Merge tag 'ceph-for-5.11-rc1' of git://github.com/ceph/ceph-client
authorLinus Torvalds <torvalds@linux-foundation.org>
Thu, 17 Dec 2020 19:53:52 +0000 (11:53 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 17 Dec 2020 19:53:52 +0000 (11:53 -0800)
Pull ceph updates from Ilya Dryomov:
 "The big ticket item here is support for msgr2 on-wire protocol, which
  adds the option of full in-transit encryption using AES-GCM algorithm
  (myself).

  On top of that we have a series to avoid intermittent errors during
  recovery with recover_session=clean and some MDS request encoding work
  from Jeff, a cap handling fix and assorted observability improvements
  from Luis and Xiubo and a good number of cleanups.

  Luis also ran into a corner case with quotas which sadly means that we
  are back to denying cross-quota-realm renames"

* tag 'ceph-for-5.11-rc1' of git://github.com/ceph/ceph-client: (59 commits)
  libceph: drop ceph_auth_{create,update}_authorizer()
  libceph, ceph: make use of __ceph_auth_get_authorizer() in msgr1
  libceph, ceph: implement msgr2.1 protocol (crc and secure modes)
  libceph: introduce connection modes and ms_mode option
  libceph, rbd: ignore addr->type while comparing in some cases
  libceph, ceph: get and handle cluster maps with addrvecs
  libceph: factor out finish_auth()
  libceph: drop ac->ops->name field
  libceph: amend cephx init_protocol() and build_request()
  libceph, ceph: incorporate nautilus cephx changes
  libceph: safer en/decoding of cephx requests and replies
  libceph: more insight into ticket expiry and invalidation
  libceph: move msgr1 protocol specific fields to its own struct
  libceph: move msgr1 protocol implementation to its own file
  libceph: separate msgr1 protocol implementation
  libceph: export remaining protocol independent infrastructure
  libceph: export zero_page
  libceph: rename and export con->flags bits
  libceph: rename and export con->state states
  libceph: make con->state an int
  ...

1  2 
drivers/block/rbd.c
net/ceph/messenger_v2.c

Simple merge
index 0000000,5e38c84..c1ebb2a
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,3443 +1,3443 @@@
 -#include <crypto/sha.h>
+ // SPDX-License-Identifier: GPL-2.0
+ /*
+  * Ceph msgr2 protocol implementation
+  *
+  * Copyright (C) 2020 Ilya Dryomov <idryomov@gmail.com>
+  */
+ #include <linux/ceph/ceph_debug.h>
+ #include <crypto/aead.h>
+ #include <crypto/algapi.h>  /* for crypto_memneq() */
+ #include <crypto/hash.h>
++#include <crypto/sha2.h>
+ #include <linux/bvec.h>
+ #include <linux/crc32c.h>
+ #include <linux/net.h>
+ #include <linux/scatterlist.h>
+ #include <linux/socket.h>
+ #include <linux/sched/mm.h>
+ #include <net/sock.h>
+ #include <net/tcp.h>
+ #include <linux/ceph/ceph_features.h>
+ #include <linux/ceph/decode.h>
+ #include <linux/ceph/libceph.h>
+ #include <linux/ceph/messenger.h>
+ #include "crypto.h"  /* for CEPH_KEY_LEN and CEPH_MAX_CON_SECRET_LEN */
+ #define FRAME_TAG_HELLO                       1
+ #define FRAME_TAG_AUTH_REQUEST                2
+ #define FRAME_TAG_AUTH_BAD_METHOD     3
+ #define FRAME_TAG_AUTH_REPLY_MORE     4
+ #define FRAME_TAG_AUTH_REQUEST_MORE   5
+ #define FRAME_TAG_AUTH_DONE           6
+ #define FRAME_TAG_AUTH_SIGNATURE      7
+ #define FRAME_TAG_CLIENT_IDENT                8
+ #define FRAME_TAG_SERVER_IDENT                9
+ #define FRAME_TAG_IDENT_MISSING_FEATURES 10
+ #define FRAME_TAG_SESSION_RECONNECT   11
+ #define FRAME_TAG_SESSION_RESET               12
+ #define FRAME_TAG_SESSION_RETRY               13
+ #define FRAME_TAG_SESSION_RETRY_GLOBAL        14
+ #define FRAME_TAG_SESSION_RECONNECT_OK        15
+ #define FRAME_TAG_WAIT                        16
+ #define FRAME_TAG_MESSAGE             17
+ #define FRAME_TAG_KEEPALIVE2          18
+ #define FRAME_TAG_KEEPALIVE2_ACK      19
+ #define FRAME_TAG_ACK                 20
+ #define FRAME_LATE_STATUS_ABORTED     0x1
+ #define FRAME_LATE_STATUS_COMPLETE    0xe
+ #define FRAME_LATE_STATUS_ABORTED_MASK        0xf
+ #define IN_S_HANDLE_PREAMBLE          1
+ #define IN_S_HANDLE_CONTROL           2
+ #define IN_S_HANDLE_CONTROL_REMAINDER 3
+ #define IN_S_PREPARE_READ_DATA                4
+ #define IN_S_PREPARE_READ_DATA_CONT   5
+ #define IN_S_HANDLE_EPILOGUE          6
+ #define IN_S_FINISH_SKIP              7
+ #define OUT_S_QUEUE_DATA              1
+ #define OUT_S_QUEUE_DATA_CONT         2
+ #define OUT_S_QUEUE_ENC_PAGE          3
+ #define OUT_S_QUEUE_ZEROS             4
+ #define OUT_S_FINISH_MESSAGE          5
+ #define OUT_S_GET_NEXT                        6
+ #define CTRL_BODY(p)  ((void *)(p) + CEPH_PREAMBLE_LEN)
+ #define FRONT_PAD(p)  ((void *)(p) + CEPH_EPILOGUE_SECURE_LEN)
+ #define MIDDLE_PAD(p) (FRONT_PAD(p) + CEPH_GCM_BLOCK_LEN)
+ #define DATA_PAD(p)   (MIDDLE_PAD(p) + CEPH_GCM_BLOCK_LEN)
+ #define CEPH_MSG_FLAGS (MSG_DONTWAIT | MSG_NOSIGNAL)
+ static int do_recvmsg(struct socket *sock, struct iov_iter *it)
+ {
+       struct msghdr msg = { .msg_flags = CEPH_MSG_FLAGS };
+       int ret;
+       msg.msg_iter = *it;
+       while (iov_iter_count(it)) {
+               ret = sock_recvmsg(sock, &msg, msg.msg_flags);
+               if (ret <= 0) {
+                       if (ret == -EAGAIN)
+                               ret = 0;
+                       return ret;
+               }
+               iov_iter_advance(it, ret);
+       }
+       WARN_ON(msg_data_left(&msg));
+       return 1;
+ }
+ /*
+  * Read as much as possible.
+  *
+  * Return:
+  *   1 - done, nothing (else) to read
+  *   0 - socket is empty, need to wait
+  *  <0 - error
+  */
+ static int ceph_tcp_recv(struct ceph_connection *con)
+ {
+       int ret;
+       dout("%s con %p %s %zu\n", __func__, con,
+            iov_iter_is_discard(&con->v2.in_iter) ? "discard" : "need",
+            iov_iter_count(&con->v2.in_iter));
+       ret = do_recvmsg(con->sock, &con->v2.in_iter);
+       dout("%s con %p ret %d left %zu\n", __func__, con, ret,
+            iov_iter_count(&con->v2.in_iter));
+       return ret;
+ }
+ static int do_sendmsg(struct socket *sock, struct iov_iter *it)
+ {
+       struct msghdr msg = { .msg_flags = CEPH_MSG_FLAGS };
+       int ret;
+       msg.msg_iter = *it;
+       while (iov_iter_count(it)) {
+               ret = sock_sendmsg(sock, &msg);
+               if (ret <= 0) {
+                       if (ret == -EAGAIN)
+                               ret = 0;
+                       return ret;
+               }
+               iov_iter_advance(it, ret);
+       }
+       WARN_ON(msg_data_left(&msg));
+       return 1;
+ }
+ static int do_try_sendpage(struct socket *sock, struct iov_iter *it)
+ {
+       struct msghdr msg = { .msg_flags = CEPH_MSG_FLAGS };
+       struct bio_vec bv;
+       int ret;
+       if (WARN_ON(!iov_iter_is_bvec(it)))
+               return -EINVAL;
+       while (iov_iter_count(it)) {
+               /* iov_iter_iovec() for ITER_BVEC */
+               bv.bv_page = it->bvec->bv_page;
+               bv.bv_offset = it->bvec->bv_offset + it->iov_offset;
+               bv.bv_len = min(iov_iter_count(it),
+                               it->bvec->bv_len - it->iov_offset);
+               /*
+                * sendpage cannot properly handle pages with
+                * page_count == 0, we need to fall back to sendmsg if
+                * that's the case.
+                *
+                * Same goes for slab pages: skb_can_coalesce() allows
+                * coalescing neighboring slab objects into a single frag
+                * which triggers one of hardened usercopy checks.
+                */
+               if (sendpage_ok(bv.bv_page)) {
+                       ret = sock->ops->sendpage(sock, bv.bv_page,
+                                                 bv.bv_offset, bv.bv_len,
+                                                 CEPH_MSG_FLAGS);
+               } else {
+                       iov_iter_bvec(&msg.msg_iter, WRITE, &bv, 1, bv.bv_len);
+                       ret = sock_sendmsg(sock, &msg);
+               }
+               if (ret <= 0) {
+                       if (ret == -EAGAIN)
+                               ret = 0;
+                       return ret;
+               }
+               iov_iter_advance(it, ret);
+       }
+       return 1;
+ }
+ /*
+  * Write as much as possible.  The socket is expected to be corked,
+  * so we don't bother with MSG_MORE/MSG_SENDPAGE_NOTLAST here.
+  *
+  * Return:
+  *   1 - done, nothing (else) to write
+  *   0 - socket is full, need to wait
+  *  <0 - error
+  */
+ static int ceph_tcp_send(struct ceph_connection *con)
+ {
+       int ret;
+       dout("%s con %p have %zu try_sendpage %d\n", __func__, con,
+            iov_iter_count(&con->v2.out_iter), con->v2.out_iter_sendpage);
+       if (con->v2.out_iter_sendpage)
+               ret = do_try_sendpage(con->sock, &con->v2.out_iter);
+       else
+               ret = do_sendmsg(con->sock, &con->v2.out_iter);
+       dout("%s con %p ret %d left %zu\n", __func__, con, ret,
+            iov_iter_count(&con->v2.out_iter));
+       return ret;
+ }
+ static void add_in_kvec(struct ceph_connection *con, void *buf, int len)
+ {
+       BUG_ON(con->v2.in_kvec_cnt >= ARRAY_SIZE(con->v2.in_kvecs));
+       WARN_ON(!iov_iter_is_kvec(&con->v2.in_iter));
+       con->v2.in_kvecs[con->v2.in_kvec_cnt].iov_base = buf;
+       con->v2.in_kvecs[con->v2.in_kvec_cnt].iov_len = len;
+       con->v2.in_kvec_cnt++;
+       con->v2.in_iter.nr_segs++;
+       con->v2.in_iter.count += len;
+ }
+ static void reset_in_kvecs(struct ceph_connection *con)
+ {
+       WARN_ON(iov_iter_count(&con->v2.in_iter));
+       con->v2.in_kvec_cnt = 0;
+       iov_iter_kvec(&con->v2.in_iter, READ, con->v2.in_kvecs, 0, 0);
+ }
+ static void set_in_bvec(struct ceph_connection *con, const struct bio_vec *bv)
+ {
+       WARN_ON(iov_iter_count(&con->v2.in_iter));
+       con->v2.in_bvec = *bv;
+       iov_iter_bvec(&con->v2.in_iter, READ, &con->v2.in_bvec, 1, bv->bv_len);
+ }
+ static void set_in_skip(struct ceph_connection *con, int len)
+ {
+       WARN_ON(iov_iter_count(&con->v2.in_iter));
+       dout("%s con %p len %d\n", __func__, con, len);
+       iov_iter_discard(&con->v2.in_iter, READ, len);
+ }
+ static void add_out_kvec(struct ceph_connection *con, void *buf, int len)
+ {
+       BUG_ON(con->v2.out_kvec_cnt >= ARRAY_SIZE(con->v2.out_kvecs));
+       WARN_ON(!iov_iter_is_kvec(&con->v2.out_iter));
+       WARN_ON(con->v2.out_zero);
+       con->v2.out_kvecs[con->v2.out_kvec_cnt].iov_base = buf;
+       con->v2.out_kvecs[con->v2.out_kvec_cnt].iov_len = len;
+       con->v2.out_kvec_cnt++;
+       con->v2.out_iter.nr_segs++;
+       con->v2.out_iter.count += len;
+ }
+ static void reset_out_kvecs(struct ceph_connection *con)
+ {
+       WARN_ON(iov_iter_count(&con->v2.out_iter));
+       WARN_ON(con->v2.out_zero);
+       con->v2.out_kvec_cnt = 0;
+       iov_iter_kvec(&con->v2.out_iter, WRITE, con->v2.out_kvecs, 0, 0);
+       con->v2.out_iter_sendpage = false;
+ }
+ static void set_out_bvec(struct ceph_connection *con, const struct bio_vec *bv,
+                        bool zerocopy)
+ {
+       WARN_ON(iov_iter_count(&con->v2.out_iter));
+       WARN_ON(con->v2.out_zero);
+       con->v2.out_bvec = *bv;
+       con->v2.out_iter_sendpage = zerocopy;
+       iov_iter_bvec(&con->v2.out_iter, WRITE, &con->v2.out_bvec, 1,
+                     con->v2.out_bvec.bv_len);
+ }
+ static void set_out_bvec_zero(struct ceph_connection *con)
+ {
+       WARN_ON(iov_iter_count(&con->v2.out_iter));
+       WARN_ON(!con->v2.out_zero);
+       con->v2.out_bvec.bv_page = ceph_zero_page;
+       con->v2.out_bvec.bv_offset = 0;
+       con->v2.out_bvec.bv_len = min(con->v2.out_zero, (int)PAGE_SIZE);
+       con->v2.out_iter_sendpage = true;
+       iov_iter_bvec(&con->v2.out_iter, WRITE, &con->v2.out_bvec, 1,
+                     con->v2.out_bvec.bv_len);
+ }
+ static void out_zero_add(struct ceph_connection *con, int len)
+ {
+       dout("%s con %p len %d\n", __func__, con, len);
+       con->v2.out_zero += len;
+ }
+ static void *alloc_conn_buf(struct ceph_connection *con, int len)
+ {
+       void *buf;
+       dout("%s con %p len %d\n", __func__, con, len);
+       if (WARN_ON(con->v2.conn_buf_cnt >= ARRAY_SIZE(con->v2.conn_bufs)))
+               return NULL;
+       buf = ceph_kvmalloc(len, GFP_NOIO);
+       if (!buf)
+               return NULL;
+       con->v2.conn_bufs[con->v2.conn_buf_cnt++] = buf;
+       return buf;
+ }
+ static void free_conn_bufs(struct ceph_connection *con)
+ {
+       while (con->v2.conn_buf_cnt)
+               kvfree(con->v2.conn_bufs[--con->v2.conn_buf_cnt]);
+ }
+ static void add_in_sign_kvec(struct ceph_connection *con, void *buf, int len)
+ {
+       BUG_ON(con->v2.in_sign_kvec_cnt >= ARRAY_SIZE(con->v2.in_sign_kvecs));
+       con->v2.in_sign_kvecs[con->v2.in_sign_kvec_cnt].iov_base = buf;
+       con->v2.in_sign_kvecs[con->v2.in_sign_kvec_cnt].iov_len = len;
+       con->v2.in_sign_kvec_cnt++;
+ }
+ static void clear_in_sign_kvecs(struct ceph_connection *con)
+ {
+       con->v2.in_sign_kvec_cnt = 0;
+ }
+ static void add_out_sign_kvec(struct ceph_connection *con, void *buf, int len)
+ {
+       BUG_ON(con->v2.out_sign_kvec_cnt >= ARRAY_SIZE(con->v2.out_sign_kvecs));
+       con->v2.out_sign_kvecs[con->v2.out_sign_kvec_cnt].iov_base = buf;
+       con->v2.out_sign_kvecs[con->v2.out_sign_kvec_cnt].iov_len = len;
+       con->v2.out_sign_kvec_cnt++;
+ }
+ static void clear_out_sign_kvecs(struct ceph_connection *con)
+ {
+       con->v2.out_sign_kvec_cnt = 0;
+ }
+ static bool con_secure(struct ceph_connection *con)
+ {
+       return con->v2.con_mode == CEPH_CON_MODE_SECURE;
+ }
+ static int front_len(const struct ceph_msg *msg)
+ {
+       return le32_to_cpu(msg->hdr.front_len);
+ }
+ static int middle_len(const struct ceph_msg *msg)
+ {
+       return le32_to_cpu(msg->hdr.middle_len);
+ }
+ static int data_len(const struct ceph_msg *msg)
+ {
+       return le32_to_cpu(msg->hdr.data_len);
+ }
+ static bool need_padding(int len)
+ {
+       return !IS_ALIGNED(len, CEPH_GCM_BLOCK_LEN);
+ }
+ static int padded_len(int len)
+ {
+       return ALIGN(len, CEPH_GCM_BLOCK_LEN);
+ }
+ static int padding_len(int len)
+ {
+       return padded_len(len) - len;
+ }
+ /* preamble + control segment */
+ static int head_onwire_len(int ctrl_len, bool secure)
+ {
+       int head_len;
+       int rem_len;
+       if (secure) {
+               head_len = CEPH_PREAMBLE_SECURE_LEN;
+               if (ctrl_len > CEPH_PREAMBLE_INLINE_LEN) {
+                       rem_len = ctrl_len - CEPH_PREAMBLE_INLINE_LEN;
+                       head_len += padded_len(rem_len) + CEPH_GCM_TAG_LEN;
+               }
+       } else {
+               head_len = CEPH_PREAMBLE_PLAIN_LEN;
+               if (ctrl_len)
+                       head_len += ctrl_len + CEPH_CRC_LEN;
+       }
+       return head_len;
+ }
+ /* front, middle and data segments + epilogue */
+ static int __tail_onwire_len(int front_len, int middle_len, int data_len,
+                            bool secure)
+ {
+       if (!front_len && !middle_len && !data_len)
+               return 0;
+       if (!secure)
+               return front_len + middle_len + data_len +
+                      CEPH_EPILOGUE_PLAIN_LEN;
+       return padded_len(front_len) + padded_len(middle_len) +
+              padded_len(data_len) + CEPH_EPILOGUE_SECURE_LEN;
+ }
+ static int tail_onwire_len(const struct ceph_msg *msg, bool secure)
+ {
+       return __tail_onwire_len(front_len(msg), middle_len(msg),
+                                data_len(msg), secure);
+ }
+ /* head_onwire_len(sizeof(struct ceph_msg_header2), false) */
+ #define MESSAGE_HEAD_PLAIN_LEN        (CEPH_PREAMBLE_PLAIN_LEN +              \
+                                sizeof(struct ceph_msg_header2) +      \
+                                CEPH_CRC_LEN)
+ static const int frame_aligns[] = {
+       sizeof(void *),
+       sizeof(void *),
+       sizeof(void *),
+       PAGE_SIZE
+ };
+ /*
+  * Discards trailing empty segments, unless there is just one segment.
