Merge tag 'net-next-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking changes from Jakub Kicinski:
 "WiFi 7 and sendpage changes are the biggest pieces of work for this
  release. The latter will definitely require fixes but I think that we
  got it to a reasonable point.

  Core:

   - Rework the sendpage & splice implementations

     Instead of feeding data into sockets page by page extend sendmsg
     handlers to support taking a reference on the data, controlled by a
     new flag called MSG_SPLICE_PAGES

     Rework the handling of unexpected-end-of-file to invoke an
     additional callback instead of trying to predict what the right
     combination of MORE/NOTLAST flags is

     Remove the MSG_SENDPAGE_NOTLAST flag completely

   - Implement SCM_PIDFD, a new type of CMSG type analogous to
     SCM_CREDENTIALS, but it contains pidfd instead of plain pid

   - Enable socket busy polling with CONFIG_RT

   - Improve reliability and efficiency of reporting for ref_tracker

   - Auto-generate a user space C library for various Netlink families

  Protocols:

   - Allow TCP to shrink the advertised window when necessary, prevent
     sk_rcvbuf auto-tuning from growing the window all the way up to
     tcp_rmem[2]

   - Use per-VMA locking for "page-flipping" TCP receive zerocopy

   - Prepare TCP for device-to-device data transfers, by making sure
     that payloads are always attached to skbs as page frags

   - Make the backoff time for the first N TCP SYN retransmissions
     linear. Exponential backoff is unnecessarily conservative

   - Create a new MPTCP getsockopt to retrieve all info
     (MPTCP_FULL_INFO)

   - Avoid waking up applications using TLS sockets until we have a full
     record

   - Allow using kernel memory for protocol ioctl callbacks, paving the
     way to issuing ioctls over io_uring

   - Add nolocalbypass option to VxLAN, forcing packets to be fully
     encapsulated even if they are destined for a local IP address

   - Make TCPv4 use consistent hash in TIME_WAIT and SYN_RECV. Ensure
     in-kernel ECMP implementation (e.g. Open vSwitch) select the same
     link for all packets. Support L4 symmetric hashing in Open vSwitch

   - PPPoE: make number of hash bits configurable

   - Allow DNS to be overwritten by DHCPACK in the in-kernel DHCP client
     (ipconfig)

   - Add layer 2 miss indication and filtering, allowing higher layers
     (e.g. ACL filters) to make forwarding decisions based on whether
     packet matched forwarding state in lower devices (bridge)

   - Support matching on Connectivity Fault Management (CFM) packets

   - Hide the "link becomes ready" IPv6 messages by demoting their
     printk level to debug

   - HSR: don't enable promiscuous mode if device offloads the proto

   - Support active scanning in IEEE 802.15.4

   - Continue work on Multi-Link Operation for WiFi 7

  BPF:

   - Add precision propagation for subprogs and callbacks. This allows
     maintaining verification efficiency when subprograms are used, or
     in fact passing the verifier at all for complex programs,
     especially those using open-coded iterators

   - Improve BPF's {g,s}setsockopt() length handling. Previously BPF
     assumed the length is always equal to the amount of written data.
     But some protos allow passing a NULL buffer to discover what the
     output buffer *should* be, without writing anything

   - Accept dynptr memory as memory arguments passed to helpers

   - Add routing table ID to bpf_fib_lookup BPF helper

   - Support O_PATH FDs in BPF_OBJ_PIN and BPF_OBJ_GET commands

   - Drop bpf_capable() check in BPF_MAP_FREEZE command (used to mark
     maps as read-only)

   - Show target_{obj,btf}_id in tracing link fdinfo

   - Addition of several new kfuncs (most of the names are
     self-explanatory):
      - Add a set of new dynptr kfuncs: bpf_dynptr_adjust(),
        bpf_dynptr_is_null(), bpf_dynptr_is_rdonly(), bpf_dynptr_size()
        and bpf_dynptr_clone().
      - bpf_task_under_cgroup()
      - bpf_sock_destroy() - force closing sockets
      - bpf_cpumask_first_and(), rework bpf_cpumask_any*() kfuncs

  Netfilter:

   - Relax set/map validation checks in nf_tables. Allow checking
     presence of an entry in a map without using the value

   - Increase ip_vs_conn_tab_bits range for 64BIT builds

   - Allow updating size of a set

   - Improve NAT tuple selection when connection is closing

  Driver API:

   - Integrate netdev with LED subsystem, to allow configuring HW
     "offloaded" blinking of LEDs based on link state and activity
     (i.e. packets coming in and out)

   - Support configuring rate selection pins of SFP modules

   - Factor Clause 73 auto-negotiation code out of the drivers, provide
     common helper routines

   - Add more fool-proof helpers for managing lifetime of MDIO devices
     associated with the PCS layer

   - Allow drivers to report advanced statistics related to Time Aware
     scheduler offload (taprio)

   - Allow opting out of VF statistics in link dump, to allow more VFs
     to fit into the message

   - Split devlink instance and devlink port operations

  New hardware / drivers:

   - Ethernet:
      - Synopsys EMAC4 IP support (stmmac)
      - Marvell 88E6361 8 port (5x1GE + 3x2.5GE) switches
      - Marvell 88E6250 7 port switches
      - Microchip LAN8650/1 Rev.B0 PHYs
      - MediaTek MT7981/MT7988 built-in 1GE PHY driver

