proc.c

Apache 2.0.63 is the current stable version of the 2.0 series, and is recommended over any previous

 * from failing to inherit our standard handles.
 */
apr_status_t apr_threadproc_init(apr_pool_t *pool)
{
    IF_WIN_OS_IS_UNICODE
    {
        InitializeCriticalSection(&proc_lock);
        /* register the cleanup */
        apr_pool_cleanup_register(pool, &proc_lock,
                                  threadproc_global_cleanup,
                                  apr_pool_cleanup_null);
    }
    return APR_SUCCESS;
}

#else /* !APR_HAS_UNICODE_FS || defined(_WIN32_WCE) */

apr_status_t apr_threadproc_init(apr_pool_t *pool)
{
    return APR_SUCCESS;
}

#endif

APR_DECLARE(apr_status_t) apr_proc_create(apr_proc_t *new,
                                          const char *progname,
                                          const char * const *args,
                                          const char * const *env,
                                          apr_procattr_t *attr,
                                          apr_pool_t *pool)
{
    apr_status_t rv;
    apr_size_t i;
    const char *argv0;
    char *cmdline;
    char *pEnvBlock;
    PROCESS_INFORMATION pi;
    DWORD dwCreationFlags = 0;

    new->in = attr->parent_in;
    new->out = attr->parent_out;
    new->err = attr->parent_err;

    if (attr->detached) {
        /* If we are creating ourselves detached, Then we should hide the
         * window we are starting in.  And we had better redfine our
         * handles for STDIN, STDOUT, and STDERR. Do not set the
         * detached attribute for Win9x. We have found that Win9x does
         * not manage the stdio handles properly when running old 16
         * bit executables if the detached attribute is set.
         */
        if (apr_os_level >= APR_WIN_NT) {
            /* 
             * XXX DETACHED_PROCESS won't on Win9x at all; on NT/W2K 
             * 16 bit executables fail (MS KB: Q150956)
             */
            dwCreationFlags |= DETACHED_PROCESS;
        }
    }

    /* progname must be unquoted, in native format, as there are all sorts 
     * of bugs in the NT library loader code that fault when parsing '/'.
     * XXX progname must be NULL if this is a 16 bit app running in WOW
     */
    if (progname[0] == '\"') {
        progname = apr_pstrndup(pool, progname + 1, strlen(progname) - 2);
    }

    if (attr->cmdtype == APR_PROGRAM || attr->cmdtype == APR_PROGRAM_ENV) {
        char *fullpath = NULL;
        if ((rv = apr_filepath_merge(&fullpath, attr->currdir, progname, 
                                     APR_FILEPATH_NATIVE, pool)) != APR_SUCCESS) {
            if (attr->errfn) {
                attr->errfn(pool, rv, 
                            apr_pstrcat(pool, "filepath_merge failed.", 
                                        " currdir: ", attr->currdir, 
                                        " progname: ", progname,NULL));
            }
            return rv;
        }
        progname = fullpath;
    } 
    else {
        /* Do not fail if the path isn't parseable for APR_PROGRAM_PATH
         * or APR_SHELLCMD.  We only invoke apr_filepath_merge (with no
         * left hand side expression) in order to correct the path slash
         * delimiters.  But the filename doesn't need to be in the CWD,
         * nor does it need to be a filename at all (it could be a
         * built-in shell command.)
         */
        char *fullpath = NULL;
        if ((rv = apr_filepath_merge(&fullpath, "", progname, 
                                     APR_FILEPATH_NATIVE, pool)) == APR_SUCCESS) {
            progname = fullpath;
        }        
    }

    if (has_space(progname)) {
        argv0 = apr_pstrcat(pool, "\"", progname, "\"", NULL);
    }
    else {
        argv0 = progname;
    }

    /* Handle the args, seperate from argv0 */
    cmdline = "";
    for (i = 1; args && args[i]; ++i) {
        if (has_space(args[i]) || !args[i][0]) {
            cmdline = apr_pstrcat(pool, cmdline, " \"", args[i], "\"", NULL);
        }
        else {
            cmdline = apr_pstrcat(pool, cmdline, " ", args[i], NULL);
        }
    }

