Commit Graph

50 Commits

Author SHA1 Message Date
William Lallemand
8b453912ce MINOR: ssl: ssl_sock_prepare_ctx() return an error code
Rework ssl_sock_prepare_ctx() so it fills a buffer with the error
messages instead of using ha_alert()/ha_warning(). Also returns an error
code (ERR_*) instead of the number of errors.
2019-11-21 17:48:11 +01:00
Olivier Houchard
000694cf96 MINOR: ssl: Make ssl_sock_handshake() static.
ssl_sock_handshake is now only used by the ssl code itself, there's no need
to export it anymore, so make it static.
2019-06-05 18:03:38 +02:00
Willy Tarreau
c125cef6da CLEANUP: ssl: make inclusion of openssl headers safe
It's always a pain to have to stuff lots of #ifdef USE_OPENSSL around
ssl headers, it even results in some of them appearing in a random order
and multiple times just to benefit form an existing ifdef block. Let's
make these headers safe for inclusion when USE_OPENSSL is not defined,
they now perform the test themselves and do nothing if USE_OPENSSL is
not defined. This allows to remove no less than 8 such ifdef blocks
and make include blocks more readable.
2019-05-10 09:58:43 +02:00
Willy Tarreau
8d164dc568 CLEANUP: ssl: never include openssl/*.h outside of openssl-compat.h anymore
Since we're providing a compatibility layer for multiple OpenSSL
implementations and their derivatives, it is important that no C file
directly includes openssl headers but only passes via openssl-compat
instead. As a bonus this also gets rid of redundant complex rules for
inclusion of certain files (engines etc).
2019-05-10 09:36:42 +02:00
Willy Tarreau
9a1ab08160 CLEANUP: ssl-sock: use HA_OPENSSL_VERSION_NUMBER instead of OPENSSL_VERSION_NUMBER
Most tests on OPENSSL_VERSION_NUMBER have become complex and break all
the time because this number is fake for some derivatives like LibreSSL.
This patch creates a new macro, HA_OPENSSL_VERSION_NUMBER, which will
carry the real openssl version defining the compatibility level, and
this version will be adjusted depending on the variants.
2019-05-09 14:25:43 +02:00
Ilya Shipitsin
54832b97c6 BUILD: enable several LibreSSL hacks, including
SSL_SESSION_get0_id_context is introduced in LibreSSL-2.7.0
async operations are not supported by LibreSSL
early data is not supported by LibreSSL
packet_length is removed from SSL struct in LibreSSL
2019-05-06 07:26:24 +02:00
Emeric Brun
d0e095c2aa MINOR: ssl/cli: async fd io-handlers printable on show fd
This patch exports the async fd iohandlers and make them printable
doing a 'show fd' on cli.
2019-04-19 17:27:01 +02:00
Emeric Brun
9e7547740c MINOR: ssl: add support of aes256 bits ticket keys on file and cli.
Openssl switched from aes128 to aes256 since may 2016  to compute
tls ticket secrets used by default. But Haproxy still handled only
128 bits keys for both tls key file and CLI.

This patch permit the user to set aes256 keys throught CLI or
the key file (80 bytes encoded in base64) in the same way that
aes128 keys were handled (48 bytes encoded in base64):
- first 16 bytes for the key name
- next 16/32 bytes for aes 128/256 key bits key
- last 16/32 bytes for hmac 128/256 bits

Both sizes are now supported (but keys from same file must be
of the same size and can but updated via CLI only using a key of
the same size).

Note: This feature need the fix "dec func ignores padding for output
size checking."
2019-01-14 19:32:58 +01:00
Olivier Houchard
ab28a320aa MINOR: ssl: Add ssl_sock_set_alpn().
Add a new function, ssl_sock_set_alpn(), to be able to change the ALPN
for a connection, instead of relying of the one defined in the SSL_CTX.
2018-12-21 19:53:30 +01:00
Willy Tarreau
83061a820e MAJOR: chunks: replace struct chunk with struct buffer
Now all the code used to manipulate chunks uses a struct buffer instead.
The functions are still called "chunk*", and some of them will progressively
move to the generic buffer handling code as they are cleaned up.
2018-07-19 16:23:43 +02:00
Emmanuel Hocdet
253c3b7516 MINOR: connection: add proxy-v2-options authority
This patch add option PP2_TYPE_AUTHORITY to proxy protocol v2 when a TLS
connection was negotiated. In this case, authority corresponds to the sni.
2018-03-01 11:38:32 +01:00
Emmanuel Hocdet
283e004a85 MINOR: ssl: add ssl_sock_get_cert_sig function
ssl_sock_get_cert_sig can be used to report cert signature short name
to log and ppv2 (RSA-SHA256).
2018-03-01 11:34:08 +01:00
Emmanuel Hocdet
96b7834e98 MINOR: ssl: add ssl_sock_get_pkey_algo function
ssl_sock_get_pkey_algo can be used to report pkey algorithm to log
and ppv2 (RSA2048, EC256,...).
Extract pkey information is not free in ssl api (lock/alloc/free):
haproxy can use the pkey information computed in load_certificate.
Store and use this information in a SSL ex_data when available,
compute it if not (SSL multicert bundled and generated cert).
2018-03-01 11:34:05 +01:00
Christopher Faulet
16f45c87d5 BUG/MINOR: ssl/threads: Make management of the TLS ticket keys files thread-safe
A TLS ticket keys file can be updated on the CLI and used in same time. So we
need to protect it to be sure all accesses are thread-safe. Because updates are
infrequent, a R/W lock has been used.

