nl80211: support the MAC80211_HWSIM netlink protocol family

The mac80211_hwsim module exposes a custom generic netlink family for
managing simulated phys and userspace data frame transmission.

Since hwsim functionality is closely related to nl80211 and useful to
e.g. manage simulated wireless testbeds, I decided to include support
directly into the nl80211 module.

Example calls for creating and destroying hwsim wiphys:

    nl80211.request(nl80211.const.HWSIM_CMD_NEW_RADIO, 0, {
        perm_addr: "02:11:22:33:44:55",
        support_p2p_device: true
    });

    nl80211.request(nl80211.const.HWSIM_CMD_DEL_RADIO, 0, {
        radio_name: "phy2"
    });

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

2 files changed, 211 insertions, 16 deletions

diff --git a/include/linux/mac80211_hwsim.h b/include/linux/mac80211_hwsim.h
new file mode 100644
index 0000000..0f21885
--- /dev/null
+++ b/include/linux/mac80211_hwsim.h
@@ -0,0 +1,83 @@
+/* Upstream source:
+ * https://github.com/torvalds/linux/blob/master/drivers/net/wireless/virtual/mac80211_hwsim.h
+ */
+
+#ifndef __LINUX_MAC80211_HWSIM_H
+#define __LINUX_MAC80211_HWSIM_H
+
+#include <stdint.h>
+#include <linux/nl80211.h>
+
+enum hwsim_commands {
+	HWSIM_CMD_OFFSET = NL80211_CMD_MAX,
+	HWSIM_CMD_REGISTER,
+	HWSIM_CMD_FRAME,
+	HWSIM_CMD_TX_INFO_FRAME,
+	HWSIM_CMD_NEW_RADIO,
+	HWSIM_CMD_DEL_RADIO,
+	HWSIM_CMD_GET_RADIO,
+	HWSIM_CMD_ADD_MAC_ADDR,
+	HWSIM_CMD_DEL_MAC_ADDR,
+	HWSIM_CMD_START_PMSR,
+	HWSIM_CMD_ABORT_PMSR,
+	HWSIM_CMD_REPORT_PMSR,
+};
+
+enum hwsim_attrs {
+	HWSIM_ATTR_UNSPEC,
+	HWSIM_ATTR_ADDR_RECEIVER,
+	HWSIM_ATTR_ADDR_TRANSMITTER,
+	HWSIM_ATTR_FRAME,
+	HWSIM_ATTR_FLAGS,
+	HWSIM_ATTR_RX_RATE,
+	HWSIM_ATTR_SIGNAL,
+	HWSIM_ATTR_TX_INFO,
+	HWSIM_ATTR_COOKIE,
+	HWSIM_ATTR_CHANNELS,
+	HWSIM_ATTR_RADIO_ID,
+	HWSIM_ATTR_REG_HINT_ALPHA2,
+	HWSIM_ATTR_REG_CUSTOM_REG,
+	HWSIM_ATTR_REG_STRICT_REG,
+	HWSIM_ATTR_SUPPORT_P2P_DEVICE,
+	HWSIM_ATTR_USE_CHANCTX,
+	HWSIM_ATTR_DESTROY_RADIO_ON_CLOSE,
+	HWSIM_ATTR_RADIO_NAME,
+	HWSIM_ATTR_NO_VIF,
+	HWSIM_ATTR_FREQ,
+	HWSIM_ATTR_PAD,
+	HWSIM_ATTR_TX_INFO_FLAGS,
+	HWSIM_ATTR_PERM_ADDR,
+	HWSIM_ATTR_IFTYPE_SUPPORT,
+	HWSIM_ATTR_CIPHER_SUPPORT,
+	HWSIM_ATTR_MLO_SUPPORT,
+	HWSIM_ATTR_PMSR_SUPPORT,
+	HWSIM_ATTR_PMSR_REQUEST,
+	HWSIM_ATTR_PMSR_RESULT,
+};
+
+enum hwsim_rate_info_attributes {
+	HWSIM_RATE_INFO_ATTR_UNSPEC,
+	HWSIM_RATE_INFO_ATTR_FLAGS,
+	HWSIM_RATE_INFO_ATTR_MCS,
+	HWSIM_RATE_INFO_ATTR_LEGACY,
+	HWSIM_RATE_INFO_ATTR_NSS,
+	HWSIM_RATE_INFO_ATTR_BW,
+	HWSIM_RATE_INFO_ATTR_HE_GI,
+	HWSIM_RATE_INFO_ATTR_HE_DCM,
+	HWSIM_RATE_INFO_ATTR_HE_RU_ALLOC,
+	HWSIM_RATE_INFO_ATTR_N_BOUNDED_CH,
+	HWSIM_RATE_INFO_ATTR_EHT_GI,
+	HWSIM_RATE_INFO_ATTR_EHT_RU_ALLOC,
+};
+
+struct hwsim_tx_rate {
+	int8_t idx;
+	uint8_t count;
+} __attribute__((packed));
+
+struct hwsim_tx_rate_flag {
+	int8_t idx;
+	uint16_t flags;
+} __attribute__((packed));
+
+#endif /* __LINUX_MAC80211_HWSIM_H */
diff --git a/lib/nl80211.c b/lib/nl80211.c
index ce0db7c..feebaeb 100644
--- a/lib/nl80211.c
+++ b/lib/nl80211.c
@@ -39,6 +39,7 @@ limitations under the License.
 
