--- /dev/null
- ima_measure_critical_data(DM_NAME, event_name, buf, buf_len, false);
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Microsoft Corporation
+ *
+ * Author: Tushar Sugandhi <tusharsu@linux.microsoft.com>
+ *
+ * File: dm-ima.c
+ * Enables IMA measurements for DM targets
+ */
+
+#include "dm-core.h"
+#include "dm-ima.h"
+
+#include <linux/ima.h>
+#include <crypto/hash.h>
+#include <linux/crypto.h>
+#include <crypto/hash_info.h>
+
+#define DM_MSG_PREFIX "ima"
+
+/*
+ * Internal function to prefix separator characters in input buffer with escape
+ * character, so that they don't interfere with the construction of key-value pairs,
+ * and clients can split the key1=val1,key2=val2,key3=val3; pairs properly.
+ */
+static void fix_separator_chars(char **buf)
+{
+ int l = strlen(*buf);
+ int i, j, sp = 0;
+
+ for (i = 0; i < l; i++)
+ if ((*buf)[i] == '\\' || (*buf)[i] == ';' || (*buf)[i] == '=' || (*buf)[i] == ',')
+ sp++;
+
+ if (!sp)
+ return;
+
+ for (i = l-1, j = i+sp; i >= 0; i--) {
+ (*buf)[j--] = (*buf)[i];
+ if ((*buf)[i] == '\\' || (*buf)[i] == ';' || (*buf)[i] == '=' || (*buf)[i] == ',')
+ (*buf)[j--] = '\\';
+ }
+}
+
+/*
+ * Internal function to allocate memory for IMA measurements.
+ */
+static void *dm_ima_alloc(size_t len, gfp_t flags, bool noio)
+{
+ unsigned int noio_flag;
+ void *ptr;
+
+ if (noio)
+ noio_flag = memalloc_noio_save();
+
+ ptr = kzalloc(len, flags);
+
+ if (noio)
+ memalloc_noio_restore(noio_flag);
+
+ return ptr;
+}
+
+/*
+ * Internal function to allocate and copy name and uuid for IMA measurements.
+ */
+static int dm_ima_alloc_and_copy_name_uuid(struct mapped_device *md, char **dev_name,
+ char **dev_uuid, bool noio)
+{
+ int r;
+ *dev_name = dm_ima_alloc(DM_NAME_LEN*2, GFP_KERNEL, noio);
+ if (!(*dev_name)) {
+ r = -ENOMEM;
+ goto error;
+ }
+
+ *dev_uuid = dm_ima_alloc(DM_UUID_LEN*2, GFP_KERNEL, noio);
+ if (!(*dev_uuid)) {
+ r = -ENOMEM;
+ goto error;
+ }
+
+ r = dm_copy_name_and_uuid(md, *dev_name, *dev_uuid);
+ if (r)
+ goto error;
+
+ fix_separator_chars(dev_name);
+ fix_separator_chars(dev_uuid);
+
+ return 0;
+error:
+ kfree(*dev_name);
+ kfree(*dev_uuid);
+ *dev_name = NULL;
+ *dev_uuid = NULL;
+ return r;
+}
+
+/*
+ * Internal function to allocate and copy device data for IMA measurements.
+ */
+static int dm_ima_alloc_and_copy_device_data(struct mapped_device *md, char **device_data,
+ unsigned int num_targets, bool noio)
+{
+ char *dev_name = NULL, *dev_uuid = NULL;
+ int r;
+
+ r = dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio);
+ if (r)
+ return r;
+
+ *device_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
+ if (!(*device_data)) {
+ r = -ENOMEM;
+ goto error;
+ }
+
+ scnprintf(*device_data, DM_IMA_DEVICE_BUF_LEN,
+ "name=%s,uuid=%s,major=%d,minor=%d,minor_count=%d,num_targets=%u;",
+ dev_name, dev_uuid, md->disk->major, md->disk->first_minor,
+ md->disk->minors, num_targets);
+error:
+ kfree(dev_name);
+ kfree(dev_uuid);
+ return r;
+}
+
+/*
+ * Internal wrapper function to call IMA to measure DM data.
