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* [PATCH 00/44] SHA-256 part 2/3: protocol functionality
@ 2020-05-13  0:53 brian m. carlson
  2020-05-13  0:53 ` [PATCH 01/44] t1050: match object ID paths in a hash-insensitive way brian m. carlson
                   ` (45 more replies)
  0 siblings, 46 replies; 175+ messages in thread
From: brian m. carlson @ 2020-05-13  0:53 UTC (permalink / raw)
  To: git; +Cc: Jonathan Tan

This is part 2 of 3 of the SHA-256 work.  This series, which is
unfortunately longer than I'd like, adds all of the protocol logic to
work with SHA-256 repositories.

It was originally planned that we would not upgrade the protocol and
would use SHA-1 for all protocol functionality until some point in the
future.  However, doing that requires a huge amount of additional work
(probably incorporating several hundred more patches which are not yet
written) and it's not possible to get the test suite to even come close
to passing without a way to fetch and push repositories.  I therefore
decided that implementing an object-format extension was the best way
forward.

This series provides object-format extensions for both the original and
v2 protocols, including full documentation.  Helpers, such as
git-remote-https, also learn capabilities to pass the object-format
extension back and forth, and to query its state.  The code is designed
to allow multiple object-format extensions to be provided if the server
supports multiple algorithms for one repo and to default to SHA-1 if no
object-format extension is provided.

The other two cases are the dumb HTTP protocol and bundles, both of
which have no object-format extension (because they provide no
capabilities) and are therefore distinguished solely by their hash
length.  We will have problems if in the future we need to use another
256-bit algorithm, but I plan to be improvident and hope that we'll move
to longer algorithms in the future to cover ourselves for post-quantum
security.

Clone support is necessarily a little tricky because we are initializing
a repository and then fetching refs, at which point we learn what hash
algorithm the remote side supports.  We work around this by calling the
code that updates the hash algorithm and repository version a second
time to rewrite that data once we know what version we're using.  This
is the most robust way I could approach this problem, but it is still a
little ugly.

As mentioned, this series is longer than I'd like, but it is complete:
this is all the SHA-256 protocol work.  Additional future series include
one last series of test fixes (28 patches) plus six final patches in the
series that enables SHA-256 support.

brian m. carlson (44):
  t1050: match object ID paths in a hash-insensitive way
  Documentation: document v1 protocol object-format capability
  connect: have ref processing code take struct packet_reader
  wrapper: add function to compare strings with different NUL
    termination
  remote: advertise the object-format capability on the server side
  connect: add function to parse multiple v1 capability values
  connect: add function to fetch value of a v2 server capability
  pkt-line: add a member for hash algorithm
  transport: add a hash algorithm member
  connect: add function to detect supported v1 hash functions
  send-pack: detect when the server doesn't support our hash
  connect: make parse_feature_value extern
  fetch-pack: detect when the server doesn't support our hash
  connect: detect algorithm when fetching refs
  builtin/receive-pack: detect when the server doesn't support our hash
  docs: update remote helper docs for object-format extensions
  transport-helper: implement object-format extensions
  remote-curl: implement object-format extensions
  builtin/clone: initialize hash algorithm properly
  t5562: pass object-format in synthesized test data
  t5704: send object-format capability with SHA-256
  fetch-pack: parse and advertise the object-format capability
  setup: set the_repository's hash algo when checking format
  t3200: mark assertion with SHA1 prerequisite
  packfile: compute and use the index CRC offset
  t5302: modernize test formatting
  builtin/show-index: provide options to determine hash algo
  t1302: expect repo format version 1 for SHA-256
  Documentation/technical: document object-format for protocol v2
  connect: pass full packet reader when parsing v2 refs
  connect: parse v2 refs with correct hash algorithm
  serve: advertise object-format capability for protocol v2
  t5500: make hash independent
  builtin/ls-remote: initialize repository based on fetch
  remote-curl: detect algorithm for dumb HTTP by size
  builtin/index-pack: add option to specify hash algorithm
  t1050: pass algorithm to index-pack when outside repo
  remote-curl: avoid truncating refs with ls-remote
  t/helper: initialize the repository for test-sha1-array
  t5702: offer an object-format capability in the test
  t5703: use object-format serve option
  t5300: pass --object-format to git index-pack
  bundle: detect hash algorithm when reading refs
  remote-testgit: adapt for object-format

