From: Johannes Berg <johannes.berg@xxxxxxxxx>
As the current regulatory database is only about 4k big, and already
difficult to extend, we decided that overall it would be better to
get rid of the complications with CRDA and load the database into the
kernel directly, but in a new format that is extensible.
The new file format can be extended since it carries a length field
on all the structs that need to be extensible.
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
---
Documentation/networking/regulatory.txt | 8 +
net/wireless/Kconfig | 3 +-
net/wireless/reg.c | 260 +++++++++++++++++++++++++++++---
3 files changed, 248 insertions(+), 23 deletions(-)
diff --git a/Documentation/networking/regulatory.txt b/Documentation/networking/regulatory.txt
index 356f791af574..753f912185eb 100644
--- a/Documentation/networking/regulatory.txt
+++ b/Documentation/networking/regulatory.txt
@@ -19,6 +19,14 @@ core regulatory domain all wireless devices should adhere to.
How to get regulatory domains to the kernel
-------------------------------------------
+When the regulatory domain is first set up, the kernel will request a
+database file (regulatory.db) containing all the regulatory rules. It
+will then use that database when it needs to look up the rules for a
+given country.
+
+How to get regulatory domains to the kernel (old CRDA solution)
+---------------------------------------------------------------
+
Userspace gets a regulatory domain in the kernel by having
a userspace agent build it and send it via nl80211. Only
expected regulatory domains will be respected by the kernel.
diff --git a/net/wireless/Kconfig b/net/wireless/Kconfig
index ab7017951083..063b29f15a70 100644
--- a/net/wireless/Kconfig
+++ b/net/wireless/Kconfig
@@ -180,7 +180,8 @@ config CFG80211_CRDA_SUPPORT
depends on CFG80211
help
You should enable this option unless you know for sure you have no
- need for it, for example when using internal regdb (above.)
+ need for it, for example when using internal regdb (above) or the
+ database loaded as a firmware file.
If unsure, say Y.
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index c8f43a8f850b..82b394bddfc3 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -53,6 +53,7 @@
#include <linux/nl80211.h>
#include <linux/platform_device.h>
#include <linux/moduleparam.h>
+#include <linux/firmware.h>
#include <net/cfg80211.h>
#include "core.h"
#include "reg.h"
@@ -106,7 +107,7 @@ static struct regulatory_request core_request_world = {
static struct regulatory_request __rcu *last_request =
(void __force __rcu *)&core_request_world;
-/* To trigger userspace events */
+/* To trigger userspace events and load firmware */
static struct platform_device *reg_pdev;
/*
@@ -449,7 +450,6 @@ reg_copy_regd(const struct ieee80211_regdomain *src_regd)
return regd;
}
-#ifdef CONFIG_CFG80211_INTERNAL_REGDB
struct reg_regdb_apply_request {
struct list_head list;
const struct ieee80211_regdomain *regdom;
@@ -481,41 +481,44 @@ static void reg_regdb_apply(struct work_struct *work)
static DECLARE_WORK(reg_regdb_work, reg_regdb_apply);
-static int reg_query_builtin(const char *alpha2)
+static int reg_schedule_apply(const struct ieee80211_regdomain *regdom)
{
- const struct ieee80211_regdomain *regdom = NULL;
struct reg_regdb_apply_request *request;
- unsigned int i;
