From 444be061d012f1a8ebf95292a648a4e0e2afa83f Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Sun, 11 Aug 2019 10:35:53 +0300 Subject: [PATCH] drop_monitor: Add a command to query current configuration Users should be able to query the current configuration of drop monitor before they start using it. Add a command to query the existing configuration which currently consists of alert mode and packet truncation length. Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller --- include/uapi/linux/net_dropmon.h | 2 ++ net/core/drop_monitor.c | 48 ++++++++++++++++++++++++++++++++ 2 files changed, 50 insertions(+) diff --git a/include/uapi/linux/net_dropmon.h b/include/uapi/linux/net_dropmon.h index 5cd7eb1f66ba..3b765a8428b5 100644 --- a/include/uapi/linux/net_dropmon.h +++ b/include/uapi/linux/net_dropmon.h @@ -54,6 +54,8 @@ enum { NET_DM_CMD_START, NET_DM_CMD_STOP, NET_DM_CMD_PACKET_ALERT, + NET_DM_CMD_CONFIG_GET, + NET_DM_CMD_CONFIG_NEW, _NET_DM_CMD_MAX, }; diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index 9f884adaa85f..135638474ab8 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -676,6 +676,50 @@ static int net_dm_cmd_trace(struct sk_buff *skb, return -EOPNOTSUPP; } +static int net_dm_config_fill(struct sk_buff *msg, struct genl_info *info) +{ + void *hdr; + + hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq, + &net_drop_monitor_family, 0, NET_DM_CMD_CONFIG_NEW); + if (!hdr) + return -EMSGSIZE; + + if (nla_put_u8(msg, NET_DM_ATTR_ALERT_MODE, net_dm_alert_mode)) + goto nla_put_failure; + + if (nla_put_u32(msg, NET_DM_ATTR_TRUNC_LEN, net_dm_trunc_len)) + goto nla_put_failure; + + genlmsg_end(msg, hdr); + + return 0; + +nla_put_failure: + genlmsg_cancel(msg, hdr); + return -EMSGSIZE; +} + +static int net_dm_cmd_config_get(struct sk_buff *skb, struct genl_info *info) +{ + struct sk_buff *msg; + int rc; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + rc = net_dm_config_fill(msg, info); + if (rc) + goto free_msg; + + return genlmsg_reply(msg, info); + +free_msg: + nlmsg_free(msg); + return rc; +} + static int dropmon_net_event(struct notifier_block *ev_block, unsigned long event, void *ptr) { @@ -738,6 +782,10 @@ static const struct genl_ops dropmon_ops[] = { .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, .doit = net_dm_cmd_trace, }, + { + .cmd = NET_DM_CMD_CONFIG_GET, + .doit = net_dm_cmd_config_get, + }, }; static int net_dm_nl_pre_doit(const struct genl_ops *ops,