view src/os/win32/ngx_service.c @ 7054:e02555553d0b

Range filter: protect from total size overflows. The overflow can be used to circumvent the restriction on total size of ranges introduced in c2a91088b0c0 (1.1.2). Additionally, overflow allows producing ranges with negative start (such ranges can be created by using a suffix, "bytes=-100"; normally this results in 200 due to the total size check). These can result in the following errors in logs: [crit] ... pread() ... failed (22: Invalid argument) [alert] ... sendfile() failed (22: Invalid argument) When using cache, it can be also used to reveal cache file header. It is believed that there are no other negative effects, at least with standard nginx modules. In theory, this can also result in memory disclosure and/or segmentation faults if multiple ranges are allowed, and the response is returned in a single in-memory buffer. This never happens with standard nginx modules though, as well as known 3rd party modules. Fix is to properly protect from possible overflow when incrementing size.
author Maxim Dounin <mdounin@mdounin.ru>
date Tue, 11 Jul 2017 16:06:23 +0300
parents a1caf3989b49
children
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */



#define NGX_SERVICE_CONTROL_SHUTDOWN   128
#define NGX_SERVICE_CONTROL_REOPEN     129


SERVICE_TABLE_ENTRY st[] = {
    { "nginx", service_main },
    { NULL, NULL }
};


ngx_int_t
ngx_service(ngx_log_t *log)
{
    /* primary thread */

    /* StartServiceCtrlDispatcher() should be called within 30 seconds */

    if (StartServiceCtrlDispatcher(st) == 0) {
        ngx_log_error(NGX_LOG_EMERG, log, ngx_errno,
                      "StartServiceCtrlDispatcher() failed");
        return NGX_ERROR;
    }

    return NGX_OK;
}


void
service_main(u_int argc, char **argv)
{
    SERVICE_STATUS         status;
    SERVICE_STATUS_HANDLE  service;

    /* thread spawned by SCM */

    service = RegisterServiceCtrlHandlerEx("nginx", service_handler, ctx);
    if (service == INVALID_HANDLE_VALUE) {
        ngx_log_error(NGX_LOG_EMERG, log, ngx_errno,
                      "RegisterServiceCtrlHandlerEx() failed");
        return;
    }

    status.dwServiceType = SERVICE_WIN32_OWN_PROCESS;
    status.dwCurrentState = SERVICE_START_PENDING;
    status.dwControlsAccepted = SERVICE_ACCEPT_STOP
                                |SERVICE_ACCEPT_PARAMCHANGE;
    status.dwWin32ExitCode = NO_ERROR;
    status.dwServiceSpecificExitCode = 0;
    status.dwCheckPoint = 1;
    status.dwWaitHint = 2000;

    /* SetServiceStatus() should be called within 80 seconds */

    if (SetServiceStatus(service, &status) == 0) {
        ngx_log_error(NGX_LOG_EMERG, log, ngx_errno,
                      "SetServiceStatus() failed");
        return;
    }

    /* init */

    status.dwCurrentState = SERVICE_RUNNING;
    status.dwCheckPoint = 0;
    status.dwWaitHint = 0;

    if (SetServiceStatus(service, &status) == 0) {
        ngx_log_error(NGX_LOG_EMERG, log, ngx_errno,
                      "SetServiceStatus() failed");
        return;
    }

    /* call master or worker loop */

    /*
     * master should use event notification and look status
     * single should use iocp to get notifications from service handler
     */

}


u_int
service_handler(u_int control, u_int type, void *data, void *ctx)
{
    /* primary thread */

    switch (control) {

    case SERVICE_CONTROL_INTERROGATE:
        status = NGX_IOCP_INTERROGATE;
        break;

    case SERVICE_CONTROL_STOP:
        status = NGX_IOCP_STOP;
        break;

    case SERVICE_CONTROL_PARAMCHANGE:
        status = NGX_IOCP_RECONFIGURE;
        break;

    case NGX_SERVICE_CONTROL_SHUTDOWN:
        status = NGX_IOCP_REOPEN;
        break;

    case NGX_SERVICE_CONTROL_REOPEN:
        status = NGX_IOCP_REOPEN;
        break;

    default:
        return ERROR_CALL_NOT_IMPLEMENTED;
    }

    if (ngx_single) {
        if (PostQueuedCompletionStatus(iocp, ... status, ...) == 0) {
            err = ngx_errno;
            ngx_log_error(NGX_LOG_ALERT, log, err,
                          "PostQueuedCompletionStatus() failed");
            return err;
        }

    } else {
        Event
    }

    return NO_ERROR;
}