Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 966 insertions, 0 deletions

diff --git a/net/ceph/auth_x.c b/net/ceph/auth_x.c
new file mode 100644
index 000000000..b52732337
--- /dev/null
+++ b/net/ceph/auth_x.c
@@ -0,0 +1,966 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+
+#include <linux/ceph/decode.h>
+#include <linux/ceph/auth.h>
+#include <linux/ceph/ceph_features.h>
+#include <linux/ceph/libceph.h>
+#include <linux/ceph/messenger.h>
+
+#include "crypto.h"
+#include "auth_x.h"
+#include "auth_x_protocol.h"
+
+static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed);
+
+static int ceph_x_is_authenticated(struct ceph_auth_client *ac)
+{
+	struct ceph_x_info *xi = ac->private;
+	int need;
+
+	ceph_x_validate_tickets(ac, &need);
+	dout("ceph_x_is_authenticated want=%d need=%d have=%d\n",
+	     ac->want_keys, need, xi->have_keys);
+	return (ac->want_keys & xi->have_keys) == ac->want_keys;
+}
+
+static int ceph_x_should_authenticate(struct ceph_auth_client *ac)
+{
+	struct ceph_x_info *xi = ac->private;
+	int need;
+
+	ceph_x_validate_tickets(ac, &need);
+	dout("ceph_x_should_authenticate want=%d need=%d have=%d\n",
+	     ac->want_keys, need, xi->have_keys);
+	return need != 0;
+}
+
+static int ceph_x_encrypt_offset(void)
+{
+	return sizeof(u32) + sizeof(struct ceph_x_encrypt_header);
+}
+
+static int ceph_x_encrypt_buflen(int ilen)
+{
+	return ceph_x_encrypt_offset() + ilen + 16;
+}
+
+static int ceph_x_encrypt(struct ceph_crypto_key *secret, void *buf,
+			  int buf_len, int plaintext_len)
+{
+	struct ceph_x_encrypt_header *hdr = buf + sizeof(u32);
+	int ciphertext_len;
+	int ret;
+
+	hdr->struct_v = 1;
+	hdr->magic = cpu_to_le64(CEPHX_ENC_MAGIC);
+
+	ret = ceph_crypt(secret, true, buf + sizeof(u32), buf_len - sizeof(u32),
+			 plaintext_len + sizeof(struct ceph_x_encrypt_header),
+			 &ciphertext_len);
+	if (ret)
+		return ret;
+
+	ceph_encode_32(&buf, ciphertext_len);
+	return sizeof(u32) + ciphertext_len;
+}
+
+static int __ceph_x_decrypt(struct ceph_crypto_key *secret, void *p,
+			    int ciphertext_len)
+{
+	struct ceph_x_encrypt_header *hdr = p;
+	int plaintext_len;
+	int ret;
+
+	ret = ceph_crypt(secret, false, p, ciphertext_len, ciphertext_len,
+			 &plaintext_len);
+	if (ret)
+		return ret;
+
+	if (le64_to_cpu(hdr->magic) != CEPHX_ENC_MAGIC) {
+		pr_err("%s bad magic\n", __func__);
+		return -EINVAL;
+	}
+
+	return plaintext_len - sizeof(*hdr);
+}
+
+static int ceph_x_decrypt(struct ceph_crypto_key *secret, void **p, void *end)
+{
+	int ciphertext_len;
+	int ret;
+
+	ceph_decode_32_safe(p, end, ciphertext_len, e_inval);
+	ceph_decode_need(p, end, ciphertext_len, e_inval);
+
+	ret = __ceph_x_decrypt(secret, *p, ciphertext_len);
+	if (ret < 0)
+		return ret;
+
+	*p += ciphertext_len;
+	return ret;
+
+e_inval:
+	return -EINVAL;
+}
+
+/*
+ * get existing (or insert new) ticket handler
+ */
+static struct ceph_x_ticket_handler *
+get_ticket_handler(struct ceph_auth_client *ac, int service)
+{
+	struct ceph_x_ticket_handler *th;
+	struct ceph_x_info *xi = ac->private;
