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http.c
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/*
* Copyright (c) 2002-2007 Niels Provos <provos@citi.umich.edu>
* Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "event2/event-config.h"
#include "evconfig-private.h"
#ifdef EVENT__HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#ifdef EVENT__HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_IOCCOM_H
#include <sys/ioccom.h>
#endif
#ifdef EVENT__HAVE_SYS_RESOURCE_H
#include <sys/resource.h>
#endif
#ifdef EVENT__HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef EVENT__HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#ifndef _WIN32
#include <sys/socket.h>
#include <sys/stat.h>
#else
#include <winsock2.h>
#include <ws2tcpip.h>
#endif
#include <sys/queue.h>
#ifdef EVENT__HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef EVENT__HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef EVENT__HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef _WIN32
#include <winsock2.h>
#endif
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifndef _WIN32
#include <syslog.h>
#endif
#include <signal.h>
#ifdef EVENT__HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef EVENT__HAVE_FCNTL_H
#include <fcntl.h>
#endif
#undef timeout_pending
#undef timeout_initialized
#include "strlcpy-internal.h"
#include "event2/http.h"
#include "event2/event.h"
#include "event2/buffer.h"
#include "event2/bufferevent.h"
#include "event2/http_struct.h"
#include "event2/http_compat.h"
#include "event2/util.h"
#include "event2/listener.h"
#include "log-internal.h"
#include "util-internal.h"
#include "http-internal.h"
#include "mm-internal.h"
#include "bufferevent-internal.h"
#ifndef EVENT__HAVE_GETNAMEINFO
#define NI_MAXSERV 32
#define NI_MAXHOST 1025
#ifndef NI_NUMERICHOST
#define NI_NUMERICHOST 1
#endif
#ifndef NI_NUMERICSERV
#define NI_NUMERICSERV 2
#endif
static int
fake_getnameinfo(const struct sockaddr *sa, size_t salen, char *host,
size_t hostlen, char *serv, size_t servlen, int flags)
{
struct sockaddr_in *sin = (struct sockaddr_in *)sa;
if (serv != NULL) {
char tmpserv[16];
evutil_snprintf(tmpserv, sizeof(tmpserv),
"%d", ntohs(sin->sin_port));
if (strlcpy(serv, tmpserv, servlen) >= servlen)
return (-1);
}
if (host != NULL) {
if (flags & NI_NUMERICHOST) {
if (strlcpy(host, inet_ntoa(sin->sin_addr),
hostlen) >= hostlen)
return (-1);
else
return (0);
} else {
struct hostent *hp;
hp = gethostbyaddr((char *)&sin->sin_addr,
sizeof(struct in_addr), AF_INET);
if (hp == NULL)
return (-2);
if (strlcpy(host, hp->h_name, hostlen) >= hostlen)
return (-1);
else
return (0);
}
}
return (0);
}
#endif
#define REQ_VERSION_BEFORE(req, major_v, minor_v) \
((req)->major < (major_v) || \
((req)->major == (major_v) && (req)->minor < (minor_v)))
#define REQ_VERSION_ATLEAST(req, major_v, minor_v) \
((req)->major > (major_v) || \
((req)->major == (major_v) && (req)->minor >= (minor_v)))
#ifndef MIN
#define MIN(a,b) (((a)<(b))?(a):(b))
#endif
extern int debug;
static evutil_socket_t bind_socket_ai(struct evutil_addrinfo *, int reuse);
static evutil_socket_t bind_socket(const char *, ev_uint16_t, int reuse);
static void name_from_addr(struct sockaddr *, ev_socklen_t, char **, char **);
static struct evhttp_uri *evhttp_uri_parse_authority(char *source_uri);
static int evhttp_associate_new_request_with_connection(
struct evhttp_connection *evcon);
static void evhttp_connection_start_detectclose(
struct evhttp_connection *evcon);
static void evhttp_connection_stop_detectclose(
struct evhttp_connection *evcon);
