Ylarod 898e9d4f8c
[1.0] Drop Non-GKI Support (#1483)
Co-authored-by: weishu <twsxtd@gmail.com>
2024-06-01 14:50:46 +08:00

464 lines
13 KiB
C

#include <linux/uaccess.h>
#include <linux/types.h>
#include <linux/version.h>
#include "../klog.h" // IWYU pragma: keep
#include "selinux.h"
#include "sepolicy.h"
#include "ss/services.h"
#include "linux/lsm_audit.h"
#include "xfrm.h"
#define SELINUX_POLICY_INSTEAD_SELINUX_SS
#define KERNEL_SU_DOMAIN "su"
#define KERNEL_SU_FILE "ksu_file"
#define KERNEL_EXEC_TYPE "ksu_exec"
#define ALL NULL
static struct policydb *get_policydb(void)
{
struct policydb *db;
struct selinux_policy *policy = rcu_dereference(selinux_state.policy);
db = &policy->policydb;
return db;
}
void apply_kernelsu_rules()
{
if (!getenforce()) {
pr_info("SELinux permissive or disabled, apply rules!\n");
}
rcu_read_lock();
struct policydb *db = get_policydb();
ksu_permissive(db, KERNEL_SU_DOMAIN);
ksu_typeattribute(db, KERNEL_SU_DOMAIN, "mlstrustedsubject");
ksu_typeattribute(db, KERNEL_SU_DOMAIN, "netdomain");
ksu_typeattribute(db, KERNEL_SU_DOMAIN, "bluetoothdomain");
// Create unconstrained file type
ksu_type(db, KERNEL_SU_FILE, "file_type");
ksu_typeattribute(db, KERNEL_SU_FILE, "mlstrustedobject");
ksu_allow(db, ALL, KERNEL_SU_FILE, ALL, ALL);
// allow all!
ksu_allow(db, KERNEL_SU_DOMAIN, ALL, ALL, ALL);
// allow us do any ioctl
if (db->policyvers >= POLICYDB_VERSION_XPERMS_IOCTL) {
ksu_allowxperm(db, KERNEL_SU_DOMAIN, ALL, "blk_file", ALL);
ksu_allowxperm(db, KERNEL_SU_DOMAIN, ALL, "fifo_file", ALL);
ksu_allowxperm(db, KERNEL_SU_DOMAIN, ALL, "chr_file", ALL);
ksu_allowxperm(db, KERNEL_SU_DOMAIN, ALL, "file", ALL);
}
// we need to save allowlist in /data/adb/ksu
ksu_allow(db, "kernel", "adb_data_file", "dir", ALL);
ksu_allow(db, "kernel", "adb_data_file", "file", ALL);
// we need to search /data/app
ksu_allow(db, "kernel", "apk_data_file", "file", "open");
ksu_allow(db, "kernel", "apk_data_file", "dir", "open");
ksu_allow(db, "kernel", "apk_data_file", "dir", "read");
ksu_allow(db, "kernel", "apk_data_file", "dir", "search");
// we may need to do mount on shell
ksu_allow(db, "kernel", "shell_data_file", "file", ALL);
// we need to read /data/system/packages.list
ksu_allow(db, "kernel", "kernel", "capability", "dac_override");
// Android 10+:
// http://aospxref.com/android-12.0.0_r3/xref/system/sepolicy/private/file_contexts#512
ksu_allow(db, "kernel", "packages_list_file", "file", ALL);
// Kernel 4.4
ksu_allow(db, "kernel", "packages_list_file", "dir", ALL);
// Android 9-:
// http://aospxref.com/android-9.0.0_r61/xref/system/sepolicy/private/file_contexts#360
ksu_allow(db, "kernel", "system_data_file", "file", ALL);
ksu_allow(db, "kernel", "system_data_file", "dir", ALL);
// our ksud triggered by init
ksu_allow(db, "init", "adb_data_file", "file", ALL);
ksu_allow(db, "init", "adb_data_file", "dir", ALL); // #1289
ksu_allow(db, "init", KERNEL_SU_DOMAIN, ALL, ALL);
// we need to umount modules in zygote
ksu_allow(db, "zygote", "adb_data_file", "dir", "search");
// copied from Magisk rules
// suRights