   - WiFi:
      - Realtek RTL8192FU, 2.4 GHz, b/g/n mode, 2T2R, 300 Mbps
      - Realtek RTL8723DS (SDIO variant)
      - Realtek RTL8851BE

   - CAN:
      - Fintek F81604

  Drivers:

   - Ethernet NICs:
      - Intel (100G, ice):
         - support dynamic interrupt allocation
         - use meta data match instead of VF MAC addr on slow-path
      - nVidia/Mellanox:
         - extend link aggregation to handle 4, rather than just 2 ports
         - spawn sub-functions without any features by default
      - OcteonTX2:
         - support HTB (Tx scheduling/QoS) offload
         - make RSS hash generation configurable
         - support selecting Rx queue using TC filters
      - Wangxun (ngbe/txgbe):
         - add basic Tx/Rx packet offloads
         - add phylink support (SFP/PCS control)
      - Freescale/NXP (enetc):
         - report TAPRIO packet statistics
      - Solarflare/AMD:
         - support matching on IP ToS and UDP source port of outer
           header
         - VxLAN and GENEVE tunnel encapsulation over IPv4 or IPv6
         - add devlink dev info support for EF10

   - Virtual NICs:
      - Microsoft vNIC:
         - size the Rx indirection table based on requested
           configuration
         - support VLAN tagging
      - Amazon vNIC:
         - try to reuse Rx buffers if not fully consumed, useful for ARM
           servers running with 16kB pages
      - Google vNIC:
         - support TCP segmentation of >64kB frames

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - enable USXGMII (88E6191X)
      - Microchip:
         - lan966x: add support for Egress Stage 0 ACL engine
         - lan966x: support mapping packet priority to internal switch
           priority (based on PCP or DSCP)

   - Ethernet PHYs:
      - Broadcom PHYs:
         - support for Wake-on-LAN for BCM54210E/B50212E
         - report LPI counter
      - Microsemi PHYs: support RGMII delay configuration (VSC85xx)
      - Micrel PHYs: receive timestamp in the frame (LAN8841)
      - Realtek PHYs: support optional external PHY clock
      - Altera TSE PCS: merge the driver into Lynx PCS which it is a
        variant of

   - CAN: Kvaser PCIEcan:
      - support packet timestamping

   - WiFi:
      - Intel (iwlwifi):
         - major update for new firmware and Multi-Link Operation (MLO)
         - configuration rework to drop test devices and split the
           different families
         - support for segmented PNVM images and power tables
         - new vendor entries for PPAG (platform antenna gain) feature
      - Qualcomm 802.11ax (ath11k):
         - Multiple Basic Service Set Identifier (MBSSID) and Enhanced
           MBSSID Advertisement (EMA) support in AP mode
         - support factory test mode
      - RealTek (rtw89):
         - add RSSI based antenna diversity
         - support U-NII-4 channels on 5 GHz band
      - RealTek (rtl8xxxu):
         - AP mode support for 8188f
         - support USB RX aggregation for the newer chips"

* tag 'net-next-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1602 commits)
  net: scm: introduce and use scm_recv_unix helper
  af_unix: Skip SCM_PIDFD if scm->pid is NULL.
  net: lan743x: Simplify comparison
  netlink: Add __sock_i_ino() for __netlink_diag_dump().
  net: dsa: avoid suspicious RCU usage for synced VLAN-aware MAC addresses
  Revert "af_unix: Call scm_recv() only after scm_set_cred()."
  phylink: ReST-ify the phylink_pcs_neg_mode() kdoc
  libceph: Partially revert changes to support MSG_SPLICE_PAGES
  net: phy: mscc: fix packet loss due to RGMII delays
  net: mana: use vmalloc_array and vcalloc
  net: enetc: use vmalloc_array and vcalloc
  ionic: use vmalloc_array and vcalloc
  pds_core: use vmalloc_array and vcalloc
  gve: use vmalloc_array and vcalloc
  octeon_ep: use vmalloc_array and vcalloc
  net: usb: qmi_wwan: add u-blox 0x1312 composition
  perf trace: fix MSG_SPLICE_PAGES build error
  ipvlan: Fix return value of ipvlan_queue_xmit()
  netfilter: nf_tables: fix underflow in chain reference counter
  netfilter: nf_tables: unbind non-anonymous set if rule construction fails
  ...

