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When a signed policy is not mandatory, userspace can write IMA policy rules
directly to the securityfs policy file:
echo -e "measure func=BPRM_CHECK mask=MAY_EXEC\n" \
"audit func=BPRM_CHECK mask=MAY_EXEC\n" \
> /sys/kernel/security/ima/policy
or by cat'ing the entire IMA custom policy file:
cat ima-policy-file > /sys/kernel/security/ima/policy
Because these rules originate from userspace and cross the userspace/kernel
trust boundary, measure the raw write buffer before parsing, regardless of
whether the new policy will be accepted or not. This can be caught when
'measure func=POLICY_CHECK' is enabled (e.g., ima_policy=tcb). The
measurement template is forced to ima-buf.
This follows the "measure & load" paradigm, exposing potential bugs in
the policy code and detecting attempts to corrupt IMA. It also completes
the POLICY_CHECK hook, which already measures partial policy load by file.
To verify the template data hash value, convert the buffer policy data
to binary:
grep "ima_policy_written" \
/sys/kernel/security/integrity/ima/ascii_runtime_measurements | \
tail -1 | cut -d' ' -f 6 | xxd -r -p | sha256sum
Suggested-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Enrico Bravi <enrico.bravi@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
857 lines
20 KiB
C
857 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 2005,2006,2007,2008 IBM Corporation
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*
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* Authors:
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* Kylene Hall <kjhall@us.ibm.com>
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* Reiner Sailer <sailer@us.ibm.com>
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* Mimi Zohar <zohar@us.ibm.com>
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*
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* File: ima_fs.c
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* implemenents security file system for reporting
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* current measurement list and IMA statistics
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*/
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#include <linux/fcntl.h>
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#include <linux/kernel_read_file.h>
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#include <linux/slab.h>
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#include <linux/init.h>
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#include <linux/seq_file.h>
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#include <linux/rculist.h>
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#include <linux/rcupdate.h>
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#include <linux/parser.h>
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#include <linux/vmalloc.h>
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#include "ima.h"
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/*
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* Requests:
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* 'A\n': stage the entire measurements list
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* 'D\n': delete all staged measurements
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* '[1, ULONG_MAX]\n' delete N measurements records
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*/
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#define STAGED_REQ_LENGTH 21
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/* lock for protecting concurrent IMA policy updates */
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DEFINE_MUTEX(ima_write_mutex);
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static DEFINE_MUTEX(ima_measure_mutex);
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static long ima_measure_users;
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static struct task_struct *measure_writer;
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static long measure_writer_extra_writes;
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bool ima_canonical_fmt;
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static int __init default_canonical_fmt_setup(char *str)
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{
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#ifdef __BIG_ENDIAN
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ima_canonical_fmt = true;
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#endif
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return 1;
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}
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__setup("ima_canonical_fmt", default_canonical_fmt_setup);
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static int valid_policy = 1;
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static ssize_t ima_show_counter(char __user *buf, size_t count, loff_t *ppos,
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atomic_long_t *val)
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{
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char tmpbuf[32]; /* greater than largest 'long' string value */
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ssize_t len;
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len = scnprintf(tmpbuf, sizeof(tmpbuf), "%li\n", atomic_long_read(val));
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return simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
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}
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static ssize_t ima_show_num_violations(struct file *filp, char __user *buf,
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size_t count, loff_t *ppos)
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{
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return ima_show_counter(buf, count, ppos, &ima_num_violations);
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}
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static const struct file_operations ima_num_violations_ops = {
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.read = ima_show_num_violations,
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.llseek = generic_file_llseek,
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};
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static ssize_t ima_show_measurements_count(struct file *filp,
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char __user *buf,
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size_t count, loff_t *ppos)
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{
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return ima_show_counter(buf, count, ppos, &ima_num_records[BINARY]);