static void evhttp_request_dispatch(struct evhttp_connection* evcon);
static void evhttp_read_firstline(struct evhttp_connection *evcon,
struct evhttp_request *req);
static void evhttp_read_header(struct evhttp_connection *evcon,
struct evhttp_request *req);
static int evhttp_add_header_internal(struct evkeyvalq *headers,
const char *key, const char *value);
static const char *evhttp_response_phrase_internal(int code);
static void evhttp_get_request(struct evhttp *, evutil_socket_t, struct sockaddr *, ev_socklen_t);
static void evhttp_write_buffer(struct evhttp_connection *,
void (*)(struct evhttp_connection *, void *), void *);
static void evhttp_make_header(struct evhttp_connection *, struct evhttp_request *);
/* callbacks for bufferevent */
static void evhttp_read_cb(struct bufferevent *, void *);
static void evhttp_write_cb(struct bufferevent *, void *);
static void evhttp_error_cb(struct bufferevent *bufev, short what, void *arg);
static int evhttp_find_vhost(struct evhttp *http, struct evhttp **outhttp,
const char *hostname);
#ifndef EVENT__HAVE_STRSEP
/* strsep replacement for platforms that lack it. Only works if
* del is one character long. */
static char *
strsep(char **s, const char *del)
{
char *d, *tok;
EVUTIL_ASSERT(strlen(del) == 1);
if (!s || !*s)
return NULL;
tok = *s;
d = strstr(tok, del);
if (d) {
*d = '\0';
*s = d + 1;
} else
*s = NULL;
return tok;
}
#endif
static size_t
html_replace(const char ch, const char **escaped)
{
switch (ch) {
case '<':
*escaped = "<";
return 4;
case '>':
*escaped = ">";
return 4;
case '"':
*escaped = """;
return 6;
case '\'':
*escaped = "'";
return 6;
case '&':
*escaped = "&";
return 5;
default:
break;
}
return 1;
}
/*
* Replaces <, >, ", ' and & with <, >, ",
* ' and & correspondingly.
*
* The returned string needs to be freed by the caller.
*/
char *
evhttp_htmlescape(const char *html)
{
size_t i;
size_t new_size = 0, old_size = 0;
char *escaped_html, *p;
if (html == NULL)
return (NULL);
old_size = strlen(html);
for (i = 0; i < old_size; ++i) {
const char *replaced = NULL;
const size_t replace_size = html_replace(html[i], &replaced);
if (replace_size > EV_SIZE_MAX - new_size) {
event_warn("%s: html_replace overflow", __func__);
return (NULL);
}
new_size += replace_size;
}
if (new_size == EV_SIZE_MAX)
return (NULL);
p = escaped_html = mm_malloc(new_size + 1);
if (escaped_html == NULL) {
event_warn("%s: malloc(%lu)", __func__,
(unsigned long)(new_size + 1));
return (NULL);
}
for (i = 0; i < old_size; ++i) {
const char *replaced = &html[i];
const size_t len = html_replace(html[i], &replaced);
memcpy(p, replaced, len);
p += len;
}
*p = '\0';
return (escaped_html);
}
/** Given an evhttp_cmd_type, returns a constant string containing the
* equivalent HTTP command, or NULL if the evhttp_command_type is
* unrecognized. */
static const char *
evhttp_method(enum evhttp_cmd_type type)
{
const char *method;
switch (type) {
case EVHTTP_REQ_GET:
method = "GET";
break;
case EVHTTP_REQ_POST:
method = "POST";
break;
case EVHTTP_REQ_HEAD:
method = "HEAD";
break;
case EVHTTP_REQ_PUT:
method = "PUT";
break;
case EVHTTP_REQ_DELETE:
method = "DELETE";
break;
case EVHTTP_REQ_OPTIONS:
method = "OPTIONS";
break;
case EVHTTP_REQ_TRACE:
method = "TRACE";
break;
case EVHTTP_REQ_CONNECT:
method = "CONNECT";
break;
case EVHTTP_REQ_PATCH:
method = "PATCH";
break;
default:
method = NULL;
break;
}
return (method);
}
/**
* Determines if a response should have a body.
* Follows the rules in RFC 2616 section 4.3.
* @return 1 if the response MUST have a body; 0 if the response MUST NOT have
* a body.
