[PATCH 2/8] busybox -- SELinux option support for coreutils: ver3

[Denis Vlasenko]

On Friday 23 February 2007 09:47, Yuichi Nakamura wrote:
> [2/8] busybox-coreutils-02-copy.v3.patch
>   - cp: -Z,-c option support. 
>       -c option: security context is preserved during file copy.
>   - mv 
>     In SELinux, it is recommended to preserve security context 
>     when file is moved. By this patch, file context is preserved 
>     during file move.
>   - install
>     When file is copied by install, security context of installed file 
>     becomes different from value configured in file_contexts file.
>     By this patch, security context is set according to file_contexts file.
>     -Z option: security context can be set during file copy.
> 
> Signed-off-by: Yuichi Nakamura <ynakam at hitachisoft.jp>

        FILEUTILS_MAKE_SOFTLINK = 0x40,
+#if ENABLE_SELINUX
+       FILEUTILS_PRESERVE_SECURITY_CONTEXT = 0x80,
+       FILEUTILS_SET_SECURITY_CONTEXT = 0x100
+#endif
 };
-#define FILEUTILS_CP_OPTSTR "pdRfils"

+#define FILEUTILS_CP_OPTSTR "pdRfils" USE_SELINUX("c\b")
+
 extern const char *applet_name;
...
        { "owner",               0, NULL, 'o' },
+#if ENABLE_SELINUX
+       { "context",             1, NULL, 'Z' },
+       { "preserve_context",    0, NULL, '\b'},
+       { "preserve-context",    0, NULL, '\b'},
+
+#endif
        { 0, 0, 0, 0 }

Hmmm... we typically use high ascii values for this kind
of "fake" option chars. Example in wget.c:

        static const struct option wget_long_options[] = {
...
                { "user-agent",       required_argument, NULL, 'U' },
                { "passive-ftp",      no_argument, NULL, 0xff },
                { "header",           required_argument, NULL, 0xfe },
                { 0, 0, 0, 0 }
        };
        applet_long_options = wget_long_options;
#endif
        opt_complementary = "-1" USE_FEATURE_WGET_LONG_OPTIONS(":\xfe::");
        opt = getopt32(argc, argv, "cqO:P:Y:U:",   ...);

Notice that in this example we avoid giving "strange" chars to getopt32
*at all*, preventing our applets from having "hidden" options a-la
"wget $'-\xff' ftp://kernel.org/".

Can you avoid passing '\b' to getopt32 in install etc?


+                       bb_error_msg("warning: ignoring --preserve-context. "
+                                        "The kernel is not SELinux-enabled.\n" );

bb_error_msg don't need trailing '\n'.
I already mentioned that in the previous round of review.


+#if ENABLE_SELINUX
+       if ((flags & FILEUTILS_PRESERVE_SECURITY_CONTEXT) && is_selinux_enabled() > 0){
+               security_context_t con;
+               if (lgetfilecon (source, &con) >= 0){
+                       if (setfscreatecon(con) < 0) {
+                               bb_perror_msg ("cannot set setfscreatecon %s", con);
+                               freecon(con);
+                               return -1;
+                       }
+               }else{
+                       if( errno == ENOTSUP || errno == ENODATA ) {
+                               setfscreatecon(NULL);
+                       } else {
+                               bb_perror_msg ("cannot  lgetfilecon %s", source);
+                               return -1;
+                       }
+               }
+       }
+#endif

Usage of whitespace is very different from the rest of busybox code here.

--
vda