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}
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static const struct file_operations ima_measurements_count_ops = {
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.read = ima_show_measurements_count,
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.llseek = generic_file_llseek,
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};
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/* returns pointer to hlist_node */
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static void *_ima_measurements_start(struct seq_file *m, loff_t *pos,
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struct list_head *head)
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{
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loff_t l = *pos;
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struct ima_queue_entry *qe;
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/* we need a lock since pos could point beyond last element */
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rcu_read_lock();
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list_for_each_entry_rcu(qe, head, later) {
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if (!l--) {
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rcu_read_unlock();
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return qe;
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}
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}
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rcu_read_unlock();
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return NULL;
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}
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static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
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{
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return _ima_measurements_start(m, pos, &ima_measurements);
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}
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static void *ima_measurements_staged_start(struct seq_file *m, loff_t *pos)
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{
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return _ima_measurements_start(m, pos, &ima_measurements_staged);
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}
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static void *_ima_measurements_next(struct seq_file *m, void *v, loff_t *pos,
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struct list_head *head)
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{
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struct ima_queue_entry *qe = v;
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/* lock protects when reading beyond last element
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* against concurrent list-extension
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*/
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rcu_read_lock();
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qe = list_entry_rcu(qe->later.next, struct ima_queue_entry, later);
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rcu_read_unlock();
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(*pos)++;
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return (&qe->later == head) ? NULL : qe;
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}
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static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos)
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{
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return _ima_measurements_next(m, v, pos, &ima_measurements);
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}
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static void *ima_measurements_staged_next(struct seq_file *m, void *v,
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loff_t *pos)
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{
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return _ima_measurements_next(m, v, pos, &ima_measurements_staged);
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}
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static void ima_measurements_stop(struct seq_file *m, void *v)
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{
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}
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void ima_putc(struct seq_file *m, void *data, int datalen)
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{
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while (datalen--)
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seq_putc(m, *(char *)data++);
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}
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/* print format:
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* 32bit-le=pcr#
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* char[n]=template digest
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* 32bit-le=template name size
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* char[n]=template name
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* [eventdata length]
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* eventdata[n]=template specific data
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*/
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int ima_measurements_show(struct seq_file *m, void *v)
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{
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/* the list never shrinks, so we don't need a lock here */
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struct ima_queue_entry *qe = v;
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struct ima_template_entry *e;
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char *template_name;
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u32 pcr, namelen, template_data_len; /* temporary fields */
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bool is_ima_template = false;
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int i, algo_idx;
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algo_idx = ima_sha1_idx;
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if (m->file != NULL)
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algo_idx = (unsigned long)file_inode(m->file)->i_private;
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/* get entry */
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e = qe->entry;
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if (e == NULL)
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return -1;
