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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /net/ipv6/ah6.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to 'net/ipv6/ah6.c')
-rw-r--r-- | net/ipv6/ah6.c | 807 |
1 files changed, 807 insertions, 0 deletions
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c new file mode 100644 index 000000000..01005035a --- /dev/null +++ b/net/ipv6/ah6.c @@ -0,0 +1,807 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C)2002 USAGI/WIDE Project + * + * Authors + * + * Mitsuru KANDA @USAGI : IPv6 Support + * Kazunori MIYAZAWA @USAGI : + * Kunihiro Ishiguro <kunihiro@ipinfusion.com> + * + * This file is derived from net/ipv4/ah.c. + */ + +#define pr_fmt(fmt) "IPv6: " fmt + +#include <crypto/algapi.h> +#include <crypto/hash.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <net/ip.h> +#include <net/ah.h> +#include <linux/crypto.h> +#include <linux/pfkeyv2.h> +#include <linux/string.h> +#include <linux/scatterlist.h> +#include <net/ip6_route.h> +#include <net/icmp.h> +#include <net/ipv6.h> +#include <net/protocol.h> +#include <net/xfrm.h> + +#define IPV6HDR_BASELEN 8 + +struct tmp_ext { +#if IS_ENABLED(CONFIG_IPV6_MIP6) + struct in6_addr saddr; +#endif + struct in6_addr daddr; + char hdrs[]; +}; + +struct ah_skb_cb { + struct xfrm_skb_cb xfrm; + void *tmp; +}; + +#define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) + +static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, + unsigned int size) +{ + unsigned int len; + + len = size + crypto_ahash_digestsize(ahash) + + (crypto_ahash_alignmask(ahash) & + ~(crypto_tfm_ctx_alignment() - 1)); + + len = ALIGN(len, crypto_tfm_ctx_alignment()); + + len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); + len = ALIGN(len, __alignof__(struct scatterlist)); + + len += sizeof(struct scatterlist) * nfrags; + + return kmalloc(len, GFP_ATOMIC); +} + +static inline struct tmp_ext *ah_tmp_ext(void *base) +{ + return base + IPV6HDR_BASELEN; +} + +static inline u8 *ah_tmp_auth(u8 *tmp, unsigned int offset) +{ + return tmp + offset; +} + +static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, + unsigned int offset) +{ + return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); +} + +static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, + u8 *icv) +{ + struct ahash_request *req; + + req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), + crypto_tfm_ctx_alignment()); + + ahash_request_set_tfm(req, ahash); + + return req; +} + +static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, + struct ahash_request *req) +{ + return (void *)ALIGN((unsigned long)(req + 1) + + crypto_ahash_reqsize(ahash), + __alignof__(struct scatterlist)); +} + +static bool zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr) +{ + u8 *opt = (u8 *)opthdr; + int len = ipv6_optlen(opthdr); + int off = 0; + int optlen = 0; + + off += 2; + len -= 2; + + while (len > 0) { + + switch (opt[off]) { + + case IPV6_TLV_PAD1: + optlen = 1; + break; + default: + if (len < 2) + goto bad; + optlen = opt[off+1]+2; + if (len < optlen) + goto bad; + if (opt[off] & 0x20) + memset(&opt[off+2], 0, opt[off+1]); + break; + } + + off += optlen; + len -= optlen; + } + if (len == 0) + return true; + +bad: + return false; +} + +#if IS_ENABLED(CONFIG_IPV6_MIP6) +/** + * ipv6_rearrange_destopt - rearrange IPv6 destination options header + * @iph: IPv6 header + * @destopt: destionation options header + */ +static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) +{ + u8 *opt = (u8 *)destopt; + int len = ipv6_optlen(destopt); + int off = 0; + int optlen = 0; + + off += 2; + len -= 2; + + while (len > 0) { + + switch (opt[off]) { + + case IPV6_TLV_PAD1: + optlen = 1; + break; + default: + if (len < 2) + goto bad; + optlen = opt[off+1]+2; + if (len < optlen) + goto