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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /security/apparmor/match.c
downloadlinux-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 'security/apparmor/match.c')
-rw-r--r--security/apparmor/match.c790
1 files changed, 790 insertions, 0 deletions
diff --git a/security/apparmor/match.c b/security/apparmor/match.c
new file mode 100644
index 000000000..b97ef5e1d
--- /dev/null
+++ b/security/apparmor/match.c
@@ -0,0 +1,790 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor dfa based regular expression matching engine
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2012 Canonical Ltd.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/err.h>
+#include <linux/kref.h>
+
+#include "include/lib.h"
+#include "include/match.h"
+
+#define base_idx(X) ((X) & 0xffffff)
+
+static char nulldfa_src[] = {
+ #include "nulldfa.in"
+};
+struct aa_dfa *nulldfa;
+
+static char stacksplitdfa_src[] = {
+ #include "stacksplitdfa.in"
+};
+struct aa_dfa *stacksplitdfa;
+
+int __init aa_setup_dfa_engine(void)
+{
+ int error;
+
+ nulldfa = aa_dfa_unpack(nulldfa_src, sizeof(nulldfa_src),
+ TO_ACCEPT1_FLAG(YYTD_DATA32) |
+ TO_ACCEPT2_FLAG(YYTD_DATA32));
+ if (IS_ERR(nulldfa)) {
+ error = PTR_ERR(nulldfa);
+ nulldfa = NULL;
+ return error;
+ }
+
+ stacksplitdfa = aa_dfa_unpack(stacksplitdfa_src,
+ sizeof(stacksplitdfa_src),
+ TO_ACCEPT1_FLAG(YYTD_DATA32) |
+ TO_ACCEPT2_FLAG(YYTD_DATA32));
+ if (IS_ERR(stacksplitdfa)) {
+ aa_put_dfa(nulldfa);
+ nulldfa = NULL;
+ error = PTR_ERR(stacksplitdfa);
+ stacksplitdfa = NULL;
+ return error;
+ }
+
+ return 0;
+}
+
+void __init aa_teardown_dfa_engine(void)
+{
+ aa_put_dfa(stacksplitdfa);
+ aa_put_dfa(nulldfa);
+}
+
+/**
+ * unpack_table - unpack a dfa table (one of accept, default, base, next check)
+ * @blob: data to unpack (NOT NULL)
+ * @bsize: size of blob
+ *
+ * Returns: pointer to table else NULL on failure
+ *
+ * NOTE: must be freed by kvfree (not kfree)
+ */
+static struct table_header *unpack_table(char *blob, size_t bsize)
+{
+ struct table_header *table = NULL;
+ struct table_header th;
+ size_t tsize;
+
+ if (bsize < sizeof(struct table_header))
+ goto out;
+
+ /* loaded td_id's start at 1, subtract 1 now to avoid doing
+ * it every time we use td_id as an index
+ */
+ th.td_id = be16_to_cpu(*(__be16 *) (blob)) - 1;
+ if (th.td_id > YYTD_ID_MAX)
+ goto out;
+ th.td_flags = be16_to_cpu(*(__be16 *) (blob + 2));
+ th.td_lolen = be32_to_cpu(*(__be32 *) (blob + 8));
+ blob += sizeof(struct table_header);
+
+ if (!(th.td_flags == YYTD_DATA16 || th.td_flags == YYTD_DATA32 ||
+ th.td_flags == YYTD_DATA8))
+ goto out;
+
+ /* if we have a table it must have some entries */
+ if (th.td_lolen == 0)
+ goto out;
+ tsize = table_size(th.td_lolen, th.td_flags);
+ if (bsize < tsize)
+ goto out;
+
+ table = kvzalloc(tsize, GFP_KERNEL);
+ if (table) {
+ table->td_id = th.td_id;
+ table->td_flags = th.td_flags;
+ table->td_lolen = th.td_lolen;
+ if (th.td_flags == YYTD_DATA8)
+ UNPACK_ARRAY(table->td_data, blob, th.td_lolen,
+ u8, u8, byte_to_byte);
+ else if (th.td_flags == YYTD_DATA16)
+ UNPACK_ARRAY(table->td_data, blob, th.td_lolen,
+ u16, __be16, be16_to_cpu);
+ else if (th.td_flags == YYTD_DATA32)
+ UNPACK_ARRAY(table->td_data, blob, th.td_lolen,
+ u32, __be32, be32_to_cpu);
+ else
+ goto fail;
+ /* if table was vmalloced make sure the page tables are synced
+ * before it is used, as it goes live to all cpus.