-
- for (i = 0; i < reg_regdb_size; i++) {
- if (alpha2_equal(alpha2, reg_regdb[i]->alpha2)) {
- regdom = reg_regdb[i];
- break;
- }
- }
-
- if (!regdom)
- return -ENODATA;
request = kzalloc(sizeof(struct reg_regdb_apply_request), GFP_KERNEL);
- if (!request)
- return -ENOMEM;
-
- request->regdom = reg_copy_regd(regdom);
- if (IS_ERR_OR_NULL(request->regdom)) {
- kfree(request);
+ if (!request) {
+ kfree(regdom);
return -ENOMEM;
}
+ request->regdom = regdom;
+
mutex_lock(®_regdb_apply_mutex);
list_add_tail(&request->list, ®_regdb_apply_list);
mutex_unlock(®_regdb_apply_mutex);
schedule_work(®_regdb_work);
-
return 0;
}
+#ifdef CONFIG_CFG80211_INTERNAL_REGDB
+static int reg_query_builtin(const char *alpha2)
+{
+ const struct ieee80211_regdomain *regdom = NULL;
+ unsigned int i;
+
+ for (i = 0; i < reg_regdb_size; i++) {
+ if (alpha2_equal(alpha2, reg_regdb[i]->alpha2)) {
+ regdom = reg_copy_regd(reg_regdb[i]);
+ break;
+ }
+ }
+ if (!regdom)
+ return -ENODATA;
+
+ return reg_schedule_apply(regdom);
+}
+
/* Feel free to add any other sanity checks here */
static void reg_regdb_size_check(void)
{
@@ -605,12 +608,222 @@ static inline int call_crda(const char *alpha2)
}
#endif /* CONFIG_CFG80211_CRDA_SUPPORT */
+/* code to directly load a firmware database through request_firmware */
+static const struct firmware *regdb;
+static unsigned int fwregdb_attempts = 10;
+
+struct fwdb_country {
+ u8 alpha2[2];
+ __be16 coll_ptr;
+} __packed __aligned(4);
+
+struct fwdb_collection {
+ __be16 len;
+ __be16 n_rules;
+ u8 dfs_region;
+ u8 pad_reserved;
+ __be16 rules_ptr[];
+} __packed __aligned(4);
+
+struct fwdb_rule {
+ __be16 len;
+ __be16 flags;
+ __be32 start, end, max_bw;
+ __be32 cac_timeout;
+ __be16 max_ant_gain;
+ __be16 max_eirp;
+} __packed __aligned(4);
+
+#define FWDB_MAGIC 0x52474442
+#define FWDB_VERSION 20
+
+struct fwdb_header {
+ __be32 magic;
+ __be32 version;
+ struct fwdb_country country[];
+} __packed __aligned(4);
+
+static bool valid_rule(const struct firmware *db, u16 rule_ptr)
+{
+ struct fwdb_rule *rule = (void *)(db->data + (rule_ptr << 2));
+
+ if ((u8 *)rule + sizeof(rule->len) > db->data + db->size)
+ return false;
+
+ /* mandatory fields */
+ if (be16_to_cpu(rule->len) < 24)
+ return false;
+
+ return true;
+}
+
+static bool valid_country(const struct firmware *db,
+ const struct fwdb_country *country)
+{
+ unsigned int ptr = be16_to_cpu(country->coll_ptr) << 2;
+ struct fwdb_collection *coll = (void *)(db->data + ptr);
+ unsigned int i;
+
+ if ((u8 *)coll + sizeof(coll->len) > db->data + db->size)
+ return false;
+
+ if ((u8 *)coll + be16_to_cpu(coll->len) > db->data + db->size)
+ return false;
+
+ /* mandatory fields */
+ if (be16_to_cpu(coll->len) < 6)
+ return false;
+
+ if (be16_to_cpu(coll->len) < 6 + 2 * be16_to_cpu(coll->n_rules))
+ return false;
+
+ for (i = 0; i < be16_to_cpu(coll->n_rules); i++) {
+ u16 rule_ptr = be16_to_cpu(coll->rules_ptr[i]);
+
+ if (!valid_rule(db, rule_ptr))
+ return false;
+ }
+
+ return true;
+}
+
+static bool valid_regdb(const struct firmware *db)
+{
+ const struct fwdb_header *hdr = (void *)db->data;
+ const struct fwdb_country *country;
+
+ if (db->size < sizeof(*hdr))
+ return false;
+
+ if (hdr->magic != cpu_to_be32(FWDB_MAGIC))
+ return false;
+
+ if (hdr->version != cpu_to_be32(FWDB_VERSION))
