lkml.org 
[lkml]   [2008]   [Nov]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[TOMOYO #13 (mmotm 2008-11-19-02-19) 08/11] Domain transition handler.
    This file controls domain creation/deletion/transition.

    Every process belongs to a domain in TOMOYO Linux.
    Domain transition occurs when execve(2) is called
    and the domain is expressed as 'process invocation history',
    such as '<kernel> /sbin/init /etc/init.d/rc'.
    Domain information is stored in current->cred->security field.

    Signed-off-by: Kentaro Takeda <takedakn@nttdata.co.jp>
    Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
    Signed-off-by: Toshiharu Harada <haradats@nttdata.co.jp>
    ---
    security/tomoyo/domain.c | 874 +++++++++++++++++++++++++++++++++++++++++++++++
    1 file changed, 874 insertions(+)

    --- /dev/null
    +++ linux-2.6.28-rc5-mm1/security/tomoyo/domain.c
    @@ -0,0 +1,874 @@
    +/*
    + * security/tomoyo/domain.c
    + *
    + * Implementation of the Domain-Based Mandatory Access Control.
    + *
    + * Copyright (C) 2005-2008 NTT DATA CORPORATION
    + *
    + * Version: 2.2.0-pre 2008/11/11
    + *
    + */
    +
    +#include "common.h"
    +#include "tomoyo.h"
    +#include "realpath.h"
    +#include <linux/binfmts.h>
    +
    +/* Variables definitions.*/
    +
    +/* The initial domain. */
    +struct tomoyo_domain_info tomoyo_kernel_domain;
    +
    +/*
    + * The list for "struct tomoyo_domain_info".
    + *
    + * The tomoyo_domain_list_lock mutex protects the tomoyo_domain_list list.
    + */
    +LIST1_HEAD(tomoyo_domain_list);
    +static DEFINE_MUTEX(tomoyo_domain_list_lock);
    +
    +/* Structure for "initialize_domain" and "no_initialize_domain" keyword. */
    +struct tomoyo_domain_initializer_entry {
    + struct list1_head list;
    + const struct tomoyo_path_info *domainname; /* This may be NULL */
    + const struct tomoyo_path_info *program;
    + bool is_deleted;
    + bool is_not; /* True if this entry is "no_initialize_domain". */
    + /* True if the domainname is tomoyo_get_last_name(). */
    + bool is_last_name;
    +};
    +
    +/* Structure for "keep_domain" and "no_keep_domain" keyword. */
    +struct tomoyo_domain_keeper_entry {
    + struct list1_head list;
    + const struct tomoyo_path_info *domainname;
    + const struct tomoyo_path_info *program; /* This may be NULL */
    + bool is_deleted;
    + bool is_not; /* True if this entry is "no_keep_domain". */
    + /* True if the domainname is tomoyo_get_last_name(). */
    + bool is_last_name;
    +};
    +
    +/* Structure for "alias" keyword. */
    +struct tomoyo_alias_entry {
    + struct list1_head list;
    + const struct tomoyo_path_info *original_name;
    + const struct tomoyo_path_info *aliased_name;
    + bool is_deleted;
    +};
    +
    +/**
    + * tomoyo_set_domain_flag - Set or clear domain's attribute flags.
    + *
    + * @domain: Pointer to "struct tomoyo_domain_info".
    + * @is_delete: True if it is a delete request.
    + * @flags: Flags to set or clear.
    + *
    + * Returns nothing.
    + */
    +void tomoyo_set_domain_flag(struct tomoyo_domain_info *domain,
    + const bool is_delete, const u8 flags)
    +{
    + /* We need to serialize because this is bitfield operation. */
    + static DEFINE_SPINLOCK(lock);
    + /***** CRITICAL SECTION START *****/
    + spin_lock(&lock);
    + if (!is_delete)
    + domain->flags |= flags;
    + else
    + domain->flags &= ~flags;
    + spin_unlock(&lock);
    + /***** CRITICAL SECTION END *****/
    +}
    +
    +/**
    + * tomoyo_get_last_name - Get last component of a domainname.
    + *
    + * @domain: Pointer to "struct tomoyo_domain_info".
