diff options
Diffstat (limited to 'net/wireless/reg.c')
-rw-r--r-- | net/wireless/reg.c | 452 |
1 files changed, 411 insertions, 41 deletions
diff --git a/net/wireless/reg.c b/net/wireless/reg.c index 6e94f6934a0e..58319c82ecb3 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -53,12 +53,13 @@ #include <linux/ctype.h> #include <linux/nl80211.h> #include <linux/platform_device.h> +#include <linux/verification.h> #include <linux/moduleparam.h> +#include <linux/firmware.h> #include <net/cfg80211.h> #include "core.h" #include "reg.h" #include "rdev-ops.h" -#include "regdb.h" #include "nl80211.h" /* @@ -100,7 +101,7 @@ 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; /* @@ -443,7 +444,6 @@ 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; @@ -475,55 +475,26 @@ 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; } -/* Feel free to add any other sanity checks here */ -static void reg_regdb_size_check(void) -{ - /* We should ideally BUILD_BUG_ON() but then random builds would fail */ - WARN_ONCE(!reg_regdb_size, "db.txt is empty, you should update it..."); -} -#else -static inline void reg_regdb_size_check(void) {} -static inline int reg_query_builtin(const char *alpha2) -{ - return -ENODATA; -} -#endif /* CONFIG_CFG80211_INTERNAL_REGDB */ - #ifdef CONFIG_CFG80211_CRDA_SUPPORT /* Max number of consecutive attempts to communicate with CRDA */ #define REG_MAX_CRDA_TIMEOUTS 10 @@ -599,10 +570,402 @@ 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 fwdb_header *regdb; + +struct fwdb_country { + u8 alpha2[2]; + __be16 coll_ptr; + /* this struct cannot be extended */ +} __packed __aligned(4); + +struct fwdb_collection { + u8 len; + u8 n_rules; + u8 dfs_region; + /* no optional data yet */ + /* aligned to 2, then followed by __be16 array of rule pointers */ +} __packed __aligned(4); + +enum fwdb_flags { + FWDB_FLAG_NO_OFDM = BIT(0), + FWDB_FLAG_NO_OUTDOOR = BIT(1), + FWDB_FLAG_DFS = BIT(2), + FWDB_FLAG_NO_IR = BIT(3), + FWDB_FLAG_AUTO_BW = BIT(4), +}; + +struct fwdb_rule { + u8 len; + u8 flags; + __be16 max_eirp; + __be32 start, end, max_bw; + /* start of optional data */ + __be16 cac_timeout; +} __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 u8 *data, unsigned int size, u16 rule_ptr) +{ + struct fwdb_rule *rule = (void *)(data + (rule_ptr << 2)); + + if ((u8 *)rule + sizeof(rule->len) > data + size) + return false; + + /* mandatory fields */ + if (rule->len < offsetofend(struct fwdb_rule, max_bw)) + return false; + + return true; +} + +static bool valid_country(const u8 *data, unsigned int size, + const struct fwdb_country *country) +{ + unsigned int ptr = be16_to_cpu(country->coll_ptr) << 2; + struct fwdb_collection *coll = (void *)(data + ptr); + __be16 *rules_ptr; + unsigned int i; + + /* make sure we can read len/n_rules */ + if ((u8 *)coll + offsetofend(typeof(*coll), n_rules) > data + size) + return false; + + /* make sure base struct and all rules fit */ + if ((u8 *)coll + ALIGN(coll->len, 2) + + (coll->n_rules * 2) > data + size) + return false; + + /* mandatory fields must exist */ + if (coll->len < offsetofend(struct fwdb_collection, dfs_region)) + return false; + + rules_ptr = (void *)((u8 *)coll + ALIGN(coll->len, 2)); + + for (i = 0; i < coll->n_rules; i++) { + u16 rule_ptr = be16_to_cpu(rules_ptr[i]); + + if (!valid_rule(data, size, rule_ptr)) + return false; + } + + return true; +} + +#ifdef CONFIG_CFG80211_REQUIRE_SIGNED_REGDB +static struct key *builtin_regdb_keys; + +static void __init