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-rw-r--r--security/tomoyo/audit.c479
1 files changed, 479 insertions, 0 deletions
diff --git a/security/tomoyo/audit.c b/security/tomoyo/audit.c
new file mode 100644
index 0000000000..610c1536cf
--- /dev/null
+++ b/security/tomoyo/audit.c
@@ -0,0 +1,479 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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(ktime_get_real_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],
+ str_yes_no(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 = kmalloc_size_roundup(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 "struct 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.
+ * @matched_acl: Pointer to "struct tomoyo_acl_info".
+ * @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 = kmalloc_size_roundup(strlen(buf) + 1);
+ /*
+ * The entry->size is used for memory quota checks.
+ * Don't go beyond strlen(entry->log).
+ */
+ entry->size = len + kmalloc_size_roundup(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(NULL, 0, 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 EPOLLIN | EPOLLRDNORM when ready to read an audit log.
+ */
+__poll_t tomoyo_poll_log(struct file *file, poll_table *wait)
+{
+ if (tomoyo_log_count)
+ return EPOLLIN | EPOLLRDNORM;
+ poll_wait(file, &tomoyo_log_wait, wait);
+ if (tomoyo_log_count)
+ return EPOLLIN | EPOLLRDNORM;
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 07:43:36 +0000