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| -rw-r--r-- | gs/man/gs.1 | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/gs/man/gs.1 b/gs/man/gs.1 index 423abbcc3..9cb92c473 100644 --- a/gs/man/gs.1 +++ b/gs/man/gs.1 @@ -277,8 +277,7 @@ X Windows). This may be needed if the platform fonts look undesirably different from the scalable fonts. .TP .B \-dSAFER -Disables the "deletefile" and "renamefile" operators and the ability to -open files in any mode other than read-only. This strongly recommended for +Restricts file operations the script can perform. Strongly recommended for spoolers, conversion scripts or other sensitive environments where a badly written or malicious PostScript program code must be prevented from changing important files. @@ -294,6 +293,40 @@ Selects an alternate initial output device, as described above. .BI \-sOutputFile= filename Selects an alternate output file (or pipe) for the initial output device, as described above. +.SH "SAFER MODE" +.PP +The +.B \-dSAFER +option disables the "deletefile" and "renamefile" operators and prohibits +opening piped commands ("%pipe%\fIcmd\fR"). Only "%stdout" and "%stderr" can be +opened for writing. It also disables reading from files, except for "%stdin", +files given as a command line argument, and files contained in paths given by +LIBPATH and FONTPATH or specified by the system params /FontResourceDir and +/GenericResourceDir. +.PP +This mode also sets the .LockSafetyParams parameter of the initial output device +to protect against programs that attempt to write to files using the OutputFile +device parameter. Since the device parameters specified on the command line, +including OutputFile, are set prior to SAFER mode, use of "-sOutputFile=..." on +the command line is unrestricted. +.PP +SAFER mode prevents changing the /GenericResourceDir, /FontResourceDir, +/SystemParamsPassword, and /StartJobPassword. +.PP +While SAFER mode is not the default, it is the default for many wrapper jobs +and may be the default in a subsequent release of Ghostscript. Thus jobs or +programs that need to open files or set restricted parameters should pass the +.B \-dNOSAFER +command line option or its synonym +.BR \-dDELAYSAFER . +.PP +When running with +.B \-dNOSAFER +it is possible to perform a "save" followed by ".setsafe", execute a file or +procedure in SAFER mode, and then use "restore" to return to NOSAFER mode. In +order to prevent the save object from being restored by the foreign file or +procedure, the ".runandhide" operator should be used to hide the save object +from the restricted procedure. .SH FILES .PP The locations of many Ghostscript run-time files are compiled into the |