+	struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node;
+
+	while (*p) {
+		parent = *p;
+		th = rb_entry(parent, struct ceph_x_ticket_handler, node);
+		if (service < th->service)
+			p = &(*p)->rb_left;
+		else if (service > th->service)
+			p = &(*p)->rb_right;
+		else
+			return th;
+	}
+
+	/* add it */
+	th = kzalloc(sizeof(*th), GFP_NOFS);
+	if (!th)
+		return ERR_PTR(-ENOMEM);
+	th->service = service;
+	rb_link_node(&th->node, parent, p);
+	rb_insert_color(&th->node, &xi->ticket_handlers);
+	return th;
+}
+
+static void remove_ticket_handler(struct ceph_auth_client *ac,
+				  struct ceph_x_ticket_handler *th)
+{
+	struct ceph_x_info *xi = ac->private;
+
+	dout("remove_ticket_handler %p %d\n", th, th->service);
+	rb_erase(&th->node, &xi->ticket_handlers);
+	ceph_crypto_key_destroy(&th->session_key);
+	if (th->ticket_blob)
+		ceph_buffer_put(th->ticket_blob);
+	kfree(th);
+}
+
+static int process_one_ticket(struct ceph_auth_client *ac,
+			      struct ceph_crypto_key *secret,
+			      void **p, void *end)
+{
+	struct ceph_x_info *xi = ac->private;
+	int type;
+	u8 tkt_struct_v, blob_struct_v;
+	struct ceph_x_ticket_handler *th;
+	void *dp, *dend;
+	int dlen;
+	char is_enc;
+	struct timespec64 validity;
+	void *tp, *tpend;
+	void **ptp;
+	struct ceph_crypto_key new_session_key = { 0 };
+	struct ceph_buffer *new_ticket_blob;
+	time64_t new_expires, new_renew_after;
+	u64 new_secret_id;
+	int ret;
+
+	ceph_decode_need(p, end, sizeof(u32) + 1, bad);
+
+	type = ceph_decode_32(p);
+	dout(" ticket type %d %s\n", type, ceph_entity_type_name(type));
+
+	tkt_struct_v = ceph_decode_8(p);
+	if (tkt_struct_v != 1)
+		goto bad;
+
+	th = get_ticket_handler(ac, type);
+	if (IS_ERR(th)) {
+		ret = PTR_ERR(th);
+		goto out;
+	}
+
+	/* blob for me */
+	dp = *p + ceph_x_encrypt_offset();
+	ret = ceph_x_decrypt(secret, p, end);
+	if (ret < 0)
+		goto out;
+	dout(" decrypted %d bytes\n", ret);
+	dend = dp + ret;
+
+	tkt_struct_v = ceph_decode_8(&dp);
+	if (tkt_struct_v != 1)
+		goto bad;
+
+	ret = ceph_crypto_key_decode(&new_session_key, &dp, dend);
+	if (ret)
+		goto out;
+
+	ceph_decode_timespec64(&validity, dp);
+	dp += sizeof(struct ceph_timespec);
+	new_expires = ktime_get_real_seconds() + validity.tv_sec;
+	new_renew_after = new_expires - (validity.tv_sec / 4);
+	dout(" expires=%llu renew_after=%llu\n", new_expires,
+	     new_renew_after);
+
+	/* ticket blob for service */
+	ceph_decode_8_safe(p, end, is_enc, bad);
+	if (is_enc) {
+		/* encrypted */
+		tp = *p + ceph_x_encrypt_offset();
+		ret = ceph_x_decrypt(&th->session_key, p, end);
+		if (ret < 0)
+			goto out;
+		dout(" encrypted ticket, decrypted %d bytes\n", ret);
+		ptp = &tp;
+		tpend = tp + ret;
+	} else {
+		/* unencrypted */
+		ptp = p;
+		tpend = end;
+	}
+	ceph_decode_32_safe(ptp, tpend, dlen, bad);
+	dout(" ticket blob is %d bytes\n", dlen);
+	ceph_decode_need(ptp, tpend, 1 + sizeof(u64), bad);
+	blob_struct_v = ceph_decode_8(ptp);
+	if (blob_struct_v != 1)
+		goto bad;
+
+	new_secret_id = ceph_decode_64(ptp);
+	ret = ceph_decode_buffer(&new_ticket_blob, ptp, tpend);
+	if (ret)
+		goto out;