    + *
    + * Returns the last component of the domainname.
    + */
    +const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain)
    +{
    + const char *cp0 = domain->domainname->name;
    + const char *cp1 = strrchr(cp0, ' ');
    +
    + if (cp1)
    + return cp1 + 1;
    + return cp0;
    +}
    +
    +/*
    + * The list for "struct tomoyo_domain_initializer_entry".
    + *
    + * This list is updated only inside
    + * tomoyo_update_domain_initializer_entry(),
    + * thus no global mutex exists.
    + */
    +static LIST1_HEAD(tomoyo_domain_initializer_list);
    +
    +/**
    + * tomoyo_update_domain_initializer_entry - Update "struct tomoyo_domain_initializer_entry" list.
    + *
    + * @domainname: The name of domain. May be NULL.
    + * @program: The name of program.
    + * @is_not: True if it is "no_initialize_domain" entry.
    + * @is_delete: True if it is a delete request.
    + *
    + * Returns 0 on success, negative value otherwise.
    + */
    +static int tomoyo_update_domain_initializer_entry(const char *domainname,
    + const char *program,
    + const bool is_not,
    + const bool is_delete)
    +{
    + struct tomoyo_domain_initializer_entry *new_entry;
    + struct tomoyo_domain_initializer_entry *ptr;
    + static DEFINE_MUTEX(lock);
    + const struct tomoyo_path_info *saved_program;
    + const struct tomoyo_path_info *saved_domainname = NULL;
    + int error = -ENOMEM;
    + bool is_last_name = false;
    +
    + if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__))
    + return -EINVAL; /* No patterns allowed. */
    + if (domainname) {
    + if (!tomoyo_is_domain_def(domainname) &&
    + tomoyo_is_correct_path(domainname, 1, -1, -1, __func__))
    + is_last_name = true;
    + else if (!tomoyo_is_correct_domain(domainname, __func__))
    + return -EINVAL;
    + saved_domainname = tomoyo_save_name(domainname);
    + if (!saved_domainname)
    + return -ENOMEM;
    + }
    + saved_program = tomoyo_save_name(program);
    + if (!saved_program)
    + return -ENOMEM;
    + /***** EXCLUSIVE SECTION START *****/
    + mutex_lock(&lock);
    + list1_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) {
    + if (ptr->is_not != is_not ||
    + ptr->domainname != saved_domainname ||
    + ptr->program != saved_program)
    + continue;
    + ptr->is_deleted = is_delete;
    + error = 0;
    + goto out;
    + }
    + if (is_delete) {
    + error = -ENOENT;
    + goto out;
    + }
    + new_entry = tomoyo_alloc_element(sizeof(*new_entry));
    + if (!new_entry)
    + goto out;
    + new_entry->domainname = saved_domainname;
    + new_entry->program = saved_program;
    + new_entry->is_not = is_not;
    + new_entry->is_last_name = is_last_name;
    + list1_add_tail(&new_entry->list, &tomoyo_domain_initializer_list);
    + error = 0;
    + out:
    + mutex_unlock(&lock);
    + /***** EXCLUSIVE SECTION END *****/
    + return error;
    +}
    +
    +/**
    + * tomoyo_read_domain_initializer_policy - Read "struct tomoyo_domain_initializer_entry" list.
    + *
    + * @head: Pointer to "struct tomoyo_io_buffer".
    + *
    + * Returns true on success, false otherwise.
    + */
    +bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head)
    +{
    + struct list1_head *pos;
    +
    + list1_for_each_cookie(pos, head->read_var2,
    + &tomoyo_domain_initializer_list) {
    + const char *no;
    + const char *from = "";
    + const char *domain = "";
    + struct tomoyo_domain_initializer_entry *ptr;
    + ptr = list1_entry(pos, struct tomoyo_domain_initializer_entry,
    + list);
    + if (ptr->is_deleted)
    + continue;
    + no = ptr->is_not ? "no_" : "";
    + if (ptr->domainname) {
    + from = " from ";
    + domain = ptr->domainname->name;
    + }
    + if (!tomoyo_io_printf(head,
    + "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN
    + "%s%s%s\n", no, ptr->program->name, from,
    + domain))
    + goto out;
    + }
    + return true;
    + out:
    + return false;
    +}
    +
    +/**
    + * tomoyo_write_domain_initializer_policy - Write "struct tomoyo_domain_initializer_entry" list.