+  * A frame always has at least one (possibly empty) segment.
+  */
+ static int calc_segment_count(const int *lens, int len_cnt)
+ {
+       int i;
+       for (i = len_cnt - 1; i >= 0; i--) {
+               if (lens[i])
+                       return i + 1;
+       }
+       return 1;
+ }
+ static void init_frame_desc(struct ceph_frame_desc *desc, int tag,
+                           const int *lens, int len_cnt)
+ {
+       int i;
+       memset(desc, 0, sizeof(*desc));
+       desc->fd_tag = tag;
+       desc->fd_seg_cnt = calc_segment_count(lens, len_cnt);
+       BUG_ON(desc->fd_seg_cnt > CEPH_FRAME_MAX_SEGMENT_COUNT);
+       for (i = 0; i < desc->fd_seg_cnt; i++) {
+               desc->fd_lens[i] = lens[i];
+               desc->fd_aligns[i] = frame_aligns[i];
+       }
+ }
+ /*
+  * Preamble crc covers everything up to itself (28 bytes) and
+  * is calculated and verified irrespective of the connection mode
+  * (i.e. even if the frame is encrypted).
+  */
+ static void encode_preamble(const struct ceph_frame_desc *desc, void *p)
+ {
+       void *crcp = p + CEPH_PREAMBLE_LEN - CEPH_CRC_LEN;
+       void *start = p;
+       int i;
+       memset(p, 0, CEPH_PREAMBLE_LEN);
+       ceph_encode_8(&p, desc->fd_tag);
+       ceph_encode_8(&p, desc->fd_seg_cnt);
+       for (i = 0; i < desc->fd_seg_cnt; i++) {
+               ceph_encode_32(&p, desc->fd_lens[i]);
+               ceph_encode_16(&p, desc->fd_aligns[i]);
+       }
+       put_unaligned_le32(crc32c(0, start, crcp - start), crcp);
+ }
+ static int decode_preamble(void *p, struct ceph_frame_desc *desc)
+ {
+       void *crcp = p + CEPH_PREAMBLE_LEN - CEPH_CRC_LEN;
+       u32 crc, expected_crc;
+       int i;
+       crc = crc32c(0, p, crcp - p);
+       expected_crc = get_unaligned_le32(crcp);
+       if (crc != expected_crc) {
+               pr_err("bad preamble crc, calculated %u, expected %u\n",
+                      crc, expected_crc);
+               return -EBADMSG;
+       }
+       memset(desc, 0, sizeof(*desc));
+       desc->fd_tag = ceph_decode_8(&p);
+       desc->fd_seg_cnt = ceph_decode_8(&p);
+       if (desc->fd_seg_cnt < 1 ||
+           desc->fd_seg_cnt > CEPH_FRAME_MAX_SEGMENT_COUNT) {
+               pr_err("bad segment count %d\n", desc->fd_seg_cnt);
+               return -EINVAL;
+       }
+       for (i = 0; i < desc->fd_seg_cnt; i++) {
+               desc->fd_lens[i] = ceph_decode_32(&p);
+               desc->fd_aligns[i] = ceph_decode_16(&p);
+       }
+       /*
+        * This would fire for FRAME_TAG_WAIT (it has one empty
+        * segment), but we should never get it as client.
+        */
+       if (!desc->fd_lens[desc->fd_seg_cnt - 1]) {
+               pr_err("last segment empty\n");
+               return -EINVAL;
+       }
+       if (desc->fd_lens[0] > CEPH_MSG_MAX_CONTROL_LEN) {
+               pr_err("control segment too big %d\n", desc->fd_lens[0]);
+               return -EINVAL;
+       }
+       if (desc->fd_lens[1] > CEPH_MSG_MAX_FRONT_LEN) {
+               pr_err("front segment too big %d\n", desc->fd_lens[1]);
+               return -EINVAL;
+       }
+       if (desc->fd_lens[2] > CEPH_MSG_MAX_MIDDLE_LEN) {
+               pr_err("middle segment too big %d\n", desc->fd_lens[2]);
+               return -EINVAL;
+       }
+       if (desc->fd_lens[3] > CEPH_MSG_MAX_DATA_LEN) {
+               pr_err("data segment too big %d\n", desc->fd_lens[3]);
+               return -EINVAL;
+       }
+       return 0;
+ }
+ static void encode_epilogue_plain(struct ceph_connection *con, bool aborted)
+ {
+       con->v2.out_epil.late_status = aborted ? FRAME_LATE_STATUS_ABORTED :
+                                                FRAME_LATE_STATUS_COMPLETE;
+       cpu_to_le32s(&con->v2.out_epil.front_crc);
+       cpu_to_le32s(&con->v2.out_epil.middle_crc);
+       cpu_to_le32s(&con->v2.out_epil.data_crc);
+ }
+ static void encode_epilogue_secure(struct ceph_connection *con, bool aborted)
+ {
+       memset(&con->v2.out_epil, 0, sizeof(con->v2.out_epil));
+       con->v2.out_epil.late_status = aborted ? FRAME_LATE_STATUS_ABORTED :
+                                                FRAME_LATE_STATUS_COMPLETE;
+ }
+ static int decode_epilogue(void *p, u32 *front_crc, u32 *middle_crc,
+                          u32 *data_crc)
+ {
+       u8 late_status;
+       late_status = ceph_decode_8(&p);
+       if ((late_status & FRAME_LATE_STATUS_ABORTED_MASK) !=
+                       FRAME_LATE_STATUS_COMPLETE) {
+               /* we should never get an aborted message as client */
+               pr_err("bad late_status 0x%x\n", late_status);
+               return -EINVAL;
+       }
+       if (front_crc && middle_crc && data_crc) {
+               *front_crc = ceph_decode_32(&p);
+               *middle_crc = ceph_decode_32(&p);
+               *data_crc = ceph_decode_32(&p);
+       }
+       return 0;
+ }
+ static void fill_header(struct ceph_msg_header *hdr,
+                       const struct ceph_msg_header2 *hdr2,
+                       int front_len, int middle_len, int data_len,
+                       const struct ceph_entity_name *peer_name)
+ {
+       hdr->seq = hdr2->seq;
+       hdr->tid = hdr2->tid;
+       hdr->type = hdr2->type;
+       hdr->priority = hdr2->priority;
+       hdr->version = hdr2->version;
+       hdr->front_len = cpu_to_le32(front_len);
+       hdr->middle_len = cpu_to_le32(middle_len);
+       hdr->data_len = cpu_to_le32(data_len);
+       hdr->data_off = hdr2->data_off;
+       hdr->src = *peer_name;
+       hdr->compat_version = hdr2->compat_version;
+       hdr->reserved = 0;
+       hdr->crc = 0;
+ }
+ static void fill_header2(struct ceph_msg_header2 *hdr2,
+                        const struct ceph_msg_header *hdr, u64 ack_seq)
+ {
+       hdr2->seq = hdr->seq;
+       hdr2->tid = hdr->tid;
+       hdr2->type = hdr->type;
+       hdr2->priority = hdr->priority;
+       hdr2->version = hdr->version;
+       hdr2->data_pre_padding_len = 0;
+       hdr2->data_off = hdr->data_off;
+       hdr2->ack_seq = cpu_to_le64(ack_seq);
+       hdr2->flags = 0;
+       hdr2->compat_version = hdr->compat_version;
+       hdr2->reserved = 0;
+ }
+ static int verify_control_crc(struct ceph_connection *con)
+ {
+       int ctrl_len = con->v2.in_desc.fd_lens[0];
+       u32 crc, expected_crc;
+       WARN_ON(con->v2.in_kvecs[0].iov_len != ctrl_len);
+       WARN_ON(con->v2.in_kvecs[1].iov_len != CEPH_CRC_LEN);
+       crc = crc32c(-1, con->v2.in_kvecs[0].iov_base, ctrl_len);
+       expected_crc = get_unaligned_le32(con->v2.in_kvecs[1].iov_base);
+       if (crc != expected_crc) {
+               pr_err("bad control crc, calculated %u, expected %u\n",
+                      crc, expected_crc);
+               return -EBADMSG;
+       }
+       return 0;
+ }
+ static int verify_epilogue_crcs(struct ceph_connection *con, u32 front_crc,
+                               u32 middle_crc, u32 data_crc)
+ {
+       if (front_len(con->in_msg)) {
+               con->in_front_crc = crc32c(-1, con->in_msg->front.iov_base,
+                                          front_len(con->in_msg));
+       } else {
+               WARN_ON(!middle_len(con->in_msg) && !data_len(con->in_msg));
+               con->in_front_crc = -1;
+       }
+       if (middle_len(con->in_msg))
+               con->in_middle_crc = crc32c(-1,
+                                           con->in_msg->middle->vec.iov_base,
+                                           middle_len(con->in_msg));
+       else if (data_len(con->in_msg))
+               con->in_middle_crc = -1;
+       else
+               con->in_middle_crc = 0;
+       if (!data_len(con->in_msg))
+               con->in_data_crc = 0;
+       dout("%s con %p msg %p crcs %u %u %u\n", __func__, con, con->in_msg,
+            con->in_front_crc, con->in_middle_crc, con->in_data_crc);
+       if (con->in_front_crc != front_crc) {
+               pr_err("bad front crc, calculated %u, expected %u\n",
+                      con->in_front_crc, front_crc);
+               return -EBADMSG;
+       }
+       if (con->in_middle_crc != middle_crc) {
+               pr_err("bad middle crc, calculated %u, expected %u\n",
+                      con->in_middle_crc, middle_crc);
+               return -EBADMSG;
+       }
+       if (con->in_data_crc != data_crc) {
+               pr_err("bad data crc, calculated %u, expected %u\n",
+                      con->in_data_crc, data_crc);
+               return -EBADMSG;
+       }
+       return 0;
+ }
+ static int setup_crypto(struct ceph_connection *con,
+                       u8 *session_key, int session_key_len,
+                       u8 *con_secret, int con_secret_len)
+ {
+       unsigned int noio_flag;
+       void *p;
+       int ret;
+       dout("%s con %p con_mode %d session_key_len %d con_secret_len %d\n",
+            __func__, con, con->v2.con_mode, session_key_len, con_secret_len);
+       WARN_ON(con->v2.hmac_tfm || con->v2.gcm_tfm || con->v2.gcm_req);
+       if (con->v2.con_mode != CEPH_CON_MODE_CRC &&
+           con->v2.con_mode != CEPH_CON_MODE_SECURE) {
+               pr_err("bad con_mode %d\n", con->v2.con_mode);
+               return -EINVAL;
+       }
+       if (!session_key_len) {
+               WARN_ON(con->v2.con_mode != CEPH_CON_MODE_CRC);
+               WARN_ON(con_secret_len);
+               return 0;  /* auth_none */
+       }
+       noio_flag = memalloc_noio_save();
+       con->v2.hmac_tfm = crypto_alloc_shash("hmac(sha256)", 0, 0);
+       memalloc_noio_restore(noio_flag);
+       if (IS_ERR(con->v2.hmac_tfm)) {
+               ret = PTR_ERR(con->v2.hmac_tfm);
+               con->v2.hmac_tfm = NULL;
+               pr_err("failed to allocate hmac tfm context: %d\n", ret);
+               return ret;
+       }
+       WARN_ON((unsigned long)session_key &
+               crypto_shash_alignmask(con->v2.hmac_tfm));
+       ret = crypto_shash_setkey(con->v2.hmac_tfm, session_key,
+                                 session_key_len);
+       if (ret) {
+               pr_err("failed to set hmac key: %d\n", ret);
+               return ret;
+       }
+       if (con->v2.con_mode == CEPH_CON_MODE_CRC) {
+               WARN_ON(con_secret_len);
+               return 0;  /* auth_x, plain mode */
+       }
+       if (con_secret_len < CEPH_GCM_KEY_LEN + 2 * CEPH_GCM_IV_LEN) {
+               pr_err("con_secret too small %d\n", con_secret_len);
+               return -EINVAL;
+       }
+       noio_flag = memalloc_noio_save();
+       con->v2.gcm_tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
+       memalloc_noio_restore(noio_flag);
+       if (IS_ERR(con->v2.gcm_tfm)) {
+               ret = PTR_ERR(con->v2.gcm_tfm);
+               con->v2.gcm_tfm = NULL;
+               pr_err("failed to allocate gcm tfm context: %d\n", ret);
+               return ret;
+       }
+       p = con_secret;
+       WARN_ON((unsigned long)p & crypto_aead_alignmask(con->v2.gcm_tfm));
+       ret = crypto_aead_setkey(con->v2.gcm_tfm, p, CEPH_GCM_KEY_LEN);
+       if (ret) {
+               pr_err("failed to set gcm key: %d\n", ret);
+               return ret;
+       }
+       p += CEPH_GCM_KEY_LEN;
+       WARN_ON(crypto_aead_ivsize(con->v2.gcm_tfm) != CEPH_GCM_IV_LEN);
+       ret = crypto_aead_setauthsize(con->v2.gcm_tfm, CEPH_GCM_TAG_LEN);
+       if (ret) {
+               pr_err("failed to set gcm tag size: %d\n", ret);
+               return ret;
+       }
+       con->v2.gcm_req = aead_request_alloc(con->v2.gcm_tfm, GFP_NOIO);
+       if (!con->v2.gcm_req) {
+               pr_err("failed to allocate gcm request\n");
+               return -ENOMEM;
+       }
+       crypto_init_wait(&con->v2.gcm_wait);
+       aead_request_set_callback(con->v2.gcm_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+                                 crypto_req_done, &con->v2.gcm_wait);