+
+	/* all is well, update our ticket */
+	ceph_crypto_key_destroy(&th->session_key);
+	if (th->ticket_blob)
+		ceph_buffer_put(th->ticket_blob);
+	th->session_key = new_session_key;
+	th->ticket_blob = new_ticket_blob;
+	th->secret_id = new_secret_id;
+	th->expires = new_expires;
+	th->renew_after = new_renew_after;
+	th->have_key = true;
+	dout(" got ticket service %d (%s) secret_id %lld len %d\n",
+	     type, ceph_entity_type_name(type), th->secret_id,
+	     (int)th->ticket_blob->vec.iov_len);
+	xi->have_keys |= th->service;
+	return 0;
+
+bad:
+	ret = -EINVAL;
+out:
+	ceph_crypto_key_destroy(&new_session_key);
+	return ret;
+}
+
+static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac,
+				    struct ceph_crypto_key *secret,
+				    void *buf, void *end)
+{
+	void *p = buf;
+	u8 reply_struct_v;
+	u32 num;
+	int ret;
+
+	ceph_decode_8_safe(&p, end, reply_struct_v, bad);
+	if (reply_struct_v != 1)
+		return -EINVAL;
+
+	ceph_decode_32_safe(&p, end, num, bad);
+	dout("%d tickets\n", num);
+
+	while (num--) {
+		ret = process_one_ticket(ac, secret, &p, end);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+
+bad:
+	return -EINVAL;
+}
+
+/*
+ * Encode and encrypt the second part (ceph_x_authorize_b) of the
+ * authorizer.  The first part (ceph_x_authorize_a) should already be
+ * encoded.
+ */
+static int encrypt_authorizer(struct ceph_x_authorizer *au,
+			      u64 *server_challenge)
+{
+	struct ceph_x_authorize_a *msg_a;
+	struct ceph_x_authorize_b *msg_b;
+	void *p, *end;
+	int ret;
+
+	msg_a = au->buf->vec.iov_base;
+	WARN_ON(msg_a->ticket_blob.secret_id != cpu_to_le64(au->secret_id));
+	p = (void *)(msg_a + 1) + le32_to_cpu(msg_a->ticket_blob.blob_len);
+	end = au->buf->vec.iov_base + au->buf->vec.iov_len;
+
+	msg_b = p + ceph_x_encrypt_offset();
+	msg_b->struct_v = 2;
+	msg_b->nonce = cpu_to_le64(au->nonce);
+	if (server_challenge) {
+		msg_b->have_challenge = 1;
+		msg_b->server_challenge_plus_one =
+		    cpu_to_le64(*server_challenge + 1);
+	} else {
+		msg_b->have_challenge = 0;
+		msg_b->server_challenge_plus_one = 0;
+	}
+
+	ret = ceph_x_encrypt(&au->session_key, p, end - p, sizeof(*msg_b));
+	if (ret < 0)
+		return ret;
+
+	p += ret;
+	if (server_challenge) {
+		WARN_ON(p != end);
+	} else {
+		WARN_ON(p > end);
+		au->buf->vec.iov_len = p - au->buf->vec.iov_base;
+	}
+
+	return 0;
+}
+
+static void ceph_x_authorizer_cleanup(struct ceph_x_authorizer *au)
+{
+	ceph_crypto_key_destroy(&au->session_key);
+	if (au->buf) {
+		ceph_buffer_put(au->buf);
+		au->buf = NULL;
+	}
+}
+
+static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
+				   struct ceph_x_ticket_handler *th,
+				   struct ceph_x_authorizer *au)
+{
+	int maxlen;
+	struct ceph_x_authorize_a *msg_a;
+	struct ceph_x_authorize_b *msg_b;
+	int ret;
+	int ticket_blob_len =
+		(th->ticket_blob ? th->ticket_blob->vec.iov_len : 0);
+
+	dout("build_authorizer for %s %p\n",
+	     ceph_entity_type_name(th->service), au);
+
+	ceph_crypto_key_destroy(&au->session_key);
+	ret = ceph_crypto_key_clone(&au->session_key, &th->session_key);