 Documentation/gitremote-helpers.txt           |  33 +-
 .../technical/protocol-capabilities.txt       |  16 +-
 Documentation/technical/protocol-v2.txt       |   9 +
 builtin/clone.c                               |   9 +
 builtin/index-pack.c                          |  11 +-
 builtin/ls-remote.c                           |   4 +
 builtin/receive-pack.c                        |  10 +
 builtin/show-index.c                          |  29 +-
 bundle.c                                      |  22 +-
 bundle.h                                      |   1 +
 connect.c                                     | 136 +++++--
 connect.h                                     |   3 +
 fetch-pack.c                                  |  14 +
 git-compat-util.h                             |   2 +
 git.c                                         |   2 +-
 object-store.h                                |   1 +
 packfile.c                                    |   1 +
 pkt-line.c                                    |   1 +
 pkt-line.h                                    |   3 +
 remote-curl.c                                 |  46 ++-
 send-pack.c                                   |   6 +
 serve.c                                       |  27 ++
 setup.c                                       |   1 +
 t/helper/test-oid-array.c                     |   3 +
 t/t1050-large.sh                              |   6 +-
 t/t1302-repo-version.sh                       |   6 +-
 t/t3200-branch.sh                             |   2 +-
 t/t5300-pack-object.sh                        |   9 +-
 t/t5302-pack-index.sh                         | 360 +++++++++---------
 t/t5500-fetch-pack.sh                         |   5 +-
 t/t5562-http-backend-content-length.sh        |  14 +-
 t/t5701-git-serve.sh                          |  28 +-
 t/t5702-protocol-v2.sh                        |   2 +
 t/t5703-upload-pack-ref-in-want.sh            |  19 +-
 t/t5704-protocol-violations.sh                |  12 +
 t/t5801/git-remote-testgit                    |   6 +
 t/test-lib.sh                                 |   1 +
 transport-helper.c                            |  24 +-
 transport.c                                   |  18 +-
 transport.h                                   |   8 +
 upload-pack.c                                 |   3 +-
 wrapper.c                                     |  12 +
 42 files changed, 670 insertions(+), 255 deletions(-)


^ permalink raw reply	[flat|nested] 175+ messages in thread

end of thread, other threads:[~2020-06-20  1:34 UTC | newest]