    + *
    + * @data: String to parse.
    + * @is_not: True if it is "no_initialize_domain" entry.
    + * @is_delete: True if it is a delete request.
    + *
    + * Returns 0 on success, negative value otherwise.
    + */
    +int tomoyo_write_domain_initializer_policy(char *data, const bool is_not,
    + const bool is_delete)
    +{
    + char *cp = strstr(data, " from ");
    +
    + if (cp) {
    + *cp = '\0';
    + return tomoyo_update_domain_initializer_entry(cp + 6, data,
    + is_not,
    + is_delete);
    + }
    + return tomoyo_update_domain_initializer_entry(NULL, data, is_not,
    + is_delete);
    +}
    +
    +/**
    + * is_domain_initializer - Check whether the given program causes domainname reinitialization.
    + *
    + * @domainname: The name of domain.
    + * @program: The name of program.
    + * @last_name: The last component of @domainname.
    + *
    + * Returns true if executing @program reinitializes domain transition,
    + * false otherwise.
    + */
    +static bool is_domain_initializer(const struct tomoyo_path_info *domainname,
    + const struct tomoyo_path_info *program,
    + const struct tomoyo_path_info *last_name)
    +{
    + struct tomoyo_domain_initializer_entry *ptr;
    + bool flag = false;
    +
    + list1_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) {
    + if (ptr->is_deleted)
    + continue;
    + if (ptr->domainname) {
    + if (!ptr->is_last_name) {
    + if (ptr->domainname != domainname)
    + continue;
    + } else {
    + if (tomoyo_pathcmp(ptr->domainname, last_name))
    + continue;
    + }
    + }
    + if (tomoyo_pathcmp(ptr->program, program))
    + continue;
    + if (ptr->is_not)
    + return false;
    + flag = true;
    + }
    + return flag;
    +}
    +
    +/*
    + * The list for "struct tomoyo_domain_keeper_entry".
    + *
    + * This list is updated only inside tomoyo_update_domain_keeper_entry(),
    + * thus no global mutex exists.
    + */
    +static LIST1_HEAD(tomoyo_domain_keeper_list);
    +
    +/**
    + * tomoyo_update_domain_keeper_entry - Update "struct tomoyo_domain_keeper_entry" list.
    + *
    + * @domainname: The name of domain.
    + * @program: The name of program. May be NULL.
    + * @is_not: True if it is "no_keep_domain" entry.
    + * @is_delete: True if it is a delete request.
    + *
    + * Returns 0 on success, negative value otherwise.
    + */
    +static int tomoyo_update_domain_keeper_entry(const char *domainname,
    + const char *program,
    + const bool is_not,
    + const bool is_delete)
    +{
    + struct tomoyo_domain_keeper_entry *new_entry;
    + struct tomoyo_domain_keeper_entry *ptr;
    + const struct tomoyo_path_info *saved_domainname;
    + const struct tomoyo_path_info *saved_program = NULL;
    + static DEFINE_MUTEX(lock);
    + int error = -ENOMEM;
    + bool is_last_name = false;
    +
    + if (!tomoyo_is_domain_def(domainname) &&
    + tomoyo_is_correct_path(domainname, 1, -1, -1, __func__))
    + is_last_name = true;
    + else if (!tomoyo_is_correct_domain(domainname, __func__))
    + return -EINVAL;
    + if (program) {
    + if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__))
    + return -EINVAL;
    + saved_program = tomoyo_save_name(program);
    + if (!saved_program)
    + return -ENOMEM;
    + }
    + saved_domainname = tomoyo_save_name(domainname);
    + if (!saved_domainname)
    + return -ENOMEM;
    + /***** EXCLUSIVE SECTION START *****/
    + mutex_lock(&lock);
    + list1_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
    + if (ptr->is_not != is_not ||
    + ptr->domainname != saved_domainname ||
    + ptr->program != saved_program)
    + continue;
    + ptr->is_deleted = is_delete;
    + error = 0;
    + goto out;
    + }
    + if (is_delete) {
    + error = -ENOENT;
    + goto out;
    + }
    + new_entry = tomoyo_alloc_element(sizeof(*new_entry));
    + if (!new_entry)
    + goto out;
    + new_entry->domainname = saved_domainname;
    + new_entry->program = saved_program;
    + new_entry->is_not = is_not;
    + new_entry->is_last_name = is_last_name;
    + list1_add_tail(&new_entry->list, &tomoyo_domain_keeper_list);
    + error = 0;
    + out:
    + mutex_unlock(&lock);
    + /***** EXCLUSIVE SECTION END *****/
    + return error;
    +}
    +
    +/**
    + * tomoyo_write_domain_keeper_policy - Write "struct tomoyo_domain_keeper_entry" list.