+	if (ret)
+		goto out_au;
+
+	maxlen = sizeof(*msg_a) + ticket_blob_len +
+		ceph_x_encrypt_buflen(sizeof(*msg_b));
+	dout("  need len %d\n", maxlen);
+	if (au->buf && au->buf->alloc_len < maxlen) {
+		ceph_buffer_put(au->buf);
+		au->buf = NULL;
+	}
+	if (!au->buf) {
+		au->buf = ceph_buffer_new(maxlen, GFP_NOFS);
+		if (!au->buf) {
+			ret = -ENOMEM;
+			goto out_au;
+		}
+	}
+	au->service = th->service;
+	au->secret_id = th->secret_id;
+
+	msg_a = au->buf->vec.iov_base;
+	msg_a->struct_v = 1;
+	msg_a->global_id = cpu_to_le64(ac->global_id);
+	msg_a->service_id = cpu_to_le32(th->service);
+	msg_a->ticket_blob.struct_v = 1;
+	msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id);
+	msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len);
+	if (ticket_blob_len) {
+		memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base,
+		       th->ticket_blob->vec.iov_len);
+	}
+	dout(" th %p secret_id %lld %lld\n", th, th->secret_id,
+	     le64_to_cpu(msg_a->ticket_blob.secret_id));
+
+	get_random_bytes(&au->nonce, sizeof(au->nonce));
+	ret = encrypt_authorizer(au, NULL);
+	if (ret) {
+		pr_err("failed to encrypt authorizer: %d", ret);
+		goto out_au;
+	}
+
+	dout(" built authorizer nonce %llx len %d\n", au->nonce,
+	     (int)au->buf->vec.iov_len);
+	return 0;
+
+out_au:
+	ceph_x_authorizer_cleanup(au);
+	return ret;
+}
+
+static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th,
+				void **p, void *end)
+{
+	ceph_decode_need(p, end, 1 + sizeof(u64), bad);
+	ceph_encode_8(p, 1);
+	ceph_encode_64(p, th->secret_id);
+	if (th->ticket_blob) {
+		const char *buf = th->ticket_blob->vec.iov_base;
+		u32 len = th->ticket_blob->vec.iov_len;
+
+		ceph_encode_32_safe(p, end, len, bad);
+		ceph_encode_copy_safe(p, end, buf, len, bad);
+	} else {
+		ceph_encode_32_safe(p, end, 0, bad);
+	}
+
+	return 0;
+bad:
+	return -ERANGE;
+}
+
+static bool need_key(struct ceph_x_ticket_handler *th)
+{
+	if (!th->have_key)
+		return true;
+
+	return ktime_get_real_seconds() >= th->renew_after;
+}
+
+static bool have_key(struct ceph_x_ticket_handler *th)
+{
+	if (th->have_key) {
+		if (ktime_get_real_seconds() >= th->expires)
+			th->have_key = false;
+	}
+
+	return th->have_key;
+}
+
+static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed)
+{
+	int want = ac->want_keys;
+	struct ceph_x_info *xi = ac->private;
+	int service;
+
+	*pneed = ac->want_keys & ~(xi->have_keys);
+
+	for (service = 1; service <= want; service <<= 1) {
+		struct ceph_x_ticket_handler *th;
+
+		if (!(ac->want_keys & service))
+			continue;
+
+		if (*pneed & service)
+			continue;
+
+		th = get_ticket_handler(ac, service);
+		if (IS_ERR(th)) {
+			*pneed |= service;
+			continue;
+		}
+
+		if (need_key(th))
+			*pneed |= service;
+		if (!have_key(th))
+			xi->have_keys &= ~service;
+	}
+}
+
+static int ceph_x_build_request(struct ceph_auth_client *ac,
+				void *buf, void *end)
+{
+	struct ceph_x_info *xi = ac->private;
+	int need;
+	struct ceph_x_request_header *head = buf;
+	int ret;
+	struct ceph_x_ticket_handler *th =
+		get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
