mod_cgid.c

linux网络服务器工具

    cgid_server_conf *conf = ap_get_module_config(s->module_config,
                                                  &cgid_module);

    conf->logname = ap_server_root_relative(cmd->pool, arg);

    if (!conf->logname) {
        return apr_pstrcat(cmd->pool, "Invalid ScriptLog path ",
                           arg, NULL);
    }
    return NULL;
}

static const char *set_scriptlog_length(cmd_parms *cmd, void *dummy, const char *arg)
{
    server_rec *s = cmd->server;
    cgid_server_conf *conf = ap_get_module_config(s->module_config,
                                                  &cgid_module);

    conf->logbytes = atol(arg);
    return NULL;
}

static const char *set_scriptlog_buffer(cmd_parms *cmd, void *dummy, const char *arg)
{
    server_rec *s = cmd->server;
    cgid_server_conf *conf = ap_get_module_config(s->module_config,
                                                  &cgid_module);

    conf->bufbytes = atoi(arg);
    return NULL;
}

static const char *set_script_socket(cmd_parms *cmd, void *dummy, const char *arg)
{
    const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
    if (err != NULL) {
        return err;
    }

    /* Make sure the pid is appended to the sockname */
    sockname = ap_append_pid(cmd->pool, arg, ".");
    sockname = ap_server_root_relative(cmd->pool, sockname);

    if (!sockname) {
        return apr_pstrcat(cmd->pool, "Invalid ScriptSock path",
                           arg, NULL);
    }

    return NULL;
}

static const command_rec cgid_cmds[] =
{
    AP_INIT_TAKE1("ScriptLog", set_scriptlog, NULL, RSRC_CONF,
                  "the name of a log for script debugging info"),
    AP_INIT_TAKE1("ScriptLogLength", set_scriptlog_length, NULL, RSRC_CONF,
                  "the maximum length (in bytes) of the script debug log"),
    AP_INIT_TAKE1("ScriptLogBuffer", set_scriptlog_buffer, NULL, RSRC_CONF,
                  "the maximum size (in bytes) to record of a POST request"),
    AP_INIT_TAKE1("ScriptSock", set_script_socket, NULL, RSRC_CONF,
                  "the name of the socket to use for communication with "
                  "the cgi daemon."),
    {NULL}
};

static int log_scripterror(request_rec *r, cgid_server_conf * conf, int ret,
                           apr_status_t rv, char *error)
{
    apr_file_t *f = NULL;
    struct stat finfo;
    char time_str[APR_CTIME_LEN];
    int log_flags = rv ? APLOG_ERR : APLOG_ERR;

    ap_log_rerror(APLOG_MARK, log_flags, rv, r,
                "%s: %s", error, r->filename);

    /* XXX Very expensive mainline case! Open, then getfileinfo! */
    if (!conf->logname ||
        ((stat(conf->logname, &finfo) == 0)
         && (finfo.st_size > conf->logbytes)) ||
         (apr_file_open(&f, conf->logname,
                  APR_APPEND|APR_WRITE|APR_CREATE, APR_OS_DEFAULT, r->pool) != APR_SUCCESS)) {
        return ret;
    }

    /* "%% [Wed Jun 19 10:53:21 1996] GET /cgid-bin/printenv HTTP/1.0" */
    apr_ctime(time_str, apr_time_now());
    apr_file_printf(f, "%%%% [%s] %s %s%s%s %s\n", time_str, r->method, r->uri,
            r->args ? "?" : "", r->args ? r->args : "", r->protocol);
    /* "%% 500 /usr/local/apache/cgid-bin */
    apr_file_printf(f, "%%%% %d %s\n", ret, r->filename);

    apr_file_printf(f, "%%error\n%s\n", error);

    apr_file_close(f);
    return ret;
}

static int log_script(request_rec *r, cgid_server_conf * conf, int ret,
                      char *dbuf, const char *sbuf, apr_bucket_brigade *bb,
                      apr_file_t *script_err)
{
    const apr_array_header_t *hdrs_arr = apr_table_elts(r->headers_in);
    const apr_table_entry_t *hdrs = (apr_table_entry_t *) hdrs_arr->elts;
    char argsbuffer[HUGE_STRING_LEN];
    apr_file_t *f = NULL;
    apr_bucket *e;
    const char *buf;
    apr_size_t len;
    apr_status_t rv;
    int first;
    int i;
    struct stat finfo;
    char time_str[APR_CTIME_LEN];