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template_name = (e->template_desc->name[0] != '\0') ?
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e->template_desc->name : e->template_desc->fmt;
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/*
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* 1st: PCRIndex
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* PCR used defaults to the same (config option) in
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* little-endian format, unless set in policy
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*/
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pcr = !ima_canonical_fmt ? e->pcr : (__force u32)cpu_to_le32(e->pcr);
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ima_putc(m, &pcr, sizeof(e->pcr));
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/* 2nd: template digest */
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ima_putc(m, e->digests[algo_idx].digest,
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ima_algo_array[algo_idx].digest_size);
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/* 3rd: template name size */
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namelen = !ima_canonical_fmt ? strlen(template_name) :
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(__force u32)cpu_to_le32(strlen(template_name));
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ima_putc(m, &namelen, sizeof(namelen));
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/* 4th: template name */
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ima_putc(m, template_name, strlen(template_name));
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/* 5th: template length (except for 'ima' template) */
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if (strcmp(template_name, IMA_TEMPLATE_IMA_NAME) == 0)
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is_ima_template = true;
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if (!is_ima_template) {
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template_data_len = !ima_canonical_fmt ? e->template_data_len :
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(__force u32)cpu_to_le32(e->template_data_len);
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ima_putc(m, &template_data_len, sizeof(e->template_data_len));
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}
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/* 6th: template specific data */
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for (i = 0; i < e->template_desc->num_fields; i++) {
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enum ima_show_type show = IMA_SHOW_BINARY;
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const struct ima_template_field *field =
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e->template_desc->fields[i];
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if (is_ima_template && strcmp(field->field_id, "d") == 0)
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show = IMA_SHOW_BINARY_NO_FIELD_LEN;
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if (is_ima_template && strcmp(field->field_id, "n") == 0)
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show = IMA_SHOW_BINARY_OLD_STRING_FMT;
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field->field_show(m, show, &e->template_data[i]);
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}
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return 0;
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}
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static const struct seq_operations ima_measurments_seqops = {
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.start = ima_measurements_start,
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.next = ima_measurements_next,
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.stop = ima_measurements_stop,
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.show = ima_measurements_show
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};
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static const struct seq_operations ima_measurments_staged_seqops = {
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.start = ima_measurements_staged_start,
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.next = ima_measurements_staged_next,
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.stop = ima_measurements_stop,
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.show = ima_measurements_show
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};
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static int ima_measure_lock(bool write)
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{
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mutex_lock(&ima_measure_mutex);
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/* Overflow check. */
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if (!write && ima_measure_users == LONG_MAX) {
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mutex_unlock(&ima_measure_mutex);
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return -ENFILE;
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}
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/* Same writer can do additional writes or read/writes. */
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if (write && current == measure_writer) {
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measure_writer_extra_writes++;
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mutex_unlock(&ima_measure_mutex);
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return 0;
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}
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/*
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* ima_measure_users: > 0 open readers
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* ima_measure_users: == -1 open writer
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*/
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if ((write && ima_measure_users != 0) ||
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(!write && ima_measure_users < 0)) {
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mutex_unlock(&ima_measure_mutex);
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return -EBUSY;
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}
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if (write) {
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ima_measure_users--;
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/* Pointer valid, no reuse while the file descriptor is open. */
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measure_writer = current;
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} else {
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ima_measure_users++;
