recipes-wifi/hostapd/files/patches-2.10.3/0002-ctrl_iface-MLO-introduce-MLD-level-socket.patch

From 631a48c1a241bf9515d296eeea5d6060bef96cff Mon Sep 17 00:00:00 2001
From: Aditya Kumar Singh <quic_adisi@quicinc.com>
Date: Tue, 23 Apr 2024 11:01:24 +0530
Subject: [PATCH 002/126] ctrl_iface: MLO: introduce MLD level socket

With MLO, each link have socket created with "<ifname>_link<link id>" under
the control interface directory.

Introduce a MLD level socket - "<ifname>" as well under the same control
interface directory. This socket can be used to pass the command to its
partner links directly instead of using the link level socket. Link ID
needs to be passed with the command.

The structure of the command is -
 "<COMMAND APPLICABALE FOR THE LINK> LINKID <link id>"

Directory looks something like this -
  $ ls /var/run/hostapd/
    wlan0
    wlan0_link0
    wlan0_link1

wlan0 here is the MLD level socket. Rest are each link level.

This would also help to maintain backwards compatibility with applications
which looks for <ifname> under the control interface directory.`

Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
---
 hostapd/ctrl_iface.c | 335 +++++++++++++++++++++++++++++++++++++++++++
 hostapd/ctrl_iface.h |   4 +
 hostapd/main.c       |   5 +
 src/ap/hostapd.c     |  11 ++
 src/ap/hostapd.h     |   6 +
 5 files changed, 361 insertions(+)

diff --git a/hostapd/ctrl_iface.c b/hostapd/ctrl_iface.c
index 3fa33be7a..5fe29147f 100644
--- a/hostapd/ctrl_iface.c
+++ b/hostapd/ctrl_iface.c
@@ -4682,6 +4682,341 @@ done:
 }
 
