Re: [PATCH 07/12] nvme: Implement In-Band authentication

Sagi Grimberg
2021-11-16T10:26:08Z

On 11/12/21 2:59 PM, Hannes Reinecke wrote:
> Implement NVMe-oF In-Band authentication according to NVMe TPAR 8006.
> This patch adds two new fabric options 'dhchap_secret' to specify the
> pre-shared key (in ASCII respresentation according to NVMe 2.0 section
> 8.13.5.8 'Secret representation') and 'dhchap_ctrl_secret' to specify
> the pre-shared controller key for bi-directional authentication of both
> the host and the controller.
> Re-authentication can be triggered by writing the PSK into the new
> controller sysfs attribute 'dhchap_secret' or 'dhchap_ctrl_secret'.
>
> Signed-off-by: Hannes Reinecke <hare@suse.de>
> ---
> drivers/nvme/host/Kconfig | 11 +
> drivers/nvme/host/Makefile | 1 +
> drivers/nvme/host/auth.c | 1164 +++++++++++++++++++++++++++++++++++
> drivers/nvme/host/auth.h | 25 +
> drivers/nvme/host/core.c | 133 +++-
> drivers/nvme/host/fabrics.c | 79 ++-
> drivers/nvme/host/fabrics.h | 7 +
> drivers/nvme/host/nvme.h | 36 ++
> drivers/nvme/host/tcp.c | 1 +
> drivers/nvme/host/trace.c | 32 +
> 10 files changed, 1482 insertions(+), 7 deletions(-)
> create mode 100644 drivers/nvme/host/auth.c
> create mode 100644 drivers/nvme/host/auth.h
>
> diff --git a/drivers/nvme/host/Kconfig b/drivers/nvme/host/Kconfig
> index dc0450ca23a3..49269c581ec4 100644
> --- a/drivers/nvme/host/Kconfig
> +++ b/drivers/nvme/host/Kconfig
> @@ -83,3 +83,14 @@ config NVME_TCP
> from https://github.com/linux-nvme/nvme-cli.
>
> If unsure, say N.
> +
> +config NVME_AUTH
> + bool "NVM Express over Fabrics In-Band Authentication"
> + depends on NVME_CORE
> + select CRYPTO_HMAC
> + select CRYPTO_SHA256
> + select CRYPTO_SHA512
> + help
> + This provides support for NVMe over Fabrics In-Band Authentication.
> +
> + If unsure, say N.
> diff --git a/drivers/nvme/host/Makefile b/drivers/nvme/host/Makefile
> index dfaacd472e5d..4bae2a4a8d8c 100644
> --- a/drivers/nvme/host/Makefile
> +++ b/drivers/nvme/host/Makefile
> @@ -15,6 +15,7 @@ nvme-core-$(CONFIG_NVME_MULTIPATH) += multipath.o
> nvme-core-$(CONFIG_BLK_DEV_ZONED) += zns.o
> nvme-core-$(CONFIG_FAULT_INJECTION_DEBUG_FS) += fault_inject.o
> nvme-core-$(CONFIG_NVME_HWMON) += hwmon.o
> +nvme-core-$(CONFIG_NVME_AUTH) += auth.o
>
> nvme-y += pci.o
>
> diff --git a/drivers/nvme/host/auth.c b/drivers/nvme/host/auth.c
> new file mode 100644
> index 000000000000..6ab95a178213
> --- /dev/null
> +++ b/drivers/nvme/host/auth.c
> @@ -0,0 +1,1164 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2020 Hannes Reinecke, SUSE Linux
> + */
> +
> +#include <linux/crc32.h>
> +#include <linux/base64.h>
> +#include <asm/unaligned.h>
> +#include <crypto/hash.h>
> +#include <crypto/dh.h>
> +#include <crypto/ffdhe.h>
> +#include "nvme.h"
> +#include "fabrics.h"
> +#include "auth.h"
> +
> +static atomic_t nvme_dhchap_seqnum = ATOMIC_INIT(0);
> +
> +struct nvme_dhchap_queue_context {
> + struct list_head entry;
> + struct work_struct auth_work;
> + struct nvme_ctrl *ctrl;
> + struct crypto_shash *shash_tfm;
> + void *buf;
> + size_t buf_size;
> + int qid;
> + int error;
> + u32 s1;
> + u32 s2;
> + u16 transaction;
> + u8 status;
> + u8 hash_id;
> + u8 hash_len;
> + u8 dhgroup_id;
> + u8 c1[64];
> + u8 c2[64];
> + u8 response[64];
> + u8 *host_response;
> +};
> +
> +static struct nvme_auth_dhgroup_map {
> + int id;
> + const char name[16];
> + const char kpp[16];
> + int privkey_size;
> + int pubkey_size;
> +} dhgroup_map[] = {
> + { .id = NVME_AUTH_DHCHAP_DHGROUP_NULL,
> + .name = "null", .kpp = "null",
> + .privkey_size = 0, .pubkey_size = 0 },
> + { .id = NVME_AUTH_DHCHAP_DHGROUP_2048,
> + .name = "ffdhe2048", .kpp = "dh",
> + .privkey_size = 256, .pubkey_size = 256 },
> + { .id = NVME_AUTH_DHCHAP_DHGROUP_3072,
> + .name = "ffdhe3072", .kpp = "dh",
> + .privkey_size = 384, .pubkey_size = 384 },
> + { .id = NVME_AUTH_DHCHAP_DHGROUP_4096,
> + .name = "ffdhe4096", .kpp = "dh",
> + .privkey_size = 512, .pubkey_size = 512 },
> + { .id = NVME_AUTH_DHCHAP_DHGROUP_6144,