This patch must be backported in 1.8
2018-02-19 14:15:38 +01:00
Emeric Brun
821bb9beaa MAJOR: threads/ssl: Make SSL part thread-safe
First, OpenSSL is now initialized to be thread-safe. This is done by setting 2
callbacks. The first one is ssl_locking_function. It handles the locks and
unlocks. The second one is ssl_id_function. It returns the current thread
id. During the init step, we create as much as R/W locks as needed, ie the
number returned by CRYPTO_num_locks function.

Next, The reusable SSL session in the server context is now thread-local.

Shctx is now also initialized if HAProxy is started with several threads.

And finally, a global lock has been added to protect the LRU cache used to store
generated certificates. The function ssl_sock_get_generated_cert is now
deprecated because the retrieved certificate can be removed by another threads
in same time. Instead, a new function has been added,
ssl_sock_assign_generated_cert. It must be used to search a certificate in the
cache and set it immediatly if found.
2017-10-31 13:58:32 +01:00
William Lallemand
4f45bb9c46 MEDIUM: shctx: separate ssl and shctx
This patch reorganize the shctx API in a generic storage API, separating
the shared SSL session handling from its core.

The shctx API only handles the generic data part, it does not know what
kind of data you use with it.

A shared_context is a storage structure allocated in a shared memory,
allowing its usage in a multithread or a multiprocess context.

The structure use 2 linked list, one containing the available blocks,
and another for the hot locked blocks. At initialization the available
list is filled with <maxblocks> blocks of size <blocksize>. An <extra>
space is initialized outside the list in case you need some specific
storage.

+-----------------------+--------+--------+--------+--------+----
| struct shared_context | extra  | block1 | block2 | block3 | ...
+-----------------------+--------+--------+--------+--------+----
                                 <--------  maxblocks  --------->
                                            * blocksize

The API allows to store content on several linked blocks. For example,
if you allocated blocks of 16 bytes, and you want to store an object of
60 bytes, the object will be allocated in a row of 4 blocks.

The API was made for LRU usage, each time you get an object, it pushes
the object at the end of the list. When it needs more space, it discards

The functions name have been renamed in a more logical way, the part
regarding shctx have been prefixed by shctx_ and the functions for the
shared ssl session cache have been prefixed by sh_ssl_sess_.
2017-10-31 03:49:40 +01:00
William Lallemand
ed0b5ad1aa REORG: shctx: move ssl functions to ssl_sock.c
Move the ssl callback functions of the ssl shared session cache to
ssl_sock.c. The shctx functions still needs to be separated of the ssl
tree and data.
2017-10-31 03:48:39 +01:00
Emmanuel Hocdet
01da571e21 MINOR: merge ssl_sock_get calls for log and ppv2
Merge ssl_sock_get_version and ssl_sock_get_proto_version.
Change ssl_sock_get_cipher to be used in ppv2.
2017-10-27 19:32:36 +02:00
Grant Zhang
872f9c2139 MEDIUM: ssl: add basic support for OpenSSL crypto engine
This patch adds the global 'ssl-engine' keyword. First arg is an engine
identifier followed by a list of default_algorithms the engine will
operate.

If the openssl version is too old, an error is reported when the option
is used.
2017-05-27 07:05:00 +02:00
Emmanuel Hocdet
98263291cc MAJOR: ssl: bind configuration per certificat
crt-list is extend to support ssl configuration. You can now have
such line in crt-list <file>:
mycert.pem [npn h2,http/1.1]

Support include "npn", "alpn", "verify", "ca_file", "crl_file",
"ecdhe", "ciphers" configuration and ssl options.

