From: Sven Eckelmann sven@narfation.org
The batman-adv configuration interface was implemented solely using sysfs. This approach was condemned by non-batadv developers as "huge mistake". Instead a netlink/genl based implementation was suggested.
Beside the mesh/soft-interface specific configuration, the VLANs on top of the mesh/soft-interface have configuration settings. The genl interface reflects this by allowing to get/set it using the vlan specific commands BATADV_CMD_GET_VLAN/BATADV_CMD_SET_VLAN.
The set command BATADV_CMD_SET_MESH will also notify interested userspace listeners of the "config" mcast group using the BATADV_CMD_SET_VLAN command message type that settings might have been changed and what the current values are.
Signed-off-by: Sven Eckelmann sven@narfation.org Signed-off-by: Simon Wunderlich sw@simonwunderlich.de --- include/uapi/linux/batman_adv.h | 17 ++++ net/batman-adv/netlink.c | 191 +++++++++++++++++++++++++++++++++++++++- 2 files changed, 206 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h index 62456a087ef6..10f3cc34fe16 100644 --- a/include/uapi/linux/batman_adv.h +++ b/include/uapi/linux/batman_adv.h @@ -345,6 +345,11 @@ enum batadv_nl_attrs { */ BATADV_ATTR_MCAST_FLAGS_PRIV,
+ /** + * @BATADV_ATTR_VLANID: VLAN id on top of soft interface + */ + BATADV_ATTR_VLANID, + /* add attributes above here, update the policy in netlink.c */
/** @@ -465,6 +470,18 @@ enum batadv_nl_commands { */ BATADV_CMD_SET_HARDIF,
+ /** + * @BATADV_CMD_GET_VLAN: Get attributes from a VLAN of the + * current softif + */ + BATADV_CMD_GET_VLAN, + + /** + * @BATADV_CMD_SET_VLAN: Set attributes for VLAN of the + * current softif + */ + BATADV_CMD_SET_VLAN, + /* add new commands above here */
/** diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c index a184e4225fb5..d40913bb9031 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -30,6 +30,7 @@ #include <linux/genetlink.h> #include <linux/gfp.h> #include <linux/if_ether.h> +#include <linux/if_vlan.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/list.h> @@ -84,6 +85,13 @@ enum batadv_genl_ops_flags { * saved in info->user_ptr[1] */ BATADV_FLAG_NEED_HARDIF = BIT(1), + + /** + * @BATADV_FLAG_NEED_VLAN: request requires valid vlan in + * attribute BATADV_ATTR_VLANID and expects a pointer to it to be + * saved in info->user_ptr[1] + */ + BATADV_FLAG_NEED_VLAN = BIT(2), };
static const struct genl_multicast_group batadv_netlink_mcgrps[] = { @@ -130,6 +138,7 @@ static const struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = { [BATADV_ATTR_DAT_CACHE_VID] = { .type = NLA_U16 }, [BATADV_ATTR_MCAST_FLAGS] = { .type = NLA_U32 }, [BATADV_ATTR_MCAST_FLAGS_PRIV] = { .type = NLA_U32 }, + [BATADV_ATTR_VLANID] = { .type = NLA_U16 }, };
/** @@ -654,6 +663,123 @@ batadv_netlink_dump_hardif(struct sk_buff *msg, struct netlink_callback *cb) }
/** + * batadv_netlink_vlan_fill() - Fill message with vlan attributes + * @msg: Netlink message to dump into + * @bat_priv: the bat priv with all the soft interface information + * @vlan: vlan which was modified + * @cmd: type of message to generate + * @portid: Port making netlink request + * @seq: sequence number for message + * @flags: Additional flags for message + * + * Return: 0 on success or negative error number in case of failure + */ +static int batadv_netlink_vlan_fill(struct sk_buff *msg, + struct batadv_priv *bat_priv, + struct batadv_softif_vlan *vlan, + enum batadv_nl_commands cmd, + u32 portid, u32 seq, int flags) +{ + void *hdr; + + hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, flags, cmd); + if (!hdr) + return -ENOBUFS; + + if (nla_put_u32(msg, BATADV_ATTR_MESH_IFINDEX, + bat_priv->soft_iface->ifindex)) + goto nla_put_failure; + + if (nla_put_u32(msg, BATADV_ATTR_VLANID, vlan->vid & VLAN_VID_MASK)) + goto nla_put_failure; + + genlmsg_end(msg, hdr); + return 0; + +nla_put_failure: + genlmsg_cancel(msg, hdr); + return -EMSGSIZE; +} + +/** + * batadv_netlink_notify_vlan() - send vlan attributes to listener + * @bat_priv: the bat priv with all the soft interface information + * @vlan: vlan which was modified + * + * Return: 0 on success, < 0 on error + */ +static int batadv_netlink_notify_vlan(struct batadv_priv *bat_priv, + struct batadv_softif_vlan *vlan) +{ + struct sk_buff *msg; + int ret; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + ret = batadv_netlink_vlan_fill(msg, bat_priv, vlan, + BATADV_CMD_SET_VLAN, 0, 0, 0); + if (ret < 0) { + nlmsg_free(msg); + return ret; + } + + genlmsg_multicast_netns(&batadv_netlink_family, + dev_net(bat_priv->soft_iface), msg, 0, + BATADV_NL_MCGRP_CONFIG, GFP_KERNEL); + + return 0; +} + +/** + * batadv_netlink_get_vlan() - Get vlan attributes + * @skb: Netlink