 
+#ifdef CONFIG_IEEE80211BE
+#ifndef CONFIG_CTRL_IFACE_UDP
+static int hostapd_mld_ctrl_iface_attach(struct hostapd_mld *mld,
+					 struct sockaddr_storage *from,
+					 socklen_t fromlen, const char *input)
+{
+	return ctrl_iface_attach(&mld->ctrl_dst, from, fromlen, input);
+}
+
+
+static int hostapd_mld_ctrl_iface_detach(struct hostapd_mld *mld,
+					 struct sockaddr_storage *from,
+					 socklen_t fromlen)
+{
+	return ctrl_iface_detach(&mld->ctrl_dst, from, fromlen);
+}
+
+
+static int hostapd_mld_ctrl_iface_receive_process(struct hostapd_mld *mld,
+						  char *buf, char *reply,
+						  int reply_size,
+						  struct sockaddr_storage *from,
+						  socklen_t fromlen)
+{
+	struct hostapd_data *link_hapd, *link_itr;
+	int reply_len, link_id = -1;
+	char *link_cmd;
+	bool found = false;
+
+	os_memcpy(reply, "OK\n", 3);
+	reply_len = 3;
+
+	/* Check if link id is provided in the command or not */
+	link_cmd = os_strstr(buf, "LINKID");
+	if (link_cmd) {
+		/* Trim the link id part now */
+		*(link_cmd - 1) = '\0';
+
+		link_cmd += 7;
+		link_id = atoi(link_cmd);
+
+		if (link_id < 0 || link_id >= 15) {
+			os_memcpy(reply, "INVALID LINK ID\n", 16);
+			reply_len = 16;
+			return reply_len;
+		}
+
+		link_hapd = mld->fbss;
+		if (!link_hapd) {
+			os_memcpy(reply, "NO LINKS ACTIVE\n", 16);
+			reply_len = 16;
+			return reply_len;
+		}
+
+		for_each_mld_link(link_itr, link_hapd) {
+			if (link_itr->mld_link_id == link_id) {
+				found = true;
+				break;
+			}
+		}
+
+		if (!found) {
+			os_memcpy(reply, "FAIL\n", 5);
+			reply_len = 5;
+			return reply_len;
+		}
+
+		link_hapd = link_itr;
+	} else {
+		link_hapd = mld->fbss;
+	}
+
+	if (os_strcmp(buf, "PING") == 0) {
+		os_memcpy(reply, "PONG\n", 5);
+		reply_len = 5;
+	} else if (os_strcmp(buf, "ATTACH") == 0) {
+		if (hostapd_mld_ctrl_iface_attach(mld, from, fromlen, NULL))
+			reply_len = -1;
+	} else if (os_strncmp(buf, "ATTACH ", 7) == 0) {
+		if (hostapd_mld_ctrl_iface_attach(mld, from, fromlen, buf + 7))
+			reply_len = -1;
+	} else if (os_strcmp(buf, "DETACH") == 0) {
+		if (hostapd_mld_ctrl_iface_detach(mld, from, fromlen))
+			reply_len = -1;
+	} else {
+		if (link_id == -1)
+			wpa_printf(MSG_DEBUG, "Link ID not provided, using first link BSS (if available)");
+
+		if (!link_hapd)
+			reply_len = -1;
+		else
+			reply_len =
+				hostapd_ctrl_iface_receive_process(link_hapd, buf,
+								   reply, reply_size,
+								   from, fromlen);
+	}
+
+	if (reply_len < 0) {
+		os_memcpy(reply, "FAIL\n", 5);
+		reply_len = 5;
+	}
+
+	return reply_len;
+}
+
+
+static void hostapd_mld_ctrl_iface_receive(int sock, void *eloop_ctx,
+					   void *sock_ctx)
+{
+	struct hostapd_mld *mld = eloop_ctx;
+	char buf[4096];
+	int res;
+	struct sockaddr_storage from;
+	socklen_t fromlen = sizeof(from);
+	char *reply, *pos = buf;
+	const int reply_size = 4096;
+	int reply_len;
+	int level = MSG_DEBUG;
+
+	res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
+		       (struct sockaddr *) &from, &fromlen);
+	if (res < 0) {
+		wpa_printf(MSG_ERROR, "recvfrom(mld ctrl_iface): %s",
+			   strerror(errno));
+		return;
+	}
+	buf[res] = '\0';
+
+	reply = os_malloc(reply_size);
+	if (reply == NULL) {
+		if (sendto(sock, "FAIL\n", 5, 0, (struct sockaddr *) &from,
+			   fromlen) < 0) {
+			wpa_printf(MSG_DEBUG, "MLD CTRL: sendto failed: %s",
+				   strerror(errno));
+		}
+		return;
+	}
+
+	if (os_strcmp(pos, "PING") == 0)
+		level = MSG_EXCESSIVE;
+
+	wpa_hexdump_ascii(level, "RX MLD ctrl_iface", pos, res);
+
+	reply_len = hostapd_mld_ctrl_iface_receive_process(mld, pos,
+							   reply, reply_size,
+							   &from, fromlen);
+
+	if (sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
+		   fromlen) < 0) {
+		wpa_printf(MSG_DEBUG, "MLD CTRL: sendto failed: %s",
+			   strerror(errno));
+	}
+	os_free(reply);
+}
+
+
+static char * hostapd_mld_ctrl_iface_path(struct hostapd_mld *mld)
+{
+	char *buf;
+	size_t len;
+
+	if (!mld->ctrl_interface)
+		return NULL;
+
+	len = os_strlen(mld->ctrl_interface) + os_strlen(mld->name) + 2;
+
+	buf = os_malloc(len);
+	if (buf == NULL)
+		return NULL;
+
+	os_snprintf(buf, len, "%s/%s", mld->ctrl_interface, mld->name);
+	buf[len - 1] = '\0';
+	return buf;
+}
+#endif /* !CONFIG_CTRL_IFACE_UDP */
+
+
+int hostapd_mld_ctrl_iface_init(struct hostapd_mld *mld)
+{
+#ifndef CONFIG_CTRL_IFACE_UDP
+	struct sockaddr_un addr;
+	int s = -1;
+	char *fname = NULL;
+
+	if (!mld)
+		return -1;
+
+	if (mld->ctrl_sock > -1) {
+		wpa_printf(MSG_DEBUG, "MLD %s ctrl_iface already exists!",
+			   mld->name);
+		return 0;
+	}
+
+	dl_list_init(&mld->ctrl_dst);
