An SSL connection takes some memory when it exists and during handshakes.
We measured up to 16kB for an established endpoint, and up to 76 extra kB
during a handshake. The SSL layer stores these values into the global
struct during initialization. If other SSL libs are used, it's easy to
change these values. Anyway they'll only be used as gross estimates in
order to guess the max number of SSL conns that can be established when
memory is constrained and the limit is not set.
We'll need to know the number of SSL connections, their use and their
cost soon. In order to avoid getting tons of ifdefs everywhere, always
export SSL information in the global section. We add two flags to know
whether or not SSL is used in a frontend and in a backend.
Since commit 656c5fa7e8 ("BUILD: ssl: disable OCSP when using
boringssl) the OCSP code is bypassed when OPENSSL_IS_BORINGSSL
is defined. The correct thing to do here is to use OPENSSL_NO_OCSP
instead, which is defined for this exact purpose in
openssl/opensslfeatures.h.
This makes haproxy forward compatible if boringssl ever introduces
full OCSP support with the additional benefit that it links fine
against a OCSP-disabled openssl.
Signed-off-by: Lukas Tribus <luky-37@hotmail.com>
Lasse Birnbaum Jensen reported an issue when agent checks are used at the same
time as standard healthchecks when SSL is enabled on the server side.
The symptom is that agent checks try to communicate in SSL while it should
manage raw data. This happens because the transport layer is shared between all
kind of checks.
To fix the issue, the transport layer is now stored in each check type,
allowing to use SSL healthchecks when required, while an agent check should
always use the raw_sock implementation.
The fix must be backported to 1.5.
There's a very common openssl patch on the net meant to significantly
reduce openssl's memory usage. This patch has been provided for many
versions now, and it makes sense to add support for it given that it
is very simple. It only requires to add an extra SSL_MODE flag. Just
like for other flags, if the flag is unknown, it's unset. About 44kB
of memory may be saved per SSL session with the patch.
When memory becomes scarce and openssl refuses to allocate a new SSL
session, it is worth freeing the pools and trying again instead of
rejecting all incoming SSL connection. This can happen when some
memory usage limits have been assigned to the haproxy process using
-m or with ulimit -m/-v.
This is mostly an enhancement of previous fix and is worth backporting
to 1.5.
Some SSL context's init functions errors were not handled and
can cause a segfault due to an incomplete SSL context
initialization.
This fix must be backported to 1.5.
Bug reported by John Leach: no-sslv3 does not work using some certificates.
It appears that ssl ctx is not updated with configured options if the
CommonName of the certificate's subject is not found.
It applies only on the first cerificate of a configured bind line.
There is no security impact, because only invalid nameless certficates
are concerned.
This fix must be backported to 1.5
Adds global statements 'ssl-default-server-options' and
'ssl-default-bind-options' to force on 'server' and 'bind' lines
some ssl options.
Currently available options are 'no-sslv3', 'no-tlsv10', 'no-tlsv11',
'no-tlsv12', 'force-sslv3', 'force-tlsv10', 'force-tlsv11',
'force-tlsv12', and 'no-tls-tickets'.
Example:
global
ssl-default-server-options no-sslv3
ssl-default-bind-options no-sslv3
ssl_c_der : binary
Returns the DER formatted certificate presented by the client when the
incoming connection was made over an SSL/TLS transport layer. When used for
an ACL, the value(s) to match against can be passed in hexadecimal form.
ssl_f_der : binary
Returns the DER formatted certificate presented by the frontend when the
incoming connection was made over an SSL/TLS transport layer. When used for
an ACL, the value(s) to match against can be passed in hexadecimal form.
When building on openssl-0.9.8, since commit 23d5d37 ("MINOR: ssl: use
SSL_get_ciphers() instead of directly accessing the cipher list.") we get
the following warning :
src/ssl_sock.c: In function 'ssl_sock_prepare_ctx':
src/ssl_sock.c:1592: warning: passing argument 1 of 'SSL_CIPHER_description' discards qualifiers from pointer target type
This is because the openssl API has changed between 0.9.8 and 1.0.1 :
0.9.8: char *SSL_CIPHER_description(SSL_CIPHER *,char *buf,int size);
1.0.1: char *SSL_CIPHER_description(const SSL_CIPHER *,char *buf,int size);
So let's remove the "const" type qualifier to satisfy both versions.
Note that the fix above was backported to 1.5, so this one should as well.
There are two sample commands to get information about the presence of a
client certificate.
ssl_fc_has_crt is true if there is a certificate present in the current
connection
ssl_c_used is true if there is a certificate present in the session.
If a session has stopped and resumed, then ssl_c_used could be true, while
ssl_fc_has_crt is false.
In the client byte of the TLS TLV of Proxy Protocol V2, there is only one
bit to indicate whether a certificate is present on the connection. The
attached patch adds a second bit to indicate the presence for the session.
This maintains backward compatibility.
