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().
  ...

1 files changed, 603 insertions, 0 deletions

diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c
new file mode 100644
index 000000000..c8a248bd1
--- /dev/null
+++ b/drivers/target/iscsi/iscsi_target_auth.c
@@ -0,0 +1,603 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ * This file houses the main functions for the iSCSI CHAP support
+ *
+ * (c) Copyright 2007-2013 Datera, Inc.
+ *
+ * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
+ *
+ ******************************************************************************/
+
+#include <crypto/hash.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <linux/random.h>
+#include <linux/scatterlist.h>
+#include <target/iscsi/iscsi_target_core.h>
+#include "iscsi_target_nego.h"
+#include "iscsi_target_auth.h"
+
+static char *chap_get_digest_name(const int digest_type)
+{
+	switch (digest_type) {
+	case CHAP_DIGEST_MD5:
+		return "md5";
+	case CHAP_DIGEST_SHA1:
+		return "sha1";
+	case CHAP_DIGEST_SHA256:
+		return "sha256";
+	case CHAP_DIGEST_SHA3_256:
+		return "sha3-256";
+	default:
+		return NULL;
+	}
+}
+
+static int chap_gen_challenge(
+	struct iscsit_conn *conn,
+	int caller,
+	char *c_str,
+	unsigned int *c_len)
+{
+	int ret;
+	unsigned char *challenge_asciihex;
+	struct iscsi_chap *chap = conn->auth_protocol;
+
+	challenge_asciihex = kzalloc(chap->challenge_len * 2 + 1, GFP_KERNEL);
+	if (!challenge_asciihex)
+		return -ENOMEM;
+
+	memset(chap->challenge, 0, MAX_CHAP_CHALLENGE_LEN);
+
+	ret = get_random_bytes_wait(chap->challenge, chap->challenge_len);
+	if (unlikely(ret))
+		goto out;
+
+	bin2hex(challenge_asciihex, chap->challenge,
+				chap->challenge_len);
+	/*
+	 * Set CHAP_C, and copy the generated challenge into c_str.
+	 */
+	*c_len += sprintf(c_str + *c_len, "CHAP_C=0x%s", challenge_asciihex);
+	*c_len += 1;
+
+	pr_debug("[%s] Sending CHAP_C=0x%s\n\n", (caller) ? "server" : "client",
+			challenge_asciihex);
+
+out:
+	kfree(challenge_asciihex);
+	return ret;
+}
+
+static int chap_test_algorithm(const char *name)
+{
+	struct crypto_shash *tfm;
+
+	tfm = crypto_alloc_shash(name, 0, 0);
+	if (IS_ERR(tfm))
+		return -1;
+
+	crypto_free_shash(tfm);
+	return 0;
+}
+
+static int chap_check_algorithm(const char *a_str)
+{
+	char *tmp, *orig, *token, *digest_name;
+	long digest_type;
+	int r = CHAP_DIGEST_UNKNOWN;
+
+	tmp = kstrdup(a_str, GFP_KERNEL);
+	if (!tmp) {
+		pr_err("Memory allocation failed for CHAP_A temporary buffer\n");
+		return CHAP_DIGEST_UNKNOWN;
+	}
+	orig = tmp;
+
+	token = strsep(&tmp, "=");
+	if (!token)
+		goto out;
+
+	if (strcmp(token, "CHAP_A")) {
+		pr_err("Unable to locate CHAP_A key\n");
+		goto out;
+	}
+	while (token) {
+		token = strsep(&tmp, ",");
+		if (!token)
+			goto out;
+
+		if (kstrtol(token, 10, &digest_type))
+			continue;
+
+		digest_name = chap_get_digest_name(digest_type);
+		if (!digest_name)
+			continue;
+
+		pr_debug("Selected %s Algorithm\n", digest_name);
+		if (chap_test_algorithm(digest_name) < 0) {
+			pr_err("failed to allocate %s algo\n", digest_name);
+		} else {
+			r = digest_type;