+
+	if (IS_ERR(th))
+		return PTR_ERR(th);
+
+	ceph_x_validate_tickets(ac, &need);
+
+	dout("build_request want %x have %x need %x\n",
+	     ac->want_keys, xi->have_keys, need);
+
+	if (need & CEPH_ENTITY_TYPE_AUTH) {
+		struct ceph_x_authenticate *auth = (void *)(head + 1);
+		void *p = auth + 1;
+		void *enc_buf = xi->auth_authorizer.enc_buf;
+		struct ceph_x_challenge_blob *blob = enc_buf +
+							ceph_x_encrypt_offset();
+		u64 *u;
+
+		if (p > end)
+			return -ERANGE;
+
+		dout(" get_auth_session_key\n");
+		head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY);
+
+		/* encrypt and hash */
+		get_random_bytes(&auth->client_challenge, sizeof(u64));
+		blob->client_challenge = auth->client_challenge;
+		blob->server_challenge = cpu_to_le64(xi->server_challenge);
+		ret = ceph_x_encrypt(&xi->secret, enc_buf, CEPHX_AU_ENC_BUF_LEN,
+				     sizeof(*blob));
+		if (ret < 0)
+			return ret;
+
+		auth->struct_v = 1;
+		auth->key = 0;
+		for (u = (u64 *)enc_buf; u + 1 <= (u64 *)(enc_buf + ret); u++)
+			auth->key ^= *(__le64 *)u;
+		dout(" server_challenge %llx client_challenge %llx key %llx\n",
+		     xi->server_challenge, le64_to_cpu(auth->client_challenge),
+		     le64_to_cpu(auth->key));
+
+		/* now encode the old ticket if exists */
+		ret = ceph_x_encode_ticket(th, &p, end);
+		if (ret < 0)
+			return ret;
+
+		return p - buf;
+	}
+
+	if (need) {
+		void *p = head + 1;
+		struct ceph_x_service_ticket_request *req;
+
+		if (p > end)
+			return -ERANGE;
+		head->op = cpu_to_le16(CEPHX_GET_PRINCIPAL_SESSION_KEY);
+
+		ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer);
+		if (ret)
+			return ret;
+		ceph_encode_copy(&p, xi->auth_authorizer.buf->vec.iov_base,
+				 xi->auth_authorizer.buf->vec.iov_len);
+
+		req = p;
+		req->keys = cpu_to_le32(need);
+		p += sizeof(*req);
+		return p - buf;
+	}
+
+	return 0;
+}
+
+static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result,
+			       void *buf, void *end)
+{
+	struct ceph_x_info *xi = ac->private;
+	struct ceph_x_reply_header *head = buf;
+	struct ceph_x_ticket_handler *th;
+	int len = end - buf;
+	int op;
+	int ret;
+
+	if (result)
+		return result;  /* XXX hmm? */
+
+	if (xi->starting) {
+		/* it's a hello */
+		struct ceph_x_server_challenge *sc = buf;
+
+		if (len != sizeof(*sc))
+			return -EINVAL;
+		xi->server_challenge = le64_to_cpu(sc->server_challenge);
+		dout("handle_reply got server challenge %llx\n",
+		     xi->server_challenge);
+		xi->starting = false;
+		xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH;
+		return -EAGAIN;
+	}
+
+	op = le16_to_cpu(head->op);
+	result = le32_to_cpu(head->result);
+	dout("handle_reply op %d result %d\n", op, result);
+	switch (op) {
+	case CEPHX_GET_AUTH_SESSION_KEY:
+		/* verify auth key */
+		ret = ceph_x_proc_ticket_reply(ac, &xi->secret,
+					       buf + sizeof(*head), end);
+		break;
+
+	case CEPHX_GET_PRINCIPAL_SESSION_KEY:
+		th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
+		if (IS_ERR(th))
+			return PTR_ERR(th);
+		ret = ceph_x_proc_ticket_reply(ac, &th->session_key,
