When only one SSL backend is configured, it is totally unnecessary to
let multissl_init() configure the backend at runtime, we can select the
correct backend at build time already.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Let's add a compile time safe API to select an SSL backend. This
function needs to be called *before* curl_global_init(), and can be
called only once.
Side note: we do not explicitly test that it is called before
curl_global_init(), but we do verify that it is not called multiple times
(even implicitly).
If SSL is used before the function was called, it will use whatever the
CURL_SSL_BACKEND environment variable says (or default to the first
available SSL backend), and if a subsequent call to
curl_global_sslset() disagrees with the previous choice, it will fail
with CURLSSLSET_TOO_LATE.
The function also accepts an "avail" parameter to point to a (read-only)
NULL-terminated list of available backends. This comes in real handy if
an application wants to let the user choose between whatever SSL backends
the currently available libcurl has to offer: simply call
curl_global_sslset(-1, NULL, &avail);
which will return CURLSSLSET_UNKNOWN_BACKEND and populate the avail
variable to point to the relevant information to present to the user.
Just like with the HTTP/2 push functions, we have to add the function
declaration of curl_global_sslset() function to the header file
*multi.h* because VMS and OS/400 require a stable order of functions
declared in include/curl/*.h (where the header files are sorted
alphabetically). This looks a bit funny, but it cannot be helped.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
There are convenient no-op versions of the init/cleanup functions now,
no need to define private ones for axTLS.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
These functions are all available via the Curl_ssl struct now, no need
to declare them separately anymore.
As the global declarations are removed, the corresponding function
definitions are marked as file-local. The only two exceptions here are
Curl_mbedtls_shutdown() and Curl_polarssl_shutdown(): only the
declarations were removed, there are no function definitions to mark
file-local.
Please note that Curl_nss_force_init() is *still* declared globally, as
the only SSL backend-specific function, because it was introduced
specifically for the use case where cURL was compiled with
`--without-ssl --with-nss`. For details, see f3b77e561 (http_ntlm: add
support for NSS, 2010-06-27).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The _shutdown() function calls the _session_free() function; While this
is not a problem now (because schannel.h declares both functions), a
patch looming in the immediate future with make all of these functions
file-local.
So let's just move the _session_free() function's definition before it
is called.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The connect_finish() function (like many other functions after it) calls
the Curl_axtls_close() function; While this is not a problem now
(because axtls.h declares the latter function), a patch looming in the
immediate future with make all of these functions file-local.
So let's just move the Curl_axtls_close() function's definition before
it is called.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The entire idea of introducing the Curl_ssl struct to describe SSL
backends is to prepare for choosing the SSL backend at runtime.
To that end, convert all the #ifdef have_curlssl_* style conditionals
to use bit flags instead.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The SHA-256 checksumming is also an SSL backend-specific function.
Let's include it in the struct declaring the functionality of SSL
backends.
In contrast to MD5, there is no fall-back code. To indicate this, the
respective entries are NULL for those backends that offer no support for
SHA-256 checksumming.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The MD5 summing is also an SSL backend-specific function. So let's
include it, offering the previous fall-back code as a separate function
now: Curl_none_md5sum(). To allow for that, the signature had to be
changed so that an error could be returned from the implementation
(Curl_none_md5sum() can run out of memory).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This is the first step to unify the SSL backend handling. Now all the
SSL backend-specific functionality is accessed via a global instance of
the Curl_ssl struct.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The idea of introducing the Curl_ssl struct was to unify how the SSL
backends are declared and called. To this end, we now provide an
instance of the Curl_ssl struct for each and every SSL backend.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This new struct is similar in nature to Curl_handler: it will define the
functions and capabilities of all the SSL backends (where Curl_handler
defines the functions and capabilities of protocol handlers).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This patch makes the signature of the _sha256sum() functions consistent
among the SSL backends, in preparation for unifying the way all SSL
backends are accessed.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This patch makes the signature of the _data_pending() functions
consistent among the SSL backends, in preparation for unifying the way
all SSL backends are accessed.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This patch makes the signature of the _cleanup() functions consistent
among the SSL backends, in preparation for unifying the way all SSL
backends are accessed.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
... as the previous fixed length 128 bytes buffer was sometimes too
small.
