diff options
Diffstat (limited to 'scripts/selinux/mdp/mdp.c')
-rw-r--r-- | scripts/selinux/mdp/mdp.c | 273 |
1 files changed, 273 insertions, 0 deletions
diff --git a/scripts/selinux/mdp/mdp.c b/scripts/selinux/mdp/mdp.c new file mode 100644 index 000000000..1415604c3 --- /dev/null +++ b/scripts/selinux/mdp/mdp.c @@ -0,0 +1,273 @@ +// 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> + */ + + +/* NOTE: we really do want to use the kernel headers here */ +#define __EXPORTED_HEADERS__ + +#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_REISERFS_FS_SECURITY + FS_USE("xattr", "reiserfs"); +#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; +} |