This avoids a TCP reset (RST) if the server initiates a connection
shutdown by sending an SSL close notify alert and then closes the TCP
connection.
For SSL connections, usually the server announces that it will close the
connection with an SSL close notify alert. curl should read this alert.
If curl does not read this alert and just closes the connection, some
operating systems close the TCP connection with an RST flag.
See RFC 1122, section 4.2.2.13
If curl reads the close notify alert, the TCP connection is closed
normally with a FIN flag.
The new code is similar to existing code in the "SSL shutdown" function:
try to read an alert (non-blocking), and ignore any read errors.
Closes#7095
... previously they were supported if a TLS library would (unexpectedly)
still support them, but from this change they will be refused already in
curl_easy_setopt(). SSLv2 and SSLv3 have been known to be insecure for
many years now.
Closes#6773
for GnuTLS, BearSSL, mbedTLS, NSS, SChannnel, Secure Transport and
wolfSSL...
Regression since 88dd1a8a11 (shipped in 7.76.0)
Reported-by: Kenneth Davidson
Reported-by: romamik om github
Fixes#6825Closes#6827
Rename it to 'httpwant' and make a cloned field in the state struct as
well for run-time updates.
Also: refuse non-supported HTTP versions. Verified with test 129.
Closes#6585
... in most cases instead of 'struct connectdata *' but in some cases in
addition to.
- We mostly operate on transfers and not connections.
- We need the transfer handle to log, store data and more. Everything in
libcurl is driven by a transfer (the CURL * in the public API).
- This work clarifies and separates the transfers from the connections
better.
- We should avoid "conn->data". Since individual connections can be used
by many transfers when multiplexing, making sure that conn->data
points to the current and correct transfer at all times is difficult
and has been notoriously error-prone over the years. The goal is to
ultimately remove the conn->data pointer for this reason.
Closes#6425
Don't reference fields that do not exist. Fixes build failure:
vtls/mbedtls.c: In function 'mbed_connect_step1':
vtls/mbedtls.c:249:54: error: 'struct connectdata' has no member named 'http_proxy'
Closes#5615
As detailed in DEPRECATE.md, the polarssl support is now removed after
having been disabled for 6 months and nobody has missed it.
The threadlock files used by mbedtls are renamed to an 'mbedtls' prefix
instead of the former 'polarssl' and the common functions that
previously were shared between mbedtls and polarssl and contained the
name 'polarssl' have now all been renamed to instead say 'mbedtls'.
Closes#4825
As soon as a TLS backend gets ALPN conformation about the specific HTTP
version it can now set the multiplex situation for the "bundle" and
trigger moving potentially queued up transfers to the CONNECT state.
If mbedtls_ssl_get_session() fails, it may still have allocated
memory that needs to be freed to avoid leaking. Call the library
API function to release session resources on this errorpath as
well as on Curl_ssl_addsessionid() errors.
Closes: #3574
Reported-by: Michał Antoniak <M.Antoniak@posnet.com>
Reviewed-by: Daniel Stenberg <daniel@haxx.se>
The function does not return the same value as snprintf() normally does,
so readers may be mislead into thinking the code works differently than
it actually does. A different function name makes this easier to detect.
Reported-by: Tomas Hoger
Assisted-by: Daniel Gustafsson
Fixes#3296Closes#3297
- Treat CURL_SSLVERSION_MAX_NONE the same as
CURL_SSLVERSION_MAX_DEFAULT. Prior to this change NONE would mean use
the minimum version also as the maximum.
This is a follow-up to 6015cef which changed the behavior of setting
the SSL version so that the requested version would only be the minimum
and not the maximum. It appears it was (mostly) implemented in OpenSSL
but not other backends. In other words CURL_SSLVERSION_TLSv1_0 used to
mean use just TLS v1.0 and now it means use TLS v1.0 *or later*.
- Fix CURL_SSLVERSION_MAX_DEFAULT for OpenSSL.
Prior to this change CURL_SSLVERSION_MAX_DEFAULT with OpenSSL was
erroneously treated as always TLS 1.3, and would cause an error if
OpenSSL was built without TLS 1.3 support.
