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.
The main objects for this configuration is the mesh/soft-interface object. Its actual object in memory already contains most of the available configuration settings. The genl interface reflects this by allowing to get/set it using the mesh specific commands.
The BATADV_CMD_GET_MESH_INFO (or short version BATADV_CMD_GET_MESH) is reused as get command because it already provides the content of other information from the mesh/soft-interface which are not yet configuration specific.
The set command BATADV_CMD_SET_MESH will also notify interested userspace listeners of the "config" mcast group using the BATADV_CMD_SET_MESH command message type that settings might have been changed and what the current values are.
Signed-off-by: Sven Eckelmann sven@narfation.org --- include/uapi/linux/batman_adv.h | 16 +++- net/batman-adv/netlink.c | 160 +++++++++++++++++++------------- 2 files changed, 111 insertions(+), 65 deletions(-)
diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h index a28e76a7..b3394aac 100644 --- a/include/uapi/linux/batman_adv.h +++ b/include/uapi/linux/batman_adv.h @@ -27,6 +27,7 @@
#define BATADV_NL_NAME "batadv"
+#define BATADV_NL_MCAST_GROUP_CONFIG "config" #define BATADV_NL_MCAST_GROUP_TPMETER "tpmeter"
/** @@ -372,10 +373,14 @@ enum batadv_nl_commands { BATADV_CMD_UNSPEC,
/** - * @BATADV_CMD_GET_MESH_INFO: Query basic information about batman-adv - * device + * @BATADV_CMD_GET_MESH: Get attributes from softif/mesh */ - BATADV_CMD_GET_MESH_INFO, + BATADV_CMD_GET_MESH, + + /** + * @BATADV_CMD_GET_MESH_INFO: Alias for @BATADV_CMD_GET_MESH + */ + BATADV_CMD_GET_MESH_INFO = BATADV_CMD_GET_MESH,
/** * @BATADV_CMD_TP_METER: Start a tp meter session @@ -443,6 +448,11 @@ enum batadv_nl_commands { */ BATADV_CMD_GET_MCAST_FLAGS,
+ /** + * @BATADV_CMD_SET_MESH: Set attributes for softif/mesh + */ + BATADV_CMD_SET_MESH, + /* add new commands above here */
/** diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c index e56c40d1..179cc7cf 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -62,6 +62,7 @@ struct genl_family batadv_netlink_family;
/* multicast groups */ enum batadv_netlink_multicast_groups { + BATADV_NL_MCGRP_CONFIG, BATADV_NL_MCGRP_TPMETER, };
@@ -78,6 +79,7 @@ enum batadv_genl_ops_flags { };
static const struct genl_multicast_group batadv_netlink_mcgrps[] = { + [BATADV_NL_MCGRP_CONFIG] = { .name = BATADV_NL_MCAST_GROUP_CONFIG }, [BATADV_NL_MCGRP_TPMETER] = { .name = BATADV_NL_MCAST_GROUP_TPMETER }, };
@@ -138,20 +140,29 @@ batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype) }
/** - * batadv_netlink_mesh_info_put() - fill in generic information about mesh - * interface - * @msg: netlink message to be sent back - * @soft_iface: interface for which the data should be taken + * batadv_netlink_mesh_fill() - Fill message with mesh attributes + * @msg: Netlink message to dump into + * @bat_priv: the bat priv with all the soft interface information + * @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, < 0 on error + * Return: 0 on success or negative error number in case of failure */ -static int -batadv_netlink_mesh_info_put(struct sk_buff *msg, struct net_device *soft_iface) +static int batadv_netlink_mesh_fill(struct sk_buff *msg, + struct batadv_priv *bat_priv, + enum batadv_nl_commands cmd, + u32 portid, u32 seq, int flags) { - struct batadv_priv *bat_priv = netdev_priv(soft_iface); + struct net_device *soft_iface = bat_priv->soft_iface; struct batadv_hard_iface *primary_if = NULL; struct net_device *hard_iface; - int ret = -ENOBUFS; + void *hdr; + + hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family, flags, cmd); + if (!hdr) + return -ENOBUFS;
if (nla_put_string(msg, BATADV_ATTR_VERSION, BATADV_SOURCE_VERSION) || nla_put_string(msg, BATADV_ATTR_ALGO_NAME, @@ -162,16 +173,16 @@ batadv_netlink_mesh_info_put(struct sk_buff *msg, struct net_device *soft_iface) soft_iface->dev_addr) || nla_put_u8(msg, BATADV_ATTR_TT_TTVN, (u8)atomic_read(&bat_priv->tt.vn))) - goto out; + goto nla_put_failure;
#ifdef CONFIG_BATMAN_ADV_BLA if (nla_put_u16(msg, BATADV_ATTR_BLA_CRC, ntohs(bat_priv->bla.claim_dest.group))) - goto out; + goto nla_put_failure; #endif