+       memcpy(&con->v2.in_gcm_nonce, p, CEPH_GCM_IV_LEN);
+       memcpy(&con->v2.out_gcm_nonce, p + CEPH_GCM_IV_LEN, CEPH_GCM_IV_LEN);
+       return 0;  /* auth_x, secure mode */
+ }
+ static int hmac_sha256(struct ceph_connection *con, const struct kvec *kvecs,
+                      int kvec_cnt, u8 *hmac)
+ {
+       SHASH_DESC_ON_STACK(desc, con->v2.hmac_tfm);  /* tfm arg is ignored */
+       int ret;
+       int i;
+       dout("%s con %p hmac_tfm %p kvec_cnt %d\n", __func__, con,
+            con->v2.hmac_tfm, kvec_cnt);
+       if (!con->v2.hmac_tfm) {
+               memset(hmac, 0, SHA256_DIGEST_SIZE);
+               return 0;  /* auth_none */
+       }
+       desc->tfm = con->v2.hmac_tfm;
+       ret = crypto_shash_init(desc);
+       if (ret)
+               return ret;
+       for (i = 0; i < kvec_cnt; i++) {
+               WARN_ON((unsigned long)kvecs[i].iov_base &
+                       crypto_shash_alignmask(con->v2.hmac_tfm));
+               ret = crypto_shash_update(desc, kvecs[i].iov_base,
+                                         kvecs[i].iov_len);
+               if (ret)
+                       return ret;
+       }
+       ret = crypto_shash_final(desc, hmac);
+       if (ret)
+               return ret;
+       shash_desc_zero(desc);
+       return 0;  /* auth_x, both plain and secure modes */
+ }
+ static void gcm_inc_nonce(struct ceph_gcm_nonce *nonce)
+ {
+       u64 counter;
+       counter = le64_to_cpu(nonce->counter);
+       nonce->counter = cpu_to_le64(counter + 1);
+ }
+ static int gcm_crypt(struct ceph_connection *con, bool encrypt,
+                    struct scatterlist *src, struct scatterlist *dst,
+                    int src_len)
+ {
+       struct ceph_gcm_nonce *nonce;
+       int ret;
+       nonce = encrypt ? &con->v2.out_gcm_nonce : &con->v2.in_gcm_nonce;
+       aead_request_set_ad(con->v2.gcm_req, 0);  /* no AAD */
+       aead_request_set_crypt(con->v2.gcm_req, src, dst, src_len, (u8 *)nonce);
+       ret = crypto_wait_req(encrypt ? crypto_aead_encrypt(con->v2.gcm_req) :
+                                       crypto_aead_decrypt(con->v2.gcm_req),
+                             &con->v2.gcm_wait);
+       if (ret)
+               return ret;
+       gcm_inc_nonce(nonce);
+       return 0;
+ }
+ static void get_bvec_at(struct ceph_msg_data_cursor *cursor,
+                       struct bio_vec *bv)
+ {
+       struct page *page;
+       size_t off, len;
+       WARN_ON(!cursor->total_resid);
+       /* skip zero-length data items */
+       while (!cursor->resid)
+               ceph_msg_data_advance(cursor, 0);
+       /* get a piece of data, cursor isn't advanced */
+       page = ceph_msg_data_next(cursor, &off, &len, NULL);
+       bv->bv_page = page;
+       bv->bv_offset = off;
+       bv->bv_len = len;
+ }
+ static int calc_sg_cnt(void *buf, int buf_len)
+ {
+       int sg_cnt;
+       if (!buf_len)
+               return 0;
+       sg_cnt = need_padding(buf_len) ? 1 : 0;
+       if (is_vmalloc_addr(buf)) {
+               WARN_ON(offset_in_page(buf));
+               sg_cnt += PAGE_ALIGN(buf_len) >> PAGE_SHIFT;
+       } else {
+               sg_cnt++;
+       }
+       return sg_cnt;
+ }
+ static int calc_sg_cnt_cursor(struct ceph_msg_data_cursor *cursor)
+ {
+       int data_len = cursor->total_resid;
+       struct bio_vec bv;
+       int sg_cnt;
+       if (!data_len)
+               return 0;
+       sg_cnt = need_padding(data_len) ? 1 : 0;
+       do {
+               get_bvec_at(cursor, &bv);
+               sg_cnt++;
+               ceph_msg_data_advance(cursor, bv.bv_len);
+       } while (cursor->total_resid);
+       return sg_cnt;
+ }
+ static void init_sgs(struct scatterlist **sg, void *buf, int buf_len, u8 *pad)
+ {
+       void *end = buf + buf_len;
+       struct page *page;
+       int len;
+       void *p;
+       if (!buf_len)
+               return;
+       if (is_vmalloc_addr(buf)) {
+               p = buf;
+               do {
+                       page = vmalloc_to_page(p);
+                       len = min_t(int, end - p, PAGE_SIZE);
+                       WARN_ON(!page || !len || offset_in_page(p));
+                       sg_set_page(*sg, page, len, 0);
+                       *sg = sg_next(*sg);
+                       p += len;
+               } while (p != end);
+       } else {
+               sg_set_buf(*sg, buf, buf_len);
+               *sg = sg_next(*sg);
+       }
+       if (need_padding(buf_len)) {
+               sg_set_buf(*sg, pad, padding_len(buf_len));
+               *sg = sg_next(*sg);
+       }
+ }
+ static void init_sgs_cursor(struct scatterlist **sg,
+                           struct ceph_msg_data_cursor *cursor, u8 *pad)
+ {
+       int data_len = cursor->total_resid;
+       struct bio_vec bv;
+       if (!data_len)
+               return;
+       do {
+               get_bvec_at(cursor, &bv);
+               sg_set_page(*sg, bv.bv_page, bv.bv_len, bv.bv_offset);
+               *sg = sg_next(*sg);
+               ceph_msg_data_advance(cursor, bv.bv_len);
+       } while (cursor->total_resid);
+       if (need_padding(data_len)) {
+               sg_set_buf(*sg, pad, padding_len(data_len));
+               *sg = sg_next(*sg);
+       }
+ }
+ static int setup_message_sgs(struct sg_table *sgt, struct ceph_msg *msg,
+                            u8 *front_pad, u8 *middle_pad, u8 *data_pad,
+                            void *epilogue, bool add_tag)
+ {
+       struct ceph_msg_data_cursor cursor;
+       struct scatterlist *cur_sg;
+       int sg_cnt;
+       int ret;
+       if (!front_len(msg) && !middle_len(msg) && !data_len(msg))
+               return 0;
+       sg_cnt = 1;  /* epilogue + [auth tag] */
+       if (front_len(msg))
+               sg_cnt += calc_sg_cnt(msg->front.iov_base,
+                                     front_len(msg));
+       if (middle_len(msg))
+               sg_cnt += calc_sg_cnt(msg->middle->vec.iov_base,
+                                     middle_len(msg));
+       if (data_len(msg)) {
+               ceph_msg_data_cursor_init(&cursor, msg, data_len(msg));
+               sg_cnt += calc_sg_cnt_cursor(&cursor);
+       }
+       ret = sg_alloc_table(sgt, sg_cnt, GFP_NOIO);
+       if (ret)
+               return ret;
+       cur_sg = sgt->sgl;
+       if (front_len(msg))
+               init_sgs(&cur_sg, msg->front.iov_base, front_len(msg),
+                        front_pad);
+       if (middle_len(msg))
+               init_sgs(&cur_sg, msg->middle->vec.iov_base, middle_len(msg),
+                        middle_pad);
+       if (data_len(msg)) {
+               ceph_msg_data_cursor_init(&cursor, msg, data_len(msg));
+               init_sgs_cursor(&cur_sg, &cursor, data_pad);
+       }
+       WARN_ON(!sg_is_last(cur_sg));
+       sg_set_buf(cur_sg, epilogue,
+                  CEPH_GCM_BLOCK_LEN + (add_tag ? CEPH_GCM_TAG_LEN : 0));
+       return 0;
+ }
+ static int decrypt_preamble(struct ceph_connection *con)
+ {
+       struct scatterlist sg;
+       sg_init_one(&sg, con->v2.in_buf, CEPH_PREAMBLE_SECURE_LEN);
+       return gcm_crypt(con, false, &sg, &sg, CEPH_PREAMBLE_SECURE_LEN);
+ }
+ static int decrypt_control_remainder(struct ceph_connection *con)
+ {
+       int ctrl_len = con->v2.in_desc.fd_lens[0];
+       int rem_len = ctrl_len - CEPH_PREAMBLE_INLINE_LEN;
+       int pt_len = padding_len(rem_len) + CEPH_GCM_TAG_LEN;
+       struct scatterlist sgs[2];
+       WARN_ON(con->v2.in_kvecs[0].iov_len != rem_len);
+       WARN_ON(con->v2.in_kvecs[1].iov_len != pt_len);
+       sg_init_table(sgs, 2);
+       sg_set_buf(&sgs[0], con->v2.in_kvecs[0].iov_base, rem_len);
+       sg_set_buf(&sgs[1], con->v2.in_buf, pt_len);
+       return gcm_crypt(con, false, sgs, sgs,
+                        padded_len(rem_len) + CEPH_GCM_TAG_LEN);
+ }
+ static int decrypt_message(struct ceph_connection *con)
+ {
+       struct sg_table sgt = {};
+       int ret;
+       ret = setup_message_sgs(&sgt, con->in_msg, FRONT_PAD(con->v2.in_buf),
+                       MIDDLE_PAD(con->v2.in_buf), DATA_PAD(con->v2.in_buf),
+                       con->v2.in_buf, true);
+       if (ret)
+               goto out;
+       ret = gcm_crypt(con, false, sgt.sgl, sgt.sgl,
+                       tail_onwire_len(con->in_msg, true));
+ out:
+       sg_free_table(&sgt);
+       return ret;
+ }
+ static int prepare_banner(struct ceph_connection *con)
+ {
+       int buf_len = CEPH_BANNER_V2_LEN + 2 + 8 + 8;
+       void *buf, *p;
+       buf = alloc_conn_buf(con, buf_len);
+       if (!buf)
+               return -ENOMEM;
+       p = buf;
+       ceph_encode_copy(&p, CEPH_BANNER_V2, CEPH_BANNER_V2_LEN);
+       ceph_encode_16(&p, sizeof(u64) + sizeof(u64));
+       ceph_encode_64(&p, CEPH_MSGR2_SUPPORTED_FEATURES);
+       ceph_encode_64(&p, CEPH_MSGR2_REQUIRED_FEATURES);
+       WARN_ON(p != buf + buf_len);
+       add_out_kvec(con, buf, buf_len);
+       add_out_sign_kvec(con, buf, buf_len);
+       ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
+       return 0;
+ }
+ /*
+  * base:
+  *   preamble
+  *   control body (ctrl_len bytes)
+  *   space for control crc
+  *
+  * extdata (optional):
+  *   control body (extdata_len bytes)
+  *
+  * Compute control crc and gather base and extdata into:
+  *
+  *   preamble
+  *   control body (ctrl_len + extdata_len bytes)
+  *   control crc
+  *
+  * Preamble should already be encoded at the start of base.
+  */
+ static void prepare_head_plain(struct ceph_connection *con, void *base,
+                              int ctrl_len, void *extdata, int extdata_len,
+                              bool to_be_signed)
+ {
+       int base_len = CEPH_PREAMBLE_LEN + ctrl_len + CEPH_CRC_LEN;
+       void *crcp = base + base_len - CEPH_CRC_LEN;
+       u32 crc;
+       crc = crc32c(-1, CTRL_BODY(base), ctrl_len);
+       if (extdata_len)
+               crc = crc32c(crc, extdata, extdata_len);
+       put_unaligned_le32(crc, crcp);
+       if (!extdata_len) {
+               add_out_kvec(con, base, base_len);
+               if (to_be_signed)
+                       add_out_sign_kvec(con, base, base_len);
+               return;
+       }
+       add_out_kvec(con, base, crcp - base);
+       add_out_kvec(con, extdata, extdata_len);
+       add_out_kvec(con, crcp, CEPH_CRC_LEN);
+       if (to_be_signed) {
+               add_out_sign_kvec(con, base, crcp - base);
+               add_out_sign_kvec(con, extdata, extdata_len);
+               add_out_sign_kvec(con, crcp, CEPH_CRC_LEN);
+       }
+ }
+ static int prepare_head_secure_small(struct ceph_connection *con,
+                                    void *base, int ctrl_len)
+ {
+       struct scatterlist sg;
+       int ret;
+       /* inline buffer padding? */
+       if (ctrl_len < CEPH_PREAMBLE_INLINE_LEN)
+               memset(CTRL_BODY(base) + ctrl_len, 0,
+                      CEPH_PREAMBLE_INLINE_LEN - ctrl_len);
+       sg_init_one(&sg, base, CEPH_PREAMBLE_SECURE_LEN);
+       ret = gcm_crypt(con, true, &sg, &sg,
+                       CEPH_PREAMBLE_SECURE_LEN - CEPH_GCM_TAG_LEN);
+       if (ret)
+               return ret;
+       add_out_kvec(con, base, CEPH_PREAMBLE_SECURE_LEN);
+       return 0;
+ }
+ /*
+  * base:
+  *   preamble
+  *   control body (ctrl_len bytes)
+  *   space for padding, if needed
+  *   space for control remainder auth tag
+  *   space for preamble auth tag
+  *
+  * Encrypt preamble and the inline portion, then encrypt the remainder
+  * and gather into:
+  *
+  *   preamble
+  *   control body (48 bytes)
+  *   preamble auth tag
+  *   control body (ctrl_len - 48 bytes)
+  *   zero padding, if needed
+  *   control remainder auth tag
+  *
+  * Preamble should already be encoded at the start of base.