    /* XXX Very expensive mainline case! Open, then getfileinfo! */
    if (!conf->logname ||
        ((stat(conf->logname, &finfo) == 0)
         && (finfo.st_size > conf->logbytes)) ||
         (apr_file_open(&f, conf->logname,
                  APR_APPEND|APR_WRITE|APR_CREATE, APR_OS_DEFAULT, r->pool) != APR_SUCCESS)) {
        /* Soak up script output */
        discard_script_output(bb);
        if (script_err) {
            while (apr_file_gets(argsbuffer, HUGE_STRING_LEN,
                                 script_err) == APR_SUCCESS)
                continue;
        }
        return ret;
    }

    /* "%% [Wed Jun 19 10:53:21 1996] GET /cgid-bin/printenv HTTP/1.0" */
    apr_ctime(time_str, apr_time_now());
    apr_file_printf(f, "%%%% [%s] %s %s%s%s %s\n", time_str, r->method, r->uri,
            r->args ? "?" : "", r->args ? r->args : "", r->protocol);
    /* "%% 500 /usr/local/apache/cgid-bin" */
    apr_file_printf(f, "%%%% %d %s\n", ret, r->filename);

    apr_file_puts("%request\n", f);
    for (i = 0; i < hdrs_arr->nelts; ++i) {
        if (!hdrs[i].key)
            continue;
        apr_file_printf(f, "%s: %s\n", hdrs[i].key, hdrs[i].val);
    }
    if ((r->method_number == M_POST || r->method_number == M_PUT)
        && *dbuf) {
        apr_file_printf(f, "\n%s\n", dbuf);
    }

    apr_file_puts("%response\n", f);
    hdrs_arr = apr_table_elts(r->err_headers_out);
    hdrs = (const apr_table_entry_t *) hdrs_arr->elts;

    for (i = 0; i < hdrs_arr->nelts; ++i) {
        if (!hdrs[i].key)
            continue;
        apr_file_printf(f, "%s: %s\n", hdrs[i].key, hdrs[i].val);
    }

    if (sbuf && *sbuf)
        apr_file_printf(f, "%s\n", sbuf);

    first = 1;

    for (e = APR_BRIGADE_FIRST(bb);
         e != APR_BRIGADE_SENTINEL(bb);
         e = APR_BUCKET_NEXT(e))
    {
        if (APR_BUCKET_IS_EOS(e)) {
            break;
        }
        rv = apr_bucket_read(e, &buf, &len, APR_BLOCK_READ);
        if (rv != APR_SUCCESS || (len == 0)) {
            break;
        }
        if (first) {
            apr_file_puts("%stdout\n", f);
            first = 0;
        }
        apr_file_write(f, buf, &len);
        apr_file_puts("\n", f);
    }

    if (script_err) {
        if (apr_file_gets(argsbuffer, HUGE_STRING_LEN,
                          script_err) == APR_SUCCESS) {
            apr_file_puts("%stderr\n", f);
            apr_file_puts(argsbuffer, f);
            while (apr_file_gets(argsbuffer, HUGE_STRING_LEN,
                                 script_err) == APR_SUCCESS)
                apr_file_puts(argsbuffer, f);
            apr_file_puts("\n", f);
        }
    }

    if (script_err) {
        apr_file_close(script_err);
    }

    apr_file_close(f);
    return ret;
}

static apr_status_t close_unix_socket(void *thefd)
{
    int fd = (int)((long)thefd);

    return close(fd);
}

static int connect_to_daemon(int *sdptr, request_rec *r,
                             cgid_server_conf *conf)
{
    struct sockaddr_un unix_addr;
    int sd;
    int connect_tries;
    apr_interval_time_t sliding_timer;