Fixes#1823Closes#1831
Reported-by: Benjamin Sergeant
Assisted-by: Bill Pyne, Ray Satiro, Nick Zitzmann
clang complains:
vtls/darwinssl.c:40:8: error: extra tokens at end of #endif directive
[-Werror,-Wextra-tokens]
This breaks the darwinssl build on Travis. Fix it by making this token
a comment.
Closes https://github.com/curl/curl/pull/1734
... to make all libcurl internals able to use the same data types for
the struct members. The timeval struct differs subtly on several
platforms so it makes it cumbersome to use everywhere.
Ref: #1652Closes#1693
... causing a SIGSEGV in showit() in case the handle used to initiate
the connection has already been freed.
This commit fixes a bug introduced in curl-7_19_5-204-g5f0cae803.
Reported-by: Rob Sanders
Bug: https://bugzilla.redhat.com/1436158
- Change gnutls pointer/int macros to pointer/curl_socket_t.
Prior to this change they used long type as well.
The size of the `long` data type can be shorter than that of pointer
types. This is the case most notably on Windows.
If C99 were acceptable, we could simply use `intptr_t` here. But we
want to retain C89 compatibility.
Simply use the trick of performing pointer arithmetic with the NULL
pointer: to convert an integer `i` to a pointer, simply take the
address of the `i`th element of a hypothetical character array
starting at address NULL. To convert back, simply cast the pointer
difference.
Thanks to Jay Satiro for the initial modification to use curl_socket_t
instead of int/long.
Closes#1617
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
cyassl/ssl.h needs the macros from cyassl/options.h, so define them
before including cyassl/ssl.h the first time, which happens in
urldata.h.
This broke the build on Ubuntu Xenial, which comes with WolfSSL 3.4.8
and therefore redefines the symbols from cyassl/options.h instead of
including the header.
Closes https://github.com/curl/curl/pull/1536
The module contains a more comprehensive set of trust information than
supported by nss-pem, because libnssckbi.so also includes information
about distrusted certificates.
Reviewed-by: Kai Engert
Closes#1414
- Track when the cached encrypted data contains only a partial record
that can't be decrypted without more data (SEC_E_INCOMPLETE_MESSAGE).
- Change Curl_schannel_data_pending to return false in such a case.
Other SSL libraries have pending data functions that behave similarly.
Ref: https://github.com/curl/curl/pull/1387
Closes https://github.com/curl/curl/pull/1392
This fixes 3 warnings issued by MinGW:
1. PR_ImportTCPSocket actually has a paramter of type PROsfd instead of
PRInt32, which is 64 bits on Windows. Fixed this by including the
corresponding header file instead of redeclaring the function, which is
supported even though it is in the private include folder. [1]
2. In 64-bit mode, size_t is 64 bits while CK_ULONG is 32 bits, so an explicit
narrowing cast is needed.
3. Curl_timeleft returns time_t instead of long since commit
21aa32d30d.
[1] https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_ImportTCPSocket
Closes https://github.com/curl/curl/pull/1393
ERR_error_string with NULL parameter is not thread-safe. The library
writes the string into some static buffer. Two threads doing this at
once may clobber each other and run into problems. Switch to
ERR_error_string_n which avoids this problem and is explicitly
bounds-checked.
Also clean up some remnants of OpenSSL 0.9.5 around here. A number of
comments (fixed buffer size, explaining that ERR_error_string_n was
added in a particular version) date to when ossl_strerror tried to
support pre-ERR_error_string_n OpenSSLs.
Closes#1424
ssl_session_init was only introduced in version 1.3.8, the penultimate
version. The function only contains a memset, so replace it with that.
Suggested-by: Jay Satiro
Fixes https://github.com/curl/curl/issues/1401
... because they may include an intermediate certificate for a client
certificate and the intermediate certificate needs to be presented to
the server, no matter if we verify the peer or not.
Reported-by: thraidh
Closes#851
When UNICODE is not defined, the Curl_convert_UTF8_to_tchar macro maps
directly to its argument. As it is declared as a pointer to const and
InitializeSecurityContext expects a pointer to non-const, both MSVC and MinGW
issue a warning about implicitly casting away the const. Fix this by declaring
the variables as pointers to non-const.