1 files changed, 901 insertions, 0 deletions

diff --git a/tools/net/ynl/lib/ynl.c b/tools/net/ynl/lib/ynl.c
new file mode 100644
index 000000000000..514e0d69e731
--- /dev/null
+++ b/tools/net/ynl/lib/ynl.c
@@ -0,0 +1,901 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+#include <errno.h>
+#include <poll.h>
+#include <string.h>
+#include <stdlib.h>
+#include <linux/types.h>
+
+#include <libmnl/libmnl.h>
+#include <linux/genetlink.h>
+
+#include "ynl.h"
+
+#define ARRAY_SIZE(arr)		(sizeof(arr) / sizeof(*arr))
+
+#define __yerr_msg(yse, _msg...)					\
+	({								\
+		struct ynl_error *_yse = (yse);				\
+									\
+		if (_yse) {						\
+			snprintf(_yse->msg, sizeof(_yse->msg) - 1,  _msg); \
+			_yse->msg[sizeof(_yse->msg) - 1] = 0;		\
+		}							\
+	})
+
+#define __yerr_code(yse, _code...)		\
+	({					\
+		struct ynl_error *_yse = (yse);	\
+						\
+		if (_yse) {			\
+			_yse->code = _code;	\
+		}				\
+	})
+
+#define __yerr(yse, _code, _msg...)		\
+	({					\
+		__yerr_msg(yse, _msg);		\
+		__yerr_code(yse, _code);	\
+	})
+
+#define __perr(yse, _msg)		__yerr(yse, errno, _msg)
+
+#define yerr_msg(_ys, _msg...)		__yerr_msg(&(_ys)->err, _msg)
+#define yerr(_ys, _code, _msg...)	__yerr(&(_ys)->err, _code, _msg)
+#define perr(_ys, _msg)			__yerr(&(_ys)->err, errno, _msg)
+
+/* -- Netlink boiler plate */
+static int
+ynl_err_walk_report_one(struct ynl_policy_nest *policy, unsigned int type,
+			char *str, int str_sz, int *n)
+{
+	if (!policy) {
+		if (*n < str_sz)
+			*n += snprintf(str, str_sz, "!policy");
+		return 1;
+	}
+
+	if (type > policy->max_attr) {
+		if (*n < str_sz)
+			*n += snprintf(str, str_sz, "!oob");
+		return 1;
+	}
+
+	if (!policy->table[type].name) {
+		if (*n < str_sz)
+			*n += snprintf(str, str_sz, "!name");
+		return 1;
+	}
+
+	if (*n < str_sz)
+		*n += snprintf(str, str_sz - *n,
+			       ".%s", policy->table[type].name);
+	return 0;
+}
+
+static int
+ynl_err_walk(struct ynl_sock *ys, void *start, void *end, unsigned int off,
+	     struct ynl_policy_nest *policy, char *str, int str_sz,
+	     struct ynl_policy_nest **nest_pol)
+{
+	unsigned int astart_off, aend_off;
+	const struct nlattr *attr;
+	unsigned int data_len;
+	unsigned int type;
+	bool found = false;
+	int n = 0;
+
+	if (!policy) {
+		if (n < str_sz)
+			n += snprintf(str, str_sz, "!policy");
+		return n;
+	}
+
+	data_len = end - start;
+
+	mnl_attr_for_each_payload(start, data_len) {
+		astart_off = (char *)attr - (char *)start;
+		aend_off = astart_off + mnl_attr_get_payload_len(attr);
+		if (aend_off <= off)
+			continue;
+
+		found = true;
+		break;
+	}
+	if (!found)
+		return 0;
+
+	off -= astart_off;
+
+	type = mnl_attr_get_type(attr);
+
+	if (ynl_err_walk_report_one(policy, type, str, str_sz, &n))
+		return n;
+
+	if (!off) {
+		if (nest_pol)
+			*nest_pol = policy->table[type].nest;
+		return n;
+	}
+
+	if (!policy->table[type].nest) {
+		if (n < str_sz)
+			n += snprintf(str, str_sz, "!nest");
+		return n;
+	}
+
+	off -= sizeof(struct nlattr);
+	start =  mnl_attr_get_payload(attr);
+	end = start + mnl_attr_get_payload_len(attr);
+
+	return n + ynl_err_walk(ys, start, end, off, policy->table[type].nest,
+				&str[n], str_sz - n, nest_pol);
+}
+
+#define NLMSGERR_ATTR_MISS_TYPE (NLMSGERR_ATTR_POLICY + 1)
+#define NLMSGERR_ATTR_MISS_NEST (NLMSGERR_ATTR_POLICY + 2)
+#define NLMSGERR_ATTR_MAX (NLMSGERR_ATTR_MAX + 2)
+
+static int
+ynl_ext_ack_check(struct ynl_sock *ys, const struct nlmsghdr *nlh,
+		  unsigned int hlen)
+{
+	const struct nlattr *tb[NLMSGERR_ATTR_MAX + 1] = {};
+	char miss_attr[sizeof(ys->err.msg)];
+	char bad_attr[sizeof(ys->err.msg)];