 #include <linux/nl80211.h>
 #include <linux/ieee80211.h>
+#include <linux/mac80211_hwsim.h>
 #include <libubox/uloop.h>
 
 #include "ucode/module.h"
@@ -374,7 +375,7 @@ static const uc_nl_nested_spec_t nl80211_nan_func_nla = {
 	}
 };
 
-static const uc_nl_nested_spec_t nl80211_peer_measurements_peers_req_data_ftm_nla = {
+static const uc_nl_nested_spec_t nl80211_peer_measurements_type_ftm_nla = {
 	.headsize = 0,
 	.nattrs = 13,
 	.attrs = {
@@ -398,7 +399,7 @@ static const uc_nl_nested_spec_t nl80211_peer_measurements_peers_req_data_nla =
 	.headsize = 0,
 	.nattrs = 2,
 	.attrs = {
-		{ NL80211_PMSR_TYPE_FTM, "ftm", DT_NESTED, 0, &nl80211_peer_measurements_peers_req_data_ftm_nla },
+		{ NL80211_PMSR_TYPE_FTM, "ftm", DT_NESTED, 0, &nl80211_peer_measurements_type_ftm_nla },
 		{ NL80211_PMSR_REQ_ATTR_GET_AP_TSF, "get_ap_tsf", DT_FLAG, 0, NULL },
 	}
 };
@@ -422,13 +423,34 @@ static const uc_nl_nested_spec_t nl80211_peer_measurements_peers_chan_nla = {
 	}
 };
 