+			goto out;
+		}
+	}
+out:
+	kfree(orig);
+	return r;
+}
+
+static void chap_close(struct iscsit_conn *conn)
+{
+	kfree(conn->auth_protocol);
+	conn->auth_protocol = NULL;
+}
+
+static struct iscsi_chap *chap_server_open(
+	struct iscsit_conn *conn,
+	struct iscsi_node_auth *auth,
+	const char *a_str,
+	char *aic_str,
+	unsigned int *aic_len)
+{
+	int digest_type;
+	struct iscsi_chap *chap;
+
+	if (!(auth->naf_flags & NAF_USERID_SET) ||
+	    !(auth->naf_flags & NAF_PASSWORD_SET)) {
+		pr_err("CHAP user or password not set for"
+				" Initiator ACL\n");
+		return NULL;
+	}
+
+	conn->auth_protocol = kzalloc(sizeof(struct iscsi_chap), GFP_KERNEL);
+	if (!conn->auth_protocol)
+		return NULL;
+
+	chap = conn->auth_protocol;
+	digest_type = chap_check_algorithm(a_str);
+	switch (digest_type) {
+	case CHAP_DIGEST_MD5:
+		chap->digest_size = MD5_SIGNATURE_SIZE;
+		break;
+	case CHAP_DIGEST_SHA1:
+		chap->digest_size = SHA1_SIGNATURE_SIZE;
+		break;
+	case CHAP_DIGEST_SHA256:
+		chap->digest_size = SHA256_SIGNATURE_SIZE;
+		break;
+	case CHAP_DIGEST_SHA3_256:
+		chap->digest_size = SHA3_256_SIGNATURE_SIZE;
+		break;
+	case CHAP_DIGEST_UNKNOWN:
+	default:
+		pr_err("Unsupported CHAP_A value\n");
+		chap_close(conn);
+		return NULL;
+	}
+
+	chap->digest_name = chap_get_digest_name(digest_type);
+
+	/* Tie the challenge length to the digest size */
+	chap->challenge_len = chap->digest_size;
+
+	pr_debug("[server] Got CHAP_A=%d\n", digest_type);
+	*aic_len = sprintf(aic_str, "CHAP_A=%d", digest_type);
+	*aic_len += 1;
+	pr_debug("[server] Sending CHAP_A=%d\n", digest_type);
+
+	/*
+	 * Set Identifier.
+	 */
+	chap->id = conn->tpg->tpg_chap_id++;
+	*aic_len += sprintf(aic_str + *aic_len, "CHAP_I=%d", chap->id);
+	*aic_len += 1;
+	pr_debug("[server] Sending CHAP_I=%d\n", chap->id);
+	/*
+	 * Generate Challenge.
+	 */
+	if (chap_gen_challenge(conn, 1, aic_str, aic_len) < 0) {
+		chap_close(conn);
+		return NULL;
+	}
+
+	return chap;
+}
+
+static const char base64_lookup_table[] =
+	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+static int chap_base64_decode(u8 *dst, const char *src, size_t len)
+{
+	int i, bits = 0, ac = 0;
+	const char *p;
+	u8 *cp = dst;
+
+	for (i = 0; i < len; i++) {
+		if (src[i] == '=')
+			return cp - dst;
+
+		p = strchr(base64_lookup_table, src[i]);
+		if (p == NULL || src[i] == 0)
+			return -2;
+
+		ac <<= 6;
+		ac += (p - base64_lookup_table);
+		bits += 6;
+		if (bits >= 8) {
+			*cp++ = (ac >> (bits - 8)) & 0xff;
+			ac &= ~(BIT(16) - BIT(bits - 8));
+			bits -= 8;
+		}
+	}
+	if (ac)
+		return -1;
+
+	return cp - dst;
+}
+
+static int chap_server_compute_hash(
+	struct iscsit_conn *conn,
+	struct iscsi_node_auth *auth,
+	char *nr_in_ptr,
+	char *nr_out_ptr,
+	unsigned int *nr_out_len)
+{
+	unsigned long id;
+	unsigned char id_as_uchar;
+	unsigned char type;
+	unsigned char identifier[10], *initiatorchg = NULL;
+	unsigned char *initiatorchg_binhex = NULL;
+	unsigned char *digest = NULL;
+	unsigned char *response = NULL;
+	unsigned char *client_digest = NULL;
+	unsigned char *server_digest = NULL;