Thread overview: 175+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-05-13  0:53 [PATCH 00/44] SHA-256 part 2/3: protocol functionality brian m. carlson
2020-05-13  0:53 ` [PATCH 01/44] t1050: match object ID paths in a hash-insensitive way brian m. carlson
2020-05-13  0:53 ` [PATCH 02/44] Documentation: document v1 protocol object-format capability brian m. carlson
2020-05-13 19:28   ` Martin Ågren
2020-05-14  1:12     ` Junio C Hamano
2020-05-15 23:22       ` brian m. carlson
2020-05-16  0:02         ` Junio C Hamano
2020-05-13  0:53 ` [PATCH 03/44] connect: have ref processing code take struct packet_reader brian m. carlson
2020-05-13 19:30   ` Martin Ågren
2020-05-13  0:53 ` [PATCH 04/44] wrapper: add function to compare strings with different NUL termination brian m. carlson
2020-05-13 19:32   ` Martin Ågren
2020-05-13  0:53 ` [PATCH 05/44] remote: advertise the object-format capability on the server side brian m. carlson
2020-05-13  0:53 ` [PATCH 06/44] connect: add function to parse multiple v1 capability values brian m. carlson
2020-05-13  0:53 ` [PATCH 07/44] connect: add function to fetch value of a v2 server capability brian m. carlson
2020-05-13 19:37   ` Martin Ågren
2020-05-13  0:53 ` [PATCH 08/44] pkt-line: add a member for hash algorithm brian m. carlson
2020-05-13  0:53 ` [PATCH 09/44] transport: add a hash algorithm member brian m. carlson
2020-05-13  0:53 ` [PATCH 10/44] connect: add function to detect supported v1 hash functions brian m. carlson
2020-05-13 19:39   ` Martin Ågren
2020-05-13 22:49     ` brian m. carlson
2020-05-13  0:53 ` [PATCH 11/44] send-pack: detect when the server doesn't support our hash brian m. carlson
2020-05-13 19:41   ` Martin Ågren
2020-05-13 22:52     ` brian m. carlson
2020-05-13  0:53 ` [PATCH 12/44] connect: make parse_feature_value extern brian m. carlson
2020-05-13 19:48   ` Martin Ågren
2020-05-13  0:53 ` [PATCH 13/44] fetch-pack: detect when the server doesn't support our hash brian m. carlson
2020-05-13  0:53 ` [PATCH 14/44] connect: detect algorithm when fetching refs brian m. carlson
2020-05-16 10:40   ` Martin Ågren
2020-05-16 19:59     ` brian m. carlson
2020-05-13  0:53 ` [PATCH 15/44] builtin/receive-pack: detect when the server doesn't support our hash brian m. carlson
2020-05-16 10:41   ` Martin Ågren
2020-05-13  0:53 ` [PATCH 16/44] docs: update remote helper docs for object-format extensions brian m. carlson
2020-05-13  0:53 ` [PATCH 17/44] transport-helper: implement " brian m. carlson
2020-05-13  0:53 ` [PATCH 18/44] remote-curl: " brian m. carlson
2020-05-13  0:53 ` [PATCH 19/44] builtin/clone: initialize hash algorithm properly brian m. carlson
2020-05-16 10:48   ` Martin Ågren
2020-05-13  0:54 ` [PATCH 20/44] t5562: pass object-format in synthesized test data brian m. carlson
2020-05-16 10:55   ` Martin Ågren
2020-05-16 19:50     ` brian m. carlson
2020-05-13  0:54 ` [PATCH 21/44] t5704: send object-format capability with SHA-256 brian m. carlson
2020-05-16 11:02   ` Martin Ågren
2020-05-16 19:14     ` brian m. carlson
2020-05-13  0:54 ` [PATCH 22/44] fetch-pack: parse and advertise the object-format capability brian m. carlson
2020-05-16 11:03   ` Martin Ågren
2020-05-13  0:54 ` [PATCH 23/44] setup: set the_repository's hash algo when checking format brian m. carlson
2020-05-16 11:03   ` Martin Ågren
2020-05-16 19:29     ` brian m. carlson
2020-05-13  0:54 ` [PATCH 24/44] t3200: mark assertion with SHA1 prerequisite brian m. carlson
2020-05-16 11:04   ` Martin Ågren
2020-05-13  0:54 ` [PATCH 25/44] packfile: compute and use the index CRC offset brian m. carlson
2020-05-16 11:12   ` Martin Ågren
2020-05-13  0:54 ` [PATCH 26/44] t5302: modernize test formatting brian m. carlson
2020-05-13  0:54 ` [PATCH 27/44] builtin/show-index: provide options to determine hash algo brian m. carlson
2020-05-18 16:20   ` Junio C Hamano
2020-05-19  0:31     ` brian m. carlson
