From: Johannes Berg Date: Wed, 19 Dec 2007 01:03:29 +0000 (+0100) Subject: cfg80211/nl80211: introduce key handling X-Git-Tag: v2.6.25-rc1~1162^2~941 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=41ade00f21a72d30911c6351a93823a491fffa39;p=linux-2.6 cfg80211/nl80211: introduce key handling This introduces key handling to cfg80211/nl80211. Default and group keys can be added, changed and removed; sequence counters for each key can be retrieved. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville Signed-off-by: David S. Miller --- diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h index 538ee1dd3d..8dc807d9c2 100644 --- a/include/linux/nl80211.h +++ b/include/linux/nl80211.h @@ -37,6 +37,16 @@ * userspace to request deletion of a virtual interface, then requires * attribute %NL80211_ATTR_IFINDEX. * + * @NL80211_CMD_GET_KEY: Get sequence counter information for a key specified + * by %NL80211_ATTR_KEY_IDX and/or %NL80211_ATTR_MAC. + * @NL80211_CMD_SET_KEY: Set key attributes %NL80211_ATTR_KEY_DEFAULT or + * %NL80211_ATTR_KEY_THRESHOLD. + * @NL80211_CMD_NEW_KEY: add a key with given %NL80211_ATTR_KEY_DATA, + * %NL80211_ATTR_KEY_IDX, %NL80211_ATTR_MAC and %NL80211_ATTR_KEY_CIPHER + * attributes. + * @NL80211_CMD_DEL_KEY: delete a key identified by %NL80211_ATTR_KEY_IDX + * or %NL80211_ATTR_MAC. + * * @NL80211_CMD_MAX: highest used command number * @__NL80211_CMD_AFTER_LAST: internal use */ @@ -54,6 +64,11 @@ enum nl80211_commands { NL80211_CMD_NEW_INTERFACE, NL80211_CMD_DEL_INTERFACE, + NL80211_CMD_GET_KEY, + NL80211_CMD_SET_KEY, + NL80211_CMD_NEW_KEY, + NL80211_CMD_DEL_KEY, + /* add commands here */ /* used to define NL80211_CMD_MAX below */ @@ -75,6 +90,17 @@ enum nl80211_commands { * @NL80211_ATTR_IFNAME: network interface name * @NL80211_ATTR_IFTYPE: type of virtual interface, see &enum nl80211_iftype * + * @NL80211_ATTR_MAC: MAC address (various uses) + * + * @NL80211_ATTR_KEY_DATA: (temporal) key data; for TKIP this consists of + * 16 bytes encryption key followed by 8 bytes each for TX and RX MIC + * keys + * @NL80211_ATTR_KEY_IDX: key ID (u8, 0-3) + * @NL80211_ATTR_KEY_CIPHER: key cipher suite (u32, as defined by IEEE 802.11 + * section 7.3.2.25.1, e.g. 0x000FAC04) + * @NL80211_ATTR_KEY_SEQ: transmit key sequence number (IV/PN) for TKIP and + * CCMP keys, each six bytes in little endian + * * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use */ @@ -89,6 +115,14 @@ enum nl80211_attrs { NL80211_ATTR_IFNAME, NL80211_ATTR_IFTYPE, + NL80211_ATTR_MAC, + + NL80211_ATTR_KEY_DATA, + NL80211_ATTR_KEY_IDX, + NL80211_ATTR_KEY_CIPHER, + NL80211_ATTR_KEY_SEQ, + NL80211_ATTR_KEY_DEFAULT, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index d30960e175..3db7dfa53b 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -49,6 +49,26 @@ extern int ieee80211_radiotap_iterator_next( struct ieee80211_radiotap_iterator *iterator); + /** + * struct key_params - key information + * + * Information about a key + * + * @key: key material + * @key_len: length of key material + * @cipher: cipher suite selector + * @seq: sequence counter (IV/PN) for TKIP and CCMP keys, only used + * with the get_key() callback, must be in little endian, + * length given by @seq_len. + */ +struct key_params { + u8 *key; + u8 *seq; + int key_len; + int seq_len; + u32 cipher; +}; + /* from net/wireless.h */ struct wiphy; @@ -71,6 +91,18 @@ struct wiphy; * * @change_virtual_intf: change type of virtual interface * + * @add_key: add a key with the given parameters. @mac_addr will be %NULL + * when adding a group key. + * + * @get_key: get information about the key with the given parameters. + * @mac_addr will be %NULL when requesting information for a group + * key. All pointers given to the @callback function need not be valid + * after it returns. + * + * @del_key: remove a key given the @mac_addr (%NULL for a group key) + * and @key_index + * + * @set_default_key: set the default key on an interface */ struct cfg80211_ops { int (*add_virtual_intf)(struct