> + .name = "ffdhe6144", .kpp = "dh",
> + .privkey_size = 768, .pubkey_size = 768 },
> + { .id = NVME_AUTH_DHCHAP_DHGROUP_8192,
> + .name = "ffdhe8192", .kpp = "dh",
> + .privkey_size = 1024, .pubkey_size = 1024 },
> +};
> +
> +const char *nvme_auth_dhgroup_name(int dhgroup_id)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(dhgroup_map); i++) {
> + if (dhgroup_map[i].id == dhgroup_id)
> + return dhgroup_map[i].name;
> + }
> + return NULL;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_name);
> +
> +int nvme_auth_dhgroup_pubkey_size(int dhgroup_id)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(dhgroup_map); i++) {
> + if (dhgroup_map[i].id == dhgroup_id)
> + return dhgroup_map[i].pubkey_size;
> + }
> + return -1;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_pubkey_size);
> +
> +int nvme_auth_dhgroup_privkey_size(int dhgroup_id)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(dhgroup_map); i++) {
> + if (dhgroup_map[i].id == dhgroup_id)
> + return dhgroup_map[i].privkey_size;
> + }
> + return -1;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_privkey_size);
> +
> +const char *nvme_auth_dhgroup_kpp(int dhgroup_id)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(dhgroup_map); i++) {
> + if (dhgroup_map[i].id == dhgroup_id)
> + return dhgroup_map[i].kpp;
> + }
> + return NULL;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_kpp);
> +
> +int nvme_auth_dhgroup_id(const char *dhgroup_name)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(dhgroup_map); i++) {
> + if (!strncmp(dhgroup_map[i].name, dhgroup_name,
> + strlen(dhgroup_map[i].name)))
> + return dhgroup_map[i].id;
> + }
> + return -1;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_dhgroup_id);
> +
> +static struct nvme_dhchap_hash_map {
> + int id;
> + int len;
> + const char hmac[15];
> + const char digest[15];
> +} hash_map[] = {
> + {.id = NVME_AUTH_DHCHAP_SHA256, .len = 32,
> + .hmac = "hmac(sha256)", .digest = "sha256" },
> + {.id = NVME_AUTH_DHCHAP_SHA384, .len = 48,
> + .hmac = "hmac(sha384)", .digest = "sha384" },
> + {.id = NVME_AUTH_DHCHAP_SHA512, .len = 64,
> + .hmac = "hmac(sha512)", .digest = "sha512" },
> +};
> +
> +const char *nvme_auth_hmac_name(int hmac_id)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(hash_map); i++) {
> + if (hash_map[i].id == hmac_id)
> + return hash_map[i].hmac;
> + }
> + return NULL;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_hmac_name);
> +
> +const char *nvme_auth_digest_name(int hmac_id)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(hash_map); i++) {
> + if (hash_map[i].id == hmac_id)
> + return hash_map[i].digest;
> + }
> + return NULL;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_digest_name);
> +
> +int nvme_auth_hmac_id(const char *hmac_name)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(hash_map); i++) {
> + if (!strncmp(hash_map[i].hmac, hmac_name,
> + strlen(hash_map[i].hmac)))
> + return hash_map[i].id;
> + }
> + return -1;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_hmac_id);
> +
> +int nvme_auth_hmac_hash_len(int hmac_id)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(hash_map); i++) {
> + if (hash_map[i].id == hmac_id)
> + return hash_map[i].len;
> + }
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_hmac_hash_len);
> +
> +unsigned char *nvme_auth_extract_secret(unsigned char *secret, u8 key_hash,
> + size_t *out_len)
> +{
> + unsigned char *key, *p;
> + u32 crc;
> + int key_len;
> + size_t allocated_len = strlen(secret);
> +
> + /* Secret might be affixed with a ':' */
> + p = strrchr(secret, ':');
> + if (p)
> + allocated_len = p - secret;
> + key = kzalloc(allocated_len, GFP_KERNEL);
> + if (!key)
> + return ERR_PTR(-ENOMEM);
> +
> + key_len = base64_decode(secret, allocated_len, key);
> + if (key_len < 0) {
> + pr_debug("base64 key decoding error %d\n",
> + key_len);
> + return ERR_PTR(key_len);
> + }
> + if (key_len != 36 && key_len != 52 &&
> + key_len != 68) {
> + pr_debug("Invalid key len %d\n",
> + key_len);

