The alt-svc cache survives a call to curl_easy_reset fine, but the file
name to use for saving the cache was cleared. Now the alt-svc cache has
a copy of the file name to survive handle resets.
Added test 1908 to verify.
Reported-by: Craig Andrews
Fixes#4898Closes#4902
... as this is already done much earlier in the URL parser.
Also add test case 894 that verifies that pop3 with an encodedd CR in
the user name is rejected.
Closes#4887
Previously it would end up with an uninitialized memory buffer that
would lead to a crash or junk getting output.
Added test 1271 to verify.
Reported-by: Brian Carpenter
Closes#4786
This commit adds curl_multi_wakeup() which was previously in the TODO
list under the curl_multi_unblock name.
On some platforms and with some configurations this feature might not be
available or can fail, in these cases a new error code
(CURLM_WAKEUP_FAILURE) is returned from curl_multi_wakeup().
Fixes#4418Closes#4608
Regression from e59371a493 (7.67.0)
Added test 490, 491 and 492 to verify the functionality.
Reported-by: Kamil Dudka
Reported-by: Anderson Sasaki
Fixes#4588Closes#4591
The URL extracted with CURLINFO_EFFECTIVE_URL was returned as given as
input in most cases, which made it not get a scheme prefixed like before
if the URL was given without one, and it didn't remove dotdot sequences
etc.
Added test case 1907 to verify that this now works as intended and as
before 7.62.0.
Regression introduced in 7.62.0
Reported-by: Christophe Dervieux
Fixes#4491Closes#4493
The 'share object' only sets the storage area for cookies. The "cookie
engine" still needs to be enabled or activated using the normal cookie
options.
This caused the curl command line tool to accidentally use cookies
without having been told to, since curl switched to using shared cookies
in 7.66.0.
Test 1166 verifies
Updated test 506
Fixes#4429Closes#4434
Added unit test case 1655 to verify.
Close#4352
the code correctly finds the flaws in the old code,
if one temporarily restores doh.c to the old version.
This is a protocol violation but apparently there are legacy proprietary
servers doing this.
Added test 336 and 337 to verify.
Reported-by: Philippe Marguinaud
Closes#4339
When a username and password are provided in the URL, they were wrongly
removed from the stored URL so that subsequent uses of the same URL
wouldn't find the crendentials. This made doing HTTP auth with multiple
connections (like Digest) mishave.
Regression from 46e164069d (7.62.0)
Test case 335 added to verify.
Reported-by: Mike Crowe
Fixes#4228Closes#4229
This is only the libcurl part that provides the information. There's no
user of the parsed value. This change includes three new tests for the
parser.
Ref: #3794
As the plan has been laid out in DEPRECATED. Update docs accordingly and
verify in test 1174. Now requires the option to be set to allow HTTP/0.9
responses.
Closes#4191
If HTTPAUTH_GSSNEGOTIATE was used for a POST request and
gss_init_sec_context() failed, the POST request was sent
with empty body. This commit also restores the original
behavior of `curl --fail --negotiate`, which was changed
by commit 6c60355323.
Add regression tests 2077 and 2078 to cover this.
Fixes#3992Closes#4171
... to avoid integer overflows later when multiplying with 1000 to
convert seconds to milliseconds.
Added test 1269 to verify.
Reported-by: Jason Lee
Closes#4166
The testcase ensures that redirects to CURLPROTO_GOPHER won't be
allowed, by default, in the future. Also, curl is being used
for convenience while keeping the testcases DRY.
The expected error code is CURLE_UNSUPPORTED_PROTOCOL when the client is
redirected to CURLPROTO_GOPHER
Signed-off-by: Linos Giannopoulos <lgian@skroutz.gr>
With CURLOPT_TIMECONDITION set, a header is automatically added (e.g.
If-Modified-Since). Allow this to be replaced or suppressed with
CURLOPT_HTTPHEADER.