message with request data + * @info: receiver information + * + * Return: 0 on success or negative error number in case of failure + */ +static int batadv_netlink_get_vlan(struct sk_buff *skb, struct genl_info *info) +{ + struct batadv_softif_vlan *vlan = info->user_ptr[1]; + struct batadv_priv *bat_priv = info->user_ptr[0]; + struct sk_buff *msg; + int ret; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + ret = batadv_netlink_vlan_fill(msg, bat_priv, vlan, BATADV_CMD_GET_VLAN, + info->snd_portid, info->snd_seq, 0); + if (ret < 0) { + nlmsg_free(msg); + return ret; + } + + ret = genlmsg_reply(msg, info); + + return ret; +} + +/** + * batadv_netlink_set_vlan() - Get vlan attributes + * @skb: Netlink message with request data + * @info: receiver information + * + * Return: 0 on success or negative error number in case of failure + */ +static int batadv_netlink_set_vlan(struct sk_buff *skb, struct genl_info *info) +{ + struct batadv_softif_vlan *vlan = info->user_ptr[1]; + struct batadv_priv *bat_priv = info->user_ptr[0]; + + batadv_netlink_notify_vlan(bat_priv, vlan); + + return 0; +} + +/** * batadv_get_softif_from_info() - Retrieve soft interface from genl attributes * @net: the applicable net namespace * @info: receiver information @@ -734,6 +860,34 @@ batadv_get_hardif_from_info(struct batadv_priv *bat_priv, struct net *net, }
/** + * batadv_get_vlan_from_info() - Retrieve vlan from genl attributes + * @bat_priv: the bat priv with all the soft interface information + * @net: the applicable net namespace + * @info: receiver information + * + * Return: Pointer to vlan on success (with increased refcnt), error pointer + * on error + */ +static struct batadv_softif_vlan * +batadv_get_vlan_from_info(struct batadv_priv *bat_priv, struct net *net, + struct genl_info *info) +{ + struct batadv_softif_vlan *vlan; + u16 vid; + + if (!info->attrs[BATADV_ATTR_VLANID]) + return ERR_PTR(-EINVAL); + + vid = nla_get_u16(info->attrs[BATADV_ATTR_VLANID]); + + vlan = batadv_softif_vlan_get(bat_priv, vid | BATADV_VLAN_HAS_TAG); + if (!vlan) + return ERR_PTR(-ENOENT); + + return vlan; +} + +/** * batadv_pre_doit() - Prepare batman-adv genl doit request * @ops: requested netlink operation * @skb: Netlink message with request data @@ -747,16 +901,17 @@ static int batadv_pre_doit(const struct genl_ops *ops, struct sk_buff *skb, struct net *net = genl_info_net(info); struct batadv_hard_iface *hard_iface; struct batadv_priv *bat_priv = NULL; + struct batadv_softif_vlan *vlan; struct net_device *soft_iface; u8 user_ptr1_flags; u8 mesh_dep_flags; int ret;
- user_ptr1_flags = BATADV_FLAG_NEED_HARDIF; + user_ptr1_flags = BATADV_FLAG_NEED_HARDIF | BATADV_FLAG_NEED_VLAN; if (WARN_ON(hweight8(ops->internal_flags & user_ptr1_flags) > 1)) return -EINVAL;
- mesh_dep_flags = BATADV_FLAG_NEED_HARDIF; + mesh_dep_flags = BATADV_FLAG_NEED_HARDIF | BATADV_FLAG_NEED_VLAN; if (WARN_ON((ops->internal_flags & mesh_dep_flags) && (~ops->internal_flags & BATADV_FLAG_NEED_MESH))) return -EINVAL; @@ -780,6 +935,16 @@ static int batadv_pre_doit(const struct genl_ops *ops, struct sk_buff *skb, info->user_ptr[1] = hard_iface; }
+ if (ops->internal_flags & BATADV_FLAG_NEED_VLAN) { + vlan = batadv_get_vlan_from_info(bat_priv, net, info); + if (IS_ERR(vlan)) { + ret = PTR_ERR(vlan); + goto err_put_softif; + } + + info->user_ptr[1] = vlan; + } + return 0;
err_put_softif: @@ -799,6 +964,7 @@ static void batadv_post_doit(const struct genl_ops *ops, struct sk_buff *skb, struct genl_info *info) { struct batadv_hard_iface *hard_iface; + struct batadv_softif_vlan *vlan; struct batadv_priv *bat_priv;
if (ops->internal_flags & BATADV_FLAG_NEED_HARDIF && @@ -808,6 +974,11 @@ static void batadv_post_doit(const struct genl_ops *ops, struct sk_buff *skb, batadv_hardif_put(hard_iface); }
+ if (ops->internal_flags & BATADV_FLAG_NEED_VLAN && info->user_ptr[1]) { + vlan = info->user_ptr[1]; + batadv_softif_vlan_put(vlan); + } + if (ops->internal_flags & BATADV_FLAG_NEED_MESH && info->user_ptr[0]) { bat_priv = info->user_ptr[0]; dev_put(bat_priv->soft_iface); @@ -920,6 +1091,22 @@ static const struct genl_ops batadv_netlink_ops[] = { .internal_flags = BATADV_FLAG_NEED_MESH | BATADV_FLAG_NEED_HARDIF, }, + { + .cmd = BATADV_CMD_GET_VLAN, + /* can be retrieved by unprivileged users */ + .policy = batadv_netlink_policy, + .doit = batadv_netlink_get_vlan, + .internal_flags = BATADV_FLAG_NEED_MESH | + BATADV_FLAG_NEED_VLAN, + }, + { + .cmd = BATADV_CMD_SET_VLAN, + .flags = GENL_ADMIN_PERM, + .policy = batadv_netlink_policy, + .doit = batadv_netlink_set_vlan, + .internal_flags = BATADV_FLAG_NEED_MESH | + BATADV_FLAG_NEED_VLAN, + }, };
struct genl_family batadv_netlink_family __ro_after_init = {