+					       buf + sizeof(*head), end);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+	if (ret)
+		return ret;
+	if (ac->want_keys == xi->have_keys)
+		return 0;
+	return -EAGAIN;
+}
+
+static void ceph_x_destroy_authorizer(struct ceph_authorizer *a)
+{
+	struct ceph_x_authorizer *au = (void *)a;
+
+	ceph_x_authorizer_cleanup(au);
+	kfree(au);
+}
+
+static int ceph_x_create_authorizer(
+	struct ceph_auth_client *ac, int peer_type,
+	struct ceph_auth_handshake *auth)
+{
+	struct ceph_x_authorizer *au;
+	struct ceph_x_ticket_handler *th;
+	int ret;
+
+	th = get_ticket_handler(ac, peer_type);
+	if (IS_ERR(th))
+		return PTR_ERR(th);
+
+	au = kzalloc(sizeof(*au), GFP_NOFS);
+	if (!au)
+		return -ENOMEM;
+
+	au->base.destroy = ceph_x_destroy_authorizer;
+
+	ret = ceph_x_build_authorizer(ac, th, au);
+	if (ret) {
+		kfree(au);
+		return ret;
+	}
+
+	auth->authorizer = (struct ceph_authorizer *) au;
+	auth->authorizer_buf = au->buf->vec.iov_base;
+	auth->authorizer_buf_len = au->buf->vec.iov_len;
+	auth->authorizer_reply_buf = au->enc_buf;
+	auth->authorizer_reply_buf_len = CEPHX_AU_ENC_BUF_LEN;
+	auth->sign_message = ac->ops->sign_message;
+	auth->check_message_signature = ac->ops->check_message_signature;
+
+	return 0;
+}
+
+static int ceph_x_update_authorizer(
+	struct ceph_auth_client *ac, int peer_type,
+	struct ceph_auth_handshake *auth)
+{
+	struct ceph_x_authorizer *au;
+	struct ceph_x_ticket_handler *th;
+
+	th = get_ticket_handler(ac, peer_type);
+	if (IS_ERR(th))
+		return PTR_ERR(th);
+
+	au = (struct ceph_x_authorizer *)auth->authorizer;
+	if (au->secret_id < th->secret_id) {
+		dout("ceph_x_update_authorizer service %u secret %llu < %llu\n",
+		     au->service, au->secret_id, th->secret_id);
+		return ceph_x_build_authorizer(ac, th, au);
+	}
+	return 0;
+}
+
+static int decrypt_authorize_challenge(struct ceph_x_authorizer *au,
+				       void *challenge_buf,
+				       int challenge_buf_len,
+				       u64 *server_challenge)
+{
+	struct ceph_x_authorize_challenge *ch =
+	    challenge_buf + sizeof(struct ceph_x_encrypt_header);
+	int ret;
+
+	/* no leading len */
+	ret = __ceph_x_decrypt(&au->session_key, challenge_buf,
+			       challenge_buf_len);
+	if (ret < 0)
+		return ret;
+	if (ret < sizeof(*ch)) {
+		pr_err("bad size %d for ceph_x_authorize_challenge\n", ret);
+		return -EINVAL;
+	}
+
+	*server_challenge = le64_to_cpu(ch->server_challenge);
+	return 0;
+}
+
+static int ceph_x_add_authorizer_challenge(struct ceph_auth_client *ac,
+					   struct ceph_authorizer *a,
+					   void *challenge_buf,
+					   int challenge_buf_len)
+{
+	struct ceph_x_authorizer *au = (void *)a;
+	u64 server_challenge;
+	int ret;
+
+	ret = decrypt_authorize_challenge(au, challenge_buf, challenge_buf_len,
+					  &server_challenge);
+	if (ret) {
+		pr_err("failed to decrypt authorize challenge: %d", ret);
+		return ret;
+	}
+
+	ret = encrypt_authorizer(au, &server_challenge);
+	if (ret) {
+		pr_err("failed to encrypt authorizer w/ challenge: %d", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac,
+					  struct ceph_authorizer *a)