+ */
+ if (is_vmalloc_addr(table))
+ vm_unmap_aliases();
+ }
+
+out:
+ return table;
+fail:
+ kvfree(table);
+ return NULL;
+}
+
+/**
+ * verify_table_headers - verify that the tables headers are as expected
+ * @tables - array of dfa tables to check (NOT NULL)
+ * @flags: flags controlling what type of accept table are acceptable
+ *
+ * Assumes dfa has gone through the first pass verification done by unpacking
+ * NOTE: this does not valid accept table values
+ *
+ * Returns: %0 else error code on failure to verify
+ */
+static int verify_table_headers(struct table_header **tables, int flags)
+{
+ size_t state_count, trans_count;
+ int error = -EPROTO;
+
+ /* check that required tables exist */
+ if (!(tables[YYTD_ID_DEF] && tables[YYTD_ID_BASE] &&
+ tables[YYTD_ID_NXT] && tables[YYTD_ID_CHK]))
+ goto out;
+
+ /* accept.size == default.size == base.size */
+ state_count = tables[YYTD_ID_BASE]->td_lolen;
+ if (ACCEPT1_FLAGS(flags)) {
+ if (!tables[YYTD_ID_ACCEPT])
+ goto out;
+ if (state_count != tables[YYTD_ID_ACCEPT]->td_lolen)
+ goto out;
+ }
+ if (ACCEPT2_FLAGS(flags)) {
+ if (!tables[YYTD_ID_ACCEPT2])
+ goto out;
+ if (state_count != tables[YYTD_ID_ACCEPT2]->td_lolen)
+ goto out;
+ }
+ if (state_count != tables[YYTD_ID_DEF]->td_lolen)
+ goto out;
+
+ /* next.size == chk.size */
+ trans_count = tables[YYTD_ID_NXT]->td_lolen;
+ if (trans_count != tables[YYTD_ID_CHK]->td_lolen)
+ goto out;
+
+ /* if equivalence classes then its table size must be 256 */
+ if (tables[YYTD_ID_EC] && tables[YYTD_ID_EC]->td_lolen != 256)
+ goto out;
+
+ error = 0;
+out:
+ return error;
+}
+
+/**
+ * verify_dfa - verify that transitions and states in the tables are in bounds.