2020-05-13  0:54 ` [PATCH 28/44] t1302: expect repo format version 1 for SHA-256 brian m. carlson
2020-05-13  0:54 ` [PATCH 29/44] Documentation/technical: document object-format for protocol v2 brian m. carlson
2020-05-13  0:54 ` [PATCH 30/44] connect: pass full packet reader when parsing v2 refs brian m. carlson
2020-05-16 11:13   ` Martin Ågren
2020-05-13  0:54 ` [PATCH 31/44] connect: parse v2 refs with correct hash algorithm brian m. carlson
2020-05-16 11:14   ` Martin Ågren
2020-05-17 22:37     ` brian m. carlson
2020-05-13  0:54 ` [PATCH 32/44] serve: advertise object-format capability for protocol v2 brian m. carlson
2020-05-16 11:15   ` Martin Ågren
2020-05-13  0:54 ` [PATCH 33/44] t5500: make hash independent brian m. carlson
2020-05-13  0:54 ` [PATCH 34/44] builtin/ls-remote: initialize repository based on fetch brian m. carlson
2020-05-16 11:16   ` Martin Ågren
2020-05-16 20:28     ` brian m. carlson
2020-05-13  0:54 ` [PATCH 35/44] remote-curl: detect algorithm for dumb HTTP by size brian m. carlson
2020-05-16 11:17   ` Martin Ågren
2020-05-13  0:54 ` [PATCH 36/44] builtin/index-pack: add option to specify hash algorithm brian m. carlson
2020-05-16 11:18   ` Martin Ågren
2020-05-16 20:47     ` brian m. carlson
2020-05-17 18:16       ` Martin Ågren
2020-05-17 20:52         ` brian m. carlson
2020-05-13  0:54 ` [PATCH 37/44] t1050: pass algorithm to index-pack when outside repo brian m. carlson
2020-05-13  0:54 ` [PATCH 38/44] remote-curl: avoid truncating refs with ls-remote brian m. carlson
2020-05-13  0:54 ` [PATCH 39/44] t/helper: initialize the repository for test-sha1-array brian m. carlson
2020-05-13  0:54 ` [PATCH 40/44] t5702: offer an object-format capability in the test brian m. carlson
2020-05-13  0:54 ` [PATCH 41/44] t5703: use object-format serve option brian m. carlson
2020-05-13  0:54 ` [PATCH 42/44] t5300: pass --object-format to git index-pack brian m. carlson
2020-05-13  0:54 ` [PATCH 43/44] bundle: detect hash algorithm when reading refs brian m. carlson
2020-05-13  0:54 ` [PATCH 44/44] remote-testgit: adapt for object-format brian m. carlson
2020-05-25 19:58 ` [PATCH v2 00/44] SHA-256 part 2/3: protocol functionality brian m. carlson
2020-05-25 19:58   ` [PATCH v2 01/44] t1050: match object ID paths in a hash-insensitive way brian m. carlson
2020-05-25 19:58   ` [PATCH v2 02/44] Documentation: document v1 protocol object-format capability brian m. carlson
2020-05-25 19:58   ` [PATCH v2 03/44] connect: have ref processing code take struct packet_reader brian m. carlson
2020-05-25 19:58   ` [PATCH v2 04/44] wrapper: add function to compare strings with different NUL termination brian m. carlson
2020-05-25 19:58   ` [PATCH v2 05/44] remote: advertise the object-format capability on the server side brian m. carlson
2020-05-25 19:58   ` [PATCH v2 06/44] connect: add function to parse multiple v1 capability values brian m. carlson
2020-05-25 19:58   ` [PATCH v2 07/44] connect: add function to fetch value of a v2 server capability brian m. carlson
2020-05-25 19:58   ` [PATCH v2 08/44] pkt-line: add a member for hash algorithm brian m. carlson
2020-05-25 19:58   ` [PATCH v2 09/44] transport: add a hash algorithm member brian m. carlson
2020-05-25 19:58   ` [PATCH v2 10/44] connect: add function to detect supported v1 hash functions brian m. carlson
2020-05-25 19:58   ` [PATCH v2 11/44] send-pack: detect when the server doesn't support our hash brian m. carlson
2020-05-25 19:58   ` [PATCH v2 12/44] connect: make parse_feature_value extern brian m. carlson
2020-05-25 19:58   ` [PATCH v2 13/44] fetch-pack: detect when the server doesn't support our hash brian m. carlson
2020-05-25 19:59   ` [PATCH v2 14/44] connect: detect algorithm when fetching refs brian m. carlson
2020-05-25 19:59   ` [PATCH v2 15/44] builtin/receive-pack: detect when the server doesn't support our hash brian m. carlson
2020-05-25 19:59   ` [PATCH v2 16/44] docs: update remote helper docs for object-format extensions brian m. carlson
