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/*
Unix SMB/CIFS implementation.
web server startup
Copyright (C) Andrew Tridgell 2005
Copyright (C) Jelmer Vernooij 2008
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "web_server/web_server.h"
#include "../lib/util/dlinklist.h"
#include "lib/tls/tls.h"
#include "lib/events/events.h"
#include "lib/socket/netif.h"
#include "param/param.h"
NTSTATUS server_service_web_init(void);
/* don't allow connections to hang around forever */
#define HTTP_TIMEOUT 120
/*
destroy a web connection
*/
static int websrv_destructor(struct websrv_context *web)
{
return 0;
}
/*
called when a connection times out. This prevents a stuck connection
from hanging around forever
*/
static void websrv_timeout(struct tevent_context *event_context,
struct tevent_timer *te,
struct timeval t, void *private_data)
{
struct websrv_context *web = talloc_get_type(private_data, struct websrv_context);
struct stream_connection *conn = web->conn;
web->conn = NULL;
/* TODO: send a message to any running esp context on this connection
to stop running */
stream_terminate_connection(conn, "websrv_timeout: timed out");
}
/*
setup for a raw http level error
*/
void http_error(struct websrv_context *web, const char *status, const char *info)
{
char *s;
s = talloc_asprintf(web,"<HTML><HEAD><TITLE>Error %s</TITLE></HEAD><BODY><H1>Error %s</H1><pre>%s</pre><p></BODY></HTML>\r\n\r\n",
status, status, info);
if (s == NULL) {
stream_terminate_connection(web->conn, "http_error: out of memory");
return;
}
websrv_output_headers(web, status, NULL);
websrv_output(web, s, strlen(s));
}
void websrv_output_headers(struct websrv_context *web, const char *status, struct http_header *headers)
{
char *s;
DATA_BLOB b;
struct http_header *hdr;
s = talloc_asprintf(web, "HTTP/1.0 %s\r\n", status);
if (s == NULL) return;
for (hdr = headers; hdr; hdr = hdr->next) {
s = talloc_asprintf_append_buffer(s, "%s: %s\r\n", hdr->name, hdr->value);
}
s = talloc_asprintf_append_buffer(s, "\r\n");
b = web->output.content;
web->output.content = data_blob_string_const(s);
websrv_output(web, b.data, b.length);
data_blob_free(&b);
}
void websrv_output(struct websrv_context *web, void *data, size_t length)
{
data_blob_append(web, &web->output.content, data, length);
EVENT_FD_NOT_READABLE(web->conn->event.fde);
EVENT_FD_WRITEABLE(web->conn->event.fde);
web->output.output_pending = true;
}
/*
parse one line of header input
*/
NTSTATUS http_parse_header(struct websrv_context *web, const char *line)
{
if (line[0] == 0) {
web->input.end_of_headers = true;
} else if (strncasecmp(line,"GET ", 4)==0) {
web->input.url = talloc_strndup(web, &line[4], strcspn(&line[4], " \t"));
} else if (strncasecmp(line,"POST ", 5)==0) {
web->input.post_request = true;
web->input.url = talloc_strndup(web, &line[5], strcspn(&line[5], " \t"));
} else if (strchr(line, ':') == NULL) {
http_error(web, "400 Bad request", "This server only accepts GET and POST requests");
return NT_STATUS_INVALID_PARAMETER;
} else if (strncasecmp(line, "Content-Length: ", 16)==0) {
web->input.content_length = strtoul(&line[16], NULL, 10);
} else {
struct http_header *hdr = talloc_zero(web, struct http_header);
char *colon = strchr(line, ':');
if (colon == NULL) {
http_error(web, "500 Internal Server Error", "invalidly formatted header");
return NT_STATUS_INVALID_PARAMETER;
}
hdr->name = talloc_strndup(hdr, line, colon-line);
hdr->value = talloc_strdup(hdr, colon+1);
DLIST_ADD(web->input.headers, hdr);
}
/* ignore all other headers for now */
return NT_STATUS_OK;
}
/*
called when a web connection becomes readable
*/
static void websrv_recv(struct stream_connection *conn, uint16_t flags)
{
struct web_server_data *wdata;
struct websrv_context *web = talloc_get_type(conn->private_data,
struct websrv_context);
NTSTATUS status;
uint8_t buf[1024];
size_t nread;
uint8_t *p;
DATA_BLOB b;
/* not the most efficient http parser ever, but good enough for us */
status = socket_recv(conn->socket, buf, sizeof(buf), &nread);
if (NT_STATUS_IS_ERR(status)) goto failed;
if (!NT_STATUS_IS_OK(status)) return;
if (!data_blob_append(web, &web->input.partial, buf, nread))
goto failed;
/* parse any lines that are available */
b = web->input.partial;
while (!web->input.end_of_headers &&
(p=(uint8_t *)memchr(b.data, '\n', b.length))) {
const char *line = (const char *)b.data;
*p = 0;
if (p != b.data && p[-1] == '\r') {
p[-1] = 0;
}
status = http_parse_header(web, line);
if (!NT_STATUS_IS_OK(status)) return;
b.length -= (p - b.data) + 1;
b.data = p+1;
}
/* keep any remaining bytes in web->input.partial */
if (b.length == 0) {
b.data = NULL;
}
b = data_blob_talloc(web, b.data, b.length);
data_blob_free(&web->input.partial);
web->input.partial = b;
/* we finish when we have both the full headers (terminated by