+ */
+static void dm_ima_measure_data(const char *event_name, const void *buf, size_t buf_len,
+ bool noio)
+{
+ unsigned int noio_flag;
+
+ if (noio)
+ noio_flag = memalloc_noio_save();
+
++ ima_measure_critical_data(DM_NAME, event_name, buf, buf_len,
++ false, NULL, 0);
+
+ if (noio)
+ memalloc_noio_restore(noio_flag);
+}
+
+/*
+ * Internal function to allocate and copy current device capacity for IMA measurements.
+ */
+static int dm_ima_alloc_and_copy_capacity_str(struct mapped_device *md, char **capacity_str,
+ bool noio)
+{
+ sector_t capacity;
+
+ capacity = get_capacity(md->disk);
+
+ *capacity_str = dm_ima_alloc(DM_IMA_DEVICE_CAPACITY_BUF_LEN, GFP_KERNEL, noio);
+ if (!(*capacity_str))
+ return -ENOMEM;
+
+ scnprintf(*capacity_str, DM_IMA_DEVICE_BUF_LEN, "current_device_capacity=%llu;",
+ capacity);
+
+ return 0;
+}
+
+/*
+ * Initialize/reset the dm ima related data structure variables.
+ */
+void dm_ima_reset_data(struct mapped_device *md)
+{
+ memset(&(md->ima), 0, sizeof(md->ima));
+ md->ima.dm_version_str_len = strlen(DM_IMA_VERSION_STR);
+}
+
+/*
+ * Build up the IMA data for each target, and finally measure.
+ */
+void dm_ima_measure_on_table_load(struct dm_table *table, unsigned int status_flags)
+{
+ size_t device_data_buf_len, target_metadata_buf_len, target_data_buf_len, l = 0;
+ char *target_metadata_buf = NULL, *target_data_buf = NULL, *digest_buf = NULL;
+ char *ima_buf = NULL, *device_data_buf = NULL;
+ int digest_size, last_target_measured = -1, r;
+ status_type_t type = STATUSTYPE_IMA;
+ size_t cur_total_buf_len = 0;
+ unsigned int num_targets, i;
+ SHASH_DESC_ON_STACK(shash, NULL);
+ struct crypto_shash *tfm = NULL;
+ u8 *digest = NULL;
+ bool noio = false;
+ /*
+ * In below hash_alg_prefix_len assignment +1 is for the additional char (':'),
+ * when prefixing the hash value with the hash algorithm name. e.g. sha256:<hash_value>.
+ */
+ const size_t hash_alg_prefix_len = strlen(DM_IMA_TABLE_HASH_ALG) + 1;
+ char table_load_event_name[] = "dm_table_load";
+
+ ima_buf = dm_ima_alloc(DM_IMA_MEASUREMENT_BUF_LEN, GFP_KERNEL, noio);
+ if (!ima_buf)
+ return;
+
+ target_metadata_buf = dm_ima_alloc(DM_IMA_TARGET_METADATA_BUF_LEN, GFP_KERNEL, noio);
+ if (!target_metadata_buf)
+ goto error;
+
+ target_data_buf = dm_ima_alloc(DM_IMA_TARGET_DATA_BUF_LEN, GFP_KERNEL, noio);
+ if (!target_data_buf)
+ goto error;
+
+ num_targets = dm_table_get_num_targets(table);
+
+ if (dm_ima_alloc_and_copy_device_data(table->md, &device_data_buf, num_targets, noio))
+ goto error;
+
+ tfm = crypto_alloc_shash(DM_IMA_TABLE_HASH_ALG, 0, 0);
+ if (IS_ERR(tfm))
+ goto error;
+
+ shash->tfm = tfm;
+ digest_size = crypto_shash_digestsize(tfm);
+ digest = dm_ima_alloc(digest_size, GFP_KERNEL, noio);
+ if (!digest)
+ goto error;
+
+ r = crypto_shash_init(shash);
+ if (r)
+ goto error;
+
+ memcpy(ima_buf + l, DM_IMA_VERSION_STR, table->md->ima.dm_version_str_len);
+ l += table->md->ima.dm_version_str_len;
+
+ device_data_buf_len = strlen(device_data_buf);
+ memcpy(ima_buf + l, device_data_buf, device_data_buf_len);
+ l += device_data_buf_len;
+
+ for (i = 0; i < num_targets; i++) {
+ struct dm_target *ti = dm_table_get_target(table, i);
+
+ if (!ti)
+ goto error;
+
+ last_target_measured = 0;
+
+ /*
+ * First retrieve the target metadata.
