diff mbox series

[net-next,v3,20/24] ovpn: implement key add/del/swap via netlink

Message ID 20240506011637.27272-21-antonio@openvpn.net (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series Introducing OpenVPN Data Channel Offload | expand

Checks

Context Check Description
netdev/series_format fail Series longer than 15 patches
netdev/tree_selection success Clearly marked for net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; GEN HAS DIFF 2 files changed, 2613 insertions(+);
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 926 this patch: 926
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: openvpn-devel@lists.sourceforge.net
netdev/build_clang success Errors and warnings before: 937 this patch: 937
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 937 this patch: 937
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 209 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 2 this patch: 2
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-05-07--03-00 (tests: 1000)

Commit Message

Antonio Quartulli May 6, 2024, 1:16 a.m. UTC
This change introduces the netlink commands needed to add, delete and
swap keys for a specific peer.

Userspace is expected to use these commands to create, destroy and
rotate session keys for a specific peer.

Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
 drivers/net/ovpn/netlink.c | 193 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 190 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index 914b04631ae8..df14988c1f43 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -660,19 +660,206 @@  int ovpn_nl_del_peer_doit(struct sk_buff *skb, struct genl_info *info)
 	return ret;
 }
 
+static int ovpn_nl_get_key_dir(struct genl_info *info, struct nlattr *key,
+			       enum ovpn_cipher_alg cipher,
+			       struct ovpn_key_direction *dir)
+{
+	struct nlattr *attr, *attrs[OVPN_A_KEYDIR_MAX + 1];
+	int ret;
+
+	ret = nla_parse_nested(attrs, OVPN_A_KEYDIR_MAX, key,
+			       ovpn_keydir_nl_policy, info->extack);
+	if (ret)
+		return ret;
+
+	switch (cipher) {
+	case OVPN_CIPHER_ALG_AES_GCM:
+	case OVPN_CIPHER_ALG_CHACHA20_POLY1305:
+		attr = attrs[OVPN_A_KEYDIR_CIPHER_KEY];
+		if (!attr)
+			return -EINVAL;
+
+		dir->cipher_key = nla_data(attr);
+		dir->cipher_key_size = nla_len(attr);
+
+		attr = attrs[OVPN_A_KEYDIR_NONCE_TAIL];
+		/* These algorithms require a 96bit nonce,
+		 * Construct it by combining 4-bytes packet id and
+		 * 8-bytes nonce-tail from userspace
+		 */
+		if (!attr)
+			return -EINVAL;
+
+		dir->nonce_tail = nla_data(attr);
+		dir->nonce_tail_size = nla_len(attr);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 int ovpn_nl_set_key_doit(struct sk_buff *skb, struct genl_info *info)
 {
-	return -ENOTSUPP;
+	struct nlattr *p_attrs[OVPN_A_PEER_MAX + 1];
+	struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1];
+	struct ovpn_struct *ovpn = info->user_ptr[0];
+	struct ovpn_peer_key_reset pkr;
+	struct ovpn_peer *peer;
+	u32 peer_id;
+	int ret;
+
+	if (GENL_REQ_ATTR_CHECK(info, OVPN_A_PEER))
+		return -EINVAL;
+
+	ret = nla_parse_nested(p_attrs, OVPN_A_PEER_MAX,
+			       info->attrs[OVPN_A_PEER], ovpn_peer_nl_policy,
+			       info->extack);
+	if (ret)
+		return ret;
+
+	if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], p_attrs,
+			      OVPN_A_PEER_ID) ||
+	    NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], p_attrs,
+			      OVPN_A_PEER_KEYCONF))
+		return -EINVAL;
+
+	ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX,
+			       p_attrs[OVPN_A_PEER_KEYCONF],
+			       ovpn_keyconf_nl_policy, info->extack);
+	if (ret)
+		return ret;
+
+	if (NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+			      OVPN_A_KEYCONF_SLOT) ||
+	    NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+			      OVPN_A_KEYCONF_KEY_ID) ||
+	    NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+			      OVPN_A_KEYCONF_CIPHER_ALG) ||
+	    NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+			      OVPN_A_KEYCONF_ENCRYPT_DIR) ||
+	    NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+			      OVPN_A_KEYCONF_DECRYPT_DIR))
+		return -EINVAL;
+
+	peer_id = nla_get_u32(p_attrs[OVPN_A_PEER_ID]);
+	pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
+	pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]);
+	pkr.key.cipher_alg = nla_get_u16(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.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.decrypt);
+	if (ret < 0)
+		return ret;
+
+	peer = ovpn_peer_get_by_id(ovpn, peer_id);
+	if (!peer) {
+		netdev_dbg(ovpn->dev, "%s: no peer with id %u to set key for\n",
+			   __func__, peer_id);
+		return -ENOENT;
+	}
+
+	mutex_lock(&peer->crypto.mutex);
+	ret = ovpn_crypto_state_reset(&peer->crypto, &pkr);
+	if (ret < 0) {
+		netdev_dbg(ovpn->dev,
+			   "%s: cannot install new key for peer %u\n", __func__,
+			   peer_id);
+		goto unlock;
+	}
+
+	netdev_dbg(ovpn->dev, "%s: new key installed (id=%u) for peer %u\n",
+		   __func__, pkr.key.key_id, peer_id);
+unlock:
+	mutex_unlock(&peer->crypto.mutex);
+	ovpn_peer_put(peer);
+	return ret;
 }
 