Closes https://github.com/curl/curl/pull/1394
- If SSL_get_error is called but no extended error detail is available
then show that SSL_ERROR_* as a string.
Prior to this change there was some inconsistency in that case: the
SSL_ERROR_* code may or may not have been shown, or may have been shown
as unknown even if it was known.
Ref: https://github.com/curl/curl/issues/1300
Closes https://github.com/curl/curl/pull/1348
This commit introduces the CURL_SSLVERSION_MAX_* constants as well as
the --tls-max option of the curl tool.
Closes https://github.com/curl/curl/pull/1166
Mark intended fallthroughs with /* FALLTHROUGH */ so that gcc will know
it's expected and won't warn on [-Wimplicit-fallthrough=].
Closes https://github.com/curl/curl/pull/1297
In DarwinSSL the SSLSetPeerDomainName function is used to enable both
sending SNI and verifying the host. When host verification is disabled
the function cannot be called, therefore SNI is disabled as well.
Closes https://github.com/curl/curl/pull/1240
Builds with axTLS 2.1.2. This then also breaks compatibility with axTLS
< 2.1.0 (the older API)
... and fix the session_id mixup brought in 04b4ee549Fixes#1220
If the NSS code was in the middle of a non-blocking handshake and it
was asked to finish the handshake in blocking mode, it unexpectedly
continued in the non-blocking mode, which caused a FTPS connection
over CONNECT to fail with "(81) Socket not ready for send/recv".
Bug: https://bugzilla.redhat.com/1420327
The information extracted from the server certificates in step 3 is only
used when in verbose mode, and there is no error handling or validation
performed as that has already been done. Only run the certificate
information extraction when in verbose mode and libcurl was built with
verbose strings.
Closes https://github.com/curl/curl/pull/1246
- Remove the SNI disabled when host verification disabled message
since that is incorrect.
- Show a message for legacy versions of Windows <= XP that connections
may fail since those versions of WinSSL lack SNI, algorithms, etc.
Bug: https://github.com/curl/curl/pull/1240
SSL_CTX_add_extra_chain_cert takes ownership of the given certificate
while, despite the similar name, SSL_CTX_add_client_CA does not. Thus
it's best to call SSL_CTX_add_client_CA before
SSL_CTX_add_extra_chain_cert, while the code still has ownership of the
argument.
Closes https://github.com/curl/curl/pull/1236
Check for presence of gnutls_alpn_* and gnutls_ocsp_* functions during
configure instead of relying on the version number. GnuTLS has options
to turn these features off and we ca just work with with such builds
like we work with older versions.
Signed-off-by: Marcus Hoffmann <m.hoffmann@cartelsol.com>
Closes#1204
Fixed an old leftover use of the USE_SSLEAY define which would make a
socket get removed from the applications sockets to monitor when the
multi_socket API was used, leading to timeouts.
Bug: #1174
Fixes a few issues in manual wildcard cert name validation in
schannel support code for Win32 CE:
- when comparing the wildcard name to the hostname, the wildcard
character was removed from the cert name and the hostname
was checked to see if it ended with the modified cert name.
This allowed cert names like *.com to match the connection
hostname. This violates recommendations from RFC 6125.
- when the wildcard name in the certificate is longer than the
connection hostname, a buffer overread of the connection
hostname buffer would occur during the comparison of the
certificate name and the connection hostname.
ERR_PACK is an internal detail of OpenSSL. Also, when using it, a
function name must be specified which is overly specific: the test will
break whenever OpenSSL internally change things so that a different
function creates the error.
Closes#1157
vtls/gtls.c: In function ‘Curl_gtls_data_pending’:
vtls/gtls.c:1429:3: error: this ‘if’ clause does not guard... [-Werror=misleading-indentation]
if(conn->proxy_ssl[connindex].session &&
^~
vtls/gtls.c:1433:5: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘if’
return res;
* HTTPS proxies:
An HTTPS proxy receives all transactions over an SSL/TLS connection.
Once a secure connection with the proxy is established, the user agent
uses the proxy as usual, including sending CONNECT requests to instruct
the proxy to establish a [usually secure] TCP tunnel with an origin
server. HTTPS proxies protect nearly all aspects of user-proxy
communications as opposed to HTTP proxies that receive all requests
(including CONNECT requests) in vulnerable clear text.