Co-authored-by: Daniel Gustafsson
Fixes https://github.com/curl/curl/issues/2969
Closes https://github.com/curl/curl/pull/3012
... instead of previous separate struct fields, to make it easier to
extend and change individual backends without having to modify them all.
closes#2547
There is information about the compiled-in SSL backends that is really
no concern of any code other than the SSL backend itself, such as which
function (if any) implements SHA-256 summing.
And there is information that is really interesting to the user, such as
the name, or the curl_sslbackend value.
Let's factor out the latter into a publicly visible struct. This
information will be used in the upcoming API to set the SSL backend
globally.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When building software for the masses, it is sometimes not possible to
decide for all users which SSL backend is appropriate.
Git for Windows, for example, uses cURL to perform clones, fetches and
pushes via HTTPS, and some users strongly prefer OpenSSL, while other
users really need to use Secure Channel because it offers
enterprise-ready tools to manage credentials via Windows' Credential
Store.
The current Git for Windows versions use the ugly work-around of
building libcurl once with OpenSSL support and once with Secure Channel
support, and switching out the binaries in the installer depending on
the user's choice.
Needless to say, this is a super ugly workaround that actually only
works in some cases: Git for Windows also comes in a portable form, and
in a form intended for third-party applications requiring Git
functionality, in which cases this "swap out libcurl-4.dll" simply is
not an option.
Therefore, the Git for Windows project has a vested interest in teaching
cURL to make the SSL backend a *runtime* option.
This patch makes that possible.
By running ./configure with multiple --with-<backend> options, cURL will
be built with multiple backends.
For the moment, the backend can be configured using the environment
variable CURL_SSL_BACKEND (valid values are e.g. "openssl" and
"schannel").
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
So far, all of the SSL backends' private data has been declared as
part of the ssl_connect_data struct, in one big #if .. #elif .. #endif
block.
This can only work as long as the SSL backend is a compile-time option,
something we want to change in the next commits.
Therefore, let's encapsulate the exact data needed by each SSL backend
into a private struct, and let's avoid bleeding any SSL backend-specific
information into urldata.h. This is also necessary to allow multiple SSL
backends to be compiled in at the same time, as e.g. OpenSSL's and
CyaSSL's headers cannot be included in the same .c file.
To avoid too many malloc() calls, we simply append the private structs
to the connectdata struct in allocate_conn().
This requires us to take extra care of alignment issues: struct fields
often need to be aligned on certain boundaries e.g. 32-bit values need to
be stored at addresses that divide evenly by 4 (= 32 bit / 8
bit-per-byte).
We do that by assuming that no SSL backend's private data contains any
fields that need to be aligned on boundaries larger than `long long`
(typically 64-bit) would need. Under this assumption, we simply add a
dummy field of type `long long` to the `struct connectdata` struct. This
field will never be accessed but acts as a placeholder for the four
instances of ssl_backend_data instead. the size of each ssl_backend_data
struct is stored in the SSL backend-specific metadata, to allow
allocate_conn() to know how much extra space to allocate, and how to
initialize the ssl[sockindex]->backend and proxy_ssl[sockindex]->backend
pointers.
This would appear to be a little complicated at first, but is really
necessary to encapsulate the private data of each SSL backend correctly.
And we need to encapsulate thusly if we ever want to allow selecting
CyaSSL and OpenSSL at runtime, as their headers cannot be included within
the same .c file (there are just too many conflicting definitions and
declarations for that).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
At the moment, cURL's SSL backend needs to be configured at build time.
As such, it is totally okay for them to hard-code their backend-specific
data in the ssl_connect_data struct.
In preparation for making the SSL backend a runtime option, let's make
the access of said private data a bit more abstract so that it can be
adjusted later in an easy manner.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In the ongoing endeavor to abstract out all SSL backend-specific
functionality, this is the next step: Instead of hard-coding how the
different SSL backends access their internal data in getinfo.c, let's
implement backend-specific functions to do that task.
This will also allow for switching SSL backends as a runtime option.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