ksu_allow(db, "servicemanager", KERNEL_SU_DOMAIN, "dir", "search");
ksu_allow(db, "servicemanager", KERNEL_SU_DOMAIN, "dir", "read");
ksu_allow(db, "servicemanager", KERNEL_SU_DOMAIN, "file", "open");
ksu_allow(db, "servicemanager", KERNEL_SU_DOMAIN, "file", "read");
ksu_allow(db, "servicemanager", KERNEL_SU_DOMAIN, "process", "getattr");
ksu_allow(db, ALL, KERNEL_SU_DOMAIN, "process", "sigchld");
// allowLog
ksu_allow(db, "logd", KERNEL_SU_DOMAIN, "dir", "search");
ksu_allow(db, "logd", KERNEL_SU_DOMAIN, "file", "read");
ksu_allow(db, "logd", KERNEL_SU_DOMAIN, "file", "open");
ksu_allow(db, "logd", KERNEL_SU_DOMAIN, "file", "getattr");
// dumpsys
ksu_allow(db, ALL, KERNEL_SU_DOMAIN, "fd", "use");
ksu_allow(db, ALL, KERNEL_SU_DOMAIN, "fifo_file", "write");
ksu_allow(db, ALL, KERNEL_SU_DOMAIN, "fifo_file", "read");
ksu_allow(db, ALL, KERNEL_SU_DOMAIN, "fifo_file", "open");
ksu_allow(db, ALL, KERNEL_SU_DOMAIN, "fifo_file", "getattr");
// bootctl
ksu_allow(db, "hwservicemanager", KERNEL_SU_DOMAIN, "dir", "search");
ksu_allow(db, "hwservicemanager", KERNEL_SU_DOMAIN, "file", "read");
ksu_allow(db, "hwservicemanager", KERNEL_SU_DOMAIN, "file", "open");
ksu_allow(db, "hwservicemanager", KERNEL_SU_DOMAIN, "process",
"getattr");
// For mounting loop devices, mirrors, tmpfs
ksu_allow(db, "kernel", ALL, "file", "read");
ksu_allow(db, "kernel", ALL, "file", "write");
// Allow all binder transactions
ksu_allow(db, ALL, KERNEL_SU_DOMAIN, "binder", ALL);
// Allow system server kill su process
ksu_allow(db, "system_server", KERNEL_SU_DOMAIN, "process", "getpgid");
ksu_allow(db, "system_server", KERNEL_SU_DOMAIN, "process", "sigkill");
rcu_read_unlock();
}
#define MAX_SEPOL_LEN 128
#define CMD_NORMAL_PERM 1
#define CMD_XPERM 2
#define CMD_TYPE_STATE 3
#define CMD_TYPE 4
#define CMD_TYPE_ATTR 5
#define CMD_ATTR 6
#define CMD_TYPE_TRANSITION 7
#define CMD_TYPE_CHANGE 8
#define CMD_GENFSCON 9
struct sepol_data {
u32 cmd;
u32 subcmd;
char __user *sepol1;
char __user *sepol2;
char __user *sepol3;
char __user *sepol4;
char __user *sepol5;
char __user *sepol6;
char __user *sepol7;
};
static int get_object(char *buf, char __user *user_object, size_t buf_sz,
char **object)
{
if (!user_object) {
*object = ALL;
return 0;
}
if (strncpy_from_user(buf, user_object, buf_sz) < 0) {
return -1;
}
*object = buf;
return 0;
}
// reset avc cache table, otherwise the new rules will not take effect if already denied
static void reset_avc_cache()
{
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(6, 4, 0))
avc_ss_reset(0);
selnl_notify_policyload(0);
selinux_status_update_policyload(0);
#else
struct selinux_avc *avc = selinux_state.avc;
avc_ss_reset(avc, 0);
selnl_notify_policyload(0);
selinux_status_update_policyload(&selinux_state, 0);
#endif
selinux_xfrm_notify_policyload();
}
int handle_sepolicy(unsigned long arg3, void __user *arg4)
{
if (!arg4) {
return -1;
}
if (!getenforce()) {
pr_info("SELinux permissive or disabled when handle policy!\n");
}
struct sepol_data data;
if (copy_from_user(&data, arg4, sizeof(struct sepol_data))) {
pr_err("sepol: copy sepol_data failed.\n");
