[CRYPTO_MSG_DELRNG - CRYPTO_MSG_BASE] = { .doit = crypto_del_rng },
};
-static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
{
struct nlattr *attrs[CRYPTOCFGA_MAX+1];
const struct crypto_link *link;
}
EXPORT_SYMBOL(ibnl_put_attr);
-static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
{
struct ibnl_client *client;
int type = nlh->nlmsg_type;
if (nlh->nlmsg_flags & NLM_F_REQUEST)
return;
- ibnl_rcv_msg(skb, nlh);
+ ibnl_rcv_msg(skb, nlh, NULL);
msglen = NLMSG_ALIGN(nlh->nlmsg_len);
if (msglen > skb->len)
next_msg:
if ((err) || (nlh->nlmsg_flags & NLM_F_ACK))
- netlink_ack(skb, nlh, err);
+ netlink_ack(skb, nlh, err, NULL);
skb_pull(skb, rlen);
}
return __netlink_kernel_create(net, unit, THIS_MODULE, cfg);
}
+/**
+ * struct netlink_ext_ack - netlink extended ACK report struct
+ * @_msg: message string to report - don't access directly, use
+ * %NL_SET_ERR_MSG
+ * @bad_attr: attribute with error
+ */
+struct netlink_ext_ack {
+ const char *_msg;
+ const struct nlattr *bad_attr;
+};
+
+/* Always use this macro, this allows later putting the
+ * message into a separate section or such for things
+ * like translation or listing all possible messages.
+ * Currently string formatting is not supported (due
+ * to the lack of an output buffer.)
+ */
+#define NL_SET_ERR_MSG(extack, msg) do { \
+ static const char _msg[] = (msg); \
+ \
+ (extack)->_msg = _msg; \
+} while (0)
+
extern void netlink_kernel_release(struct sock *sk);
extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
-extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
+extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err,
+ const struct netlink_ext_ack *extack);
extern int netlink_has_listeners(struct sock *sk, unsigned int group);
extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 portid, int nonblock);
};
int netlink_rcv_skb(struct sk_buff *skb,
- int (*cb)(struct sk_buff *, struct nlmsghdr *));
+ int (*cb)(struct sk_buff *, struct nlmsghdr *,
+ struct netlink_ext_ack *));
int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
unsigned int group, int report, gfp_t flags);
#define NLM_F_CREATE 0x400 /* Create, if it does not exist */
#define NLM_F_APPEND 0x800 /* Add to end of list */
+/* Flags for ACK message */
+#define NLM_F_CAPPED 0x100 /* request was capped */
+#define NLM_F_ACK_TLVS 0x200 /* extended ACK TVLs were included */
+
/*
4.4BSD ADD NLM_F_CREATE|NLM_F_EXCL
4.4BSD CHANGE NLM_F_REPLACE
struct nlmsgerr {
int error;
struct nlmsghdr msg;
+ /*
+ * followed by the message contents unless NETLINK_CAP_ACK was set
+ * or the ACK indicates success (error == 0)
+ * message length is aligned with NLMSG_ALIGN()
+ */
+ /*
+ * followed by TLVs defined in enum nlmsgerr_attrs
+ * if NETLINK_EXT_ACK was set
+ */
+};
+
+/**
+ * enum nlmsgerr_attrs - nlmsgerr attributes
+ * @NLMSGERR_ATTR_UNUSED: unused
+ * @NLMSGERR_ATTR_MSG: error message string (string)
+ * @NLMSGERR_ATTR_OFFS: offset of the invalid attribute in the original
+ * message, counting from the beginning of the header (u32)
+ * @__NLMSGERR_ATTR_MAX: number of attributes
+ * @NLMSGERR_ATTR_MAX: highest attribute number
+ */
+enum nlmsgerr_attrs {
+ NLMSGERR_ATTR_UNUSED,
+ NLMSGERR_ATTR_MSG,
+ NLMSGERR_ATTR_OFFS,
+
+ __NLMSGERR_ATTR_MAX,
+ NLMSGERR_ATTR_MAX = __NLMSGERR_ATTR_MAX - 1
};
#define NETLINK_ADD_MEMBERSHIP 1
#define NETLINK_LISTEN_ALL_NSID 8
#define NETLINK_LIST_MEMBERSHIPS 9
#define NETLINK_CAP_ACK 10
+#define NETLINK_EXT_ACK 11
struct nl_pktinfo {
__u32 group;
err = audit_receive_msg(skb, nlh);
/* if err or if this message says it wants a response */
if (err || (nlh->nlmsg_flags & NLM_F_ACK))
- netlink_ack(skb, nlh, err);
+ netlink_ack(skb, nlh, err, NULL);
nlh = nlmsg_next(nlh, &len);
}
/* Process one rtnetlink message. */