bad; + + /* Rearrange the source address in @iph and the + * addresses in home address option for final source. + * See 11.3.2 of RFC 3775 for details. + */ + if (opt[off] == IPV6_TLV_HAO) { + struct ipv6_destopt_hao *hao; + + hao = (struct ipv6_destopt_hao *)&opt[off]; + if (hao->length != sizeof(hao->addr)) { + net_warn_ratelimited("destopt hao: invalid header length: %u\n", + hao->length); + goto bad; + } + swap(hao->addr, iph->saddr); + } + break; + } + + off += optlen; + len -= optlen; + } + /* Note: ok if len == 0 */ +bad: + return; +} +#else +static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {} +#endif + +/** + * ipv6_rearrange_rthdr - rearrange IPv6 routing header + * @iph: IPv6 header + * @rthdr: routing header + * + * Rearrange the destination address in @iph and the addresses in @rthdr + * so that they appear in the order they will at the final destination. + * See Appendix A2 of RFC 2402 for details. + */ +static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr) +{ + int segments, segments_left; + struct in6_addr *addrs; + struct in6_addr final_addr; + + segments_left = rthdr->segments_left; + if (segments_left == 0) + return; + rthdr->segments_left = 0; + + /* The value of rthdr->hdrlen has been verified either by the system + * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming + * packets. So we can assume that it is even and that segments is + * greater than or equal to segments_left. + * + * For the same reason we can assume that this option is of type 0. + */ + segments = rthdr->hdrlen >> 1; + + addrs = ((struct rt0_hdr *)rthdr)->addr; + final_addr = addrs[segments - 1]; + + addrs += segments - segments_left; + memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs)); + + addrs[0] = iph->daddr; + iph->daddr = final_addr; +} + +static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir) +{ + union { + struct ipv6hdr *iph; + struct ipv6_opt_hdr *opth; + struct ipv6_rt_hdr *rth; + char *raw; + } exthdr = { .iph = iph }; + char *end = exthdr.raw + len; + int nexthdr = iph->nexthdr; + + exthdr.iph++; + + while (exthdr.raw < end) { + switch (nexthdr) { + case NEXTHDR_DEST: + if (dir == XFRM_POLICY_OUT) + ipv6_rearrange_destopt(iph, exthdr.opth); + fallthrough; + case NEXTHDR_HOP: + if (!zero_out_mutable_opts(exthdr.opth)) { + net_dbg_ratelimited("overrun %sopts\n", + nexthdr == NEXTHDR_HOP ? + "hop" : "dest"); + return -EINVAL; + } + break; + + case NEXTHDR_ROUTING: + ipv6_rearrange_rthdr(iph, exthdr.rth); + break; + + default: + return 0; + } + + nexthdr = exthdr.opth->nexthdr; + exthdr.raw += ipv6_optlen(exthdr.opth); + } + + return 0; +} + +static void ah6_output_done(void *data, int err) +{ + int extlen; + u8 *iph_base; + u8 *icv; + struct sk_buff *skb = data; + struct xfrm_state *x = skb_dst(skb)->xfrm; + struct ah_data *ahp = x->data; + struct ipv6hdr *top_iph = ipv6_hdr(skb); + struct ip_auth_hdr *ah = ip_auth_hdr(skb); + struct tmp_ext *iph_ext; + + extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr); + if (extlen) + extlen += sizeof(*iph_ext); + + iph_base = AH_SKB_CB(skb)->tmp; + iph_ext = ah_tmp_ext(iph_base); + icv = ah_tmp_icv(ahp->ahash, iph_ext, extlen); + + memcpy(ah->auth_data, icv, ahp->icv_trunc_len); + memcpy(top_iph, iph_base, IPV6HDR_BASELEN); + + if (extlen) { +#if IS_ENABLED(CONFIG_IPV6_MIP6) + memcpy(&top_iph->saddr, iph_ext, extlen); +#else + memcpy(&top_iph->daddr, iph_ext, extlen); +#endif + } + + kfree(AH_SKB_CB(skb)->tmp); + xfrm_output_resume(skb->sk, skb, err); +} + +static int ah6_output(struct xfrm_state *x, struct sk_buff *skb) +{ + int err; + int nfrags; + int extlen; + u8 *iph_base; + u8 *icv; + u8 nexthdr; + struct sk_buff *trailer; + struct crypto_ahash *ahash; + struct ahash_request *req; + struct scatterlist *sg; + struct ipv6hdr *top_iph; + struct ip_auth_hdr *ah; + struct