+  */
+ static int prepare_head_secure_big(struct ceph_connection *con,
+                                  void *base, int ctrl_len)
+ {
+       int rem_len = ctrl_len - CEPH_PREAMBLE_INLINE_LEN;
+       void *rem = CTRL_BODY(base) + CEPH_PREAMBLE_INLINE_LEN;
+       void *rem_tag = rem + padded_len(rem_len);
+       void *pmbl_tag = rem_tag + CEPH_GCM_TAG_LEN;
+       struct scatterlist sgs[2];
+       int ret;
+       sg_init_table(sgs, 2);
+       sg_set_buf(&sgs[0], base, rem - base);
+       sg_set_buf(&sgs[1], pmbl_tag, CEPH_GCM_TAG_LEN);
+       ret = gcm_crypt(con, true, sgs, sgs, rem - base);
+       if (ret)
+               return ret;
+       /* control remainder padding? */
+       if (need_padding(rem_len))
+               memset(rem + rem_len, 0, padding_len(rem_len));
+       sg_init_one(&sgs[0], rem, pmbl_tag - rem);
+       ret = gcm_crypt(con, true, sgs, sgs, rem_tag - rem);
+       if (ret)
+               return ret;
+       add_out_kvec(con, base, rem - base);
+       add_out_kvec(con, pmbl_tag, CEPH_GCM_TAG_LEN);
+       add_out_kvec(con, rem, pmbl_tag - rem);
+       return 0;
+ }
+ static int __prepare_control(struct ceph_connection *con, int tag,
+                            void *base, int ctrl_len, void *extdata,
+                            int extdata_len, bool to_be_signed)
+ {
+       int total_len = ctrl_len + extdata_len;
+       struct ceph_frame_desc desc;
+       int ret;
+       dout("%s con %p tag %d len %d (%d+%d)\n", __func__, con, tag,
+            total_len, ctrl_len, extdata_len);
+       /* extdata may be vmalloc'ed but not base */
+       if (WARN_ON(is_vmalloc_addr(base) || !ctrl_len))
+               return -EINVAL;
+       init_frame_desc(&desc, tag, &total_len, 1);
+       encode_preamble(&desc, base);
+       if (con_secure(con)) {
+               if (WARN_ON(extdata_len || to_be_signed))
+                       return -EINVAL;
+               if (ctrl_len <= CEPH_PREAMBLE_INLINE_LEN)
+                       /* fully inlined, inline buffer may need padding */
+                       ret = prepare_head_secure_small(con, base, ctrl_len);
+               else
+                       /* partially inlined, inline buffer is full */
+                       ret = prepare_head_secure_big(con, base, ctrl_len);
+               if (ret)
+                       return ret;
+       } else {
+               prepare_head_plain(con, base, ctrl_len, extdata, extdata_len,
+                                  to_be_signed);
+       }
+       ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
+       return 0;
+ }
+ static int prepare_control(struct ceph_connection *con, int tag,
+                          void *base, int ctrl_len)
+ {
+       return __prepare_control(con, tag, base, ctrl_len, NULL, 0, false);
+ }
+ static int prepare_hello(struct ceph_connection *con)
+ {
+       void *buf, *p;
+       int ctrl_len;
+       ctrl_len = 1 + ceph_entity_addr_encoding_len(&con->peer_addr);
+       buf = alloc_conn_buf(con, head_onwire_len(ctrl_len, false));
+       if (!buf)
+               return -ENOMEM;
+       p = CTRL_BODY(buf);
+       ceph_encode_8(&p, CEPH_ENTITY_TYPE_CLIENT);
+       ceph_encode_entity_addr(&p, &con->peer_addr);
+       WARN_ON(p != CTRL_BODY(buf) + ctrl_len);
+       return __prepare_control(con, FRAME_TAG_HELLO, buf, ctrl_len,
+                                NULL, 0, true);
+ }
+ /* so that head_onwire_len(AUTH_BUF_LEN, false) is 512 */
+ #define AUTH_BUF_LEN  (512 - CEPH_CRC_LEN - CEPH_PREAMBLE_PLAIN_LEN)
+ static int prepare_auth_request(struct ceph_connection *con)
+ {
+       void *authorizer, *authorizer_copy;
+       int ctrl_len, authorizer_len;
+       void *buf;
+       int ret;
+       ctrl_len = AUTH_BUF_LEN;
+       buf = alloc_conn_buf(con, head_onwire_len(ctrl_len, false));
+       if (!buf)
+               return -ENOMEM;
+       mutex_unlock(&con->mutex);
+       ret = con->ops->get_auth_request(con, CTRL_BODY(buf), &ctrl_len,
+                                        &authorizer, &authorizer_len);
+       mutex_lock(&con->mutex);
+       if (con->state != CEPH_CON_S_V2_HELLO) {
+               dout("%s con %p state changed to %d\n", __func__, con,
+                    con->state);
+               return -EAGAIN;
+       }
+       dout("%s con %p get_auth_request ret %d\n", __func__, con, ret);
+       if (ret)
+               return ret;
+       authorizer_copy = alloc_conn_buf(con, authorizer_len);
+       if (!authorizer_copy)
+               return -ENOMEM;
+       memcpy(authorizer_copy, authorizer, authorizer_len);
+       return __prepare_control(con, FRAME_TAG_AUTH_REQUEST, buf, ctrl_len,
+                                authorizer_copy, authorizer_len, true);
+ }
+ static int prepare_auth_request_more(struct ceph_connection *con,
+                                    void *reply, int reply_len)
+ {
+       int ctrl_len, authorizer_len;
+       void *authorizer;
+       void *buf;
+       int ret;
+       ctrl_len = AUTH_BUF_LEN;
+       buf = alloc_conn_buf(con, head_onwire_len(ctrl_len, false));
+       if (!buf)
+               return -ENOMEM;
+       mutex_unlock(&con->mutex);
+       ret = con->ops->handle_auth_reply_more(con, reply, reply_len,
+                                              CTRL_BODY(buf), &ctrl_len,
+                                              &authorizer, &authorizer_len);
+       mutex_lock(&con->mutex);
+       if (con->state != CEPH_CON_S_V2_AUTH) {
+               dout("%s con %p state changed to %d\n", __func__, con,
+                    con->state);
+               return -EAGAIN;
+       }
+       dout("%s con %p handle_auth_reply_more ret %d\n", __func__, con, ret);
+       if (ret)
+               return ret;
+       return __prepare_control(con, FRAME_TAG_AUTH_REQUEST_MORE, buf,
+                                ctrl_len, authorizer, authorizer_len, true);
+ }
+ static int prepare_auth_signature(struct ceph_connection *con)
+ {
+       void *buf;
+       int ret;
+       buf = alloc_conn_buf(con, head_onwire_len(SHA256_DIGEST_SIZE, false));
+       if (!buf)
+               return -ENOMEM;
+       ret = hmac_sha256(con, con->v2.in_sign_kvecs, con->v2.in_sign_kvec_cnt,
+                         CTRL_BODY(buf));
+       if (ret)
+               return ret;
+       return prepare_control(con, FRAME_TAG_AUTH_SIGNATURE, buf,
+                              SHA256_DIGEST_SIZE);
+ }
+ static int prepare_client_ident(struct ceph_connection *con)
+ {
+       struct ceph_entity_addr *my_addr = &con->msgr->inst.addr;
+       struct ceph_client *client = from_msgr(con->msgr);
+       u64 global_id = ceph_client_gid(client);
+       void *buf, *p;
+       int ctrl_len;
+       WARN_ON(con->v2.server_cookie);
+       WARN_ON(con->v2.connect_seq);
+       WARN_ON(con->v2.peer_global_seq);
+       if (!con->v2.client_cookie) {
+               do {
+                       get_random_bytes(&con->v2.client_cookie,
+                                        sizeof(con->v2.client_cookie));
+               } while (!con->v2.client_cookie);
+               dout("%s con %p generated cookie 0x%llx\n", __func__, con,
+                    con->v2.client_cookie);
+       } else {
+               dout("%s con %p cookie already set 0x%llx\n", __func__, con,
+                    con->v2.client_cookie);
+       }
+       dout("%s con %p my_addr %s/%u peer_addr %s/%u global_id %llu global_seq %llu features 0x%llx required_features 0x%llx cookie 0x%llx\n",
+            __func__, con, ceph_pr_addr(my_addr), le32_to_cpu(my_addr->nonce),
+            ceph_pr_addr(&con->peer_addr), le32_to_cpu(con->peer_addr.nonce),
+            global_id, con->v2.global_seq, client->supported_features,
+            client->required_features, con->v2.client_cookie);
+       ctrl_len = 1 + 4 + ceph_entity_addr_encoding_len(my_addr) +
+                  ceph_entity_addr_encoding_len(&con->peer_addr) + 6 * 8;
+       buf = alloc_conn_buf(con, head_onwire_len(ctrl_len, con_secure(con)));
+       if (!buf)
+               return -ENOMEM;
+       p = CTRL_BODY(buf);
+       ceph_encode_8(&p, 2);  /* addrvec marker */
+       ceph_encode_32(&p, 1);  /* addr_cnt */
+       ceph_encode_entity_addr(&p, my_addr);
+       ceph_encode_entity_addr(&p, &con->peer_addr);
+       ceph_encode_64(&p, global_id);
+       ceph_encode_64(&p, con->v2.global_seq);
+       ceph_encode_64(&p, client->supported_features);
+       ceph_encode_64(&p, client->required_features);
+       ceph_encode_64(&p, 0);  /* flags */
+       ceph_encode_64(&p, con->v2.client_cookie);
+       WARN_ON(p != CTRL_BODY(buf) + ctrl_len);
+       return prepare_control(con, FRAME_TAG_CLIENT_IDENT, buf, ctrl_len);
+ }
+ static int prepare_session_reconnect(struct ceph_connection *con)
+ {
+       struct ceph_entity_addr *my_addr = &con->msgr->inst.addr;
+       void *buf, *p;
+       int ctrl_len;
+       WARN_ON(!con->v2.client_cookie);
+       WARN_ON(!con->v2.server_cookie);
+       WARN_ON(!con->v2.connect_seq);
+       WARN_ON(!con->v2.peer_global_seq);
+       dout("%s con %p my_addr %s/%u client_cookie 0x%llx server_cookie 0x%llx global_seq %llu connect_seq %llu in_seq %llu\n",
+            __func__, con, ceph_pr_addr(my_addr), le32_to_cpu(my_addr->nonce),
+            con->v2.client_cookie, con->v2.server_cookie, con->v2.global_seq,
+            con->v2.connect_seq, con->in_seq);
+       ctrl_len = 1 + 4 + ceph_entity_addr_encoding_len(my_addr) + 5 * 8;
+       buf = alloc_conn_buf(con, head_onwire_len(ctrl_len, con_secure(con)));
+       if (!buf)
+               return -ENOMEM;
+       p = CTRL_BODY(buf);
+       ceph_encode_8(&p, 2);  /* entity_addrvec_t marker */
+       ceph_encode_32(&p, 1);  /* my_addrs len */
+       ceph_encode_entity_addr(&p, my_addr);
+       ceph_encode_64(&p, con->v2.client_cookie);
+       ceph_encode_64(&p, con->v2.server_cookie);
+       ceph_encode_64(&p, con->v2.global_seq);
+       ceph_encode_64(&p, con->v2.connect_seq);
+       ceph_encode_64(&p, con->in_seq);
+       WARN_ON(p != CTRL_BODY(buf) + ctrl_len);
+       return prepare_control(con, FRAME_TAG_SESSION_RECONNECT, buf, ctrl_len);
+ }
+ static int prepare_keepalive2(struct ceph_connection *con)
+ {
+       struct ceph_timespec *ts = CTRL_BODY(con->v2.out_buf);
+       struct timespec64 now;
+       ktime_get_real_ts64(&now);
+       dout("%s con %p timestamp %lld.%09ld\n", __func__, con, now.tv_sec,
+            now.tv_nsec);
+       ceph_encode_timespec64(ts, &now);
+       reset_out_kvecs(con);
+       return prepare_control(con, FRAME_TAG_KEEPALIVE2, con->v2.out_buf,
+                              sizeof(struct ceph_timespec));
+ }
+ static int prepare_ack(struct ceph_connection *con)
+ {
+       void *p;
+       dout("%s con %p in_seq_acked %llu -> %llu\n", __func__, con,
+            con->in_seq_acked, con->in_seq);
+       con->in_seq_acked = con->in_seq;
+       p = CTRL_BODY(con->v2.out_buf);
+       ceph_encode_64(&p, con->in_seq_acked);
+       reset_out_kvecs(con);
+       return prepare_control(con, FRAME_TAG_ACK, con->v2.out_buf, 8);
+ }
+ static void prepare_epilogue_plain(struct ceph_connection *con, bool aborted)
+ {
+       dout("%s con %p msg %p aborted %d crcs %u %u %u\n", __func__, con,
+            con->out_msg, aborted, con->v2.out_epil.front_crc,
+            con->v2.out_epil.middle_crc, con->v2.out_epil.data_crc);
+       encode_epilogue_plain(con, aborted);
+       add_out_kvec(con, &con->v2.out_epil, CEPH_EPILOGUE_PLAIN_LEN);
+ }
+ /*
+  * For "used" empty segments, crc is -1.  For unused (trailing)
+  * segments, crc is 0.
+  */
+ static void prepare_message_plain(struct ceph_connection *con)
+ {
+       struct ceph_msg *msg = con->out_msg;
+       prepare_head_plain(con, con->v2.out_buf,
+                          sizeof(struct ceph_msg_header2), NULL, 0, false);
+       if (!front_len(msg) && !middle_len(msg)) {
+               if (!data_len(msg)) {
+                       /*
+                        * Empty message: once the head is written,
+                        * we are done -- there is no epilogue.
+                        */
+                       con->v2.out_state = OUT_S_FINISH_MESSAGE;
+                       return;
+               }
+               con->v2.out_epil.front_crc = -1;
+               con->v2.out_epil.middle_crc = -1;
+               con->v2.out_state = OUT_S_QUEUE_DATA;
+               return;
+       }
+       if (front_len(msg)) {
+               con->v2.out_epil.front_crc = crc32c(-1, msg->front.iov_base,
+                                                   front_len(msg));
+               add_out_kvec(con, msg->front.iov_base, front_len(msg));
+       } else {
+               /* middle (at least) is there, checked above */
+               con->v2.out_epil.front_crc = -1;
+       }
+       if (middle_len(msg)) {
+               con->v2.out_epil.middle_crc =
+                       crc32c(-1, msg->middle->vec.iov_base, middle_len(msg));
+               add_out_kvec(con, msg->middle->vec.iov_base, middle_len(msg));
+       } else {
+               con->v2.out_epil.middle_crc = data_len(msg) ? -1 : 0;
+       }
+       if (data_len(msg)) {
+               con->v2.out_state = OUT_S_QUEUE_DATA;
+       } else {
+               con->v2.out_epil.data_crc = 0;
+               prepare_epilogue_plain(con, false);
+               con->v2.out_state = OUT_S_FINISH_MESSAGE;
+       }
+ }
+ /*
+  * Unfortunately the kernel crypto API doesn't support streaming
+  * (piecewise) operation for AEAD algorithms, so we can't get away
+  * with a fixed size buffer and a couple sgs.  Instead, we have to
+  * allocate pages for the entire tail of the message (currently up
+  * to ~32M) and two sgs arrays (up to ~256K each)...
+  */
+ static int prepare_message_secure(struct ceph_connection *con)
+ {
+       void *zerop = page_address(ceph_zero_page);
+       struct sg_table enc_sgt = {};
+       struct sg_table sgt = {};
+       struct page **enc_pages;
+       int enc_page_cnt;
+       int tail_len;
+       int ret;
+       ret = prepare_head_secure_small(con, con->v2.out_buf,
+                                       sizeof(struct ceph_msg_header2));
+       if (ret)
+               return ret;
+       tail_len = tail_onwire_len(con->out_msg, true);
+       if (!tail_len) {
+               /*
+                * Empty message: once the head is written,
+                * we are done -- there is no epilogue.