+	unsigned char chap_n[MAX_CHAP_N_SIZE], chap_r[MAX_RESPONSE_LENGTH];
+	size_t compare_len;
+	struct iscsi_chap *chap = conn->auth_protocol;
+	struct crypto_shash *tfm = NULL;
+	struct shash_desc *desc = NULL;
+	int auth_ret = -1, ret, initiatorchg_len;
+
+	digest = kzalloc(chap->digest_size, GFP_KERNEL);
+	if (!digest) {
+		pr_err("Unable to allocate the digest buffer\n");
+		goto out;
+	}
+
+	response = kzalloc(chap->digest_size * 2 + 2, GFP_KERNEL);
+	if (!response) {
+		pr_err("Unable to allocate the response buffer\n");
+		goto out;
+	}
+
+	client_digest = kzalloc(chap->digest_size, GFP_KERNEL);
+	if (!client_digest) {
+		pr_err("Unable to allocate the client_digest buffer\n");
+		goto out;
+	}
+
+	server_digest = kzalloc(chap->digest_size, GFP_KERNEL);
+	if (!server_digest) {
+		pr_err("Unable to allocate the server_digest buffer\n");
+		goto out;
+	}
+
+	memset(identifier, 0, 10);
+	memset(chap_n, 0, MAX_CHAP_N_SIZE);
+	memset(chap_r, 0, MAX_RESPONSE_LENGTH);
+
+	initiatorchg = kzalloc(CHAP_CHALLENGE_STR_LEN, GFP_KERNEL);
+	if (!initiatorchg) {
+		pr_err("Unable to allocate challenge buffer\n");
+		goto out;
+	}
+
+	initiatorchg_binhex = kzalloc(CHAP_CHALLENGE_STR_LEN, GFP_KERNEL);
+	if (!initiatorchg_binhex) {
+		pr_err("Unable to allocate initiatorchg_binhex buffer\n");
+		goto out;
+	}
+	/*
+	 * Extract CHAP_N.
+	 */
+	if (extract_param(nr_in_ptr, "CHAP_N", MAX_CHAP_N_SIZE, chap_n,
+				&type) < 0) {
+		pr_err("Could not find CHAP_N.\n");
+		goto out;
+	}
+	if (type == HEX) {
+		pr_err("Could not find CHAP_N.\n");
+		goto out;
+	}
+
+	/* Include the terminating NULL in the compare */
+	compare_len = strlen(auth->userid) + 1;
+	if (strncmp(chap_n, auth->userid, compare_len) != 0) {
+		pr_err("CHAP_N values do not match!\n");
+		goto out;
+	}
+	pr_debug("[server] Got CHAP_N=%s\n", chap_n);
+	/*
+	 * Extract CHAP_R.
+	 */
+	if (extract_param(nr_in_ptr, "CHAP_R", MAX_RESPONSE_LENGTH, chap_r,
+				&type) < 0) {
+		pr_err("Could not find CHAP_R.\n");
+		goto out;
+	}
+
+	switch (type) {
+	case HEX:
+		if (strlen(chap_r) != chap->digest_size * 2) {
+			pr_err("Malformed CHAP_R\n");
+			goto out;
+		}
+		if (hex2bin(client_digest, chap_r, chap->digest_size) < 0) {
+			pr_err("Malformed CHAP_R: invalid HEX\n");
+			goto out;
+		}
+		break;
+	case BASE64:
+		if (chap_base64_decode(client_digest, chap_r, strlen(chap_r)) !=
+		    chap->digest_size) {
+			pr_err("Malformed CHAP_R: invalid BASE64\n");
+			goto out;
+		}
+		break;
+	default:
+		pr_err("Could not find CHAP_R\n");
+		goto out;
+	}
+
+	pr_debug("[server] Got CHAP_R=%s\n", chap_r);
+
+	tfm = crypto_alloc_shash(chap->digest_name, 0, 0);
+	if (IS_ERR(tfm)) {
+		tfm = NULL;
+		pr_err("Unable to allocate struct crypto_shash\n");
+		goto out;
+	}
+
+	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(tfm), GFP_KERNEL);
+	if (!desc) {
+		pr_err("Unable to allocate struct shash_desc\n");
+		goto out;
+	}
+
+	desc->tfm = tfm;
+
+	ret = crypto_shash_init(desc);
+	if (ret < 0) {
+		pr_err("crypto_shash_init() failed\n");
+		goto out;
+	}
+
+	ret = crypto_shash_update(desc, &chap->id, 1);
+	if (ret < 0) {
+		pr_err("crypto_shash_update() failed for id\n");