Fixes#4103Closes#4109
- Revert all commits related to the SASL authzid feature since the next
release will be a patch release, 7.65.1.
Prior to this change CURLOPT_SASL_AUTHZID / --sasl-authzid was destined
for the next release, assuming it would be a feature release 7.66.0.
However instead the next release will be a patch release, 7.65.1 and
will not contain any new features.
After the patch release after the reverted commits can be restored by
using cherry-pick:
git cherry-pick a14d72ca9499ff8c1cc36c2a8d520edf690
Details for all reverted commits:
Revert "os400: take care of CURLOPT_SASL_AUTHZID in curl_easy_setopt_ccsid()."
This reverts commit 0edf6907ae.
Revert "tests: Fix the line endings for the SASL alt-auth tests"
This reverts commit c2a8d52a13.
Revert "examples: Added SASL PLAIN authorisation identity (authzid) examples"
This reverts commit 8c1cc369d0.
Revert "curl: --sasl-authzid added to support CURLOPT_SASL_AUTHZID from the tool"
This reverts commit a9499ff136.
Revert "sasl: Implement SASL authorisation identity via CURLOPT_SASL_AUTHZID"
This reverts commit a14d72ca2f.
This limits all accepted input strings passed to libcurl to be less than
CURL_MAX_INPUT_LENGTH (8000000) bytes, for these API calls:
curl_easy_setopt() and curl_url_set().
The 8000000 number is arbitrary picked and is meant to detect mistakes
or abuse, not to limit actual practical use cases. By limiting the
acceptable string lengths we also reduce the risk of integer overflows
all over.
NOTE: This does not apply to `CURLOPT_POSTFIELDS`.
Test 1559 verifies.
Closes#3805
The threaded-shared-conn.c example turned into test case. Only works if
pthread was detected.
An attempt to detect future regressions such as e3a53e3efbCloses#3687
Follow-up to 8eddb8f425.
If the cookieinfo pointer is NULL there really is nothing to save.
Without this fix, we got a problem when a handle was using shared object
with cookies and is told to "FLUSH" it to file (which worked) and then
the share object was removed and when the easy handle was closed just
afterwards it has no cookieinfo and no cookies so it decided to save an
empty jar (overwriting the file just flushed).
Test 1905 now verifies that this works.
Assisted-by: Michael Wallner
Assisted-by: Marcel Raad
Closes#3621
Added Curl_resolver_kill() for all three resolver modes, which only
blocks when necessary, along with test 1592 to confirm
curl_multi_remove_handle() doesn't block unless it must.
Closes#3428Fixes#3371
This adds support for wildcard hosts in CURLOPT_RESOLVE. These are
try-last so any non-wildcard entry is resolved first. If specified,
any host not matched by another CURLOPT_RESOLVE config will use this
as fallback.
Example send a.com to 10.0.0.1 and everything else to 10.0.0.2:
curl --resolve *:443:10.0.0.2 --resolve a.com:443:10.0.0.1 \
https://a.comhttps://b.com
This is probably quite similar to using:
--connect-to a.com:443:10.0.0.1:443 --connect-to :443:10.0.0.2:443
Closes#3406
Reviewed-by: Daniel Stenberg <daniel@haxx.se>
Added CURLOPT_HTTP09_ALLOWED and --http0.9 for this purpose.
For now, both the tool and library allow HTTP/0.9 by default.
docs/DEPRECATE.md lays out the plan for when to reverse that default: 6
months after the 7.64.0 release. The options are added already now so
that applications/scripts can start using them already now.
Fixes#2873Closes#3383
This adds the CURLOPT_TRAILERDATA and CURLOPT_TRAILERFUNCTION
options that allow a callback based approach to sending trailing headers
with chunked transfers.
The test server (sws) was updated to take into account the detection of the
end of transfer in the case of trailing headers presence.
Test 1591 checks that trailing headers can be sent using libcurl.
