Provide an iterator-like interface as initializer lists cannot be
formed dynamically.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit 1fc5cc2)

Add asserts to avoid bugs like the one fixed in 1a975fb
("msg/async: fix unnecessary 4 kB allocation in secure mode.").

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit 4894e59)

It is unused and doesn't make much sense in TxHandler.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit b3e39b1)

OpenSSL supports in-place decryption so we can avoid
allocating potentially multi-megabyte and strictly aligned
buffer for each decryption operation.

ProtocolV2 actually gets the alignment wrong: after
read_frame_segment() allocates with cur_rx_desc.alignment,
handle_read_frame_segment() effectively replaces that with
segment_t::DEFAULT_ALIGNMENT.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit fe97a00)

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit e1d1f61)

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit 6b6d405)

Use it in ProtocolV2.h and later in unit tests.

While at it, drop the unused len struct.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit c081f3c)

Conflicts:
	src/crimson/net/ProtocolV2.cc [ crimson doesn't support
	  msgr2 in nautilus ]
	src/crimson/net/ProtocolV2.h [ ditto ]

Start separating frame assembly and disassembly code from
frame sending, receiving and handling code, so that assembly
and disassembly pieces can be unit tested and hopefully also
shared between different messengers (e.g. crimson).

This commit factors out the assembly code from Frame.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit 872b125)

Conflicts:
	src/crimson/CMakeLists.txt [ crimson doesn't support msgr2
	  in nautilus
	src/crimson/net/ProtocolV2.cc [ ditto ]
	src/crimson/net/ProtocolV2.h [ ditto ]
	src/msg/async/frames_v2.h [ commits f1cf408
	  ("msg/async/frames_v2.h: fix warning"), c70f779
	  ("headers: Make ceph_le member private"), 9908f0e
	  ("msg: Add optimizing move") and 1a975fb ("msg/async:
	  fix unnecessary 4 kB allocation in secure mode.") not in
	  nautilus; fmt include adjusted as in rgw_lc.cc ]

Factor out the disassembly code from ProtocolV2 and switch
ProtocolV2 to FrameAssembler.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit b9e0cfe)

Conflicts:
	src/msg/async/ProtocolV2.cc [ context: commit d3ec4c01d17
	  ("msg: Build target 'common' without using namespace in
	  headers") not in nautilus ]

l_msgr_recv_bytes calculation was never updated from msgr1.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit dcf30f5)

In preparation for msgr2,1, rename epilogue structs:
epilogue_plain_block_t to epilogue_crc_rev0_block_t and
epilogue_secure_block_t to epilogue_secure_rev0_block_t
(rev0 stands for revision 0).

Also, get rid of size constants that just disguise the
struct type.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit 712915b)

Conflicts:
	src/crimson/net/ProtocolV2.cc [ crimson doesn't support
	  msgr2 in nautilus ]

Clarify that the frame can be aborted at any point after the
preamble and the first segment are put on the wire.  When that
happens, the remaining segments (including the data segment)
may be filled with zeros.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit bc835b8)

Conflicts:
	src/crimson/net/ProtocolV2.cc [ crimson doesn't support
	  msgr2 in nautilus ]
	src/msg/async/frames_v2.h [ context: commit c70f779
	  ("headers: Make ceph_le member private") not in nautilus ]

Implement msgr2.1-crc and msgr2.1-secure modes.

Issues with existing msgr2.0-crc and msgr2.0-secure modes and
their resolution will be described in doc/dev/msgr2.rst.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit 2966b2a)

Conflicts:
	src/crimson/net/ProtocolV2.cc [ crimson doesn't support
	  msgr2 in nautilus ]

reuse_connection() can be called on exproto in BANNER_CONNECTING
(i.e. without peer_supported_features and with tx/rx_frame_asm set to
msgr2.0), but this state isn't carried over.  If the donor connection
is msgr2.1, this leads to repeated connection faults on crc or auth tag
mismatches because we end up assembling 2.0 frames while the peer is
expecting 2.1 frames.

Fixes: https://tracker.ceph.com/issues/46180
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit baff20a)

Conflicts:
	src/test/msgr/test_msgr.cc [ commits 5e3aa5d
	  ("ceph_test_msgr: remove simple") and bfb8c74
	  ("test/msgr: s/Mutex/ceph::mutex/") not in nautilus ]