"crt-base" is also supported to fetch certificates.
2017-01-13 11:40:34 +01:00
Willy Tarreau
d1c5750370 CLEANUP: ssl: move tlskeys_finalize_config() to a post_check callback
tlskeys_finalize_config() was the only reason for haproxy.c to still
require ifdef and includes for ssl_sock. This one fits perfectly well
in the late initializers so it was changed to be registered with
hap_register_post_check().
2016-12-22 23:26:38 +01:00
Willy Tarreau
d9f5cca3d5 CLEANUP: connection: unexport raw_sock and ssl_sock
This way we're sure not to reuse them by accident.
2016-12-22 23:26:38 +01:00
Willy Tarreau
55d3791b46 MEDIUM: ssl_sock: implement ssl_sock_prepare_bind_conf()
Instead of hard-coding all SSL preparation in cfgparse.c, we now register
this new function as the transport layer's prepare_bind_conf() and call it
only when definied. This removes some non-obvious SSL-specific code from
cfgparse.c as well as a #ifdef.
2016-12-22 23:26:38 +01:00
Willy Tarreau
0320934f7e MEDIUM: ssl: remote the proxy argument from most functions
Most of the SSL functions used to have a proxy argument which was mostly
used to be able to emit clean errors using Alert(). First, many of them
were converted to memprintf() and don't require this pointer anymore.
Second, the rare which still need it also have either a bind_conf argument
or a server argument, both of which carry a pointer to the relevant proxy.

So let's now get rid of it, it needlessly complicates the API and certain
functions already have many arguments.
2016-12-22 23:26:38 +01:00
Christopher Faulet
635c0adec2 BUG/MINOR: ssl: Be sure to use unique serial for regenerated certificates
The serial number for a generated certificate was computed using the requested
servername, without any variable/random part. It is not a problem from the
moment it is not regenerated.

But if the cache is disabled or when the certificate is evicted from the cache,
we may need to regenerate it. It is important to not reuse the same serial
number for the new certificate. Else clients (especially browsers) trigger a
warning because 2 certificates issued by the same CA have the same serial
number.

So now, the serial is a static variable initialized with now_ms (internal date
in milliseconds) and incremented at each new certificate generation.

(Ref MPS-2031)
2016-02-09 09:04:53 +01:00
Christopher Faulet
7969a33a01 MINOR: ssl: Add support for EC for the CA used to sign generated certificates
This is done by adding EVP_PKEY_EC type in supported types for the CA private
key when we get the message digest used to sign a generated X509 certificate.
So now, we support DSA, RSA and EC private keys.

And to be sure, when the type of the private key is not directly supported, we
get its default message digest using the function
'EVP_PKEY_get_default_digest_nid'.

We also use the key of the default certificate instead of generated it. So we
are sure to use the same key type instead of always using a RSA key.
2015-10-09 12:13:12 +02:00
Christopher Faulet
77fe80c0b4 MINOR: ssl: Release Servers SSL context when HAProxy is shut down
[wt: could be backported to 1.5 as well]
2015-10-09 10:33:00 +02:00
Christopher Faulet
d2cab92e75 BUG/MINOR: ssl: fix management of the cache where forged certificates are stored
First, the LRU cache must be initialized after the configuration parsing to
correctly set its size.
Next, the function 'ssl_sock_set_generated_cert' returns -1 when an error occurs
(0 if success). In that case, the caller is responsible to free the memory
allocated for the certificate.
Finally, when a SSL certificate is generated by HAProxy but cannot be inserted
in the cache, it must be freed when the SSL connection is closed. This happens
when 'tune.ssl.ssl-ctx-cache-size' is set to 0.
2015-10-09 10:20:53 +02:00
Willy Tarreau
630764188b MINOR: ssl: provide ia function to set the SNI extension on a connection
ssl_sock_set_servername() is used to set the SNI hostname on an
outgoing connection. This function comes from code originally
provided by Christopher Faulet of Qualys.
2015-07-10 11:37:29 +02:00
Willy Tarreau
646b864fe5 CLEANUP: ssl: make ssl_sock_generated_cert_serial() take a const
It doesn't modify the input.
2015-07-07 18:09:15 +02:00
Christopher Faulet
3054880e09 MINOR: ssl: Export functions to manipulate generated certificates
Following functions are now available in the SSL public API:

  * ssl_sock_create_cert
  * ssl_sock_get_generated_cert
  * ssl_sock_set_generated_cert
  * ssl_sock_generated_cert_serial

These functions could be used to create a certificate by hand, set it in the
cache used to store generated certificates and retrieve it. Here is an example
(pseudo code):