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}
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mutex_unlock(&ima_measure_mutex);
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return 0;
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}
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static void ima_measure_unlock(bool write)
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{
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mutex_lock(&ima_measure_mutex);
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/* Decrement additional writes or read/writes. */
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if (write && current == measure_writer &&
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measure_writer_extra_writes != 0) {
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measure_writer_extra_writes--;
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mutex_unlock(&ima_measure_mutex);
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return;
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}
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if (write) {
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ima_measure_users++;
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measure_writer = NULL;
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} else {
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ima_measure_users--;
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}
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mutex_unlock(&ima_measure_mutex);
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}
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static int _ima_measurements_open(struct inode *inode, struct file *file,
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const struct seq_operations *seq_ops)
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{
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bool write = (file->f_mode & FMODE_WRITE);
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int ret;
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if (write && !capable(CAP_SYS_ADMIN))
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return -EPERM;
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ret = ima_measure_lock(write);
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if (ret < 0)
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return ret;
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ret = seq_open(file, seq_ops);
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if (ret < 0)
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ima_measure_unlock(write);
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return ret;
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}
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static int ima_measurements_open(struct inode *inode, struct file *file)
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{
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return _ima_measurements_open(inode, file, &ima_measurments_seqops);
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}
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static int ima_measurements_release(struct inode *inode, struct file *file)
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{
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bool write = (file->f_mode & FMODE_WRITE);
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int ret;
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/* seq_release() always returns zero. */
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ret = seq_release(inode, file);
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ima_measure_unlock(write);
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return ret;
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}
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static int ima_measurements_staged_open(struct inode *inode, struct file *file)
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{
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return _ima_measurements_open(inode, file,
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&ima_measurments_staged_seqops);
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}
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static ssize_t _ima_measurements_write(struct file *file,
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const char __user *buf, size_t datalen,
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loff_t *ppos, bool staged_interface)
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{
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char req[STAGED_REQ_LENGTH];
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unsigned long req_value;
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int ret;
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if (datalen < 2 || datalen > STAGED_REQ_LENGTH)
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return -EINVAL;
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if (copy_from_user(req, buf, datalen) != 0)
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return -EFAULT;
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if (req[datalen - 1] != '\n')
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return -EINVAL;
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req[datalen - 1] = '\0';
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switch (req[0]) {
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case 'A':
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if (datalen != 2 || !staged_interface)
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return -EINVAL;
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ret = ima_queue_stage();
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break;
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case 'D':
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if (datalen != 2 || !staged_interface)
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return -EINVAL;
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ret = ima_queue_staged_delete_all();
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break;
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default:
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if (staged_interface)
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return -EINVAL;
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if (ima_flush_htable) {
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pr_debug("Deleting staged N measurements not supported when flushing the hash table is requested\n");
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return -EINVAL;
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}