+ * @dfa: dfa to test (NOT NULL)
+ *
+ * Assumes dfa has gone through the first pass verification done by unpacking
+ * NOTE: this does not valid accept table values
+ *
+ * Returns: %0 else error code on failure to verify
+ */
+static int verify_dfa(struct aa_dfa *dfa)
+{
+ size_t i, state_count, trans_count;
+ int error = -EPROTO;
+
+ state_count = dfa->tables[YYTD_ID_BASE]->td_lolen;
+ trans_count = dfa->tables[YYTD_ID_NXT]->td_lolen;
+ if (state_count == 0)
+ goto out;
+ for (i = 0; i < state_count; i++) {
+ if (!(BASE_TABLE(dfa)[i] & MATCH_FLAG_DIFF_ENCODE) &&
+ (DEFAULT_TABLE(dfa)[i] >= state_count))
+ goto out;
+ if (BASE_TABLE(dfa)[i] & MATCH_FLAGS_INVALID) {
+ pr_err("AppArmor DFA state with invalid match flags");
+ goto out;
+ }
+ if ((BASE_TABLE(dfa)[i] & MATCH_FLAG_DIFF_ENCODE)) {
+ if (!(dfa->flags & YYTH_FLAG_DIFF_ENCODE)) {
+ pr_err("AppArmor DFA diff encoded transition state without header flag");
+ goto out;
+ }
+ }
+ if ((BASE_TABLE(dfa)[i] & MATCH_FLAG_OOB_TRANSITION)) {
+ if (base_idx(BASE_TABLE(dfa)[i]) < dfa->max_oob) {
+ pr_err("AppArmor DFA out of bad transition out of range");
+ goto out;
+ }
+ if (!(dfa->flags & YYTH_FLAG_OOB_TRANS)) {
+ pr_err("AppArmor DFA out of bad transition state without header flag");
+ goto out;
+ }
+ }
+ if (base_idx(BASE_TABLE(dfa)[i]) + 255 >= trans_count) {
+ pr_err("AppArmor DFA next/check upper bounds error\n");
+ goto out;
+ }
+ }
+
+ for (i = 0; i < trans_count; i++) {
+ if (NEXT_TABLE(dfa)[i] >= state_count)
+ goto out;
+ if (CHECK_TABLE(dfa)[i] >= state_count)
+ goto out;
+ }
+
+ /* Now that all the other tables are verified, verify diffencoding */
+ for (i = 0; i < state_count; i++) {
+ size_t j, k;
+
+ for (j = i;
+ (BASE_TABLE(dfa)[j] & MATCH_FLAG_DIFF_ENCODE) &&
+ !(BASE_TABLE(dfa)[j] & MARK_DIFF_ENCODE);
+ j = k) {
+ k = DEFAULT_TABLE(dfa)[j];
+ if (j == k)
+ goto out;
+ if (k < j)
+ break; /* already verified */
+ BASE_TABLE(dfa)[j] |= MARK_DIFF_ENCODE;
+ }
+ }
+ error = 0;
+
+out:
+ return error;
+}
+
+/**
+ * dfa_free - free a dfa allocated by aa_dfa_unpack
+ * @dfa: the dfa to free (MAYBE NULL)
+ *
+ * Requires: reference count to dfa == 0
+ */
+static void dfa_free(struct aa_dfa *dfa)
+{
+ if (dfa) {
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dfa->tables); i++) {
+ kvfree(dfa->tables[i]);
+ dfa->tables[i] = NULL;
+ }
+ kfree(dfa);
+ }
+}
+
+/**
+ * aa_dfa_free_kref - free aa_dfa by kref (called by aa_put_dfa)
+ * @kr: kref callback for freeing of a dfa (NOT NULL)
+ */
+void aa_dfa_free_kref(struct kref *kref)
+{
+ struct aa_dfa *dfa = container_of(kref, struct aa_dfa, count);
+ dfa_free(dfa);
+}
+
+/**
+ * aa_dfa_unpack - unpack the binary tables of a serialized dfa
+ * @blob: aligned serialized stream of data to unpack (NOT NULL)
+ * @size: size of data to unpack
+ * @flags: flags controlling what type of accept tables are acceptable
+ *
+ * Unpack a dfa that has been serialized. To find information on the dfa
+ * format look in Documentation/admin-guide/LSM/apparmor.rst
+ * Assumes the dfa @blob stream has been aligned on a 8 byte boundary
+ *
