// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 * mdp - make dummy policy
 *
 * When pointed at a kernel tree, builds a dummy policy for that kernel
 * with exactly one type with full rights to itself.
 *
 * Copyright (C) IBM Corporation, 2006
 *
 * Authors: Serge E. Hallyn <serue@us.ibm.com>
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <linux/kconfig.h>

static void usage(char *name)
{
        printf("usage: %s [-m] policy_file context_file\n", name);
        exit(1);
}

/* Class/perm mapping support */
struct security_class_mapping {
        const char *name;
        const char *perms[sizeof(unsigned) * 8 + 1];
};

#include "classmap.h"
#include "initial_sid_to_string.h"
#include "policycap_names.h"

#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))

int main(int argc, char *argv[])
{
        int i, j, mls = 0;
        int initial_sid_to_string_len;
        char **arg, *polout, *ctxout;

        FILE *fout;

        if (argc < 3)
                usage(argv[0]);
        arg = argv+1;
        if (argc==4 && strcmp(argv[1], "-m") == 0) {
                mls = 1;
                arg++;
        }
        polout = *arg++;
        ctxout = *arg;

        fout = fopen(polout, "w");
        if (!fout) {
                printf("Could not open %s for writing\n", polout);
                usage(argv[0]);
        }

        /* print out the classes */
        for (i = 0; secclass_map[i].name; i++)
                fprintf(fout, "class %s\n", secclass_map[i].name);
        fprintf(fout, "\n");

        initial_sid_to_string_len = sizeof(initial_sid_to_string) / sizeof (char *);
        /* print out the sids */
        for (i = 1; i < initial_sid_to_string_len; i++) {
                const char *name = initial_sid_to_string[i];

                if (name)
                        fprintf(fout, "sid %s\n", name);
                else
                        fprintf(fout, "sid unused%d\n", i);
        }
        fprintf(fout, "\n");

        /* print out the class permissions */
        for (i = 0; secclass_map[i].name; i++) {
                const struct security_class_mapping *map = &secclass_map[i];
                fprintf(fout, "class %s\n", map->name);
                fprintf(fout, "{\n");
                for (j = 0; map->perms[j]; j++)
                        fprintf(fout, "\t%s\n", map->perms[j]);
                fprintf(fout, "}\n\n");
        }
        fprintf(fout, "\n");

        /* print out mls declarations and constraints */
        if (mls) {
                fprintf(fout, "sensitivity s0;\n");
                fprintf(fout, "sensitivity s1;\n");
                fprintf(fout, "dominance { s0 s1 }\n");
                fprintf(fout, "category c0;\n");
                fprintf(fout, "category c1;\n");
                fprintf(fout, "level s0:c0.c1;\n");
                fprintf(fout, "level s1:c0.c1;\n");
#define SYSTEMLOW "s0"
#define SYSTEMHIGH "s1:c0.c1"
                for (i = 0; secclass_map[i].name; i++) {
                        const struct security_class_mapping *map = &secclass_map[i];

                        fprintf(fout, "mlsconstrain %s {\n", map->name);
                        for (j = 0; map->perms[j]; j++)
                                fprintf(fout, "\t%s\n", map->perms[j]);
                        /*
                         * This requires all subjects and objects to be
                         * single-level (l2 eq h2), and that the subject
                         * level dominate the object level (h1 dom h2)
                         * in order to have any permissions to it.
                         */
                        fprintf(fout, "} (l2 eq h2 and h1 dom h2);\n\n");
                }
        }

        /* enable all policy capabilities */
        for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++)
                fprintf(fout, "policycap %s;\n", selinux_policycap_names[i]);

        /* types, roles, and allows */
        fprintf(fout, "type base_t;\n");
        fprintf(fout, "role base_r;\n");
        fprintf(fout, "role base_r types { base_t };\n");
        for (i = 0; secclass_map[i].name; i++)
                fprintf(fout, "allow base_t base_t:%s *;\n",
                        secclass_map[i].name);
        fprintf(fout, "user user_u roles { base_r }");
        if (mls)
                fprintf(fout, " level %s range %s - %s", SYSTEMLOW,
                        SYSTEMLOW, SYSTEMHIGH);
        fprintf(fout, ";\n");

#define SUBJUSERROLETYPE "user_u:base_r:base_t"
#define OBJUSERROLETYPE "user_u:object_r:base_t"