Closes#3350
Only allow secure origins to be able to write cookies with the
'secure' flag set. This reduces the risk of non-secure origins
to influence the state of secure origins. This implements IETF
Internet-Draft draft-ietf-httpbis-cookie-alone-01 which updates
RFC6265.
Closes#2956
Reviewed-by: Daniel Stenberg <daniel@haxx.se>
... when not actually following the redirect. Otherwise we return error
for this and an application can't extract the value.
Test 1518 added to verify.
Reported-by: Pavel Pavlov
Fixes#3340Closes#3364
This adds a new unittest intended to cover the internal functions in
the urlapi code, starting with parse_port(). In order to avoid name
collisions in debug builds, parse_port() is renamed Curl_parse_port()
since it will be exported.
Reviewed-by: Daniel Stenberg <daniel@haxx.se>
Reviewed-by: Marcel Raad <Marcel.Raad@teamviewer.com>
- Include query in the path passed to generate HTTP auth.
Recent changes to use the URL API internally (46e1640, 7.62.0)
inadvertently broke authentication URIs by omitting the query.
Fixes https://github.com/curl/curl/issues/3353Closes#3356
Important for when the file is going to be read again and thus must not
contain old contents!
Adds test 327 to verify.
Reported-by: daboul on github
Fixes#3299Closes#3300
The function identifying a leading "scheme" part of the URL considered a
few letters ending with a colon to be a scheme, making something like
"short:80" to become an unknown scheme instead of a short host name and
a port number.
Extended test 1560 to verify.
Also fixed test203 to use file_pwd to make it get the correct path on
windows. Removed test 2070 since it was a duplicate of 203.
Assisted-by: Marcel Raad
Reported-by: Hagai Auro
Fixes#3220Fixes#3233Closes#3223Closes#3235
The internal buffer in infof() is limited to 2048 bytes of payload plus
an additional byte for NULL termination. Servers with very long error
messages can however cause truncation of the string, which currently
isn't very clear, and leads to badly formatted output.
This appends a "...\n" (or just "..." in case the format didn't with a
newline char) marker to the end of the string to clearly show
that it has been truncated.
Also include a unittest covering infof() to try and catch any bugs
introduced in this quite important function.
Closes#3216
Reviewed-by: Daniel Stenberg <daniel@haxx.se>
Reviewed-by: Marcel Raad <Marcel.Raad@teamviewer.com>
When not actually following the redirect and the target URL is only
stored for later retrieval, curl always accepted "non-supported"
schemes. This was a regression from 46e164069d.
Reported-by: Brad King
Fixes#3210Closes#3215
... and add "MAILINDEX".
As described in #2789, this is a suggested solution. Changing UID=xx to
actually get mail with UID xx and add "MAILINDEX" to get a mail with a
special index in the mail box (old behavior). So MAILINDEX=1 gives the
first non deleted mail in the mail box.
Fixes#2789Closes#2815
... simply because this is usually a sign of the user having omitted the
file name and the next option is instead "eaten" by the parser as a file
name.
Add test1268 to verify
Closes#2885
Deal with tiny "HTTP/0.9" (header-less) responses by checking the
status-line early, even before a full "HTTP/" is received to allow
detecting 0.9 properly.
Test 1266 and 1267 added to verify.
Fixes#2420Closes#2872
When the application just started the transfer and then stops it while
the name resolve in the background thread hasn't completed, we need to
wait for the resolve to complete and then cleanup data accordingly.
Enabled test 1553 again and added test 1590 to also check when the host
name resolves successfully.
Detected by OSS-fuzz.
Closes#1968
This avoids appending error data to already existing good data.
Test 92 is updated to match this change.
New test 1156 checks all combinations of --range/--resume, --fail,
Content-Range header and http status code 200/416.
Fixes#1163
Reported-By: Ithubg on github
Closes#2578
RFC 6265 section 4.2.1 does not set restrictions on cookie names.
This is a follow-up to commit 7f7fcd0.
Also explicitly check proper syntax of cookie name/value pair.
