... 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>
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 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>
... 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
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
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
... 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
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
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
* 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.
- 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
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.
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
Only protocols that actually have a protocol registered for ALPN and NPN
should try to get that negotiated in the TLS handshake. That is only
HTTPS (well, http/1.1 and http/2) right now. Previously ALPN and NPN
would wrongly be used in all handshakes if libcurl was built with it
enabled.
Reported-by: Jay Satiro
Fixes#789
Without this workaround, NSS re-uses a session cache entry despite the
server name does not match. This causes SNI host name to differ from
the actual host name. Consequently, certain servers (e.g. github.com)
respond by 400 to such requests.
Bug: https://bugzilla.mozilla.org/1202264
This header file must be included after all header files except
memdebug.h, as it does similar memory function redefinitions and can be
similarly affected by conflicting definitions in system or dependent
library headers.
The function "free" is documented in the way that no action shall occur for
a passed null pointer. It is therefore not needed that a function caller
repeats a corresponding check.
http://stackoverflow.com/questions/18775608/free-a-null-pointer-anyway-or-check-first
This issue was fixed by using the software Coccinelle 1.0.0-rc24.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
The vtls layer now checks the return value, so it is no longer necessary
to abort if a random number cannot be provided by NSS. This also fixes
the following Coverity report:
Error: FORWARD_NULL (CWE-476):
lib/vtls/nss.c:1918: var_compare_op: Comparing "data" to null implies that "data" might be null.
lib/vtls/nss.c:1923: var_deref_model: Passing null pointer "data" to "Curl_failf", which dereferences it.
lib/sendf.c:154:3: deref_parm: Directly dereferencing parameter "data".
Correctly check for memcmp() return value (it returns 0 if the strings match).
This is not really important, since curl is going to use http/1.1 anyway, but
it's still a bug I guess.
Carrying on from commit 037cd0d991, removed the following unimplemented
instances of curlssl_close_all():
Curl_axtls_close_all()
Curl_darwinssl_close_all()
Curl_cyassl_close_all()
Curl_gskit_close_all()
Curl_gtls_close_all()
Curl_nss_close_all()
Curl_polarssl_close_all()
curl_schannel.h:123: warning: right-hand operand of comma expression
has no effect
Some instances of the curlssl_close_all() function were declared with a
void return type whilst others as int. The schannel version returned
CURLE_NOT_BUILT_IN and others simply returned zero, but in all cases the
return code was ignored by the calling function Curl_ssl_close_all().
For the time being and to keep the internal API consistent, changed all
declarations to use a void return type.
To reduce code we might want to consider removing the unimplemented
versions and use a void #define like schannel does.
- Remove SSLv3 from SSL default in darwinssl, schannel, cyassl, nss,
openssl effectively making the default TLS 1.x. axTLS is not affected
since it supports only TLS, and gnutls is not affected since it already
defaults to TLS 1.x.
- Update CURLOPT_SSLVERSION doc
To force each backend implementation to really attempt to provide proper
random. If a proper random function is missing, then we can explicitly
make use of the default one we use when TLS support is missing.
This commit makes sure it works for darwinssl, gnutls, nss and openssl.