+ */
+ scnprintf(target_metadata_buf, DM_IMA_TARGET_METADATA_BUF_LEN,
+ "target_index=%d,target_begin=%llu,target_len=%llu,",
+ i, ti->begin, ti->len);
+ target_metadata_buf_len = strlen(target_metadata_buf);
+
+ /*
+ * Then retrieve the actual target data.
+ */
+ if (ti->type->status)
+ ti->type->status(ti, type, status_flags, target_data_buf,
+ DM_IMA_TARGET_DATA_BUF_LEN);
+ else
+ target_data_buf[0] = '\0';
+
+ target_data_buf_len = strlen(target_data_buf);
+
+ /*
+ * Check if the total data can fit into the IMA buffer.
+ */
+ cur_total_buf_len = l + target_metadata_buf_len + target_data_buf_len;
+
+ /*
+ * IMA measurements for DM targets are best-effort.
+ * If the total data buffered so far, including the current target,
+ * is too large to fit into DM_IMA_MEASUREMENT_BUF_LEN, measure what
+ * we have in the current buffer, and continue measuring the remaining
+ * targets by prefixing the device metadata again.
+ */
+ if (unlikely(cur_total_buf_len >= DM_IMA_MEASUREMENT_BUF_LEN)) {
+ dm_ima_measure_data(table_load_event_name, ima_buf, l, noio);
+ r = crypto_shash_update(shash, (const u8 *)ima_buf, l);
+ if (r < 0)
+ goto error;
+
+ memset(ima_buf, 0, DM_IMA_MEASUREMENT_BUF_LEN);
+ l = 0;
+
+ /*
+ * Each new "dm_table_load" entry in IMA log should have device data
+ * prefix, so that multiple records from the same "dm_table_load" for
+ * a given device can be linked together.
+ */
+ memcpy(ima_buf + l, DM_IMA_VERSION_STR, table->md->ima.dm_version_str_len);
+ l += table->md->ima.dm_version_str_len;
+
+ memcpy(ima_buf + l, device_data_buf, device_data_buf_len);
+ l += device_data_buf_len;
+
+ /*
+ * If this iteration of the for loop turns out to be the last target
+ * in the table, dm_ima_measure_data("dm_table_load", ...) doesn't need
+ * to be called again, just the hash needs to be finalized.
+ * "last_target_measured" tracks this state.
+ */
+ last_target_measured = 1;
+ }
+
+ /*
+ * Fill-in all the target metadata, so that multiple targets for the same
+ * device can be linked together.
+ */
+ memcpy(ima_buf + l, target_metadata_buf, target_metadata_buf_len);
+ l += target_metadata_buf_len;
+
+ memcpy(ima_buf + l, target_data_buf, target_data_buf_len);
+ l += target_data_buf_len;
+ }
+
+ if (!last_target_measured) {
+ dm_ima_measure_data(table_load_event_name, ima_buf, l, noio);
+
+ r = crypto_shash_update(shash, (const u8 *)ima_buf, l);
+ if (r < 0)
+ goto error;
+ }
+
+ /*
+ * Finalize the table hash, and store it in table->md->ima.inactive_table.hash,
+ * so that the table data can be verified against the future device state change
+ * events, e.g. resume, rename, remove, table-clear etc.