wiphy *wiphy, char *name, @@ -78,6 +110,18 @@ struct cfg80211_ops { int (*del_virtual_intf)(struct wiphy *wiphy, int ifindex); int (*change_virtual_intf)(struct wiphy *wiphy, int ifindex, enum nl80211_iftype type); + + int (*add_key)(struct wiphy *wiphy, struct net_device *netdev, + u8 key_index, u8 *mac_addr, + struct key_params *params); + int (*get_key)(struct wiphy *wiphy, struct net_device *netdev, + u8 key_index, u8 *mac_addr, void *cookie, + void (*callback)(void *cookie, struct key_params*)); + int (*del_key)(struct wiphy *wiphy, struct net_device *netdev, + u8 key_index, u8 *mac_addr); + int (*set_default_key)(struct wiphy *wiphy, + struct net_device *netdev, + u8 key_index); }; #endif /* __NET_CFG80211_H */ diff --git a/net/wireless/core.c b/net/wireless/core.c index febc33bc9c..cfc5fc5f9e 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -184,6 +184,9 @@ struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv) struct cfg80211_registered_device *drv; int alloc_size; + WARN_ON(!ops->add_key && ops->del_key); + WARN_ON(ops->add_key && !ops->del_key); + alloc_size = sizeof(*drv) + sizeof_priv; drv = kzalloc(alloc_size, GFP_KERNEL); diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 48b0d453e4..0909363885 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -61,6 +61,14 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = { [NL80211_ATTR_IFTYPE] = { .type = NLA_U32 }, [NL80211_ATTR_IFINDEX] = { .type = NLA_U32 }, [NL80211_ATTR_IFNAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ-1 }, + + [NL80211_ATTR_MAC] = { .type = NLA_BINARY, .len = ETH_ALEN }, + + [NL80211_ATTR_KEY_DATA] = { .type = NLA_BINARY, + .len = WLAN_MAX_KEY_LEN }, + [NL80211_ATTR_KEY_IDX] = { .type = NLA_U8 }, + [NL80211_ATTR_KEY_CIPHER] = { .type = NLA_U32 }, + [NL80211_ATTR_KEY_DEFAULT] = { .type = NLA_FLAG }, }; /* message building helper */ @@ -335,6 +343,263 @@ static int nl80211_del_interface(struct sk_buff *skb, struct genl_info *info) return err; } +struct get_key_cookie { + struct sk_buff *msg; + int error; +}; + +static void get_key_callback(void *c, struct key_params *params) +{ + struct get_key_cookie *cookie = c; + + if (params->key) + NLA_PUT(cookie->msg, NL80211_ATTR_KEY_DATA, + params->key_len, params->key); + + if (params->seq) + NLA_PUT(cookie->msg, NL80211_ATTR_KEY_SEQ, + params->seq_len, params->seq); + + if (params->cipher) + NLA_PUT_U32(cookie->msg, NL80211_ATTR_KEY_CIPHER, + params->cipher); + + return; + nla_put_failure: + cookie->error = 1; +} + +static int nl80211_get_key(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *drv; + int err; + struct net_device *dev; + u8 key_idx = 0; + u8 *mac_addr = NULL; + struct get_key_cookie cookie = { + .error = 0, + }; + void *hdr; + struct sk_buff *msg; + + if (info->attrs[NL80211_ATTR_KEY_IDX]) + key_idx = nla_get_u8(info->attrs[NL80211_ATTR_KEY_IDX]); + + if (key_idx > 3) + return -EINVAL; + + if (info->attrs[NL80211_ATTR_MAC]) + mac_addr = nla_data(info->attrs[NL80211_ATTR_MAC]); + + err = get_drv_dev_by_info_ifindex(info, &drv, &dev); + if (err) + return err; + + if (!drv->ops->get_key) { + err = -EOPNOTSUPP; + goto out; + } + + msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); + if (!msg) { + err = -ENOMEM; + goto out; + } + + hdr = nl80211hdr_put(msg, info->snd_pid, info->snd_seq, 0, + NL80211_CMD_NEW_KEY); + + if (IS_ERR(hdr)) { + err = PTR_ERR(hdr); + goto out; + } + + cookie.msg = msg; + + NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, dev->ifindex); + NLA_PUT_U8(msg, NL80211_ATTR_KEY_IDX, key_idx); + if (mac_addr) + NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr); + + rtnl_lock(); + err = drv->ops->get_key(&drv->wiphy, dev, key_idx, mac_addr, + &cookie, get_key_callback); + rtnl_unlock(); + + if (err) + goto out; + + if (cookie.error) + goto nla_put_failure; + + genlmsg_end(msg, hdr); + err = genlmsg_unicast(msg, info->snd_pid); + goto out; + + nla_put_failure: + err = -ENOBUFS; + nlmsg_free(msg); + out: + cfg80211_put_dev(drv); + dev_put(dev); + return