+	const struct nlattr *attr;
+	const char *str = NULL;
+
+	if (!(nlh->nlmsg_flags & NLM_F_ACK_TLVS))
+		return MNL_CB_OK;
+
+	mnl_attr_for_each(attr, nlh, hlen) {
+		unsigned int len, type;
+
+		len = mnl_attr_get_payload_len(attr);
+		type = mnl_attr_get_type(attr);
+
+		if (type > NLMSGERR_ATTR_MAX)
+			continue;
+
+		tb[type] = attr;
+
+		switch (type) {
+		case NLMSGERR_ATTR_OFFS:
+		case NLMSGERR_ATTR_MISS_TYPE:
+		case NLMSGERR_ATTR_MISS_NEST:
+			if (len != sizeof(__u32))
+				return MNL_CB_ERROR;
+			break;
+		case NLMSGERR_ATTR_MSG:
+			str = mnl_attr_get_payload(attr);
+			if (str[len - 1])
+				return MNL_CB_ERROR;
+			break;
+		default:
+			break;
+		}
+	}
+
+	bad_attr[0] = '\0';
+	miss_attr[0] = '\0';
+
+	if (tb[NLMSGERR_ATTR_OFFS]) {
+		unsigned int n, off;
+		void *start, *end;
+
+		ys->err.attr_offs = mnl_attr_get_u32(tb[NLMSGERR_ATTR_OFFS]);
+
+		n = snprintf(bad_attr, sizeof(bad_attr), "%sbad attribute: ",
+			     str ? " (" : "");
+
+		start = mnl_nlmsg_get_payload_offset(ys->nlh,
+						     sizeof(struct genlmsghdr));
+		end = mnl_nlmsg_get_payload_tail(ys->nlh);
+
+		off = ys->err.attr_offs;
+		off -= sizeof(struct nlmsghdr);
+		off -= sizeof(struct genlmsghdr);
+
+		n += ynl_err_walk(ys, start, end, off, ys->req_policy,
+				  &bad_attr[n], sizeof(bad_attr) - n, NULL);
+
+		if (n >= sizeof(bad_attr))
+			n = sizeof(bad_attr) - 1;
+		bad_attr[n] = '\0';
+	}
+	if (tb[NLMSGERR_ATTR_MISS_TYPE]) {
+		struct ynl_policy_nest *nest_pol = NULL;
+		unsigned int n, off, type;
+		void *start, *end;
+		int n2;
+
+		type = mnl_attr_get_u32(tb[NLMSGERR_ATTR_MISS_TYPE]);
+
+		n = snprintf(miss_attr, sizeof(miss_attr), "%smissing attribute: ",
+			     bad_attr[0] ? ", " : (str ? " (" : ""));
+
+		start = mnl_nlmsg_get_payload_offset(ys->nlh,
+						     sizeof(struct genlmsghdr));
+		end = mnl_nlmsg_get_payload_tail(ys->nlh);
+
+		nest_pol = ys->req_policy;
+		if (tb[NLMSGERR_ATTR_MISS_NEST]) {
+			off = mnl_attr_get_u32(tb[NLMSGERR_ATTR_MISS_NEST]);
+			off -= sizeof(struct nlmsghdr);
+			off -= sizeof(struct genlmsghdr);
+
+			n += ynl_err_walk(ys, start, end, off, ys->req_policy,
+					  &miss_attr[n], sizeof(miss_attr) - n,
+					  &nest_pol);
+		}
+
+		n2 = 0;
+		ynl_err_walk_report_one(nest_pol, type, &miss_attr[n],
+					sizeof(miss_attr) - n, &n2);
+		n += n2;
+
+		if (n >= sizeof(miss_attr))
+			n = sizeof(miss_attr) - 1;
+		miss_attr[n] = '\0';
+	}
+
+	/* Implicitly depend on ys->err.code already set */
+	if (str)
+		yerr_msg(ys, "Kernel %s: '%s'%s%s%s",
+			 ys->err.code ? "error" : "warning",
+			 str, bad_attr, miss_attr,
+			 bad_attr[0] || miss_attr[0] ? ")" : "");
+	else if (bad_attr[0] || miss_attr[0])
+		yerr_msg(ys, "Kernel %s: %s%s",
+			 ys->err.code ? "error" : "warning",
+			 bad_attr, miss_attr);
+
+	return MNL_CB_OK;
+}
+
+static int ynl_cb_error(const struct nlmsghdr *nlh, void *data)
+{
+	const struct nlmsgerr *err = mnl_nlmsg_get_payload(nlh);
+	struct ynl_parse_arg *yarg = data;
+	unsigned int hlen;
+	int code;
+
+	code = err->error >= 0 ? err->error : -err->error;
+	yarg->ys->err.code = code;
+	errno = code;
+
+	hlen = sizeof(*err);
+	if (!(nlh->nlmsg_flags & NLM_F_CAPPED))
+		hlen += mnl_nlmsg_get_payload_len(&err->msg);
+
+	ynl_ext_ack_check(yarg->ys, nlh, hlen);
+
+	return code ? MNL_CB_ERROR : MNL_CB_STOP;
+}
+
+static int ynl_cb_done(const struct nlmsghdr *nlh, void *data)
+{
+	struct ynl_parse_arg *yarg = data;
+	int err;
+
+	err = *(int *)NLMSG_DATA(nlh);
+	if (err < 0) {
+		yarg->ys->err.code = -err;
+		errno = -err;
+
+		ynl_ext_ack_check(yarg->ys, nlh, sizeof(int));
+
+		return MNL_CB_ERROR;