+ */
+ r = crypto_shash_final(shash, digest);
+ if (r < 0)
+ goto error;
+
+ digest_buf = dm_ima_alloc((digest_size*2) + hash_alg_prefix_len + 1, GFP_KERNEL, noio);
+
+ if (!digest_buf)
+ goto error;
+
+ snprintf(digest_buf, hash_alg_prefix_len + 1, "%s:", DM_IMA_TABLE_HASH_ALG);
+
+ for (i = 0; i < digest_size; i++)
+ snprintf((digest_buf + hash_alg_prefix_len + (i*2)), 3, "%02x", digest[i]);
+
+ if (table->md->ima.active_table.hash != table->md->ima.inactive_table.hash)
+ kfree(table->md->ima.inactive_table.hash);
+
+ table->md->ima.inactive_table.hash = digest_buf;
+ table->md->ima.inactive_table.hash_len = strlen(digest_buf);
+ table->md->ima.inactive_table.num_targets = num_targets;
+
+ if (table->md->ima.active_table.device_metadata !=
+ table->md->ima.inactive_table.device_metadata)
+ kfree(table->md->ima.inactive_table.device_metadata);
+
+ table->md->ima.inactive_table.device_metadata = device_data_buf;
+ table->md->ima.inactive_table.device_metadata_len = device_data_buf_len;
+
+ goto exit;
+error:
+ kfree(digest_buf);
+ kfree(device_data_buf);
+exit:
+ kfree(digest);
+ if (tfm)
+ crypto_free_shash(tfm);
+ kfree(ima_buf);
+ kfree(target_metadata_buf);
+ kfree(target_data_buf);
+}
+
+/*
+ * Measure IMA data on device resume.
+ */
+void dm_ima_measure_on_device_resume(struct mapped_device *md, bool swap)
+{
+ char *device_table_data, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
+ char active[] = "active_table_hash=";
+ unsigned int active_len = strlen(active), capacity_len = 0;
+ unsigned int l = 0;
+ bool noio = true;
+ bool nodata = true;
+ int r;
+
+ device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
+ if (!device_table_data)
+ return;
+
+ r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+ if (r)
+ goto error;
+
+ memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
+ l += md->ima.dm_version_str_len;
+
+ if (swap) {
+ if (md->ima.active_table.hash != md->ima.inactive_table.hash)
+ kfree(md->ima.active_table.hash);
+
+ md->ima.active_table.hash = NULL;
+ md->ima.active_table.hash_len = 0;
+
+ if (md->ima.active_table.device_metadata !=
+ md->ima.inactive_table.device_metadata)
+ kfree(md->ima.active_table.device_metadata);
+
+ md->ima.active_table.device_metadata = NULL;
+ md->ima.active_table.device_metadata_len = 0;
+ md->ima.active_table.num_targets = 0;
+
+ if (md->ima.inactive_table.hash) {
+ md->ima.active_table.hash = md->ima.inactive_table.hash;
+ md->ima.active_table.hash_len = md->ima.inactive_table.hash_len;
+ md->ima.inactive_table.hash = NULL;
+ md->ima.inactive_table.hash_len = 0;
+ }
+
+ if (md->ima.inactive_table.device_metadata) {
+ md->ima.active_table.device_metadata =
+ md->ima.inactive_table.device_metadata;
+ md->ima.active_table.device_metadata_len =
+ md->ima.inactive_table.device_metadata_len;
+ md->ima.active_table.num_targets = md->ima.inactive_table.num_targets;
+ md->ima.inactive_table.device_metadata = NULL;
+ md->ima.inactive_table.device_metadata_len = 0;
+ md->ima.inactive_table.num_targets = 0;
+ }
+ }
+
+ if (md->ima.active_table.device_metadata) {
+ memcpy(device_table_data + l, md->ima.active_table.device_metadata,
+ md->ima.active_table.device_metadata_len);
+ l += md->ima.active_table.device_metadata_len;
+
+ nodata = false;
+ }
+
+ if (md->ima.active_table.hash) {
+ memcpy(device_table_data + l, active, active_len);
+ l += active_len;
+
+ memcpy(device_table_data + l, md->ima.active_table.hash,
+ md->ima.active_table.hash_len);
+ l += md->ima.active_table.hash_len;
+
+ memcpy(device_table_data + l, ";", 1);
+ l++;
+
+ nodata = false;
+ }
+
+ if (nodata) {
+ r = dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio);
+ if (r)
+ goto error;
+
+ scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
+ "%sname=%s,uuid=%s;device_resume=no_data;",
+ DM_IMA_VERSION_STR, dev_name, dev_uuid);
+ l += strlen(device_table_data);
+
+ }
+
+ capacity_len = strlen(capacity_str);
+ memcpy(device_table_data + l, capacity_str, capacity_len);
+ l += capacity_len;
+
+ dm_ima_measure_data("dm_device_resume", device_table_data, l, noio);
+
+ kfree(dev_name);
+ kfree(dev_uuid);
+error:
+ kfree(capacity_str);
+ kfree(device_table_data);
+}
+
+/*
+ * Measure IMA data on remove.
