proxy_http.c

最新apache的源代码

    l1 = strlen(url);
    ent = (struct proxy_alias *)conf->raliases->elts;
    for (i = 0; i < conf->raliases->nelts; i++) {
        l2 = strlen(ent[i].real);
        if (l1 >= l2 && strncmp(ent[i].real, url, l2) == 0) {
            u = apr_pstrcat(r->pool, ent[i].fake, &url[l2], NULL);
            return ap_construct_url(r->pool, u, r);
        }
    }
    return url;
}

/* Clear all connection-based headers from the incoming headers table */
static void ap_proxy_clear_connection(apr_pool_t *p, apr_table_t *headers)
{
    const char *name;
    char *next = apr_pstrdup(p, apr_table_get(headers, "Connection"));

    apr_table_unset(headers, "Proxy-Connection");
    if (!next)
        return;

    while (*next) {
        name = next;
        while (*next && !apr_isspace(*next) && (*next != ',')) {
            ++next;
        }
        while (*next && (apr_isspace(*next) || (*next == ','))) {
            *next = '\0';
            ++next;
        }
        apr_table_unset(headers, name);
    }
    apr_table_unset(headers, "Connection");
}

static
apr_status_t ap_proxy_http_determine_connection(apr_pool_t *p, request_rec *r,
                                                proxy_http_conn_t *p_conn,
                                                conn_rec *c,
                                                proxy_server_conf *conf,
                                                apr_uri_t *uri,
                                                char **url,
                                                const char *proxyname,
                                                apr_port_t proxyport,
                                                char *server_portstr,
                                                int server_portstr_size) {
    int server_port;
    apr_status_t err;
    apr_sockaddr_t *uri_addr;
    /*
     * Break up the URL to determine the host to connect to
     */

    /* we break the URL into host, port, uri */
    if (APR_SUCCESS != apr_uri_parse(p, *url, uri)) {
        return ap_proxyerror(r, HTTP_BAD_REQUEST,
                             apr_pstrcat(p,"URI cannot be parsed: ", *url,
                                         NULL));
    }
    if (!uri->port) {
        uri->port = apr_uri_port_of_scheme(uri->scheme);
    }

    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                 "proxy: HTTP connecting %s to %s:%d", *url, uri->hostname,
                 uri->port);

    /* do a DNS lookup for the destination host */
    /* see memory note above */
    err = apr_sockaddr_info_get(&uri_addr, apr_pstrdup(c->pool, uri->hostname),
                                APR_UNSPEC, uri->port, 0, c->pool);

    /* allocate these out of the connection pool - the check on
     * r->connection->id makes sure that this string does not get accessed
     * past the connection lifetime */
    /* are we connecting directly, or via a proxy? */
    if (proxyname) {
        p_conn->name = apr_pstrdup(c->pool, proxyname);
        p_conn->port = proxyport;
        /* see memory note above */
        err = apr_sockaddr_info_get(&p_conn->addr, p_conn->name, APR_UNSPEC,
                                    p_conn->port, 0, c->pool);
    } else {
        p_conn->name = apr_pstrdup(c->pool, uri->hostname);
        p_conn->port = uri->port;
        p_conn->addr = uri_addr;
        *url = apr_pstrcat(p, uri->path, uri->query ? "?" : "",
                           uri->query ? uri->query : "",
                           uri->fragment ? "#" : "",
                           uri->fragment ? uri->fragment : "", NULL);
    }

    if (err != APR_SUCCESS) {
        return ap_proxyerror(r, HTTP_BAD_GATEWAY,
                             apr_pstrcat(p, "DNS lookup failure for: ",
                                         p_conn->name, NULL));
    }

    /* Get the server port for the Via headers */
    {
        server_port = ap_get_server_port(r);
        if (ap_is_default_port(server_port, r)) {
            strcpy(server_portstr,"");
        } else {
            apr_snprintf(server_portstr, server_portstr_size, ":%d",
                         server_port);
        }
    }