return -1;
}
u32 cmd = data.cmd;
u32 subcmd = data.subcmd;
rcu_read_lock();
struct policydb *db = get_policydb();
int ret = -1;
if (cmd == CMD_NORMAL_PERM) {
char src_buf[MAX_SEPOL_LEN];
char tgt_buf[MAX_SEPOL_LEN];
char cls_buf[MAX_SEPOL_LEN];
char perm_buf[MAX_SEPOL_LEN];
char *s, *t, *c, *p;
if (get_object(src_buf, data.sepol1, sizeof(src_buf), &s) < 0) {
pr_err("sepol: copy src failed.\n");
goto exit;
}
if (get_object(tgt_buf, data.sepol2, sizeof(tgt_buf), &t) < 0) {
pr_err("sepol: copy tgt failed.\n");
goto exit;
}
if (get_object(cls_buf, data.sepol3, sizeof(cls_buf), &c) < 0) {
pr_err("sepol: copy cls failed.\n");
goto exit;
}
if (get_object(perm_buf, data.sepol4, sizeof(perm_buf), &p) <
0) {
pr_err("sepol: copy perm failed.\n");
goto exit;
}
bool success = false;
if (subcmd == 1) {
success = ksu_allow(db, s, t, c, p);
} else if (subcmd == 2) {
success = ksu_deny(db, s, t, c, p);
} else if (subcmd == 3) {
success = ksu_auditallow(db, s, t, c, p);
} else if (subcmd == 4) {
success = ksu_dontaudit(db, s, t, c, p);
} else {
pr_err("sepol: unknown subcmd: %d\n", subcmd);
}
ret = success ? 0 : -1;
} else if (cmd == CMD_XPERM) {
char src_buf[MAX_SEPOL_LEN];
char tgt_buf[MAX_SEPOL_LEN];
char cls_buf[MAX_SEPOL_LEN];
char __maybe_unused
operation[MAX_SEPOL_LEN]; // it is always ioctl now!
char perm_set[MAX_SEPOL_LEN];
char *s, *t, *c;
if (get_object(src_buf, data.sepol1, sizeof(src_buf), &s) < 0) {
pr_err("sepol: copy src failed.\n");
goto exit;
}
if (get_object(tgt_buf, data.sepol2, sizeof(tgt_buf), &t) < 0) {
pr_err("sepol: copy tgt failed.\n");
goto exit;
}
if (get_object(cls_buf, data.sepol3, sizeof(cls_buf), &c) < 0) {
pr_err("sepol: copy cls failed.\n");
goto exit;
}
if (strncpy_from_user(operation, data.sepol4,
sizeof(operation)) < 0) {
pr_err("sepol: copy operation failed.\n");
goto exit;
}
if (strncpy_from_user(perm_set, data.sepol5, sizeof(perm_set)) <
0) {
pr_err("sepol: copy perm_set failed.\n");
goto exit;
}
bool success = false;
if (subcmd == 1) {
success = ksu_allowxperm(db, s, t, c, perm_set);
} else if (subcmd == 2) {
success = ksu_auditallowxperm(db, s, t, c, perm_set);
} else if (subcmd == 3) {
success = ksu_dontauditxperm(db, s, t, c, perm_set);
} else {
pr_err("sepol: unknown subcmd: %d\n", subcmd);
}
ret = success ? 0 : -1;
} else if (cmd == CMD_TYPE_STATE) {
char src[MAX_SEPOL_LEN];
if (strncpy_from_user(src, data.sepol1, sizeof(src)) < 0) {
pr_err("sepol: copy src failed.\n");
goto exit;
}
bool success = false;
if (subcmd == 1) {
success = ksu_permissive(db, src);
} else if (subcmd == 2) {
success = ksu_enforce(db, src);
} else {
pr_err("sepol: unknown subcmd: %d\n", subcmd);
}
if (success)
ret = 0;
} else if (cmd == CMD_TYPE || cmd == CMD_TYPE_ATTR) {
char type[MAX_SEPOL_LEN];
char attr[MAX_SEPOL_LEN];
if (strncpy_from_user(type, data.sepol1, sizeof(type)) < 0) {
pr_err("sepol: copy type failed.\n");
goto exit;
}
if (strncpy_from_user(attr, data.sepol2, sizeof(attr)) < 0) {
pr_err("sepol: copy attr failed.\n");
goto exit;
}
bool success = false;
if (cmd == CMD_TYPE) {