load_keys_from_buffer(const u8 *p, unsigned int buflen) +{ + const u8 *end = p + buflen; + size_t plen; + key_ref_t key; + + while (p < end) { + /* Each cert begins with an ASN.1 SEQUENCE tag and must be more + * than 256 bytes in size. + */ + if (end - p < 4) + goto dodgy_cert; + if (p[0] != 0x30 && + p[1] != 0x82) + goto dodgy_cert; + plen = (p[2] << 8) | p[3]; + plen += 4; + if (plen > end - p) + goto dodgy_cert; + + key = key_create_or_update(make_key_ref(builtin_regdb_keys, 1), + "asymmetric", NULL, p, plen, + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ), + KEY_ALLOC_NOT_IN_QUOTA | + KEY_ALLOC_BUILT_IN | + KEY_ALLOC_BYPASS_RESTRICTION); + if (IS_ERR(key)) { + pr_err("Problem loading in-kernel X.509 certificate (%ld)\n", + PTR_ERR(key)); + } else { + pr_notice("Loaded X.509 cert '%s'\n", + key_ref_to_ptr(key)->description); + key_ref_put(key); + } + p += plen; + } + + return; + +dodgy_cert: + pr_err("Problem parsing in-kernel X.509 certificate list\n"); +} + +static int __init load_builtin_regdb_keys(void) +{ + builtin_regdb_keys = + keyring_alloc(".builtin_regdb_keys", + KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH), + KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); + if (IS_ERR(builtin_regdb_keys)) + return PTR_ERR(builtin_regdb_keys); + + pr_notice("Loading compiled-in X.509 certificates for regulatory database\n"); + +#ifdef CONFIG_CFG80211_USE_KERNEL_REGDB_KEYS + load_keys_from_buffer(shipped_regdb_certs, shipped_regdb_certs_len); +#endif +#ifdef CFG80211_EXTRA_REGDB_KEYDIR + if (CONFIG_CFG80211_EXTRA_REGDB_KEYDIR[0] != '\0') + load_keys_from_buffer(extra_regdb_certs, extra_regdb_certs_len); +#endif + + return 0; +} + +static bool regdb_has_valid_signature(const u8 *data, unsigned int size) +{ + const struct firmware *sig; + bool result; + + if (request_firmware(&sig, "regulatory.db.p7s", ®_pdev->dev)) + return false; + + result = verify_pkcs7_signature(data, size, sig->data, sig->size, + builtin_regdb_keys, + VERIFYING_UNSPECIFIED_SIGNATURE, + NULL, NULL) == 0; + + release_firmware(sig); + + return result; +} + +static void free_regdb_keyring(void) +{ + key_put(builtin_regdb_keys); +} +#else +static int load_builtin_regdb_keys(void) +{ + return 0; +} + +static bool regdb_has_valid_signature(const u8 *data, unsigned int size) +{ + return true; +} + +static void free_regdb_keyring(void) +{ +} +#endif /* CONFIG_CFG80211_REQUIRE_SIGNED_REGDB */ + +static bool valid_regdb(const u8 *data, unsigned int size) +{ + const struct fwdb_header *hdr = (void *)data; + const struct fwdb_country *country; + + if (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; + + if (!regdb_has_valid_signature(data, size)) + return false; + + country = &hdr->country[0]; + while ((u8 *)(country + 1) <= data + size) { + if (!country->coll_ptr) + break; + if (!valid_country(data, size, country)) + return false; + country++; + } + + return true; +} + +static int regdb_query_country(const struct fwdb_header *db, + const struct fwdb_country *country) +{ + unsigned int ptr = be16_to_cpu(country->coll_ptr) << 2; + struct fwdb_collection *coll = (void *)((u8 *)db + ptr); + struct ieee80211_regdomain *regdom; + unsigned int size_of_regd; + unsigned int i; + + size_of_regd = + sizeof(struct ieee80211_regdomain) + + coll->n_rules * sizeof(struct ieee80211_reg_rule); + + regdom = kzalloc(size_of_regd, GFP_KERNEL); + if (!regdom) + return -ENOMEM; + + regdom->n_reg_rules = 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++) { + __be16 *rules_ptr = (void *)((u8 *)coll + ALIGN(coll->len, 2)); + unsigned int rule_ptr = be16_to_cpu(rules_ptr[i]) << 2; + struct fwdb_rule *rule = (void *)((u8 *)db + 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 = 0; + rrule->power_rule.max_eirp = be16_to_cpu(rule->max_eirp); + + rrule->flags = 0; + if (rule->flags & FWDB_FLAG_NO_OFDM) + rrule->flags |= NL80211_RRF_NO_OFDM; + if (rule->flags & FWDB_FLAG_NO_OUTDOOR) + rrule->flags |= NL80211_RRF_NO_OUTDOOR; + if (rule->flags & FWDB_FLAG_DFS) + rrule->flags |= NL80211_RRF_DFS; + if (rule->flags & FWDB_FLAG_NO_IR) + rrule->flags |= NL80211_RRF_NO_IR; + if (rule->flags & FWDB_FLAG_AUTO_BW) + rrule->flags |= NL80211_RRF_AUTO_BW; + + rrule->dfs_cac_ms = 0; + + /* handle optional data */ + if (rule->len >= offsetofend(struct fwdb_rule, cac_timeout)) + rrule->dfs_cac_ms = + 1000 * be16_to_cpu(rule->cac_timeout); + } + + return reg_schedule_apply(regdom); +} + +static int query_regdb(const char *alpha2) +{ + const struct fwdb_header *hdr = regdb; + const struct fwdb_country *country; + + ASSERT_RTNL(); + + if (IS_ERR(regdb)) + return PTR_ERR(regdb); + + 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) +{ + int set_error = 0; + bool restore = true; + void *db; + + if (!fw) { + pr_info("failed to load regulatory.db\n"); + set_error = -ENODATA; + } else if (!valid_regdb(fw->data, fw->size)) { + pr_info("loaded regulatory.db is malformed or signature is missing/invalid\n"); + set_error = -EINVAL; + } + + rtnl_lock(); + if (WARN_ON(regdb && !IS_ERR(regdb))) { + /* just restore and free new db */ + } else if (set_error) { + regdb = ERR_PTR(set_error); + } else if (fw) { + db = kmemdup(fw->data, fw->size, GFP_KERNEL); + if (db) { + regdb = db; + restore = context && query_regdb(context); + } else { + restore = true; + } + } + + if (restore) + restore_regulatory_settings(true); + + rtnl_unlock(); + + kfree(context); + + release_firmware(fw); +} + +static int query_regdb_file(const char *alpha2) +{ + ASSERT_RTNL(); + + 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); +} + +int reg_reload_regdb(void) +{ + const struct firmware *fw; + void *db; + int err; + + err = request_firmware(&fw, "regulatory.db", ®_pdev->dev); + if (err) + return err; + + if (!valid_regdb(fw->data, fw->size)) { + err = -ENODATA; + goto out; + } + + db = kmemdup(fw->data, fw->size, GFP_KERNEL); + if (!db) { + err = -ENOMEM; + goto out; + } + + rtnl_lock(); + if (!IS_ERR_OR_NULL(regdb)) + kfree(regdb); + regdb = db; + rtnl_unlock(); + + out: + release_firmware(fw); + return err; +} + static bool reg_query_database(struct regulatory_request *request) { - /* query internal regulatory database (if it exists) */ - if (reg_query_builtin(request->alpha2) == 0) + if (query_regdb_file(request->alpha2) == 0) return true; if (call_crda(request->alpha2) == 0) @@ -3285,6 +3648,10 @@ int __init regulatory_init(void) { int err = 0; + err = load_builtin_regdb_keys(); + if (err) + return err; + reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0); if (IS_ERR(reg_pdev)) return PTR_ERR(reg_pdev); @@ -3293,8 +3660,6 @@ int __init regulatory_init(void) spin_lock_init(®_pending_beacons_lock); spin_lock_init(®_indoor_lock); - reg_regdb_size_check(); - rcu_assign_pointer(cfg80211_regdomain, cfg80211_world_regdom); user_alpha2[0] = '9'; @@ -3360,4 +3725,9 @@ void regulatory_exit(void) list_del(®_request->list); kfree(reg_request); } + + if (!IS_ERR_OR_NULL(regdb)) + kfree(regdb); + + free_regdb_keyring(); } |