-static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
rtnl_doit_func doit;
return err;
}
-static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
{
int ret;
}
-#define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
+#define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err), NULL); return; } while (0)
static inline void dnrmg_receive_user_skb(struct sk_buff *skb)
{
return 0;
invalid:
- netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL);
+ netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL);
return 0;
nla_put_failure:
return 0;
invalid:
- netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL);
+ netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL);
return 0;
nla_put_failure:
* manually :-(
*/
if (nlh->nlmsg_flags & NLM_F_ACK)
- netlink_ack(cb->skb, nlh, ret);
+ netlink_ack(cb->skb, nlh, ret, NULL);
return ret;
}
}
EXPORT_SYMBOL_GPL(nfnetlink_unicast);
/* Process one complete nfnetlink message. */
-static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
const struct nfnl_callback *nc;
struct nfnl_err *nfnl_err, *next;
list_for_each_entry_safe(nfnl_err, next, err_list, head) {
- netlink_ack(skb, nfnl_err->nlh, nfnl_err->err);
+ netlink_ack(skb, nfnl_err->nlh, nfnl_err->err, NULL);
nfnl_err_del(nfnl_err);
}
}
int err;
if (subsys_id >= NFNL_SUBSYS_COUNT)
- return netlink_ack(skb, nlh, -EINVAL);
+ return netlink_ack(skb, nlh, -EINVAL, NULL);
replay:
status = 0;
skb = netlink_skb_clone(oskb, GFP_KERNEL);
if (!skb)
- return netlink_ack(oskb, nlh, -ENOMEM);
+ return netlink_ack(oskb, nlh, -ENOMEM, NULL);
nfnl_lock(subsys_id);
ss = nfnl_dereference_protected(subsys_id);
#endif
{
nfnl_unlock(subsys_id);
- netlink_ack(oskb, nlh, -EOPNOTSUPP);
+ netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL);
return kfree_skb(skb);
}
}
if (!ss->commit || !ss->abort) {
nfnl_unlock(subsys_id);
- netlink_ack(oskb, nlh, -EOPNOTSUPP);
+ netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL);
return kfree_skb(skb);
}
if (genid && ss->valid_genid && !ss->valid_genid(net, genid)) {
nfnl_unlock(subsys_id);
- netlink_ack(oskb, nlh, -ERESTART);
+ netlink_ack(oskb, nlh, -ERESTART, NULL);
return kfree_skb(skb);
}
* pointing to the batch header.
*/
nfnl_err_reset(&err_list);
- netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM);
+ netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM,
+ NULL);
status |= NFNL_BATCH_FAILURE;
goto done;
}
err = nla_parse(cda, NFNL_BATCH_MAX, attr, attrlen, nfnl_batch_policy);
if (err < 0) {
- netlink_ack(skb, nlh, err);
+ netlink_ack(skb, nlh, err, NULL);
return;
}
if (cda[NFNL_BATCH_GENID])
return;
if (!netlink_net_capable(skb, CAP_NET_ADMIN)) {
- netlink_ack(skb, nlh, -EPERM);
+ netlink_ack(skb, nlh, -EPERM, NULL);
return;
}
nlk->flags &= ~NETLINK_F_CAP_ACK;
err = 0;
break;
+ case NETLINK_EXT_ACK:
+ if (val)
+ nlk->flags |= NETLINK_F_EXT_ACK;
+ else
+ nlk->flags &= ~NETLINK_F_EXT_ACK;
+ err = 0;
+ break;
default:
err = -ENOPROTOOPT;
}
return -EFAULT;
err = 0;
break;
+ case NETLINK_EXT_ACK:
+ if (len < sizeof(int))
+ return -EINVAL;
+ len = sizeof(int);
+ val = nlk->flags & NETLINK_F_EXT_ACK ? 1 : 0;
+ if (put_user(len, optlen) || put_user(val, optval))
+ return -EFAULT;
+ err = 0;
+ break;
default:
err = -ENOPROTOOPT;
}
}
EXPORT_SYMBOL(__netlink_dump_start);
-void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
+void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err,
+ const struct netlink_ext_ack *extack)
{
struct sk_buff *skb;
struct nlmsghdr *rep;
struct nlmsgerr *errmsg;
size_t payload = sizeof(*errmsg);
+ size_t tlvlen = 0;
struct netlink_sock *nlk = nlk_sk(NETLINK_CB(in_skb).sk);
+ unsigned int flags = 0;
/* Error messages get the original request appened, unless the user
- * requests to cap the error message.