    + *
    + * @data: String to parse.
    + * @is_not: True if it is "no_keep_domain" entry.
    + * @is_delete: True if it is a delete request.
    + *
    + */
    +int tomoyo_write_domain_keeper_policy(char *data, const bool is_not,
    + const bool is_delete)
    +{
    + char *cp = strstr(data, " from ");
    +
    + if (cp) {
    + *cp = '\0';
    + return tomoyo_update_domain_keeper_entry(cp + 6, data, is_not,
    + is_delete);
    + }
    + return tomoyo_update_domain_keeper_entry(data, NULL, is_not, is_delete);
    +}
    +
    +/**
    + * tomoyo_read_domain_keeper_policy - Read "struct tomoyo_domain_keeper_entry" list.
    + *
    + * @head: Pointer to "struct tomoyo_io_buffer".
    + *
    + * Returns true on success, false otherwise.
    + */
    +bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head)
    +{
    + struct list1_head *pos;
    +
    + list1_for_each_cookie(pos, head->read_var2,
    + &tomoyo_domain_keeper_list) {
    + struct tomoyo_domain_keeper_entry *ptr;
    + const char *no;
    + const char *from = "";
    + const char *program = "";
    +
    + ptr = list1_entry(pos, struct tomoyo_domain_keeper_entry, list);
    + if (ptr->is_deleted)
    + continue;
    + no = ptr->is_not ? "no_" : "";
    + if (ptr->program) {
    + from = " from ";
    + program = ptr->program->name;
    + }
    + if (!tomoyo_io_printf(head,
    + "%s" TOMOYO_KEYWORD_KEEP_DOMAIN
    + "%s%s%s\n", no, program, from,
    + ptr->domainname->name))
    + goto out;
    + }
    + return true;
    + out:
    + return false;
    +}
    +
    +/**
    + * is_domain_keeper - Check whether the given program causes domain transition suppression.
    + *
    + * @domainname: The name of domain.
    + * @program: The name of program.
    + * @last_name: The last component of @domainname.
    + *
    + * Returns true if executing @program supresses domain transition,
    + * false otherwise.
    + */
    +static bool is_domain_keeper(const struct tomoyo_path_info *domainname,
    + const struct tomoyo_path_info *program,
    + const struct tomoyo_path_info *last_name)
    +{
    + struct tomoyo_domain_keeper_entry *ptr;
    + bool flag = false;
    +
    + list1_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
    + if (ptr->is_deleted)
    + continue;
    + if (!ptr->is_last_name) {
    + if (ptr->domainname != domainname)
    + continue;
    + } else {
    + if (tomoyo_pathcmp(ptr->domainname, last_name))
    + continue;
    + }
    + if (ptr->program && tomoyo_pathcmp(ptr->program, program))
    + continue;
    + if (ptr->is_not)
    + return false;
    + flag = true;
    + }
    + return flag;
    +}
    +
    +/*
    + * The list for "struct tomoyo_alias_entry".
    + *
    + * This list is updated only inside tomoyo_update_alias_entry(), thus
    + * no global mutex exists.
    + */
    +static LIST1_HEAD(tomoyo_alias_list);
    +
    +/**
    + * tomoyo_update_alias_entry - Update "struct tomoyo_alias_entry" list.