+ * Returns: an unpacked dfa ready for matching or ERR_PTR on failure
+ */
+struct aa_dfa *aa_dfa_unpack(void *blob, size_t size, int flags)
+{
+ int hsize;
+ int error = -ENOMEM;
+ char *data = blob;
+ struct table_header *table = NULL;
+ struct aa_dfa *dfa = kzalloc(sizeof(struct aa_dfa), GFP_KERNEL);
+ if (!dfa)
+ goto fail;
+
+ kref_init(&dfa->count);
+
+ error = -EPROTO;
+
+ /* get dfa table set header */
+ if (size < sizeof(struct table_set_header))
+ goto fail;
+
+ if (ntohl(*(__be32 *) data) != YYTH_MAGIC)
+ goto fail;
+
+ hsize = ntohl(*(__be32 *) (data + 4));
+ if (size < hsize)
+ goto fail;
+
+ dfa->flags = ntohs(*(__be16 *) (data + 12));
+ if (dfa->flags & ~(YYTH_FLAGS))
+ goto fail;
+
+ /*
+ * TODO: needed for dfa to support more than 1 oob
+ * if (dfa->flags & YYTH_FLAGS_OOB_TRANS) {
+ * if (hsize < 16 + 4)
+ * goto fail;
+ * dfa->max_oob = ntol(*(__be32 *) (data + 16));
+ * if (dfa->max <= MAX_OOB_SUPPORTED) {
+ * pr_err("AppArmor DFA OOB greater than supported\n");
+ * goto fail;
+ * }
+ * }
+ */
+ dfa->max_oob = 1;
+
+ data += hsize;
+ size -= hsize;
+
+ while (size > 0) {
+ table = unpack_table(data, size);
+ if (!table)
+ goto fail;
+
+ switch (table->td_id) {
+ case YYTD_ID_ACCEPT:
+ if (!(table->td_flags & ACCEPT1_FLAGS(flags)))
+ goto fail;
+ break;
+ case YYTD_ID_ACCEPT2:
+ if (!(table->td_flags & ACCEPT2_FLAGS(flags)))
+ goto fail;
+ break;
+ case YYTD_ID_BASE:
+ if (table->td_flags != YYTD_DATA32)
+ goto fail;
+ break;
+ case YYTD_ID_DEF:
+ case YYTD_ID_NXT:
+ case YYTD_ID_CHK:
+ if (table->td_flags != YYTD_DATA16)
+ goto fail;
+ break;
+ case YYTD_ID_EC:
+ if (table->td_flags != YYTD_DATA8)
+ goto fail;
+ break;
+ default:
+ goto fail;
+ }
+ /* check for duplicate table entry */
+ if (dfa->tables[table->td_id])
+ goto fail;
+ dfa->tables[table->td_id] = table;
+ data += table_size(table->td_lolen, table->td_flags);
+ size -= table_size(table->td_lolen, table->td_flags);
+ table = NULL;
+ }
+ error = verify_table_headers(dfa->tables, flags);
+ if (error)
+ goto fail;
+
+ if (flags & DFA_FLAG_VERIFY_STATES) {
+ error = verify_dfa(dfa);
+ if (error)
+ goto fail;
+ }
+
+ return dfa;
+
+fail:
+ kvfree(table);
+ dfa_free(dfa);
+ return ERR_PTR(error);
+}
+
+#define match_char(state, def, base, next, check, C) \
+do { \
+ u32 b = (base)[(state)]; \
+ unsigned int pos = base_idx(b) + (C); \
+ if ((check)[pos] != (state)) { \
+ (state) = (def)[(state)]; \
+ if (b & MATCH_FLAG_DIFF_ENCODE) \
+ continue; \
+ break; \
+ } \
+ (state) = (next)[pos]; \
+ break; \
+} while (1)
+
+/**
+ * aa_dfa_match_len - traverse @dfa to find state @str stops at
+ * @dfa: the dfa to match @str against (NOT NULL)
+ * @start: the state of the dfa to start matching in
+ * @str: the string of bytes to match against the dfa (NOT NULL)
+ * @len: length of the string of bytes to match
+ *
+ * aa_dfa_match_len will match @str against the dfa and return the state it
+ * finished matching in. The final state can be used to look up the accepting
+ * label, or as the start state of a continuing match.
+ *
+ * This function will happily match again the 0 byte and only finishes
+ * when @len input is consumed.