+ */
+void dm_ima_measure_on_device_remove(struct mapped_device *md, bool remove_all)
+{
+ char *device_table_data, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
+ char active_table_str[] = "active_table_hash=";
+ char inactive_table_str[] = "inactive_table_hash=";
+ char device_active_str[] = "device_active_metadata=";
+ char device_inactive_str[] = "device_inactive_metadata=";
+ char remove_all_str[] = "remove_all=";
+ unsigned int active_table_len = strlen(active_table_str);
+ unsigned int inactive_table_len = strlen(inactive_table_str);
+ unsigned int device_active_len = strlen(device_active_str);
+ unsigned int device_inactive_len = strlen(device_inactive_str);
+ unsigned int remove_all_len = strlen(remove_all_str);
+ unsigned int capacity_len = 0;
+ unsigned int l = 0;
+ bool noio = true;
+ bool nodata = true;
+ int r;
+
+ device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN*2, GFP_KERNEL, noio);
+ if (!device_table_data)
+ goto exit;
+
+ r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+ if (r) {
+ kfree(device_table_data);
+ goto exit;
+ }
+
+ memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
+ l += md->ima.dm_version_str_len;
+
+ if (md->ima.active_table.device_metadata) {
+ memcpy(device_table_data + l, device_active_str, device_active_len);
+ l += device_active_len;
+
+ memcpy(device_table_data + l, md->ima.active_table.device_metadata,
+ md->ima.active_table.device_metadata_len);
+ l += md->ima.active_table.device_metadata_len;
+
+ nodata = false;
+ }
+
+ if (md->ima.inactive_table.device_metadata) {
+ memcpy(device_table_data + l, device_inactive_str, device_inactive_len);
+ l += device_inactive_len;
+
+ memcpy(device_table_data + l, md->ima.inactive_table.device_metadata,
+ md->ima.inactive_table.device_metadata_len);
+ l += md->ima.inactive_table.device_metadata_len;
+
+ nodata = false;
+ }
+
+ if (md->ima.active_table.hash) {
+ memcpy(device_table_data + l, active_table_str, active_table_len);
+ l += active_table_len;
+
+ memcpy(device_table_data + l, md->ima.active_table.hash,
+ md->ima.active_table.hash_len);
+ l += md->ima.active_table.hash_len;
+
+ memcpy(device_table_data + l, ",", 1);
+ l++;
+
+ nodata = false;
+ }
+
+ if (md->ima.inactive_table.hash) {
+ memcpy(device_table_data + l, inactive_table_str, inactive_table_len);
+ l += inactive_table_len;
+
+ memcpy(device_table_data + l, md->ima.inactive_table.hash,
+ md->ima.inactive_table.hash_len);
+ l += md->ima.inactive_table.hash_len;
+
+ memcpy(device_table_data + l, ",", 1);
+ l++;
+
+ nodata = false;
+ }
+ /*
+ * In case both active and inactive tables, and corresponding
+ * device metadata is cleared/missing - record the name and uuid
+ * in IMA measurements.
+ */
+ if (nodata) {
+ if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
+ goto error;
+
+ scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
+ "%sname=%s,uuid=%s;device_remove=no_data;",
+ DM_IMA_VERSION_STR, dev_name, dev_uuid);
+ l += strlen(device_table_data);
+ }
+
+ memcpy(device_table_data + l, remove_all_str, remove_all_len);
+ l += remove_all_len;
+ memcpy(device_table_data + l, remove_all ? "y;" : "n;", 2);
+ l += 2;
+
+ capacity_len = strlen(capacity_str);
+ memcpy(device_table_data + l, capacity_str, capacity_len);
+ l += capacity_len;
+
+ dm_ima_measure_data("dm_device_remove", device_table_data, l, noio);
+
+error:
+ kfree(device_table_data);
+ kfree(capacity_str);
+exit:
+ kfree(md->ima.active_table.device_metadata);
+
+ if (md->ima.active_table.device_metadata !=
+ md->ima.inactive_table.device_metadata)
+ kfree(md->ima.inactive_table.device_metadata);
+
+ kfree(md->ima.active_table.hash);
+
+ if (md->ima.active_table.hash != md->ima.inactive_table.hash)
+ kfree(md->ima.inactive_table.hash);
+
+ dm_ima_reset_data(md);
+
+ kfree(dev_name);
+ kfree(dev_uuid);
+}
+
+/*
+ * Measure ima data on table clear.