 int ovpn_nl_swap_keys_doit(struct sk_buff *skb, struct genl_info *info)
 {
-	return -ENOTSUPP;
+	struct ovpn_struct *ovpn = info->user_ptr[0];
+	struct nlattr *attrs[OVPN_A_PEER + 1];
+	struct ovpn_peer *peer;
+	u32 peer_id;
+	int ret;
+
+	if (GENL_REQ_ATTR_CHECK(info, OVPN_A_PEER))
+		return -EINVAL;
+
+	ret = nla_parse_nested(attrs, OVPN_A_PEER_MAX, info->attrs[OVPN_A_PEER],
+			       ovpn_peer_nl_policy, info->extack);
+	if (ret)
+		return ret;
+
+	if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], attrs,
+			      OVPN_A_PEER_ID))
+		return -EINVAL;
+
+	peer_id = nla_get_u32(attrs[OVPN_A_PEER_ID]);
+
+	peer = ovpn_peer_get_by_id(ovpn, peer_id);
+	if (!peer)
+		return -ENOENT;
+
+	ovpn_crypto_key_slots_swap(&peer->crypto);
+	ovpn_peer_put(peer);
+
+	return 0;
 }
 
 int ovpn_nl_del_key_doit(struct sk_buff *skb, struct genl_info *info)
 {
-	return -ENOTSUPP;
+	struct nlattr *p_attrs[OVPN_A_PEER_MAX + 1];
+	struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1];
+	struct ovpn_struct *ovpn = info->user_ptr[0];
+	enum ovpn_key_slot slot;
+	struct ovpn_peer *peer;
+	u32 peer_id;
+	int ret;
+
+	if (GENL_REQ_ATTR_CHECK(info, OVPN_A_PEER))
+		return -EINVAL;
+
+	ret = nla_parse_nested(p_attrs, OVPN_A_PEER_MAX,
+			       info->attrs[OVPN_A_PEER], ovpn_peer_nl_policy,
+			       info->extack);
+	if (ret)
+		return ret;
+
+	if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], p_attrs,
+			      OVPN_A_PEER_ID) ||
+	    NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], p_attrs,
+			      OVPN_A_PEER_KEYCONF))
+		return -EINVAL;
+
+	ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX,
+			       p_attrs[OVPN_A_PEER_KEYCONF],
+			       ovpn_keyconf_nl_policy, info->extack);
+	if (ret)
+		return ret;
+
+	if (NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+			      OVPN_A_KEYCONF_SLOT))
+		return -EINVAL;
+
+	peer_id = nla_get_u32(p_attrs[OVPN_A_PEER_ID]);
+	slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
+
+	peer = ovpn_peer_get_by_id(ovpn, peer_id);
+	if (!peer)
+		return -ENOENT;
+
+	ovpn_crypto_key_slot_delete(&peer->crypto, slot);
+	ovpn_peer_put(peer);
+
+	return 0;
 }
 
 /**