ah_data *ahp; + struct tmp_ext *iph_ext; + int seqhi_len = 0; + __be32 *seqhi; + int sglists = 0; + struct scatterlist *seqhisg; + + ahp = x->data; + ahash = ahp->ahash; + + err = skb_cow_data(skb, 0, &trailer); + if (err < 0) + goto out; + nfrags = err; + + skb_push(skb, -skb_network_offset(skb)); + extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr); + if (extlen) + extlen += sizeof(*iph_ext); + + if (x->props.flags & XFRM_STATE_ESN) { + sglists = 1; + seqhi_len = sizeof(*seqhi); + } + err = -ENOMEM; + iph_base = ah_alloc_tmp(ahash, nfrags + sglists, IPV6HDR_BASELEN + + extlen + seqhi_len); + if (!iph_base) + goto out; + + iph_ext = ah_tmp_ext(iph_base); + seqhi = (__be32 *)((char *)iph_ext + extlen); + icv = ah_tmp_icv(ahash, seqhi, seqhi_len); + req = ah_tmp_req(ahash, icv); + sg = ah_req_sg(ahash, req); + seqhisg = sg + nfrags; + + ah = ip_auth_hdr(skb); + memset(ah->auth_data, 0, ahp->icv_trunc_len); + + top_iph = ipv6_hdr(skb); + top_iph->payload_len = htons(skb->len - sizeof(*top_iph)); + + nexthdr = *skb_mac_header(skb); + *skb_mac_header(skb) = IPPROTO_AH; + + /* When there are no extension headers, we only need to save the first + * 8 bytes of the base IP header. + */ + memcpy(iph_base, top_iph, IPV6HDR_BASELEN); + + if (extlen) { +#if IS_ENABLED(CONFIG_IPV6_MIP6) + memcpy(iph_ext, &top_iph->saddr, extlen); +#else + memcpy(iph_ext, &top_iph->daddr, extlen); +#endif + err = ipv6_clear_mutable_options(top_iph, + extlen - sizeof(*iph_ext) + + sizeof(*top_iph), + XFRM_POLICY_OUT); + if (err) + goto out_free; + } + + ah->nexthdr = nexthdr; + + top_iph->priority = 0; + top_iph->flow_lbl[0] = 0; + top_iph->flow_lbl[1] = 0; + top_iph->flow_lbl[2] = 0; + top_iph->hop_limit = 0; + + ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; + + ah->reserved = 0; + ah->spi = x->id.spi; + ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); + + sg_init_table(sg, nfrags + sglists); + err = skb_to_sgvec_nomark(skb, sg, 0, skb->len); + if (unlikely(err < 0)) + goto out_free; + + if (x->props.flags & XFRM_STATE_ESN) { + /* Attach seqhi sg right after packet payload */ + *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); + sg_set_buf(seqhisg, seqhi, seqhi_len); + } + ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len); + ahash_request_set_callback(req, 0, ah6_output_done, skb); + + AH_SKB_CB(skb)->tmp = iph_base; + + err = crypto_ahash_digest(req); + if (err) { + if (err == -EINPROGRESS) + goto out; + + if (err == -ENOSPC) + err = NET_XMIT_DROP; + goto out_free; + } + + memcpy(ah->auth_data, icv, ahp->icv_trunc_len); + memcpy(top_iph, iph_base, IPV6HDR_BASELEN); + + if (extlen) { +#if IS_ENABLED(CONFIG_IPV6_MIP6) + memcpy(&top_iph->saddr, iph_ext, extlen); +#else + memcpy(&top_iph->daddr, iph_ext, extlen); +#endif + } + +out_free: + kfree(iph_base); +out: + return err; +} + +static void ah6_input_done(void *data, int err) +{ + u8 *auth_data; + u8 *icv; + u8 *work_iph; + struct sk_buff *skb = data; + struct xfrm_state *x = xfrm_input_state(skb); + struct ah_data *ahp = x->data; + struct ip_auth_hdr *ah = ip_auth_hdr(skb); + int hdr_len = skb_network_header_len(skb); + int ah_hlen = ipv6_authlen(ah); + + if (err) + goto out; + + work_iph = AH_SKB_CB(skb)->tmp; + auth_data = ah_tmp_auth(work_iph, hdr_len); + icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len); + + err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0; + if (err) + goto out; + + err = ah->nexthdr; + + skb->network_header += ah_hlen; + memcpy(skb_network_header(skb), work_iph, hdr_len); + __skb_pull(skb, ah_hlen + hdr_len); + if (x->props.mode == XFRM_MODE_TUNNEL) + skb_reset_transport_header(skb); + else + skb_set_transport_header(skb, -hdr_len); +out: + kfree(AH_SKB_CB(skb)->tmp); + xfrm_input_resume(skb, err); +} + + + +static int ah6_input(struct