+ */
+void dm_ima_measure_on_table_clear(struct mapped_device *md, bool new_map)
+{
+ unsigned int l = 0, capacity_len = 0;
+ char *device_table_data = NULL, *dev_name = NULL, *dev_uuid = NULL, *capacity_str = NULL;
+ char inactive_str[] = "inactive_table_hash=";
+ unsigned int inactive_len = strlen(inactive_str);
+ bool noio = true;
+ bool nodata = true;
+ int r;
+
+ device_table_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN, GFP_KERNEL, noio);
+ if (!device_table_data)
+ return;
+
+ r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+ if (r)
+ goto error1;
+
+ memcpy(device_table_data + l, DM_IMA_VERSION_STR, md->ima.dm_version_str_len);
+ l += md->ima.dm_version_str_len;
+
+ if (md->ima.inactive_table.device_metadata_len &&
+ md->ima.inactive_table.hash_len) {
+ memcpy(device_table_data + l, md->ima.inactive_table.device_metadata,
+ md->ima.inactive_table.device_metadata_len);
+ l += md->ima.inactive_table.device_metadata_len;
+
+ memcpy(device_table_data + l, inactive_str, inactive_len);
+ l += inactive_len;
+
+ memcpy(device_table_data + l, md->ima.inactive_table.hash,
+ md->ima.inactive_table.hash_len);
+
+ l += md->ima.inactive_table.hash_len;
+
+ memcpy(device_table_data + l, ";", 1);
+ l++;
+
+ nodata = false;
+ }
+
+ if (nodata) {
+ if (dm_ima_alloc_and_copy_name_uuid(md, &dev_name, &dev_uuid, noio))
+ goto error2;
+
+ scnprintf(device_table_data, DM_IMA_DEVICE_BUF_LEN,
+ "%sname=%s,uuid=%s;table_clear=no_data;",
+ DM_IMA_VERSION_STR, dev_name, dev_uuid);
+ l += strlen(device_table_data);
+ }
+
+ capacity_len = strlen(capacity_str);
+ memcpy(device_table_data + l, capacity_str, capacity_len);
+ l += capacity_len;
+
+ dm_ima_measure_data("dm_table_clear", device_table_data, l, noio);
+
+ if (new_map) {
+ if (md->ima.inactive_table.hash &&
+ md->ima.inactive_table.hash != md->ima.active_table.hash)
+ kfree(md->ima.inactive_table.hash);
+
+ md->ima.inactive_table.hash = NULL;
+ md->ima.inactive_table.hash_len = 0;
+
+ if (md->ima.inactive_table.device_metadata &&
+ md->ima.inactive_table.device_metadata != md->ima.active_table.device_metadata)
+ kfree(md->ima.inactive_table.device_metadata);
+
+ md->ima.inactive_table.device_metadata = NULL;
+ md->ima.inactive_table.device_metadata_len = 0;
+ md->ima.inactive_table.num_targets = 0;
+
+ if (md->ima.active_table.hash) {
+ md->ima.inactive_table.hash = md->ima.active_table.hash;
+ md->ima.inactive_table.hash_len = md->ima.active_table.hash_len;
+ }
+
+ if (md->ima.active_table.device_metadata) {
+ md->ima.inactive_table.device_metadata =
+ md->ima.active_table.device_metadata;
+ md->ima.inactive_table.device_metadata_len =
+ md->ima.active_table.device_metadata_len;
+ md->ima.inactive_table.num_targets =
+ md->ima.active_table.num_targets;
+ }
+ }
+
+ kfree(dev_name);
+ kfree(dev_uuid);
+error2:
+ kfree(capacity_str);
+error1:
+ kfree(device_table_data);
+}
+
+/*
+ * Measure IMA data on device rename.