+
+	if (mld->ctrl_interface == NULL)
+		return 0;
+
+	if (mkdir(mld->ctrl_interface, S_IRWXU | S_IRWXG) < 0) {
+		if (errno == EEXIST) {
+			wpa_printf(MSG_DEBUG, "Using existing control "
+				   "interface directory.");
+		} else {
+			wpa_printf(MSG_ERROR, "mkdir[ctrl_interface]: %s",
+				   strerror(errno));
+			goto fail;
+		}
+	}
+
+	if (os_strlen(mld->ctrl_interface) + 1 +
+	    os_strlen(mld->name) >= sizeof(addr.sun_path))
+		goto fail;
+
+	s = socket(PF_UNIX, SOCK_DGRAM, 0);
+	if (s < 0) {
+		wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
+		goto fail;
+	}
+
+	os_memset(&addr, 0, sizeof(addr));
+#ifdef __FreeBSD__
+	addr.sun_len = sizeof(addr);
+#endif /* __FreeBSD__ */
+	addr.sun_family = AF_UNIX;
+
+	fname = hostapd_mld_ctrl_iface_path(mld);
+	if (fname == NULL)
+		goto fail;
+
+	os_strlcpy(addr.sun_path, fname, sizeof(addr.sun_path));
+
+	wpa_printf(MSG_DEBUG, "Setting up MLD %s ctrl_iface", mld->name);
+
+	if (bind(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
+		wpa_printf(MSG_DEBUG, "ctrl_iface bind(PF_UNIX) failed: %s",
+			   strerror(errno));
+		if (connect(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
+			wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
+				   " allow connections - assuming it was left"
+				   "over from forced program termination");
+			if (unlink(fname) < 0) {
+				wpa_printf(MSG_ERROR,
+					   "Could not unlink existing ctrl_iface socket '%s': %s",
+					   fname, strerror(errno));
+				goto fail;
+			}
+			if (bind(s, (struct sockaddr *) &addr, sizeof(addr)) <
+			    0) {
+				wpa_printf(MSG_ERROR,
+					   "hostapd-ctrl-iface: bind(PF_UNIX): %s",
+					   strerror(errno));
+				goto fail;
+			}
+			wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
+				   "ctrl_iface socket '%s'", fname);
+		} else {
+			wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
+				   "be in use - cannot override it");
+			wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
+				   "not used anymore", fname);
+			os_free(fname);
+			fname = NULL;
+			goto fail;
+		}
+	}
+
+	if (chmod(fname, S_IRWXU | S_IRWXG) < 0) {
+		wpa_printf(MSG_ERROR, "chmod[ctrl_interface/ifname]: %s",
+			   strerror(errno));
+		goto fail;
+	}
+	os_free(fname);
+
+	mld->ctrl_sock = s;
+
+	if (eloop_register_read_sock(s, hostapd_mld_ctrl_iface_receive, mld,
+				     NULL) < 0)
+		return -1;
+
+	return 0;
+
+fail:
+	if (s >= 0)
+		close(s);
+	if (fname) {
+		unlink(fname);
+		os_free(fname);
+	}
+	return -1;
+#endif /* !CONFIG_CTRL_IFACE_UDP */
+	return 0;
+}
+
+
+void hostapd_mld_ctrl_iface_deinit(struct hostapd_mld *mld)
+{
+#ifndef CONFIG_CTRL_IFACE_UDP
+	struct wpa_ctrl_dst *dst, *prev;
+
+	if (mld->ctrl_sock > -1) {
+		char *fname;
+		eloop_unregister_read_sock(mld->ctrl_sock);
+		close(mld->ctrl_sock);
+		mld->ctrl_sock = -1;
+
+		fname = hostapd_mld_ctrl_iface_path(mld);
+		if (fname)
+			unlink(fname);
+		os_free(fname);
+
+		if (mld->ctrl_interface &&
+		    rmdir(mld->ctrl_interface) < 0) {
+			if (errno == ENOTEMPTY) {
+				wpa_printf(MSG_DEBUG, "MLD Control interface "
+					   "directory not empty - leaving it "
+					   "behind");
+			} else {
+				wpa_printf(MSG_ERROR,
+					   "rmdir[ctrl_interface=%s]: %s",
+					   mld->ctrl_interface,
+					   strerror(errno));
+			}
+		}
+	}
+
+	dl_list_for_each_safe(dst, prev, &mld->ctrl_dst, struct wpa_ctrl_dst,
+			      list)
+		os_free(dst);
+#endif /* !CONFIG_CTRL_IFACE_UDP */
+
+	os_free(mld->ctrl_interface);
+}
+#endif /* CONFIG_IEEE80211BE */
+
+
 #ifndef CONFIG_CTRL_IFACE_UDP
 static char * hostapd_ctrl_iface_path(struct hostapd_data *hapd)
 {
diff --git a/hostapd/ctrl_iface.h b/hostapd/ctrl_iface.h
index 3341a66bd..ec5a95be7 100644
--- a/hostapd/ctrl_iface.h
+++ b/hostapd/ctrl_iface.h
@@ -14,6 +14,10 @@ int hostapd_ctrl_iface_init(struct hostapd_data *hapd);
 void hostapd_ctrl_iface_deinit(struct hostapd_data *hapd);
 int hostapd_global_ctrl_iface_init(struct hapd_interfaces *interface);
 void hostapd_global_ctrl_iface_deinit(struct hapd_interfaces *interface);
+#ifdef CONFIG_IEEE80211BE
+int hostapd_mld_ctrl_iface_init(struct hostapd_mld *mld);
+void hostapd_mld_ctrl_iface_deinit(struct hostapd_mld *mld);
+#endif /* CONFIG_IEEE80211BE */
 #else /* CONFIG_NO_CTRL_IFACE */
 static inline int hostapd_ctrl_iface_init(struct hostapd_data *hapd)
 {
diff --git a/hostapd/main.c b/hostapd/main.c
index 00e02bb03..aa1f69812 100644
--- a/hostapd/main.c
+++ b/hostapd/main.c
@@ -748,6 +748,7 @@ static void hostapd_global_cleanup_mld(struct hapd_interfaces *interfaces)
 		if (!interfaces->mld[i])
 			continue;
 