pr_err?

> + kfree_sensitive(key);
> + return ERR_PTR(-EINVAL);
> + }
> + if (key_hash > 0 &&
> + (key_len - 4) != nvme_auth_hmac_hash_len(key_hash)) {
> + pr_debug("Invalid key len %d for %s\n", key_len,
> + nvme_auth_hmac_name(key_hash));

pr_err?

> + kfree_sensitive(key);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + /* The last four bytes is the CRC in little-endian format */
> + key_len -= 4;
> + /*
> + * The linux implementation doesn't do pre- and post-increments,
> + * so we have to do it manually.
> + */
> + crc = ~crc32(~0, key, key_len);
> +
> + if (get_unaligned_le32(key + key_len) != crc) {
> + pr_debug("DH-HMAC-CHAP key crc mismatch (key %08x, crc %08x)\n",
> + get_unaligned_le32(key + key_len), crc);

pr_err?

> + kfree_sensitive(key);
> + return ERR_PTR(-EKEYREJECTED);
> + }
> + *out_len = key_len;
> + return key;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_extract_secret);
> +
> +u8 *nvme_auth_transform_key(u8 *key, size_t key_len, u8 key_hash, char *nqn)
> +{
> + const char *hmac_name = nvme_auth_hmac_name(key_hash);
> + struct crypto_shash *key_tfm;
> + struct shash_desc *shash;
> + u8 *transformed_key;
> + int ret;
> +
> + if (key_hash == 0) {
> + transformed_key = kmemdup(key, key_len, GFP_KERNEL);
> + return transformed_key ? transformed_key : ERR_PTR(-ENOMEM);
> + }
> +
> + if (!key || !key_len) {
> + pr_warn("No key specified\n");

pr_err?

> + return ERR_PTR(-ENOKEY);
> + }
> + if (!hmac_name) {
> + pr_warn("Invalid key hash id %d\n", key_hash);

pr_err?

> + return ERR_PTR(-EINVAL);
> + }
> +
> + key_tfm = crypto_alloc_shash(hmac_name, 0, 0);
> + if (IS_ERR(key_tfm))
> + return (u8 *)key_tfm;
> +
> + shash = kmalloc(sizeof(struct shash_desc) +
> + crypto_shash_descsize(key_tfm),
> + GFP_KERNEL);
> + if (!shash) {
> + ret = -ENOMEM;
> + goto out_free_key;
> + }
> +
> + transformed_key = kzalloc(crypto_shash_digestsize(key_tfm), GFP_KERNEL);
> + if (!transformed_key) {
> + ret = -ENOMEM;
> + goto out_free_shash;
> + }
> +
> + shash->tfm = key_tfm;
> + ret = crypto_shash_setkey(key_tfm, key, key_len);
> + if (ret < 0)
> + goto out_free_shash;
> + ret = crypto_shash_init(shash);
> + if (ret < 0)
> + goto out_free_shash;
> + ret = crypto_shash_update(shash, nqn, strlen(nqn));
> + if (ret < 0)
> + goto out_free_shash;
> + ret = crypto_shash_update(shash, "NVMe-over-Fabrics", 17);
> + if (ret < 0)
> + goto out_free_shash;
> + ret = crypto_shash_final(shash, transformed_key);
> +out_free_shash:
> + kfree(shash);
> +out_free_key:
> + crypto_free_shash(key_tfm);
> + if (ret < 0) {
> + kfree_sensitive(transformed_key);
> + return ERR_PTR(ret);
> + }
> + return transformed_key;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_transform_key);
> +
> +static int nvme_auth_send(struct nvme_ctrl *ctrl, int qid,
> + void *data, size_t tl)
> +{
> + struct nvme_command cmd = {};
> + blk_mq_req_flags_t flags = qid == NVME_QID_ANY ?
> + 0 : BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED;
> + struct request_queue *q = qid == NVME_QID_ANY ?
> + ctrl->fabrics_q : ctrl->connect_q;
> + int ret;
> +
> + cmd.auth_send.opcode = nvme_fabrics_command;
> + cmd.auth_send.fctype = nvme_fabrics_type_auth_send;
> + cmd.auth_send.secp = NVME_AUTH_DHCHAP_PROTOCOL_IDENTIFIER;
> + cmd.auth_send.spsp0 = 0x01;
> + cmd.auth_send.spsp1 = 0x01;
> + cmd.auth_send.tl = cpu_to_le32(tl);
> +
> + ret = __nvme_submit_sync_cmd(q, &cmd, NULL, data, tl, 0, qid,
> + 0, flags);
> + if (ret > 0)
> + dev_dbg(ctrl->device,
> + "%s: qid %d nvme status %d\n", __func__, qid, ret);