+ */
+void dm_ima_measure_on_device_rename(struct mapped_device *md)
+{
+ char *old_device_data = NULL, *new_device_data = NULL, *combined_device_data = NULL;
+ char *new_dev_name = NULL, *new_dev_uuid = NULL, *capacity_str = NULL;
+ bool noio = true;
+ int r;
+
+ if (dm_ima_alloc_and_copy_device_data(md, &new_device_data,
+ md->ima.active_table.num_targets, noio))
+ return;
+
+ if (dm_ima_alloc_and_copy_name_uuid(md, &new_dev_name, &new_dev_uuid, noio))
+ goto error;
+
+ combined_device_data = dm_ima_alloc(DM_IMA_DEVICE_BUF_LEN * 2, GFP_KERNEL, noio);
+ if (!combined_device_data)
+ goto error;
+
+ r = dm_ima_alloc_and_copy_capacity_str(md, &capacity_str, noio);
+ if (r)
+ goto error;
+
+ old_device_data = md->ima.active_table.device_metadata;
+
+ md->ima.active_table.device_metadata = new_device_data;
+ md->ima.active_table.device_metadata_len = strlen(new_device_data);
+
+ scnprintf(combined_device_data, DM_IMA_DEVICE_BUF_LEN * 2,
+ "%s%snew_name=%s,new_uuid=%s;%s", DM_IMA_VERSION_STR, old_device_data,
+ new_dev_name, new_dev_uuid, capacity_str);
+
+ dm_ima_measure_data("dm_device_rename", combined_device_data, strlen(combined_device_data),
+ noio);
+
+ goto exit;
+
+error:
+ kfree(new_device_data);
+exit:
+ kfree(capacity_str);
+ kfree(combined_device_data);
+ kfree(old_device_data);
+ kfree(new_dev_name);
+ kfree(new_dev_uuid);
+}
int ima_appraise;
#endif
- int ima_hash_algo = HASH_ALGO_SHA1;
+ int __ro_after_init ima_hash_algo = HASH_ALGO_SHA1;
static int hash_setup_done;
static struct notifier_block ima_lsm_policy_notifier = {
}
__setup("ima_hash=", hash_setup);
+ enum hash_algo ima_get_current_hash_algo(void)
+ {
+ return ima_hash_algo;
+ }
+
/* Prevent mmap'ing a file execute that is already mmap'ed write */
static int mmap_violation_check(enum ima_hooks func, struct file *file,
char **pathbuf, const char **pathname,
int xattr_len = 0;
bool violation_check;
enum hash_algo hash_algo;
+ unsigned int allowed_algos = 0;
if (!ima_policy_flag || !S_ISREG(inode->i_mode))
return 0;
* Included is the appraise submask.
*/
action = ima_get_action(file_mnt_user_ns(file), inode, cred, secid,
- mask, func, &pcr, &template_desc, NULL);
+ mask, func, &pcr, &template_desc, NULL,
+ &allowed_algos);
violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) &&
(ima_policy_flag & IMA_MEASURE));
if (!action && !violation_check)
if ((file->f_flags & O_DIRECT) && (iint->flags & IMA_PERMIT_DIRECTIO))
rc = 0;
+
+ /* Ensure the digest was generated using an allowed algorithm */
+ if (rc == 0 && must_appraise && allowed_algos != 0 &&
+ (allowed_algos & (1U << hash_algo)) == 0) {
+ rc = -EACCES;
+
+ integrity_audit_msg(AUDIT_INTEGRITY_DATA, file_inode(file),
+ pathname, "collect_data",
+ "denied-hash-algorithm", rc, 0);
+ }
out_locked:
if ((mask & MAY_WRITE) && test_bit(IMA_DIGSIG, &iint->atomic_flags) &&
!(iint->flags & IMA_NEW_FILE))
inode = file_inode(vma->vm_file);
action = ima_get_action(file_mnt_user_ns(vma->vm_file), inode,
current_cred(), secid, MAY_EXEC, MMAP_CHECK,
- &pcr, &template, NULL);
+ &pcr, &template, NULL, NULL);
/* Is the mmap'ed file in policy? */
if (!(action & (IMA_MEASURE | IMA_APPRAISE_SUBMASK)))
return 0;
}
- /*
+ /**
* process_buffer_measurement - Measure the buffer or the buffer data hash
* @mnt_userns: user namespace of the mount the inode was found from
* @inode: inode associated with the object being measured (NULL for KEY_CHECK)
* @pcr: pcr to extend the measurement
* @func_data: func specific data, may be NULL
* @buf_hash: measure buffer data hash
+ * @digest: buffer digest will be written to
+ * @digest_len: buffer length
*
* Based on policy, either the buffer data or buffer data hash is measured
+ *
+ * Return: 0 if the buffer has been successfully measured, 1 if the digest
+ * has been written to the passed location but not added to a measurement entry,
+ * a negative value otherwise.
