diff --git a/Documentation/netlink/specs/ovpn.yaml b/Documentation/netlink/specs/ovpn.yaml index b0c782e59a32..43b9ab1eb3da 100644 --- a/Documentation/netlink/specs/ovpn.yaml +++ b/Documentation/netlink/specs/ovpn.yaml @@ -16,6 +16,10 @@ definitions: type: const name: nonce-tail-size value: 8 + - + type: const + name: epoch-prk-size + value: 32 - type: enum name: cipher-alg @@ -274,6 +278,16 @@ attribute-sets: type: nest doc: Key material for decrypt direction nested-attributes: keydir + - + name: encrypt-epoch + type: nest + doc: Epoch PRK material used to derive encrypt data keys + nested-attributes: epoch + - + name: decrypt-epoch + type: nest + doc: Epoch PRK material used to derive decrypt data keys + nested-attributes: epoch - name: keydir attributes: @@ -291,6 +305,23 @@ attribute-sets: obtain the actual cipher IV checks: exact-len: nonce-tail-size + - + name: epoch + attributes: + - + name: key + type: binary + doc: >- + The epoch PRK used to derive cipher keys and implicit IVs + checks: + exact-len: epoch-prk-size + - + name: cipher-key-len + type: u32 + doc: Length in bytes of the AEAD cipher key derived from the epoch PRK + checks: + min: 1 + max: epoch-prk-size - name: keyconf-get diff --git a/drivers/net/ovpn/crypto_epoch.h b/drivers/net/ovpn/crypto_epoch.h index 7da31c2acd44..76278c73eba4 100644 --- a/drivers/net/ovpn/crypto_epoch.h +++ b/drivers/net/ovpn/crypto_epoch.h @@ -16,7 +16,6 @@ #include #include -#define OVPN_EPOCH_PRK_SIZE 32 #define OVPN_MAX_EPOCH U16_MAX #define OVPN_EPOCH_FUTURE_KEYS_COUNT 16 diff --git a/drivers/net/ovpn/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c index 2147cec7c2c5..667a51f52158 100644 --- a/drivers/net/ovpn/netlink-gen.c +++ b/drivers/net/ovpn/netlink-gen.c @@ -25,13 +25,20 @@ static const struct netlink_range_validation ovpn_a_keyconf_peer_id_range = { }; /* Common nested types */ -const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1] = { +const struct nla_policy ovpn_epoch_nl_policy[OVPN_A_EPOCH_CIPHER_KEY_LEN + 1] = { + [OVPN_A_EPOCH_KEY] = NLA_POLICY_EXACT_LEN(OVPN_EPOCH_PRK_SIZE), + [OVPN_A_EPOCH_CIPHER_KEY_LEN] = NLA_POLICY_RANGE(NLA_U32, 1, OVPN_EPOCH_PRK_SIZE), +}; + +const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_EPOCH + 1] = { [OVPN_A_KEYCONF_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_keyconf_peer_id_range), [OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1), [OVPN_A_KEYCONF_KEY_ID] = NLA_POLICY_MAX(NLA_U32, 7), [OVPN_A_KEYCONF_CIPHER_ALG] = NLA_POLICY_MAX(NLA_U32, 2), [OVPN_A_KEYCONF_ENCRYPT_DIR] = NLA_POLICY_NESTED(ovpn_keydir_nl_policy), [OVPN_A_KEYCONF_DECRYPT_DIR] = NLA_POLICY_NESTED(ovpn_keydir_nl_policy), + [OVPN_A_KEYCONF_ENCRYPT_EPOCH] = NLA_POLICY_NESTED(ovpn_epoch_nl_policy), + [OVPN_A_KEYCONF_DECRYPT_EPOCH] = NLA_POLICY_NESTED(ovpn_epoch_nl_policy), }; const struct nla_policy ovpn_keyconf_del_input_nl_policy[OVPN_A_KEYCONF_SLOT + 