Fixed MTP to work with TWRP

security/tomoyo/audit.c

@@ -0,0 +1,468 @@
+/*
+ * security/tomoyo/audit.c
+ *
+ * Copyright (C) 2005-2011  NTT DATA CORPORATION
+ */
+
+#include "common.h"
+#include <linux/slab.h>
+
+/**
+ * tomoyo_print_bprm - Print "struct linux_binprm" for auditing.
+ *
+ * @bprm: Pointer to "struct linux_binprm".
+ * @dump: Pointer to "struct tomoyo_page_dump".
+ *
+ * Returns the contents of @bprm on success, NULL otherwise.
+ *
+ * This function uses kzalloc(), so caller must kfree() if this function
+ * didn't return NULL.
+ */
+static char *tomoyo_print_bprm(struct linux_binprm *bprm,
+			       struct tomoyo_page_dump *dump)
+{
+	static const int tomoyo_buffer_len = 4096 * 2;
+	char *buffer = kzalloc(tomoyo_buffer_len, GFP_NOFS);
+	char *cp;
+	char *last_start;
+	int len;
+	unsigned long pos = bprm->p;
+	int offset = pos % PAGE_SIZE;
+	int argv_count = bprm->argc;
+	int envp_count = bprm->envc;
+	bool truncated = false;
+	if (!buffer)
+		return NULL;
+	len = snprintf(buffer, tomoyo_buffer_len - 1, "argv[]={ ");
+	cp = buffer + len;
+	if (!argv_count) {
+		memmove(cp, "} envp[]={ ", 11);
+		cp += 11;
+	}
+	last_start = cp;
+	while (argv_count || envp_count) {
+		if (!tomoyo_dump_page(bprm, pos, dump))
+			goto out;
+		pos += PAGE_SIZE - offset;
+		/* Read. */
+		while (offset < PAGE_SIZE) {
+			const char *kaddr = dump->data;
+			const unsigned char c = kaddr[offset++];
+			if (cp == last_start)
+				*cp++ = '"';
+			if (cp >= buffer + tomoyo_buffer_len - 32) {
+				/* Reserve some room for "..." string. */
+				truncated = true;
+			} else if (c == '\\') {
+				*cp++ = '\\';
+				*cp++ = '\\';
+			} else if (c > ' ' && c < 127) {
+				*cp++ = c;
+			} else if (!c) {
+				*cp++ = '"';
+				*cp++ = ' ';
+				last_start = cp;
+			} else {
+				*cp++ = '\\';
+				*cp++ = (c >> 6) + '0';
+				*cp++ = ((c >> 3) & 7) + '0';
+				*cp++ = (c & 7) + '0';
+			}
+			if (c)
+				continue;
+			if (argv_count) {
+				if (--argv_count == 0) {
+					if (truncated) {
+						cp = last_start;
+						memmove(cp, "... ", 4);
+						cp += 4;
+					}
+					memmove(cp, "} envp[]={ ", 11);
+					cp += 11;
+					last_start = cp;
+					truncated = false;
+				}
+			} else if (envp_count) {
+				if (--envp_count == 0) {
+					if (truncated) {
+						cp = last_start;
+						memmove(cp, "... ", 4);
+						cp += 4;
+					}
+				}
+			}
+			if (!argv_count && !envp_count)
+				break;
+		}
+		offset = 0;
+	}
+	*cp++ = '}';
+	*cp = '\0';
+	return buffer;
+out:
+	snprintf(buffer, tomoyo_buffer_len - 1,
+		 "argv[]={ ... } envp[]= { ... }");
+	return buffer;
+}
+
+/**
+ * tomoyo_filetype - Get string representation of file type.
+ *
+ * @mode: Mode value for stat().
+ *
+ * Returns file type string.
+ */
+static inline const char *tomoyo_filetype(const umode_t mode)
+{
+	switch (mode & S_IFMT) {
+	case S_IFREG:
+	case 0:
+		return tomoyo_condition_keyword[TOMOYO_TYPE_IS_FILE];
+	case S_IFDIR:
+		return tomoyo_condition_keyword[TOMOYO_TYPE_IS_DIRECTORY];
+	case S_IFLNK:
+		return tomoyo_condition_keyword[TOMOYO_TYPE_IS_SYMLINK];
+	case S_IFIFO:
+		return tomoyo_condition_keyword[TOMOYO_TYPE_IS_FIFO];
+	case S_IFSOCK:
+		return tomoyo_condition_keyword[TOMOYO_TYPE_IS_SOCKET];
+	case S_IFBLK:
+		return tomoyo_condition_keyword[TOMOYO_TYPE_IS_BLOCK_DEV];
+	case S_IFCHR:
+		return tomoyo_condition_keyword[TOMOYO_TYPE_IS_CHAR_DEV];
+	}
+	return "unknown"; /* This should not happen. */
+}
+
+/**
+ * tomoyo_print_header - Get header line of audit log.
