curl/lib/multihandle.h
Alex Rousskov cb4e2be7c6 proxy: Support HTTPS proxy and SOCKS+HTTP(s)
* 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.
2016-11-24 23:41:44 +01:00

155 lines
6.4 KiB
C

#ifndef HEADER_CURL_MULTIHANDLE_H
#define HEADER_CURL_MULTIHANDLE_H
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
***************************************************************************/
#include "conncache.h"
struct Curl_message {
/* the 'CURLMsg' is the part that is visible to the external user */
struct CURLMsg extmsg;
};
/* NOTE: if you add a state here, add the name to the statename[] array as
well!
*/
typedef enum {
CURLM_STATE_INIT, /* 0 - start in this state */
CURLM_STATE_CONNECT_PEND, /* 1 - no connections, waiting for one */
CURLM_STATE_CONNECT, /* 2 - resolve/connect has been sent off */
CURLM_STATE_WAITRESOLVE, /* 3 - awaiting the resolve to finalize */
CURLM_STATE_WAITCONNECT, /* 4 - awaiting the TCP connect to finalize */
CURLM_STATE_WAITPROXYCONNECT, /* 5 - awaiting HTTPS proxy SSL initialization
to complete and/or proxy CONNECT to
finalize */
CURLM_STATE_SENDPROTOCONNECT, /* 6 - initiate protocol connect procedure */
CURLM_STATE_PROTOCONNECT, /* 7 - completing the protocol-specific connect
phase */
CURLM_STATE_WAITDO, /* 8 - wait for our turn to send the request */
CURLM_STATE_DO, /* 9 - start send off the request (part 1) */
CURLM_STATE_DOING, /* 10 - sending off the request (part 1) */
CURLM_STATE_DO_MORE, /* 11 - send off the request (part 2) */
CURLM_STATE_DO_DONE, /* 12 - done sending off request */
CURLM_STATE_WAITPERFORM, /* 13 - wait for our turn to read the response */
CURLM_STATE_PERFORM, /* 14 - transfer data */
CURLM_STATE_TOOFAST, /* 15 - wait because limit-rate exceeded */
CURLM_STATE_DONE, /* 16 - post data transfer operation */
CURLM_STATE_COMPLETED, /* 17 - operation complete */
CURLM_STATE_MSGSENT, /* 18 - the operation complete message is sent */
CURLM_STATE_LAST /* 19 - not a true state, never use this */
} CURLMstate;
/* we support N sockets per easy handle. Set the corresponding bit to what
action we should wait for */
#define MAX_SOCKSPEREASYHANDLE 5
#define GETSOCK_READABLE (0x00ff)
#define GETSOCK_WRITABLE (0xff00)
#define CURLPIPE_ANY (CURLPIPE_HTTP1 | CURLPIPE_MULTIPLEX)
/* This is the struct known as CURLM on the outside */
struct Curl_multi {
/* First a simple identifier to easier detect if a user mix up
this multi handle with an easy handle. Set this to CURL_MULTI_HANDLE. */
long type;
/* We have a doubly-linked circular list with easy handles */
struct Curl_easy *easyp;
struct Curl_easy *easylp; /* last node */
int num_easy; /* amount of entries in the linked list above. */
int num_alive; /* amount of easy handles that are added but have not yet
reached COMPLETE state */
struct curl_llist *msglist; /* a list of messages from completed transfers */
struct curl_llist *pending; /* Curl_easys that are in the
CURLM_STATE_CONNECT_PEND state */
/* callback function and user data pointer for the *socket() API */
curl_socket_callback socket_cb;
void *socket_userp;
/* callback function and user data pointer for server push */
curl_push_callback push_cb;
void *push_userp;
/* Hostname cache */
struct curl_hash hostcache;
/* timetree points to the splay-tree of time nodes to figure out expire
times of all currently set timers */
struct Curl_tree *timetree;
/* 'sockhash' is the lookup hash for socket descriptor => easy handles (note
the pluralis form, there can be more than one easy handle waiting on the
same actual socket) */
struct curl_hash sockhash;
/* pipelining wanted bits (CURLPIPE*) */
long pipelining;
bool recheckstate; /* see Curl_multi_connchanged */
/* Shared connection cache (bundles)*/
struct conncache conn_cache;
/* This handle will be used for closing the cached connections in
curl_multi_cleanup() */
struct Curl_easy *closure_handle;
long maxconnects; /* if >0, a fixed limit of the maximum number of entries
we're allowed to grow the connection cache to */
long max_host_connections; /* if >0, a fixed limit of the maximum number
of connections per host */
long max_total_connections; /* if >0, a fixed limit of the maximum number
of connections in total */
long max_pipeline_length; /* if >0, maximum number of requests in a
pipeline */
long content_length_penalty_size; /* a connection with a
content-length bigger than
this is not considered
for pipelining */
long chunk_length_penalty_size; /* a connection with a chunk length
bigger than this is not
considered for pipelining */
struct curl_llist *pipelining_site_bl; /* List of sites that are blacklisted
from pipelining */
struct curl_llist *pipelining_server_bl; /* List of server types that are
blacklisted from pipelining */
/* timer callback and user data pointer for the *socket() API */
curl_multi_timer_callback timer_cb;
void *timer_userp;
struct timeval timer_lastcall; /* the fixed time for the timeout for the
previous callback */
};
#endif /* HEADER_CURL_MULTIHANDLE_H */