a blank line) and any post data, as indicated by the
content_length */
if (web->input.end_of_headers &&
web->input.partial.length >= web->input.content_length) {
if (web->input.partial.length > web->input.content_length) {
web->input.partial.data[web->input.content_length] = 0;
}
EVENT_FD_NOT_READABLE(web->conn->event.fde);
/* the reference/unlink code here is quite subtle. It
is needed because the rendering of the web-pages, and
in particular the esp/ejs backend, is semi-async. So
we could well end up in the connection timeout code
while inside http_process_input(), but we must not
destroy the stack variables being used by that
rendering process when we handle the timeout. */
if (!talloc_reference(web->task, web)) goto failed;
wdata = talloc_get_type(web->task->private_data, struct web_server_data);
if (wdata == NULL) goto failed;
wdata->http_process_input(wdata, web);
talloc_unlink(web->task, web);
}
return;
failed:
stream_terminate_connection(conn, "websrv_recv: failed");
}
/*
called when a web connection becomes writable
*/
static void websrv_send(struct stream_connection *conn, uint16_t flags)
{
struct websrv_context *web = talloc_get_type(conn->private_data,
struct websrv_context);
NTSTATUS status;
size_t nsent;
DATA_BLOB b;
b = web->output.content;
b.data += web->output.nsent;
b.length -= web->output.nsent;
status = socket_send(conn->socket, &b, &nsent);
if (NT_STATUS_IS_ERR(status)) {
stream_terminate_connection(web->conn, "socket_send: failed");
return;
}
if (!NT_STATUS_IS_OK(status)) {
return;
}
web->output.nsent += nsent;
if (web->output.content.length == web->output.nsent) {
stream_terminate_connection(web->conn, "websrv_send: finished sending");
}
}
/*
establish a new connection to the web server
*/
static void websrv_accept(struct stream_connection *conn)
{
struct task_server *task = talloc_get_type(conn->private_data, struct task_server);
struct web_server_data *wdata = talloc_get_type(task->private_data, struct web_server_data);
struct websrv_context *web;
struct socket_context *tls_socket;
web = talloc_zero(conn, struct websrv_context);
if (web == NULL) goto failed;
web->task = task;
web->conn = conn;
conn->private_data = web;
talloc_set_destructor(web, websrv_destructor);
event_add_timed(conn->event.ctx, web,
timeval_current_ofs(HTTP_TIMEOUT, 0),
websrv_timeout, web);
/* Overwrite the socket with a (possibly) TLS socket */
tls_socket = tls_init_server(wdata->tls_params, conn->socket,
conn->event.fde, "GPHO");
/* We might not have TLS, or it might not have initilised */
if (tls_socket) {
talloc_unlink(conn, conn->socket);
talloc_steal(conn, tls_socket);
conn->socket = tls_socket;
} else {
DEBUG(3, ("TLS not available for web_server connections\n"));
}
return;
failed:
talloc_free(conn);
}
static const struct stream_server_ops web_stream_ops = {
.name = "web",
.accept_connection = websrv_accept,
.recv_handler = websrv_recv,
.send_handler = websrv_send,
};
/*
startup the web server task
*/
static void websrv_task_init(struct task_server *task)
{
NTSTATUS status;
uint16_t port = lpcfg_web_port(task->lp_ctx);
const struct model_ops *model_ops;
struct web_server_data *wdata;
task_server_set_title(task, "task[websrv]");
/* run the web server as a single process */
model_ops = process_model_startup("single");
if (!model_ops) goto failed;
/* startup the Python processor - unfortunately we can't do this
per connection as that wouldn't allow for session variables */
wdata = talloc_zero(task, struct web_server_data);
if (wdata == NULL) goto failed;
task->private_data = wdata;
if (lpcfg_interfaces(task->lp_ctx) && lpcfg_bind_interfaces_only(task->lp_ctx)) {
int num_interfaces;
int i;
struct interface *ifaces;
load_interfaces(NULL, lpcfg_interfaces(task->lp_ctx), &ifaces);
num_interfaces = iface_count(ifaces);
for(i = 0; i < num_interfaces; i++) {
const char *address = iface_n_ip(ifaces, i);
status = stream_setup_socket(task,
task->event_ctx,
task->lp_ctx, model_ops,
&web_stream_ops,
"ipv4", address,
&port, lpcfg_socket_options(task->lp_ctx),
task);
if (!NT_STATUS_IS_OK(status)) goto failed;
}
talloc_free(ifaces);
} else {
status = stream_setup_socket(task, task->event_ctx,
task->lp_ctx, model_ops,
&web_stream_ops,
"ipv4", lpcfg_socket_address(task->lp_ctx),
&port, lpcfg_socket_options(task->lp_ctx),
task);
if (!NT_STATUS_IS_OK(status)) goto failed;
}
wdata->tls_params = tls_initialise(wdata, task->lp_ctx);
if (wdata->tls_params == NULL) goto failed;
if (!wsgi_initialize(wdata)) goto failed;
return;
failed:
task_server_terminate(task, "websrv_task_init: failed to startup web server task", true);
}
/* called at smbd startup - register ourselves as a server service */
NTSTATUS server_service_web_init(void)
{
return register_server_service("web", websrv_task_init);
}
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