if (batadv_mcast_mesh_info_put(msg, bat_priv)) - goto out; + goto nla_put_failure;
primary_if = batadv_primary_if_get_selected(bat_priv); if (primary_if && primary_if->if_status == BATADV_IF_ACTIVE) { @@ -183,77 +194,95 @@ batadv_netlink_mesh_info_put(struct sk_buff *msg, struct net_device *soft_iface) hard_iface->name) || nla_put(msg, BATADV_ATTR_HARD_ADDRESS, ETH_ALEN, hard_iface->dev_addr)) - goto out; + goto nla_put_failure; }
- ret = 0; + if (primary_if) + batadv_hardif_put(primary_if);
- out: + genlmsg_end(msg, hdr); + return 0; + +nla_put_failure: if (primary_if) batadv_hardif_put(primary_if);
- return ret; + genlmsg_cancel(msg, hdr); + return -EMSGSIZE; }
/** - * batadv_netlink_get_mesh_info() - handle incoming BATADV_CMD_GET_MESH_INFO - * netlink request - * @skb: received netlink message - * @info: receiver information + * batadv_netlink_notify_mesh() - send softif attributes to listener + * @bat_priv: the bat priv with all the soft interface information * * Return: 0 on success, < 0 on error */ -static int -batadv_netlink_get_mesh_info(struct sk_buff *skb, struct genl_info *info) +static int batadv_netlink_notify_mesh(struct batadv_priv *bat_priv) { - struct net *net = genl_info_net(info); - struct net_device *soft_iface; - struct sk_buff *msg = NULL; - void *msg_head; - int ifindex; + struct sk_buff *msg; int ret;
- if (!info->attrs[BATADV_ATTR_MESH_IFINDEX]) - return -EINVAL; - - ifindex = nla_get_u32(info->attrs[BATADV_ATTR_MESH_IFINDEX]); - if (!ifindex) - return -EINVAL; + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM;
- soft_iface = dev_get_by_index(net, ifindex); - if (!soft_iface || !batadv_softif_is_valid(soft_iface)) { - ret = -ENODEV; - goto out; + ret = batadv_netlink_mesh_fill(msg, bat_priv, BATADV_CMD_SET_MESH, + 0, 0, 0); + if (ret < 0) { + nlmsg_free(msg); + return ret; }
- msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); - if (!msg) { - ret = -ENOMEM; - goto out; - } + genlmsg_multicast_netns(&batadv_netlink_family, + dev_net(bat_priv->soft_iface), msg, 0, + BATADV_NL_MCGRP_CONFIG, GFP_KERNEL);
- msg_head = genlmsg_put(msg, info->snd_portid, info->snd_seq, - &batadv_netlink_family, 0, - BATADV_CMD_GET_MESH_INFO); - if (!msg_head) { - ret = -ENOBUFS; - goto out; - } + return 0; +}
- ret = batadv_netlink_mesh_info_put(msg, soft_iface); +/** + * batadv_netlink_get_mesh() - Get softif 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_mesh(struct sk_buff *skb, struct genl_info *info) +{ + struct batadv_priv *bat_priv = info->user_ptr[0]; + struct sk_buff *msg; + int ret;
- out: - if (soft_iface) - dev_put(soft_iface); + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM;
- if (ret) { - if (msg) - nlmsg_free(msg); + ret = batadv_netlink_mesh_fill(msg, bat_priv, BATADV_CMD_GET_MESH, + info->snd_portid, info->snd_seq, 0); + if (ret < 0) { + nlmsg_free(msg); return ret; }
- genlmsg_end(msg, msg_head); - return genlmsg_reply(msg, info); + ret = genlmsg_reply(msg, info); + + return ret; +} + +/** + * batadv_netlink_set_mesh() - Set softif 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_mesh(struct sk_buff *skb, struct genl_info *info) +{ + struct batadv_priv *bat_priv = info->user_ptr[0]; + + batadv_netlink_notify_mesh(bat_priv); + + return 0; }
/** @@ -600,10 +629,11 @@ static void batadv_post_doit(const struct genl_ops *ops, struct sk_buff *skb,
static const struct genl_ops batadv_netlink_ops[] = { { - .cmd = BATADV_CMD_GET_MESH_INFO, - .flags = GENL_ADMIN_PERM, + .cmd = BATADV_CMD_GET_MESH, + /* can be retrieved by unprivileged users */ .policy = batadv_netlink_policy, - .doit = batadv_netlink_get_mesh_info, + .doit = batadv_netlink_get_mesh, + .internal_flags = BATADV_FLAG_NEED_MESH, }, { .cmd = BATADV_CMD_TP_METER, @@ -685,7 +715,13 @@ static const struct genl_ops batadv_netlink_ops[] = { .policy = batadv_netlink_policy, .dumpit = batadv_mcast_flags_dump, }, - + { + .cmd = BATADV_CMD_SET_MESH, + .flags = GENL_ADMIN_PERM, + .policy = batadv_netlink_policy, + .doit = batadv_netlink_set_mesh, + .internal_flags = BATADV_FLAG_NEED_MESH, + }, };
struct genl_family batadv_netlink_family __ro_after_init = {