    + *
    + * @original_name: The original program's real name.
    + * @aliased_name: The symbolic program's symbolic link's name.
    + * @is_delete: True if it is a delete request.
    + *
    + * Returns 0 on success, negative value otherwise.
    + */
    +static int tomoyo_update_alias_entry(const char *original_name,
    + const char *aliased_name,
    + const bool is_delete)
    +{
    + struct tomoyo_alias_entry *new_entry;
    + struct tomoyo_alias_entry *ptr;
    + static DEFINE_MUTEX(lock);
    + const struct tomoyo_path_info *saved_original_name;
    + const struct tomoyo_path_info *saved_aliased_name;
    + int error = -ENOMEM;
    +
    + if (!tomoyo_is_correct_path(original_name, 1, -1, -1, __func__) ||
    + !tomoyo_is_correct_path(aliased_name, 1, -1, -1, __func__))
    + return -EINVAL; /* No patterns allowed. */
    + saved_original_name = tomoyo_save_name(original_name);
    + saved_aliased_name = tomoyo_save_name(aliased_name);
    + if (!saved_original_name || !saved_aliased_name)
    + return -ENOMEM;
    + /***** EXCLUSIVE SECTION START *****/
    + mutex_lock(&lock);
    + list1_for_each_entry(ptr, &tomoyo_alias_list, list) {
    + if (ptr->original_name != saved_original_name ||
    + ptr->aliased_name != saved_aliased_name)
    + continue;
    + ptr->is_deleted = is_delete;
    + error = 0;
    + goto out;
    + }
    + if (is_delete) {
    + error = -ENOENT;
    + goto out;
    + }
    + new_entry = tomoyo_alloc_element(sizeof(*new_entry));
    + if (!new_entry)
    + goto out;
    + new_entry->original_name = saved_original_name;
    + new_entry->aliased_name = saved_aliased_name;
    + list1_add_tail(&new_entry->list, &tomoyo_alias_list);
    + error = 0;
    + out:
    + mutex_unlock(&lock);
    + /***** EXCLUSIVE SECTION END *****/
    + return error;
    +}
    +
    +/**
    + * tomoyo_read_alias_policy - Read "struct tomoyo_alias_entry" list.
    + *
    + * @head: Pointer to "struct tomoyo_io_buffer".
    + *
    + * Returns true on success, false otherwise.
    + */
    +bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head)
    +{
    + struct list1_head *pos;
    +
    + list1_for_each_cookie(pos, head->read_var2, &tomoyo_alias_list) {
    + struct tomoyo_alias_entry *ptr;
    +
    + ptr = list1_entry(pos, struct tomoyo_alias_entry, list);
    + if (ptr->is_deleted)
    + continue;
    + if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n",
    + ptr->original_name->name,
    + ptr->aliased_name->name))
    + goto out;
    + }
    + return true;
    + out:
    + return false;
    +}
    +
    +/**
    + * tomoyo_write_alias_policy - Write "struct tomoyo_alias_entry" list.
    + *
    + * @data: String to parse.
    + * @is_delete: True if it is a delete request.
    + *
    + * Returns 0 on success, negative value otherwise.
    + */
    +int tomoyo_write_alias_policy(char *data, const bool is_delete)
    +{
    + char *cp = strchr(data, ' ');
    +
    + if (!cp)
    + return -EINVAL;
    + *cp++ = '\0';
    + return tomoyo_update_alias_entry(data, cp, is_delete);
    +}
    +
    +/* Domain create/delete/undelete handler. */
    +
    +/* #define TOMOYO_DEBUG_DOMAIN_UNDELETE */
    +
    +/**
    + * tomoyo_delete_domain - Delete a domain.
    + *
    + * @domainname: The name of domain.
    + *
    + * Returns 0.