+	}
+	return MNL_CB_STOP;
+}
+
+static int ynl_cb_noop(const struct nlmsghdr *nlh, void *data)
+{
+	return MNL_CB_OK;
+}
+
+mnl_cb_t ynl_cb_array[NLMSG_MIN_TYPE] = {
+	[NLMSG_NOOP]	= ynl_cb_noop,
+	[NLMSG_ERROR]	= ynl_cb_error,
+	[NLMSG_DONE]	= ynl_cb_done,
+	[NLMSG_OVERRUN]	= ynl_cb_noop,
+};
+
+/* Attribute validation */
+
+int ynl_attr_validate(struct ynl_parse_arg *yarg, const struct nlattr *attr)
+{
+	struct ynl_policy_attr *policy;
+	unsigned int type, len;
+	unsigned char *data;
+
+	data = mnl_attr_get_payload(attr);
+	len = mnl_attr_get_payload_len(attr);
+	type = mnl_attr_get_type(attr);
+	if (type > yarg->rsp_policy->max_attr) {
+		yerr(yarg->ys, YNL_ERROR_INTERNAL,
+		     "Internal error, validating unknown attribute");
+		return -1;
+	}
+
+	policy = &yarg->rsp_policy->table[type];
+
+	switch (policy->type) {
+	case YNL_PT_REJECT:
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Rejected attribute (%s)", policy->name);
+		return -1;
+	case YNL_PT_IGNORE:
+		break;
+	case YNL_PT_U8:
+		if (len == sizeof(__u8))
+			break;
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Invalid attribute (u8 %s)", policy->name);
+		return -1;
+	case YNL_PT_U16:
+		if (len == sizeof(__u16))
+			break;
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Invalid attribute (u16 %s)", policy->name);
+		return -1;
+	case YNL_PT_U32:
+		if (len == sizeof(__u32))
+			break;
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Invalid attribute (u32 %s)", policy->name);
+		return -1;
+	case YNL_PT_U64:
+		if (len == sizeof(__u64))
+			break;
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Invalid attribute (u64 %s)", policy->name);
+		return -1;
+	case YNL_PT_FLAG:
+		/* Let flags grow into real attrs, why not.. */
+		break;
+	case YNL_PT_NEST:
+		if (!len || len >= sizeof(*attr))
+			break;
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Invalid attribute (nest %s)", policy->name);
+		return -1;
+	case YNL_PT_BINARY:
+		if (!policy->len || len == policy->len)
+			break;
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Invalid attribute (binary %s)", policy->name);
+		return -1;
+	case YNL_PT_NUL_STR:
+		if ((!policy->len || len <= policy->len) && !data[len - 1])
+			break;
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Invalid attribute (string %s)", policy->name);
+		return -1;
+	default:
+		yerr(yarg->ys, YNL_ERROR_ATTR_INVALID,
+		     "Invalid attribute (unknown %s)", policy->name);
+		return -1;
+	}
+
+	return 0;
+}
+
+/* Generic code */
+
+static void ynl_err_reset(struct ynl_sock *ys)
+{
+	ys->err.code = 0;
+	ys->err.attr_offs = 0;
+	ys->err.msg[0] = 0;
+}
+
+struct nlmsghdr *ynl_msg_start(struct ynl_sock *ys, __u32 id, __u16 flags)
+{
+	struct nlmsghdr *nlh;
+
+	ynl_err_reset(ys);
+
+	nlh = ys->nlh = mnl_nlmsg_put_header(ys->tx_buf);
+	nlh->nlmsg_type	= id;
+	nlh->nlmsg_flags = flags;
+	nlh->nlmsg_seq = ++ys->seq;
+
+	return nlh;
+}
+
+struct nlmsghdr *
+ynl_gemsg_start(struct ynl_sock *ys, __u32 id, __u16 flags,
+		__u8 cmd, __u8 version)
+{
+	struct genlmsghdr gehdr;
+	struct nlmsghdr *nlh;
+	void *data;
+
+	nlh = ynl_msg_start(ys, id, flags);
+
+	memset(&gehdr, 0, sizeof(gehdr));
+	gehdr.cmd = cmd;
+	gehdr.version = version;
+
+	data = mnl_nlmsg_put_extra_header(nlh, sizeof(gehdr));
+	memcpy(data, &gehdr, sizeof(gehdr));
+
+	return nlh;
+}
+
+void ynl_msg_start_req(struct ynl_sock *ys, __u32 id)
+{
+	ynl_msg_start(ys, id, NLM_F_REQUEST | NLM_F_ACK);
+}
+
+void ynl_msg_start_dump(struct ynl_sock *ys, __u32 id)
+{
+	ynl_msg_start(ys, id, NLM_F_REQUEST | NLM_F_ACK | NLM_F_DUMP);
+}
+
+struct nlmsghdr *