+{
+	struct ceph_x_authorizer *au = (void *)a;
+	void *p = au->enc_buf;
+	struct ceph_x_authorize_reply *reply = p + ceph_x_encrypt_offset();
+	int ret;
+
+	ret = ceph_x_decrypt(&au->session_key, &p, p + CEPHX_AU_ENC_BUF_LEN);
+	if (ret < 0)
+		return ret;
+	if (ret < sizeof(*reply)) {
+		pr_err("bad size %d for ceph_x_authorize_reply\n", ret);
+		return -EINVAL;
+	}
+
+	if (au->nonce + 1 != le64_to_cpu(reply->nonce_plus_one))
+		ret = -EPERM;
+	else
+		ret = 0;
+	dout("verify_authorizer_reply nonce %llx got %llx ret %d\n",
+	     au->nonce, le64_to_cpu(reply->nonce_plus_one), ret);
+	return ret;
+}
+
+static void ceph_x_reset(struct ceph_auth_client *ac)
+{
+	struct ceph_x_info *xi = ac->private;
+
+	dout("reset\n");
+	xi->starting = true;
+	xi->server_challenge = 0;
+}
+
+static void ceph_x_destroy(struct ceph_auth_client *ac)
+{
+	struct ceph_x_info *xi = ac->private;
+	struct rb_node *p;
+
+	dout("ceph_x_destroy %p\n", ac);
+	ceph_crypto_key_destroy(&xi->secret);
+
+	while ((p = rb_first(&xi->ticket_handlers)) != NULL) {
+		struct ceph_x_ticket_handler *th =
+			rb_entry(p, struct ceph_x_ticket_handler, node);
+		remove_ticket_handler(ac, th);
+	}
+
+	ceph_x_authorizer_cleanup(&xi->auth_authorizer);
+
+	kfree(ac->private);
+	ac->private = NULL;
+}
+
+static void invalidate_ticket(struct ceph_auth_client *ac, int peer_type)
+{
+	struct ceph_x_ticket_handler *th;
+
+	th = get_ticket_handler(ac, peer_type);
+	if (!IS_ERR(th))
+		th->have_key = false;
+}
+
+static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac,
+					 int peer_type)
+{
+	/*
+	 * We are to invalidate a service ticket in the hopes of
+	 * getting a new, hopefully more valid, one.  But, we won't get
+	 * it unless our AUTH ticket is good, so invalidate AUTH ticket
+	 * as well, just in case.
+	 */
+	invalidate_ticket(ac, peer_type);
+	invalidate_ticket(ac, CEPH_ENTITY_TYPE_AUTH);
+}
+
+static int calc_signature(struct ceph_x_authorizer *au, struct ceph_msg *msg,
+			  __le64 *psig)
+{
+	void *enc_buf = au->enc_buf;
+	int ret;
+
+	if (!CEPH_HAVE_FEATURE(msg->con->peer_features, CEPHX_V2)) {
+		struct {
+			__le32 len;
+			__le32 header_crc;
+			__le32 front_crc;
+			__le32 middle_crc;
+			__le32 data_crc;
+		} __packed *sigblock = enc_buf + ceph_x_encrypt_offset();
+
+		sigblock->len = cpu_to_le32(4*sizeof(u32));
+		sigblock->header_crc = msg->hdr.crc;
+		sigblock->front_crc = msg->footer.front_crc;
+		sigblock->middle_crc = msg->footer.middle_crc;
+		sigblock->data_crc =  msg->footer.data_crc;
+
+		ret = ceph_x_encrypt(&au->session_key, enc_buf,
+				     CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock));
+		if (ret < 0)
+			return ret;
+
+		*psig = *(__le64 *)(enc_buf + sizeof(u32));
+	} else {
+		struct {
+			__le32 header_crc;
+			__le32 front_crc;
+			__le32 front_len;
+			__le32 middle_crc;
+			__le32 middle_len;
+			__le32 data_crc;
+			__le32 data_len;
+			__le32 seq_lower_word;
+		} __packed *sigblock = enc_buf;
+		struct {
+			__le64 a, b, c, d;
+		} __packed *penc = enc_buf;
+		int ciphertext_len;
+
+		sigblock->header_crc = msg->hdr.crc;