*/
- void process_buffer_measurement(struct user_namespace *mnt_userns,
- struct inode *inode, const void *buf, int size,
- const char *eventname, enum ima_hooks func,
- int pcr, const char *func_data,
- bool buf_hash)
+ int process_buffer_measurement(struct user_namespace *mnt_userns,
+ struct inode *inode, const void *buf, int size,
+ const char *eventname, enum ima_hooks func,
+ int pcr, const char *func_data,
+ bool buf_hash, u8 *digest, size_t digest_len)
{
int ret = 0;
const char *audit_cause = "ENOMEM";
int action = 0;
u32 secid;
- if (!ima_policy_flag)
- return;
+ if (digest && digest_len < digest_hash_len)
+ return -EINVAL;
+
+ if (!ima_policy_flag && !digest)
+ return -ENOENT;
template = ima_template_desc_buf();
if (!template) {
security_task_getsecid_subj(current, &secid);
action = ima_get_action(mnt_userns, inode, current_cred(),
secid, 0, func, &pcr, &template,
- func_data);
- if (!(action & IMA_MEASURE))
- return;
+ func_data, NULL);
+ if (!(action & IMA_MEASURE) && !digest)
+ return -ENOENT;
}
if (!pcr)
event_data.buf_len = digest_hash_len;
}
+ if (digest)
+ memcpy(digest, iint.ima_hash->digest, digest_hash_len);
+
+ if (!ima_policy_flag || (func && !(action & IMA_MEASURE)))
+ return 1;
+
ret = ima_alloc_init_template(&event_data, &entry, template);
if (ret < 0) {
audit_cause = "alloc_entry";
func_measure_str(func),
audit_cause, ret, 0, ret);
- return;
+ return ret;
}
/**
process_buffer_measurement(file_mnt_user_ns(f.file), file_inode(f.file),
buf, size, "kexec-cmdline", KEXEC_CMDLINE, 0,
- NULL, false);
+ NULL, false, NULL, 0);
fdput(f);
}
* @buf: pointer to buffer data
* @buf_len: length of buffer data (in bytes)
* @hash: measure buffer data hash
+ * @digest: buffer digest will be written to
+ * @digest_len: buffer length
*
* Measure data critical to the integrity of the kernel into the IMA log
* and extend the pcr. Examples of critical data could be various data
* structures, policies, and states stored in kernel memory that can
* impact the integrity of the system.
+ *
+ * Return: 0 if the buffer has been successfully measured, 1 if the digest
+ * has been written to the passed location but not added to a measurement entry,
+ * a negative value otherwise.
*/
- void ima_measure_critical_data(const char *event_label,
- const char *event_name,
- const void *buf, size_t buf_len,
- bool hash)
+ int ima_measure_critical_data(const char *event_label,
+ const char *event_name,
+ const void *buf, size_t buf_len,
+ bool hash, u8 *digest, size_t digest_len)
{
if (!event_name || !event_label || !buf || !buf_len)
- return;
+ return -ENOPARAM;
- process_buffer_measurement(&init_user_ns, NULL, buf, buf_len, event_name,
- CRITICAL_DATA, 0, event_label,
- hash);
+ return process_buffer_measurement(&init_user_ns, NULL, buf, buf_len,
+ event_name, CRITICAL_DATA, 0,
+ event_label, hash, digest,
+ digest_len);
}
+EXPORT_SYMBOL_GPL(ima_measure_critical_data);
static int __init init_ima(void)
{
pr_warn("Couldn't register LSM notifier, error %d\n", error);
if (!error)
- ima_update_policy_flag();
+ ima_update_policy_flags();
return error;
}
projects / linux-2.6-microblaze.git / commitdiff