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/* |
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* fs/tomoyo_signal.c |
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* |
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* Implementation of the Domain-Based Mandatory Access Control. |
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* |
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* Copyright (C) 2005-2007 NTT DATA CORPORATION |
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* |
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* Version: 1.5.0 2007/09/20 |
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* |
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* This file is applicable to both 2.4.30 and 2.6.11 and later. |
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* See README.ccs for ChangeLog. |
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* |
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*/ |
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/***** TOMOYO Linux start. *****/ |
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|
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#include <linux/ccs_common.h> |
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#include <linux/tomoyo.h> |
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#include <linux/realpath.h> |
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|
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/************************* VARIABLES *************************/ |
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|
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/* The initial domain. */ |
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extern struct domain_info KERNEL_DOMAIN; |
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|
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extern struct semaphore domain_acl_lock; |
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|
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/************************* AUDIT FUNCTIONS *************************/ |
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|
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static int AuditSignalLog(const int signal, const struct path_info *dest_domain, const int is_granted) |
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{ |
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char *buf; |
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int len; |
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if (CanSaveAuditLog(is_granted) < 0) return -ENOMEM; |
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len = dest_domain->total_len; |
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if ((buf = InitAuditLog(&len)) == NULL) return -ENOMEM; |
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snprintf(buf + strlen(buf), len - strlen(buf) - 1, KEYWORD_ALLOW_SIGNAL "%d %s\n", signal, dest_domain->name); |
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return WriteAuditLog(buf, is_granted); |
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} |
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|
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/************************* SIGNAL ACL HANDLER *************************/ |
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|
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static int AddSignalEntry(const int sig, const char *dest_pattern, struct domain_info *domain, const u8 is_add, const struct condition_list *condition) |
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{ |
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struct acl_info *ptr; |
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const struct path_info *saved_dest_pattern; |
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const u16 hash = sig; |
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int error = -ENOMEM; |
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if (!domain) return -EINVAL; |
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if (!dest_pattern || !IsCorrectDomain(dest_pattern, __FUNCTION__)) return -EINVAL; |
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if ((saved_dest_pattern = SaveName(dest_pattern)) == NULL) return -ENOMEM; |
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down(&domain_acl_lock); |
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if (is_add) { |
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if ((ptr = domain->first_acl_ptr) == NULL) goto first_entry; |
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while (1) { |
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struct signal_acl_record *new_ptr = (struct signal_acl_record *) ptr; |
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if (ptr->type == TYPE_SIGNAL_ACL && new_ptr->sig == hash && ptr->cond == condition) { |
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if (!pathcmp(new_ptr->domainname, saved_dest_pattern)) { |
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ptr->is_deleted = 0; |
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/* Found. Nothing to do. */ |
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error = 0; |
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break; |
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} |
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} |
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if (ptr->next) { |
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ptr = ptr->next; |
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continue; |
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} |
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first_entry: ; |
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if (is_add == 1 && TooManyDomainACL(domain)) break; |
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/* Not found. Append it to the tail. */ |
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if ((new_ptr = alloc_element(sizeof(*new_ptr))) == NULL) break; |
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new_ptr->head.type = TYPE_SIGNAL_ACL; |
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new_ptr->sig = hash; |
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new_ptr->head.cond = condition; |
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new_ptr->domainname = saved_dest_pattern; |
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error = AddDomainACL(ptr, domain, (struct acl_info *) new_ptr); |
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break; |
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} |
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} else { |
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error = -ENOENT; |
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for (ptr = domain->first_acl_ptr; ptr; ptr = ptr->next) { |
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struct signal_acl_record *ptr2 = (struct signal_acl_record *) ptr; |
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if (ptr->type != TYPE_SIGNAL_ACL || ptr->is_deleted || ptr2->sig != hash || ptr->cond != condition) continue; |
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if (pathcmp(ptr2->domainname, saved_dest_pattern)) continue; |
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error = DelDomainACL(ptr); |
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break; |
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} |
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} |
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up(&domain_acl_lock); |
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return error; |
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} |
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|
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int CheckSignalACL(const int sig, const int pid) |
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{ |
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struct domain_info *domain = current->domain_info; |
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struct domain_info *dest = NULL; |
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const char *dest_pattern; |
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struct acl_info *ptr; |
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const u16 hash = sig; |
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const int is_enforce = CheckCCSEnforce(CCS_TOMOYO_MAC_FOR_SIGNAL); |
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if (!CheckCCSFlags(CCS_TOMOYO_MAC_FOR_SIGNAL)) return 0; |
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if (!sig) return 0; /* No check for NULL signal. */ |
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if (current->pid == pid) { |
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AuditSignalLog(sig, domain->domainname, 1); |
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return 0; /* No check for self. */ |
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} |
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{ /* Simplified checking. */ |
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struct task_struct *p = NULL; |
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read_lock(&tasklist_lock); |
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if (pid > 0) p = find_task_by_pid((pid_t) pid); |
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else if (pid == 0) p = current; |
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else if (pid == -1) dest = &KERNEL_DOMAIN; |
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else p = find_task_by_pid((pid_t) -pid); |
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if (p) dest = p->domain_info; |
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read_unlock(&tasklist_lock); |
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if (!dest) return 0; /* I can't find destinatioin. */ |
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} |
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if (domain == dest) { |
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AuditSignalLog(sig, dest->domainname, 1); |
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return 0; |
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} |
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dest_pattern = dest->domainname->name; |
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for (ptr = domain->first_acl_ptr; ptr; ptr = ptr->next) { |
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struct signal_acl_record *ptr2 = (struct signal_acl_record *) ptr; |
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if (ptr->type == TYPE_SIGNAL_ACL && ptr->is_deleted == 0 && ptr2->sig == hash && CheckCondition(ptr->cond, NULL) == 0) { |
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const int len = ptr2->domainname->total_len; |
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if (strncmp(ptr2->domainname->name, dest_pattern, len) == 0 && (dest_pattern[len] == ' ' || dest_pattern[len] == '\0')) break; |
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} |
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} |
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if (ptr) { |
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AuditSignalLog(sig, dest->domainname, 1); |
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return 0; |
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} |
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if (TomoyoVerboseMode()) { |
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printk("TOMOYO-%s: Signal %d to %s denied for %s\n", GetMSG(is_enforce), sig, GetLastName(dest), GetLastName(domain)); |
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} |
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AuditSignalLog(sig, dest->domainname, 0); |
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if (is_enforce) return CheckSupervisor("%s\n" KEYWORD_ALLOW_SIGNAL "%d %s\n", domain->domainname->name, sig, dest_pattern); |
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if (CheckCCSAccept(CCS_TOMOYO_MAC_FOR_SIGNAL)) AddSignalEntry(sig, dest_pattern, domain, 1, NULL); |
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return 0; |
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} |
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EXPORT_SYMBOL(CheckSignalACL); |
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|
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int AddSignalPolicy(char *data, struct domain_info *domain, const int is_delete) |
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{ |
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int sig; |
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char *domainname = strchr(data, ' '); |
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if (sscanf(data, "%d", &sig) == 1 && domainname && IsDomainDef(domainname + 1)) { |
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const struct condition_list *condition = NULL; |
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const char *cp = FindConditionPart(domainname + 1); |
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if (cp && (condition = FindOrAssignNewCondition(cp)) == NULL) return -EINVAL; |
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return AddSignalEntry(sig, domainname + 1, domain, is_delete ? 0 : -1, condition); |
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} |
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return -EINVAL; |
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} |
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|
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/***** TOMOYO Linux end. *****/ |