diff options
-rw-r--r-- | security/tomoyo/tomoyo.c | 293 | ||||
-rw-r--r-- | security/tomoyo/tomoyo.h | 106 |
2 files changed, 399 insertions, 0 deletions
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c new file mode 100644 index 000000000000..f3ab20758c0f --- /dev/null +++ b/security/tomoyo/tomoyo.c @@ -0,0 +1,293 @@ +/* + * security/tomoyo/tomoyo.c + * + * LSM hooks for TOMOYO Linux. + * + * Copyright (C) 2005-2009 NTT DATA CORPORATION + * + * Version: 2.2.0-pre 2009/02/01 + * + */ + +#include <linux/security.h> +#include "common.h" +#include "tomoyo.h" +#include "realpath.h" + +static int tomoyo_cred_prepare(struct cred *new, const struct cred *old, + gfp_t gfp) +{ + /* + * Since "struct tomoyo_domain_info *" is a sharable pointer, + * we don't need to duplicate. + */ + new->security = old->security; + return 0; +} + +static int tomoyo_bprm_set_creds(struct linux_binprm *bprm) +{ + /* + * Do only if this function is called for the first time of an execve + * operation. + */ + if (bprm->cred_prepared) + return 0; + /* + * Load policy if /sbin/tomoyo-init exists and /sbin/init is requested + * for the first time. + */ + if (!tomoyo_policy_loaded) + tomoyo_load_policy(bprm->filename); + /* + * Tell tomoyo_bprm_check_security() is called for the first time of an + * execve operation. + */ + bprm->cred->security = NULL; + return 0; +} + +static int tomoyo_bprm_check_security(struct linux_binprm *bprm) +{ + struct tomoyo_domain_info *domain = bprm->cred->security; + + /* + * Execute permission is checked against pathname passed to do_execve() + * using current domain. + */ + if (!domain) { + struct tomoyo_domain_info *next_domain = NULL; + int retval = tomoyo_find_next_domain(bprm, &next_domain); + + if (!retval) + bprm->cred->security = next_domain; + return retval; + } + /* + * Read permission is checked against interpreters using next domain. + * '1' is the result of open_to_namei_flags(O_RDONLY). + */ + return tomoyo_check_open_permission(domain, &bprm->file->f_path, 1); +} + +#ifdef CONFIG_SYSCTL + +static int tomoyo_prepend(char **buffer, int *buflen, const char *str) +{ + int namelen = strlen(str); + + if (*buflen < namelen) + return -ENOMEM; + *buflen -= namelen; + *buffer -= namelen; + memcpy(*buffer, str, namelen); + return 0; +} + +/** + * tomoyo_sysctl_path - return the realpath of a ctl_table. + * @table: pointer to "struct ctl_table". + * + * Returns realpath(3) of the @table on success. + * Returns NULL on failure. + * + * This function uses tomoyo_alloc(), so the caller must call tomoyo_free() + * if this function didn't return NULL. + */ +static char *tomoyo_sysctl_path(struct ctl_table *table) +{ + int buflen = TOMOYO_MAX_PATHNAME_LEN; + char *buf = tomoyo_alloc(buflen); + char *end = buf + buflen; + int error = -ENOMEM; + + if (!buf) + return NULL; + + *--end = '\0'; + buflen--; + while (table) { + char buf[32]; + const char *sp = table->procname; + + if (!sp) { + memset(buf, 0, sizeof(buf)); + snprintf(buf, sizeof(buf) - 1, "=%d=", table->ctl_name); + sp = buf; + } + if (tomoyo_prepend(&end, &buflen, sp) || + tomoyo_prepend(&end, &buflen, "/")) + goto out; + table = table->parent; + } + if (tomoyo_prepend(&end, &buflen, "/proc/sys")) + goto out; + error = tomoyo_encode(buf, end - buf, end); + out: + if (!error) + return buf; + tomoyo_free(buf); + return NULL; +} + +static int tomoyo_sysctl(struct ctl_table *table, int op) +{ + int error; + char *name; + + op &= MAY_READ | MAY_WRITE; + if (!op) + return 0; + name = tomoyo_sysctl_path(table); + if (!name) + return -ENOMEM; + error = tomoyo_check_file_perm(tomoyo_domain(), name, op); + tomoyo_free(name); + return error; +} +#endif + +static int tomoyo_path_truncate(struct