+ return false;
+
+ country = &hdr->country[0];
+ while ((u8 *)(country + 1) <= db->data + db->size) {
+ if (!country->coll_ptr)
+ break;
+ if (!valid_country(db, country))
+ return false;
+ country++;
+ }
+
+ return true;
+}
+
+static int regdb_query_country(const struct firmware *db,
+ const struct fwdb_country *country)
+{
+ unsigned int ptr = be16_to_cpu(country->coll_ptr) << 2;
+ struct fwdb_collection *coll = (void *)(db->data + ptr);
+ struct ieee80211_regdomain *regdom;
+ unsigned int size_of_regd;
+ unsigned int i;
+
+ size_of_regd =
+ sizeof(struct ieee80211_regdomain) +
+ be16_to_cpu(coll->n_rules) * sizeof(struct ieee80211_reg_rule);
+
+ regdom = kzalloc(size_of_regd, GFP_KERNEL);
+ if (!regdom)
+ return -ENOMEM;
+
+ regdom->n_reg_rules = be16_to_cpu(coll->n_rules);
+ regdom->alpha2[0] = country->alpha2[0];
+ regdom->alpha2[1] = country->alpha2[1];
+ regdom->dfs_region = coll->dfs_region;
+
+ for (i = 0; i < regdom->n_reg_rules; i++) {
+ unsigned int rule_ptr = be16_to_cpu(coll->rules_ptr[i]) << 2;
+ struct fwdb_rule *rule = (void *)(db->data + rule_ptr);
+ struct ieee80211_reg_rule *rrule = ®dom->reg_rules[i];
+
+ rrule->freq_range.start_freq_khz = be32_to_cpu(rule->start);
+ rrule->freq_range.end_freq_khz = be32_to_cpu(rule->end);
+ rrule->freq_range.max_bandwidth_khz = be32_to_cpu(rule->max_bw);
+
+ rrule->power_rule.max_antenna_gain =
+ be16_to_cpu(rule->max_ant_gain);
+ rrule->power_rule.max_eirp = be16_to_cpu(rule->max_eirp);
+
+ rrule->flags = be16_to_cpu(rule->flags);
+ rrule->dfs_cac_ms = be32_to_cpu(rule->cac_timeout);
+ }
+
+ return reg_schedule_apply(regdom);
+}
+
+static int query_regdb(const char *alpha2)
+{
+ const struct fwdb_header *hdr;
+ const struct fwdb_country *country;
+
+ if (IS_ERR(regdb))
+ return PTR_ERR(regdb);
+
+ hdr = (void *)regdb->data;
+ country = &hdr->country[0];
+ while (country->coll_ptr) {
+ if (alpha2_equal(alpha2, country->alpha2))
+ return regdb_query_country(regdb, country);
+ country++;
+ }
+
+ return -ENODATA;
+}
+
+static void regdb_fw_cb(const struct firmware *fw, void *context)
+{
+ if (!fw) {
+ pr_info("failed to load regulatory.db\n");
+ if (fwregdb_attempts-- == 0)
+ regdb = ERR_PTR(-ENODATA);
+ goto restore;
+ }
+
+ if (!valid_regdb(fw)) {
+ release_firmware(fw);
+ regdb = ERR_PTR(-EINVAL);
+ goto restore;
+ }
+
+ regdb = fw;
+ if (query_regdb(context))
+ goto restore;
+ goto free;
+ restore:
+ rtnl_lock();
+ restore_regulatory_settings(true);
+ rtnl_unlock();
+ free:
+ kfree(context);
+}
+
+static int query_regdb_file(const char *alpha2)
+{
+ if (regdb)
+ return query_regdb(alpha2);
+
+ alpha2 = kmemdup(alpha2, 2, GFP_KERNEL);
+ if (!alpha2)
+ return -ENOMEM;
+
+ return request_firmware_nowait(THIS_MODULE, true, "regulatory.db",
+ ®_pdev->dev, GFP_KERNEL,
+ (void *)alpha2, regdb_fw_cb);
+}
+
static bool reg_query_database(struct regulatory_request *request)
{
/* query internal regulatory database (if it exists) */
if (reg_query_builtin(request->alpha2) == 0)
return true;
+ if (query_regdb_file(request->alpha2) == 0)
+ return true;
+
if (call_crda(request->alpha2) == 0)
return true;
@@ -3276,4 +3489,7 @@ void regulatory_exit(void)
list_del(®_request->list);
kfree(reg_request);
}
+
+ if (!IS_ERR_OR_NULL(regdb))
+ release_firmware(regdb);
}
--
2.5.1
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