        /* default sids */
        for (i = 1; i < initial_sid_to_string_len; i++) {
                const char *name = initial_sid_to_string[i];

                if (name)
                        fprintf(fout, "sid %s ", name);
                else
                        fprintf(fout, "sid unused%d\n", i);
                fprintf(fout, SUBJUSERROLETYPE "%s\n",
                        mls ? ":" SYSTEMLOW : "");
        }
        fprintf(fout, "\n");

#define FS_USE(behavior, fstype)                            \
        fprintf(fout, "fs_use_%s %s " OBJUSERROLETYPE "%s;\n", \
                behavior, fstype, mls ? ":" SYSTEMLOW : "")

        /*
         * Filesystems whose inode labels can be fetched via getxattr.
         */
#ifdef CONFIG_EXT2_FS_SECURITY
        FS_USE("xattr", "ext2");
#endif
#ifdef CONFIG_EXT4_FS_SECURITY
#ifdef CONFIG_EXT4_USE_FOR_EXT2
        FS_USE("xattr", "ext2");
#endif
        FS_USE("xattr", "ext3");
        FS_USE("xattr", "ext4");
#endif
#ifdef CONFIG_JFS_SECURITY
        FS_USE("xattr", "jfs");
#endif
#ifdef CONFIG_JFFS2_FS_SECURITY
        FS_USE("xattr", "jffs2");
#endif
#ifdef CONFIG_XFS_FS
        FS_USE("xattr", "xfs");
#endif
#ifdef CONFIG_GFS2_FS
        FS_USE("xattr", "gfs2");
#endif
#ifdef CONFIG_BTRFS_FS
        FS_USE("xattr", "btrfs");
#endif
#ifdef CONFIG_F2FS_FS_SECURITY
        FS_USE("xattr", "f2fs");
#endif
#ifdef CONFIG_OCFS2_FS
        FS_USE("xattr", "ocsfs2");
#endif
#ifdef CONFIG_OVERLAY_FS
        FS_USE("xattr", "overlay");
#endif
#ifdef CONFIG_SQUASHFS_XATTR
        FS_USE("xattr", "squashfs");
#endif

        /*
         * Filesystems whose inodes are labeled from allocating task.
         */
        FS_USE("task", "pipefs");
        FS_USE("task", "sockfs");

        /*
         * Filesystems whose inode labels are computed from both
         * the allocating task and the superblock label.
         */
#ifdef CONFIG_UNIX98_PTYS
        FS_USE("trans", "devpts");
#endif
#ifdef CONFIG_HUGETLBFS
        FS_USE("trans", "hugetlbfs");
#endif
#ifdef CONFIG_TMPFS
        FS_USE("trans", "tmpfs");
#endif
#ifdef CONFIG_DEVTMPFS
        FS_USE("trans", "devtmpfs");
#endif
#ifdef CONFIG_POSIX_MQUEUE
        FS_USE("trans", "mqueue");
#endif

#define GENFSCON(fstype, prefix)                             \
        fprintf(fout, "genfscon %s %s " OBJUSERROLETYPE "%s\n", \
                fstype, prefix, mls ? ":" SYSTEMLOW : "")

        /*
         * Filesystems whose inodes are labeled from path prefix match
         * relative to the filesystem root.  Depending on the filesystem,
         * only a single label for all inodes may be supported.  Here
         * we list the filesystem types for which per-file labeling is
         * supported using genfscon; any other filesystem type can also
         * be added by only with a single entry for all of its inodes.
         */
#ifdef CONFIG_PROC_FS
        GENFSCON("proc", "/");
#endif
#ifdef CONFIG_SECURITY_SELINUX
        GENFSCON("selinuxfs", "/");
#endif
#ifdef CONFIG_SYSFS
        GENFSCON("sysfs", "/");
#endif
#ifdef CONFIG_DEBUG_FS
        GENFSCON("debugfs", "/");
#endif
#ifdef CONFIG_TRACING
        GENFSCON("tracefs", "/");
#endif
#ifdef CONFIG_PSTORE
        GENFSCON("pstore", "/");
#endif
        GENFSCON("cgroup", "/");
        GENFSCON("cgroup2", "/");

        fclose(fout);

        fout = fopen(ctxout, "w");
        if (!fout) {
                printf("Wrote policy, but cannot open %s for writing\n", ctxout);
                usage(argv[0]);
        }
        fprintf(fout, "/ " OBJUSERROLETYPE "%s\n", mls ? ":" SYSTEMLOW : "");
        fprintf(fout, "/.* " OBJUSERROLETYPE "%s\n", mls ? ":" SYSTEMLOW : "");
        fclose(fout);

        return 0;
}