err; +} + +static int nl80211_set_key(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *drv; + int err; + struct net_device *dev; + u8 key_idx; + + if (!info->attrs[NL80211_ATTR_KEY_IDX]) + return -EINVAL; + + key_idx = nla_get_u8(info->attrs[NL80211_ATTR_KEY_IDX]); + + if (key_idx > 3) + return -EINVAL; + + /* currently only support setting default key */ + if (!info->attrs[NL80211_ATTR_KEY_DEFAULT]) + return -EINVAL; + + err = get_drv_dev_by_info_ifindex(info, &drv, &dev); + if (err) + return err; + + if (!drv->ops->set_default_key) { + err = -EOPNOTSUPP; + goto out; + } + + rtnl_lock(); + err = drv->ops->set_default_key(&drv->wiphy, dev, key_idx); + rtnl_unlock(); + + out: + cfg80211_put_dev(drv); + dev_put(dev); + return err; +} + +static int nl80211_new_key(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *drv; + int err; + struct net_device *dev; + struct key_params params; + u8 key_idx = 0; + u8 *mac_addr = NULL; + + memset(¶ms, 0, sizeof(params)); + + if (!info->attrs[NL80211_ATTR_KEY_CIPHER]) + return -EINVAL; + + if (info->attrs[NL80211_ATTR_KEY_DATA]) { + params.key = nla_data(info->attrs[NL80211_ATTR_KEY_DATA]); + params.key_len = nla_len(info->attrs[NL80211_ATTR_KEY_DATA]); + } + + if (info->attrs[NL80211_ATTR_KEY_IDX]) + key_idx = nla_get_u8(info->attrs[NL80211_ATTR_KEY_IDX]); + + params.cipher = nla_get_u32(info->attrs[NL80211_ATTR_KEY_CIPHER]); + + if (info->attrs[NL80211_ATTR_MAC]) + mac_addr = nla_data(info->attrs[NL80211_ATTR_MAC]); + + if (key_idx > 3) + return -EINVAL; + + /* + * Disallow pairwise keys with non-zero index unless it's WEP + * (because current deployments use pairwise WEP keys with + * non-zero indizes but 802.11i clearly specifies to use zero) + */ + if (mac_addr && key_idx && + params.cipher != WLAN_CIPHER_SUITE_WEP40 && + params.cipher != WLAN_CIPHER_SUITE_WEP104) + return -EINVAL; + + /* TODO: add definitions for the lengths to linux/ieee80211.h */ + switch (params.cipher) { + case WLAN_CIPHER_SUITE_WEP40: + if (params.key_len != 5) + return -EINVAL; + break; + case WLAN_CIPHER_SUITE_TKIP: + if (params.key_len != 32) + return -EINVAL; + break; + case WLAN_CIPHER_SUITE_CCMP: + if (params.key_len != 16) + return -EINVAL; + break; + case WLAN_CIPHER_SUITE_WEP104: + if (params.key_len != 13) + return -EINVAL; + break; + default: + return -EINVAL; + } + + err = get_drv_dev_by_info_ifindex(info, &drv, &dev); + if (err) + return err; + + if (!drv->ops->add_key) { + err = -EOPNOTSUPP; + goto out; + } + + rtnl_lock(); + err = drv->ops->add_key(&drv->wiphy, dev, key_idx, mac_addr, ¶ms); + rtnl_unlock(); + + out: + cfg80211_put_dev(drv); + dev_put(dev); + return err; +} + +static int nl80211_del_key(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *drv; + int err; + struct net_device *dev; + u8 key_idx = 0; + u8 *mac_addr = NULL; + + if (info->attrs[NL80211_ATTR_KEY_IDX]) + key_idx = nla_get_u8(info->attrs[NL80211_ATTR_KEY_IDX]); + + if (key_idx > 3) + return -EINVAL; + + if (info->attrs[NL80211_ATTR_MAC]) + mac_addr = nla_data(info->attrs[NL80211_ATTR_MAC]); + + err = get_drv_dev_by_info_ifindex(info, &drv, &dev); + if (err) + return err; + + if (!drv->ops->del_key) { + err = -EOPNOTSUPP; + goto out; + } + + rtnl_lock(); + err = drv->ops->del_key(&drv->wiphy, dev, key_idx, mac_addr); + rtnl_unlock(); + + out: + cfg80211_put_dev(drv); + dev_put(dev); + return err; +} + static struct genl_ops nl80211_ops[] = { { .cmd = NL80211_CMD_GET_WIPHY, @@ -374,6 +639,30 @@ static struct genl_ops nl80211_ops[] = { .policy = nl80211_policy, .flags = GENL_ADMIN_PERM, }, + { + .cmd = NL80211_CMD_GET_KEY, + .doit = nl80211_get_key, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = NL80211_CMD_SET_KEY, + .doit = nl80211_set_key, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = NL80211_CMD_NEW_KEY, + .doit = nl80211_new_key, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = NL80211_CMD_DEL_KEY, + .doit = nl80211_del_key, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + }, }; /* multicast groups */