+ *
+ * Returns: final state reached after input is consumed
+ */
+aa_state_t aa_dfa_match_len(struct aa_dfa *dfa, aa_state_t start,
+ const char *str, int len)
+{
+ u16 *def = DEFAULT_TABLE(dfa);
+ u32 *base = BASE_TABLE(dfa);
+ u16 *next = NEXT_TABLE(dfa);
+ u16 *check = CHECK_TABLE(dfa);
+ aa_state_t state = start;
+
+ if (state == DFA_NOMATCH)
+ return DFA_NOMATCH;
+
+ /* current state is <state>, matching character *str */
+ if (dfa->tables[YYTD_ID_EC]) {
+ /* Equivalence class table defined */
+ u8 *equiv = EQUIV_TABLE(dfa);
+ for (; len; len--)
+ match_char(state, def, base, next, check,
+ equiv[(u8) *str++]);
+ } else {
+ /* default is direct to next state */
+ for (; len; len--)
+ match_char(state, def, base, next, check, (u8) *str++);
+ }
+
+ return state;
+}
+
+/**
+ * aa_dfa_match - traverse @dfa to find state @str stops at
+ * @dfa: the dfa to match @str against (NOT NULL)
+ * @start: the state of the dfa to start matching in
+ * @str: the null terminated string of bytes to match against the dfa (NOT NULL)
+ *
+ * aa_dfa_match will match @str against the dfa and return the state it
+ * finished matching in. The final state can be used to look up the accepting
+ * label, or as the start state of a continuing match.
+ *
+ * Returns: final state reached after input is consumed
+ */
+aa_state_t aa_dfa_match(struct aa_dfa *dfa, aa_state_t start, const char *str)
+{
+ u16 *def = DEFAULT_TABLE(dfa);
+ u32 *base = BASE_TABLE(dfa);
+ u16 *next = NEXT_TABLE(dfa);
+ u16 *check = CHECK_TABLE(dfa);
+ aa_state_t state = start;
+
+ if (state == DFA_NOMATCH)
+ return DFA_NOMATCH;
+
+ /* current state is <state>, matching character *str */
+ if (dfa->tables[YYTD_ID_EC]) {
+ /* Equivalence class table defined */
+ u8 *equiv = EQUIV_TABLE(dfa);
+ /* default is direct to next state */
+ while (*str)
+ match_char(state, def, base, next, check,
+ equiv[(u8) *str++]);
+ } else {
+ /* default is direct to next state */
+ while (*str)
+ match_char(state, def, base, next, check, (u8) *str++);
+ }
+
+ return state;
+}
+
+/**
+ * aa_dfa_next - step one character to the next state in the dfa
+ * @dfa: the dfa to traverse (NOT NULL)
+ * @state: the state to start in
+ * @c: the input character to transition on
+ *
+ * aa_dfa_match will step through the dfa by one input character @c
+ *
+ * Returns: state reach after input @c
+ */
+aa_state_t aa_dfa_next(struct aa_dfa *dfa, aa_state_t state, const char c)
+{
+ u16 *def = DEFAULT_TABLE(dfa);
+ u32 *base = BASE_TABLE(dfa);
+ u16 *next = NEXT_TABLE(dfa);
+ u16 *check = CHECK_TABLE(dfa);
+
+ /* current state is <state>, matching character *str */
+ if (dfa->tables[YYTD_ID_EC]) {
+ /* Equivalence class table defined */
+ u8 *equiv = EQUIV_TABLE(dfa);
+ match_char(state, def, base, next, check, equiv[(u8) c]);
+ } else
+ match_char(state, def, base, next, check, (u8) c);
+
+ return state;
+}
+
+aa_state_t aa_dfa_outofband_transition(struct aa_dfa *dfa, aa_state_t state)
+{
+ u16 *def = DEFAULT_TABLE(dfa);
+ u32 *base = BASE_TABLE(dfa);
+ u16 *next = NEXT_TABLE(dfa);
+ u16 *check = CHECK_TABLE(dfa);
+ u32 b = (base)[(state)];
+
+ if (!(b & MATCH_FLAG_OOB_TRANSITION))
+ return DFA_NOMATCH;
+
+ /* No Equivalence class remapping for outofband transitions */
+ match_char(state, def, base, next, check, -1);
+
+ return state;
+}
+
+/**
+ * aa_dfa_match_until - traverse @dfa until accept state or end of input
+ * @dfa: the dfa to match @str against (NOT NULL)
+ * @start: the state of the dfa to start matching in
+ * @str: the null terminated string of bytes to match against the dfa (NOT NULL)
+ * @retpos: first character in str after match OR end of string
+ *
+ * aa_dfa_match will match @str against the dfa and return the state it
+ * finished matching in. The final state can be used to look up the accepting
+ * label, or as the start state of a continuing match.