*/
static int
evhttp_response_needs_body(struct evhttp_request *req)
{
return (req->response_code != HTTP_NOCONTENT &&
req->response_code != HTTP_NOTMODIFIED &&
(req->response_code < 100 || req->response_code >= 200) &&
req->type != EVHTTP_REQ_HEAD);
}
/** Helper: called after we've added some data to an evcon's bufferevent's
* output buffer. Sets the evconn's writing-is-done callback, and puts
* the bufferevent into writing mode.
*/
static void
evhttp_write_buffer(struct evhttp_connection *evcon,
void (*cb)(struct evhttp_connection *, void *), void *arg)
{
event_debug(("%s: preparing to write buffer\n", __func__));
/* Set call back */
evcon->cb = cb;
evcon->cb_arg = arg;
/* Disable the read callback: we don't actually care about data;
* we only care about close detection. (We don't disable reading --
* EV_READ, since we *do* want to learn about any close events.) */
bufferevent_setcb(evcon->bufev,
NULL, /*read*/
evhttp_write_cb,
evhttp_error_cb,
evcon);
bufferevent_enable(evcon->bufev, EV_READ|EV_WRITE);
}
static void
evhttp_send_continue_done(struct evhttp_connection *evcon, void *arg)
{
bufferevent_disable(evcon->bufev, EV_WRITE);
}
static void
evhttp_send_continue(struct evhttp_connection *evcon,
struct evhttp_request *req)
{
bufferevent_enable(evcon->bufev, EV_WRITE);
evbuffer_add_printf(bufferevent_get_output(evcon->bufev),
"HTTP/%d.%d 100 Continue\r\n\r\n",
req->major, req->minor);
evcon->cb = evhttp_send_continue_done;
evcon->cb_arg = NULL;
bufferevent_setcb(evcon->bufev,
evhttp_read_cb,
evhttp_write_cb,
evhttp_error_cb,
evcon);
}
/** Helper: returns true iff evconn is in any connected state. */
static int
evhttp_connected(struct evhttp_connection *evcon)
{
switch (evcon->state) {
case EVCON_DISCONNECTED:
case EVCON_CONNECTING:
return (0);
case EVCON_IDLE:
case EVCON_READING_FIRSTLINE:
case EVCON_READING_HEADERS:
case EVCON_READING_BODY:
case EVCON_READING_TRAILER:
case EVCON_WRITING:
default:
return (1);
}
}
/* Create the headers needed for an outgoing HTTP request, adds them to
* the request's header list, and writes the request line to the
* connection's output buffer.
*/
static void
evhttp_make_header_request(struct evhttp_connection *evcon,
struct evhttp_request *req)
{
const char *method;
evhttp_remove_header(req->output_headers, "Proxy-Connection");
/* Generate request line */
if (!(method = evhttp_method(req->type))) {
method = "NULL";
}
evbuffer_add_printf(bufferevent_get_output(evcon->bufev),
"%s %s HTTP/%d.%d\r\n",
method, req->uri, req->major, req->minor);
/* Add the content length on a post or put request if missing */
if ((req->type == EVHTTP_REQ_POST || req->type == EVHTTP_REQ_PUT) &&
evhttp_find_header(req->output_headers, "Content-Length") == NULL){
char size[22];
evutil_snprintf(size, sizeof(size), EV_SIZE_FMT,
EV_SIZE_ARG(evbuffer_get_length(req->output_buffer)));
evhttp_add_header(req->output_headers, "Content-Length", size);
}
}
/** Return true if the list of headers in 'headers', intepreted with respect
* to flags, means that we should send a "connection: close" when the request
* is done. */
static int
evhttp_is_connection_close(int flags, struct evkeyvalq* headers)
{
if (flags & EVHTTP_PROXY_REQUEST) {
/* proxy connection */
const char *connection = evhttp_find_header(headers, "Proxy-Connection");
return (connection == NULL || evutil_ascii_strcasecmp(connection, "keep-alive") != 0);
} else {
const char *connection = evhttp_find_header(headers, "Connection");
return (connection != NULL && evutil_ascii_strcasecmp(connection, "close") == 0);
}
}
static int
evhttp_is_request_connection_close(struct evhttp_request *req)
{
return
evhttp_is_connection_close(req->flags, req->input_headers) ||
evhttp_is_connection_close(req->flags, req->output_headers);
}
/* Return true iff 'headers' contains 'Connection: keep-alive' */