1] = { diff --git a/drivers/net/ovpn/netlink-gen.h b/drivers/net/ovpn/netlink-gen.h index 67cd85f86173..72f765f574a5 100644 --- a/drivers/net/ovpn/netlink-gen.h +++ b/drivers/net/ovpn/netlink-gen.h @@ -13,7 +13,8 @@ #include /* Common nested types */ -extern const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1]; +extern const struct nla_policy ovpn_epoch_nl_policy[OVPN_A_EPOCH_CIPHER_KEY_LEN + 1]; +extern const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_EPOCH + 1]; extern const struct nla_policy ovpn_keyconf_del_input_nl_policy[OVPN_A_KEYCONF_SLOT + 1]; extern const struct nla_policy ovpn_keyconf_get_nl_policy[OVPN_A_KEYCONF_CIPHER_ALG + 1]; extern const struct nla_policy ovpn_keyconf_swap_input_nl_policy[OVPN_A_KEYCONF_PEER_ID + 1]; diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c index 910e4e67a68a..14c91729b392 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -859,6 +859,40 @@ static int ovpn_nl_get_key_dir(struct genl_info *info, struct nlattr *key, return 0; } +static int ovpn_nl_get_epoch_key(struct genl_info *info, struct nlattr *key, + enum ovpn_cipher_alg cipher, + struct ovpn_epoch_prk *prk) +{ + struct nlattr *attrs[OVPN_A_EPOCH_MAX + 1]; + int ret; + + ret = nla_parse_nested(attrs, OVPN_A_EPOCH_MAX, key, + ovpn_epoch_nl_policy, info->extack); + if (ret) + return ret; + + switch (cipher) { + case OVPN_CIPHER_ALG_AES_GCM: + case OVPN_CIPHER_ALG_CHACHA20_POLY1305: + if (NL_REQ_ATTR_CHECK(info->extack, key, attrs, + OVPN_A_EPOCH_KEY) || + NL_REQ_ATTR_CHECK(info->extack, key, attrs, + OVPN_A_EPOCH_CIPHER_KEY_LEN)) + return -EINVAL; + + prk->key = nla_data(attrs[OVPN_A_EPOCH_KEY]); + prk->key_size = nla_len(attrs[OVPN_A_EPOCH_KEY]); + prk->cipher_key_len = + nla_get_u32(attrs[OVPN_A_EPOCH_CIPHER_KEY_LEN]); + break; + default: + NL_SET_ERR_MSG_MOD(info->extack, "unsupported cipher"); + return -EINVAL; + } + + return 0; +} + /** * ovpn_nl_key_new_doit - configure a new key for the specified peer * @skb: incoming netlink message @@ -887,9 +921,11 @@ static int ovpn_nl_get_key_dir(struct genl_info *info, struct nlattr *key, int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info) { struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1]; - struct ovpn_priv *ovpn = info->user_ptr[0]; struct ovpn_peer_key_reset pkr = {}; + struct ovpn_priv *ovpn = info->user_ptr[0]; struct ovpn_peer *peer; + bool direct_key; + bool epoch_key; u32 peer_id; int ret; @@ -911,28 +947,70 @@ int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info) NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, OVPN_A_KEYCONF_KEY_ID) || NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, - OVPN_A_KEYCONF_CIPHER_ALG) || - NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, - OVPN_A_KEYCONF_ENCRYPT_DIR) || - NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs, - OVPN_A_KEYCONF_DECRYPT_DIR)) + OVPN_A_KEYCONF_CIPHER_ALG)) return -EINVAL; pkr.slot = nla_get_u32(attrs[OVPN_A_KEYCONF_SLOT]); pkr.key.key_id = nla_get_u32(attrs[OVPN_A_KEYCONF_KEY_ID]); pkr.key.cipher_alg = nla_get_u32(attrs[OVPN_A_KEYCONF_CIPHER_ALG]); - ret = ovpn_nl_get_key_dir(info, attrs[OVPN_A_KEYCONF_ENCRYPT_DIR], - pkr.key.cipher_alg, - &pkr.key.direct.encrypt); - if (ret < 0) - return ret; + direct_key = attrs[OVPN_A_KEYCONF_ENCRYPT_DIR] || + attrs[OVPN_A_KEYCONF_DECRYPT_DIR]; + epoch_key = attrs[OVPN_A_KEYCONF_ENCRYPT_EPOCH] || + attrs[OVPN_A_KEYCONF_DECRYPT_EPOCH]; + if (direct_key == epoch_key) { + NL_SET_ERR_MSG_MOD(info->extack, + "specify exactly one key format"); + return -EINVAL; + } - ret = ovpn_nl_get_key_dir(info, attrs[OVPN_A_KEYCONF_DECRYPT_DIR], - pkr.key.cipher_alg, - &pkr.key.direct.decrypt); - if (ret < 0) - return ret; + if (direct_key) { + if (NL_REQ_ATTR_CHECK(info->extack, + info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_ENCRYPT_DIR) || + NL_REQ_ATTR_CHECK(info->extack, + info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_DECRYPT_DIR)) + return -EINVAL; + + pkr.key.use_epoch_keys = false; + ret = ovpn_nl_get_key_dir(info, + attrs[OVPN_A_KEYCONF_ENCRYPT_DIR], + pkr.key.cipher_alg, + &pkr.key.direct.encrypt); + if (ret < 0) + return ret; + + ret = ovpn_nl_get_key_dir(info, + attrs[OVPN_A_KEYCONF_DECRYPT_DIR], + pkr.key.cipher_alg, + &pkr.key.direct.decrypt); + if (ret < 0) + return ret; + } else { + if (NL_REQ_ATTR_CHECK(info->extack, + info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_ENCRYPT_EPOCH) || + NL_REQ_ATTR_CHECK(info->extack, + info->attrs[OVPN_A_KEYCONF], attrs, + OVPN_A_KEYCONF_DECRYPT_EPOCH)) + return -EINVAL; + + pkr.key.use_epoch_keys = true; + ret = ovpn_nl_get_epoch_key(info, + attrs[OVPN_A_KEYCONF_ENCRYPT_EPOCH], + pkr.key.cipher_alg, + &pkr.key.epoch.encrypt); + if (ret < 0) + return ret; + + ret = ovpn_nl_get_epoch_key(info, + attrs[OVPN_A_KEYCONF_DECRYPT_EPOCH], + pkr.key.cipher_alg, + &pkr.key.epoch.decrypt); + if (ret < 0) + return ret; + } peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]); peer = ovpn_peer_get_by_id(ovpn, peer_id); diff --git a/include/uapi/linux/ovpn.h b/include/uapi/linux/ovpn.h index 06690090a1a9..fa6436557abd 100644 --- a/include/uapi/linux/ovpn.h +++ b/include/uapi/linux/ovpn.h @@ -11,6 +11,7 @@ #define OVPN_FAMILY_VERSION 1 #define OVPN_NONCE_TAIL_SIZE 8 +#define OVPN_EPOCH_PRK_SIZE 32 enum ovpn_cipher_alg { OVPN_CIPHER_ALG_NONE, @@ -68,6 +69,8 @@ enum { OVPN_A_KEYCONF_CIPHER_ALG, OVPN_A_KEYCONF_ENCRYPT_DIR, OVPN_A_KEYCONF_DECRYPT_DIR, + OVPN_A_KEYCONF_ENCRYPT_EPOCH, + OVPN_A_KEYCONF_DECRYPT_EPOCH, __OVPN_A_KEYCONF_MAX, OVPN_A_KEYCONF_MAX = (__OVPN_A_KEYCONF_MAX - 1) @@ -81,6 +84,14 @@ enum { OVPN_A_KEYDIR_MAX = (__OVPN_A_KEYDIR_MAX - 1) }; +enum { + OVPN_A_EPOCH_KEY = 1, + OVPN_A_EPOCH_CIPHER_KEY_LEN, + + __OVPN_A_EPOCH_MAX, + OVPN_A_EPOCH_MAX = (__OVPN_A_EPOCH_MAX - 1) +}; + enum { OVPN_A_IFINDEX = 1, OVPN_A_PEER,