With HTTPS proxies, it is possible to have two concurrent _nested_
SSL/TLS sessions: the "outer" one between the user agent and the proxy
and the "inner" one between the user agent and the origin server
(through the proxy). This change adds supports for such nested sessions
as well.
A secure connection with a proxy requires its own set of the usual SSL
options (their actual descriptions differ and need polishing, see TODO):
--proxy-cacert FILE CA certificate to verify peer against
--proxy-capath DIR CA directory to verify peer against
--proxy-cert CERT[:PASSWD] Client certificate file and password
--proxy-cert-type TYPE Certificate file type (DER/PEM/ENG)
--proxy-ciphers LIST SSL ciphers to use
--proxy-crlfile FILE Get a CRL list in PEM format from the file
--proxy-insecure Allow connections to proxies with bad certs
--proxy-key KEY Private key file name
--proxy-key-type TYPE Private key file type (DER/PEM/ENG)
--proxy-pass PASS Pass phrase for the private key
--proxy-ssl-allow-beast Allow security flaw to improve interop
--proxy-sslv2 Use SSLv2
--proxy-sslv3 Use SSLv3
--proxy-tlsv1 Use TLSv1
--proxy-tlsuser USER TLS username
--proxy-tlspassword STRING TLS password
--proxy-tlsauthtype STRING TLS authentication type (default SRP)
All --proxy-foo options are independent from their --foo counterparts,
except --proxy-crlfile which defaults to --crlfile and --proxy-capath
which defaults to --capath.
Curl now also supports %{proxy_ssl_verify_result} --write-out variable,
similar to the existing %{ssl_verify_result} variable.
Supported backends: OpenSSL, GnuTLS, and NSS.
* A SOCKS proxy + HTTP/HTTPS proxy combination:
If both --socks* and --proxy options are given, Curl first connects to
the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS
proxy.
TODO: Update documentation for the new APIs and --proxy-* options.
Look for "Added in 7.XXX" marks.
Now Curl_rand() is made to fail if it cannot get the necessary random
level.
Changed the proto of Curl_rand() slightly to provide a number of ints at
once.
Moved out from vtls, since it isn't a TLS function and vtls provides
Curl_ssl_random() for this to use.
Discussion: https://curl.haxx.se/mail/lib-2016-11/0119.html
- Fix GnuTLS code for CURL_SSLVERSION_TLSv1_2 that broke when the
TLS 1.3 support was added in 6ad3add.
- Homogenize across code for all backends the error message when TLS 1.3
is not available to "<backend>: TLS 1.3 is not yet supported".
- Return an error when a user-specified ssl version is unrecognized.
---
Prior to this change our code for some of the backends used the
'default' label in the switch statement (ie ver unrecognized) for
ssl.version and treated it the same as CURL_SSLVERSION_DEFAULT.
Bug: https://curl.haxx.se/mail/lib-2016-11/0048.html
Reported-by: Kamil Dudka
We're mostly saying just "curl" in lower case these days so here's a big
cleanup to adapt to this reality. A few instances are left as the
project could still formally be considered called cURL.
... to make it less likely that we forget that the function actually
does case insentive compares. Also replaced several invokes of the
function with a plain strcmp when case sensitivity is not an issue (like
comparing with "-").
Curl_select_ready() was the former API that was replaced with
Curl_select_check() a while back and the former arg setup was provided
with a define (in order to leave existing code unmodified).
Now we instead offer SOCKET_READABLE and SOCKET_WRITABLE for the most
common shortcuts where only one socket is checked. They're also more
visibly macros.
As it seems to be a rarely used cipher suite (for securely established
but _unencrypted_ connections), I believe it is fine not to provide an
alias for the misspelled variant.
LibreSSL defines `OPENSSL_VERSION_NUMBER` as `0x20000000L` for all
versions returning `LibreSSL/2.0.0` for any LibreSSL version.
This change provides a local OpenSSL_version_num function replacement
returning LIBRESSL_VERSION_NUMBER instead.