dev_err? Also can we phrase "failed auth_send" instead of the __func__?

> + else if (ret < 0)
> + dev_dbg(ctrl->device,
> + "%s: qid %d error %d\n", __func__, qid, ret);

dev_err?

> + return ret;
> +}
> +
> +static int nvme_auth_receive(struct nvme_ctrl *ctrl, int qid,
> + void *buf, size_t al)
> +{
> + struct nvme_command cmd = {};
> + blk_mq_req_flags_t flags = qid == NVME_QID_ANY ?
> + 0 : BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED;
> + struct request_queue *q = qid == NVME_QID_ANY ?
> + ctrl->fabrics_q : ctrl->connect_q;
> + int ret;
> +
> + cmd.auth_receive.opcode = nvme_fabrics_command;
> + cmd.auth_receive.fctype = nvme_fabrics_type_auth_receive;
> + cmd.auth_receive.secp = NVME_AUTH_DHCHAP_PROTOCOL_IDENTIFIER;
> + cmd.auth_receive.spsp0 = 0x01;
> + cmd.auth_receive.spsp1 = 0x01;
> + cmd.auth_receive.al = cpu_to_le32(al);
> +
> + ret = __nvme_submit_sync_cmd(q, &cmd, NULL, buf, al, 0, qid,
> + 0, flags);
> + if (ret > 0) {
> + dev_dbg(ctrl->device, "%s: qid %d nvme status %x\n",
> + __func__, qid, ret);

dev_err? "failed auth_recv" instead of the __func__

> + ret = -EIO;
> + }
> + if (ret < 0) {
> + dev_dbg(ctrl->device, "%s: qid %d error %d\n",
> + __func__, qid, ret);

dev_err

> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int nvme_auth_receive_validate(struct nvme_ctrl *ctrl, int qid,
> + struct nvmf_auth_dhchap_failure_data *data,
> + u16 transaction, u8 expected_msg)
> +{
> + dev_dbg(ctrl->device, "%s: qid %d auth_type %d auth_id %x\n",
> + __func__, qid, data->auth_type, data->auth_id);
> +
> + if (data->auth_type == NVME_AUTH_COMMON_MESSAGES &&
> + data->auth_id == NVME_AUTH_DHCHAP_MESSAGE_FAILURE1) {
> + return data->rescode_exp;
> + }
> + if (data->auth_type != NVME_AUTH_DHCHAP_MESSAGES ||
> + data->auth_id != expected_msg) {
> + dev_warn(ctrl->device,
> + "qid %d invalid message %02x/%02x\n",
> + qid, data->auth_type, data->auth_id);
> + return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_MESSAGE;
> + }
> + if (le16_to_cpu(data->t_id) != transaction) {
> + dev_warn(ctrl->device,
> + "qid %d invalid transaction ID %d\n",
> + qid, le16_to_cpu(data->t_id));

why not dev_err?