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ret = kstrtoul(req, 10, &req_value);
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if (ret < 0)
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return ret;
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if (req_value == 0) {
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pr_debug("Must delete at least one entry\n");
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return -EINVAL;
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}
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ret = ima_queue_delete_partial(req_value);
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}
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if (ret < 0)
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return ret;
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return datalen;
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}
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static ssize_t ima_measurements_write(struct file *file, const char __user *buf,
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size_t datalen, loff_t *ppos)
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{
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return _ima_measurements_write(file, buf, datalen, ppos, false);
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}
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static ssize_t ima_measurements_staged_write(struct file *file,
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const char __user *buf,
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size_t datalen, loff_t *ppos)
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{
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return _ima_measurements_write(file, buf, datalen, ppos, true);
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}
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static const struct file_operations ima_measurements_ops = {
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.open = ima_measurements_open,
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.read = seq_read,
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.write = ima_measurements_write,
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.llseek = seq_lseek,
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.release = ima_measurements_release,
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};
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static const struct file_operations ima_measurements_staged_ops = {
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.open = ima_measurements_staged_open,
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.read = seq_read,
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.write = ima_measurements_staged_write,
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.llseek = seq_lseek,
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.release = ima_measurements_release,
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};
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void ima_print_digest(struct seq_file *m, u8 *digest, u32 size)
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{
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u32 i;
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for (i = 0; i < size; i++)
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seq_printf(m, "%02x", *(digest + i));
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}
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/* print in ascii */
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static int ima_ascii_measurements_show(struct seq_file *m, void *v)
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{
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/* the list never shrinks, so we don't need a lock here */
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struct ima_queue_entry *qe = v;
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struct ima_template_entry *e;
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char *template_name;
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int i, algo_idx;
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algo_idx = ima_sha1_idx;
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if (m->file != NULL)
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algo_idx = (unsigned long)file_inode(m->file)->i_private;
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/* get entry */
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e = qe->entry;
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if (e == NULL)
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return -1;
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template_name = (e->template_desc->name[0] != '\0') ?
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e->template_desc->name : e->template_desc->fmt;
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/* 1st: PCR used (config option) */
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seq_printf(m, "%2d ", e->pcr);
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/* 2nd: template hash */
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ima_print_digest(m, e->digests[algo_idx].digest,
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ima_algo_array[algo_idx].digest_size);
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/* 3th: template name */
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seq_printf(m, " %s", template_name);
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/* 4th: template specific data */
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for (i = 0; i < e->template_desc->num_fields; i++) {
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seq_puts(m, " ");
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if (e->template_data[i].len == 0)
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continue;
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e->template_desc->fields[i]->field_show(m, IMA_SHOW_ASCII,
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&e->template_data[i]);
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}
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seq_puts(m, "\n");
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return 0;
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}
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static const struct seq_operations ima_ascii_measurements_seqops = {
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.start = ima_measurements_start,
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.next = ima_measurements_next,
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.stop = ima_measurements_stop,