#ifndef _WIN32_WCE
    if (attr->cmdtype == APR_SHELLCMD || attr->cmdtype == APR_SHELLCMD_ENV) {
        char *shellcmd = getenv("COMSPEC");
        if (!shellcmd) {
            if (attr->errfn) {
                attr->errfn(pool, APR_EINVAL, "COMSPEC envar is not set");
            }
            return APR_EINVAL;
        }
        if (shellcmd[0] == '"') {
            progname = apr_pstrndup(pool, shellcmd + 1, strlen(shellcmd) - 2);
        }
        else {
            progname = shellcmd;
            if (has_space(shellcmd)) {
                shellcmd = apr_pstrcat(pool, "\"", shellcmd, "\"", NULL);
            }
        }
        /* Command.com does not support a quoted command, while cmd.exe demands one.
         */
        i = strlen(progname);
        if (i >= 11 && strcasecmp(progname + i - 11, "command.com") == 0) {
            cmdline = apr_pstrcat(pool, shellcmd, " /C ", argv0, cmdline, NULL);
        }
        else {
            cmdline = apr_pstrcat(pool, shellcmd, " /C \"", argv0, cmdline, "\"", NULL);
        }
    } 
    else 
#endif
    {
#if defined(_WIN32_WCE)
        {
#else
        /* Win32 is _different_ than unix.  While unix will find the given
         * program since it's already chdir'ed, Win32 cannot since the parent
         * attempts to open the program with it's own path.
         * ###: This solution isn't much better - it may defeat path searching
         * when the path search was desired.  Open to further discussion.
         */
        i = strlen(progname);
        if (i >= 4 && (strcasecmp(progname + i - 4, ".bat") == 0
                    || strcasecmp(progname + i - 4, ".cmd") == 0))
        {
            char *shellcmd = getenv("COMSPEC");
            if (!shellcmd) {
                if (attr->errfn) {
                    attr->errfn(pool, APR_EINVAL, "COMSPEC envar is not set");
                }
                return APR_EINVAL;
            }
            if (shellcmd[0] == '"') {
                progname = apr_pstrndup(pool, shellcmd + 1, strlen(shellcmd) - 2);
            }
            else {
                progname = shellcmd;
                if (has_space(shellcmd)) {
                    shellcmd = apr_pstrcat(pool, "\"", shellcmd, "\"", NULL);
                }
            }
            i = strlen(progname);
            if (i >= 11 && strcasecmp(progname + i - 11, "command.com") == 0) {
                /* XXX: Still insecure - need doubled-quotes on each individual
                 * arg of cmdline.  Suspect we need to postpone cmdline parsing
                 * until this moment in all four code paths, with some flags
                 * to toggle 'which flavor' is needed.
                 */
                cmdline = apr_pstrcat(pool, shellcmd, " /C ", argv0, cmdline, NULL);
            }
            else {
                /* We must protect the cmdline args from any interpolation - this
                 * is not a shellcmd, and the source of argv[] is untrusted.
                 * Notice we escape ALL the cmdline args, including the quotes
                 * around the individual args themselves.  No sense in allowing
                 * the shift-state to be toggled, and the application will 
                 * not see the caret escapes.
                 */
                cmdline = apr_caret_escape_args(pool, cmdline);
                /*
                 * Our app name must always be quoted so the quotes surrounding
                 * the entire /c "command args" are unambigious.
                 */
                if (*argv0 != '"') {
                    cmdline = apr_pstrcat(pool, shellcmd, " /C \"\"", argv0, "\"", cmdline, "\"", NULL);
                }
                else {
                    cmdline = apr_pstrcat(pool, shellcmd, " /C \"", argv0, cmdline, "\"", NULL);
                }
            }
        }
        else {
#endif
            /* A simple command we are directly invoking.  Do not pass
             * the first arg to CreateProc() for APR_PROGRAM_PATH
             * invocation, since it would need to be a literal and
             * complete file path.  That is; "c:\bin\aprtest.exe"
             * would succeed, but "c:\bin\aprtest" or "aprtest.exe"
             * can fail.
             */
            cmdline = apr_pstrcat(pool, argv0, cmdline, NULL);

            if (attr->cmdtype == APR_PROGRAM_PATH) {
                progname = NULL;
            }
        }
    }

    if (!env || attr->cmdtype == APR_PROGRAM_ENV ||
        attr->cmdtype == APR_SHELLCMD_ENV) {
        pEnvBlock = NULL;
    }
    else {
        apr_size_t iEnvBlockLen;
        /*
         * Win32's CreateProcess call requires that the environment
         * be passed in an environment block, a null terminated block of
         * null terminated strings.
         */  
        i = 0;
        iEnvBlockLen = 1;
        while (env[i]) {
            iEnvBlockLen += strlen(env[i]) + 1;
            i++;
        }
        if (!i) 
            ++iEnvBlockLen;

#if APR_HAS_UNICODE_FS
        IF_WIN_OS_IS_UNICODE
        {
            apr_wchar_t *pNext;
            pEnvBlock = (char *)apr_palloc(pool, iEnvBlockLen * 2);
            dwCreationFlags |= CREATE_UNICODE_ENVIRONMENT;

            i = 0;
            pNext = (apr_wchar_t*)pEnvBlock;
            while (env[i]) {
                apr_size_t in = strlen(env[i]) + 1;
                if ((rv = apr_conv_utf8_to_ucs2(env[i], &in, 
                                                pNext, &iEnvBlockLen)) 
                        != APR_SUCCESS) {
                    if (attr->errfn) {
                        attr->errfn(pool, rv, 
                                    apr_pstrcat(pool, 
                                                "utf8 to ucs2 conversion failed" 
                                                " on this string: ", env[i], NULL));
                    }
                    return rv;
                }
                pNext = wcschr(pNext, L'\0') + 1;
                i++;
            }
	    if (!i)
                *(pNext++) = L'\0';
	    *pNext = L'\0';
        }
#endif /* APR_HAS_UNICODE_FS */
#if APR_HAS_ANSI_FS
        ELSE_WIN_OS_IS_ANSI
        {
            char *pNext;
            pEnvBlock = (char *)apr_palloc(pool, iEnvBlockLen);
    
            i = 0;
            pNext = pEnvBlock;
            while (env[i]) {
                strcpy(pNext, env[i]);
                pNext = strchr(pNext, '\0') + 1;
                i++;
            }
	    if (!i)
                *(pNext++) = '\0';
	    *pNext = '\0';
        }
#endif /* APR_HAS_ANSI_FS */
    }