    + */
    +int tomoyo_delete_domain(char *domainname)
    +{
    + struct tomoyo_domain_info *domain;
    + struct tomoyo_path_info name;
    +
    + name.name = domainname;
    + tomoyo_fill_path_info(&name);
    + /***** EXCLUSIVE SECTION START *****/
    + mutex_lock(&tomoyo_domain_list_lock);
    +#ifdef TOMOYO_DEBUG_DOMAIN_UNDELETE
    + printk(KERN_DEBUG "tomoyo_delete_domain %s\n", domainname);
    + list1_for_each_entry(domain, &tomoyo_domain_list, list) {
    + if (tomoyo_pathcmp(domain->domainname, &name))
    + continue;
    + printk(KERN_DEBUG "List: %p %u\n", domain, domain->is_deleted);
    + }
    +#endif
    + /* Is there an active domain? */
    + list1_for_each_entry(domain, &tomoyo_domain_list, list) {
    + struct tomoyo_domain_info *domain2;
    + /* Never delete tomoyo_kernel_domain */
    + if (domain == &tomoyo_kernel_domain)
    + continue;
    + if (domain->is_deleted ||
    + tomoyo_pathcmp(domain->domainname, &name))
    + continue;
    + /* Mark already deleted domains as non undeletable. */
    + list1_for_each_entry(domain2, &tomoyo_domain_list, list) {
    + if (!domain2->is_deleted ||
    + tomoyo_pathcmp(domain2->domainname, &name))
    + continue;
    +#ifdef TOMOYO_DEBUG_DOMAIN_UNDELETE
    + if (domain2->is_deleted != 255)
    + printk(KERN_DEBUG
    + "Marked %p as non undeletable\n",
    + domain2);
    +#endif
    + domain2->is_deleted = 255;
    + }
    + /* Delete and mark active domain as undeletable. */
    + domain->is_deleted = 1;
    +#ifdef TOMOYO_DEBUG_DOMAIN_UNDELETE
    + printk(KERN_DEBUG "Marked %p as undeletable\n", domain);
    +#endif
    + break;
    + }
    + mutex_unlock(&tomoyo_domain_list_lock);
    + /***** EXCLUSIVE SECTION END *****/
    + return 0;
    +}
    +
    +/**
    + * tomoyo_undelete_domain - Undelete a domain.
    + *
    + * @domainname: The name of domain.
    + *
    + * Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise.
    + */
    +struct tomoyo_domain_info *tomoyo_undelete_domain(const char *domainname)
    +{
    + struct tomoyo_domain_info *domain;
    + struct tomoyo_domain_info *candidate_domain = NULL;
    + struct tomoyo_path_info name;
    +
    + name.name = domainname;
    + tomoyo_fill_path_info(&name);
    + /***** EXCLUSIVE SECTION START *****/
    + mutex_lock(&tomoyo_domain_list_lock);
    +#ifdef TOMOYO_DEBUG_DOMAIN_UNDELETE
    + printk(KERN_DEBUG "tomoyo_undelete_domain %s\n", domainname);
    + list1_for_each_entry(domain, &tomoyo_domain_list, list) {
    + if (tomoyo_pathcmp(domain->domainname, &name))
    + continue;
    + printk(KERN_DEBUG "List: %p %u\n", domain, domain->is_deleted);
    + }
    +#endif
    + list1_for_each_entry(domain, &tomoyo_domain_list, list) {
    + if (tomoyo_pathcmp(&name, domain->domainname))
    + continue;
    + if (!domain->is_deleted) {
    + /* This domain is active. I can't undelete. */
    + candidate_domain = NULL;
    +#ifdef TOMOYO_DEBUG_DOMAIN_UNDELETE
    + printk(KERN_DEBUG "%p is active. I can't undelete.\n",
    + domain);
    +#endif
    + break;
    + }
    + /* Is this domain undeletable? */
    + if (domain->is_deleted == 1)
    + candidate_domain = domain;
    + }
    + if (candidate_domain) {
    + candidate_domain->is_deleted = 0;
    +#ifdef TOMOYO_DEBUG_DOMAIN_UNDELETE
    + printk(KERN_DEBUG "%p was undeleted.\n", candidate_domain);
    +#endif
    + }
    + mutex_unlock(&tomoyo_domain_list_lock);
    + /***** EXCLUSIVE SECTION END *****/
    + return candidate_domain;
    +}
    +
    +/**
    + * tomoyo_find_or_assign_new_domain - Create a domain.
