1 /* $NetBSD: http-connect.c,v 1.1.1.2 2021/04/07 02:43:15 christos Exp $ */
2 #include "event2/event-config.h"
3 #include <sys/cdefs.h>
4 __RCSID("$NetBSD: http-connect.c,v 1.1.1.2 2021/04/07 02:43:15 christos Exp $");
5
6 #include <event2/event.h>
7 #include <event2/http.h>
8 #include <event2/http_struct.h>
9 #include <event2/buffer.h>
10 #include <stdlib.h>
11 #include <stdio.h>
12 #include <limits.h>
13
14 #define VERIFY(cond) do { \
15 if (!(cond)) { \
16 fprintf(stderr, "[error] %s\n", #cond); \
17 exit(EXIT_FAILURE); \
18 } \
19 } while (0); \
20
21 #define URL_MAX 4096
22
23 struct connect_base
24 {
25 struct evhttp_connection *evcon;
26 struct evhttp_uri *location;
27 };
28
uri_parse(const char * str)29 static struct evhttp_uri* uri_parse(const char *str)
30 {
31 struct evhttp_uri *uri;
32 VERIFY(uri = evhttp_uri_parse(str));
33 VERIFY(evhttp_uri_get_host(uri));
34 VERIFY(evhttp_uri_get_port(uri) > 0);
35 return uri;
36 }
uri_path(struct evhttp_uri * uri,char buffer[URL_MAX])37 static char* uri_path(struct evhttp_uri *uri, char buffer[URL_MAX])
38 {
39 struct evhttp_uri *path;
40
41 VERIFY(evhttp_uri_join(uri, buffer, URL_MAX));
42
43 path = evhttp_uri_parse(buffer);
44 evhttp_uri_set_scheme(path, NULL);
45 evhttp_uri_set_userinfo(path, 0);
46 evhttp_uri_set_host(path, NULL);
47 evhttp_uri_set_port(path, -1);
48 VERIFY(evhttp_uri_join(path, buffer, URL_MAX));
49 return buffer;
50 }
uri_hostport(struct evhttp_uri * uri,char buffer[URL_MAX])51 static char* uri_hostport(struct evhttp_uri *uri, char buffer[URL_MAX])
52 {
53 VERIFY(evhttp_uri_join(uri, buffer, URL_MAX));
54 VERIFY(evhttp_uri_get_host(uri));
55 VERIFY(evhttp_uri_get_port(uri) > 0);
56 evutil_snprintf(buffer, URL_MAX, "%s:%d",
57 evhttp_uri_get_host(uri), evhttp_uri_get_port(uri));
58 return buffer;
59 }
60
get_cb(struct evhttp_request * req,void * arg)61 static void get_cb(struct evhttp_request *req, void *arg)
62 {
63 ev_ssize_t len;
64 struct evbuffer *evbuf;
65
66 VERIFY(req);
67
68 evbuf = evhttp_request_get_input_buffer(req);
69 len = evbuffer_get_length(evbuf);
70 fwrite(evbuffer_pullup(evbuf, len), len, 1, stdout);
71 evbuffer_drain(evbuf, len);
72 }
73
connect_cb(struct evhttp_request * proxy_req,void * arg)74 static void connect_cb(struct evhttp_request *proxy_req, void *arg)
75 {
76 struct connect_base *base = arg;
77 struct evhttp_connection *evcon = base->evcon;
78 struct evhttp_uri *location = base->location;
79 struct evhttp_request *req;
80 char buffer[URL_MAX];
81
82 VERIFY(proxy_req);
83 VERIFY(evcon);
84
85 req = evhttp_request_new(get_cb, NULL);
86 evhttp_add_header(req->output_headers, "Connection", "close");
87 evhttp_add_header(req->output_headers, "Host", evhttp_uri_get_host(location));
88 VERIFY(!evhttp_make_request(evcon, req, EVHTTP_REQ_GET,
89 uri_path(location, buffer)));
90 }
91
main(int argc,const char ** argv)92 int main(int argc, const char **argv)
93 {
94 char hostport[URL_MAX];
95
96 struct evhttp_uri *location;
97 struct evhttp_uri *proxy;
98
99 struct event_base *base;
100 struct evhttp_connection *evcon;
101 struct evhttp_request *req;
102
103 struct connect_base connect_base;
104
105 if (argc != 3) {
106 printf("Usage: %s proxy url\n", argv[0]);
107 return 1;
108 }
109
110 proxy = uri_parse(argv[1]);
111 location = uri_parse(argv[2]);
112
113 VERIFY(base = event_base_new());
114 VERIFY(evcon = evhttp_connection_base_new(base, NULL,
115 evhttp_uri_get_host(proxy), evhttp_uri_get_port(proxy)));
116 connect_base.evcon = evcon;
117 connect_base.location = location;
118 VERIFY(req = evhttp_request_new(connect_cb, &connect_base));
119
120 uri_hostport(location, hostport);
121 evhttp_add_header(req->output_headers, "Connection", "keep-alive");
122 evhttp_add_header(req->output_headers, "Proxy-Connection", "keep-alive");
123 evhttp_add_header(req->output_headers, "Host", hostport);
124 evhttp_make_request(evcon, req, EVHTTP_REQ_CONNECT, hostport);
125
126 event_base_dispatch(base);
127
128 evhttp_connection_free(evcon);
129 event_base_free(base);
130 evhttp_uri_free(proxy);
131 evhttp_uri_free(location);
132
133 return 0;
134 }
135