87 lines
3.0 KiB
C
87 lines
3.0 KiB
C
// Copyright (c) 2020 Cesanta Software Limited
|
|
// All rights reserved
|
|
//
|
|
// Example HTTP reverse proxy
|
|
// 1. Run `make`. This builds and starts a proxy on port 8000
|
|
// 2. Start your browser, go to https://localhost:8000
|
|
//
|
|
// To enable SSL/TLS, see https://mongoose.ws/tutorials/tls/#how-to-build
|
|
|
|
#include "mongoose.h"
|
|
|
|
static const char *s_backend_url =
|
|
#if MG_ENABLE_MBEDTLS || MG_ENABLE_OPENSSL
|
|
"https://cesanta.com";
|
|
#else
|
|
"http://info.cern.ch";
|
|
#endif
|
|
static const char *s_listen_url = "http://localhost:8000";
|
|
|
|
// Forward client request to the backend connection, rewriting the Host header
|
|
static void forward_request(struct mg_http_message *hm,
|
|
struct mg_connection *c) {
|
|
size_t i, max = sizeof(hm->headers) / sizeof(hm->headers[0]);
|
|
struct mg_str host = mg_url_host(s_backend_url);
|
|
mg_printf(c, "%.*s\r\n",
|
|
(int) (hm->proto.ptr + hm->proto.len - hm->message.ptr),
|
|
hm->message.ptr);
|
|
for (i = 0; i < max && hm->headers[i].name.len > 0; i++) {
|
|
struct mg_str *k = &hm->headers[i].name, *v = &hm->headers[i].value;
|
|
if (mg_strcmp(*k, mg_str("Host")) == 0) v = &host;
|
|
mg_printf(c, "%.*s: %.*s\r\n", (int) k->len, k->ptr, (int) v->len, v->ptr);
|
|
}
|
|
mg_send(c, "\r\n", 2);
|
|
mg_send(c, hm->body.ptr, hm->body.len);
|
|
MG_DEBUG(("FORWARDING: %.*s %.*s", (int) hm->method.len, hm->method.ptr,
|
|
(int) hm->uri.len, hm->uri.ptr));
|
|
}
|
|
|
|
static void fn2(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
|
|
struct mg_connection *c2 = fn_data;
|
|
if (ev == MG_EV_READ) {
|
|
// All incoming data from the backend, forward to the client
|
|
if (c2 != NULL) mg_send(c2, c->recv.buf, c->recv.len);
|
|
mg_iobuf_del(&c->recv, 0, c->recv.len);
|
|
} else if (ev == MG_EV_CLOSE) {
|
|
if (c2 != NULL) c2->fn_data = NULL;
|
|
}
|
|
(void) ev_data;
|
|
}
|
|
|
|
static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
|
|
struct mg_connection *c2 = fn_data;
|
|
if (ev == MG_EV_HTTP_MSG) {
|
|
struct mg_http_message *hm = (struct mg_http_message *) ev_data;
|
|
// Client request, create backend connection Note that we're passing
|
|
// client connection `c` as fn_data for the created backend connection.
|
|
c2 = mg_connect(c->mgr, s_backend_url, fn2, c);
|
|
if (c2 == NULL) {
|
|
mg_error(c, "Cannot create backend connection");
|
|
} else {
|
|
if (mg_url_is_ssl(s_backend_url)) {
|
|
struct mg_tls_opts opts = {.ca = "ca.pem"};
|
|
mg_tls_init(c2, &opts);
|
|
}
|
|
c->fn_data = c2;
|
|
forward_request(hm, c2);
|
|
c->is_resp = 0; // process further msgs in keep-alive connection
|
|
c2->is_hexdumping = 1;
|
|
}
|
|
} else if (ev == MG_EV_CLOSE) {
|
|
if (c2 != NULL) c2->is_closing = 1;
|
|
if (c2 != NULL) c2->fn_data = NULL;
|
|
}
|
|
}
|
|
|
|
int main(void) {
|
|
struct mg_mgr mgr;
|
|
|
|
mg_log_set(MG_LL_DEBUG); // Set log level
|
|
mg_mgr_init(&mgr); // Initialise event manager
|
|
mg_http_listen(&mgr, s_listen_url, fn, NULL); // Start proxy
|
|
for (;;) mg_mgr_poll(&mgr, 1000); // Event loop
|
|
mg_mgr_free(&mgr);
|
|
|
|
return 0;
|
|
}
|