    memset(&unix_addr, 0, sizeof(unix_addr));
    unix_addr.sun_family = AF_UNIX;
    apr_cpystrn(unix_addr.sun_path, sockname, sizeof unix_addr.sun_path);

    connect_tries = 0;
    sliding_timer = 100000; /* 100 milliseconds */
    while (1) {
        ++connect_tries;
        if ((sd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
            return log_scripterror(r, conf, HTTP_INTERNAL_SERVER_ERROR, errno,
                                   "unable to create socket to cgi daemon");
        }
        if (connect(sd, (struct sockaddr *)&unix_addr, sizeof(unix_addr)) < 0) {
            if (errno == ECONNREFUSED && connect_tries < DEFAULT_CONNECT_ATTEMPTS) {
                ap_log_rerror(APLOG_MARK, APLOG_DEBUG, errno, r,
                              "connect #%d to cgi daemon failed, sleeping before retry",
                              connect_tries);
                close(sd);
                apr_sleep(sliding_timer);
                if (sliding_timer < apr_time_from_sec(2)) {
                    sliding_timer *= 2;
                }
            }
            else {
                close(sd);
                return log_scripterror(r, conf, HTTP_SERVICE_UNAVAILABLE, errno,
                                       "unable to connect to cgi daemon after multiple tries");
            }
        }
        else {
            apr_pool_cleanup_register(r->pool, (void *)((long)sd),
                                      close_unix_socket, apr_pool_cleanup_null);
            break; /* we got connected! */
        }
        /* gotta try again, but make sure the cgid daemon is still around */
        if (kill(daemon_pid, 0) != 0) {
            return log_scripterror(r, conf, HTTP_SERVICE_UNAVAILABLE, errno,
                                   "cgid daemon is gone; is Apache terminating?");
        }
    }
    *sdptr = sd;
    return OK;
}

static void discard_script_output(apr_bucket_brigade *bb)
{
    apr_bucket *e;
    const char *buf;
    apr_size_t len;
    apr_status_t rv;

    for (e = APR_BRIGADE_FIRST(bb);
         e != APR_BRIGADE_SENTINEL(bb);
         e = APR_BUCKET_NEXT(e))
    {
        if (APR_BUCKET_IS_EOS(e)) {
            break;
        }
        rv = apr_bucket_read(e, &buf, &len, APR_BLOCK_READ);
        if (rv != APR_SUCCESS) {
            break;
        }
    }
}

/****************************************************************
 *
 * Actual cgid handling...
 */

struct cleanup_script_info {
    request_rec *r;
    unsigned long conn_id;
    cgid_server_conf *conf;
};

static apr_status_t dead_yet(pid_t pid, apr_interval_time_t max_wait)
{
    apr_interval_time_t interval = 10000; /* 10 ms */
    apr_interval_time_t total = 0;

    do {
#ifdef _AIX
        /* On AIX, for processes like mod_cgid's script children where
         * SIGCHLD is ignored, kill(pid,0) returns success for up to
         * one second after the script child exits, based on when a
         * daemon runs to clean up unnecessary process table entries.
         * getpgid() can report the proper info (-1/ESRCH) immediately.
         */
        if (getpgid(pid) < 0) {
#else
        if (kill(pid, 0) < 0) {
#endif
            return APR_SUCCESS;
        }
        apr_sleep(interval);
        total = total + interval;
        if (interval < 500000) {
            interval *= 2;
        }
    } while (total < max_wait);
    return APR_EGENERAL;
}

static apr_status_t cleanup_nonchild_process(request_rec *r, pid_t pid)
{
    kill(pid, SIGTERM); /* in case it isn't dead yet */
    if (dead_yet(pid, apr_time_from_sec(3)) == APR_SUCCESS) {
        return APR_SUCCESS;
    }
    ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                  "CGI process %" APR_PID_T_FMT " didn't exit, sending SIGKILL",
                  pid);
    kill(pid, SIGKILL);
    if (dead_yet(pid, apr_time_from_sec(3)) == APR_SUCCESS) {
        return APR_SUCCESS;
    }
    ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                  "CGI process %" APR_PID_T_FMT " didn't exit, sending SIGKILL again",
                  pid);
    kill(pid, SIGKILL);

    return APR_EGENERAL;
}

static apr_status_t cleanup_script(void *vptr)
{
    struct cleanup_script_info *info = vptr;
    int sd;
    int rc;
    cgid_req_t req = {0};
    pid_t pid;
    apr_status_t stat;

    rc = connect_to_daemon(&sd, info->r, info->conf);
    if (rc != OK) {
        return APR_EGENERAL;
    }