xfrm_state *x, struct sk_buff *skb) +{ + /* + * Before process AH + * [IPv6][Ext1][Ext2][AH][Dest][Payload] + * |<-------------->| hdr_len + * + * To erase AH: + * Keeping copy of cleared headers. After AH processing, + * Moving the pointer of skb->network_header by using skb_pull as long + * as AH header length. Then copy back the copy as long as hdr_len + * If destination header following AH exists, copy it into after [Ext2]. + * + * |<>|[IPv6][Ext1][Ext2][Dest][Payload] + * There is offset of AH before IPv6 header after the process. + */ + + u8 *auth_data; + u8 *icv; + u8 *work_iph; + struct sk_buff *trailer; + struct crypto_ahash *ahash; + struct ahash_request *req; + struct scatterlist *sg; + struct ip_auth_hdr *ah; + struct ipv6hdr *ip6h; + struct ah_data *ahp; + u16 hdr_len; + u16 ah_hlen; + int nexthdr; + int nfrags; + int err = -ENOMEM; + int seqhi_len = 0; + __be32 *seqhi; + int sglists = 0; + struct scatterlist *seqhisg; + + if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr))) + goto out; + + /* We are going to _remove_ AH header to keep sockets happy, + * so... Later this can change. */ + if (skb_unclone(skb, GFP_ATOMIC)) + goto out; + + skb->ip_summed = CHECKSUM_NONE; + + hdr_len = skb_network_header_len(skb); + ah = (struct ip_auth_hdr *)skb->data; + ahp = x->data; + ahash = ahp->ahash; + + nexthdr = ah->nexthdr; + ah_hlen = ipv6_authlen(ah); + + if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && + ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) + goto out; + + if (!pskb_may_pull(skb, ah_hlen)) + goto out; + + err = skb_cow_data(skb, 0, &trailer); + if (err < 0) + goto out; + nfrags = err; + + ah = (struct ip_auth_hdr *)skb->data; + ip6h = ipv6_hdr(skb); + + skb_push(skb, hdr_len); + + if (x->props.flags & XFRM_STATE_ESN) { + sglists = 1; + seqhi_len = sizeof(*seqhi); + } + + work_iph = ah_alloc_tmp(ahash, nfrags + sglists, hdr_len + + ahp->icv_trunc_len + seqhi_len); + if (!work_iph) { + err = -ENOMEM; + goto out; + } + + auth_data = ah_tmp_auth((u8 *)work_iph, hdr_len); + seqhi = (__be32 *)(auth_data + ahp->icv_trunc_len); + icv = ah_tmp_icv(ahash, seqhi, seqhi_len); + req = ah_tmp_req(ahash, icv); + sg = ah_req_sg(ahash, req); + seqhisg = sg + nfrags; + + memcpy(work_iph, ip6h, hdr_len); + memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); + memset(ah->auth_data, 0, ahp->icv_trunc_len); + + err = ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN); + if (err) + goto out_free; + + ip6h->priority = 0; + ip6h->flow_lbl[0] = 0; + ip6h->flow_lbl[1] = 0; + ip6h->flow_lbl[2] = 0; + ip6h->hop_limit = 0; + + sg_init_table(sg, nfrags + sglists); + err = skb_to_sgvec_nomark(skb, sg, 0, skb->len); + if (unlikely(err < 0)) + goto out_free; + + if (x->props.flags & XFRM_STATE_ESN) { + /* Attach seqhi sg right after packet payload */ + *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; + sg_set_buf(seqhisg, seqhi, seqhi_len); + } + + ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_len); + ahash_request_set_callback(req, 0, ah6_input_done, skb); + + AH_SKB_CB(skb)->tmp = work_iph; + + err = crypto_ahash_digest(req); + if (err) { + if (err == -EINPROGRESS) + goto out; + + goto out_free; + } + + err = crypto_memneq(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG : 0; + if (err) + goto out_free; + + skb->network_header += ah_hlen; + memcpy(skb_network_header(skb), work_iph, hdr_len); + __skb_pull(skb, ah_hlen + hdr_len); + + if (x->props.mode == XFRM_MODE_TUNNEL) + skb_reset_transport_header(skb); + else + skb_set_transport_header(skb, -hdr_len); + + err = nexthdr; + +out_free: + kfree(work_iph); +out: + return err; +} + +static int ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, + u8 type, u8 code, int offset, __be32 info) +{ + struct net *net = dev_net(skb->dev); + struct ipv6hdr *iph = (struct