+		goto out;
+	}
+
+	ret = crypto_shash_update(desc, (char *)&auth->password,
+				  strlen(auth->password));
+	if (ret < 0) {
+		pr_err("crypto_shash_update() failed for password\n");
+		goto out;
+	}
+
+	ret = crypto_shash_finup(desc, chap->challenge,
+				 chap->challenge_len, server_digest);
+	if (ret < 0) {
+		pr_err("crypto_shash_finup() failed for challenge\n");
+		goto out;
+	}
+
+	bin2hex(response, server_digest, chap->digest_size);
+	pr_debug("[server] %s Server Digest: %s\n",
+		chap->digest_name, response);
+
+	if (memcmp(server_digest, client_digest, chap->digest_size) != 0) {
+		pr_debug("[server] %s Digests do not match!\n\n",
+			chap->digest_name);
+		goto out;
+	} else
+		pr_debug("[server] %s Digests match, CHAP connection"
+				" successful.\n\n", chap->digest_name);
+	/*
+	 * One way authentication has succeeded, return now if mutual
+	 * authentication is not enabled.
+	 */
+	if (!auth->authenticate_target) {
+		auth_ret = 0;
+		goto out;
+	}
+	/*
+	 * Get CHAP_I.
+	 */
+	ret = extract_param(nr_in_ptr, "CHAP_I", 10, identifier, &type);
+	if (ret == -ENOENT) {
+		pr_debug("Could not find CHAP_I. Initiator uses One way authentication.\n");
+		auth_ret = 0;
+		goto out;
+	}
+	if (ret < 0) {
+		pr_err("Could not find CHAP_I.\n");
+		goto out;
+	}
+
+	if (type == HEX)
+		ret = kstrtoul(&identifier[2], 0, &id);
+	else
+		ret = kstrtoul(identifier, 0, &id);
+
+	if (ret < 0) {
+		pr_err("kstrtoul() failed for CHAP identifier: %d\n", ret);
+		goto out;
+	}
+	if (id > 255) {
+		pr_err("chap identifier: %lu greater than 255\n", id);
+		goto out;
+	}
+	/*
+	 * RFC 1994 says Identifier is no more than octet (8 bits).
+	 */
+	pr_debug("[server] Got CHAP_I=%lu\n", id);
+	/*
+	 * Get CHAP_C.
+	 */
+	if (extract_param(nr_in_ptr, "CHAP_C", CHAP_CHALLENGE_STR_LEN,
+			initiatorchg, &type) < 0) {
+		pr_err("Could not find CHAP_C.\n");
+		goto out;
+	}
+
+	switch (type) {
+	case HEX:
+		initiatorchg_len = DIV_ROUND_UP(strlen(initiatorchg), 2);
+		if (!initiatorchg_len) {
+			pr_err("Unable to convert incoming challenge\n");
+			goto out;
+		}
+		if (initiatorchg_len > 1024) {
+			pr_err("CHAP_C exceeds maximum binary size of 1024 bytes\n");
+			goto out;
+		}
+
+		if (hex2bin(initiatorchg_binhex, initiatorchg,
+			    initiatorchg_len) < 0) {
+			pr_err("Malformed CHAP_C: invalid HEX\n");
+			goto out;
+		}
+		break;
+	case BASE64:
+		initiatorchg_len = chap_base64_decode(initiatorchg_binhex,
+						      initiatorchg,
+						      strlen(initiatorchg));
+		if (initiatorchg_len < 0) {
+			pr_err("Malformed CHAP_C: invalid BASE64\n");
+			goto out;
+		}
+		if (!initiatorchg_len) {
+			pr_err("Unable to convert incoming challenge\n");
+			goto out;
+		}
+		if (initiatorchg_len > 1024) {
+			pr_err("CHAP_C exceeds maximum binary size of 1024 bytes\n");
+			goto out;
+		}
+		break;
+	default:
+		pr_err("Could not find CHAP_C.\n");
+		goto out;
+	}
+
+	pr_debug("[server] Got CHAP_C=%s\n", initiatorchg);
+	/*
+	 * During mutual authentication, the CHAP_C generated by the
+	 * initiator must not match the original CHAP_C generated by
+	 * the target.