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.show = ima_ascii_measurements_show
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};
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static int ima_ascii_measurements_open(struct inode *inode, struct file *file)
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{
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return _ima_measurements_open(inode, file,
|
|
&ima_ascii_measurements_seqops);
|
|
}
|
|
|
|
static const struct file_operations ima_ascii_measurements_ops = {
|
|
.open = ima_ascii_measurements_open,
|
|
.read = seq_read,
|
|
.write = ima_measurements_write,
|
|
.llseek = seq_lseek,
|
|
.release = ima_measurements_release,
|
|
};
|
|
|
|
static const struct seq_operations ima_ascii_measurements_staged_seqops = {
|
|
.start = ima_measurements_staged_start,
|
|
.next = ima_measurements_staged_next,
|
|
.stop = ima_measurements_stop,
|
|
.show = ima_ascii_measurements_show
|
|
};
|
|
|
|
static int ima_ascii_measurements_staged_open(struct inode *inode,
|
|
struct file *file)
|
|
{
|
|
return _ima_measurements_open(inode, file,
|
|
&ima_ascii_measurements_staged_seqops);
|
|
}
|
|
|
|
static const struct file_operations ima_ascii_measurements_staged_ops = {
|
|
.open = ima_ascii_measurements_staged_open,
|
|
.read = seq_read,
|
|
.write = ima_measurements_staged_write,
|
|
.llseek = seq_lseek,
|
|
.release = ima_measurements_release,
|
|
};
|
|
|
|
static ssize_t ima_read_policy(char *path)
|
|
{
|
|
void *data = NULL;
|
|
char *datap;
|
|
size_t size;
|
|
int rc, pathlen = strlen(path);
|
|
|
|
char *p;
|
|
|
|
/* remove \n */
|
|
datap = path;
|
|
strsep(&datap, "\n");
|
|
|
|
rc = kernel_read_file_from_path(path, 0, &data, INT_MAX, NULL,
|
|
READING_POLICY);
|
|
if (rc < 0) {
|
|
pr_err("Unable to open file: %s (%d)", path, rc);
|
|
return rc;
|
|
}
|
|
size = rc;
|
|
rc = 0;
|
|
|
|
datap = data;
|
|
while (size > 0 && (p = strsep(&datap, "\n"))) {
|
|
pr_debug("rule: %s\n", p);
|
|
rc = ima_parse_add_rule(p);
|
|
if (rc < 0)
|
|
break;
|
|
size -= rc;
|
|
}
|
|
|
|
vfree(data);
|
|
if (rc < 0)
|
|
return rc;
|
|
else if (size)
|
|
return -EINVAL;
|
|
else
|
|
return pathlen;
|
|
}
|
|
|
|
static ssize_t ima_write_policy(struct file *file, const char __user *buf,
|
|
size_t datalen, loff_t *ppos)
|
|
{
|
|
char *data;
|
|
ssize_t result;
|
|
|
|
if (datalen >= PAGE_SIZE)
|
|
datalen = PAGE_SIZE - 1;
|
|
|
|
/* No partial writes. */
|
|
result = -EINVAL;
|
|
if (*ppos != 0)
|
|
goto out;
|
|
|
|
data = memdup_user_nul(buf, datalen);
|
|
if (IS_ERR(data)) {
|
|
result = PTR_ERR(data);
|
|
goto out;
|
|
}
|
|
|
|
result = mutex_lock_interruptible(&ima_write_mutex);
|
|
if (result < 0)
|
|
goto out_free;
|
|
|
|
if (data[0] == '/') {
|
|
result = ima_read_policy(data);
|
|
} else if (ima_appraise & IMA_APPRAISE_POLICY) {
|
|
pr_err("signed policy file (specified as an absolute pathname) required\n");
|
|
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
|
|
"policy_update", "signed policy required",
|
|
1, 0);
|
|
result = -EACCES;
|
|
} else {
|
|
ima_measure_raw_policy(data, datalen);
|
|
result = ima_parse_add_rule(data);
|
|
}
|
|
mutex_unlock(&ima_write_mutex);
|
|
out_free:
|
|
kfree(data);
|
|
out:
|
|
if (result < 0)
|
|
valid_policy = 0;
|
|
|
|
return result;
|
|
}
|
|
|
|
static struct dentry *ima_dir;
|
|
static struct dentry *ima_symlink;
|
|
|
|
enum ima_fs_flags {
|
|
IMA_FS_BUSY,
|
|
};
|
|
|
|
static unsigned long ima_fs_flags;
|
|
|
|
#ifdef CONFIG_IMA_READ_POLICY
|
|
static const struct seq_operations ima_policy_seqops = {
|
|
.start = ima_policy_start,
|
|
.next = ima_policy_next,
|
|
.stop = ima_policy_stop,
|
|
.show = ima_policy_show,
|
|
};
|
|
#endif
|
|
|
|
static int __init create_securityfs_measurement_lists(bool staging)
|
|
{
|
|
const struct file_operations *ascii_ops = &ima_ascii_measurements_ops;
|
|
const struct file_operations *binary_ops = &ima_measurements_ops;
|
|
umode_t permissions = (S_IRUSR | S_IRGRP | S_IWUSR | S_IWGRP);
|
|
const char *file_suffix = "";
|
|
int count = NR_BANKS(ima_tpm_chip);
|
|
|
|
if (staging) {
|
|
ascii_ops = &ima_ascii_measurements_staged_ops;
|
|
binary_ops = &ima_measurements_staged_ops;
|
|
file_suffix = "_staged";
|
|
}
|
|
|
|
if (ima_sha1_idx >= NR_BANKS(ima_tpm_chip))
|
|
count++;
|
|
|
|
for (int i = 0; i < count; i++) {
|
|
u16 algo = ima_algo_array[i].algo;
|
|
char file_name[NAME_MAX + 1];
|
|
struct dentry *dentry;
|
|
|
|
if (algo == HASH_ALGO__LAST)
|
|
snprintf(file_name, sizeof(file_name),
|
|
"ascii_runtime_measurements_tpm_alg_%x%s",
|
|
ima_tpm_chip->allocated_banks[i].alg_id,
|
|
file_suffix);
|
|
else
|
|
snprintf(file_name, sizeof(file_name),
|
|
"ascii_runtime_measurements_%s%s",
|
|
hash_algo_name[algo], file_suffix);
|
|
dentry = securityfs_create_file(file_name, permissions,
|
|
ima_dir, (void *)(uintptr_t)i,
|
|
ascii_ops);
|
|
if (IS_ERR(dentry))
|
|
return PTR_ERR(dentry);
|
|
|
|
if (algo == HASH_ALGO__LAST)
|
|
snprintf(file_name, sizeof(file_name),
|
|
"binary_runtime_measurements_tpm_alg_%x%s",
|
|
ima_tpm_chip->allocated_banks[i].alg_id,
|
|
file_suffix);
|
|
else
|
|
snprintf(file_name, sizeof(file_name),
|
|
"binary_runtime_measurements_%s%s",
|
|
hash_algo_name[algo], file_suffix);
|
|
|
|
dentry = securityfs_create_file(file_name, permissions,
|
|
ima_dir, (void *)(uintptr_t)i,
|
|
binary_ops);
|
|
if (IS_ERR(dentry))
|
|
return PTR_ERR(dentry);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init create_securityfs_staging_links(void)
|
|
{
|
|
struct dentry *dentry;
|
|
|
|
dentry = securityfs_create_symlink("binary_runtime_measurements_staged",
|
|
ima_dir, "binary_runtime_measurements_sha1_staged", NULL);
|
|
if (IS_ERR(dentry))
|
|
return PTR_ERR(dentry);
|
|
|
|
dentry = securityfs_create_symlink("ascii_runtime_measurements_staged",
|
|
ima_dir, "ascii_runtime_measurements_sha1_staged", NULL);
|
|
if (IS_ERR(dentry))
|
|
return PTR_ERR(dentry);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* ima_open_policy: sequentialize access to the policy file
|
|
*/
|
|
static int ima_open_policy(struct inode *inode, struct file *filp)
|
|
{
|
|
if (!(filp->f_flags & O_WRONLY)) {
|
|
#ifndef CONFIG_IMA_READ_POLICY
|
|
return -EACCES;
|
|
#else
|
|
if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
|
|
return -EACCES;
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
return seq_open(filp, &ima_policy_seqops);
|
|
#endif
|
|
}
|
|
if (test_and_set_bit(IMA_FS_BUSY, &ima_fs_flags))
|
|
return -EBUSY;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* ima_release_policy - start using the new measure policy rules.
|
|
*
|
|
* Initially, ima_measure points to the default policy rules, now
|
|
* point to the new policy rules, and remove the securityfs policy file,
|
|
* assuming a valid policy.