+		sigblock->front_crc = msg->footer.front_crc;
+		sigblock->front_len = msg->hdr.front_len;
+		sigblock->middle_crc = msg->footer.middle_crc;
+		sigblock->middle_len = msg->hdr.middle_len;
+		sigblock->data_crc =  msg->footer.data_crc;
+		sigblock->data_len = msg->hdr.data_len;
+		sigblock->seq_lower_word = *(__le32 *)&msg->hdr.seq;
+
+		/* no leading len, no ceph_x_encrypt_header */
+		ret = ceph_crypt(&au->session_key, true, enc_buf,
+				 CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock),
+				 &ciphertext_len);
+		if (ret)
+			return ret;
+
+		*psig = penc->a ^ penc->b ^ penc->c ^ penc->d;
+	}
+
+	return 0;
+}
+
+static int ceph_x_sign_message(struct ceph_auth_handshake *auth,
+			       struct ceph_msg *msg)
+{
+	__le64 sig;
+	int ret;
+
+	if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
+		return 0;
+
+	ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer,
+			     msg, &sig);
+	if (ret)
+		return ret;
+
+	msg->footer.sig = sig;
+	msg->footer.flags |= CEPH_MSG_FOOTER_SIGNED;
+	return 0;
+}
+
+static int ceph_x_check_message_signature(struct ceph_auth_handshake *auth,
+					  struct ceph_msg *msg)
+{
+	__le64 sig_check;
+	int ret;
+
+	if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
+		return 0;
+
+	ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer,
+			     msg, &sig_check);
+	if (ret)
+		return ret;
+	if (sig_check == msg->footer.sig)
+		return 0;
+	if (msg->footer.flags & CEPH_MSG_FOOTER_SIGNED)
+		dout("ceph_x_check_message_signature %p has signature %llx "
+		     "expect %llx\n", msg, msg->footer.sig, sig_check);
+	else
+		dout("ceph_x_check_message_signature %p sender did not set "
+		     "CEPH_MSG_FOOTER_SIGNED\n", msg);
+	return -EBADMSG;
+}
+
+static const struct ceph_auth_client_ops ceph_x_ops = {
+	.name = "x",
+	.is_authenticated = ceph_x_is_authenticated,
+	.should_authenticate = ceph_x_should_authenticate,
+	.build_request = ceph_x_build_request,
+	.handle_reply = ceph_x_handle_reply,
+	.create_authorizer = ceph_x_create_authorizer,
+	.update_authorizer = ceph_x_update_authorizer,
+	.add_authorizer_challenge = ceph_x_add_authorizer_challenge,
+	.verify_authorizer_reply = ceph_x_verify_authorizer_reply,
+	.invalidate_authorizer = ceph_x_invalidate_authorizer,
+	.reset =  ceph_x_reset,
+	.destroy = ceph_x_destroy,
+	.sign_message = ceph_x_sign_message,
+	.check_message_signature = ceph_x_check_message_signature,
+};
+
+
+int ceph_x_init(struct ceph_auth_client *ac)
+{
+	struct ceph_x_info *xi;
+	int ret;
+
+	dout("ceph_x_init %p\n", ac);
+	ret = -ENOMEM;
+	xi = kzalloc(sizeof(*xi), GFP_NOFS);
+	if (!xi)
+		goto out;
+
+	ret = -EINVAL;
+	if (!ac->key) {
+		pr_err("no secret set (for auth_x protocol)\n");
+		goto out_nomem;
+	}
+
+	ret = ceph_crypto_key_clone(&xi->secret, ac->key);
+	if (ret < 0) {
+		pr_err("cannot clone key: %d\n", ret);
+		goto out_nomem;
+	}
+
+	xi->starting = true;
+	xi->ticket_handlers = RB_ROOT;
+
+	ac->protocol = CEPH_AUTH_CEPHX;
+	ac->private = xi;
+	ac->ops = &ceph_x_ops;
+	return 0;
+
+out_nomem:
+	kfree(xi);
+out:
+	return ret;
+}