+ *
+ * @r: Pointer to "struct tomoyo_request_info".
+ *
+ * Returns string representation.
+ *
+ * This function uses kmalloc(), so caller must kfree() if this function
+ * didn't return NULL.
+ */
+static char *tomoyo_print_header(struct tomoyo_request_info *r)
+{
+	struct tomoyo_time stamp;
+	const pid_t gpid = task_pid_nr(current);
+	struct tomoyo_obj_info *obj = r->obj;
+	static const int tomoyo_buffer_len = 4096;
+	char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
+	int pos;
+	u8 i;
+	if (!buffer)
+		return NULL;
+
+	tomoyo_convert_time(get_seconds(), &stamp);
+
+	pos = snprintf(buffer, tomoyo_buffer_len - 1,
+		       "#%04u/%02u/%02u %02u:%02u:%02u# profile=%u mode=%s "
+		       "granted=%s (global-pid=%u) task={ pid=%u ppid=%u "
+		       "uid=%u gid=%u euid=%u egid=%u suid=%u sgid=%u "
+		       "fsuid=%u fsgid=%u }", stamp.year, stamp.month,
+		       stamp.day, stamp.hour, stamp.min, stamp.sec, r->profile,
+		       tomoyo_mode[r->mode], tomoyo_yesno(r->granted), gpid,
+		       tomoyo_sys_getpid(), tomoyo_sys_getppid(),
+		       from_kuid(&init_user_ns, current_uid()),
+		       from_kgid(&init_user_ns, current_gid()),
+		       from_kuid(&init_user_ns, current_euid()),
+		       from_kgid(&init_user_ns, current_egid()),
+		       from_kuid(&init_user_ns, current_suid()),
+		       from_kgid(&init_user_ns, current_sgid()),
+		       from_kuid(&init_user_ns, current_fsuid()),
+		       from_kgid(&init_user_ns, current_fsgid()));
+	if (!obj)
+		goto no_obj_info;
+	if (!obj->validate_done) {
+		tomoyo_get_attributes(obj);
+		obj->validate_done = true;
+	}
+	for (i = 0; i < TOMOYO_MAX_PATH_STAT; i++) {
+		struct tomoyo_mini_stat *stat;
+		unsigned int dev;
+		umode_t mode;
+		if (!obj->stat_valid[i])
+			continue;
+		stat = &obj->stat[i];
+		dev = stat->dev;
+		mode = stat->mode;
+		if (i & 1) {
+			pos += snprintf(buffer + pos,
+					tomoyo_buffer_len - 1 - pos,
+					" path%u.parent={ uid=%u gid=%u "
+					"ino=%lu perm=0%o }", (i >> 1) + 1,
+					from_kuid(&init_user_ns, stat->uid),
+					from_kgid(&init_user_ns, stat->gid),
+					(unsigned long)stat->ino,
+					stat->mode & S_IALLUGO);
+			continue;
+		}
+		pos += snprintf(buffer + pos, tomoyo_buffer_len - 1 - pos,
+				" path%u={ uid=%u gid=%u ino=%lu major=%u"
+				" minor=%u perm=0%o type=%s", (i >> 1) + 1,
+				from_kuid(&init_user_ns, stat->uid),
+				from_kgid(&init_user_ns, stat->gid),
+				(unsigned long)stat->ino,
+				MAJOR(dev), MINOR(dev),
+				mode & S_IALLUGO, tomoyo_filetype(mode));
+		if (S_ISCHR(mode) || S_ISBLK(mode)) {
+			dev = stat->rdev;
+			pos += snprintf(buffer + pos,
+					tomoyo_buffer_len - 1 - pos,
+					" dev_major=%u dev_minor=%u",
+					MAJOR(dev), MINOR(dev));
+		}
+		pos += snprintf(buffer + pos, tomoyo_buffer_len - 1 - pos,
+				" }");
+	}
+no_obj_info:
+	if (pos < tomoyo_buffer_len - 1)
+		return buffer;
+	kfree(buffer);
+	return NULL;
+}
+
+/**
+ * tomoyo_init_log - Allocate buffer for audit logs.
+ *
+ * @r:    Pointer to "struct tomoyo_request_info".