    + *
    + * @domainname: The name of domain.
    + * @profile: Profile number to assign if the domain was newly created.
    + *
    + * Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise.
    + */
    +struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
    + domainname,
    + const u8 profile)
    +{
    + struct tomoyo_domain_info *domain = NULL;
    + const struct tomoyo_path_info *saved_domainname;
    +
    + /***** EXCLUSIVE SECTION START *****/
    + mutex_lock(&tomoyo_domain_list_lock);
    + domain = tomoyo_find_domain(domainname);
    + if (domain)
    + goto out;
    + if (!tomoyo_is_correct_domain(domainname, __func__))
    + goto out;
    + saved_domainname = tomoyo_save_name(domainname);
    + if (!saved_domainname)
    + goto out;
    + /* Can I reuse memory of deleted domain? */
    + list1_for_each_entry(domain, &tomoyo_domain_list, list) {
    + struct task_struct *p;
    + struct tomoyo_acl_info *ptr;
    + bool flag;
    + if (!domain->is_deleted ||
    + domain->domainname != saved_domainname)
    + continue;
    + flag = false;
    + /***** CRITICAL SECTION START *****/
    + read_lock(&tasklist_lock);
    + for_each_process(p) {
    + if (tomoyo_real_domain(p) != domain)
    + continue;
    + flag = true;
    + break;
    + }
    + read_unlock(&tasklist_lock);
    + /***** CRITICAL SECTION END *****/
    + if (flag)
    + continue;
    +#ifdef TOMOYO_DEBUG_DOMAIN_UNDELETE
    + printk(KERN_DEBUG "Reusing %p %s\n", domain,
    + domain->domainname->name);
    +#endif
    + list1_for_each_entry(ptr, &domain->acl_info_list, list) {
    + ptr->type |= TOMOYO_ACL_DELETED;
    + }
    + tomoyo_set_domain_flag(domain, true, domain->flags);
    + domain->profile = profile;
    + domain->quota_warned = false;
    + mb(); /* Avoid out-of-order execution. */
    + domain->is_deleted = 0;
    + goto out;
    + }
    + /* No memory reusable. Create using new memory. */
    + domain = tomoyo_alloc_element(sizeof(*domain));
    + if (domain) {
    + INIT_LIST1_HEAD(&domain->acl_info_list);
    + domain->domainname = saved_domainname;
    + domain->profile = profile;
    + list1_add_tail(&domain->list, &tomoyo_domain_list);
    + }
    + out:
    + mutex_unlock(&tomoyo_domain_list_lock);
    + /***** EXCLUSIVE SECTION END *****/
    + return domain;
    +}
    +
    +/**
    + * tomoyo_find_next_domain - Find a domain.
    + *
    + * @bprm: Pointer to "struct linux_binprm".
    + * @next_domain: Pointer to pointer to "struct tomoyo_domain_info".
    + *
    + * Returns 0 on success, negative value otherwise.
    + */
    +int tomoyo_find_next_domain(struct linux_binprm *bprm,
    + struct tomoyo_domain_info **next_domain)
    +{
    + /*
    + * This function assumes that the size of buffer returned by
    + * tomoyo_realpath() = TOMOYO_MAX_PATHNAME_LEN.
    + */
    + struct tomoyo_page_buffer *tmp = tomoyo_alloc(sizeof(*tmp));
    + struct tomoyo_domain_info *old_domain = tomoyo_domain();
    + struct tomoyo_domain_info *domain = NULL;
    + const char *old_domain_name = old_domain->domainname->name;
    + const char *original_name = bprm->filename;
    + char *new_domain_name = NULL;
    + char *real_program_name = NULL;
    + char *symlink_program_name = NULL;
    + const u8 mode = tomoyo_check_flags(old_domain, TOMOYO_MAC_FOR_FILE);
    + const bool is_enforce = (mode == 3);
    + int retval = -ENOMEM;
    + struct tomoyo_path_info r; /* real name */
    + struct tomoyo_path_info s; /* symlink name */
    + struct tomoyo_path_info l; /* last name */
    + static bool initialized;
    +
    + if (!tmp)
    + goto out;
    +
    + if (!initialized) {
    + /*
    + * Built-in initializers. This is needed because policies are
    + * not loaded until starting /sbin/init.