New test 1155 checks that cookie names are not reserved words.
Reported-By: anshnd at github
Fixes#2564Closes#2566
- Move verify_certificate functionality in schannel.c into a new
file called schannel_verify.c. Additionally, some structure defintions
from schannel.c have been moved to schannel.h to allow them to be
used in schannel_verify.c.
- Make verify_certificate functionality for Schannel available on
all versions of Windows instead of just Windows CE. verify_certificate
will be invoked on Windows CE or when the user specifies
CURLOPT_CAINFO and CURLOPT_SSL_VERIFYPEER.
- In verify_certificate, create a custom certificate chain engine that
exclusively trusts the certificate store backed by the CURLOPT_CAINFO
file.
- doc updates of --cacert/CAINFO support for schannel
- Use CERT_NAME_SEARCH_ALL_NAMES_FLAG when invoking CertGetNameString
when available. This implements a TODO in schannel.c to improve
handling of multiple SANs in a certificate. In particular, all SANs
will now be searched instead of just the first name.
- Update tool_operate.c to not search for the curl-ca-bundle.crt file
when using Schannel to maintain backward compatibility. Previously,
any curl-ca-bundle.crt file found in that search would have been
ignored by Schannel. But, with CAINFO support, the file found by
that search would have been used as the certificate store and
could cause issues for any users that have curl-ca-bundle.crt in
the search path.
- Update url.c to not set the build time CURL_CA_BUNDLE if the selected
SSL backend is Schannel. We allow setting CA location for schannel
only when explicitly specified by the user via CURLOPT_CAINFO /
--cacert.
- Add new test cases 3000 and 3001. These test cases check that the first
and last SAN, respectively, matches the connection hostname. New test
certificates have been added for these cases. For 3000, the certificate
prefix is Server-localhost-firstSAN and for 3001, the certificate
prefix is Server-localhost-secondSAN.
- Remove TODO 15.2 (Add support for custom server certificate
validation), this commit addresses it.
Closes https://github.com/curl/curl/pull/1325
This patch adds CURLOPT_DNS_SHUFFLE_ADDRESSES to explicitly request
shuffling of IP addresses returned for a hostname when there is more
than one. This is useful when the application knows that a round robin
approach is appropriate and is willing to accept the consequences of
potentially discarding some preference order returned by the system's
implementation.
Closes#1694
Refuse to operate when given path components featuring byte values lower
than 32.
Previously, inserting a %00 sequence early in the directory part when
using the 'singlecwd' ftp method could make curl write a zero byte
outside of the allocated buffer.
Test case 340 verifies.
CVE-2018-1000120
Reported-by: Duy Phan Thanh
Bug: https://curl.haxx.se/docs/adv_2018-9cd6.html
- Add new option CURLOPT_RESOLVER_START_FUNCTION to set a callback that
will be called every time before a new resolve request is started
(ie before a host is resolved) with a pointer to backend-specific
resolver data. Currently this is only useful for ares.
- Add new option CURLOPT_RESOLVER_START_DATA to set a user pointer to
pass to the resolver start callback.
Closes https://github.com/curl/curl/pull/2311
This enables users to preresolve but still take advantage of happy
eyeballs and trying multiple addresses if some are not connecting.
Ref: https://github.com/curl/curl/pull/2260
Test 319 checks proper raw mode data with non-chunked gzip
transfer-encoded server data.
Test 326 checks raw mode with chunked server data.
Bug: #2303Closes#2308
RFC 5321 4.1.1.4 specifies the CRLF terminating the DATA command
should be taken into account when chasing the <CRLF>.<CRLF> end marker.
Thus a leading dot character in data is also subject to escaping.
Tests 911 and test server are adapted to this situation.
New tests 951 and 952 check proper handling of initial dot in data.
Closes#2304
... unless CURLOPT_UNRESTRICTED_AUTH is set to allow them. This matches how
curl already handles Authorization headers created internally.
Note: this changes behavior slightly, for the sake of reducing mistakes.