+ * @len:  Buffer size needed for @fmt and @args.
+ * @fmt:  The printf()'s format string.
+ * @args: va_list structure for @fmt.
+ *
+ * Returns pointer to allocated memory.
+ *
+ * This function uses kzalloc(), so caller must kfree() if this function
+ * didn't return NULL.
+ */
+char *tomoyo_init_log(struct tomoyo_request_info *r, int len, const char *fmt,
+		      va_list args)
+{
+	char *buf = NULL;
+	char *bprm_info = NULL;
+	const char *header = NULL;
+	char *realpath = NULL;
+	const char *symlink = NULL;
+	int pos;
+	const char *domainname = r->domain->domainname->name;
+	header = tomoyo_print_header(r);
+	if (!header)
+		return NULL;
+	/* +10 is for '\n' etc. and '\0'. */
+	len += strlen(domainname) + strlen(header) + 10;
+	if (r->ee) {
+		struct file *file = r->ee->bprm->file;
+		realpath = tomoyo_realpath_from_path(&file->f_path);
+		bprm_info = tomoyo_print_bprm(r->ee->bprm, &r->ee->dump);
+		if (!realpath || !bprm_info)
+			goto out;
+		/* +80 is for " exec={ realpath=\"%s\" argc=%d envc=%d %s }" */
+		len += strlen(realpath) + 80 + strlen(bprm_info);
+	} else if (r->obj && r->obj->symlink_target) {
+		symlink = r->obj->symlink_target->name;
+		/* +18 is for " symlink.target=\"%s\"" */
+		len += 18 + strlen(symlink);
+	}
+	len = tomoyo_round2(len);
+	buf = kzalloc(len, GFP_NOFS);
+	if (!buf)
+		goto out;
+	len--;
+	pos = snprintf(buf, len, "%s", header);
+	if (realpath) {
+		struct linux_binprm *bprm = r->ee->bprm;
+		pos += snprintf(buf + pos, len - pos,
+				" exec={ realpath=\"%s\" argc=%d envc=%d %s }",
+				realpath, bprm->argc, bprm->envc, bprm_info);
+	} else if (symlink)
+		pos += snprintf(buf + pos, len - pos, " symlink.target=\"%s\"",
+				symlink);
+	pos += snprintf(buf + pos, len - pos, "\n%s\n", domainname);
+	vsnprintf(buf + pos, len - pos, fmt, args);
+out:
+	kfree(realpath);
+	kfree(bprm_info);
+	kfree(header);
+	return buf;
+}
+
+/* Wait queue for /sys/kernel/security/tomoyo/audit. */
+static DECLARE_WAIT_QUEUE_HEAD(tomoyo_log_wait);
+
+/* Structure for audit log. */
+struct tomoyo_log {
+	struct list_head list;
+	char *log;
+	int size;
+};
+
+/* The list for "struct tomoyo_log". */
+static LIST_HEAD(tomoyo_log);
+
+/* Lock for "struct list_head tomoyo_log". */
+static DEFINE_SPINLOCK(tomoyo_log_lock);
+
+/* Length of "stuct list_head tomoyo_log". */
+static unsigned int tomoyo_log_count;
+
+/**
+ * tomoyo_get_audit - Get audit mode.
+ *
+ * @ns:          Pointer to "struct tomoyo_policy_namespace".
+ * @profile:     Profile number.
+ * @index:       Index number of functionality.
+ * @is_granted:  True if granted log, false otherwise.
+ *
+ * Returns true if this request should be audited, false otherwise.
+ */
+static bool tomoyo_get_audit(const struct tomoyo_policy_namespace *ns,
+			     const u8 profile, const u8 index,
+			     const struct tomoyo_acl_info *matched_acl,
+			     const bool is_granted)
+{
+	u8 mode;
+	const u8 category = tomoyo_index2category[index] +
+		TOMOYO_MAX_MAC_INDEX;
+	struct tomoyo_profile *p;
+	if (!tomoyo_policy_loaded)
+		return false;
+	p = tomoyo_profile(ns, profile);
+	if (tomoyo_log_count >= p->pref[TOMOYO_PREF_MAX_AUDIT_LOG])
+		return false;
+	if (is_granted && matched_acl && matched_acl->cond &&
+	    matched_acl->cond->grant_log != TOMOYO_GRANTLOG_AUTO)
+		return matched_acl->cond->grant_log == TOMOYO_GRANTLOG_YES;
+	mode = p->config[index];
+	if (mode == TOMOYO_CONFIG_USE_DEFAULT)
+		mode = p->config[category];
+	if (mode == TOMOYO_CONFIG_USE_DEFAULT)
+		mode = p->default_config;
+	if (is_granted)
+		return mode & TOMOYO_CONFIG_WANT_GRANT_LOG;
+	return mode & TOMOYO_CONFIG_WANT_REJECT_LOG;
+}
+
+/**
+ * tomoyo_write_log2 - Write an audit log.
