlv()

2021-08-04T09:34:40+00:00

As presented last month in our "BIG TCP" talk at netdev 0x15, we plan using IPv6 jumbograms. One of the minor problem we talked about is the fact that ip6_parse_tlv() is currently using tables to list known tlvs, thus using potentially expensive indirect calls. While we could mitigate this cost using macros from indirect_call_wrapper.h, we also can get rid of the tables and let the compiler emit optimized code. Signed-off-by: Eric Dumazet Cc: Justin Iurman Cc: Coco Li Signed-off-by: David S. Miller

ipv6: ioam: Data plane support for Pre-allocated Trace

2021-07-21T15:14:33+00:00

Implement support for processing the IOAM Pre-allocated Trace with IPv6, see [1] and [2]. Introduce a new IPv6 Hop-by-Hop TLV option, see IANA [3]. A new per-interface sysctl is introduced. The value is a boolean to accept (=1) or ignore (=0, by default) IPv6 IOAM options on ingress for an interface: - net.ipv6.conf.XXX.ioam6_enabled Two other sysctls are introduced to define IOAM IDs, represented by an integer. They are respectively per-namespace and per-interface: - net.ipv6.ioam6_id - net.ipv6.conf.XXX.ioam6_id The value of the first one represents the IOAM ID of the node itself (u32; max and default value = U32_MAX>>8, due to hop limit concatenation) while the other represents the IOAM ID of an interface (u16; max and default value = U16_MAX). Each "ioam6_id" sysctl has a "_wide" equivalent: - net.ipv6.ioam6_id_wide - net.ipv6.conf.XXX.ioam6_id_wide The value of the first one represents the wide IOAM ID of the node itself (u64; max and default value = U64_MAX>>8, due to hop limit concatenation) while the other represents the wide IOAM ID of an interface (u32; max and default value = U32_MAX). The use of short and wide equivalents is not exclusive, a deployment could choose to leverage both. For example, net.ipv6.conf.XXX.ioam6_id (short format) could be an identifier for a physical interface, whereas net.ipv6.conf.XXX.ioam6_id_wide (wide format) could be an identifier for a logical sub-interface. Documentation about new sysctls is provided at the end of this patchset. Two relativistic hash tables are used: one for IOAM namespaces, the other for IOAM schemas. A namespace can only have a single active schema and a schema can only be attached to a single namespace (1:1 relationship). [1] https://tools.ietf.org/html/draft-ietf-ippm-ioam-ipv6-options [2] https://tools.ietf.org/html/draft-ietf-ippm-ioam-data [3] https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#ipv6-parameters-2 Signed-off-by: Justin Iurman Signed-off-by: David S. Miller

ipv6: fix out-of-bound access in ip6_parse_tlv()

2021-06-24T19:42:57+00:00

First problem is that optlen is fetched without checking there is more than one byte to parse. Fix this by taking care of IPV6_TLV_PAD1 before fetching optlen (under appropriate sanity checks against len) Second problem is that IPV6_TLV_PADN checks of zero padding are performed before the check of remaining length. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Fixes: c1412fce7ecc ("net/ipv6/exthdrs.c: Strict PadN option checking") Signed-off-by: Eric Dumazet Cc: Paolo Abeni Cc: Tom Herbert Signed-off-by: David S. Miller

ipv6: exthdrs: do not blindly use init_net

2021-06-23T20:53:38+00:00

I see no reason why max_dst_opts_cnt and max_hbh_opts_cnt are fetched from the initial net namespace. The other sysctls (max_dst_opts_len & max_hbh_opts_len) are in fact already using the current ns. Note: it is not clear why ipv6_destopt_rcv() use two ways to get to the netns : 1) dev_net(dst->dev) Originally used to increment IPSTATS_MIB_INHDRERRORS 2) dev_net(skb->dev) Tom used this variant in his patch. Maybe this calls to use ipv6_skb_net() instead ? Fixes: 47d3d7ac656a ("ipv6: Implement limits on Hop-by-Hop and Destination options") Signed-off-by: Eric Dumazet Cc: Tom Herbert Cc: Coco Li Signed-off-by: David S. Miller

seg6: add support for IPv4 decapsulation in ipv6_srh_rcv()

2021-03-12T00:09:21+00:00

As specified in IETF RFC 8754, section 4.3.1.2, if the upper layer header is IPv4 or IPv6, perform IPv6 decapsulation and resubmit the decapsulated packet to the IPv4 or IPv6 module. Only IPv6 decapsulation was implemented. This patch adds support for IPv4 decapsulation. Link: https://tools.ietf.org/html/rfc8754#section-4.3.1.2 Signed-off-by: Julien Massonneau Signed-off-by: David S. Miller

ipv6: remove unused function ipv6_skb_idev()

2020-11-14T20:00:27+00:00

Commit bdb7cc643fc9 ("ipv6: Count interface receive statistics on the ingress netdev") removed all callees for ipv6_skb_idev(). Hence, since then, ipv6_skb_idev() is unused and make CC=clang W=1 warns: net/ipv6/exthdrs.c:909:33: warning: unused function 'ipv6_skb_idev' [-Wunused-function] So, remove this unused function and a -Wunused-function warning. Signed-off-by: Lukas Bulwahn Reviewed-by: Nathan Chancellor Link: https://lore.kernel.org/r/20201113135012.32499-1-lukas.bulwahn@gmail.com Signed-off-by: Jakub Kicinski

net: ipv6: kerneldoc fixes

2020-07-14T00:20:39+00:00

Simple fixes which require no deep knowledge of the code. Cc: Alexey Kuznetsov Cc: Hideaki YOSHIFUJI Signed-off-by: Andrew Lunn Signed-off-by: David S. Miller

net: ipv6: Use struct_size() helper and kcalloc()

2020-06-24T03:27:09+00:00

Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes. Also, remove unnecessary function ipv6_rpl_srh_alloc_size() and replace kzalloc() with kcalloc(), which has a 2-factor argument form for multiplication. This code was detected with the help of Coccinelle and, audited and fixed manually. Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller

net: ipv6: add support for rpl sr exthdr

2020-03-30T05:30:57+00:00

This patch adds rpl source routing receive handling. Everything works only if sysconf "rpl_seg_enabled" and source routing is enabled. Mostly the same behaviour as IPv6 segmentation routing. To handle compression and uncompression a rpl.c file is created which contains the necessary functionality. The receive handling will also care about IPv6 encapsulated so far it's specified as possible nexthdr in RFC 6554. Signed-off-by: Alexander Aring Signed-off-by: David S. Miller