    + */
    + tomoyo_update_domain_initializer_entry(NULL, "/sbin/hotplug",
    + false, false);
    + tomoyo_update_domain_initializer_entry(NULL, "/sbin/modprobe",
    + false, false);
    + initialized = true;
    + }
    +
    + /* Get tomoyo_realpath of program. */
    + retval = -ENOENT;
    + /* I hope tomoyo_realpath() won't fail with -ENOMEM. */
    + real_program_name = tomoyo_realpath(original_name);
    + if (!real_program_name)
    + goto out;
    + /* Get tomoyo_realpath of symbolic link. */
    + symlink_program_name = tomoyo_realpath_nofollow(original_name);
    + if (!symlink_program_name)
    + goto out;
    +
    + r.name = real_program_name;
    + tomoyo_fill_path_info(&r);
    + s.name = symlink_program_name;
    + tomoyo_fill_path_info(&s);
    + l.name = tomoyo_get_last_name(old_domain);
    + tomoyo_fill_path_info(&l);
    +
    + /* Check 'alias' directive. */
    + if (tomoyo_pathcmp(&r, &s)) {
    + struct tomoyo_alias_entry *ptr;
    + /* Is this program allowed to be called via symbolic links? */
    + list1_for_each_entry(ptr, &tomoyo_alias_list, list) {
    + if (ptr->is_deleted ||
    + tomoyo_pathcmp(&r, ptr->original_name) ||
    + tomoyo_pathcmp(&s, ptr->aliased_name))
    + continue;
    + memset(real_program_name, 0, TOMOYO_MAX_PATHNAME_LEN);
    + strncpy(real_program_name, ptr->aliased_name->name,
    + TOMOYO_MAX_PATHNAME_LEN - 1);
    + tomoyo_fill_path_info(&r);
    + break;
    + }
    + }
    +
    + /* Check execute permission. */
    + retval = tomoyo_check_exec_perm(old_domain, &r, tmp);
    + if (retval < 0)
    + goto out;
    +
    + new_domain_name = tmp->buffer;
    + if (is_domain_initializer(old_domain->domainname, &r, &l)) {
    + /* Transit to the child of tomoyo_kernel_domain domain. */
    + snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1,
    + TOMOYO_ROOT_NAME " " "%s", real_program_name);
    + } else if (old_domain == &tomoyo_kernel_domain &&
    + !tomoyo_policy_loaded) {
    + /*
    + * Needn't to transit from kernel domain before starting
    + * /sbin/init. But transit from kernel domain if executing
    + * initializers because they might start before /sbin/init.
    + */
    + domain = old_domain;
    + } else if (is_domain_keeper(old_domain->domainname, &r, &l)) {
    + /* Keep current domain. */
    + domain = old_domain;
    + } else {
    + /* Normal domain transition. */
    + snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1,
    + "%s %s", old_domain_name, real_program_name);
    + }
    + if (domain || strlen(new_domain_name) >= TOMOYO_MAX_PATHNAME_LEN)
    + goto done;
    + domain = tomoyo_find_domain(new_domain_name);
    + if (domain)
    + goto done;
    + if (is_enforce)
    + goto done;
    + domain = tomoyo_find_or_assign_new_domain(new_domain_name,
    + old_domain->profile);
    + done:
    + if (domain)
    + goto out;
    + printk(KERN_WARNING "TOMOYO-ERROR: Domain '%s' not defined.\n",
    + new_domain_name);
    + if (is_enforce)
    + retval = -EPERM;
    + else
    + tomoyo_set_domain_flag(old_domain, false,
    + TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED);
    + out:
    + tomoyo_free(real_program_name);
    + tomoyo_free(symlink_program_name);
    + *next_domain = domain ? domain : old_domain;
    + tomoyo_free(tmp);
    + return retval;
    +}
    --


    \
     
     \ /
      Last update: 2008-11-20 12:43    [W:3.800 / U:0.232 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site