+ynl_gemsg_start_req(struct ynl_sock *ys, __u32 id, __u8 cmd, __u8 version)
+{
+	return ynl_gemsg_start(ys, id, NLM_F_REQUEST | NLM_F_ACK, cmd, version);
+}
+
+struct nlmsghdr *
+ynl_gemsg_start_dump(struct ynl_sock *ys, __u32 id, __u8 cmd, __u8 version)
+{
+	return ynl_gemsg_start(ys, id, NLM_F_REQUEST | NLM_F_ACK | NLM_F_DUMP,
+			       cmd, version);
+}
+
+int ynl_recv_ack(struct ynl_sock *ys, int ret)
+{
+	if (!ret) {
+		yerr(ys, YNL_ERROR_EXPECT_ACK,
+		     "Expecting an ACK but nothing received");
+		return -1;
+	}
+
+	ret = mnl_socket_recvfrom(ys->sock, ys->rx_buf, MNL_SOCKET_BUFFER_SIZE);
+	if (ret < 0) {
+		perr(ys, "Socket receive failed");
+		return ret;
+	}
+	return mnl_cb_run(ys->rx_buf, ret, ys->seq, ys->portid,
+			  ynl_cb_null, ys);
+}
+
+int ynl_cb_null(const struct nlmsghdr *nlh, void *data)
+{
+	struct ynl_parse_arg *yarg = data;
+
+	yerr(yarg->ys, YNL_ERROR_UNEXPECT_MSG,
+	     "Received a message when none were expected");
+
+	return MNL_CB_ERROR;
+}
+
+/* Init/fini and genetlink boiler plate */
+static int
+ynl_get_family_info_mcast(struct ynl_sock *ys, const struct nlattr *mcasts)
+{
+	const struct nlattr *entry, *attr;
+	unsigned int i;
+
+	mnl_attr_for_each_nested(attr, mcasts)
+		ys->n_mcast_groups++;
+
+	if (!ys->n_mcast_groups)
+		return 0;
+
+	ys->mcast_groups = calloc(ys->n_mcast_groups,
+				  sizeof(*ys->mcast_groups));
+	if (!ys->mcast_groups)
+		return MNL_CB_ERROR;
+
+	i = 0;
+	mnl_attr_for_each_nested(entry, mcasts) {
+		mnl_attr_for_each_nested(attr, entry) {
+			if (mnl_attr_get_type(attr) == CTRL_ATTR_MCAST_GRP_ID)
+				ys->mcast_groups[i].id = mnl_attr_get_u32(attr);
+			if (mnl_attr_get_type(attr) == CTRL_ATTR_MCAST_GRP_NAME) {
+				strncpy(ys->mcast_groups[i].name,
+					mnl_attr_get_str(attr),
+					GENL_NAMSIZ - 1);
+				ys->mcast_groups[i].name[GENL_NAMSIZ - 1] = 0;
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int ynl_get_family_info_cb(const struct nlmsghdr *nlh, void *data)
+{
+	struct ynl_parse_arg *yarg = data;
+	struct ynl_sock *ys = yarg->ys;
+	const struct nlattr *attr;
+	bool found_id = true;
+
+	mnl_attr_for_each(attr, nlh, sizeof(struct genlmsghdr)) {
+		if (mnl_attr_get_type(attr) == CTRL_ATTR_MCAST_GROUPS)
+			if (ynl_get_family_info_mcast(ys, attr))
+				return MNL_CB_ERROR;
+
+		if (mnl_attr_get_type(attr) != CTRL_ATTR_FAMILY_ID)
+			continue;
+
+		if (mnl_attr_get_payload_len(attr) != sizeof(__u16)) {
+			yerr(ys, YNL_ERROR_ATTR_INVALID, "Invalid family ID");
+			return MNL_CB_ERROR;
+		}
+
+		ys->family_id = mnl_attr_get_u16(attr);
+		found_id = true;
+	}
+
+	if (!found_id) {
+		yerr(ys, YNL_ERROR_ATTR_MISSING, "Family ID missing");
+		return MNL_CB_ERROR;
+	}
+	return MNL_CB_OK;
+}
+
+static int ynl_sock_read_family(struct ynl_sock *ys, const char *family_name)
+{
+	struct ynl_parse_arg yarg = { .ys = ys, };
+	struct nlmsghdr *nlh;
+	int err;
+
+	nlh = ynl_gemsg_start_req(ys, GENL_ID_CTRL, CTRL_CMD_GETFAMILY, 1);
+	mnl_attr_put_strz(nlh, CTRL_ATTR_FAMILY_NAME, family_name);
+
+	err = mnl_socket_sendto(ys->sock, nlh, nlh->nlmsg_len);
+	if (err < 0) {
+		perr(ys, "failed to request socket family info");
+		return err;
+	}
+
+	err = mnl_socket_recvfrom(ys->sock, ys->rx_buf, MNL_SOCKET_BUFFER_SIZE);
+	if (err <= 0) {
+		perr(ys, "failed to receive the socket family info");
+		return err;
+	}
+	err = mnl_cb_run2(ys->rx_buf, err, ys->seq, ys->portid,
+			  ynl_get_family_info_cb, &yarg,
+			  ynl_cb_array, ARRAY_SIZE(ynl_cb_array));
+	if (err < 0) {
+		free(ys->mcast_groups);
+		perr(ys, "failed to receive the socket family info - no such family?");
+		return err;
+	}
+
+	return ynl_recv_ack(ys, err);