static int
evhttp_is_connection_keepalive(struct evkeyvalq* headers)
{
const char *connection = evhttp_find_header(headers, "Connection");
return (connection != NULL
&& evutil_ascii_strncasecmp(connection, "keep-alive", 10) == 0);
}
/* Add a correct "Date" header to headers, unless it already has one. */
static void
evhttp_maybe_add_date_header(struct evkeyvalq *headers)
{
if (evhttp_find_header(headers, "Date") == NULL) {
char date[50];
if (sizeof(date) - evutil_date_rfc1123(date, sizeof(date), NULL) > 0) {
evhttp_add_header(headers, "Date", date);
}
}
}
/* Add a "Content-Length" header with value 'content_length' to headers,
* unless it already has a content-length or transfer-encoding header. */
static void
evhttp_maybe_add_content_length_header(struct evkeyvalq *headers,
size_t content_length)
{
if (evhttp_find_header(headers, "Transfer-Encoding") == NULL &&
evhttp_find_header(headers, "Content-Length") == NULL) {
char len[22];
evutil_snprintf(len, sizeof(len), EV_SIZE_FMT,
EV_SIZE_ARG(content_length));
evhttp_add_header(headers, "Content-Length", len);
}
}
/*
* Create the headers needed for an HTTP reply in req->output_headers,
* and write the first HTTP response for req line to evcon.
*/
static void
evhttp_make_header_response(struct evhttp_connection *evcon,
struct evhttp_request *req)
{
int is_keepalive = evhttp_is_connection_keepalive(req->input_headers);
evbuffer_add_printf(bufferevent_get_output(evcon->bufev),
"HTTP/%d.%d %d %s\r\n",
req->major, req->minor, req->response_code,
req->response_code_line);
if (req->major == 1) {
if (req->minor >= 1)
evhttp_maybe_add_date_header(req->output_headers);
/*
* if the protocol is 1.0; and the connection was keep-alive
* we need to add a keep-alive header, too.
*/
if (req->minor == 0 && is_keepalive)
evhttp_add_header(req->output_headers,
"Connection", "keep-alive");
if ((req->minor >= 1 || is_keepalive) &&
evhttp_response_needs_body(req)) {
/*
* we need to add the content length if the
* user did not give it, this is required for
* persistent connections to work.
*/
evhttp_maybe_add_content_length_header(
req->output_headers,
evbuffer_get_length(req->output_buffer));
}
}
/* Potentially add headers for unidentified content. */
if (evhttp_response_needs_body(req)) {
if (evhttp_find_header(req->output_headers,
"Content-Type") == NULL
&& evcon->http_server->default_content_type) {
evhttp_add_header(req->output_headers,
"Content-Type",
evcon->http_server->default_content_type);
}
}
/* if the request asked for a close, we send a close, too */
if (evhttp_is_connection_close(req->flags, req->input_headers)) {
evhttp_remove_header(req->output_headers, "Connection");
if (!(req->flags & EVHTTP_PROXY_REQUEST))
evhttp_add_header(req->output_headers, "Connection", "close");
evhttp_remove_header(req->output_headers, "Proxy-Connection");
}
}
enum expect { NO, CONTINUE, OTHER };
static enum expect evhttp_have_expect(struct evhttp_request *req, int input)
{
const char *expect;
struct evkeyvalq *h = input ? req->input_headers : req->output_headers;
if (!(req->kind == EVHTTP_REQUEST) || !REQ_VERSION_ATLEAST(req, 1, 1))
return NO;
expect = evhttp_find_header(h, "Expect");
if (!expect)
return NO;
return !evutil_ascii_strcasecmp(expect, "100-continue") ? CONTINUE : OTHER;
}
/** Generate all headers appropriate for sending the http request in req (or
* the response, if we're sending a response), and write them to evcon's
* bufferevent. Also writes all data from req->output_buffer */
static void
evhttp_make_header(struct evhttp_connection *evcon, struct evhttp_request *req)
{
struct evkeyval *header;
struct evbuffer *output = bufferevent_get_output(evcon->bufev);
/*
* Depending if this is a HTTP request or response, we might need to
* add some new headers or remove existing headers.