    /* we got a socket, and there is already a cleanup registered for it */

    req.req_type = GETPID_REQ;
    req.ppid = parent_pid;
    req.conn_id = info->r->connection->id;

    stat = sock_write(sd, &req, sizeof(req));
    if (stat != APR_SUCCESS) {
        return stat;
    }

    /* wait for pid of script */
    stat = sock_read(sd, &pid, sizeof(pid));
    if (stat != APR_SUCCESS) {
        return stat;
    }

    if (pid == 0) {
        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, info->r,
                      "daemon couldn't find CGI process for connection %lu",
                      info->conn_id);
        return APR_EGENERAL;
    }
    return cleanup_nonchild_process(info->r, pid);
}

static int cgid_handler(request_rec *r)
{
    conn_rec *c = r->connection;
    int retval, nph, dbpos = 0;
    char *argv0, *dbuf = NULL;
    apr_bucket_brigade *bb;
    apr_bucket *b;
    cgid_server_conf *conf;
    int is_included;
    int seen_eos, child_stopped_reading;
    int sd;
    char **env;
    apr_file_t *tempsock;
    struct cleanup_script_info *info;
    apr_status_t rv;

    if (strcmp(r->handler,CGI_MAGIC_TYPE) && strcmp(r->handler,"cgi-script"))
        return DECLINED;

    conf = ap_get_module_config(r->server->module_config, &cgid_module);
    is_included = !strcmp(r->protocol, "INCLUDED");

    if ((argv0 = strrchr(r->filename, '/')) != NULL)
        argv0++;
    else
        argv0 = r->filename;

    nph = !(strncmp(argv0, "nph-", 4));

    argv0 = r->filename;

    if (!(ap_allow_options(r) & OPT_EXECCGI) && !is_scriptaliased(r))
        return log_scripterror(r, conf, HTTP_FORBIDDEN, 0,
                               "Options ExecCGI is off in this directory");
    if (nph && is_included)
        return log_scripterror(r, conf, HTTP_FORBIDDEN, 0,
                               "attempt to include NPH CGI script");

#if defined(OS2) || defined(WIN32)
#error mod_cgid does not work on this platform.  If you teach it to, look
#error at mod_cgi.c for required code in this path.
#else
    if (r->finfo.filetype == 0)
        return log_scripterror(r, conf, HTTP_NOT_FOUND, 0,
                               "script not found or unable to stat");
#endif
    if (r->finfo.filetype == APR_DIR)
        return log_scripterror(r, conf, HTTP_FORBIDDEN, 0,
                               "attempt to invoke directory as script");

    if ((r->used_path_info == AP_REQ_REJECT_PATH_INFO) &&
        r->path_info && *r->path_info)
    {
        /* default to accept */
        return log_scripterror(r, conf, HTTP_NOT_FOUND, 0,
                               "AcceptPathInfo off disallows user's path");
    }
/*
    if (!ap_suexec_enabled) {
        if (!ap_can_exec(&r->finfo))
            return log_scripterror(r, conf, HTTP_FORBIDDEN, 0,
                                   "file permissions deny server execution");
    }
*/
    ap_add_common_vars(r);
    ap_add_cgi_vars(r);
    env = ap_create_environment(r->pool, r->subprocess_env);

    if ((retval = connect_to_daemon(&sd, r, conf)) != OK) {
        return retval;
    }

    rv = send_req(sd, r, argv0, env, CGI_REQ);
    if (rv != APR_SUCCESS) {