+}
+
+struct ynl_sock *
+ynl_sock_create(const struct ynl_family *yf, struct ynl_error *yse)
+{
+	struct ynl_sock *ys;
+	int one = 1;
+
+	ys = malloc(sizeof(*ys) + 2 * MNL_SOCKET_BUFFER_SIZE);
+	if (!ys)
+		return NULL;
+	memset(ys, 0, sizeof(*ys));
+
+	ys->family = yf;
+	ys->tx_buf = &ys->raw_buf[0];
+	ys->rx_buf = &ys->raw_buf[MNL_SOCKET_BUFFER_SIZE];
+	ys->ntf_last_next = &ys->ntf_first;
+
+	ys->sock = mnl_socket_open(NETLINK_GENERIC);
+	if (!ys->sock) {
+		__perr(yse, "failed to create a netlink socket");
+		goto err_free_sock;
+	}
+
+	if (mnl_socket_setsockopt(ys->sock, NETLINK_CAP_ACK,
+				  &one, sizeof(one))) {
+		__perr(yse, "failed to enable netlink ACK");
+		goto err_close_sock;
+	}
+	if (mnl_socket_setsockopt(ys->sock, NETLINK_EXT_ACK,
+				  &one, sizeof(one))) {
+		__perr(yse, "failed to enable netlink ext ACK");
+		goto err_close_sock;
+	}
+
+	ys->seq = random();
+	ys->portid = mnl_socket_get_portid(ys->sock);
+
+	if (ynl_sock_read_family(ys, yf->name)) {
+		if (yse)
+			memcpy(yse, &ys->err, sizeof(*yse));
+		goto err_close_sock;
+	}
+
+	return ys;
+
+err_close_sock:
+	mnl_socket_close(ys->sock);
+err_free_sock:
+	free(ys);
+	return NULL;
+}
+
+void ynl_sock_destroy(struct ynl_sock *ys)
+{
+	struct ynl_ntf_base_type *ntf;
+
+	mnl_socket_close(ys->sock);
+	while ((ntf = ynl_ntf_dequeue(ys)))
+		ynl_ntf_free(ntf);
+	free(ys->mcast_groups);
+	free(ys);
+}
+
+/* YNL multicast handling */
+
+void ynl_ntf_free(struct ynl_ntf_base_type *ntf)
+{
+	ntf->free(ntf);
+}
+
+int ynl_subscribe(struct ynl_sock *ys, const char *grp_name)
+{
+	unsigned int i;
+	int err;
+
+	for (i = 0; i < ys->n_mcast_groups; i++)
+		if (!strcmp(ys->mcast_groups[i].name, grp_name))
+			break;
+	if (i == ys->n_mcast_groups) {
+		yerr(ys, ENOENT, "Multicast group '%s' not found", grp_name);
+		return -1;
+	}
+
+	err = mnl_socket_setsockopt(ys->sock, NETLINK_ADD_MEMBERSHIP,
+				    &ys->mcast_groups[i].id,
+				    sizeof(ys->mcast_groups[i].id));
+	if (err < 0) {
+		perr(ys, "Subscribing to multicast group failed");
+		return -1;
+	}
+
+	return 0;
+}
+
+int ynl_socket_get_fd(struct ynl_sock *ys)
+{
+	return mnl_socket_get_fd(ys->sock);
+}
+
+struct ynl_ntf_base_type *ynl_ntf_dequeue(struct ynl_sock *ys)
+{
+	struct ynl_ntf_base_type *ntf;
+
+	if (!ynl_has_ntf(ys))
+		return NULL;
+
+	ntf = ys->ntf_first;
+	ys->ntf_first = ntf->next;
+	if (ys->ntf_last_next == &ntf->next)
+		ys->ntf_last_next = &ys->ntf_first;
+
+	return ntf;
+}
+
+static int ynl_ntf_parse(struct ynl_sock *ys, const struct nlmsghdr *nlh)
+{
+	struct ynl_parse_arg yarg = { .ys = ys, };
+	const struct ynl_ntf_info *info;
+	struct ynl_ntf_base_type *rsp;
+	struct genlmsghdr *gehdr;
+	int ret;
+
+	gehdr = mnl_nlmsg_get_payload(nlh);
+	if (gehdr->cmd >= ys->family->ntf_info_size)
+		return MNL_CB_ERROR;
+	info = &ys->family->ntf_info[gehdr->cmd];
+	if (!info->cb)
+		return MNL_CB_ERROR;
+
+	rsp = calloc(1, info->alloc_sz);
+	rsp->free = info->free;
+	yarg.data = rsp->data;
+	yarg.rsp_policy = info->policy;
+
+	ret = info->cb(nlh, &yarg);
+	if (ret <= MNL_CB_STOP)
+		goto err_free;
+
+	rsp->family = nlh->nlmsg_type;
+	rsp->cmd = gehdr->cmd;
+
+	*ys->ntf_last_next = rsp;
+	ys->ntf_last_next = &rsp->next;
+
+	return MNL_CB_OK;
+
+err_free:
+	info->free(rsp);
+	return MNL_CB_ERROR;
+}
+
+static int ynl_ntf_trampoline(const struct nlmsghdr *nlh, void *data)
+{
+	return ynl_ntf_parse((struct ynl_sock *)data, nlh);
+}
+
+int ynl_ntf_check(struct ynl_sock *ys)
+{
+	ssize_t len;
+	int err;
+
+	do {
+		/* libmnl doesn't let us pass flags to the recv to make
+		 * it non-blocking so we need to poll() or peek() :|