path *path, loff_t length, + unsigned int time_attrs) +{ + return tomoyo_check_1path_perm(tomoyo_domain(), + TOMOYO_TYPE_TRUNCATE_ACL, + path); +} + +static int tomoyo_path_unlink(struct path *parent, struct dentry *dentry) +{ + struct path path = { parent->mnt, dentry }; + return tomoyo_check_1path_perm(tomoyo_domain(), + TOMOYO_TYPE_UNLINK_ACL, + &path); +} + +static int tomoyo_path_mkdir(struct path *parent, struct dentry *dentry, + int mode) +{ + struct path path = { parent->mnt, dentry }; + return tomoyo_check_1path_perm(tomoyo_domain(), + TOMOYO_TYPE_MKDIR_ACL, + &path); +} + +static int tomoyo_path_rmdir(struct path *parent, struct dentry *dentry) +{ + struct path path = { parent->mnt, dentry }; + return tomoyo_check_1path_perm(tomoyo_domain(), + TOMOYO_TYPE_RMDIR_ACL, + &path); +} + +static int tomoyo_path_symlink(struct path *parent, struct dentry *dentry, + const char *old_name) +{ + struct path path = { parent->mnt, dentry }; + return tomoyo_check_1path_perm(tomoyo_domain(), + TOMOYO_TYPE_SYMLINK_ACL, + &path); +} + +static int tomoyo_path_mknod(struct path *parent, struct dentry *dentry, + int mode, unsigned int dev) +{ + struct path path = { parent->mnt, dentry }; + int type = TOMOYO_TYPE_CREATE_ACL; + + switch (mode & S_IFMT) { + case S_IFCHR: + type = TOMOYO_TYPE_MKCHAR_ACL; + break; + case S_IFBLK: + type = TOMOYO_TYPE_MKBLOCK_ACL; + break; + case S_IFIFO: + type = TOMOYO_TYPE_MKFIFO_ACL; + break; + case S_IFSOCK: + type = TOMOYO_TYPE_MKSOCK_ACL; + break; + } + return tomoyo_check_1path_perm(tomoyo_domain(), + type, &path); +} + +static int tomoyo_path_link(struct dentry *old_dentry, struct path *new_dir, + struct dentry *new_dentry) +{ + struct path path1 = { new_dir->mnt, old_dentry }; + struct path path2 = { new_dir->mnt, new_dentry }; + return tomoyo_check_2path_perm(tomoyo_domain(), + TOMOYO_TYPE_LINK_ACL, + &path1, &path2); +} + +static int tomoyo_path_rename(struct path *old_parent, + struct dentry *old_dentry, + struct path *new_parent, + struct dentry *new_dentry) +{ + struct path path1 = { old_parent->mnt, old_dentry }; + struct path path2 = { new_parent->mnt, new_dentry }; + return tomoyo_check_2path_perm(tomoyo_domain(), + TOMOYO_TYPE_RENAME_ACL, + &path1, &path2); +} + +static int tomoyo_file_fcntl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + if (cmd == F_SETFL && ((arg ^ file->f_flags) & O_APPEND)) + return tomoyo_check_rewrite_permission(tomoyo_domain(), file); + return 0; +} + +static int tomoyo_dentry_open(struct file *f, const struct cred *cred) +{ + int flags = f->f_flags; + + if ((flags + 1) & O_ACCMODE) + flags++; + flags |= f->f_flags & (O_APPEND | O_TRUNC); + /* Don't check read permission here if called from do_execve(). */ + if (current->in_execve) + return 0; + return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags); +} + +static struct security_operations tomoyo_security_ops = { + .name = "tomoyo", + .cred_prepare = tomoyo_cred_prepare, + .bprm_set_creds = tomoyo_bprm_set_creds, + .bprm_check_security = tomoyo_bprm_check_security, +#ifdef CONFIG_SYSCTL + .sysctl = tomoyo_sysctl, +#endif + .file_fcntl = tomoyo_file_fcntl, + .dentry_open = tomoyo_dentry_open, + .path_truncate = tomoyo_path_truncate, + .path_unlink = tomoyo_path_unlink, + .path_mkdir = tomoyo_path_mkdir, + .path_rmdir = tomoyo_path_rmdir, + .path_symlink = tomoyo_path_symlink, + .path_mknod = tomoyo_path_mknod, + .path_link = tomoyo_path_link, + .path_rename = tomoyo_path_rename, +}; + +static int __init tomoyo_init(void) +{ + struct cred *cred = (struct cred *) current_cred(); + + if (!security_module_enable(&tomoyo_security_ops)) + return 0; + /* register ourselves with the security framework */ + if (register_security(&tomoyo_security_ops)) + panic("Failure registering TOMOYO Linux"); + printk(KERN_INFO "TOMOYO Linux initialized\n"); + cred->security = &tomoyo_kernel_domain; + return 0; +} + +security_initcall(tomoyo_init); diff --git a/security/tomoyo/tomoyo.h b/security/tomoyo/tomoyo.h new file mode 100644 index 000000000000..a0c8f6e0bea4 --- /dev/null +++ b/security/tomoyo/tomoyo.h @@ -0,0 +1,106 @@ +/* + * security/tomoyo/tomoyo.h + * + * Implementation of the Domain-Based Mandatory Access Control. + * + * Copyright (C) 2005-2009 NTT DATA CORPORATION + * + * Version: 2.2.0-pre 2009/02/01 + * + */ + +#ifndef _SECURITY_TOMOYO_TOMOYO_H +#define _SECURITY_TOMOYO_TOMOYO_H + +struct tomoyo_path_info; +struct path; +struct inode; +struct linux_binprm; +struct pt_regs; +struct tomoyo_page_buffer; + +int tomoyo_check_file_perm(struct tomoyo_domain_info *domain, + const char *filename, const u8 perm); +int tomoyo_check_exec_perm(struct tomoyo_domain_info *domain, + const struct tomoyo_path_info *filename, + struct tomoyo_page_buffer *buf); +int tomoyo_check_open_permission(struct tomoyo_domain_info *domain, + struct path *path, const int flag); +int tomoyo_check_1path_perm(struct tomoyo_domain_info *domain, + const u8 operation, struct path *path); +int tomoyo_check_2path_perm(struct tomoyo_domain_info *domain, + const u8 operation, struct path *path1, + struct path *path2); +int tomoyo_check_rewrite_permission(struct tomoyo_domain_info *domain, + struct file *filp); +int tomoyo_find_next_domain(struct linux_binprm *bprm, + struct tomoyo_domain_info **next_domain); + +/* Index numbers for Access Controls. */ + +#define TOMOYO_TYPE_SINGLE_PATH_ACL 0 +#define TOMOYO_TYPE_DOUBLE_PATH_ACL 1 + +/* Index numbers for File Controls. */ + +/* + * TYPE_READ_WRITE_ACL is special. TYPE_READ_WRITE_ACL is automatically set + * if both TYPE_READ_ACL and TYPE_WRITE_ACL are set. Both TYPE_READ_ACL and + * TYPE_WRITE_ACL are automatically set if TYPE_READ_WRITE_ACL is set. + * TYPE_READ_WRITE_ACL is automatically cleared if either TYPE_READ_ACL or + * TYPE_WRITE_ACL is cleared. Both TYPE_READ_ACL and TYPE_WRITE_ACL are + * automatically cleared if TYPE_READ_WRITE_ACL is cleared. + */ + +#define TOMOYO_TYPE_READ_WRITE_ACL 0 +#define TOMOYO_TYPE_EXECUTE_ACL 1 +#define TOMOYO_TYPE_READ_ACL 2 +#define TOMOYO_TYPE_WRITE_ACL 3 +#define TOMOYO_TYPE_CREATE_ACL 4 +#define TOMOYO_TYPE_UNLINK_ACL 5 +#define TOMOYO_TYPE_MKDIR_ACL 6 +#define TOMOYO_TYPE_RMDIR_ACL 7 +#define TOMOYO_TYPE_MKFIFO_ACL 8 +#define TOMOYO_TYPE_MKSOCK_ACL 9 +#define TOMOYO_TYPE_MKBLOCK_ACL 10 +#define TOMOYO_TYPE_MKCHAR_ACL 11 +#define TOMOYO_TYPE_TRUNCATE_ACL 12 +#define TOMOYO_TYPE_SYMLINK_ACL 13 +#define TOMOYO_TYPE_REWRITE_ACL 14 +#define TOMOYO_MAX_SINGLE_PATH_OPERATION 15 + +#define TOMOYO_TYPE_LINK_ACL 0 +#define TOMOYO_TYPE_RENAME_ACL 1 +#define TOMOYO_MAX_DOUBLE_PATH_OPERATION 2 + +#define TOMOYO_DOMAINPOLICY 0 +#define TOMOYO_EXCEPTIONPOLICY 1 +#define TOMOYO_DOMAIN_STATUS 2 +#define TOMOYO_PROCESS_STATUS 3 +#define TOMOYO_MEMINFO 4 +#define TOMOYO_SELFDOMAIN 5 +#define TOMOYO_VERSION 6 +#define TOMOYO_PROFILE 7 +#define TOMOYO_MANAGER 8 + +extern struct tomoyo_domain_info tomoyo_kernel_domain; + +static inline struct tomoyo_domain_info *tomoyo_domain(void) +{ + return current_cred()->security; +} + +/* Caller holds tasklist_lock spinlock. */ +static inline struct tomoyo_domain_info *tomoyo_real_domain(struct task_struct + *task) +{ + /***** CRITICAL SECTION START *****/ + const struct cred *cred = get_task_cred(task); + struct tomoyo_domain_info *domain = cred->security; + + put_cred(cred); + return domain; + /***** CRITICAL SECTION END *****/ +} + +#endif /* !defined(_SECURITY_TOMOYO_TOMOYO_H) */ |