+                */
+               con->v2.out_state = OUT_S_FINISH_MESSAGE;
+               return 0;
+       }
+       encode_epilogue_secure(con, false);
+       ret = setup_message_sgs(&sgt, con->out_msg, zerop, zerop, zerop,
+                               &con->v2.out_epil, false);
+       if (ret)
+               goto out;
+       enc_page_cnt = calc_pages_for(0, tail_len);
+       enc_pages = ceph_alloc_page_vector(enc_page_cnt, GFP_NOIO);
+       if (IS_ERR(enc_pages)) {
+               ret = PTR_ERR(enc_pages);
+               goto out;
+       }
+       WARN_ON(con->v2.out_enc_pages || con->v2.out_enc_page_cnt);
+       con->v2.out_enc_pages = enc_pages;
+       con->v2.out_enc_page_cnt = enc_page_cnt;
+       con->v2.out_enc_resid = tail_len;
+       con->v2.out_enc_i = 0;
+       ret = sg_alloc_table_from_pages(&enc_sgt, enc_pages, enc_page_cnt,
+                                       0, tail_len, GFP_NOIO);
+       if (ret)
+               goto out;
+       ret = gcm_crypt(con, true, sgt.sgl, enc_sgt.sgl,
+                       tail_len - CEPH_GCM_TAG_LEN);
+       if (ret)
+               goto out;
+       dout("%s con %p msg %p sg_cnt %d enc_page_cnt %d\n", __func__, con,
+            con->out_msg, sgt.orig_nents, enc_page_cnt);
+       con->v2.out_state = OUT_S_QUEUE_ENC_PAGE;
+ out:
+       sg_free_table(&sgt);
+       sg_free_table(&enc_sgt);
+       return ret;
+ }
+ static int prepare_message(struct ceph_connection *con)
+ {
+       int lens[] = {
+               sizeof(struct ceph_msg_header2),
+               front_len(con->out_msg),
+               middle_len(con->out_msg),
+               data_len(con->out_msg)
+       };
+       struct ceph_frame_desc desc;
+       int ret;
+       dout("%s con %p msg %p logical %d+%d+%d+%d\n", __func__, con,
+            con->out_msg, lens[0], lens[1], lens[2], lens[3]);
+       if (con->in_seq > con->in_seq_acked) {
+               dout("%s con %p in_seq_acked %llu -> %llu\n", __func__, con,
+                    con->in_seq_acked, con->in_seq);
+               con->in_seq_acked = con->in_seq;
+       }
+       reset_out_kvecs(con);
+       init_frame_desc(&desc, FRAME_TAG_MESSAGE, lens, 4);
+       encode_preamble(&desc, con->v2.out_buf);
+       fill_header2(CTRL_BODY(con->v2.out_buf), &con->out_msg->hdr,
+                    con->in_seq_acked);
+       if (con_secure(con)) {
+               ret = prepare_message_secure(con);
+               if (ret)
+                       return ret;
+       } else {
+               prepare_message_plain(con);
+       }
+       ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
+       return 0;
+ }
+ static int prepare_read_banner_prefix(struct ceph_connection *con)
+ {
+       void *buf;
+       buf = alloc_conn_buf(con, CEPH_BANNER_V2_PREFIX_LEN);
+       if (!buf)
+               return -ENOMEM;
+       reset_in_kvecs(con);
+       add_in_kvec(con, buf, CEPH_BANNER_V2_PREFIX_LEN);
+       add_in_sign_kvec(con, buf, CEPH_BANNER_V2_PREFIX_LEN);
+       con->state = CEPH_CON_S_V2_BANNER_PREFIX;
+       return 0;
+ }
+ static int prepare_read_banner_payload(struct ceph_connection *con,
+                                      int payload_len)
+ {
+       void *buf;
+       buf = alloc_conn_buf(con, payload_len);
+       if (!buf)
+               return -ENOMEM;
+       reset_in_kvecs(con);
+       add_in_kvec(con, buf, payload_len);
+       add_in_sign_kvec(con, buf, payload_len);
+       con->state = CEPH_CON_S_V2_BANNER_PAYLOAD;
+       return 0;
+ }
+ static void prepare_read_preamble(struct ceph_connection *con)
+ {
+       reset_in_kvecs(con);
+       add_in_kvec(con, con->v2.in_buf,
+                   con_secure(con) ? CEPH_PREAMBLE_SECURE_LEN :
+                                     CEPH_PREAMBLE_PLAIN_LEN);
+       con->v2.in_state = IN_S_HANDLE_PREAMBLE;
+ }
+ static int prepare_read_control(struct ceph_connection *con)
+ {
+       int ctrl_len = con->v2.in_desc.fd_lens[0];
+       int head_len;
+       void *buf;
+       reset_in_kvecs(con);
+       if (con->state == CEPH_CON_S_V2_HELLO ||
+           con->state == CEPH_CON_S_V2_AUTH) {
+               head_len = head_onwire_len(ctrl_len, false);
+               buf = alloc_conn_buf(con, head_len);
+               if (!buf)
+                       return -ENOMEM;
+               /* preserve preamble */
+               memcpy(buf, con->v2.in_buf, CEPH_PREAMBLE_LEN);
+               add_in_kvec(con, CTRL_BODY(buf), ctrl_len);
+               add_in_kvec(con, CTRL_BODY(buf) + ctrl_len, CEPH_CRC_LEN);
+               add_in_sign_kvec(con, buf, head_len);
+       } else {
+               if (ctrl_len > CEPH_PREAMBLE_INLINE_LEN) {
+                       buf = alloc_conn_buf(con, ctrl_len);
+                       if (!buf)
+                               return -ENOMEM;
+                       add_in_kvec(con, buf, ctrl_len);
+               } else {
+                       add_in_kvec(con, CTRL_BODY(con->v2.in_buf), ctrl_len);
+               }
+               add_in_kvec(con, con->v2.in_buf, CEPH_CRC_LEN);
+       }
+       con->v2.in_state = IN_S_HANDLE_CONTROL;
+       return 0;
+ }
+ static int prepare_read_control_remainder(struct ceph_connection *con)
+ {
+       int ctrl_len = con->v2.in_desc.fd_lens[0];
+       int rem_len = ctrl_len - CEPH_PREAMBLE_INLINE_LEN;
+       void *buf;
+       buf = alloc_conn_buf(con, ctrl_len);
+       if (!buf)
+               return -ENOMEM;
+       memcpy(buf, CTRL_BODY(con->v2.in_buf), CEPH_PREAMBLE_INLINE_LEN);
+       reset_in_kvecs(con);
+       add_in_kvec(con, buf + CEPH_PREAMBLE_INLINE_LEN, rem_len);
+       add_in_kvec(con, con->v2.in_buf,
+                   padding_len(rem_len) + CEPH_GCM_TAG_LEN);
+       con->v2.in_state = IN_S_HANDLE_CONTROL_REMAINDER;
+       return 0;
+ }
+ static void prepare_read_data(struct ceph_connection *con)
+ {
+       struct bio_vec bv;
+       if (!con_secure(con))
+               con->in_data_crc = -1;
+       ceph_msg_data_cursor_init(&con->v2.in_cursor, con->in_msg,
+                                 data_len(con->in_msg));
+       get_bvec_at(&con->v2.in_cursor, &bv);
+       set_in_bvec(con, &bv);
+       con->v2.in_state = IN_S_PREPARE_READ_DATA_CONT;
+ }
+ static void prepare_read_data_cont(struct ceph_connection *con)
+ {
+       struct bio_vec bv;
+       if (!con_secure(con))
+               con->in_data_crc = ceph_crc32c_page(con->in_data_crc,
+                                                   con->v2.in_bvec.bv_page,
+                                                   con->v2.in_bvec.bv_offset,
+                                                   con->v2.in_bvec.bv_len);
+       ceph_msg_data_advance(&con->v2.in_cursor, con->v2.in_bvec.bv_len);
+       if (con->v2.in_cursor.total_resid) {
+               get_bvec_at(&con->v2.in_cursor, &bv);
+               set_in_bvec(con, &bv);
+               WARN_ON(con->v2.in_state != IN_S_PREPARE_READ_DATA_CONT);
+               return;
+       }
+       /*
+        * We've read all data.  Prepare to read data padding (if any)
+        * and epilogue.
+        */
+       reset_in_kvecs(con);
+       if (con_secure(con)) {
+               if (need_padding(data_len(con->in_msg)))
+                       add_in_kvec(con, DATA_PAD(con->v2.in_buf),
+                                   padding_len(data_len(con->in_msg)));
+               add_in_kvec(con, con->v2.in_buf, CEPH_EPILOGUE_SECURE_LEN);
+       } else {
+               add_in_kvec(con, con->v2.in_buf, CEPH_EPILOGUE_PLAIN_LEN);
+       }
+       con->v2.in_state = IN_S_HANDLE_EPILOGUE;
+ }
+ static void __finish_skip(struct ceph_connection *con)
+ {
+       con->in_seq++;
+       prepare_read_preamble(con);
+ }
+ static void prepare_skip_message(struct ceph_connection *con)
+ {
+       struct ceph_frame_desc *desc = &con->v2.in_desc;
+       int tail_len;
+       dout("%s con %p %d+%d+%d\n", __func__, con, desc->fd_lens[1],
+            desc->fd_lens[2], desc->fd_lens[3]);
+       tail_len = __tail_onwire_len(desc->fd_lens[1], desc->fd_lens[2],
+                                    desc->fd_lens[3], con_secure(con));
+       if (!tail_len) {
+               __finish_skip(con);
+       } else {
+               set_in_skip(con, tail_len);
+               con->v2.in_state = IN_S_FINISH_SKIP;
+       }
+ }
+ static int process_banner_prefix(struct ceph_connection *con)
+ {
+       int payload_len;
+       void *p;
+       WARN_ON(con->v2.in_kvecs[0].iov_len != CEPH_BANNER_V2_PREFIX_LEN);
+       p = con->v2.in_kvecs[0].iov_base;
+       if (memcmp(p, CEPH_BANNER_V2, CEPH_BANNER_V2_LEN)) {
+               if (!memcmp(p, CEPH_BANNER, CEPH_BANNER_LEN))
+                       con->error_msg = "server is speaking msgr1 protocol";
+               else
+                       con->error_msg = "protocol error, bad banner";
+               return -EINVAL;
+       }
+       p += CEPH_BANNER_V2_LEN;
+       payload_len = ceph_decode_16(&p);
+       dout("%s con %p payload_len %d\n", __func__, con, payload_len);
+       return prepare_read_banner_payload(con, payload_len);
+ }
+ static int process_banner_payload(struct ceph_connection *con)
+ {
+       void *end = con->v2.in_kvecs[0].iov_base + con->v2.in_kvecs[0].iov_len;
+       u64 feat = CEPH_MSGR2_SUPPORTED_FEATURES;
+       u64 req_feat = CEPH_MSGR2_REQUIRED_FEATURES;
+       u64 server_feat, server_req_feat;
+       void *p;
+       int ret;
+       p = con->v2.in_kvecs[0].iov_base;
+       ceph_decode_64_safe(&p, end, server_feat, bad);
+       ceph_decode_64_safe(&p, end, server_req_feat, bad);
+       dout("%s con %p server_feat 0x%llx server_req_feat 0x%llx\n",
+            __func__, con, server_feat, server_req_feat);
+       if (req_feat & ~server_feat) {
+               pr_err("msgr2 feature set mismatch: my required > server's supported 0x%llx, need 0x%llx\n",
+                      server_feat, req_feat & ~server_feat);
+               con->error_msg = "missing required protocol features";
+               return -EINVAL;
+       }
+       if (server_req_feat & ~feat) {
+               pr_err("msgr2 feature set mismatch: server's required > my supported 0x%llx, missing 0x%llx\n",
+                      feat, server_req_feat & ~feat);
+               con->error_msg = "missing required protocol features";
+               return -EINVAL;
+       }
+       /* no reset_out_kvecs() as our banner may still be pending */
+       ret = prepare_hello(con);
+       if (ret) {
+               pr_err("prepare_hello failed: %d\n", ret);
+               return ret;
+       }
+       con->state = CEPH_CON_S_V2_HELLO;
+       prepare_read_preamble(con);
+       return 0;
+ bad:
+       pr_err("failed to decode banner payload\n");
+       return -EINVAL;
+ }
+ static int process_hello(struct ceph_connection *con, void *p, void *end)
+ {
+       struct ceph_entity_addr *my_addr = &con->msgr->inst.addr;
+       struct ceph_entity_addr addr_for_me;
+       u8 entity_type;
+       int ret;
+       if (con->state != CEPH_CON_S_V2_HELLO) {
+               con->error_msg = "protocol error, unexpected hello";
+               return -EINVAL;
+       }
+       ceph_decode_8_safe(&p, end, entity_type, bad);
+       ret = ceph_decode_entity_addr(&p, end, &addr_for_me);
+       if (ret) {
+               pr_err("failed to decode addr_for_me: %d\n", ret);
+               return ret;
+       }
+       dout("%s con %p entity_type %d addr_for_me %s\n", __func__, con,
+            entity_type, ceph_pr_addr(&addr_for_me));
+       if (entity_type != con->peer_name.type) {
+               pr_err("bad peer type, want %d, got %d\n",
+                      con->peer_name.type, entity_type);
+               con->error_msg = "wrong peer at address";
+               return -EINVAL;
+       }
+       /*
+        * Set our address to the address our first peer (i.e. monitor)
+        * sees that we are connecting from.  If we are behind some sort
+        * of NAT and want to be identified by some private (not NATed)
+        * address, ip option should be used.
+        */
+       if (ceph_addr_is_blank(my_addr)) {
+               memcpy(&my_addr->in_addr, &addr_for_me.in_addr,
+                      sizeof(my_addr->in_addr));
+               ceph_addr_set_port(my_addr, 0);
+               dout("%s con %p set my addr %s, as seen by peer %s\n",
+                    __func__, con, ceph_pr_addr(my_addr),
+                    ceph_pr_addr(&con->peer_addr));
+       } else {
+               dout("%s con %p my addr already set %s\n",
+                    __func__, con, ceph_pr_addr(my_addr));
+       }
+       WARN_ON(ceph_addr_is_blank(my_addr) || ceph_addr_port(my_addr));
+       WARN_ON(my_addr->type != CEPH_ENTITY_ADDR_TYPE_ANY);
+       WARN_ON(!my_addr->nonce);
+       /* no reset_out_kvecs() as our hello may still be pending */
+       ret = prepare_auth_request(con);
+       if (ret) {
+               if (ret != -EAGAIN)
+                       pr_err("prepare_auth_request failed: %d\n", ret);
+               return ret;
+       }
+       con->state = CEPH_CON_S_V2_AUTH;
+       return 0;
+ bad:
+       pr_err("failed to decode hello\n");
+       return -EINVAL;
+ }
+ static int process_auth_bad_method(struct ceph_connection *con,
+                                  void *p, void *end)
+ {
+       int allowed_protos[8], allowed_modes[8];
+       int allowed_proto_cnt, allowed_mode_cnt;
+       int used_proto, result;
+       int ret;
+       int i;
+       if (con->state != CEPH_CON_S_V2_AUTH) {
+               con->error_msg = "protocol error, unexpected auth_bad_method";
+               return -EINVAL;
+       }
+       ceph_decode_32_safe(&p, end, used_proto, bad);
+       ceph_decode_32_safe(&p, end, result, bad);
+       dout("%s con %p used_proto %d result %d\n", __func__, con, used_proto,
+            result);
+       ceph_decode_32_safe(&p, end, allowed_proto_cnt, bad);
+       if (allowed_proto_cnt > ARRAY_SIZE(allowed_protos)) {
+               pr_err("allowed_protos too big %d\n", allowed_proto_cnt);
+               return -EINVAL;
+       }
+       for (i = 0; i < allowed_proto_cnt; i++) {
+               ceph_decode_32_safe(&p, end, allowed_protos[i], bad);
+               dout("%s con %p allowed_protos[%d] %d\n", __func__, con,
+                    i, allowed_protos[i]);
+       }
+       ceph_decode_32_safe(&p, end, allowed_mode_cnt, bad);
+       if (allowed_mode_cnt > ARRAY_SIZE(allowed_modes)) {
+               pr_err("allowed_modes too big %d\n", allowed_mode_cnt);
+               return -EINVAL;
+       }
+       for (i = 0; i < allowed_mode_cnt; i++) {
+               ceph_decode_32_safe(&p, end, allowed_modes[i], bad);
+               dout("%s con %p allowed_modes[%d] %d\n", __func__, con,
+                    i, allowed_modes[i]);
+       }
+       mutex_unlock(&con->mutex);
+       ret = con->ops->handle_auth_bad_method(con, used_proto, result,
+                                              allowed_protos,
+                                              allowed_proto_cnt,
+                                              allowed_modes,
+                                              allowed_mode_cnt);
+       mutex_lock(&con->mutex);
+       if (con->state != CEPH_CON_S_V2_AUTH) {
+               dout("%s con %p state changed to %d\n", __func__, con,
+                    con->state);
+               return -EAGAIN;
+       }
+       dout("%s con %p handle_auth_bad_method ret %d\n", __func__, con, ret);
+       return ret;
+ bad:
+       pr_err("failed to decode auth_bad_method\n");
+       return -EINVAL;
+ }
+ static int process_auth_reply_more(struct ceph_connection *con,
+                                  void *p, void *end)
+ {
+       int payload_len;
+       int ret;
+       if (con->state != CEPH_CON_S_V2_AUTH) {
+               con->error_msg = "protocol error, unexpected auth_reply_more";
+               return -EINVAL;
+       }
+       ceph_decode_32_safe(&p, end, payload_len, bad);
+       ceph_decode_need(&p, end, payload_len, bad);
+       dout("%s con %p payload_len %d\n", __func__, con, payload_len);
+       reset_out_kvecs(con);
+       ret = prepare_auth_request_more(con, p, payload_len);
+       if (ret) {
+               if (ret != -EAGAIN)
+                       pr_err("prepare_auth_request_more failed: %d\n", ret);
+               return ret;
+       }
+       return 0;
+ bad:
+       pr_err("failed to decode auth_reply_more\n");
+       return -EINVAL;
+ }
+ static int process_auth_done(struct ceph_connection *con, void *p, void *end)
+ {
+       u8 session_key[CEPH_KEY_LEN];
+       u8 con_secret[CEPH_MAX_CON_SECRET_LEN];