Added test 317 and 318 to verify.
Reported-by: Craig de Stigter
Bug: https://curl.haxx.se/docs/adv_2018-b3bf.html
A mime tree attached to an easy handle using CURLOPT_MIMEPOST is
strongly bound to the handle: there is a pointer to the easy handle in
each item of the mime tree and following the parent pointer list
of mime items ends in a dummy part stored within the handle.
Because of this binding, a mime tree cannot be shared between different
easy handles, thus it needs to be cloned upon easy handle duplication.
There is no way for the caller to get the duplicated mime tree
handle: it is then set to be automatically destroyed upon freeing the
new easy handle.
New test 654 checks proper mime structure duplication/release.
Add a warning note in curl_mime_data_cb() documentation about sharing
user data between duplicated handles.
Closes#2235
Decoding loop implementation did not concern the case when all
received data is consumed by Brotli decoder and the size of decoded
data internally hold by Brotli decoder is greater than CURL_MAX_WRITE_SIZE.
For content with unencoded length greater than CURL_MAX_WRITE_SIZE this
can result in the loss of data at the end of content.
Closes#2194
Move curl_mime_initpart() and curl_mime_cleanpart() calls to lower-level
functions dealing with UserDefined structure contents.
This avoids memory leakages on curl-generated part mime headers.
New test 2073 checks this using the cli tool --next option: it
triggers a valgrind error if bug is present.
Bug: https://curl.haxx.se/mail/lib-2017-12/0060.html
Reported-by: Martin Galvan
- When zlib version is < 1.2.0.4, process gzip trailer before considering
extra data as an error.
- Inflate with Z_BLOCK instead of Z_SYNC_FLUSH to maximize correct data
and minimize corrupt data output.
- Do not try to restart deflate decompression in raw mode if output has
started or if the leading data is not available anymore.
- New test 232 checks inflating raw-deflated content.
Closes#2068
For pop3/imap/smtp, added test 891 to somewhat verify the pop3
case.
For this, I enhanced the pingpong test server to be able to send back
responses with LF-only instead of always using CRLF.
Closes#2150
... so that IPv6 addresses can be passed like they can for connect-to
and how they're used in URLs.
Added test 1324 to verify
Reported-by: Alex Malinovich
Fixes#2087Closes#2091
This uses the brotli external library (https://github.com/google/brotli).
Brotli becomes a feature: additional curl_version_info() bit and
structure fields are provided for it and CURLVERSION_NOW bumped.
Tests 314 and 315 check Brotli content unencoding with correct and
erroneous data.
Some tests are updated to accomodate with the now configuration dependent
parameters of the Accept-Encoding header.
This is implemented as an output streaming stack of unencoders, the last
calling the client write procedure.
New test 230 checks this feature.
Bug: https://github.com/curl/curl/pull/2002
Reported-By: Daniel Bankhead
By properly keeping track of the last entry in the list of URLs/uploads
to handle, curl now avoids many meaningless traverses of the list which
speeds up many-URL handling *MASSIVELY* (several magnitudes on 100K
URLs).
Added test 1291, to verify that it doesn't take ages - but we don't have
any detection of "too slow" command in the test suite.
Reported-by: arainchik on github
Fixes#1959Closes#2052
When imap_done() got called before a connection is setup, it would try
to "finish up" and dereffed a NULL pointer.
Test case 1553 managed to reproduce. I had to actually use a host name
to try to resolve to slow it down, as using the normal local server IP
will make libcurl get a connection in the first curl_multi_perform()
loop and then the bug doesn't trigger.
Fixes#1953
Assisted-by: Max Dymond
... fixes a memory leak with at least IMAP when remove_handle is never
called and the transfer is abruptly just abandoned early.
Test 1552 added to verify
Detected by OSS-fuzz
Assisted-by: Max Dymond
Closes#1954
... a single double quote could leave the entry path buffer without a zero
terminating byte. CVE-2017-1000254
Test 1152 added to verify.
