pimd: refactor pim_sock_read to be used with unicast bsr msgs

Signed-off-by: Jafar Al-Gharaibeh <[email protected]>
FRRouting · Aug 29, 2024 · 2906368 · 2906368
1 parent f790831
commit 2906368
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Showing 3 changed files with 42 additions and 92 deletions.
diff --git a/pimd/pim_bsm.c b/pimd/pim_bsm.c
@@ -258,66 +258,11 @@ static inline void pim_bs_timer_restart(struct bsm_scope *scope, int bs_timeout)
 static void bsm_unicast_sock_read(struct event *t)
 {
 	struct bsm_scope *scope = EVENT_ARG(t);
-	struct sockaddr_storage from;
-	struct sockaddr_storage to;
-	socklen_t fromlen = sizeof(from);
-	socklen_t tolen = sizeof(to);
-	ifindex_t ifindex = 0;
-	struct interface *ifp;
-	uint8_t buf[PIM_PIM_BUFSIZE_READ];
-	int len, i;
+
+	pim_sock_read_helper(scope->unicast_sock, scope->pim, false);
 
 	event_add_read(router->master, bsm_unicast_sock_read, scope,
 		       scope->unicast_sock, &scope->unicast_read);
-
-	for (i = 0; i < router->packet_process; i++) {
-		pim_sgaddr sg;
-
-		len = pim_socket_recvfromto(scope->unicast_sock, buf,
-					    sizeof(buf), &from, &fromlen, &to,
-					    &tolen, &ifindex);
-		if (len < 0) {
-			if (errno == EINTR)
-				continue;
-			if (errno == EWOULDBLOCK || errno == EAGAIN)
-				break;
-
-			if (PIM_DEBUG_PIM_PACKETS)
-				zlog_debug("Received errno: %d %s", errno,
-					   safe_strerror(errno));
-			break;
-		}
-
-#if PIM_IPV == 4
-		sg.src = ((struct sockaddr_in *)&from)->sin_addr;
-		sg.grp = ((struct sockaddr_in *)&to)->sin_addr;
-#else
-		sg.src = ((struct sockaddr_in6 *)&from)->sin6_addr;
-		sg.grp = ((struct sockaddr_in6 *)&to)->sin6_addr;
-#endif
-
-		/*
-		 * What?  So with vrf's the incoming packet is received
-		 * on the vrf interface but recvfromto above returns
-		 * the right ifindex, so just use it.  We know
-		 * it's the right interface because we bind to it
-		 */
-		ifp = if_lookup_by_index(ifindex, scope->pim->vrf->vrf_id);
-		if (!ifp) {
-			zlog_warn("Received incoming PIM packet on unknown ifindex %d",
-				  ifindex);
-			break;
-		}
-
-		int fail = pim_pim_packet(ifp, buf, len, sg, false);
-
-		if (fail) {
-			if (PIM_DEBUG_PIM_PACKETS)
-				zlog_debug("%s: pim_pim_packet() return=%d",
-					   __func__, fail);
-			break;
-		}
-	}
 }
 
 void pim_bsm_proc_init(struct pim_instance *pim)

diff --git a/pimd/pim_pim.c b/pimd/pim_pim.c
@@ -13,7 +13,6 @@
 #include "network.h"
 
 #include "pimd.h"
-#include "pim_instance.h"
 #include "pim_pim.h"
 #include "pim_time.h"
 #include "pim_iface.h"
@@ -355,30 +354,19 @@ int pim_pim_packet(struct interface *ifp, uint8_t *buf, size_t len,
 	}
 }
 
-static void pim_sock_read_on(struct interface *ifp);
-
-static void pim_sock_read(struct event *t)
+int pim_sock_read_helper(int fd, struct pim_instance *pim, bool is_mcast)
 {
-	struct interface *ifp, *orig_ifp;
-	struct pim_interface *pim_ifp;
-	int fd;
+	struct interface *ifp = NULL;
 	struct sockaddr_storage from;
 	struct sockaddr_storage to;
 	socklen_t fromlen = sizeof(from);
 	socklen_t tolen = sizeof(to);
 	uint8_t buf[PIM_PIM_BUFSIZE_READ];
 	int len;
 	ifindex_t ifindex = -1;
-	int result = -1; /* defaults to bad */
-	static long long count = 0;
-	int cont = 1;
-
-	orig_ifp = ifp = EVENT_ARG(t);
-	fd = EVENT_FD(t);
-
-	pim_ifp = ifp->info;
+	int i;
 