> + return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_MESSAGE;
> + }
> + return 0;
> +}
> +
> +static int nvme_auth_set_dhchap_negotiate_data(struct nvme_ctrl *ctrl,
> + struct nvme_dhchap_queue_context *chap)
> +{
> + struct nvmf_auth_dhchap_negotiate_data *data = chap->buf;
> + size_t size = sizeof(*data) + sizeof(union nvmf_auth_protocol);
> +
> + if (chap->buf_size < size) {
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
> + return -EINVAL;
> + }
> + memset((u8 *)chap->buf, 0, size);
> + data->auth_type = NVME_AUTH_COMMON_MESSAGES;
> + data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_NEGOTIATE;
> + data->t_id = cpu_to_le16(chap->transaction);
> + data->sc_c = 0; /* No secure channel concatenation */
> + data->napd = 1;
> + data->auth_protocol[0].dhchap.authid = NVME_AUTH_DHCHAP_AUTH_ID;
> + data->auth_protocol[0].dhchap.halen = 3;
> + data->auth_protocol[0].dhchap.dhlen = 6;
> + data->auth_protocol[0].dhchap.idlist[0] = NVME_AUTH_DHCHAP_SHA256;
> + data->auth_protocol[0].dhchap.idlist[1] = NVME_AUTH_DHCHAP_SHA384;
> + data->auth_protocol[0].dhchap.idlist[2] = NVME_AUTH_DHCHAP_SHA512;
> + data->auth_protocol[0].dhchap.idlist[3] = NVME_AUTH_DHCHAP_DHGROUP_NULL;
> + data->auth_protocol[0].dhchap.idlist[4] = NVME_AUTH_DHCHAP_DHGROUP_2048;
> + data->auth_protocol[0].dhchap.idlist[5] = NVME_AUTH_DHCHAP_DHGROUP_3072;
> + data->auth_protocol[0].dhchap.idlist[6] = NVME_AUTH_DHCHAP_DHGROUP_4096;
> + data->auth_protocol[0].dhchap.idlist[7] = NVME_AUTH_DHCHAP_DHGROUP_6144;
> + data->auth_protocol[0].dhchap.idlist[8] = NVME_AUTH_DHCHAP_DHGROUP_8192;
> +
> + return size;
> +}
> +
> +static int nvme_auth_process_dhchap_challenge(struct nvme_ctrl *ctrl,
> + struct nvme_dhchap_queue_context *chap)
> +{
> + struct nvmf_auth_dhchap_challenge_data *data = chap->buf;
> + u16 dhvlen = le16_to_cpu(data->dhvlen);
> + size_t size = sizeof(*data) + data->hl + dhvlen;
> + const char *hmac_name, *kpp_name;
> +
> + if (chap->buf_size < size) {
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
> + return NVME_SC_INVALID_FIELD;
> + }
> +
> + hmac_name = nvme_auth_hmac_name(data->hashid);
> + if (!hmac_name) {
> + dev_warn(ctrl->device,
> + "qid %d: invalid HASH ID %d\n",
> + chap->qid, data->hashid);
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
> + return NVME_SC_INVALID_FIELD;
> + }
> +
> + if (chap->hash_id == data->hashid && chap->shash_tfm &&
> + !strcmp(crypto_shash_alg_name(chap->shash_tfm), hmac_name) &&
> + crypto_shash_digestsize(chap->shash_tfm) == data->hl) {
> + dev_dbg(ctrl->device,
> + "qid %d: reuse existing hash %s\n",
> + chap->qid, hmac_name);
> + goto select_kpp;
> + }
> +
> + /* Reset if hash cannot be reused */
> + if (chap->shash_tfm) {
> + crypto_free_shash(chap->shash_tfm);
> + chap->hash_id = 0;
> + chap->hash_len = 0;
> + }
> + chap->shash_tfm = crypto_alloc_shash(hmac_name, 0,
> + CRYPTO_ALG_ALLOCATES_MEMORY);
> + if (IS_ERR(chap->shash_tfm)) {
> + dev_warn(ctrl->device,
> + "qid %d: failed to allocate hash %s, error %ld\n",
> + chap->qid, hmac_name, PTR_ERR(chap->shash_tfm));
> + chap->shash_tfm = NULL;
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
> + return NVME_SC_AUTH_REQUIRED;
> + }
> +
> + if (crypto_shash_digestsize(chap->shash_tfm) != data->hl) {
> + dev_warn(ctrl->device,
> + "qid %d: invalid hash length %d\n",
> + chap->qid, data->hl);
> + crypto_free_shash(chap->shash_tfm);
> + chap->shash_tfm = NULL;
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
> + return NVME_SC_AUTH_REQUIRED;
> + }
> +
> + /* Reset host response if the hash had been changed */