success = ksu_type(db, type, attr);
} else {
success = ksu_typeattribute(db, type, attr);
}
if (!success) {
pr_err("sepol: %d failed.\n", cmd);
goto exit;
}
ret = 0;
} else if (cmd == CMD_ATTR) {
char attr[MAX_SEPOL_LEN];
if (strncpy_from_user(attr, data.sepol1, sizeof(attr)) < 0) {
pr_err("sepol: copy attr failed.\n");
goto exit;
}
if (!ksu_attribute(db, attr)) {
pr_err("sepol: %d failed.\n", cmd);
goto exit;
}
ret = 0;
} else if (cmd == CMD_TYPE_TRANSITION) {
char src[MAX_SEPOL_LEN];
char tgt[MAX_SEPOL_LEN];
char cls[MAX_SEPOL_LEN];
char default_type[MAX_SEPOL_LEN];
char object[MAX_SEPOL_LEN];
if (strncpy_from_user(src, data.sepol1, sizeof(src)) < 0) {
pr_err("sepol: copy src failed.\n");
goto exit;
}
if (strncpy_from_user(tgt, data.sepol2, sizeof(tgt)) < 0) {
pr_err("sepol: copy tgt failed.\n");
goto exit;
}
if (strncpy_from_user(cls, data.sepol3, sizeof(cls)) < 0) {
pr_err("sepol: copy cls failed.\n");
goto exit;
}
if (strncpy_from_user(default_type, data.sepol4,
sizeof(default_type)) < 0) {
pr_err("sepol: copy default_type failed.\n");
goto exit;
}
char *real_object;
if (data.sepol5 == NULL) {
real_object = NULL;
} else {
if (strncpy_from_user(object, data.sepol5,
sizeof(object)) < 0) {
pr_err("sepol: copy object failed.\n");
goto exit;
}
real_object = object;
}
bool success = ksu_type_transition(db, src, tgt, cls,
default_type, real_object);
if (success)
ret = 0;
} else if (cmd == CMD_TYPE_CHANGE) {
char src[MAX_SEPOL_LEN];
char tgt[MAX_SEPOL_LEN];
char cls[MAX_SEPOL_LEN];
char default_type[MAX_SEPOL_LEN];
if (strncpy_from_user(src, data.sepol1, sizeof(src)) < 0) {
pr_err("sepol: copy src failed.\n");
goto exit;
}
if (strncpy_from_user(tgt, data.sepol2, sizeof(tgt)) < 0) {
pr_err("sepol: copy tgt failed.\n");
goto exit;
}
if (strncpy_from_user(cls, data.sepol3, sizeof(cls)) < 0) {
pr_err("sepol: copy cls failed.\n");
goto exit;
}
if (strncpy_from_user(default_type, data.sepol4,
sizeof(default_type)) < 0) {
pr_err("sepol: copy default_type failed.\n");
goto exit;
}
bool success = false;
if (subcmd == 1) {
success = ksu_type_change(db, src, tgt, cls,
default_type);
} else if (subcmd == 2) {
success = ksu_type_member(db, src, tgt, cls,
default_type);
} else {
pr_err("sepol: unknown subcmd: %d\n", subcmd);
}
if (success)
ret = 0;
} else if (cmd == CMD_GENFSCON) {
char name[MAX_SEPOL_LEN];
char path[MAX_SEPOL_LEN];
char context[MAX_SEPOL_LEN];
if (strncpy_from_user(name, data.sepol1, sizeof(name)) < 0) {
pr_err("sepol: copy name failed.\n");
goto exit;
}
if (strncpy_from_user(path, data.sepol2, sizeof(path)) < 0) {
pr_err("sepol: copy path failed.\n");
goto exit;
}
if (strncpy_from_user(context, data.sepol3, sizeof(context)) <
0) {
pr_err("sepol: copy context failed.\n");
goto exit;
}
if (!ksu_genfscon(db, name, path, context)) {
pr_err("sepol: %d failed.\n", cmd);
goto exit;
}
ret = 0;
} else {
pr_err("sepol: unknown cmd: %d\n", cmd);
}
exit:
rcu_read_unlock();
// only allow and xallow needs to reset avc cache, but we cannot do that because
// we are in atomic context. so we just reset it every time.
reset_avc_cache();
return ret;
}