Closes#1029
The OpenSSL function CRYTPO_cleanup_all_ex_data() cannot be called
multiple times without crashing - and other libs might call it! We
basically cannot call it without risking a crash. The function is a
no-op since OpenSSL 1.1.0.
Not calling this function only risks a small memory leak with OpenSSL <
1.1.0.
Bug: https://curl.haxx.se/mail/lib-2016-09/0045.html
Reported-by: Todd Short
OpenSSL 1.0.1 and 1.0.2 build an error queue that is stored per-thread
so we need to clean it when easy handles are freed, in case the thread
will be killed in which the easy handle was used. All OpenSSL code in
libcurl should extract the error in association with the error already
so clearing this queue here should be harmless at worst.
Fixes#964
... by partially reverting f975f06033. The allocation could be made by
OpenSSL so the free must be made with OPENSSL_free() to avoid problems.
Reported-by: Harold Stuart
Fixes#1005
CURLINFO_SSL_VERIFYRESULT does not get the certificate verification
result when SSL_connect fails because of a certificate verification
error.
This fix saves the result of SSL_get_verify_result so that it is
returned by CURLINFO_SSL_VERIFYRESULT.
Closes https://github.com/curl/curl/pull/995
While noErr and errSecSuccess are defined as the same value, the API
documentation states that SecPKCS12Import() returns errSecSuccess if
there were no errors in importing. Ensure that a future change of the
defined value doesn't break (however unlikely) and be consistent with
the API docs.
- Disable ALPN on Wine.
- Don't pass input secbuffer when ALPN is disabled.
When ALPN support was added a change was made to pass an input secbuffer
to initialize the context. When ALPN is enabled the buffer contains the
ALPN information, and when it's disabled the buffer is empty. In either
case this input buffer caused problems with Wine and connections would
not complete.
Bug: https://github.com/curl/curl/issues/983
Reported-by: Christian Fillion
Serialise the call to PK11_FindSlotByName() to avoid spurious errors in
a multi-threaded environment. The underlying cause is a race condition
in nssSlot_IsTokenPresent().
Bug: https://bugzilla.mozilla.org/1297397Closes#985
Undo change introduced in d4643d6 which caused iPAddress match to be
ignored if dNSName was present but did not match.
Also, if iPAddress is present but does not match, and dNSName is not
present, fail as no-match. Prior to this change in such a case the CN
would be checked for a match.
Bug: https://github.com/curl/curl/issues/959
Reported-by: wmsch@users.noreply.github.com
In order to make MBEDTLS_DEBUG work, the debug threshold must be unequal
to 0. This patch also adds a comment how mbedtls must be compiled in
order to make debugging work, and explains the possible debug levels.
Prior to this change we called Curl_ssl_getsessionid and
Curl_ssl_addsessionid regardless of whether session ID reusing was
enabled. According to comments that is in case session ID reuse was
disabled but then later enabled.
The old way was not intuitive and probably not something users expected.
When a user disables session ID caching I'd guess they don't expect the
session ID to be cached anyway in case the caching is later enabled.
Calling QueryContextAttributes with SECPKG_ATTR_APPLICATION_PROTOCOL
fails on Windows < 8.1 so we need to disable ALPN on these OS versions.
Inspiration provide by: Daniel Seither
Closes#848Fixes#840
Sessionid cache management is inseparable from managing individual
session lifetimes. E.g. for reference-counted sessions (like those in
SChannel and OpenSSL engines) every session addition and removal
should be accompanied with refcount increment and decrement
respectively. Failing to do so synchronously leads to a race condition
that causes symptoms like use-after-free and memory corruption.
This commit:
- makes existing session cache locking explicit, thus allowing
individual engines to manage lock's scope.
- fixes OpenSSL and SChannel engines by putting refcount management
inside this lock's scope in relevant places.
- adds these explicit locking calls to other engines that use
sessionid cache to accommodate for this change. Note, however,
that it is unknown whether any of these engines could also have
this race.
Bug: https://github.com/curl/curl/issues/815Fixes#815Closes#847
Regression from the previous *printf() rearrangements, this file missed to
include the correct header to make sure snprintf() works universally.
Reported-by: Moti Avrahami
Bug: https://curl.haxx.se/mail/lib-2016-05/0196.html