*/
if (req->kind == EVHTTP_REQUEST) {
evhttp_make_header_request(evcon, req);
} else {
evhttp_make_header_response(evcon, req);
}
TAILQ_FOREACH(header, req->output_headers, next) {
evbuffer_add_printf(output, "%s: %s\r\n",
header->key, header->value);
}
evbuffer_add(output, "\r\n", 2);
if (evhttp_have_expect(req, 0) != CONTINUE &&
evbuffer_get_length(req->output_buffer)) {
/*
* For a request, we add the POST data, for a reply, this
* is the regular data.
*/
evbuffer_add_buffer(output, req->output_buffer);
}
}
void
evhttp_connection_set_max_headers_size(struct evhttp_connection *evcon,
ev_ssize_t new_max_headers_size)
{
if (new_max_headers_size<0)
evcon->max_headers_size = EV_SIZE_MAX;
else
evcon->max_headers_size = new_max_headers_size;
}
void
evhttp_connection_set_max_body_size(struct evhttp_connection* evcon,
ev_ssize_t new_max_body_size)
{
if (new_max_body_size<0)
evcon->max_body_size = EV_UINT64_MAX;
else
evcon->max_body_size = new_max_body_size;
}
static int
evhttp_connection_incoming_fail(struct evhttp_request *req,
enum evhttp_request_error error)
{
switch (error) {
case EVREQ_HTTP_DATA_TOO_LONG:
req->response_code = HTTP_ENTITYTOOLARGE;
break;
default:
req->response_code = HTTP_BADREQUEST;
}
switch (error) {
case EVREQ_HTTP_TIMEOUT:
case EVREQ_HTTP_EOF:
/*
* these are cases in which we probably should just
* close the connection and not send a reply. this
* case may happen when a browser keeps a persistent
* connection open and we timeout on the read. when
* the request is still being used for sending, we
* need to disassociated it from the connection here.
*/
if (!req->userdone) {
/* remove it so that it will not be freed */
TAILQ_REMOVE(&req->evcon->requests, req, next);
/* indicate that this request no longer has a
* connection object
*/
req->evcon = NULL;
}
return (-1);
case EVREQ_HTTP_INVALID_HEADER:
case EVREQ_HTTP_BUFFER_ERROR:
case EVREQ_HTTP_REQUEST_CANCEL:
case EVREQ_HTTP_DATA_TOO_LONG:
default: /* xxx: probably should just error on default */
/* the callback looks at the uri to determine errors */
if (req->uri) {
mm_free(req->uri);
req->uri = NULL;
}
if (req->uri_elems) {
evhttp_uri_free(req->uri_elems);
req->uri_elems = NULL;
}
/*
* the callback needs to send a reply, once the reply has
* been send, the connection should get freed.
*/
(*req->cb)(req, req->cb_arg);
}
return (0);
}
/* Free connection ownership of which can be acquired by user using
* evhttp_request_own(). */
static inline void
evhttp_request_free_auto(struct evhttp_request *req)
{
if (!(req->flags & EVHTTP_USER_OWNED))
evhttp_request_free(req);
}
static void
evhttp_request_free_(struct evhttp_connection *evcon, struct evhttp_request *req)
{
TAILQ_REMOVE(&evcon->requests, req, next);
evhttp_request_free_auto(req);
}
/* Called when evcon has experienced a (non-recoverable? -NM) error, as
* given in error. If it's an outgoing connection, reset the connection,
* retry any pending requests, and inform the user. If it's incoming,
* delegates to evhttp_connection_incoming_fail(). */
void
evhttp_connection_fail_(struct evhttp_connection *evcon,
enum evhttp_request_error error)
{
const int errsave = EVUTIL_SOCKET_ERROR();
struct evhttp_request* req = TAILQ_FIRST(&evcon->requests);
void (*cb)(struct evhttp_request *, void *);
void *cb_arg;
void (*error_cb)(enum evhttp_request_error, void *);
void *error_cb_arg;
EVUTIL_ASSERT(req != NULL);
bufferevent_disable(evcon->bufev, EV_READ|EV_WRITE);
if (evcon->flags & EVHTTP_CON_INCOMING) {
/*
* for incoming requests, there are two different
* failure cases. it's either a network level error
* or an http layer error. for problems on the network
* layer like timeouts we just drop the connections.