+ *
+ * @r:    Pointer to "struct tomoyo_request_info".
+ * @len:  Buffer size needed for @fmt and @args.
+ * @fmt:  The printf()'s format string.
+ * @args: va_list structure for @fmt.
+ *
+ * Returns nothing.
+ */
+void tomoyo_write_log2(struct tomoyo_request_info *r, int len, const char *fmt,
+		       va_list args)
+{
+	char *buf;
+	struct tomoyo_log *entry;
+	bool quota_exceeded = false;
+	if (!tomoyo_get_audit(r->domain->ns, r->profile, r->type,
+			      r->matched_acl, r->granted))
+		goto out;
+	buf = tomoyo_init_log(r, len, fmt, args);
+	if (!buf)
+		goto out;
+	entry = kzalloc(sizeof(*entry), GFP_NOFS);
+	if (!entry) {
+		kfree(buf);
+		goto out;
+	}
+	entry->log = buf;
+	len = tomoyo_round2(strlen(buf) + 1);
+	/*
+	 * The entry->size is used for memory quota checks.
+	 * Don't go beyond strlen(entry->log).
+	 */
+	entry->size = len + tomoyo_round2(sizeof(*entry));
+	spin_lock(&tomoyo_log_lock);
+	if (tomoyo_memory_quota[TOMOYO_MEMORY_AUDIT] &&
+	    tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] + entry->size >=
+	    tomoyo_memory_quota[TOMOYO_MEMORY_AUDIT]) {
+		quota_exceeded = true;
+	} else {
+		tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] += entry->size;
+		list_add_tail(&entry->list, &tomoyo_log);
+		tomoyo_log_count++;
+	}
+	spin_unlock(&tomoyo_log_lock);
+	if (quota_exceeded) {
+		kfree(buf);
+		kfree(entry);
+		goto out;
+	}
+	wake_up(&tomoyo_log_wait);
+out:
+	return;
+}
+
+/**
+ * tomoyo_write_log - Write an audit log.
+ *
+ * @r:   Pointer to "struct tomoyo_request_info".
+ * @fmt: The printf()'s format string, followed by parameters.
+ *
+ * Returns nothing.
+ */
+void tomoyo_write_log(struct tomoyo_request_info *r, const char *fmt, ...)
+{
+	va_list args;
+	int len;
+	va_start(args, fmt);
+	len = vsnprintf((char *) &len, 1, fmt, args) + 1;
+	va_end(args);
+	va_start(args, fmt);
+	tomoyo_write_log2(r, len, fmt, args);
+	va_end(args);
+}
+
+/**
+ * tomoyo_read_log - Read an audit log.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns nothing.
+ */
+void tomoyo_read_log(struct tomoyo_io_buffer *head)
+{
+	struct tomoyo_log *ptr = NULL;
+	if (head->r.w_pos)
+		return;
+	kfree(head->read_buf);
+	head->read_buf = NULL;
+	spin_lock(&tomoyo_log_lock);
+	if (!list_empty(&tomoyo_log)) {
+		ptr = list_entry(tomoyo_log.next, typeof(*ptr), list);
+		list_del(&ptr->list);
+		tomoyo_log_count--;
+		tomoyo_memory_used[TOMOYO_MEMORY_AUDIT] -= ptr->size;
+	}
+	spin_unlock(&tomoyo_log_lock);
+	if (ptr) {
+		head->read_buf = ptr->log;
+		head->r.w[head->r.w_pos++] = head->read_buf;
+		kfree(ptr);
+	}
+}
+
+/**
+ * tomoyo_poll_log - Wait for an audit log.
+ *
+ * @file: Pointer to "struct file".
+ * @wait: Pointer to "poll_table". Maybe NULL.
+ *
+ * Returns POLLIN | POLLRDNORM when ready to read an audit log.
+ */
+unsigned int tomoyo_poll_log(struct file *file, poll_table *wait)
+{
+	if (tomoyo_log_count)
+		return POLLIN | POLLRDNORM;
+	poll_wait(file, &tomoyo_log_wait, wait);
+	if (tomoyo_log_count)
+		return POLLIN | POLLRDNORM;
+	return 0;
+}