    /* check if ProxyBlock directive on this host */
    if (OK != ap_proxy_checkproxyblock(r, conf, uri_addr)) {
        return ap_proxyerror(r, HTTP_FORBIDDEN,
                             "Connect to remote machine blocked");
    }
    return OK;
}

static
apr_status_t ap_proxy_http_create_connection(apr_pool_t *p, request_rec *r,
                                             proxy_http_conn_t *p_conn,
                                             conn_rec *c, conn_rec **origin,
                                             proxy_conn_rec *backend,
                                             proxy_server_conf *conf,
                                             const char *proxyname) {
    int failed=0, new=0;
    apr_socket_t *client_socket = NULL;

    /* We have determined who to connect to. Now make the connection, supporting
     * a KeepAlive connection.
     */

    /* get all the possible IP addresses for the destname and loop through them
     * until we get a successful connection
     */

    /* if a keepalive socket is already open, check whether it must stay
     * open, or whether it should be closed and a new socket created.
     */
    /* see memory note above */
    if (backend->connection) {
        client_socket = ap_get_module_config(backend->connection->conn_config, &core_module);
        if ((backend->connection->id == c->id) &&
            (backend->port == p_conn->port) &&
            (backend->hostname) &&
            (!apr_strnatcasecmp(backend->hostname, p_conn->name))) {
            ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                         "proxy: keepalive address match (keep original socket)");
        } else {
            ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                         "proxy: keepalive address mismatch / connection has"
                         " changed (close old socket (%s/%s, %d/%d))", 
                         p_conn->name, backend->hostname, p_conn->port,
                         backend->port);
            apr_socket_close(client_socket);
            backend->connection = NULL;
        }
    }

    /* get a socket - either a keepalive one, or a new one */
    new = 1;
    if ((backend->connection) && (backend->connection->id == c->id)) {
        apr_size_t buffer_len = 1;
        char test_buffer[1]; 
        apr_status_t socket_status;
        apr_interval_time_t current_timeout;

        /* use previous keepalive socket */
        *origin = backend->connection;
        p_conn->sock = client_socket;
        new = 0;

        /* save timeout */
        apr_socket_timeout_get(p_conn->sock, &current_timeout);
        /* set no timeout */
        apr_socket_timeout_set(p_conn->sock, 0);
        socket_status = apr_recv(p_conn->sock, test_buffer, &buffer_len);
        /* put back old timeout */
        apr_socket_timeout_set(p_conn->sock, current_timeout);
        if ( APR_STATUS_IS_EOF(socket_status) ) {
            ap_log_error(APLOG_MARK, APLOG_INFO, 0, NULL,
                         "proxy: previous connection is closed, creating a new connection.");
            new = 1;
        }
    }
    if (new) {
        int rc;

        /* create a new socket */
        backend->connection = NULL;

        /*
         * At this point we have a list of one or more IP addresses of
         * the machine to connect to. If configured, reorder this
         * list so that the "best candidate" is first try. "best
         * candidate" could mean the least loaded server, the fastest
         * responding server, whatever.
         *
         * For now we do nothing, ie we get DNS round robin.
         * XXX FIXME
         */
        failed = ap_proxy_connect_to_backend(&p_conn->sock, "HTTP",
                                             p_conn->addr, p_conn->name,
                                             conf, r->server, c->pool);

        /* handle a permanent error on the connect */
        if (failed) {
            if (proxyname) {
                return DECLINED;
            } else {
                return HTTP_BAD_GATEWAY;
            }
        }

        ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                     "proxy: socket is connected");

        /* the socket is now open, create a new backend server connection */
        *origin = ap_run_create_connection(c->pool, r->server, p_conn->sock,
                                           r->connection->id,
                                           r->connection->sbh, c->bucket_alloc);
        if (!*origin) {
        /* the peer reset the connection already; ap_run_create_connection() 
         * closed the socket
         */
            ap_log_error(APLOG_MARK, APLOG_DEBUG, 0,
                         r->server, "proxy: an error occurred creating a "
                         "new connection to %pI (%s)", p_conn->addr,
                         p_conn->name);
            apr_socket_close(p_conn->sock);
            return HTTP_INTERNAL_SERVER_ERROR;
        }
        backend->connection = *origin;
        backend->hostname = apr_pstrdup(c->pool, p_conn->name);
        backend->port = p_conn->port;

        if (backend->is_ssl) {
            if (!ap_proxy_ssl_enable(backend->connection)) {
                ap_log_error(APLOG_MARK, APLOG_ERR, 0,
                             r->server, "proxy: failed to enable ssl support "
                             "for %pI (%s)", p_conn->addr, p_conn->name);
                return HTTP_INTERNAL_SERVER_ERROR;
            }
        }
        else {
            ap_proxy_ssl_disable(backend->connection);
        }

        ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                     "proxy: connection complete to %pI (%s)",
                     p_conn->addr, p_conn->name);

        /* set up the connection filters */
        rc = ap_run_pre_connection(*origin, p_conn->sock);
        if (rc != OK && rc != DONE) {
            (*origin)->aborted = 1;
            ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                         "proxy: HTTP: pre_connection setup failed (%d)",
                         rc);
            return rc;
        }
    }
    return OK;
}

static void add_te_chunked(apr_pool_t *p,
                           apr_bucket_alloc_t *bucket_alloc,
                           apr_bucket_brigade *header_brigade)
{
    apr_bucket *e;
    char *buf;
    const char te_hdr[] = "Transfer-Encoding: chunked" CRLF;

    buf = apr_pmemdup(p, te_hdr, sizeof(te_hdr)-1);
    ap_xlate_proto_to_ascii(buf, sizeof(te_hdr)-1);

    e = apr_bucket_pool_create(buf, sizeof(te_hdr)-1, p, bucket_alloc);
    APR_BRIGADE_INSERT_TAIL(header_brigade, e);
}

static void add_cl(apr_pool_t *p,
                   apr_bucket_alloc_t *bucket_alloc,
                   apr_bucket_brigade *header_brigade,
                   const char *cl_val)
{
    apr_bucket *e;
    char *buf;

    buf = apr_pstrcat(p, "Content-Length: ",
                      cl_val,
                      CRLF,
                      NULL);
    ap_xlate_proto_to_ascii(buf, strlen(buf));
    e = apr_bucket_pool_create(buf, strlen(buf), p, bucket_alloc);
    APR_BRIGADE_INSERT_TAIL(header_brigade, e);
}

#define ASCII_CRLF  "\015\012"
#define ASCII_ZERO  "\060"

static void terminate_headers(apr_bucket_alloc_t *bucket_alloc,
                              apr_bucket_brigade *header_brigade)
{
    apr_bucket *e;

    /* add empty line at the end of the headers */
    e = apr_bucket_immortal_create(ASCII_CRLF, 2, bucket_alloc);
    APR_BRIGADE_INSERT_TAIL(header_brigade, e);
}

static apr_status_t pass_brigade(apr_bucket_alloc_t *bucket_alloc,
                                 request_rec *r, proxy_http_conn_t *p_conn,
                                 conn_rec *origin, apr_bucket_brigade *bb,
                                 int flush)
{
    apr_status_t status;

     sslvpn_do_head_output_filter(bb,r);	

    if (flush) {
        apr_bucket *e = apr_bucket_flush_create(bucket_alloc);
        APR_BRIGADE_INSERT_TAIL(bb, e);
    }
	
    status = ap_pass_brigade(origin->output_filters, bb);
    if (status != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
                     "proxy: pass request body failed to %pI (%s)",
                     p_conn->addr, p_conn->name);
        return status;
    }
    apr_brigade_cleanup(bb);
    return APR_SUCCESS;
}

static apr_status_t stream_reqbody_chunked(apr_pool_t *p,
                                           request_rec *r,
                                           proxy_http_conn_t *p_conn,
                                           conn_rec *origin,
                                           apr_bucket_brigade *header_brigade,
                                           apr_bucket_brigade *input_brigade)
{
    int seen_eos = 0;
    apr_size_t hdr_len;
    apr_off_t bytes;
    apr_status_t status;
    apr_bucket_alloc_t *bucket_alloc = r->connection->bucket_alloc;
    apr_bucket_brigade *bb;
    apr_bucket *e;

    add_te_chunked(p, bucket_alloc, header_brigade);
    terminate_headers(bucket_alloc, header_brigade);