+static const uc_nl_nested_spec_t nl80211_peer_measurements_peers_resp_data_nla = {
+	.headsize = 0,
+	.nattrs = 1,
+	.attrs = {
+		{ NL80211_PMSR_TYPE_FTM, "ftm", DT_NESTED, 0, &nl80211_peer_measurements_type_ftm_nla },
+	}
+};
+
+static const uc_nl_nested_spec_t nl80211_peer_measurements_peers_resp_nla = {
+	.headsize = 0,
+	.nattrs = 5,
+	.attrs = {
+		{ NL80211_PMSR_RESP_ATTR_STATUS, "status", DT_U32, 0, NULL },
+		{ NL80211_PMSR_RESP_ATTR_HOST_TIME, "host_time", DT_U64, 0, NULL },
+		{ NL80211_PMSR_RESP_ATTR_AP_TSF, "ap_tsf", DT_U64, 0, NULL },
+		{ NL80211_PMSR_RESP_ATTR_FINAL, "final", DT_FLAG, 0, NULL },
+		{ NL80211_PMSR_RESP_ATTR_DATA, "data", DT_NESTED, 0, &nl80211_peer_measurements_peers_resp_data_nla },
+	}
+};
+
 static const uc_nl_nested_spec_t nl80211_peer_measurements_peers_nla = {
 	.headsize = 0,
-	.nattrs = 3,
+	.nattrs = 4,
 	.attrs = {
 		{ NL80211_PMSR_PEER_ATTR_ADDR, "addr", DT_LLADDR, 0, NULL },
 		{ NL80211_PMSR_PEER_ATTR_REQ, "req", DT_NESTED, 0, &nl80211_peer_measurements_peers_req_nla },
-		{ NL80211_PMSR_PEER_ATTR_CHAN, "chan", DT_NESTED, 0, &nl80211_peer_measurements_peers_chan_nla }
+		{ NL80211_PMSR_PEER_ATTR_CHAN, "chan", DT_NESTED, 0, &nl80211_peer_measurements_peers_chan_nla },
+		{ NL80211_PMSR_PEER_ATTR_RESP, "resp", DT_NESTED, 0, &nl80211_peer_measurements_peers_resp_nla }
 	}
 };
 
@@ -965,6 +987,78 @@ static const uc_nl_nested_spec_t nl80211_msg = {
 	}
 };
 