  X509        *cacert     = ...;
  EVP_PKEY    *capkey     = ...;
  char        *servername = ...;
  unsigned int serial;

  serial = ssl_sock_generated_cert_serial(servername, strlen(servername));
  if (!ssl_sock_get_generated_cert(serial, cacert)) {
      SSL_CTX *ctx = ssl_sock_create_cert(servername, serial, cacert, capkey);
      ssl_sock_set_generated_cert(ctx, serial, cacert);
  }
2015-06-12 18:06:59 +02:00
Christopher Faulet
31af49d62b MEDIUM: ssl: Add options to forge SSL certificates
With this patch, it is possible to configure HAProxy to forge the SSL
certificate sent to a client using the SNI servername. We do it in the SNI
callback.

To enable this feature, you must pass following BIND options:

 * ca-sign-file <FILE> : This is the PEM file containing the CA certitifacte and
   the CA private key to create and sign server's certificates.

 * (optionally) ca-sign-pass <PASS>: This is the CA private key passphrase, if
   any.

 * generate-certificates: Enable the dynamic generation of certificates for a
   listener.

Because generating certificates is expensive, there is a LRU cache to store
them. Its size can be customized by setting the global parameter
'tune.ssl.ssl-ctx-cache-size'.
2015-06-12 18:06:59 +02:00
Remi Gacogne
47783ef05b MEDIUM: ssl: add the possibility to use a global DH parameters file
This patch adds the ssl-dh-param-file global setting. It sets the
default DH parameters that will be used during the SSL/TLS handshake when
ephemeral Diffie-Hellman (DHE) key exchange is used, for all "bind" lines
which do not explicitely define theirs.
2015-05-31 22:02:00 +02:00
Nenad Merdanovic
200b0facde MEDIUM: Add support for updating TLS ticket keys via socket
Until now, HAproxy needed to be restarted to change the TLS ticket
keys. With this patch, the TLS keys can be updated on a per-file
basis using the admin socket. Two new socket commands have been
introduced: "show tls-keys" and "set ssl tls-keys".

Signed-off-by: Nenad Merdanovic <nmerdan@anine.io>
2015-05-16 11:28:04 +02:00
Lukas Tribus
e4e30f7d52 BUILD: ssl: use OPENSSL_NO_OCSP to detect OCSP support
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>
2014-12-09 20:49:22 +01:00
Dave McCowan
328fb58d74 MEDIUM: connection: add new bit in Proxy Protocol V2
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]
2014-08-23 07:35:29 +02:00
Lukas Tribus
656c5fa7e8 BUILD: ssl: disable OCSP when using boringssl
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>
2014-08-18 14:33:48 +02:00
Emeric Brun
0abf836ecb BUG/MINOR: ssl: Fix external function in order not to return a pointer on an internal trash buffer.
'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.
2014-06-24 22:39:16 +02:00
Emeric Brun
4147b2ef10 MEDIUM: ssl: basic OCSP stapling support.
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.
2014-06-18 18:28:56 +02:00
David S
afb768340c MEDIUM: connection: Implement and extented PROXY Protocol V2
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.
2014-05-09 08:25:38 +02:00
Willy Tarreau
71b734c307 MINOR: cli: add more information to the "show info" output
In addition to previous outputs, we also emit the cumulated number of
connections, the cumulated number of requests, the maximum allowed
SSL connection concurrency, the current number of SSL connections and
the cumulated number of SSL connections. This will help troubleshoot
systems which experience memory shortage due to SSL.
2014-01-28 15:19:44 +01:00
Willy Tarreau
ffc3fcd6da MEDIUM: log: report SSL ciphers and version in logs using logformat %sslc/%sslv
These two new log-format tags report the SSL protocol version (%sslv) and the
SSL ciphers (%sslc) used for the connection with the client. For instance, to
append these information just after the client's IP/port address information
on an HTTP log line, use the following configuration :

    log-format %Ci:%Cp\ %sslv:%sslc\ [%t]\ %ft\ %b/%s\ %Tq/%Tw/%Tc/%Tr/%Tt\ %st\ %B\ %cc\ \ %cs\ %tsc\ %ac/%fc/%bc/%sc/%rc\ %sq/%bq\ %hr\ %hs\ %{+Q}r

It will report a line such as the following one :

    Oct 12 20:47:30 haproxy[9643]: 127.0.0.1:43602 TLSv1:AES-SHA [12/Oct/2012:20:47:30.303] stick2~ stick2/s1 7/0/12/0/19 200 145 - - ---- 0/0/0/0/0 0/0 "GET /?t=0 HTTP/1.0"
2012-10-12 20:48:51 +02:00
Emeric Brun
94324a4c87 MINOR: ssl: move ssl context init for servers from cfgparse.c to ssl_sock.c 2012-10-12 11:37:36 +02:00
Willy Tarreau
f7bc57ca6e REORG: connection: rename the data layer the "transport layer"
While working on the changes required to make the health checks use the
new connections, it started to become obvious that some naming was not
logical at all in the connections. Specifically, it is not logical to
call the "data layer" the layer which is in charge for all the handshake
and which does not yet provide a data layer once established until a
session has allocated all the required buffers.