+		interfaces->mld_ctrl_iface_deinit(interfaces->mld[i]);
 		os_free(interfaces->mld[i]);
 		interfaces->mld[i] = NULL;
 	}
@@ -793,6 +794,10 @@ int main(int argc, char *argv[])
 	interfaces.global_iface_path = NULL;
 	interfaces.global_iface_name = NULL;
 	interfaces.global_ctrl_sock = -1;
+#ifdef CONFIG_IEEE80211BE
+	interfaces.mld_ctrl_iface_init = hostapd_mld_ctrl_iface_init;
+	interfaces.mld_ctrl_iface_deinit = hostapd_mld_ctrl_iface_deinit;
+#endif /* CONFIG_IEEE80211BE */
 	dl_list_init(&interfaces.global_ctrl_dst);
 #ifdef CONFIG_ETH_P_OUI
 	dl_list_init(&interfaces.eth_p_oui);
diff --git a/src/ap/hostapd.c b/src/ap/hostapd.c
index c819c30cf..36d48ae09 100644
--- a/src/ap/hostapd.c
+++ b/src/ap/hostapd.c
@@ -3093,9 +3093,18 @@ static void hostapd_bss_setup_multi_link(struct hostapd_data *hapd,
 
 	os_strlcpy(mld->name, conf->iface, sizeof(conf->iface));
 	dl_list_init(&mld->links);
+	mld->ctrl_sock = -1;
+	mld->ctrl_interface = os_strdup(hapd->conf->ctrl_interface);
 
 	wpa_printf(MSG_DEBUG, "AP MLD %s created", mld->name);
 
+	/*
+	 * Initialize MLD control interfaces early to allow external monitoring of
+	 * link setup operations.
+	 */
+	if (interfaces->mld_ctrl_iface_init(mld))
+		goto fail;
+
 	hapd->mld = mld;
 	hostapd_mld_ref_inc(mld);
 	hostapd_bss_alloc_link_id(hapd);
@@ -3155,6 +3164,8 @@ static void hostapd_cleanup_unused_mlds(struct hapd_interfaces *interfaces)
 		if (!remove && !forced_remove)
 			continue;
 
+		interfaces->mld_ctrl_iface_deinit(mld);
+
 		wpa_printf(MSG_DEBUG, "AP MLD %s: Freed%s", mld->name,
 			   forced_remove ? " (forced)" : "");
 		os_free(mld);
diff --git a/src/ap/hostapd.h b/src/ap/hostapd.h
index 34a665562..2ef63e5f2 100644
--- a/src/ap/hostapd.h
+++ b/src/ap/hostapd.h
@@ -97,6 +97,8 @@ struct hapd_interfaces {
 #ifdef CONFIG_IEEE80211BE
 	struct hostapd_mld **mld;
 	size_t mld_count;
+	int (*mld_ctrl_iface_init)(struct hostapd_mld *mld);
+	void (*mld_ctrl_iface_deinit)(struct hostapd_mld *mld);
 #endif /* CONFIG_IEEE80211BE */
 };
 
@@ -519,6 +521,10 @@ struct hostapd_mld {
 
 	struct hostapd_data *fbss;
 	struct dl_list links; /* List head of all affiliated links */
+
+	int ctrl_sock;
+	struct dl_list ctrl_dst;
+	char *ctrl_interface; /* directory for UNIX domain sockets */
 };
 
 #define HOSTAPD_MLD_MAX_REF_COUNT      0xFF
-- 
2.18.0