-	while (cont) {
+	for (i = 0; i < router->packet_process; i++) {
 		pim_sgaddr sg;
 
 		len = pim_socket_recvfromto(fd, buf, sizeof(buf), &from,
@@ -392,7 +380,7 @@ static void pim_sock_read(struct event *t)
 			if (PIM_DEBUG_PIM_PACKETS)
 				zlog_debug("Received errno: %d %s", errno,
 					   safe_strerror(errno));
-			goto done;
+			return -1;
 		}
 
 		/*
@@ -401,14 +389,21 @@ static void pim_sock_read(struct event *t)
 		 * the right ifindex, so just use it.  We know
 		 * it's the right interface because we bind to it
 		 */
-		ifp = if_lookup_by_index(ifindex, pim_ifp->pim->vrf->vrf_id);
-		if (!ifp || !ifp->info) {
+		if (pim != NULL)
+			ifp = if_lookup_by_index(ifindex, pim->vrf->vrf_id);
+
+		/*
+		 * unicast BSM pkts (C-RP) may arrive on non pim interfaces
+		 * mcast pkts are only expected in pim interfaces
+		 */
+		if (!ifp || (is_mcast && !ifp->info)) {
 			if (PIM_DEBUG_PIM_PACKETS)
-				zlog_debug(
-					"%s: Received incoming pim packet on interface(%s:%d) not yet configured for pim",
-					__func__, ifp ? ifp->name : "Unknown",
-					ifindex);
-			goto done;
+				zlog_debug("%s: Received incoming pim packet on interface(%s:%d)%s",
+					   __func__,
+					   ifp ? ifp->name : "Unknown", ifindex,
+					   is_mcast ? " not yet configured for pim"
+						    : "");
+			return -1;
 		}
 #if PIM_IPV == 4
 		sg.src = ((struct sockaddr_in *)&from)->sin_addr;
@@ -418,27 +413,34 @@ static void pim_sock_read(struct event *t)
 		sg.grp = ((struct sockaddr_in6 *)&to)->sin6_addr;
 #endif
 
-		int fail = pim_pim_packet(ifp, buf, len, sg, true);
+		int fail = pim_pim_packet(ifp, buf, len, sg, is_mcast);
 		if (fail) {
 			if (PIM_DEBUG_PIM_PACKETS)
 				zlog_debug("%s: pim_pim_packet() return=%d",
 					   __func__, fail);
-			goto done;
+			return -1;
 		}
-
-		count++;
-		if (count % router->packet_process == 0)
-			cont = 0;
 	}
+	return 0;
+}
+
+static void pim_sock_read_on(struct interface *ifp);
+
+static void pim_sock_read(struct event *t)
+{
+	struct interface *ifp;
+	struct pim_interface *pim_ifp;
+	int fd;
 
-	result = 0; /* good */
+	ifp = EVENT_ARG(t);
+	fd = EVENT_FD(t);
 
-done:
-	pim_sock_read_on(orig_ifp);
+	pim_ifp = ifp->info;
 
-	if (result) {
+	if (pim_sock_read_helper(fd, pim_ifp->pim, true) == 0)
 		++pim_ifp->pim_ifstat_hello_recvfail;
-	}
+
+	pim_sock_read_on(ifp);
 }
 
 static void pim_sock_read_on(struct interface *ifp)

diff --git a/pimd/pim_pim.h b/pimd/pim_pim.h
@@ -10,6 +10,7 @@
 #include <zebra.h>
 
 #include "if.h"
+#include "pim_instance.h"
 
 #define PIM_PIM_BUFSIZE_READ  (20000)
 #define PIM_PIM_BUFSIZE_WRITE (20000)
@@ -48,4 +49,6 @@ int pim_msg_send(int fd, pim_addr src, pim_addr dst, uint8_t *pim_msg,
 		 int pim_msg_size, struct interface *ifp);
 
 int pim_hello_send(struct interface *ifp, uint16_t holdtime);
+
+int pim_sock_read_helper(int fd, struct pim_instance *pim, bool is_mcast);
 #endif /* PIM_PIM_H */