+       int session_key_len, con_secret_len;
+       int payload_len;
+       u64 global_id;
+       int ret;
+       if (con->state != CEPH_CON_S_V2_AUTH) {
+               con->error_msg = "protocol error, unexpected auth_done";
+               return -EINVAL;
+       }
+       ceph_decode_64_safe(&p, end, global_id, bad);
+       ceph_decode_32_safe(&p, end, con->v2.con_mode, bad);
+       ceph_decode_32_safe(&p, end, payload_len, bad);
+       dout("%s con %p global_id %llu con_mode %d payload_len %d\n",
+            __func__, con, global_id, con->v2.con_mode, payload_len);
+       mutex_unlock(&con->mutex);
+       session_key_len = 0;
+       con_secret_len = 0;
+       ret = con->ops->handle_auth_done(con, global_id, p, payload_len,
+                                        session_key, &session_key_len,
+                                        con_secret, &con_secret_len);
+       mutex_lock(&con->mutex);
+       if (con->state != CEPH_CON_S_V2_AUTH) {
+               dout("%s con %p state changed to %d\n", __func__, con,
+                    con->state);
+               return -EAGAIN;
+       }
+       dout("%s con %p handle_auth_done ret %d\n", __func__, con, ret);
+       if (ret)
+               return ret;
+       ret = setup_crypto(con, session_key, session_key_len, con_secret,
+                          con_secret_len);
+       if (ret)
+               return ret;
+       reset_out_kvecs(con);
+       ret = prepare_auth_signature(con);
+       if (ret) {
+               pr_err("prepare_auth_signature failed: %d\n", ret);
+               return ret;
+       }
+       con->state = CEPH_CON_S_V2_AUTH_SIGNATURE;
+       return 0;
+ bad:
+       pr_err("failed to decode auth_done\n");
+       return -EINVAL;
+ }
+ static int process_auth_signature(struct ceph_connection *con,
+                                 void *p, void *end)
+ {
+       u8 hmac[SHA256_DIGEST_SIZE];
+       int ret;
+       if (con->state != CEPH_CON_S_V2_AUTH_SIGNATURE) {
+               con->error_msg = "protocol error, unexpected auth_signature";
+               return -EINVAL;
+       }
+       ret = hmac_sha256(con, con->v2.out_sign_kvecs,
+                         con->v2.out_sign_kvec_cnt, hmac);
+       if (ret)
+               return ret;
+       ceph_decode_need(&p, end, SHA256_DIGEST_SIZE, bad);
+       if (crypto_memneq(p, hmac, SHA256_DIGEST_SIZE)) {
+               con->error_msg = "integrity error, bad auth signature";
+               return -EBADMSG;
+       }
+       dout("%s con %p auth signature ok\n", __func__, con);
+       /* no reset_out_kvecs() as our auth_signature may still be pending */
+       if (!con->v2.server_cookie) {
+               ret = prepare_client_ident(con);
+               if (ret) {
+                       pr_err("prepare_client_ident failed: %d\n", ret);
+                       return ret;
+               }
+               con->state = CEPH_CON_S_V2_SESSION_CONNECT;
+       } else {
+               ret = prepare_session_reconnect(con);
+               if (ret) {
+                       pr_err("prepare_session_reconnect failed: %d\n", ret);
+                       return ret;
+               }
+               con->state = CEPH_CON_S_V2_SESSION_RECONNECT;
+       }
+       return 0;
+ bad:
+       pr_err("failed to decode auth_signature\n");
+       return -EINVAL;
+ }
+ static int process_server_ident(struct ceph_connection *con,
+                               void *p, void *end)
+ {
+       struct ceph_client *client = from_msgr(con->msgr);
+       u64 features, required_features;
+       struct ceph_entity_addr addr;
+       u64 global_seq;
+       u64 global_id;
+       u64 cookie;
+       u64 flags;
+       int ret;
+       if (con->state != CEPH_CON_S_V2_SESSION_CONNECT) {
+               con->error_msg = "protocol error, unexpected server_ident";
+               return -EINVAL;
+       }
+       ret = ceph_decode_entity_addrvec(&p, end, true, &addr);
+       if (ret) {
+               pr_err("failed to decode server addrs: %d\n", ret);
+               return ret;
+       }
+       ceph_decode_64_safe(&p, end, global_id, bad);
+       ceph_decode_64_safe(&p, end, global_seq, bad);
+       ceph_decode_64_safe(&p, end, features, bad);
+       ceph_decode_64_safe(&p, end, required_features, bad);
+       ceph_decode_64_safe(&p, end, flags, bad);
+       ceph_decode_64_safe(&p, end, cookie, bad);
+       dout("%s con %p addr %s/%u global_id %llu global_seq %llu features 0x%llx required_features 0x%llx flags 0x%llx cookie 0x%llx\n",
+            __func__, con, ceph_pr_addr(&addr), le32_to_cpu(addr.nonce),
+            global_id, global_seq, features, required_features, flags, cookie);
+       /* is this who we intended to talk to? */
+       if (memcmp(&addr, &con->peer_addr, sizeof(con->peer_addr))) {
+               pr_err("bad peer addr/nonce, want %s/%u, got %s/%u\n",
+                      ceph_pr_addr(&con->peer_addr),
+                      le32_to_cpu(con->peer_addr.nonce),
+                      ceph_pr_addr(&addr), le32_to_cpu(addr.nonce));
+               con->error_msg = "wrong peer at address";
+               return -EINVAL;
+       }
+       if (client->required_features & ~features) {
+               pr_err("RADOS feature set mismatch: my required > server's supported 0x%llx, need 0x%llx\n",
+                      features, client->required_features & ~features);
+               con->error_msg = "missing required protocol features";
+               return -EINVAL;
+       }
+       /*
+        * Both name->type and name->num are set in ceph_con_open() but
+        * name->num may be bogus in the initial monmap.  name->type is
+        * verified in handle_hello().
+        */
+       WARN_ON(!con->peer_name.type);
+       con->peer_name.num = cpu_to_le64(global_id);
+       con->v2.peer_global_seq = global_seq;
+       con->peer_features = features;
+       WARN_ON(required_features & ~client->supported_features);
+       con->v2.server_cookie = cookie;
+       if (flags & CEPH_MSG_CONNECT_LOSSY) {
+               ceph_con_flag_set(con, CEPH_CON_F_LOSSYTX);
+               WARN_ON(con->v2.server_cookie);
+       } else {
+               WARN_ON(!con->v2.server_cookie);
+       }
+       clear_in_sign_kvecs(con);
+       clear_out_sign_kvecs(con);
+       free_conn_bufs(con);
+       con->delay = 0;  /* reset backoff memory */
+       con->state = CEPH_CON_S_OPEN;
+       con->v2.out_state = OUT_S_GET_NEXT;
+       return 0;
+ bad:
+       pr_err("failed to decode server_ident\n");
+       return -EINVAL;
+ }
+ static int process_ident_missing_features(struct ceph_connection *con,
+                                         void *p, void *end)
+ {
+       struct ceph_client *client = from_msgr(con->msgr);
+       u64 missing_features;
+       if (con->state != CEPH_CON_S_V2_SESSION_CONNECT) {
+               con->error_msg = "protocol error, unexpected ident_missing_features";
+               return -EINVAL;
+       }
+       ceph_decode_64_safe(&p, end, missing_features, bad);
+       pr_err("RADOS feature set mismatch: server's required > my supported 0x%llx, missing 0x%llx\n",
+              client->supported_features, missing_features);
+       con->error_msg = "missing required protocol features";
+       return -EINVAL;
+ bad:
+       pr_err("failed to decode ident_missing_features\n");
+       return -EINVAL;
+ }
+ static int process_session_reconnect_ok(struct ceph_connection *con,
+                                       void *p, void *end)
+ {
+       u64 seq;
+       if (con->state != CEPH_CON_S_V2_SESSION_RECONNECT) {
+               con->error_msg = "protocol error, unexpected session_reconnect_ok";
+               return -EINVAL;
+       }
+       ceph_decode_64_safe(&p, end, seq, bad);
+       dout("%s con %p seq %llu\n", __func__, con, seq);
+       ceph_con_discard_requeued(con, seq);
+       clear_in_sign_kvecs(con);
+       clear_out_sign_kvecs(con);
+       free_conn_bufs(con);
+       con->delay = 0;  /* reset backoff memory */
+       con->state = CEPH_CON_S_OPEN;
+       con->v2.out_state = OUT_S_GET_NEXT;
+       return 0;
+ bad:
+       pr_err("failed to decode session_reconnect_ok\n");
+       return -EINVAL;
+ }
+ static int process_session_retry(struct ceph_connection *con,
+                                void *p, void *end)
+ {
+       u64 connect_seq;
+       int ret;
+       if (con->state != CEPH_CON_S_V2_SESSION_RECONNECT) {
+               con->error_msg = "protocol error, unexpected session_retry";
+               return -EINVAL;
+       }
+       ceph_decode_64_safe(&p, end, connect_seq, bad);
+       dout("%s con %p connect_seq %llu\n", __func__, con, connect_seq);
+       WARN_ON(connect_seq <= con->v2.connect_seq);
+       con->v2.connect_seq = connect_seq + 1;
+       free_conn_bufs(con);
+       reset_out_kvecs(con);
+       ret = prepare_session_reconnect(con);
+       if (ret) {
+               pr_err("prepare_session_reconnect (cseq) failed: %d\n", ret);
+               return ret;
+       }
+       return 0;
+ bad:
+       pr_err("failed to decode session_retry\n");
+       return -EINVAL;
+ }
+ static int process_session_retry_global(struct ceph_connection *con,
+                                       void *p, void *end)
+ {
+       u64 global_seq;
+       int ret;
+       if (con->state != CEPH_CON_S_V2_SESSION_RECONNECT) {
+               con->error_msg = "protocol error, unexpected session_retry_global";
+               return -EINVAL;
+       }
+       ceph_decode_64_safe(&p, end, global_seq, bad);
+       dout("%s con %p global_seq %llu\n", __func__, con, global_seq);
+       WARN_ON(global_seq <= con->v2.global_seq);
+       con->v2.global_seq = ceph_get_global_seq(con->msgr, global_seq);
+       free_conn_bufs(con);
+       reset_out_kvecs(con);
+       ret = prepare_session_reconnect(con);
+       if (ret) {
+               pr_err("prepare_session_reconnect (gseq) failed: %d\n", ret);
+               return ret;
+       }
+       return 0;
+ bad:
+       pr_err("failed to decode session_retry_global\n");
+       return -EINVAL;
+ }
+ static int process_session_reset(struct ceph_connection *con,
+                                void *p, void *end)
+ {
+       bool full;
+       int ret;
+       if (con->state != CEPH_CON_S_V2_SESSION_RECONNECT) {
+               con->error_msg = "protocol error, unexpected session_reset";
+               return -EINVAL;
+       }
+       ceph_decode_8_safe(&p, end, full, bad);
+       if (!full) {
+               con->error_msg = "protocol error, bad session_reset";
+               return -EINVAL;
+       }
+       pr_info("%s%lld %s session reset\n", ENTITY_NAME(con->peer_name),
+               ceph_pr_addr(&con->peer_addr));
+       ceph_con_reset_session(con);
+       mutex_unlock(&con->mutex);
+       if (con->ops->peer_reset)
+               con->ops->peer_reset(con);
+       mutex_lock(&con->mutex);
+       if (con->state != CEPH_CON_S_V2_SESSION_RECONNECT) {
+               dout("%s con %p state changed to %d\n", __func__, con,
+                    con->state);
+               return -EAGAIN;
+       }
+       free_conn_bufs(con);
+       reset_out_kvecs(con);
+       ret = prepare_client_ident(con);
+       if (ret) {
+               pr_err("prepare_client_ident (rst) failed: %d\n", ret);
+               return ret;
+       }
+       con->state = CEPH_CON_S_V2_SESSION_CONNECT;
+       return 0;
+ bad:
+       pr_err("failed to decode session_reset\n");
+       return -EINVAL;
+ }
+ static int process_keepalive2_ack(struct ceph_connection *con,
+                                 void *p, void *end)
+ {
+       if (con->state != CEPH_CON_S_OPEN) {
+               con->error_msg = "protocol error, unexpected keepalive2_ack";
+               return -EINVAL;
+       }
+       ceph_decode_need(&p, end, sizeof(struct ceph_timespec), bad);
+       ceph_decode_timespec64(&con->last_keepalive_ack, p);
+       dout("%s con %p timestamp %lld.%09ld\n", __func__, con,
+            con->last_keepalive_ack.tv_sec, con->last_keepalive_ack.tv_nsec);
+       return 0;
+ bad:
+       pr_err("failed to decode keepalive2_ack\n");
+       return -EINVAL;
+ }
+ static int process_ack(struct ceph_connection *con, void *p, void *end)
+ {
+       u64 seq;
+       if (con->state != CEPH_CON_S_OPEN) {
+               con->error_msg = "protocol error, unexpected ack";
+               return -EINVAL;
+       }
+       ceph_decode_64_safe(&p, end, seq, bad);
+       dout("%s con %p seq %llu\n", __func__, con, seq);
+       ceph_con_discard_sent(con, seq);
+       return 0;
+ bad:
+       pr_err("failed to decode ack\n");
+       return -EINVAL;
+ }
+ static int process_control(struct ceph_connection *con, void *p, void *end)
+ {
+       int tag = con->v2.in_desc.fd_tag;
+       int ret;
+       dout("%s con %p tag %d len %d\n", __func__, con, tag, (int)(end - p));
+       switch (tag) {
+       case FRAME_TAG_HELLO:
+               ret = process_hello(con, p, end);
+               break;
+       case FRAME_TAG_AUTH_BAD_METHOD:
+               ret = process_auth_bad_method(con, p, end);
+               break;
+       case FRAME_TAG_AUTH_REPLY_MORE:
+               ret = process_auth_reply_more(con, p, end);
+               break;
+       case FRAME_TAG_AUTH_DONE:
+               ret = process_auth_done(con, p, end);
+               break;
+       case FRAME_TAG_AUTH_SIGNATURE:
+               ret = process_auth_signature(con, p, end);
+               break;
+       case FRAME_TAG_SERVER_IDENT:
+               ret = process_server_ident(con, p, end);
+               break;
+       case FRAME_TAG_IDENT_MISSING_FEATURES:
+               ret = process_ident_missing_features(con, p, end);
+               break;
+       case FRAME_TAG_SESSION_RECONNECT_OK:
+               ret = process_session_reconnect_ok(con, p, end);
+               break;
+       case FRAME_TAG_SESSION_RETRY:
+               ret = process_session_retry(con, p, end);
+               break;
+       case FRAME_TAG_SESSION_RETRY_GLOBAL:
+               ret = process_session_retry_global(con, p, end);
+               break;
+       case FRAME_TAG_SESSION_RESET:
+               ret = process_session_reset(con, p, end);
+               break;
+       case FRAME_TAG_KEEPALIVE2_ACK:
+               ret = process_keepalive2_ack(con, p, end);
+               break;
+       case FRAME_TAG_ACK:
+               ret = process_ack(con, p, end);
+               break;
+       default:
+               pr_err("bad tag %d\n", tag);
+               con->error_msg = "protocol error, bad tag";
+               return -EINVAL;
+       }
+       if (ret) {
+               dout("%s con %p error %d\n", __func__, con, ret);
+               return ret;
+       }
+       prepare_read_preamble(con);
+       return 0;
+ }
+ /*
+  * Return:
+  *   1 - con->in_msg set, read message
+  *   0 - skip message
+  *  <0 - error
+  */
+ static int process_message_header(struct ceph_connection *con,
+                                 void *p, void *end)
+ {
+       struct ceph_frame_desc *desc = &con->v2.in_desc;
+       struct ceph_msg_header2 *hdr2 = p;
+       struct ceph_msg_header hdr;
+       int skip;
+       int ret;
+       u64 seq;
+       /* verify seq# */
+       seq = le64_to_cpu(hdr2->seq);
+       if ((s64)seq - (s64)con->in_seq < 1) {
+               pr_info("%s%lld %s skipping old message: seq %llu, expected %llu\n",
+                       ENTITY_NAME(con->peer_name),
+                       ceph_pr_addr(&con->peer_addr),
+                       seq, con->in_seq + 1);
+               return 0;
+       }
+       if ((s64)seq - (s64)con->in_seq > 1) {
+               pr_err("bad seq %llu, expected %llu\n", seq, con->in_seq + 1);
+               con->error_msg = "bad message sequence # for incoming message";
+               return -EBADE;
+       }
+       ceph_con_discard_sent(con, le64_to_cpu(hdr2->ack_seq));
+       fill_header(&hdr, hdr2, desc->fd_lens[1], desc->fd_lens[2],
+                   desc->fd_lens[3], &con->peer_name);
+       ret = ceph_con_in_msg_alloc(con, &hdr, &skip);
+       if (ret)
+               return ret;
+       WARN_ON(!con->in_msg ^ skip);
+       if (skip)
+               return 0;
+       WARN_ON(!con->in_msg);
+       WARN_ON(con->in_msg->con != con);
+       return 1;
+ }
+ static int process_message(struct ceph_connection *con)
+ {
+       ceph_con_process_message(con);
+       /*
+        * We could have been closed by ceph_con_close() because
+        * ceph_con_process_message() temporarily drops con->mutex.