> + if (chap->hash_id != data->hashid) {
> + kfree(chap->host_response);
> + chap->host_response = NULL;
> + }
> +
> + chap->hash_id = data->hashid;
> + chap->hash_len = data->hl;
> + dev_dbg(ctrl->device, "qid %d: selected hash %s\n",
> + chap->qid, hmac_name);
> +
> +select_kpp:
> + kpp_name = nvme_auth_dhgroup_kpp(data->dhgid);
> + if (!kpp_name) {
> + dev_warn(ctrl->device,
> + "qid %d: invalid DH group id %d\n",
> + chap->qid, data->dhgid);
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
> + return NVME_SC_AUTH_REQUIRED;
> + }
> +
> + if (data->dhgid != NVME_AUTH_DHCHAP_DHGROUP_NULL) {
> + dev_warn(ctrl->device,
> + "qid %d: unsupported DH group %s\n",
> + chap->qid, kpp_name);
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
> + return NVME_SC_AUTH_REQUIRED;
> + } else if (dhvlen != 0) {
> + dev_warn(ctrl->device,
> + "qid %d: invalid DH value for NULL DH\n",
> + chap->qid);
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
> + return NVME_SC_INVALID_FIELD;
> + }
> + chap->dhgroup_id = data->dhgid;
> +
> + chap->s1 = le32_to_cpu(data->seqnum);
> + memcpy(chap->c1, data->cval, chap->hash_len);
> +
> + return 0;
> +}
> +
> +static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
> + struct nvme_dhchap_queue_context *chap)
> +{
> + struct nvmf_auth_dhchap_reply_data *data = chap->buf;
> + size_t size = sizeof(*data);
> +
> + size += 2 * chap->hash_len;
> +
> + if (chap->buf_size < size) {
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
> + return -EINVAL;
> + }
> +
> + memset(chap->buf, 0, size);
> + data->auth_type = NVME_AUTH_DHCHAP_MESSAGES;
> + data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_REPLY;
> + data->t_id = cpu_to_le16(chap->transaction);
> + data->hl = chap->hash_len;
> + data->dhvlen = 0;
> + memcpy(data->rval, chap->response, chap->hash_len);
> + if (ctrl->opts->dhchap_ctrl_secret) {
> + get_random_bytes(chap->c2, chap->hash_len);
> + data->cvalid = 1;
> + chap->s2 = atomic_inc_return(&nvme_dhchap_seqnum);
> + memcpy(data->rval + chap->hash_len, chap->c2,
> + chap->hash_len);
> + dev_dbg(ctrl->device, "%s: qid %d ctrl challenge %*ph\n",
> + __func__, chap->qid,
> + chap->hash_len, chap->c2);
> + } else {
> + memset(chap->c2, 0, chap->hash_len);
> + chap->s2 = 0;
> + }
> + data->seqnum = cpu_to_le32(chap->s2);
> + return size;
> +}
> +
> +static int nvme_auth_process_dhchap_success1(struct nvme_ctrl *ctrl,
> + struct nvme_dhchap_queue_context *chap)
> +{
> + struct nvmf_auth_dhchap_success1_data *data = chap->buf;
> + size_t size = sizeof(*data);
> +
> + if (ctrl->opts->dhchap_ctrl_secret)
> + size += chap->hash_len;
> +
> + if (chap->buf_size < size) {
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
> + return NVME_SC_INVALID_FIELD;
> + }
> +
> + if (data->hl != chap->hash_len) {
> + dev_warn(ctrl->device,
> + "qid %d: invalid hash length %d\n",
> + chap->qid, data->hl);
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
> + return NVME_SC_INVALID_FIELD;
> + }
> +
> + /* Just print out information for the admin queue */
> + if (chap->qid == -1)
> + dev_info(ctrl->device,
> + "qid 0: authenticated with hash %s dhgroup %s\n",
> + nvme_auth_hmac_name(chap->hash_id),
> + nvme_auth_dhgroup_name(chap->dhgroup_id));
> +
> + if (!data->rvalid)
> + return 0;
> +
> + /* Validate controller response */
> + if (memcmp(chap->response, data->rval, data->hl)) {
> + dev_dbg(ctrl->device, "%s: qid %d ctrl response %*ph\n",
> + __func__, chap->qid, chap->hash_len, data->rval);
> + dev_dbg(ctrl->device, "%s: qid %d host response %*ph\n",
> + __func__, chap->qid, chap->hash_len, chap->response);
> + dev_warn(ctrl->device,