ipv6hdr *)skb->data; + struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+offset); + struct xfrm_state *x; + + if (type != ICMPV6_PKT_TOOBIG && + type != NDISC_REDIRECT) + return 0; + + x = xfrm_state_lookup(net, skb->mark, (xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6); + if (!x) + return 0; + + if (type == NDISC_REDIRECT) + ip6_redirect(skb, net, skb->dev->ifindex, 0, + sock_net_uid(net, NULL)); + else + ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); + xfrm_state_put(x); + + return 0; +} + +static int ah6_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack) +{ + struct ah_data *ahp = NULL; + struct xfrm_algo_desc *aalg_desc; + struct crypto_ahash *ahash; + + if (!x->aalg) { + NL_SET_ERR_MSG(extack, "AH requires a state with an AUTH algorithm"); + goto error; + } + + if (x->encap) { + NL_SET_ERR_MSG(extack, "AH is not compatible with encapsulation"); + goto error; + } + + ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); + if (!ahp) + return -ENOMEM; + + ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); + if (IS_ERR(ahash)) { + NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); + goto error; + } + + ahp->ahash = ahash; + if (crypto_ahash_setkey(ahash, x->aalg->alg_key, + (x->aalg->alg_key_len + 7) / 8)) { + NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); + goto error; + } + + /* + * Lookup the algorithm description maintained by xfrm_algo, + * verify crypto transform properties, and store information + * we need for AH processing. This lookup cannot fail here + * after a successful crypto_alloc_hash(). + */ + aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); + BUG_ON(!aalg_desc); + + if (aalg_desc->uinfo.auth.icv_fullbits/8 != + crypto_ahash_digestsize(ahash)) { + NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); + goto error; + } + + ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; + ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; + + x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + + ahp->icv_trunc_len); + switch (x->props.mode) { + case XFRM_MODE_BEET: + case XFRM_MODE_TRANSPORT: + break; + case XFRM_MODE_TUNNEL: + x->props.header_len += sizeof(struct ipv6hdr); + break; + default: + NL_SET_ERR_MSG(extack, "Invalid mode requested for AH, must be one of TRANSPORT, TUNNEL, BEET"); + goto error; + } + x->data = ahp; + + return 0; + +error: + if (ahp) { + crypto_free_ahash(ahp->ahash); + kfree(ahp); + } + return -EINVAL; +} + +static void ah6_destroy(struct xfrm_state *x) +{ + struct ah_data *ahp = x->data; + + if (!ahp) + return; + + crypto_free_ahash(ahp->ahash); + kfree(ahp); +} + +static int ah6_rcv_cb(struct sk_buff *skb, int err) +{ + return 0; +} + +static const struct xfrm_type ah6_type = { + .owner = THIS_MODULE, + .proto = IPPROTO_AH, + .flags = XFRM_TYPE_REPLAY_PROT, + .init_state = ah6_init_state, + .destructor = ah6_destroy, + .input = ah6_input, + .output = ah6_output, +}; + +static struct xfrm6_protocol ah6_protocol = { + .handler = xfrm6_rcv, + .input_handler = xfrm_input, + .cb_handler = ah6_rcv_cb, + .err_handler = ah6_err, + .priority = 0, +}; + +static int __init ah6_init(void) +{ + if (xfrm_register_type(&ah6_type, AF_INET6) < 0) { + pr_info("%s: can't add xfrm type\n", __func__); + return -EAGAIN; + } + + if (xfrm6_protocol_register(&ah6_protocol, IPPROTO_AH) < 0) { + pr_info("%s: can't add protocol\n", __func__); + xfrm_unregister_type(&ah6_type, AF_INET6); + return -EAGAIN; + } + + return 0; +} + +static void __exit ah6_fini(void) +{ + if (xfrm6_protocol_deregister(&ah6_protocol, IPPROTO_AH) < 0) + pr_info("%s: can't remove protocol\n", __func__); + + xfrm_unregister_type(&ah6_type, AF_INET6); +} + +module_init(ah6_init); +module_exit(ah6_fini); + +MODULE_LICENSE("GPL"); +MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH); |