[wt: this should be backported to 1.5 to help maintain compatibility
between versions]
Google's boringssl has a different cipher_list, we cannot use it as
in OpenSSL. This is due to the "Equal preference cipher groups" feature:
https://boringssl.googlesource.com/boringssl/+/858a88daf27975f67d9f63e18f95645be2886bfb^!/
also see:
https://www.imperialviolet.org/2014/02/27/tlssymmetriccrypto.html
cipher_list is used in haproxy since commit f46cd6e4ec ("MEDIUM: ssl:
Add the option to use standardized DH parameters >= 1024 bits") to
check if DHE ciphers are used.
So, if boringssl is used, the patch just assumes that there is some
DHE cipher enabled. This will lead to false positives, but thats better
than compiler warnings and crashes.
This may be replaced one day by properly implementing the the new style
cipher_list, in the meantime this workaround allows to build and use
boringssl.
Signed-off-by: Lukas Tribus <luky-37@hotmail.com>
get_rfc2409_prime_1024() and friends are not available in Google's
boringssl, so use the fallback in that case.
Signed-off-by: Lukas Tribus <luky-37@hotmail.com>
Google's boringssl doesn't currently support OCSP, so
disable it if detected.
OCSP support may be reintroduced as per:
https://code.google.com/p/chromium/issues/detail?id=398677
In that case we can simply revert this commit.
Signed-off-by: Lukas Tribus <luky-37@hotmail.com>
OpenSSL does not free the DH * value returned by the callback specified with SSL_CTX_set_tmp_dh_callback(),
leading to a memory leak for SSL/TLS connections using Diffie Hellman Ephemeral key exchange.
This patch fixes the leak by allocating the DH * structs holding the DH parameters once, at configuration time.
Note: this fix must be backported to 1.5.
'ssl_sock_get_common_name' applied to a connection was also renamed
'ssl_sock_get_remote_common_name'. Currently, this function is only used
with protocol PROXYv2 to retrieve the client certificate's common name.
A further usage could be to retrieve the server certificate's common name
on an outgoing connection.
For some browsers (firefox), an expired OCSP Response causes unwanted behavior.
Haproxy stops serving OCSP response if nextupdate date minus
the supported time skew (#define OCSP_MAX_RESPONSE_TIME_SKEW) is
in the past.
The support is all based on static responses. This doesn't add any
request / response logic to HAProxy, but allows a way to update
information through the socket interface.
Currently certificates specified using "crt" or "crt-list" on "bind" lines
are loaded as PEM files.
For each PEM file, haproxy checks for the presence of file at the same path
suffixed by ".ocsp". If such file is found, support for the TLS Certificate
Status Request extension (also known as "OCSP stapling") is automatically
enabled. The content of this file is optional. If not empty, it must contain
a valid OCSP Response in DER format. In order to be valid an OCSP Response
must comply with the following rules: it has to indicate a good status,
it has to be a single response for the certificate of the PEM file, and it
has to be valid at the moment of addition. If these rules are not respected
the OCSP Response is ignored and a warning is emitted. In order to identify
which certificate an OCSP Response applies to, the issuer's certificate is
necessary. If the issuer's certificate is not found in the PEM file, it will
be loaded from a file at the same path as the PEM file suffixed by ".issuer"
if it exists otherwise it will fail with an error.
It is possible to update an OCSP Response from the unix socket using:
set ssl ocsp-response <response>
This command is used to update an OCSP Response for a certificate (see "crt"
on "bind" lines). Same controls are performed as during the initial loading of
the response. The <response> must be passed as a base64 encoded string of the
DER encoded response from the OCSP server.
Example:
openssl ocsp -issuer issuer.pem -cert server.pem \
-host ocsp.issuer.com:80 -respout resp.der
echo "set ssl ocsp-response $(base64 -w 10000 resp.der)" | \
socat stdio /var/run/haproxy.stat
This feature is automatically enabled on openssl 0.9.8h and above.
This work was performed jointly by Dirkjan Bussink of GitHub and
Emeric Brun of HAProxy Technologies.
In OpenSSL, the name of a cipher using ephemeral diffie-hellman for key
exchange can start with EDH, but also DHE, EXP-EDH or EXP1024-DHE.
We work around this issue by using the cipher's description instead of
the cipher's name.
Hopefully the description is less likely to change in the future.
When no static DH parameters are specified, this patch makes haproxy
use standardized (rfc 2409 / rfc 3526) DH parameters with prime lenghts
of 1024, 2048, 4096 or 8192 bits for DHE key exchange. The size of the
temporary/ephemeral DH key is computed as the minimum of the RSA/DSA server
key size and the value of a new option named tune.ssl.default-dh-param.
It's commonly needed to know how many SSL asymmetric keys are computed
per second on either side (frontend or backend), and to know the SSL
session reuse ratio. Now we compute these values and report them in
"show info".
This is a minor fix, but the SSL_CTX_set_options() and
SSL_CTX_set_mode() functions take a long, not an int parameter. As
SSL_OP_ALL is now (since OpenSSL 1.0.0) defined as 0x80000BFFL, I think
it is worth fixing.