|
|
*/
|
|
static int ima_release_policy(struct inode *inode, struct file *file)
|
|
{
|
|
const char *cause = valid_policy ? "completed" : "failed";
|
|
|
|
if ((file->f_flags & O_ACCMODE) == O_RDONLY)
|
|
return seq_release(inode, file);
|
|
|
|
if (valid_policy && ima_check_policy() < 0) {
|
|
cause = "failed";
|
|
valid_policy = 0;
|
|
}
|
|
|
|
pr_info("policy update %s\n", cause);
|
|
integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
|
|
"policy_update", cause, !valid_policy, 0);
|
|
|
|
if (!valid_policy) {
|
|
ima_delete_rules();
|
|
valid_policy = 1;
|
|
clear_bit(IMA_FS_BUSY, &ima_fs_flags);
|
|
return 0;
|
|
}
|
|
|
|
ima_update_policy();
|
|
|
|
mutex_lock(&ima_write_mutex);
|
|
ima_measure_loaded_policy();
|
|
mutex_unlock(&ima_write_mutex);
|
|
#if !defined(CONFIG_IMA_WRITE_POLICY) && !defined(CONFIG_IMA_READ_POLICY)
|
|
securityfs_remove(file->f_path.dentry);
|
|
#elif defined(CONFIG_IMA_WRITE_POLICY)
|
|
clear_bit(IMA_FS_BUSY, &ima_fs_flags);
|
|
#elif defined(CONFIG_IMA_READ_POLICY)
|
|
inode->i_mode &= ~S_IWUSR;
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations ima_measure_policy_ops = {
|
|
.open = ima_open_policy,
|
|
.write = ima_write_policy,
|
|
.read = seq_read,
|
|
.release = ima_release_policy,
|
|
.llseek = generic_file_llseek,
|
|
};
|
|
|
|
int __init ima_fs_init(void)
|
|
{
|
|
struct dentry *dentry;
|
|
int ret;
|
|
|
|
ret = integrity_fs_init();
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ima_dir = securityfs_create_dir("ima", integrity_dir);
|
|
if (IS_ERR(ima_dir)) {
|
|
ret = PTR_ERR(ima_dir);
|
|
goto out;
|
|
}
|
|
|
|
ima_symlink = securityfs_create_symlink("ima", NULL, "integrity/ima",
|
|
NULL);
|
|
if (IS_ERR(ima_symlink)) {
|
|
ret = PTR_ERR(ima_symlink);
|
|
goto out;
|
|
}
|
|
|
|
ret = create_securityfs_measurement_lists(false);
|
|
if (ret == 0 && IS_ENABLED(CONFIG_IMA_STAGING)) {
|
|
ret = create_securityfs_measurement_lists(true);
|
|
if (ret == 0)
|
|
ret = create_securityfs_staging_links();
|
|
}
|
|
|
|
if (ret != 0)
|
|
goto out;
|
|
|
|
dentry = securityfs_create_symlink("binary_runtime_measurements", ima_dir,
|
|
"binary_runtime_measurements_sha1", NULL);
|
|
if (IS_ERR(dentry)) {
|
|
ret = PTR_ERR(dentry);
|
|
goto out;
|
|
}
|
|
|
|
dentry = securityfs_create_symlink("ascii_runtime_measurements", ima_dir,
|
|
"ascii_runtime_measurements_sha1", NULL);
|
|
if (IS_ERR(dentry)) {
|
|
ret = PTR_ERR(dentry);
|
|
goto out;
|
|
}
|
|
|
|
dentry = securityfs_create_file("runtime_measurements_count",
|
|
S_IRUSR | S_IRGRP, ima_dir, NULL,
|
|
&ima_measurements_count_ops);
|
|
if (IS_ERR(dentry)) {
|
|
ret = PTR_ERR(dentry);
|
|
goto out;
|
|
}
|
|
|
|
dentry = securityfs_create_file("violations", S_IRUSR | S_IRGRP,
|
|
ima_dir, NULL, &ima_num_violations_ops);
|
|
if (IS_ERR(dentry)) {
|
|
ret = PTR_ERR(dentry);
|
|
goto out;
|
|
}
|
|
|
|
dentry = securityfs_create_file("policy", POLICY_FILE_FLAGS,
|
|
ima_dir, NULL,
|
|
&ima_measure_policy_ops);
|
|
if (IS_ERR(dentry)) {
|
|
ret = PTR_ERR(dentry);
|
|
goto out;
|
|
}
|
|
|
|
return 0;
|
|
out:
|
|
securityfs_remove(ima_symlink);
|
|
securityfs_remove(ima_dir);
|
|
integrity_fs_fini();
|
|
|
|
return ret;
|
|
}
|