+ *
+ * Returns: final state reached after input is consumed
+ */
+aa_state_t aa_dfa_match_until(struct aa_dfa *dfa, aa_state_t start,
+ const char *str, const char **retpos)
+{
+ u16 *def = DEFAULT_TABLE(dfa);
+ u32 *base = BASE_TABLE(dfa);
+ u16 *next = NEXT_TABLE(dfa);
+ u16 *check = CHECK_TABLE(dfa);
+ u32 *accept = ACCEPT_TABLE(dfa);
+ aa_state_t state = start, pos;
+
+ if (state == DFA_NOMATCH)
+ return DFA_NOMATCH;
+
+ /* current state is <state>, matching character *str */
+ if (dfa->tables[YYTD_ID_EC]) {
+ /* Equivalence class table defined */
+ u8 *equiv = EQUIV_TABLE(dfa);
+ /* default is direct to next state */
+ while (*str) {
+ pos = base_idx(base[state]) + equiv[(u8) *str++];
+ if (check[pos] == state)
+ state = next[pos];
+ else
+ state = def[state];
+ if (accept[state])
+ break;
+ }
+ } else {
+ /* default is direct to next state */
+ while (*str) {
+ pos = base_idx(base[state]) + (u8) *str++;
+ if (check[pos] == state)
+ state = next[pos];
+ else
+ state = def[state];
+ if (accept[state])
+ break;
+ }
+ }
+
+ *retpos = str;
+ return state;
+}
+
+/**
+ * aa_dfa_matchn_until - traverse @dfa until accept or @n bytes consumed
+ * @dfa: the dfa to match @str against (NOT NULL)
+ * @start: the state of the dfa to start matching in
+ * @str: the string of bytes to match against the dfa (NOT NULL)
+ * @n: length of the string of bytes to match
+ * @retpos: first character in str after match OR str + n
+ *
+ * aa_dfa_match_len will match @str against the dfa and return the state it
+ * finished matching in. The final state can be used to look up the accepting
+ * label, or as the start state of a continuing match.
+ *
+ * This function will happily match again the 0 byte and only finishes
+ * when @n input is consumed.
+ *
+ * Returns: final state reached after input is consumed
+ */
+aa_state_t aa_dfa_matchn_until(struct aa_dfa *dfa, aa_state_t start,
+ const char *str, int n, const char **retpos)
+{
+ u16 *def = DEFAULT_TABLE(dfa);
+ u32 *base = BASE_TABLE(dfa);
+ u16 *next = NEXT_TABLE(dfa);
+ u16 *check = CHECK_TABLE(dfa);
+ u32 *accept = ACCEPT_TABLE(dfa);
+ aa_state_t state = start, pos;
+
+ *retpos = NULL;
+ if (state == DFA_NOMATCH)
+ return DFA_NOMATCH;
+
+ /* current state is <state>, matching character *str */
+ if (dfa->tables[YYTD_ID_EC]) {
+ /* Equivalence class table defined */
+ u8 *equiv = EQUIV_TABLE(dfa);
+ /* default is direct to next state */
+ for (; n; n--) {
+ pos = base_idx(base[state]) + equiv[(u8) *str++];
+ if (check[pos] == state)
+ state = next[pos];
+ else
+ state = def[state];
+ if (accept[state])
+ break;
+ }
+ } else {
+ /* default is direct to next state */
+ for (; n; n--) {
+ pos = base_idx(base[state]) + (u8) *str++;
+ if (check[pos] == state)
+ state = next[pos];
+ else
+ state = def[state];
+ if (accept[state])
+ break;
+ }
+ }
+
+ *retpos = str;
+ return state;
+}