+        */
+       if (con->state != CEPH_CON_S_OPEN) {
+               dout("%s con %p state changed to %d\n", __func__, con,
+                    con->state);
+               return -EAGAIN;
+       }
+       prepare_read_preamble(con);
+       return 0;
+ }
+ static int __handle_control(struct ceph_connection *con, void *p)
+ {
+       void *end = p + con->v2.in_desc.fd_lens[0];
+       struct ceph_msg *msg;
+       int ret;
+       if (con->v2.in_desc.fd_tag != FRAME_TAG_MESSAGE)
+               return process_control(con, p, end);
+       ret = process_message_header(con, p, end);
+       if (ret < 0)
+               return ret;
+       if (ret == 0) {
+               prepare_skip_message(con);
+               return 0;
+       }
+       msg = con->in_msg;  /* set in process_message_header() */
+       if (!front_len(msg) && !middle_len(msg)) {
+               if (!data_len(msg))
+                       return process_message(con);
+               prepare_read_data(con);
+               return 0;
+       }
+       reset_in_kvecs(con);
+       if (front_len(msg)) {
+               WARN_ON(front_len(msg) > msg->front_alloc_len);
+               add_in_kvec(con, msg->front.iov_base, front_len(msg));
+               msg->front.iov_len = front_len(msg);
+               if (con_secure(con) && need_padding(front_len(msg)))
+                       add_in_kvec(con, FRONT_PAD(con->v2.in_buf),
+                                   padding_len(front_len(msg)));
+       } else {
+               msg->front.iov_len = 0;
+       }
+       if (middle_len(msg)) {
+               WARN_ON(middle_len(msg) > msg->middle->alloc_len);
+               add_in_kvec(con, msg->middle->vec.iov_base, middle_len(msg));
+               msg->middle->vec.iov_len = middle_len(msg);
+               if (con_secure(con) && need_padding(middle_len(msg)))
+                       add_in_kvec(con, MIDDLE_PAD(con->v2.in_buf),
+                                   padding_len(middle_len(msg)));
+       } else if (msg->middle) {
+               msg->middle->vec.iov_len = 0;
+       }
+       if (data_len(msg)) {
+               con->v2.in_state = IN_S_PREPARE_READ_DATA;
+       } else {
+               add_in_kvec(con, con->v2.in_buf,
+                           con_secure(con) ? CEPH_EPILOGUE_SECURE_LEN :
+                                             CEPH_EPILOGUE_PLAIN_LEN);
+               con->v2.in_state = IN_S_HANDLE_EPILOGUE;
+       }
+       return 0;
+ }
+ static int handle_preamble(struct ceph_connection *con)
+ {
+       struct ceph_frame_desc *desc = &con->v2.in_desc;
+       int ret;
+       if (con_secure(con)) {
+               ret = decrypt_preamble(con);
+               if (ret) {
+                       if (ret == -EBADMSG)
+                               con->error_msg = "integrity error, bad preamble auth tag";
+                       return ret;
+               }
+       }
+       ret = decode_preamble(con->v2.in_buf, desc);
+       if (ret) {
+               if (ret == -EBADMSG)
+                       con->error_msg = "integrity error, bad crc";
+               else
+                       con->error_msg = "protocol error, bad preamble";
+               return ret;
+       }
+       dout("%s con %p tag %d seg_cnt %d %d+%d+%d+%d\n", __func__,
+            con, desc->fd_tag, desc->fd_seg_cnt, desc->fd_lens[0],
+            desc->fd_lens[1], desc->fd_lens[2], desc->fd_lens[3]);
+       if (!con_secure(con))
+               return prepare_read_control(con);
+       if (desc->fd_lens[0] > CEPH_PREAMBLE_INLINE_LEN)
+               return prepare_read_control_remainder(con);
+       return __handle_control(con, CTRL_BODY(con->v2.in_buf));
+ }
+ static int handle_control(struct ceph_connection *con)
+ {
+       int ctrl_len = con->v2.in_desc.fd_lens[0];
+       void *buf;
+       int ret;
+       WARN_ON(con_secure(con));
+       ret = verify_control_crc(con);
+       if (ret) {
+               con->error_msg = "integrity error, bad crc";
+               return ret;
+       }
+       if (con->state == CEPH_CON_S_V2_AUTH) {
+               buf = alloc_conn_buf(con, ctrl_len);
+               if (!buf)
+                       return -ENOMEM;
+               memcpy(buf, con->v2.in_kvecs[0].iov_base, ctrl_len);
+               return __handle_control(con, buf);
+       }
+       return __handle_control(con, con->v2.in_kvecs[0].iov_base);
+ }
+ static int handle_control_remainder(struct ceph_connection *con)
+ {
+       int ret;
+       WARN_ON(!con_secure(con));
+       ret = decrypt_control_remainder(con);
+       if (ret) {
+               if (ret == -EBADMSG)
+                       con->error_msg = "integrity error, bad control remainder auth tag";
+               return ret;
+       }
+       return __handle_control(con, con->v2.in_kvecs[0].iov_base -
+                                    CEPH_PREAMBLE_INLINE_LEN);
+ }
+ static int handle_epilogue(struct ceph_connection *con)
+ {
+       u32 front_crc, middle_crc, data_crc;
+       int ret;
+       if (con_secure(con)) {
+               ret = decrypt_message(con);
+               if (ret) {
+                       if (ret == -EBADMSG)
+                               con->error_msg = "integrity error, bad epilogue auth tag";
+                       return ret;
+               }
+               /* just late_status */
+               ret = decode_epilogue(con->v2.in_buf, NULL, NULL, NULL);
+               if (ret) {
+                       con->error_msg = "protocol error, bad epilogue";
+                       return ret;
+               }
+       } else {
+               ret = decode_epilogue(con->v2.in_buf, &front_crc,
+                                     &middle_crc, &data_crc);
+               if (ret) {
+                       con->error_msg = "protocol error, bad epilogue";
+                       return ret;
+               }
+               ret = verify_epilogue_crcs(con, front_crc, middle_crc,
+                                          data_crc);
+               if (ret) {
+                       con->error_msg = "integrity error, bad crc";
+                       return ret;
+               }
+       }
+       return process_message(con);
+ }
+ static void finish_skip(struct ceph_connection *con)
+ {
+       dout("%s con %p\n", __func__, con);
+       if (con_secure(con))
+               gcm_inc_nonce(&con->v2.in_gcm_nonce);
+       __finish_skip(con);
+ }
+ static int populate_in_iter(struct ceph_connection *con)
+ {
+       int ret;
+       dout("%s con %p state %d in_state %d\n", __func__, con, con->state,
+            con->v2.in_state);
+       WARN_ON(iov_iter_count(&con->v2.in_iter));
+       if (con->state == CEPH_CON_S_V2_BANNER_PREFIX) {
+               ret = process_banner_prefix(con);
+       } else if (con->state == CEPH_CON_S_V2_BANNER_PAYLOAD) {
+               ret = process_banner_payload(con);
+       } else if ((con->state >= CEPH_CON_S_V2_HELLO &&
+                   con->state <= CEPH_CON_S_V2_SESSION_RECONNECT) ||
+                  con->state == CEPH_CON_S_OPEN) {
+               switch (con->v2.in_state) {
+               case IN_S_HANDLE_PREAMBLE:
+                       ret = handle_preamble(con);
+                       break;
+               case IN_S_HANDLE_CONTROL:
+                       ret = handle_control(con);
+                       break;
+               case IN_S_HANDLE_CONTROL_REMAINDER:
+                       ret = handle_control_remainder(con);
+                       break;
+               case IN_S_PREPARE_READ_DATA:
+                       prepare_read_data(con);
+                       ret = 0;
+                       break;
+               case IN_S_PREPARE_READ_DATA_CONT:
+                       prepare_read_data_cont(con);
+                       ret = 0;
+                       break;
+               case IN_S_HANDLE_EPILOGUE:
+                       ret = handle_epilogue(con);
+                       break;
+               case IN_S_FINISH_SKIP:
+                       finish_skip(con);
+                       ret = 0;
+                       break;
+               default:
+                       WARN(1, "bad in_state %d", con->v2.in_state);
+                       return -EINVAL;
+               }
+       } else {
+               WARN(1, "bad state %d", con->state);
+               return -EINVAL;
+       }
+       if (ret) {
+               dout("%s con %p error %d\n", __func__, con, ret);
+               return ret;
+       }
+       if (WARN_ON(!iov_iter_count(&con->v2.in_iter)))
+               return -ENODATA;
+       dout("%s con %p populated %zu\n", __func__, con,
+            iov_iter_count(&con->v2.in_iter));
+       return 1;
+ }
+ int ceph_con_v2_try_read(struct ceph_connection *con)
+ {
+       int ret;
+       dout("%s con %p state %d need %zu\n", __func__, con, con->state,
+            iov_iter_count(&con->v2.in_iter));
+       if (con->state == CEPH_CON_S_PREOPEN)
+               return 0;
+       /*
+        * We should always have something pending here.  If not,
+        * avoid calling populate_in_iter() as if we read something
+        * (ceph_tcp_recv() would immediately return 1).
+        */
+       if (WARN_ON(!iov_iter_count(&con->v2.in_iter)))
+               return -ENODATA;
+       for (;;) {
+               ret = ceph_tcp_recv(con);
+               if (ret <= 0)
+                       return ret;
+               ret = populate_in_iter(con);
+               if (ret <= 0) {
+                       if (ret && ret != -EAGAIN && !con->error_msg)
+                               con->error_msg = "read processing error";
+                       return ret;
+               }
+       }
+ }
+ static void queue_data(struct ceph_connection *con)
+ {
+       struct bio_vec bv;
+       con->v2.out_epil.data_crc = -1;
+       ceph_msg_data_cursor_init(&con->v2.out_cursor, con->out_msg,
+                                 data_len(con->out_msg));
+       get_bvec_at(&con->v2.out_cursor, &bv);
+       set_out_bvec(con, &bv, true);
+       con->v2.out_state = OUT_S_QUEUE_DATA_CONT;
+ }
+ static void queue_data_cont(struct ceph_connection *con)
+ {
+       struct bio_vec bv;
+       con->v2.out_epil.data_crc = ceph_crc32c_page(
+               con->v2.out_epil.data_crc, con->v2.out_bvec.bv_page,
+               con->v2.out_bvec.bv_offset, con->v2.out_bvec.bv_len);
+       ceph_msg_data_advance(&con->v2.out_cursor, con->v2.out_bvec.bv_len);
+       if (con->v2.out_cursor.total_resid) {
+               get_bvec_at(&con->v2.out_cursor, &bv);
+               set_out_bvec(con, &bv, true);
+               WARN_ON(con->v2.out_state != OUT_S_QUEUE_DATA_CONT);
+               return;
+       }
+       /*
+        * We've written all data.  Queue epilogue.  Once it's written,
+        * we are done.
+        */
+       reset_out_kvecs(con);
+       prepare_epilogue_plain(con, false);
+       con->v2.out_state = OUT_S_FINISH_MESSAGE;
+ }
+ static void queue_enc_page(struct ceph_connection *con)
+ {
+       struct bio_vec bv;
+       dout("%s con %p i %d resid %d\n", __func__, con, con->v2.out_enc_i,
+            con->v2.out_enc_resid);
+       WARN_ON(!con->v2.out_enc_resid);
+       bv.bv_page = con->v2.out_enc_pages[con->v2.out_enc_i];
+       bv.bv_offset = 0;
+       bv.bv_len = min(con->v2.out_enc_resid, (int)PAGE_SIZE);
+       set_out_bvec(con, &bv, false);
+       con->v2.out_enc_i++;
+       con->v2.out_enc_resid -= bv.bv_len;
+       if (con->v2.out_enc_resid) {
+               WARN_ON(con->v2.out_state != OUT_S_QUEUE_ENC_PAGE);
+               return;
+       }
+       /*
+        * We've queued the last piece of ciphertext (ending with
+        * epilogue) + auth tag.  Once it's written, we are done.
+        */
+       WARN_ON(con->v2.out_enc_i != con->v2.out_enc_page_cnt);
+       con->v2.out_state = OUT_S_FINISH_MESSAGE;
+ }
+ static void queue_zeros(struct ceph_connection *con)
+ {
+       dout("%s con %p out_zero %d\n", __func__, con, con->v2.out_zero);
+       if (con->v2.out_zero) {
+               set_out_bvec_zero(con);
+               con->v2.out_zero -= con->v2.out_bvec.bv_len;
+               con->v2.out_state = OUT_S_QUEUE_ZEROS;
+               return;
+       }
+       /*
+        * We've zero-filled everything up to epilogue.  Queue epilogue
+        * with late_status set to ABORTED and crcs adjusted for zeros.
+        * Once it's written, we are done patching up for the revoke.
+        */
+       reset_out_kvecs(con);
+       prepare_epilogue_plain(con, true);
+       con->v2.out_state = OUT_S_FINISH_MESSAGE;
+ }
+ static void finish_message(struct ceph_connection *con)
+ {
+       dout("%s con %p msg %p\n", __func__, con, con->out_msg);
+       /* we end up here both plain and secure modes */
+       if (con->v2.out_enc_pages) {
+               WARN_ON(!con->v2.out_enc_page_cnt);
+               ceph_release_page_vector(con->v2.out_enc_pages,
+                                        con->v2.out_enc_page_cnt);
+               con->v2.out_enc_pages = NULL;
+               con->v2.out_enc_page_cnt = 0;
+       }
+       /* message may have been revoked */
+       if (con->out_msg) {
+               ceph_msg_put(con->out_msg);
+               con->out_msg = NULL;
+       }
+       con->v2.out_state = OUT_S_GET_NEXT;
+ }
+ static int populate_out_iter(struct ceph_connection *con)
+ {
+       int ret;
+       dout("%s con %p state %d out_state %d\n", __func__, con, con->state,
+            con->v2.out_state);
+       WARN_ON(iov_iter_count(&con->v2.out_iter));
+       if (con->state != CEPH_CON_S_OPEN) {
+               WARN_ON(con->state < CEPH_CON_S_V2_BANNER_PREFIX ||
+                       con->state > CEPH_CON_S_V2_SESSION_RECONNECT);
+               goto nothing_pending;
+       }
+       switch (con->v2.out_state) {
+       case OUT_S_QUEUE_DATA:
+               WARN_ON(!con->out_msg);
+               queue_data(con);
+               goto populated;
+       case OUT_S_QUEUE_DATA_CONT:
+               WARN_ON(!con->out_msg);
+               queue_data_cont(con);
+               goto populated;
+       case OUT_S_QUEUE_ENC_PAGE:
+               queue_enc_page(con);
+               goto populated;
+       case OUT_S_QUEUE_ZEROS:
+               WARN_ON(con->out_msg);  /* revoked */
+               queue_zeros(con);
+               goto populated;
+       case OUT_S_FINISH_MESSAGE:
+               finish_message(con);
+               break;
+       case OUT_S_GET_NEXT:
+               break;
+       default:
+               WARN(1, "bad out_state %d", con->v2.out_state);
+               return -EINVAL;
+       }
+       WARN_ON(con->v2.out_state != OUT_S_GET_NEXT);
+       if (ceph_con_flag_test_and_clear(con, CEPH_CON_F_KEEPALIVE_PENDING)) {
+               ret = prepare_keepalive2(con);
+               if (ret) {
+                       pr_err("prepare_keepalive2 failed: %d\n", ret);
+                       return ret;
+               }
+       } else if (!list_empty(&con->out_queue)) {
+               ceph_con_get_out_msg(con);
+               ret = prepare_message(con);
+               if (ret) {
+                       pr_err("prepare_message failed: %d\n", ret);
+                       return ret;
+               }
+       } else if (con->in_seq > con->in_seq_acked) {
+               ret = prepare_ack(con);
+               if (ret) {
+                       pr_err("prepare_ack failed: %d\n", ret);
+                       return ret;
+               }
+       } else {
+               goto nothing_pending;
+       }
+ populated:
+       if (WARN_ON(!iov_iter_count(&con->v2.out_iter)))
+               return -ENODATA;
+       dout("%s con %p populated %zu\n", __func__, con,
+            iov_iter_count(&con->v2.out_iter));
+       return 1;
+ nothing_pending:
+       WARN_ON(iov_iter_count(&con->v2.out_iter));
+       dout("%s con %p nothing pending\n", __func__, con);
+       ceph_con_flag_clear(con, CEPH_CON_F_WRITE_PENDING);
+       return 0;
+ }
+ int ceph_con_v2_try_write(struct ceph_connection *con)
+ {
+       int ret;
+       dout("%s con %p state %d have %zu\n", __func__, con, con->state,
+            iov_iter_count(&con->v2.out_iter));
+       /* open the socket first? */
+       if (con->state == CEPH_CON_S_PREOPEN) {
+               WARN_ON(con->peer_addr.type != CEPH_ENTITY_ADDR_TYPE_MSGR2);
+               /*
+                * Always bump global_seq.  Bump connect_seq only if
+                * there is a session (i.e. we are reconnecting and will
+                * send session_reconnect instead of client_ident).