* For HTTP problems, we might have to send back a
* reply before the connection can be freed.
*/
if (evhttp_connection_incoming_fail(req, error) == -1)
evhttp_connection_free(evcon);
return;
}
error_cb = req->error_cb;
error_cb_arg = req->cb_arg;
/* when the request was canceled, the callback is not executed */
if (error != EVREQ_HTTP_REQUEST_CANCEL) {
/* save the callback for later; the cb might free our object */
cb = req->cb;
cb_arg = req->cb_arg;
} else {
cb = NULL;
cb_arg = NULL;
}
/* do not fail all requests; the next request is going to get
* send over a new connection. when a user cancels a request,
* all other pending requests should be processed as normal
*/
evhttp_request_free_(evcon, req);
/* reset the connection */
evhttp_connection_reset_(evcon);
/* We are trying the next request that was queued on us */
if (TAILQ_FIRST(&evcon->requests) != NULL)
evhttp_connection_connect_(evcon);
/* The call to evhttp_connection_reset_ overwrote errno.
* Let's restore the original errno, so that the user's
* callback can have a better idea of what the error was.
*/
EVUTIL_SET_SOCKET_ERROR(errsave);
/* inform the user */
if (error_cb != NULL)
error_cb(error, error_cb_arg);
if (cb != NULL)
(*cb)(NULL, cb_arg);
}
/* Bufferevent callback: invoked when any data has been written from an
* http connection's bufferevent */
static void
evhttp_write_cb(struct bufferevent *bufev, void *arg)
{
struct evhttp_connection *evcon = arg;
/* Activate our call back */
if (evcon->cb != NULL)
(*evcon->cb)(evcon, evcon->cb_arg);
}
/**
* Advance the connection state.
* - If this is an outgoing connection, we've just processed the response;
* idle or close the connection.
* - If this is an incoming connection, we've just processed the request;
* respond.
*/
static void
evhttp_connection_done(struct evhttp_connection *evcon)
{
struct evhttp_request *req = TAILQ_FIRST(&evcon->requests);
int con_outgoing = evcon->flags & EVHTTP_CON_OUTGOING;
int free_evcon = 0;
if (con_outgoing) {
/* idle or close the connection */
int need_close = evhttp_is_request_connection_close(req);
TAILQ_REMOVE(&evcon->requests, req, next);
req->evcon = NULL;
evcon->state = EVCON_IDLE;
/* check if we got asked to close the connection */
if (need_close)
evhttp_connection_reset_(evcon);
if (TAILQ_FIRST(&evcon->requests) != NULL) {
/*
* We have more requests; reset the connection
* and deal with the next request.
*/
if (!evhttp_connected(evcon))
evhttp_connection_connect_(evcon);
else
evhttp_request_dispatch(evcon);
} else if (!need_close) {
/*
* The connection is going to be persistent, but we
* need to detect if the other side closes it.
*/
evhttp_connection_start_detectclose(evcon);
} else if ((evcon->flags & EVHTTP_CON_AUTOFREE)) {
/*
* If we have no more requests that need completion
* and we're not waiting for the connection to close
*/
free_evcon = 1;
}
} else {
/*
* incoming connection - we need to leave the request on the
* connection so that we can reply to it.
*/
evcon->state = EVCON_WRITING;
}
/* notify the user of the request */
(*req->cb)(req, req->cb_arg);
/* if this was an outgoing request, we own and it's done. so free it. */
if (con_outgoing) {
evhttp_request_free_auto(req);
}
/* If this was the last request of an outgoing connection and we're
* not waiting to receive a connection close event and we want to
* automatically free the connection. We check to ensure our request
* list is empty one last time just in case our callback added a
* new request.