+
+#define inc_wb_pos(wb) \
+do { \
+ wb->pos = (wb->pos + 1) & (WB_HISTORY_SIZE - 1); \
+ wb->len = (wb->len + 1) & (WB_HISTORY_SIZE - 1); \
+} while (0)
+
+/* For DFAs that don't support extended tagging of states */
+static bool is_loop(struct match_workbuf *wb, aa_state_t state,
+ unsigned int *adjust)
+{
+ aa_state_t pos = wb->pos;
+ aa_state_t i;
+
+ if (wb->history[pos] < state)
+ return false;
+
+ for (i = 0; i <= wb->len; i++) {
+ if (wb->history[pos] == state) {
+ *adjust = i;
+ return true;
+ }
+ if (pos == 0)
+ pos = WB_HISTORY_SIZE;
+ pos--;
+ }
+
+ *adjust = i;
+ return true;
+}
+
+static aa_state_t leftmatch_fb(struct aa_dfa *dfa, aa_state_t start,
+ const char *str, struct match_workbuf *wb,
+ unsigned int *count)
+{
+ u16 *def = DEFAULT_TABLE(dfa);
+ u32 *base = BASE_TABLE(dfa);
+ u16 *next = NEXT_TABLE(dfa);
+ u16 *check = CHECK_TABLE(dfa);
+ aa_state_t state = start, pos;
+
+ AA_BUG(!dfa);
+ AA_BUG(!str);
+ AA_BUG(!wb);
+ AA_BUG(!count);
+
+ *count = 0;
+ if (state == DFA_NOMATCH)
+ return DFA_NOMATCH;
+
+ /* current state is <state>, matching character *str */
+ if (dfa->tables[YYTD_ID_EC]) {
+ /* Equivalence class table defined */
+ u8 *equiv = EQUIV_TABLE(dfa);
+ /* default is direct to next state */
+ while (*str) {
+ unsigned int adjust;
+
+ wb->history[wb->pos] = state;
+ pos = base_idx(base[state]) + equiv[(u8) *str++];
+ if (check[pos] == state)
+ state = next[pos];
+ else
+ state = def[state];
+ if (is_loop(wb, state, &adjust)) {
+ state = aa_dfa_match(dfa, state, str);
+ *count -= adjust;
+ goto out;
+ }
+ inc_wb_pos(wb);
+ (*count)++;
+ }
+ } else {
+ /* default is direct to next state */
+ while (*str) {
+ unsigned int adjust;
+
+ wb->history[wb->pos] = state;
+ pos = base_idx(base[state]) + (u8) *str++;
+ if (check[pos] == state)
+ state = next[pos];
+ else
+ state = def[state];
+ if (is_loop(wb, state, &adjust)) {
+ state = aa_dfa_match(dfa, state, str);
+ *count -= adjust;
+ goto out;
+ }
+ inc_wb_pos(wb);
+ (*count)++;
+ }
+ }
+
+out:
+ if (!state)
+ *count = 0;
+ return state;
+}
+
+/**
+ * aa_dfa_leftmatch - traverse @dfa to find state @str stops at
+ * @dfa: the dfa to match @str against (NOT NULL)
+ * @start: the state of the dfa to start matching in
+ * @str: the null terminated string of bytes to match against the dfa (NOT NULL)
+ * @count: current count of longest left.
+ *
+ * aa_dfa_match will match @str against the dfa and return the state it
+ * finished matching in. The final state can be used to look up the accepting
+ * label, or as the start state of a continuing match.
+ *
+ * Returns: final state reached after input is consumed
+ */
+aa_state_t aa_dfa_leftmatch(struct aa_dfa *dfa, aa_state_t start,
+ const char *str, unsigned int *count)
+{
+ DEFINE_MATCH_WB(wb);
+
+ /* TODO: match for extended state dfas */
+
+ return leftmatch_fb(dfa, start, str, &wb, count);
+}