+static const uc_nl_nested_spec_t hwsim_tx_info_struct = {
+	.headsize = sizeof(struct hwsim_tx_rate),
+	.nattrs = 2,
+	.attrs = {
+		{ NLA_UNSPEC, "idx", DT_S8, 0, MEMBER(hwsim_tx_rate, idx) },
+		{ NLA_UNSPEC, "count", DT_U8, 0, MEMBER(hwsim_tx_rate, count) },
+	}
+};
+
+static const uc_nl_nested_spec_t hwsim_tx_info_flags_struct = {
+	.headsize = sizeof(struct hwsim_tx_rate_flag),
+	.nattrs = 2,
+	.attrs = {
+		{ NLA_UNSPEC, "idx", DT_S8, 0, MEMBER(hwsim_tx_rate_flag, idx) },
+		{ NLA_UNSPEC, "flags", DT_U16, 0, MEMBER(hwsim_tx_rate_flag, flags) },
+	}
+};
+
+static const uc_nl_nested_spec_t hwsim_pmsr_support_nla = {
+	.headsize = 0,
+	.nattrs = 5,
+	.attrs = {
+		{ NL80211_PMSR_ATTR_MAX_PEERS, "max_peers", DT_U32, 0, NULL },
+		{ NL80211_PMSR_ATTR_REPORT_AP_TSF, "report_ap_tsf", DT_FLAG, 0, NULL },
+		{ NL80211_PMSR_ATTR_RANDOMIZE_MAC_ADDR, "randomize_mac_addr", DT_FLAG, 0, NULL },
+		{ NL80211_PMSR_ATTR_TYPE_CAPA, "type_capa", DT_U32, 0, NULL },
+		{ NL80211_PMSR_ATTR_PEERS, "peers", DT_NESTED, DF_MULTIPLE|DF_AUTOIDX, &nl80211_peer_measurements_peers_nla },
+	}
+};
+
+static const uc_nl_nested_spec_t hwsim_pmsr_request_nla = {
+	.headsize = 0,
+	.nattrs = 1,
+	.attrs = {
+		{ NL80211_ATTR_PEER_MEASUREMENTS, "peer_measurements", DT_NESTED, 0, &nl80211_peer_measurements_nla },
+	}
+};
+
+static const uc_nl_nested_spec_t hwsim_msg = {
+	.headsize = 0,
+	.nattrs = 27,
+	.attrs = {
+		{ HWSIM_ATTR_ADDR_RECEIVER, "addr_receiver", DT_LLADDR, 0, NULL },
+		{ HWSIM_ATTR_ADDR_TRANSMITTER, "addr_transmitter", DT_LLADDR, 0, NULL },
+		{ HWSIM_ATTR_FRAME, "frame", DT_STRING, DF_BINARY, NULL },
+		{ HWSIM_ATTR_FLAGS, "flags", DT_U32, 0, NULL },
+		{ HWSIM_ATTR_RX_RATE, "rx_rate", DT_U32, 0, NULL },
+		{ HWSIM_ATTR_SIGNAL, "signal", DT_U32, 0, NULL },
+		{ HWSIM_ATTR_TX_INFO, "tx_info", DT_NESTED, DF_ARRAY, &hwsim_tx_info_struct },
+		{ HWSIM_ATTR_COOKIE, "cookie", DT_U64, 0, NULL },
+		{ HWSIM_ATTR_CHANNELS, "channels", DT_U32, 0, NULL },
+		{ HWSIM_ATTR_RADIO_ID, "radio_id", DT_U32, 0, NULL },
+		{ HWSIM_ATTR_REG_HINT_ALPHA2, "reg_hint_alpha2", DT_STRING, DF_BINARY, NULL },
+		{ HWSIM_ATTR_REG_CUSTOM_REG, "reg_custom_reg", DT_U32, 0, NULL },
+		{ HWSIM_ATTR_REG_STRICT_REG, "reg_strict_reg", DT_FLAG, 0, NULL },
+		{ HWSIM_ATTR_SUPPORT_P2P_DEVICE, "support_p2p_device", DT_FLAG, 0, NULL },
+		{ HWSIM_ATTR_USE_CHANCTX, "use_chanctx", DT_FLAG, 0, NULL },
+		{ HWSIM_ATTR_DESTROY_RADIO_ON_CLOSE, "destroy_radio_on_close", DT_FLAG, 0, NULL },
+		{ HWSIM_ATTR_RADIO_NAME, "radio_name", DT_STRING, DF_BINARY, NULL },
+		{ HWSIM_ATTR_NO_VIF, "no_vif", DT_FLAG, 0, NULL },
+		{ HWSIM_ATTR_FREQ, "freq", DT_U32, 0, NULL },
+		{ HWSIM_ATTR_TX_INFO_FLAGS, "tx_info_flags", DT_NESTED, DF_ARRAY, &hwsim_tx_info_flags_struct },
+		{ HWSIM_ATTR_PERM_ADDR, "perm_addr", DT_LLADDR, 0, NULL },
+		{ HWSIM_ATTR_IFTYPE_SUPPORT, "iftype_support", DT_U32, 0, NULL },
+		{ HWSIM_ATTR_CIPHER_SUPPORT, "cipher_support", DT_U32, DF_ARRAY, NULL },
+		{ HWSIM_ATTR_MLO_SUPPORT, "mlo_support", DT_FLAG, 0, NULL },
+		{ HWSIM_ATTR_PMSR_SUPPORT, "pmsr_support", DT_NESTED, 0, &hwsim_pmsr_support_nla },
+		{ HWSIM_ATTR_PMSR_REQUEST, "pmsr_request", DT_NESTED, 0, &hwsim_pmsr_request_nla },
+		{ HWSIM_ATTR_PMSR_RESULT, "pmsr_result", DT_NESTED, 0, &hwsim_pmsr_support_nla },
+	}
+};
+
 
 static bool
 nla_check_len(struct nlattr *nla, size_t sz)
@@ -1921,6 +2015,7 @@ typedef struct {
 	uc_vm_t *vm;
 	uc_value_t *res;
 	bool merge;
+	const uc_nl_nested_spec_t *spec;
 } request_state_t;
 