2020-05-25 19:59   ` [PATCH v2 17/44] transport-helper: implement " brian m. carlson
2020-05-25 19:59   ` [PATCH v2 18/44] remote-curl: " brian m. carlson
2020-05-25 19:59   ` [PATCH v2 19/44] builtin/clone: initialize hash algorithm properly brian m. carlson
2020-05-25 19:59   ` [PATCH v2 20/44] t5562: pass object-format in synthesized test data brian m. carlson
2020-05-25 19:59   ` [PATCH v2 21/44] fetch-pack: parse and advertise the object-format capability brian m. carlson
2020-05-25 19:59   ` [PATCH v2 22/44] setup: set the_repository's hash algo when checking format brian m. carlson
2020-05-25 19:59   ` [PATCH v2 23/44] t3200: mark assertion with SHA1 prerequisite brian m. carlson
2020-05-25 19:59   ` [PATCH v2 24/44] packfile: compute and use the index CRC offset brian m. carlson
2020-05-25 19:59   ` [PATCH v2 25/44] t5302: modernize test formatting brian m. carlson
2020-05-25 19:59   ` [PATCH v2 26/44] builtin/show-index: provide options to determine hash algo brian m. carlson
2020-05-25 19:59   ` [PATCH v2 27/44] t1302: expect repo format version 1 for SHA-256 brian m. carlson
2020-05-25 19:59   ` [PATCH v2 28/44] Documentation/technical: document object-format for protocol v2 brian m. carlson
2020-05-25 19:59   ` [PATCH v2 29/44] connect: pass full packet reader when parsing v2 refs brian m. carlson
2020-05-25 19:59   ` [PATCH v2 30/44] connect: parse v2 refs with correct hash algorithm brian m. carlson
2020-05-25 19:59   ` [PATCH v2 31/44] serve: advertise object-format capability for protocol v2 brian m. carlson
2020-05-25 19:59   ` [PATCH v2 32/44] t5500: make hash independent brian m. carlson
2020-05-25 19:59   ` [PATCH v2 33/44] builtin/ls-remote: initialize repository based on fetch brian m. carlson
2020-05-25 19:59   ` [PATCH v2 34/44] remote-curl: detect algorithm for dumb HTTP by size brian m. carlson
2020-05-25 19:59   ` [PATCH v2 35/44] builtin/index-pack: add option to specify hash algorithm brian m. carlson
2020-05-25 19:59   ` [PATCH v2 36/44] t1050: pass algorithm to index-pack when outside repo brian m. carlson
2020-05-25 19:59   ` [PATCH v2 37/44] remote-curl: avoid truncating refs with ls-remote brian m. carlson
2020-05-25 19:59   ` [PATCH v2 38/44] t/helper: initialize the repository for test-sha1-array brian m. carlson
2020-05-25 19:59   ` [PATCH v2 39/44] t5702: offer an object-format capability in the test brian m. carlson
2020-05-25 19:59   ` [PATCH v2 40/44] t5703: use object-format serve option brian m. carlson
2020-05-25 19:59   ` [PATCH v2 41/44] t5704: send object-format capability with SHA-256 brian m. carlson
2020-05-25 19:59   ` [PATCH v2 42/44] t5300: pass --object-format to git index-pack brian m. carlson
2020-05-25 19:59   ` [PATCH v2 43/44] bundle: detect hash algorithm when reading refs brian m. carlson
2020-05-25 19:59   ` [PATCH v2 44/44] remote-testgit: adapt for object-format brian m. carlson
2020-06-19 17:55 ` [PATCH v3 00/44] SHA-256 part 2/3: protocol functionality brian m. carlson
2020-06-19 17:55   ` [PATCH v3 01/44] t1050: match object ID paths in a hash-insensitive way brian m. carlson
2020-06-19 17:55   ` [PATCH v3 02/44] Documentation: document v1 protocol object-format capability brian m. carlson
2020-06-19 17:55   ` [PATCH v3 03/44] connect: have ref processing code take struct packet_reader brian m. carlson
2020-06-19 17:55   ` [PATCH v3 04/44] wrapper: add function to compare strings with different NUL termination brian m. carlson
2020-06-19 17:55   ` [PATCH v3 05/44] remote: advertise the object-format capability on the server side brian m. carlson
2020-06-19 17:55   ` [PATCH v3 06/44] connect: add function to parse multiple v1 capability values brian m. carlson
2020-06-19 17:55   ` [PATCH v3 07/44] connect: add function to fetch value of a v2 server capability brian m. carlson
2020-06-19 17:55   ` [PATCH v3 08/44] pkt-line: add a member for hash algorithm brian m. carlson