+                */
+               con->v2.global_seq = ceph_get_global_seq(con->msgr, 0);
+               if (con->v2.server_cookie)
+                       con->v2.connect_seq++;
+               ret = prepare_read_banner_prefix(con);
+               if (ret) {
+                       pr_err("prepare_read_banner_prefix failed: %d\n", ret);
+                       con->error_msg = "connect error";
+                       return ret;
+               }
+               reset_out_kvecs(con);
+               ret = prepare_banner(con);
+               if (ret) {
+                       pr_err("prepare_banner failed: %d\n", ret);
+                       con->error_msg = "connect error";
+                       return ret;
+               }
+               ret = ceph_tcp_connect(con);
+               if (ret) {
+                       pr_err("ceph_tcp_connect failed: %d\n", ret);
+                       con->error_msg = "connect error";
+                       return ret;
+               }
+       }
+       if (!iov_iter_count(&con->v2.out_iter)) {
+               ret = populate_out_iter(con);
+               if (ret <= 0) {
+                       if (ret && ret != -EAGAIN && !con->error_msg)
+                               con->error_msg = "write processing error";
+                       return ret;
+               }
+       }
+       tcp_sock_set_cork(con->sock->sk, true);
+       for (;;) {
+               ret = ceph_tcp_send(con);
+               if (ret <= 0)
+                       break;
+               ret = populate_out_iter(con);
+               if (ret <= 0) {
+                       if (ret && ret != -EAGAIN && !con->error_msg)
+                               con->error_msg = "write processing error";
+                       break;
+               }
+       }
+       tcp_sock_set_cork(con->sock->sk, false);
+       return ret;
+ }
+ static u32 crc32c_zeros(u32 crc, int zero_len)
+ {
+       int len;
+       while (zero_len) {
+               len = min(zero_len, (int)PAGE_SIZE);
+               crc = crc32c(crc, page_address(ceph_zero_page), len);
+               zero_len -= len;
+       }
+       return crc;
+ }
+ static void prepare_zero_front(struct ceph_connection *con, int resid)
+ {
+       int sent;
+       WARN_ON(!resid || resid > front_len(con->out_msg));
+       sent = front_len(con->out_msg) - resid;
+       dout("%s con %p sent %d resid %d\n", __func__, con, sent, resid);
+       if (sent) {
+               con->v2.out_epil.front_crc =
+                       crc32c(-1, con->out_msg->front.iov_base, sent);
+               con->v2.out_epil.front_crc =
+                       crc32c_zeros(con->v2.out_epil.front_crc, resid);
+       } else {
+               con->v2.out_epil.front_crc = crc32c_zeros(-1, resid);
+       }
+       con->v2.out_iter.count -= resid;
+       out_zero_add(con, resid);
+ }
+ static void prepare_zero_middle(struct ceph_connection *con, int resid)
+ {
+       int sent;
+       WARN_ON(!resid || resid > middle_len(con->out_msg));
+       sent = middle_len(con->out_msg) - resid;
+       dout("%s con %p sent %d resid %d\n", __func__, con, sent, resid);
+       if (sent) {
+               con->v2.out_epil.middle_crc =
+                       crc32c(-1, con->out_msg->middle->vec.iov_base, sent);
+               con->v2.out_epil.middle_crc =
+                       crc32c_zeros(con->v2.out_epil.middle_crc, resid);
+       } else {
+               con->v2.out_epil.middle_crc = crc32c_zeros(-1, resid);
+       }
+       con->v2.out_iter.count -= resid;
+       out_zero_add(con, resid);
+ }
+ static void prepare_zero_data(struct ceph_connection *con)
+ {
+       dout("%s con %p\n", __func__, con);
+       con->v2.out_epil.data_crc = crc32c_zeros(-1, data_len(con->out_msg));
+       out_zero_add(con, data_len(con->out_msg));
+ }
+ static void revoke_at_queue_data(struct ceph_connection *con)
+ {
+       int boundary;
+       int resid;
+       WARN_ON(!data_len(con->out_msg));
+       WARN_ON(!iov_iter_is_kvec(&con->v2.out_iter));
+       resid = iov_iter_count(&con->v2.out_iter);
+       boundary = front_len(con->out_msg) + middle_len(con->out_msg);
+       if (resid > boundary) {
+               resid -= boundary;
+               WARN_ON(resid > MESSAGE_HEAD_PLAIN_LEN);
+               dout("%s con %p was sending head\n", __func__, con);
+               if (front_len(con->out_msg))
+                       prepare_zero_front(con, front_len(con->out_msg));
+               if (middle_len(con->out_msg))
+                       prepare_zero_middle(con, middle_len(con->out_msg));
+               prepare_zero_data(con);
+               WARN_ON(iov_iter_count(&con->v2.out_iter) != resid);
+               con->v2.out_state = OUT_S_QUEUE_ZEROS;
+               return;
+       }
+       boundary = middle_len(con->out_msg);
+       if (resid > boundary) {
+               resid -= boundary;
+               dout("%s con %p was sending front\n", __func__, con);
+               prepare_zero_front(con, resid);
+               if (middle_len(con->out_msg))
+                       prepare_zero_middle(con, middle_len(con->out_msg));
+               prepare_zero_data(con);
+               queue_zeros(con);
+               return;
+       }
+       WARN_ON(!resid);
+       dout("%s con %p was sending middle\n", __func__, con);
+       prepare_zero_middle(con, resid);
+       prepare_zero_data(con);
+       queue_zeros(con);
+ }
+ static void revoke_at_queue_data_cont(struct ceph_connection *con)
+ {
+       int sent, resid;  /* current piece of data */
+       WARN_ON(!data_len(con->out_msg));
+       WARN_ON(!iov_iter_is_bvec(&con->v2.out_iter));
+       resid = iov_iter_count(&con->v2.out_iter);
+       WARN_ON(!resid || resid > con->v2.out_bvec.bv_len);
+       sent = con->v2.out_bvec.bv_len - resid;
+       dout("%s con %p sent %d resid %d\n", __func__, con, sent, resid);
+       if (sent) {
+               con->v2.out_epil.data_crc = ceph_crc32c_page(
+                       con->v2.out_epil.data_crc, con->v2.out_bvec.bv_page,
+                       con->v2.out_bvec.bv_offset, sent);
+               ceph_msg_data_advance(&con->v2.out_cursor, sent);
+       }
+       WARN_ON(resid > con->v2.out_cursor.total_resid);
+       con->v2.out_epil.data_crc = crc32c_zeros(con->v2.out_epil.data_crc,
+                                               con->v2.out_cursor.total_resid);
+       con->v2.out_iter.count -= resid;
+       out_zero_add(con, con->v2.out_cursor.total_resid);
+       queue_zeros(con);
+ }
+ static void revoke_at_finish_message(struct ceph_connection *con)
+ {
+       int boundary;
+       int resid;
+       WARN_ON(!iov_iter_is_kvec(&con->v2.out_iter));
+       resid = iov_iter_count(&con->v2.out_iter);
+       if (!front_len(con->out_msg) && !middle_len(con->out_msg) &&
+           !data_len(con->out_msg)) {
+               WARN_ON(!resid || resid > MESSAGE_HEAD_PLAIN_LEN);
+               dout("%s con %p was sending head (empty message) - noop\n",
+                    __func__, con);
+               return;
+       }
+       boundary = front_len(con->out_msg) + middle_len(con->out_msg) +
+                  CEPH_EPILOGUE_PLAIN_LEN;
+       if (resid > boundary) {
+               resid -= boundary;
+               WARN_ON(resid > MESSAGE_HEAD_PLAIN_LEN);
+               dout("%s con %p was sending head\n", __func__, con);
+               if (front_len(con->out_msg))
+                       prepare_zero_front(con, front_len(con->out_msg));
+               if (middle_len(con->out_msg))
+                       prepare_zero_middle(con, middle_len(con->out_msg));
+               con->v2.out_iter.count -= CEPH_EPILOGUE_PLAIN_LEN;
+               WARN_ON(iov_iter_count(&con->v2.out_iter) != resid);
+               con->v2.out_state = OUT_S_QUEUE_ZEROS;
+               return;
+       }
+       boundary = middle_len(con->out_msg) + CEPH_EPILOGUE_PLAIN_LEN;
+       if (resid > boundary) {
+               resid -= boundary;
+               dout("%s con %p was sending front\n", __func__, con);
+               prepare_zero_front(con, resid);
+               if (middle_len(con->out_msg))
+                       prepare_zero_middle(con, middle_len(con->out_msg));
+               con->v2.out_iter.count -= CEPH_EPILOGUE_PLAIN_LEN;
+               queue_zeros(con);
+               return;
+       }
+       boundary = CEPH_EPILOGUE_PLAIN_LEN;
+       if (resid > boundary) {
+               resid -= boundary;
+               dout("%s con %p was sending middle\n", __func__, con);
+               prepare_zero_middle(con, resid);
+               con->v2.out_iter.count -= CEPH_EPILOGUE_PLAIN_LEN;
+               queue_zeros(con);
+               return;
+       }
+       WARN_ON(!resid);
+       dout("%s con %p was sending epilogue - noop\n", __func__, con);
+ }
+ void ceph_con_v2_revoke(struct ceph_connection *con)
+ {
+       WARN_ON(con->v2.out_zero);
+       if (con_secure(con)) {
+               WARN_ON(con->v2.out_state != OUT_S_QUEUE_ENC_PAGE &&
+                       con->v2.out_state != OUT_S_FINISH_MESSAGE);
+               dout("%s con %p secure - noop\n", __func__, con);
+               return;
+       }
+       switch (con->v2.out_state) {
+       case OUT_S_QUEUE_DATA:
+               revoke_at_queue_data(con);
+               break;
+       case OUT_S_QUEUE_DATA_CONT:
+               revoke_at_queue_data_cont(con);
+               break;
+       case OUT_S_FINISH_MESSAGE:
+               revoke_at_finish_message(con);
+               break;
+       default:
+               WARN(1, "bad out_state %d", con->v2.out_state);
+               break;
+       }
+ }
+ static void revoke_at_prepare_read_data(struct ceph_connection *con)
+ {
+       int remaining;  /* data + [data padding] + epilogue */
+       int resid;
+       WARN_ON(!data_len(con->in_msg));
+       WARN_ON(!iov_iter_is_kvec(&con->v2.in_iter));
+       resid = iov_iter_count(&con->v2.in_iter);
+       WARN_ON(!resid);
+       if (con_secure(con))
+               remaining = padded_len(data_len(con->in_msg)) +
+                           CEPH_EPILOGUE_SECURE_LEN;
+       else
+               remaining = data_len(con->in_msg) + CEPH_EPILOGUE_PLAIN_LEN;
+       dout("%s con %p resid %d remaining %d\n", __func__, con, resid,
+            remaining);
+       con->v2.in_iter.count -= resid;
+       set_in_skip(con, resid + remaining);
+       con->v2.in_state = IN_S_FINISH_SKIP;
+ }
+ static void revoke_at_prepare_read_data_cont(struct ceph_connection *con)
+ {
+       int recved, resid;  /* current piece of data */
+       int remaining;  /* [data padding] + epilogue */
+       WARN_ON(!data_len(con->in_msg));
+       WARN_ON(!iov_iter_is_bvec(&con->v2.in_iter));
+       resid = iov_iter_count(&con->v2.in_iter);
+       WARN_ON(!resid || resid > con->v2.in_bvec.bv_len);
+       recved = con->v2.in_bvec.bv_len - resid;
+       dout("%s con %p recved %d resid %d\n", __func__, con, recved, resid);
+       if (recved)
+               ceph_msg_data_advance(&con->v2.in_cursor, recved);
+       WARN_ON(resid > con->v2.in_cursor.total_resid);
+       if (con_secure(con))
+               remaining = padding_len(data_len(con->in_msg)) +
+                           CEPH_EPILOGUE_SECURE_LEN;
+       else
+               remaining = CEPH_EPILOGUE_PLAIN_LEN;
+       dout("%s con %p total_resid %zu remaining %d\n", __func__, con,
+            con->v2.in_cursor.total_resid, remaining);
+       con->v2.in_iter.count -= resid;
+       set_in_skip(con, con->v2.in_cursor.total_resid + remaining);
+       con->v2.in_state = IN_S_FINISH_SKIP;
+ }
+ static void revoke_at_handle_epilogue(struct ceph_connection *con)
+ {
+       int resid;
+       WARN_ON(!iov_iter_is_kvec(&con->v2.in_iter));
+       resid = iov_iter_count(&con->v2.in_iter);
+       WARN_ON(!resid);
+       dout("%s con %p resid %d\n", __func__, con, resid);
+       con->v2.in_iter.count -= resid;
+       set_in_skip(con, resid);
+       con->v2.in_state = IN_S_FINISH_SKIP;
+ }
+ void ceph_con_v2_revoke_incoming(struct ceph_connection *con)
+ {
+       switch (con->v2.in_state) {
+       case IN_S_PREPARE_READ_DATA:
+               revoke_at_prepare_read_data(con);
+               break;
+       case IN_S_PREPARE_READ_DATA_CONT:
+               revoke_at_prepare_read_data_cont(con);
+               break;
+       case IN_S_HANDLE_EPILOGUE:
+               revoke_at_handle_epilogue(con);
+               break;
+       default:
+               WARN(1, "bad in_state %d", con->v2.in_state);
+               break;
+       }
+ }
+ bool ceph_con_v2_opened(struct ceph_connection *con)
+ {
+       return con->v2.peer_global_seq;
+ }
+ void ceph_con_v2_reset_session(struct ceph_connection *con)
+ {
+       con->v2.client_cookie = 0;
+       con->v2.server_cookie = 0;
+       con->v2.global_seq = 0;
+       con->v2.connect_seq = 0;
+       con->v2.peer_global_seq = 0;
+ }
+ void ceph_con_v2_reset_protocol(struct ceph_connection *con)
+ {
+       iov_iter_truncate(&con->v2.in_iter, 0);
+       iov_iter_truncate(&con->v2.out_iter, 0);
+       con->v2.out_zero = 0;
+       clear_in_sign_kvecs(con);
+       clear_out_sign_kvecs(con);
+       free_conn_bufs(con);
+       if (con->v2.out_enc_pages) {
+               WARN_ON(!con->v2.out_enc_page_cnt);
+               ceph_release_page_vector(con->v2.out_enc_pages,
+                                        con->v2.out_enc_page_cnt);
+               con->v2.out_enc_pages = NULL;
+               con->v2.out_enc_page_cnt = 0;
+       }
+       con->v2.con_mode = CEPH_CON_MODE_UNKNOWN;
+       if (con->v2.hmac_tfm) {
+               crypto_free_shash(con->v2.hmac_tfm);
+               con->v2.hmac_tfm = NULL;
+       }
+       if (con->v2.gcm_req) {
+               aead_request_free(con->v2.gcm_req);
+               con->v2.gcm_req = NULL;
+       }
+       if (con->v2.gcm_tfm) {
+               crypto_free_aead(con->v2.gcm_tfm);
+               con->v2.gcm_tfm = NULL;
+       }
+ }