 
@@ -2023,7 +2118,7 @@ cb_reply(struct nl_msg *msg, void *arg)
 
 	rv = uc_nl_convert_attrs(msg,
 		genlmsg_attrdata(gnlh, 0), genlmsg_attrlen(gnlh, 0),
-		0, nl80211_msg.attrs, nl80211_msg.nattrs, s->vm, o);
+		0, s->spec->attrs, s->spec->nattrs, s->vm, o);
 
 	if (rv) {
 		if (hdr->nlmsg_flags & NLM_F_MULTI) {
@@ -2474,7 +2569,7 @@ uc_nl_request(uc_vm_t *vm, size_t nargs)
 	uint16_t flagval = 0;
 	struct nl_msg *msg;
 	struct nl_cb *cb;
-	int ret, id;
+	int ret, id, cid;
 
 	if (ucv_type(cmd) != UC_INTEGER || ucv_int64_get(cmd) < 0 ||
 	    (flags != NULL && ucv_type(flags) != UC_INTEGER) ||
@@ -2496,25 +2591,30 @@ uc_nl_request(uc_vm_t *vm, size_t nargs)
 	if (!msg)
 		err_return(NLE_NOMEM, NULL);
 
-	id = uc_nl_find_family_id("nl80211");
+	cid = ucv_int64_get(cmd);
+
+	if (cid >= HWSIM_CMD_OFFSET) {
+		id = uc_nl_find_family_id("MAC80211_HWSIM");
+		cid -= HWSIM_CMD_OFFSET;
+		st.spec = &hwsim_msg;
+	}
+	else {
+		id = uc_nl_find_family_id("nl80211");
+		st.merge = (cid == NL80211_CMD_GET_WIPHY);
+		st.spec = &nl80211_msg;
+	}
 
 	if (id < 0)
 		err_return(-id, NULL);
 
-	genlmsg_put(msg, 0, 0, id, 0, flagval, ucv_int64_get(cmd), 0);
+	genlmsg_put(msg, 0, 0, id, 0, flagval, cid, 0);
 
-	if (!uc_nl_parse_attrs(msg, nlmsg_data(nlmsg_hdr(msg)), nl80211_msg.attrs, nl80211_msg.nattrs, vm, payload)) {
+	if (!uc_nl_parse_attrs(msg, nlmsg_data(nlmsg_hdr(msg)), st.spec->attrs, st.spec->nattrs, vm, payload)) {
 		nlmsg_free(msg);
 
 		return NULL;
 	}
 
-	switch (ucv_int64_get(cmd)) {
-	case NL80211_CMD_GET_WIPHY:
-		st.merge = true;
-		break;
-	}
-
 	cb = nl_cb_alloc(NL_CB_DEFAULT);
 
 	if (!cb) {
@@ -2538,7 +2638,7 @@ uc_nl_request(uc_vm_t *vm, size_t nargs)
 	nl_cb_put(cb);
 
 	if (ret < 0)
-		err_return(nl_syserr2nlerr(ret), NULL);
+		err_return(ret, NULL);
 
 	switch (st.state) {
 	case STATE_REPLIED:
@@ -2804,6 +2904,18 @@ register_constants(uc_vm_t *vm, uc_value_t *scope)
 	ADD_CONST(NL80211_CMD_TDLS_CHANNEL_SWITCH);
 	ADD_CONST(NL80211_CMD_TDLS_CANCEL_CHANNEL_SWITCH);
 
+	ADD_CONST(HWSIM_CMD_REGISTER),
+	ADD_CONST(HWSIM_CMD_FRAME),
+	ADD_CONST(HWSIM_CMD_TX_INFO_FRAME),
+	ADD_CONST(HWSIM_CMD_NEW_RADIO),
+	ADD_CONST(HWSIM_CMD_DEL_RADIO),
+	ADD_CONST(HWSIM_CMD_GET_RADIO),
+	ADD_CONST(HWSIM_CMD_ADD_MAC_ADDR),
+	ADD_CONST(HWSIM_CMD_DEL_MAC_ADDR),
+	ADD_CONST(HWSIM_CMD_START_PMSR),
+	ADD_CONST(HWSIM_CMD_ABORT_PMSR),
+	ADD_CONST(HWSIM_CMD_REPORT_PMSR),
+
 	ADD_CONST(NL80211_IFTYPE_ADHOC);
 	ADD_CONST(NL80211_IFTYPE_STATION);
 	ADD_CONST(NL80211_IFTYPE_AP);