1 files changed, 120 insertions, 1 deletions

diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index ebf8267ffbc9..58319c82ecb3 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -53,6 +53,7 @@
 #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>
@@ -659,6 +660,115 @@ static bool valid_country(const u8 *data, unsigned int size,
 	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", &reg_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;
@@ -673,6 +783,9 @@ static bool valid_regdb(const u8 *data, unsigned int size)
 	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)
@@ -773,7 +886,7 @@ static void regdb_fw_cb(const struct firmware *fw, void *context)
 		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\n");
+		pr_info("loaded regulatory.db is malformed or signature is missing/invalid\n");
 		set_error = -EINVAL;
 	}
 
@@ -3535,6 +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);
@@ -3611,4 +3728,6 @@ void regulatory_exit(void)
 
 	if (!IS_ERR_OR_NULL(regdb))
 		kfree(regdb);
+
+	free_regdb_keyring();
 }