Reported-by: Max Dymond
Bug: https://curl.haxx.se/docs/adv_20171004.html
... instead of truncating them.
There's no fixed limit for acceptable cookie names in RFC 6265, but the
entire cookie is said to be less than 4096 bytes (section 6.1). This is
also what browsers seem to implement.
We now allow max 5000 bytes cookie header. Max 4095 bytes length per
cookie name and value. Name + value together may not exceed 4096 bytes.
Added test 1151 to verify
Bug: https://curl.haxx.se/mail/lib-2017-09/0062.html
Reported-by: Kevin Smith
Closes#1894
The stub implementation is pre-loaded using LD_PRELOAD
and emulates common gssapi uses (only builds if curl is
initially built with gssapi support).
The initial tests are currently disabled for debug builds
as LD_PRELOAD is not used then.
Ref: https://github.com/curl/curl/pull/1687
Now that the form API is deprecated and not used anymore in curl tool,
a lot of its features left untested. Test 650 attempts to check all these
features not tested elsewhere.
curl_mime_encoder() is operational and documented.
curl tool -F option is extended with ";encoder=".
curl tool --libcurl option generates calls to curl_mime_encoder().
New encoder tests 648 & 649.
Test 1404 extended with an encoder specification.
Additional mime-specific tests.
Existing tests updated to reflect small differences (Expect: 100-continue,
data size change due to empty lines, etc).
Option -F headers= keyword added to tests.
test1135 disabled until the entry point order change is resolved.
New example smtp-mime.
Examples postit2 and multi-post converted from form API to mime API.
Fixes
$ valgrind --leak-check=full ~/install-curl-git/bin/curl tftp://localhost/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaz
==9752== Memcheck, a memory error detector
==9752== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==9752== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==9752== Command: /home/even/install-curl-git/bin/curl tftp://localhost/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaz
==9752==
curl: (71) TFTP file name too long
==9752==
==9752== HEAP SUMMARY:
==9752== 505 bytes in 1 blocks are definitely lost in loss record 11 of 11
==9752== at 0x4C2DB8F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==9752== by 0x4E61CED: Curl_urldecode (in /home/even/install-curl-git/lib/libcurl.so.4.4.0)
==9752== by 0x4E75868: tftp_state_machine (in /home/even/install-curl-git/lib/libcurl.so.4.4.0)
==9752== by 0x4E761B6: tftp_do (in /home/even/install-curl-git/lib/libcurl.so.4.4.0)
==9752== by 0x4E711B6: multi_runsingle (in /home/even/install-curl-git/lib/libcurl.so.4.4.0)
==9752== by 0x4E71D00: curl_multi_perform (in /home/even/install-curl-git/lib/libcurl.so.4.4.0)
==9752== by 0x4E6950D: curl_easy_perform (in /home/even/install-curl-git/lib/libcurl.so.4.4.0)
==9752== by 0x40E0B7: operate_do (in /home/even/install-curl-git/bin/curl)
==9752== by 0x40E849: operate (in /home/even/install-curl-git/bin/curl)
==9752== by 0x402693: main (in /home/even/install-curl-git/bin/curl)
Fixes https://oss-fuzz.com/v2/testcase-detail/5232311106797568
Credit to OSS Fuzz
Closes#1808
The required low-level logic was already available as part of
`libssh2` (via `LIBSSH2_FLAG_COMPRESS` `libssh2_session_flag()`[1]
option.)
This patch adds the new `libcurl` option `CURLOPT_SSH_COMPRESSION`
(boolean) and the new `curl` command-line option `--compressed-ssh`
to request this `libssh2` feature. To have compression enabled, it
is required that the SSH server supports a (zlib) compatible
compression method and that `libssh2` was built with `zlib` support
enabled.
[1] https://www.libssh2.org/libssh2_session_flag.html
Ref: https://github.com/curl/curl/issues/1732
Closes https://github.com/curl/curl/pull/1735