This commit modifies the PROXY protocol V2 specification to support headers
longer than 255 bytes allowing for optional extensions. It implements the
PROXY protocol V2 which is a binary representation of V1. This will make
parsing more efficient for clients who will know in advance exactly how
many bytes to read. Also, it defines and implements some optional PROXY
protocol V2 extensions to send information about downstream SSL/TLS
connections. Support for PROXY protocol V1 remains unchanged.
1.5-dev24 introduced SSL_CTX_set_msg_callback(), which came with OpenSSL
0.9.7. A build attempt with an older one failed and we're still compatible
with 0.9.6 in 1.5.
Previously ssl_fc_unique_id and ssl_bc_unique_id return a string encoded
in base64 of the RFC 5929 TLS unique identifier. This patch modify those fetches
to return directly the ID in the original binary format. The user can make the
choice to encode in base64 using the converter.
i.e. : ssl_fc_unique_id,base64
ssl_f_sha1 is a binary binary fetch used to returns the SHA-1 fingerprint of
the certificate presented by the frontend when the incoming connection was
made over an SSL/TLS transport layer. This can be used to know which
certificate was chosen using SNI.
Adds ssl fetchs and ACLs for outgoinf SSL/Transport layer connection with their
docs:
ssl_bc, ssl_bc_alg_keysize, ssl_bc_cipher, ssl_bc_protocol, ssl_bc_unique_id,
ssl_bc_session_id and ssl_bc_use_keysize.
Previous patch only focused on parsing the packet right and blocking
it, so it relaxed one test on the packet length. The difference is
not usable for attacking but the logs will not report an attack for
such cases, which is probably bad. Better report all known invalid
packets cases.
Recent commit f51c698 ("MEDIUM: ssl: implement a workaround for the
OpenSSL heartbleed attack") did not always work well, because OpenSSL
is fun enough for not testing errors before sending data... So the
output sometimes contained some data.
The OpenSSL code relies on the max_send_segment value to limit the
packet length. The code ensures that a value of zero will result in
no single byte leaking. So we're forcing this instead and that
definitely fixes the issue. Note that we need to set it the hard
way since the regular API checks for valid values.
Building with a version of openssl without heartbeat gives this since
latest 29f037d ("MEDIUM: ssl: explicitly log failed handshakes after a
heartbeat") :
src/ssl_sock.c: In function 'ssl_sock_msgcbk':
src/ssl_sock.c:188: warning: unused variable 'conn'
Simply declare conn inside the ifdef. No backport is needed.
This reverts commit 9ece05f590.
Sander Klein reported an important performance regression with this
patch applied. It is not yet certain what is exactly the cause but
let's not break other setups now and sort this out after dev24.
The commit was merged into dev23, no need to backport.
Using the previous callback, it's trivial to block the heartbeat attack,
first we control the message length, then we emit an SSL error if it is
out of bounds. A special log is emitted, indicating that a heartbleed
attack was stopped so that they are not confused with other failures.
That way, haproxy can protect itself even when running on an unpatched
SSL stack. Tests performed with openssl-1.0.1c indicate a total success.
Add a callback to receive the heartbeat notification. There, we add
SSL_SOCK_RECV_HEARTBEAT flag on the ssl session if a heartbeat is seen.
If a handshake fails, we log a different message to mention the fact that
a heartbeat was seen. The test is only performed on the frontend side.
Lukas reported another OpenBSD complaint about this use of sprintf() that
I missed :
src/ssl_sock.o(.text+0x2a79): In function `bind_parse_crt':
src/ssl_sock.c:3015: warning: sprintf() is often misused, please use snprintf()
This one was even easier to handle. Note that some of these calls could
be simplified by checking the snprintf output size instead of doing the
preliminary size computation.
This patch adds standardized (rfc 2409 / rfc 3526)
DH parameters with prime lengths of 1024, 2048, 3072, 4096, 6144 and
8192 bits, based on the private key size.
The TLS unique id, or unique channel binding, is a byte string that can be
pulled from a TLS connection and it is unique to that connection. It is
defined in RFC 5929 section 3. The value is used by various upper layer
protocols as part of an extra layer of security. For example XMPP
(RFC 6120) and EST (RFC 7030).
Add the ssl_fc_unique_id keyword and corresponding sample fetch method.
Value is retrieved from OpenSSL and base64 encoded as described in RFC
5929 section 3.
This patch replace a lot of pointeur by pattern matching identifier. If
the declared ACL use all the predefined pattern matching functions, the
register function gets the functions provided by "pattern.c" and
identified by the PAT_LATCH_*.
In the case of the acl uses his own functions, they can be declared, and
the acl registration doesn't change it.
The find_smp search the smp using the value of the pat_ref_elt pointer.
The pat_find_smp_* are no longer used. The function pattern_find_smp()
known all pattern indexation, and can be found
All the pattern delete function can use her reference to the original
"struct pat_ref_elt" to find the element to be remove. The functions
pat_del_list_str() and pat_del_meth() were deleted because after
applying this modification, they have the same code than pat_del_list_ptr().
Some functions needs to change the sample associated to pattern. This
new pointer permit to return the a pointer to the sample pointer. The
caller can use or change the value.