2020-06-19 17:55   ` [PATCH v3 09/44] transport: add a hash algorithm member brian m. carlson
2020-06-19 17:55   ` [PATCH v3 10/44] connect: add function to detect supported v1 hash functions brian m. carlson
2020-06-19 17:55   ` [PATCH v3 11/44] send-pack: detect when the server doesn't support our hash brian m. carlson
2020-06-19 17:55   ` [PATCH v3 12/44] connect: make parse_feature_value extern brian m. carlson
2020-06-19 17:55   ` [PATCH v3 13/44] fetch-pack: detect when the server doesn't support our hash brian m. carlson
2020-06-19 17:55   ` [PATCH v3 14/44] connect: detect algorithm when fetching refs brian m. carlson
2020-06-19 17:55   ` [PATCH v3 15/44] builtin/receive-pack: detect when the server doesn't support our hash brian m. carlson
2020-06-19 17:55   ` [PATCH v3 16/44] docs: update remote helper docs for object-format extensions brian m. carlson
2020-06-19 17:55   ` [PATCH v3 17/44] transport-helper: implement " brian m. carlson
2020-06-19 17:55   ` [PATCH v3 18/44] remote-curl: " brian m. carlson
2020-06-19 17:55   ` [PATCH v3 19/44] builtin/clone: initialize hash algorithm properly brian m. carlson
2020-06-19 17:55   ` [PATCH v3 20/44] t5562: pass object-format in synthesized test data brian m. carlson
2020-06-19 17:55   ` [PATCH v3 21/44] fetch-pack: parse and advertise the object-format capability brian m. carlson
2020-06-19 17:55   ` [PATCH v3 22/44] setup: set the_repository's hash algo when checking format brian m. carlson
2020-06-19 17:55   ` [PATCH v3 23/44] t3200: mark assertion with SHA1 prerequisite brian m. carlson
2020-06-19 17:55   ` [PATCH v3 24/44] packfile: compute and use the index CRC offset brian m. carlson
2020-06-19 17:55   ` [PATCH v3 25/44] t5302: modernize test formatting brian m. carlson
2020-06-19 17:55   ` [PATCH v3 26/44] builtin/show-index: provide options to determine hash algo brian m. carlson
2020-06-19 17:55   ` [PATCH v3 27/44] t1302: expect repo format version 1 for SHA-256 brian m. carlson
2020-06-19 17:55   ` [PATCH v3 28/44] Documentation/technical: document object-format for protocol v2 brian m. carlson
2020-06-19 17:55   ` [PATCH v3 29/44] connect: pass full packet reader when parsing v2 refs brian m. carlson
2020-06-19 17:55   ` [PATCH v3 30/44] connect: parse v2 refs with correct hash algorithm brian m. carlson
2020-06-19 17:55   ` [PATCH v3 31/44] serve: advertise object-format capability for protocol v2 brian m. carlson
2020-06-19 17:55   ` [PATCH v3 32/44] t5500: make hash independent brian m. carlson
2020-06-19 17:55   ` [PATCH v3 33/44] builtin/ls-remote: initialize repository based on fetch brian m. carlson
2020-06-19 17:55   ` [PATCH v3 34/44] remote-curl: detect algorithm for dumb HTTP by size brian m. carlson
2020-06-19 17:55   ` [PATCH v3 35/44] builtin/index-pack: add option to specify hash algorithm brian m. carlson
2020-06-19 17:55   ` [PATCH v3 36/44] t1050: pass algorithm to index-pack when outside repo brian m. carlson
2020-06-19 17:55   ` [PATCH v3 37/44] remote-curl: avoid truncating refs with ls-remote brian m. carlson
2020-06-19 17:55   ` [PATCH v3 38/44] t/helper: initialize the repository for test-sha1-array brian m. carlson
2020-06-19 17:55   ` [PATCH v3 39/44] t5702: offer an object-format capability in the test brian m. carlson
2020-06-19 17:55   ` [PATCH v3 40/44] t5703: use object-format serve option brian m. carlson
2020-06-19 17:55   ` [PATCH v3 41/44] t5704: send object-format capability with SHA-256 brian m. carlson
2020-06-19 17:55   ` [PATCH v3 42/44] t5300: pass --object-format to git index-pack brian m. carlson
2020-06-19 17:56   ` [PATCH v3 43/44] bundle: detect hash algorithm when reading refs brian m. carlson
2020-06-19 17:56   ` [PATCH v3 44/44] remote-testgit: adapt for object-format brian m. carlson
2020-06-19 21:09   ` [PATCH v3 00/44] SHA-256 part 2/3: protocol functionality Junio C Hamano
2020-06-20  1:33     ` brian m. carlson

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