[Devel] [PATCH] cryo: Improve socket support: add UDP and IPv6

[Benjamin Thery]

Today, I played a bit with inet sockets and cryo. With few modifications
I managed to "checkpoint-restart" programs that use UDP sockets to listen
and send data.

This patch improves socket checkpointing in cryo:
* Save/restore socket family: we can checkpoint IPv6 sockets now.
* Save/restore socket type: we can checkpoint UDP sockets too.

Simple test programs for UDP sockets available upon request :)

Regards,
Benjamin

Signed-off-by: Benjamin Thery <benjamin.thery at bull.net>
---
 cr.c |   63 ++++++++++++++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 50 insertions(+), 13 deletions(-)

Index: cryodev/cr.c
===================================================================
--- cryodev.orig/cr.c
+++ cryodev/cr.c
@@ -67,11 +67,15 @@ int pagesize = 0;
 
 typedef struct isockinfo_t {
 	int fdnum;
-	int type;			/* socket type: UDP, TCP */
+	int type;			/* socket type: SOCK_STREAM, SOCK_DGRAM */
+	int family;			/* socket family: AF_INET, AF_INET6 */
 	int mode;			/* bind, listen, connect */
 	int opt;			/* various sockopt */
 	int backlog;			/* for listen(2) */
-	struct sockaddr_in locaddr;	/* for bind(2) */
+	union {
+		struct sockaddr_in  saddr4;
+		struct sockaddr_in6 saddr6;
+	} locaddr;			/* for bind(2) */
 	char tcpstate[TPI_LEN];
 } isockinfo_t;
 
@@ -179,7 +183,7 @@ int getmaps(pid_t pid, memseg_t **p)
 
 int getsockinfo(pid_t pid, pinfo_t *pi, int num)
 {
-	struct sockaddr name;
+	struct sockaddr_storage name;
 	int namelen = (int)sizeof(name), ret = 0;
 	int tpi_len = TPI_LEN;
 	int flag, flaglen;
@@ -188,9 +192,11 @@ int getsockinfo(pid_t pid, pinfo_t *pi, 
 	/* get socketname and see if it is an unix or an inet socket */
 	memset(&name, 0, sizeof(name));
 	PT_GETSOCKNAME(pid, num, &name, &namelen);
-	t_d(name.sa_family);
+	t_d(name.ss_family);
 
-	if (name.sa_family != (sa_family_t)AF_INET) return ret;
+	if (name.ss_family != (sa_family_t)AF_INET &&
+	    name.ss_family != (sa_family_t)AF_INET6)
+		return ret;
 		
 	if (! (pi->si = (isockinfo_t *)realloc(pi->si, sizeof(isockinfo_t) * (pi->ns+1)))) return -1;
 	psi = &pi->si[pi->ns];
@@ -198,11 +204,25 @@ int getsockinfo(pid_t pid, pinfo_t *pi, 
 
 	//pi->si[pi->ns].fdnum = num;
 	psi->fdnum = num;
+	psi->family = name.ss_family;
 
 	psi->mode = ISOCK_UNKNOWN;
-	memcpy((void *)&psi->locaddr, (void *)&name, sizeof(name));
-	if (psi->locaddr.sin_addr.s_addr != 0 || psi->locaddr.sin_port != 0) psi->mode |= ISOCK_BIND;
-	
+	memcpy((void *)&psi->locaddr, (void *)&name, namelen);
+
+	if ((psi->family == AF_INET &&
+	     (psi->locaddr.saddr4.sin_addr.s_addr != INADDR_ANY ||
+	      psi->locaddr.saddr4.sin_port != 0)) ||
+	    (psi->family == AF_INET6 &&
+	     (memcmp(&psi->locaddr.saddr6.sin6_addr, &in6addr_any, 16) != 0 ||
+	      psi->locaddr.saddr6.sin6_port != 0)))
+		psi->mode |= ISOCK_BIND;
+
+	flag = 0;
+	flaglen = (int)sizeof(flag);
+	PT_GETSOCKOPT(pid, num, SOL_SOCKET, SO_TYPE, &flag, &flaglen);
+	if (flag)
+		psi->type = flag;
+
 	flag = 0;
 	flaglen = (int)sizeof(flag);
 	PT_GETSOCKOPT(pid, num, SOL_SOCKET, SO_REUSEADDR, &flag, &flaglen);
@@ -866,6 +886,7 @@ int restore_sock(int fd, pid_t pid)
 	int sock;
 	size_t bufsz;
 	isockinfo_t *isockinfo = NULL;
+	int len;
 
 	for (;;) {
 		read_item(fd, item, sizeof(item), &buf, &bufsz);
@@ -873,20 +894,36 @@ int restore_sock(int fd, pid_t pid)
 		else ITEM_SET(isockinfo, isockinfo_t);
 		else break;	// unknown item
 
-		t_d(sock = PT_SOCKET(pid, AF_INET, SOCK_STREAM, 0));
+		t_d(sock = PT_SOCKET(pid, isockinfo->family, isockinfo->type, 0));
 		if (sock < 0) {
 			ERROR("PT_SOCKET(%d, %d, %d, %d) errno=%d: %s",
-				pid, AF_INET, SOCK_STREAM, 0, sock, strerror(-sock)); 
+			      pid, isockinfo->family, isockinfo->type, 0,
+			      sock, strerror(-sock));
 		}
 		t_d(PT_DUP2(pid, sock, isockinfo->fdnum));
 		if (sock != isockinfo->fdnum) t_d(PT_CLOSE(pid, sock));
 		
 		if (isockinfo->mode & ISOCK_BIND) {
+			struct sockaddr *sa;
 			struct sockaddr_in sin;
+			struct sockaddr_in6 sin6;
 
-			memcpy((void *)&sin, (void *)&isockinfo->locaddr, sizeof(sin));
-			if (isockinfo->mode & ISOCK_CONNECT) sin.sin_port = htons(0);
-			t_d(PT_BIND(pid, isockinfo->fdnum, &sin, sizeof(sin)));
+			if (isockinfo->family == AF_INET) {
+				len = sizeof(sin);
+				memcpy((void *)&sin,
+				       (void *)&isockinfo->locaddr.saddr4, len);
+				if (isockinfo->mode & ISOCK_CONNECT)
+					sin6.sin6_port = htons(0);
+				sa = (struct sockaddr *) &sin;
+			} else {
+				len = sizeof(sin6);
+				memcpy((void *)&sin6,
+				       (void *)&isockinfo->locaddr.saddr6, len);
+				if (isockinfo->mode & ISOCK_CONNECT)
+					sin.sin_port = htons(0);
+				sa = (struct sockaddr *) &sin6;
+			}
+			t_d(PT_BIND(pid, isockinfo->fdnum, sa, len));
 		}
 		if (isockinfo->mode & ISOCK_LISTEN) {
 			t_d(PT_LISTEN(pid, isockinfo->fdnum, 64));	//FIXME: get backlog from TPI_INFO

-- 
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