+		 */
+		struct pollfd pfd = { };
+
+		pfd.fd = mnl_socket_get_fd(ys->sock);
+		pfd.events = POLLIN;
+		err = poll(&pfd, 1, 1);
+		if (err < 1)
+			return err;
+
+		len = mnl_socket_recvfrom(ys->sock, ys->rx_buf,
+					  MNL_SOCKET_BUFFER_SIZE);
+		if (len < 0)
+			return len;
+
+		err = mnl_cb_run2(ys->rx_buf, len, ys->seq, ys->portid,
+				  ynl_ntf_trampoline, ys,
+				  ynl_cb_array, NLMSG_MIN_TYPE);
+		if (err < 0)
+			return err;
+	} while (err > 0);
+
+	return 0;
+}
+
+/* YNL specific helpers used by the auto-generated code */
+
+struct ynl_dump_list_type *YNL_LIST_END = (void *)(0xb4d123);
+
+void ynl_error_unknown_notification(struct ynl_sock *ys, __u8 cmd)
+{
+	yerr(ys, YNL_ERROR_UNKNOWN_NTF,
+	     "Unknown notification message type '%d'", cmd);
+}
+
+int ynl_error_parse(struct ynl_parse_arg *yarg, const char *msg)
+{
+	yerr(yarg->ys, YNL_ERROR_INV_RESP, "Error parsing response: %s", msg);
+	return MNL_CB_ERROR;
+}
+
+static int
+ynl_check_alien(struct ynl_sock *ys, const struct nlmsghdr *nlh, __u32 rsp_cmd)
+{
+	struct genlmsghdr *gehdr;
+
+	if (mnl_nlmsg_get_payload_len(nlh) < sizeof(*gehdr)) {
+		yerr(ys, YNL_ERROR_INV_RESP,
+		     "Kernel responded with truncated message");
+		return -1;
+	}
+
+	gehdr = mnl_nlmsg_get_payload(nlh);
+	if (gehdr->cmd != rsp_cmd)
+		return ynl_ntf_parse(ys, nlh);
+
+	return 0;
+}
+
+static int ynl_req_trampoline(const struct nlmsghdr *nlh, void *data)
+{
+	struct ynl_req_state *yrs = data;
+	int ret;
+
+	ret = ynl_check_alien(yrs->yarg.ys, nlh, yrs->rsp_cmd);
+	if (ret)
+		return ret < 0 ? MNL_CB_ERROR : MNL_CB_OK;
+
+	return yrs->cb(nlh, &yrs->yarg);
+}
+
+int ynl_exec(struct ynl_sock *ys, struct nlmsghdr *req_nlh,
+	     struct ynl_req_state *yrs)
+{
+	ssize_t len;
+	int err;
+
+	err = mnl_socket_sendto(ys->sock, req_nlh, req_nlh->nlmsg_len);
+	if (err < 0)
+		return err;
+
+	do {
+		len = mnl_socket_recvfrom(ys->sock, ys->rx_buf,
+					  MNL_SOCKET_BUFFER_SIZE);
+		if (len < 0)
+			return len;
+
+		err = mnl_cb_run2(ys->rx_buf, len, ys->seq, ys->portid,
+				  ynl_req_trampoline, yrs,
+				  ynl_cb_array, NLMSG_MIN_TYPE);
+		if (err < 0)
+			return err;
+	} while (err > 0);
+
+	return 0;
+}
+
+static int ynl_dump_trampoline(const struct nlmsghdr *nlh, void *data)
+{
+	struct ynl_dump_state *ds = data;
+	struct ynl_dump_list_type *obj;
+	struct ynl_parse_arg yarg = {};
+	int ret;
+
+	ret = ynl_check_alien(ds->ys, nlh, ds->rsp_cmd);
+	if (ret)
+		return ret < 0 ? MNL_CB_ERROR : MNL_CB_OK;
+
+	obj = calloc(1, ds->alloc_sz);
+	if (!obj)
+		return MNL_CB_ERROR;
+
+	if (!ds->first)
+		ds->first = obj;
+	if (ds->last)
+		ds->last->next = obj;
+	ds->last = obj;
+
+	yarg.ys = ds->ys;
+	yarg.rsp_policy = ds->rsp_policy;
+	yarg.data = &obj->data;
+
+	return ds->cb(nlh, &yarg);
+}
+
+static void *ynl_dump_end(struct ynl_dump_state *ds)
+{
+	if (!ds->first)
+		return YNL_LIST_END;
+
+	ds->last->next = YNL_LIST_END;
+	return ds->first;
+}
+
+int ynl_exec_dump(struct ynl_sock *ys, struct nlmsghdr *req_nlh,
+		  struct ynl_dump_state *yds)
+{
+	ssize_t len;
+	int err;
+
+	err = mnl_socket_sendto(ys->sock, req_nlh, req_nlh->nlmsg_len);
+	if (err < 0)
+		return err;
+
+	do {
+		len = mnl_socket_recvfrom(ys->sock, ys->rx_buf,
+					  MNL_SOCKET_BUFFER_SIZE);
+		if (len < 0)
+			goto err_close_list;
+
+		err = mnl_cb_run2(ys->rx_buf, len, ys->seq, ys->portid,
+				  ynl_dump_trampoline, yds,
+				  ynl_cb_array, NLMSG_MIN_TYPE);
+		if (err < 0)
+			goto err_close_list;
+	} while (err > 0);
+
+	yds->first = ynl_dump_end(yds);
+	return 0;
+
+err_close_list:
+	yds->first = ynl_dump_end(yds);
+	return -1;
+}