> + "qid %d: controller authentication failed\n",
> + chap->qid);
> + chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
> + return NVME_SC_AUTH_REQUIRED;
> + }
> +
> + /* Just print out information for the admin queue */
> + if (chap->qid == -1)
> + dev_info(ctrl->device,
> + "qid 0: controller authenticated\n");
> + return 0;
> +}
> +
> +static int nvme_auth_set_dhchap_success2_data(struct nvme_ctrl *ctrl,
> + struct nvme_dhchap_queue_context *chap)
> +{
> + struct nvmf_auth_dhchap_success2_data *data = chap->buf;
> + size_t size = sizeof(*data);
> +
> + memset(chap->buf, 0, size);
> + data->auth_type = NVME_AUTH_DHCHAP_MESSAGES;
> + data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_SUCCESS2;
> + data->t_id = cpu_to_le16(chap->transaction);
> +
> + return size;
> +}
> +
> +static int nvme_auth_set_dhchap_failure2_data(struct nvme_ctrl *ctrl,
> + struct nvme_dhchap_queue_context *chap)
> +{
> + struct nvmf_auth_dhchap_failure_data *data = chap->buf;
> + size_t size = sizeof(*data);
> +
> + memset(chap->buf, 0, size);
> + data->auth_type = NVME_AUTH_DHCHAP_MESSAGES;
> + data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_FAILURE2;
> + data->t_id = cpu_to_le16(chap->transaction);
> + data->rescode = NVME_AUTH_DHCHAP_FAILURE_REASON_FAILED;
> + data->rescode_exp = chap->status;
> +
> + return size;
> +}
> +
> +static int nvme_auth_dhchap_host_response(struct nvme_ctrl *ctrl,
> + struct nvme_dhchap_queue_context *chap)
> +{
> + SHASH_DESC_ON_STACK(shash, chap->shash_tfm);
> + u8 buf[4], *challenge = chap->c1;
> + int ret;
> +
> + dev_dbg(ctrl->device, "%s: qid %d host response seq %d transaction %d\n",
> + __func__, chap->qid, chap->s1, chap->transaction);
> +
> + if (!chap->host_response) {
> + chap->host_response = nvme_auth_transform_key(ctrl->dhchap_key,
> + ctrl->dhchap_key_len,
> + ctrl->dhchap_key_hash,
> + ctrl->opts->host->nqn);
> + if (IS_ERR(chap->host_response)) {
> + ret = PTR_ERR(chap->host_response);
> + chap->host_response = NULL;
> + return ret;
> + }
> + } else {
> + dev_dbg(ctrl->device, "%s: qid %d re-using host response\n",
> + __func__, chap->qid);
> + }
> +
> + ret = crypto_shash_setkey(chap->shash_tfm,
> + chap->host_response, ctrl->dhchap_key_len);
> + if (ret) {
> + dev_warn(ctrl->device, "qid %d: failed to set key, error %d\n",
> + chap->qid, ret);
> + goto out;
> + }
> +
> + shash->tfm = chap->shash_tfm;
> + ret = crypto_shash_init(shash);
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, challenge, chap->hash_len);
> + if (ret)
> + goto out;
> + put_unaligned_le32(chap->s1, buf);
> + ret = crypto_shash_update(shash, buf, 4);
> + if (ret)
> + goto out;
> + put_unaligned_le16(chap->transaction, buf);
> + ret = crypto_shash_update(shash, buf, 2);
> + if (ret)
> + goto out;
> + memset(buf, 0, sizeof(buf));
> + ret = crypto_shash_update(shash, buf, 1);
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, "HostHost", 8);
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, ctrl->opts->host->nqn,
> + strlen(ctrl->opts->host->nqn));
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, buf, 1);
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, ctrl->opts->subsysnqn,
> + strlen(ctrl->opts->subsysnqn));
> + if (ret)
> + goto out;
> + ret = crypto_shash_final(shash, chap->response);
> +out:
> + if (challenge != chap->c1)
> + kfree(challenge);
> + return ret;
> +}
> +
> +static int nvme_auth_dhchap_ctrl_response(struct nvme_ctrl *ctrl,
> + struct nvme_dhchap_queue_context *chap)
> +{
> + SHASH_DESC_ON_STACK(shash, chap->shash_tfm);
> + u8 *ctrl_response;
