curl/lib/peer.h
Stefan Eissing bc40e09f63
lib: introduce Curl_peer
`struct Curl_peer` keeps information about a communication endpoint
together. It will replace `conn->host` and `conn->conn_to_host` and
proxyinfo host. It will also become part of `struct ssl_peer`.

It has a reference counter, so an instance can be shared between
connections and filters.

Elminiates `conn->host` and `conn->connect_to_host`, used in the
proxyinfo structures. Passed to DNS resolution and socks filters, etc.

Pass peer to http proxy and socks tunnel filters. Use peer in dns filter
and resolving. Make `Curl_peer` a member in the `struct ssl_peer`.

Add `docs/internals/PEERS.md` for documentation.

Closes #21472
2026-05-05 16:22:11 +02:00

105 lines
4.3 KiB
C

#ifndef HEADER_CURL_PEER_H
#define HEADER_CURL_PEER_H
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 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.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.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
struct Curl_scheme;
struct urlpieces;
/* if peer hostname starts with this, the peer is a unix domain socket
* path, e.g. the remainder after 'localhost'. */
#define CURL_PEER_UDS_PREFIX "localhost/"
struct Curl_peer {
const struct Curl_scheme *scheme; /* url scheme */
char *hostname; /* normalized hostname (IDN decoded when supported) */
char *zoneid; /* NULL or ipv6 zone identifier */
uint32_t refcount; /* created with 1, freed when dropping to 0 */
uint32_t scopeid; /* != 0, ipv6 scope to use */
uint16_t port;
BIT(unix_socket); /* hostname is a UDS path without the prefix */
BIT(abstract_uds); /* only TRUE when `unix_socket` also TRUE */
BIT(ipv6); /* hostname is an IPv6 address stripped of '[]' */
char user_hostname[1]; /* hostname supplied by user/url */
};
/* Create a new peer:
* - `peer->user_hostname` is the passed `hostname`
* - `peer->hostname` is the normalized `hostname` via
* + IDN conversion if it has non-ASCII characters
* + stripping of surrounding '[]' for URL formatted ipv6 addresses
* + the path alone in case of a unix domain socket, e.g. hostname
* starts with CURL_PEER_UDS_PREFIX and is longer
* Will scam for IPv6 addresses even without surrounding '[]'.
* - `zoneid` ipv6 zone identifier or NULL
* - `scopeid` ipv6 scopeid of zoneid, when known.
*/
CURLcode Curl_peer_create(struct Curl_easy *data,
const struct Curl_scheme *scheme,
const char *hostname,
uint16_t port,
struct Curl_peer **ppeer);
#ifdef USE_UNIX_SOCKETS
CURLcode Curl_peer_uds_create(const struct Curl_scheme *scheme,
const char *path,
bool abstract_unix_socket,
struct Curl_peer **ppeer);
#endif
/* Unlink any peer in `*pdest`, assign src, increase src
* refcount when not NULL. */
void Curl_peer_link(struct Curl_peer **pdest, struct Curl_peer *src);
/* Drop a reference, peer may be passed as NULL */
void Curl_peer_unlink(struct Curl_peer **ppeer);
/* TRUE if both peers are NULL or have completely same properties. */
bool Curl_peer_equal(struct Curl_peer *p1, struct Curl_peer *p2);
/* TRUE if both peers are NULL or have properties except the scheme. */
bool Curl_peer_same_destination(struct Curl_peer *p1, struct Curl_peer *p2);
CURLcode Curl_peer_from_url(CURLU *uh, struct Curl_easy *data,
uint16_t port_override,
uint32_t scopeid_override,
struct urlpieces *up,
struct Curl_peer **ppeer);
CURLcode Curl_peer_from_connect_to(struct Curl_easy *data,
const struct Curl_peer *dest,
const char *connect_to,
struct Curl_peer **ppeer);
#ifndef CURL_DISABLE_PROXY
CURLcode Curl_peer_from_proxy_url(CURLU *uh,
struct Curl_easy *data,
const char *url,
uint8_t proxytype,
struct Curl_peer **ppeer,
uint8_t *pproxytype);
#endif /* !CURL_DISABLE_PROXY */
#endif /* HEADER_CURL_PEER_H */