In fact, it's more a transport layer, which makes much more sense. The
transport layer offers a medium on which data can transit, and it offers
the functions to move these data when the upper layer requests this. And
it is the upper layer which iterates over the transport layer's functions
to move data which should be called the data layer.

The use case where it's obvious is with embryonic sessions : an incoming
SSL connection is accepted. Only the connection is allocated, not the
buffers nor stream interface, etc... The connection handles the SSL
handshake by itself. Once this handshake is complete, we can't use the
data functions because the buffers and stream interface are not there
yet. Hence we have to first call a specific function to complete the
session initialization, after which we'll be able to use the data
functions. This clearly proves that SSL here is only a transport layer
and that the stream interface constitutes the data layer.

A similar change will be performed to rename app_cb => data, but the
two could not be in the same commit for obvious reasons.
2012-10-04 22:26:09 +02:00
Willy Tarreau
79eeafacb4 MEDIUM: move bind SSL parsing to ssl_sock
Registering new SSL bind keywords was not particularly handy as it required
many #ifdef in cfgparse.c. Now the code has moved to ssl_sock.c which calls
a register function for all the keywords.

Error reporting was also improved by this move, because the called functions
build an error message using memprintf(), which can span multiple lines if
needed, and each of these errors will be displayed indented in the context of
the bind line being processed. This is important when dealing with certificate
directories which can report multiple errors.
2012-09-18 16:20:01 +02:00
Willy Tarreau
2a65ff014e MEDIUM: config: replace ssl_conf by bind_conf
Some settings need to be merged per-bind config line and are not necessarily
SSL-specific. It becomes quite inconvenient to have this ssl_conf SSL-specific,
so let's replace it with something more generic.
2012-09-15 22:29:33 +02:00
Willy Tarreau
d1d5454180 REORG: split "protocols" files into protocol and listener
It was becoming confusing to have protocols and listeners in the same
files, split them.
2012-09-15 22:29:32 +02:00
Emeric Brun
fc0421fde9 MEDIUM: ssl: add support for SNI and wildcard certificates
A side effect of this change is that the "ssl" keyword on "bind" lines is now
just a boolean and that "crt" is needed to designate certificate files or
directories.

Note that much refcounting was needed to have the free() work correctly due to
the number of cert aliases which can make a context be shared by multiple names.
2012-09-10 09:27:02 +02:00
Emeric Brun
e1f38dbb44 MEDIUM: ssl: protect against client-initiated renegociation
CVE-2009-3555 suggests that client-initiated renegociation should be
prevented in the middle of data. The workaround here consists in having
the SSL layer notify our callback about a handshake occurring, which in
turn causes the connection to be marked in the error state if it was
already considered established (which means if a previous handshake was
completed). The result is that the connection with the client is immediately
aborted and any pending data are dropped.
2012-09-03 22:03:17 +02:00
Emeric Brun
4659195e31 MEDIUM: ssl: add new files ssl_sock.[ch] to provide the SSL data layer
This data layer supports socket-to-buffer and buffer-to-socket operations.
No sock-to-pipe nor pipe-to-sock functions are provided, since splicing does
not provide any benefit with data transformation. At best it could save a
memcpy() and avoid keeping a buffer allocated but that does not seem very
useful.

An init function and a close function are provided because the SSL context
needs to be allocated/freed.

A data-layer shutw() function is also provided because upon successful
shutdown, we want to store the SSL context in the cache in order to reuse
it for future connections and avoid a new key generation.

The handshake function is directly called from the connection handler.
At this point it is not certain whether this will remain this way or
if a new ->handshake callback will be added to the data layer so that
the connection handler doesn't care about SSL.

The sock-to-buf and buf-to-sock functions are all capable of enabling
the SSL handshake at any time. This also implies polling in the opposite
direction to what was expected. The upper layers must take that into
account (it is OK right now with the stream interface).
2012-09-03 20:49:14 +02:00