> + u8 buf[4], *challenge = chap->c2;
> + int ret;
> +
> + ctrl_response = nvme_auth_transform_key(ctrl->dhchap_ctrl_key,
> + ctrl->dhchap_ctrl_key_len,
> + ctrl->dhchap_ctrl_key_hash,
> + ctrl->opts->subsysnqn);
> + if (IS_ERR(ctrl_response)) {
> + ret = PTR_ERR(ctrl_response);
> + return ret;
> + }
> + ret = crypto_shash_setkey(chap->shash_tfm,
> + ctrl_response, ctrl->dhchap_ctrl_key_len);
> + if (ret) {
> + dev_warn(ctrl->device, "qid %d: failed to set key, error %d\n",
> + chap->qid, ret);
> + goto out;
> + }
> +
> + dev_dbg(ctrl->device, "%s: qid %d host response seq %d transaction %d\n",
> + __func__, chap->qid, chap->s2, chap->transaction);
> + dev_dbg(ctrl->device, "%s: qid %d challenge %*ph\n",
> + __func__, chap->qid, chap->hash_len, challenge);
> + dev_dbg(ctrl->device, "%s: qid %d subsysnqn %s\n",
> + __func__, chap->qid, ctrl->opts->subsysnqn);
> + dev_dbg(ctrl->device, "%s: qid %d hostnqn %s\n",
> + __func__, chap->qid, ctrl->opts->host->nqn);
> + shash->tfm = chap->shash_tfm;
> + ret = crypto_shash_init(shash);
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, challenge, chap->hash_len);
> + if (ret)
> + goto out;
> + put_unaligned_le32(chap->s2, buf);
> + ret = crypto_shash_update(shash, buf, 4);
> + if (ret)
> + goto out;
> + put_unaligned_le16(chap->transaction, buf);
> + ret = crypto_shash_update(shash, buf, 2);
> + if (ret)
> + goto out;
> + memset(buf, 0, 4);
> + ret = crypto_shash_update(shash, buf, 1);
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, "Controller", 10);
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, ctrl->opts->subsysnqn,
> + strlen(ctrl->opts->subsysnqn));
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, buf, 1);
> + if (ret)
> + goto out;
> + ret = crypto_shash_update(shash, ctrl->opts->host->nqn,
> + strlen(ctrl->opts->host->nqn));
> + if (ret)
> + goto out;
> + ret = crypto_shash_final(shash, chap->response);
> +out:
> + if (challenge != chap->c2)
> + kfree(challenge);
> + return ret;
> +}
> +
> +int nvme_auth_generate_key(struct nvme_ctrl *ctrl)
> +{
> + u8 *secret = ctrl->opts->dhchap_secret;
> + u8 *key;
> + size_t key_len;
> + u8 key_hash;
> +
> + if (!secret)
> + return 0;
> +
> + if (sscanf(secret, "DHHC-1:%hhd:%*s:", &key_hash) != 1)
> + return -EINVAL;
> +
> + /* Pass in the secret without the 'DHHC-1:XX:' prefix */
> + key = nvme_auth_extract_secret(secret + 10, key_hash,
> + &key_len);
> + if (IS_ERR(key)) {
> + dev_dbg(ctrl->device, "failed to extract key, error %ld\n",
> + PTR_ERR(key));
> + return PTR_ERR(key);
> + }
> +
> + ctrl->dhchap_key = key;
> + key = NULL;
> + ctrl->dhchap_key_len = key_len;
> + ctrl->dhchap_key_hash = key_hash;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_generate_key);
> +
> +int nvme_auth_generate_ctrl_key(struct nvme_ctrl *ctrl)
> +{
> + u8 *secret = ctrl->opts->dhchap_ctrl_secret;
> + u8 *key;
> + size_t key_len;
> + u8 key_hash;
> +
> + if (!secret)
> + return 0;
> +
> + if (sscanf(secret, "DHHC-1:%hhd:%*s:", &key_hash) != 1)
> + return -EINVAL;
> +
> + /* Pass in the secret without the 'DHHC-1:XX:' prefix */
> + key = nvme_auth_extract_secret(secret + 10, key_hash,
> + &key_len);
> + if (IS_ERR(key))
> + return PTR_ERR(key);
> +
> + ctrl->dhchap_ctrl_key = key;
> + key = NULL;
> + ctrl->dhchap_ctrl_key_len = key_len;
> + ctrl->dhchap_ctrl_key_hash = key_hash;
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(nvme_auth_generate_ctrl_key);

This and the other look identical just operate on
a different key, perhaps merge them into one?

Overall this looks sane to me.
Just nitpicking on the logging to use err when you
hit a errors.