From 7bdbe400d1b2aac116513f90b75969ad2365fba6 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Sat, 15 Aug 2015 22:39:49 +0300 Subject: [PATCH] nl80211: support vendor dumpit commands In order to transfer many items in vendor commands, support the dumpit netlink method for them. Signed-off-by: Johannes Berg --- include/net/cfg80211.h | 9 ++ net/wireless/nl80211.c | 192 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 201 insertions(+) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index f0889a247643..0f54c9ef4c7d 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -2971,12 +2971,21 @@ enum wiphy_vendor_command_flags { * @doit: callback for the operation, note that wdev is %NULL if the * flags didn't ask for a wdev and non-%NULL otherwise; the data * pointer may be %NULL if userspace provided no data at all + * @dumpit: dump callback, for transferring bigger/multiple items. The + * @storage points to cb->args[5], ie. is preserved over the multiple + * dumpit calls. + * It's recommended to not have the same sub command with both @doit and + * @dumpit, so that userspace can assume certain ones are get and others + * are used with dump requests. */ struct wiphy_vendor_command { struct nl80211_vendor_cmd_info info; u32 flags; int (*doit)(struct wiphy *wiphy, struct wireless_dev *wdev, const void *data, int data_len); + int (*dumpit)(struct wiphy *wiphy, struct wireless_dev *wdev, + struct sk_buff *skb, const void *data, int data_len, + unsigned long *storage); }; /** diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 5d8748b4c8a2..a4e6c951950f 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -3,6 +3,7 @@ * * Copyright 2006-2010 Johannes Berg * Copyright 2013-2014 Intel Mobile Communications GmbH + * Copyright 2015 Intel Deutschland GmbH */ #include @@ -9938,6 +9939,9 @@ static int nl80211_vendor_cmd(struct sk_buff *skb, struct genl_info *info) if (!wdev->netdev && !wdev->p2p_started) return -ENETDOWN; } + + if (!vcmd->doit) + return -EOPNOTSUPP; } else { wdev = NULL; } @@ -9957,6 +9961,193 @@ static int nl80211_vendor_cmd(struct sk_buff *skb, struct genl_info *info) return -EOPNOTSUPP; } +static int nl80211_prepare_vendor_dump(struct sk_buff *skb, + struct netlink_callback *cb, + struct cfg80211_registered_device **rdev, + struct wireless_dev **wdev) +{ + u32 vid, subcmd; + unsigned int i; + int vcmd_idx = -1; + int err; + void *data = NULL; + unsigned int data_len = 0; + + rtnl_lock(); + + if (cb->args[0]) { + /* subtract the 1 again here */ + struct wiphy *wiphy = wiphy_idx_to_wiphy(cb->args[0] - 1); + struct wireless_dev *tmp; + + if (!wiphy) { + err = -ENODEV; + goto out_unlock; + } + *rdev = wiphy_to_rdev(wiphy); + *wdev = NULL; + + if (cb->args[1]) { + list_for_each_entry(tmp, &(*rdev)->wdev_list, list) { + if (tmp->identifier == cb->args[1] - 1) { + *wdev = tmp; + break; + } + } + } + + /* keep rtnl locked in successful case */ + return 0; + } + + err = nlmsg_parse(cb->nlh, GENL_HDRLEN + nl80211_fam.hdrsize, + nl80211_fam.attrbuf, nl80211_fam.maxattr, + nl80211_policy); + if (err) + goto out_unlock; + + if (!nl80211_fam.attrbuf[NL80211_ATTR_VENDOR_ID] || + !nl80211_fam.attrbuf[NL80211_ATTR_VENDOR_SUBCMD]) { + err = -EINVAL; + goto out_unlock; + } + + *wdev = __cfg80211_wdev_from_attrs(sock_net(skb->sk), + nl80211_fam.attrbuf); + if (IS_ERR(*wdev)) + *wdev = NULL; + + *rdev = __cfg80211_rdev_from_attrs(sock_net(skb->sk), + nl80211_fam.attrbuf); + if (IS_ERR(*rdev)) { + err = PTR_ERR(*rdev); + goto out_unlock; + } + + vid = nla_get_u32(nl80211_fam.attrbuf[NL80211_ATTR_VENDOR_ID]); + subcmd = nla_get_u32(nl80211_fam.attrbuf[NL80211_ATTR_VENDOR_SUBCMD]); + + for (i = 0; i < (*rdev)->wiphy.n_vendor_commands; i++) { + const struct wiphy_vendor_command *vcmd; + + vcmd = &(*rdev)->wiphy.vendor_commands[i]; + + if (vcmd->info.vendor_id != vid || vcmd->info.subcmd != subcmd) + continue; + + if (!vcmd->dumpit) { + err = -EOPNOTSUPP; + goto out_unlock; + } + + vcmd_idx = i; + break; + } + + if (vcmd_idx < 0) { + err = -EOPNOTSUPP; + goto out_unlock; + } + + if (nl80211_fam.attrbuf[NL80211_ATTR_VENDOR_DATA]) { + data = nla_data(nl80211_fam.attrbuf[NL80211_ATTR_VENDOR_DATA]); + data_len = nla_len(nl80211_fam.attrbuf[NL80211_ATTR_VENDOR_DATA]); + } + + /* 0 is the first index - add 1 to parse only once */ + cb->args[0] = (*rdev)->wiphy_idx + 1; + /* add 1 to know if it was NULL */ + cb->args[1] = *wdev ? (*wdev)->identifier + 1 : 0; + cb->args[2] = vcmd_idx; + cb->args[3] = (unsigned long)data; + cb->args[4] = data_len; + + /* keep rtnl locked in successful case */ + return 0; + out_unlock: + rtnl_unlock(); + return err; +} + +static int nl80211_vendor_cmd_dump(struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct cfg80211_registered_device *rdev; + struct wireless_dev *wdev; + unsigned int vcmd_idx; + const struct wiphy_vendor_command *vcmd; + void *data; + int data_len; + int err; + struct nlattr *vendor_data; + + err = nl80211_prepare_vendor_dump(skb, cb, &rdev, &wdev); + if (err) + return err; + + vcmd_idx = cb->args[2]; + data = (void *)cb->args[3]; + data_len = cb->args[4]; + vcmd = &rdev->wiphy.vendor_commands[vcmd_idx]; + + if (vcmd->flags & (WIPHY_VENDOR_CMD_NEED_WDEV | + WIPHY_VENDOR_CMD_NEED_NETDEV)) { + if (!wdev) + return -EINVAL; + if (vcmd->flags & WIPHY_VENDOR_CMD_NEED_NETDEV && + !wdev->netdev) + return -EINVAL; + + if (vcmd->flags & WIPHY_VENDOR_CMD_NEED_RUNNING) { + if (wdev->netdev && + !netif_running(wdev->netdev)) + return -ENETDOWN; + if (!wdev->netdev && !wdev->p2p_started) + return -ENETDOWN; + } + } + + while (1) { + void *hdr = nl80211hdr_put(skb, NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + NL80211_CMD_VENDOR); + if (!hdr) + break; + + if (nla_put_u32(skb, NL80211_ATTR_WIPHY, rdev->wiphy_idx) || + (wdev && nla_put_u64(skb, NL80211_ATTR_WDEV, + wdev_id(wdev)))) { + genlmsg_cancel(skb, hdr); + break; + } + + vendor_data = nla_nest_start(skb, NL80211_ATTR_VENDOR_DATA); + if (!vendor_data) { + genlmsg_cancel(skb, hdr); + break; + } + + err = vcmd->dumpit(&rdev->wiphy, wdev, skb, data, data_len, + (unsigned long *)&cb->args[5]); + nla_nest_end(skb, vendor_data); + + if (err == -ENOBUFS || err == -ENOENT) { + genlmsg_cancel(skb, hdr); + break; + } else if (err) { + genlmsg_cancel(skb, hdr); + goto out; + } + + genlmsg_end(skb, hdr); + } + + err = skb->len; + out: + rtnl_unlock(); + return err; +} + struct sk_buff *__cfg80211_alloc_reply_skb(struct wiphy *wiphy, enum nl80211_commands cmd, enum nl80211_attrs attr, @@ -10994,6 +11185,7 @@ static const struct genl_ops nl80211_ops[] = { { .cmd = NL80211_CMD_VENDOR, .doit = nl80211_vendor_cmd, + .dumpit = nl80211_vendor_cmd_dump, .policy = nl80211_policy, .flags = GENL_ADMIN_PERM, .internal_flags = NL80211_FLAG_NEED_WIPHY | -- 2.39.5