+	 */
+	if (initiatorchg_len == chap->challenge_len &&
+				!memcmp(initiatorchg_binhex, chap->challenge,
+				initiatorchg_len)) {
+		pr_err("initiator CHAP_C matches target CHAP_C, failing"
+		       " login attempt\n");
+		goto out;
+	}
+	/*
+	 * Generate CHAP_N and CHAP_R for mutual authentication.
+	 */
+	ret = crypto_shash_init(desc);
+	if (ret < 0) {
+		pr_err("crypto_shash_init() failed\n");
+		goto out;
+	}
+
+	/* To handle both endiannesses */
+	id_as_uchar = id;
+	ret = crypto_shash_update(desc, &id_as_uchar, 1);
+	if (ret < 0) {
+		pr_err("crypto_shash_update() failed for id\n");
+		goto out;
+	}
+
+	ret = crypto_shash_update(desc, auth->password_mutual,
+				  strlen(auth->password_mutual));
+	if (ret < 0) {
+		pr_err("crypto_shash_update() failed for"
+				" password_mutual\n");
+		goto out;
+	}
+	/*
+	 * Convert received challenge to binary hex.
+	 */
+	ret = crypto_shash_finup(desc, initiatorchg_binhex, initiatorchg_len,
+				 digest);
+	if (ret < 0) {
+		pr_err("crypto_shash_finup() failed for ma challenge\n");
+		goto out;
+	}
+
+	/*
+	 * Generate CHAP_N and CHAP_R.
+	 */
+	*nr_out_len = sprintf(nr_out_ptr, "CHAP_N=%s", auth->userid_mutual);
+	*nr_out_len += 1;
+	pr_debug("[server] Sending CHAP_N=%s\n", auth->userid_mutual);
+	/*
+	 * Convert response from binary hex to ascii hext.
+	 */
+	bin2hex(response, digest, chap->digest_size);
+	*nr_out_len += sprintf(nr_out_ptr + *nr_out_len, "CHAP_R=0x%s",
+			response);
+	*nr_out_len += 1;
+	pr_debug("[server] Sending CHAP_R=0x%s\n", response);
+	auth_ret = 0;
+out:
+	kfree_sensitive(desc);
+	if (tfm)
+		crypto_free_shash(tfm);
+	kfree(initiatorchg);
+	kfree(initiatorchg_binhex);
+	kfree(digest);
+	kfree(response);
+	kfree(server_digest);
+	kfree(client_digest);
+	return auth_ret;
+}
+
+u32 chap_main_loop(
+	struct iscsit_conn *conn,
+	struct iscsi_node_auth *auth,
+	char *in_text,
+	char *out_text,
+	int *in_len,
+	int *out_len)
+{
+	struct iscsi_chap *chap = conn->auth_protocol;
+
+	if (!chap) {
+		chap = chap_server_open(conn, auth, in_text, out_text, out_len);
+		if (!chap)
+			return 2;
+		chap->chap_state = CHAP_STAGE_SERVER_AIC;
+		return 0;
+	} else if (chap->chap_state == CHAP_STAGE_SERVER_AIC) {
+		convert_null_to_semi(in_text, *in_len);
+		if (chap_server_compute_hash(conn, auth, in_text, out_text,
+				out_len) < 0) {
+			chap_close(conn);
+			return 2;
+		}
+		if (auth->authenticate_target)
+			chap->chap_state = CHAP_STAGE_SERVER_NR;
+		else
+			*out_len = 0;
+		chap_close(conn);
+		return 1;
+	}
+
+	return 2;
+}