ccs-patch/fs/tomoyo_exec.c

/*
 * fs/tomoyo_exec.c
 *
 * Implementation of the Domain-Based Mandatory Access Control.
 *
 * Copyright (C) 2005-2007  NTT DATA CORPORATION
 *
 * Version: 1.3.2   2007/02/14
 *
 * This file is applicable to both 2.4.30 and 2.6.11 and later.
 * See README.ccs for ChangeLog.
 *
 */
/***** TOMOYO Linux start. *****/

#include <linux/ccs_common.h>
#include <linux/tomoyo.h>
#include <linux/realpath.h>

/*************************  VARIABLES  *************************/

extern struct semaphore domain_acl_lock;

/*************************  AUDIT FUNCTIONS  *************************/

#ifdef CONFIG_TOMOYO_AUDIT
static int AuditArgv0Log(const struct path_info *filename, const char *argv0, const int is_granted)
{
        char *buf;
        int len;
        if (CanSaveAuditLog(is_granted) < 0) return -ENOMEM;
        len = filename->total_len + strlen(argv0) + 8;
        if ((buf = InitAuditLog(&len)) == NULL) return -ENOMEM;
        snprintf(buf + strlen(buf), len - strlen(buf) - 1, KEYWORD_ALLOW_ARGV0 "%s %s\n", filename->name, argv0);
        return WriteAuditLog(buf, is_granted);
}

#else
static inline void AuditArgv0Log(const struct path_info *filename, const char *argv0, const int is_granted) {}
#endif

/*************************  ARGV0 MISMATCH HANDLER  *************************/

static int AddArgv0Entry(const char *filename, const char *argv0, struct domain_info *domain, const int is_delete, const struct condition_list *condition)
{
        struct acl_info *ptr;
        const struct path_info *saved_filename, *saved_argv0;
        int error = -ENOMEM;
        if (!IsCorrectPath(filename, 1, 0, -1, __FUNCTION__) || !IsCorrectPath(argv0, -1, 0, -1, __FUNCTION__) || strchr(argv0, '/')) return -EINVAL;
        if ((saved_filename = SaveName(filename)) == NULL || (saved_argv0 = SaveName(argv0)) == NULL) return -ENOMEM;
        down(&domain_acl_lock);
        if (!is_delete) {
                if ((ptr = domain->first_acl_ptr) == NULL) goto first_entry;
                while (1) {
                        ARGV0_ACL_RECORD *new_ptr;
                        if (ptr->type == TYPE_ARGV0_ACL && ptr->cond == condition) {
                                if (((ARGV0_ACL_RECORD *) ptr)->filename == saved_filename && ((ARGV0_ACL_RECORD *) ptr)->argv0 == saved_argv0) {
                                        ptr->is_deleted = 0;
                                        /* Found. Nothing to do. */
                                        error = 0;
                                        break;
                                }
                        }
                        if (ptr->next) {
                                ptr = ptr->next;
                                continue;
                        }
                first_entry: ;
                        /* Not found. Append it to the tail. */
                        if ((new_ptr = (ARGV0_ACL_RECORD *) alloc_element(sizeof(ARGV0_ACL_RECORD))) == NULL) break;
                        new_ptr->head.type = TYPE_ARGV0_ACL;
                        new_ptr->head.cond = condition;
                        new_ptr->filename = saved_filename;
                        new_ptr->argv0 = saved_argv0;
                        error = AddDomainACL(ptr, domain, (struct acl_info *) new_ptr);
                        break;
                }
        } else {
                error = -ENOENT;
                for (ptr = domain->first_acl_ptr; ptr; ptr = ptr->next) {
                        if (ptr->type != TYPE_ARGV0_ACL || ptr->is_deleted || ptr->cond != condition) continue;
                        if (((ARGV0_ACL_RECORD *) ptr)->filename != saved_filename || ((ARGV0_ACL_RECORD *) ptr)->argv0 != saved_argv0) continue;
                        error = DelDomainACL(ptr);
                        break;
                }
        }
        up(&domain_acl_lock);
        return error;
}

static int CheckArgv0ACL(const struct path_info *filename, const char *argv0_)
{
        const struct domain_info *domain = current->domain_info;
        int error = -EPERM;
        struct acl_info *ptr;
        struct path_info argv0;
        if (!CheckCCSFlags(CCS_TOMOYO_MAC_FOR_ARGV0)) return 0;
        argv0.name = argv0_;
        fill_path_info(&argv0);
        for (ptr = domain->first_acl_ptr; ptr; ptr = ptr->next) {
                if (ptr->type == TYPE_ARGV0_ACL && ptr->is_deleted == 0 && CheckCondition(ptr->cond, NULL) == 0 &&
                        PathMatchesToPattern(filename, ((ARGV0_ACL_RECORD *) ptr)->filename) &&
                        PathMatchesToPattern(&argv0, ((ARGV0_ACL_RECORD *) ptr)->argv0)) {
                        error = 0;
                        break;
                }
        }
        return error;
}

int CheckArgv0Perm(const struct path_info *filename, const char *argv0)
{
        int error = 0;
        if (!CheckCCSFlags(CCS_TOMOYO_MAC_FOR_ARGV0)) return 0;
        if (!filename || !argv0) return 0;
        error = CheckArgv0ACL(filename, argv0);
        AuditArgv0Log(filename, argv0, !error);
        if (error) {
                struct domain_info * const domain = current->domain_info;
                const int is_enforce = CheckCCSEnforce(CCS_TOMOYO_MAC_FOR_ARGV0);
                if (TomoyoVerboseMode()) {
                        printk("TOMOYO-%s: Run %s as %s denied for %s\n", GetMSG(is_enforce), filename->name, argv0, GetLastName(domain));
                }
                if (is_enforce) error = CheckSupervisor("%s\n" KEYWORD_ALLOW_ARGV0 "%s %s\n", domain->domainname->name, filename->name, argv0);
                else if (CheckCCSAccept(CCS_TOMOYO_MAC_FOR_ARGV0)) AddArgv0Entry(filename->name, argv0, domain, 0, NULL);
                if (!is_enforce) error = 0;
        }
        return error;
}

int AddArgv0Policy(char *data, struct domain_info *domain, const int is_delete)
{
        char *argv0 = strchr(data, ' ');
        char *cp;
        const struct condition_list *condition = NULL;
        if (!argv0) return -EINVAL;
        *argv0++ = '\0';
        cp = FindConditionPart(argv0);
        if (cp && (condition = FindOrAssignNewCondition(cp)) == NULL) return -EINVAL;
        return AddArgv0Entry(data, argv0, domain, is_delete, condition);
}

EXPORT_SYMBOL(CheckArgv0Perm);

/***** TOMOYO Linux end. *****/