*/
if (free_evcon && TAILQ_FIRST(&evcon->requests) == NULL) {
evhttp_connection_free(evcon);
}
}
/*
* Handles reading from a chunked request.
* return ALL_DATA_READ:
* all data has been read
* return MORE_DATA_EXPECTED:
* more data is expected
* return DATA_CORRUPTED:
* data is corrupted
* return REQUEST_CANCELED:
* request was canceled by the user calling evhttp_cancel_request
* return DATA_TOO_LONG:
* ran over the maximum limit
*/
static enum message_read_status
evhttp_handle_chunked_read(struct evhttp_request *req, struct evbuffer *buf)
{
if (req == NULL || buf == NULL) {
return DATA_CORRUPTED;
}
while (1) {
size_t buflen;
if ((buflen = evbuffer_get_length(buf)) == 0) {
break;
}
/* evbuffer_get_length returns size_t, but len variable is ssize_t,
* check for overflow conditions */
if (buflen > EV_SSIZE_MAX) {
return DATA_CORRUPTED;
}
if (req->ntoread < 0) {
/* Read chunk size */
ev_int64_t ntoread;
char *p = evbuffer_readln(buf, NULL, EVBUFFER_EOL_CRLF);
char *endp;
int error;
if (p == NULL)
break;
/* the last chunk is on a new line? */
if (strlen(p) == 0) {
mm_free(p);
continue;
}
ntoread = evutil_strtoll(p, &endp, 16);
error = (*p == '\0' ||
(*endp != '\0' && *endp != ' ') ||
ntoread < 0);
mm_free(p);
if (error) {
/* could not get chunk size */
return (DATA_CORRUPTED);
}
/* ntoread is signed int64, body_size is unsigned size_t, check for under/overflow conditions */
if ((ev_uint64_t)ntoread > EV_SIZE_MAX - req->body_size) {
return DATA_CORRUPTED;
}
if (req->body_size + (size_t)ntoread > req->evcon->max_body_size) {
/* failed body length test */
event_debug(("Request body is too long"));
return (DATA_TOO_LONG);
}
req->body_size += (size_t)ntoread;
req->ntoread = ntoread;
if (req->ntoread == 0) {
/* Last chunk */
return (ALL_DATA_READ);
}
continue;
}
/* req->ntoread is signed int64, len is ssize_t, based on arch,
* ssize_t could only be 32b, check for these conditions */
if (req->ntoread > EV_SSIZE_MAX) {
return DATA_CORRUPTED;
}
/* don't have enough to complete a chunk; wait for more */
if (req->ntoread > 0 && buflen < (ev_uint64_t)req->ntoread)
return (MORE_DATA_EXPECTED);
/* Completed chunk */
evbuffer_remove_buffer(buf, req->input_buffer, (size_t)req->ntoread);
req->ntoread = -1;
if (req->chunk_cb != NULL) {
req->flags |= EVHTTP_REQ_DEFER_FREE;
(*req->chunk_cb)(req, req->cb_arg);
evbuffer_drain(req->input_buffer,
evbuffer_get_length(req->input_buffer));
req->flags &= ~EVHTTP_REQ_DEFER_FREE;
if ((req->flags & EVHTTP_REQ_NEEDS_FREE) != 0) {
return (REQUEST_CANCELED);
}
}
}
return (MORE_DATA_EXPECTED);
}
static void
evhttp_read_trailer(struct evhttp_connection *evcon, struct evhttp_request *req)
{
struct evbuffer *buf = bufferevent_get_input(evcon->bufev);
switch (evhttp_parse_headers_(req, buf)) {
case DATA_CORRUPTED:
case DATA_TOO_LONG:
evhttp_connection_fail_(evcon, EVREQ_HTTP_DATA_TOO_LONG);
break;
case ALL_DATA_READ:
bufferevent_disable(evcon->bufev, EV_READ);
evhttp_connection_done(evcon);
break;
case MORE_DATA_EXPECTED:
case REQUEST_CANCELED: /* ??? */
default:
break;
}
}