+ * requests to cap the error message, and get extra error data if
+ * requested.
*/
- if (!(nlk->flags & NETLINK_F_CAP_ACK) && err)
- payload += nlmsg_len(nlh);
+ if (err) {
+ if (!(nlk->flags & NETLINK_F_CAP_ACK))
+ payload += nlmsg_len(nlh);
+ else
+ flags |= NLM_F_CAPPED;
+ if (nlk->flags & NETLINK_F_EXT_ACK && extack) {
+ if (extack->_msg)
+ tlvlen += nla_total_size(strlen(extack->_msg) + 1);
+ if (extack->bad_attr)
+ tlvlen += nla_total_size(sizeof(u32));
+ }
+ } else {
+ flags |= NLM_F_CAPPED;
+ }
- skb = nlmsg_new(payload, GFP_KERNEL);
+ if (tlvlen)
+ flags |= NLM_F_ACK_TLVS;
+
+ skb = nlmsg_new(payload + tlvlen, GFP_KERNEL);
if (!skb) {
struct sock *sk;
}
rep = __nlmsg_put(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
- NLMSG_ERROR, payload, 0);
+ NLMSG_ERROR, payload, flags);
errmsg = nlmsg_data(rep);
errmsg->error = err;
memcpy(&errmsg->msg, nlh, payload > sizeof(*errmsg) ? nlh->nlmsg_len : sizeof(*nlh));
+
+ if (err && nlk->flags & NETLINK_F_EXT_ACK && extack) {
+ if (extack->_msg)
+ WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG,
+ extack->_msg));
+ if (extack->bad_attr &&
+ !WARN_ON((u8 *)extack->bad_attr < in_skb->data ||
+ (u8 *)extack->bad_attr >= in_skb->data +
+ in_skb->len))
+ WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS,
+ (u8 *)extack->bad_attr -
+ in_skb->data));
+ }
+
+ nlmsg_end(skb, rep);
+
netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid, MSG_DONTWAIT);
}
EXPORT_SYMBOL(netlink_ack);
int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
- struct nlmsghdr *))
+ struct nlmsghdr *,
+ struct netlink_ext_ack *))
{
+ struct netlink_ext_ack extack = {};
struct nlmsghdr *nlh;
int err;
if (nlh->nlmsg_type < NLMSG_MIN_TYPE)
goto ack;
- err = cb(skb, nlh);
+ err = cb(skb, nlh, &extack);
if (err == -EINTR)
goto skip;
ack:
if (nlh->nlmsg_flags & NLM_F_ACK || err)
- netlink_ack(skb, nlh, err);
+ netlink_ack(skb, nlh, err, &extack);
skip:
msglen = NLMSG_ALIGN(nlh->nlmsg_len);
#define NETLINK_F_RECV_NO_ENOBUFS 0x8
#define NETLINK_F_LISTEN_ALL_NSID 0x10
#define NETLINK_F_CAP_ACK 0x20
+#define NETLINK_F_EXT_ACK 0x40
#define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8)
#define NLGRPLONGS(x) (NLGRPSZ(x)/sizeof(unsigned long))
return err;
}
-static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
{
const struct genl_family *family;
int err;
[XFRM_MSG_GETSPDINFO - XFRM_MSG_BASE] = { .doit = xfrm_get_spdinfo },
};
-static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct nlattr *attrs[XFRMA_MAX+1];