IPv6 support for lpr.

Reviewed by:	freebsd-current (no objection)
Obtained from:	KAME

usr.sbin/lpr/Makefile.inc

@@ -1,5 +1,6 @@
 # $FreeBSD$
 
+CFLAGS+=-DINET6
 CWARNFLAGS=	-Wall -Wnested-externs -Wmissing-prototypes -Wno-unused -Wredundant-decls -Wstrict-prototypes
 
 .if exists(${.OBJDIR}/../common_source)

usr.sbin/lpr/common_source/lp.h

@@ -36,6 +36,7 @@
 
 #include <sys/queue.h>
 #include <time.h>
+#include <netdb.h>
 
 /*
  * All this information used to be in global static variables shared
@@ -156,14 +157,14 @@ extern char	*name;		/* program name */
 				/* host machine name */
 extern char	host[MAXHOSTNAMELEN];
 extern char	*from;		/* client's machine name */
-#define MAXIPSTRLEN 32		/* maxlen of an IP-address as a string */
+extern char	from_ip[NI_MAXHOST];   /* client machine's IP address */
-extern char	from_ip[MAXIPSTRLEN];   /* client machine's IP address */
 
 extern int	requ[];		/* job number of spool entries */
 extern int	requests;	/* # of spool requests */
 extern char	*user[];        /* users to process */
 extern int	users;		/* # of users in user array */
 extern char	*person;	/* name of person doing lprm */
+extern u_char	family;		/* address family */
 
 /*
  * Structure used for building a sorted list of control files.

usr.sbin/lpr/common_source/net.c

@@ -67,7 +67,13 @@ static const char rcsid[] =
 
 char	 host[MAXHOSTNAMELEN];	/* host machine name */
 char	*from = host;		/* client's machine name */
-char	 from_ip[MAXIPSTRLEN] = ""; /* client machine's IP address */
+char	 from_ip[NI_MAXHOST] = ""; /* client machine's IP address */
+
+#ifdef INET6
+u_char	family = PF_UNSPEC;
+#else
+u_char	family = PF_INET;
+#endif
 
 extern uid_t	uid, euid;
 
@@ -79,46 +85,52 @@ extern uid_t	uid, euid;
 int
 getport(const struct printer *pp, const char *rhost, int rport)
 {
-	struct hostent *hp;
+	struct addrinfo hints, *res, *ai;
-	struct servent *sp;
-	struct sockaddr_in sin;
 	int s, timo = 1, lport = IPPORT_RESERVED - 1;
-	int err;
+	int err, refused = 0;
 
 	/*
 	 * Get the host address and port number to connect to.
 	 */
 	if (rhost == NULL)
 		fatal(pp, "no remote host to connect to");
-	bzero((char *)&sin, sizeof(sin));
+	memset(&hints, 0, sizeof(hints));
-	sin.sin_len = sizeof sin;
+	hints.ai_family = family;
-	sin.sin_family = AF_INET;
+	hints.ai_socktype = SOCK_STREAM;
-	if (inet_aton(rhost, &sin.sin_addr) == 0) {
+	hints.ai_protocol = 0;
-		hp = gethostbyname2(rhost, AF_INET);
+	err = getaddrinfo(rhost, (rport == 0 ? "printer" : NULL),
-		if (hp == NULL)
+			  &hints, &res);
-			fatal(pp, "cannot resolve %s: %s", rhost, 
+	if (err)
-			      hstrerror(h_errno));
+		fatal(pp, "%s\n", gai_strerror(err));
-		/* XXX - should deal with more addresses */
+	if (rport != 0)
-		sin.sin_addr = *(struct in_addr *)hp->h_addr_list[0];
+		((struct sockaddr_in *) res->ai_addr)->sin_port = htons(rport);
-	}
-	if (rport == 0) {
-		sp = getservbyname("printer", "tcp");
-		if (sp == NULL)
-			fatal(pp, "printer/tcp: unknown service");
-		sin.sin_port = sp->s_port;
-	} else
-		sin.sin_port = htons(rport);
 
 	/*
 	 * Try connecting to the server.
 	 */
+	ai = res;
 retry:
 	seteuid(euid);
-	s = rresvport(&lport);
+	s = rresvport_af(&lport, ai->ai_family);
 	seteuid(uid);
-	if (s < 0)
+	if (s < 0) {
+		if (errno != EAGAIN) {
+			if (ai->ai_next) {
+				ai = ai->ai_next;
+				goto retry;
+			}
+			if (refused && timo <= 16) {
+				sleep(timo);
+				timo *= 2;
+				refused = 0;
+				ai = res;
+				goto retry;
+			}
+		}
+		freeaddrinfo(res);
 		return(-1);
-	if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
+	}
+	if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0) {
 		err = errno;
 		(void) close(s);
 		errno = err;
@@ -128,16 +140,28 @@ getport(const struct printer *pp, const char *rhost, int rport)
 		 * rresvport should guarantee that the chosen port will
 		 * never result in an EADDRINUSE).
 		 */
-		if (errno == EADDRINUSE)
+		if (errno == EADDRINUSE) {
-			goto retry;
-
-		if (errno == ECONNREFUSED && timo <= 16) {
-			sleep(timo);
-			timo *= 2;
 			goto retry;
 		}
+
+		if (errno == ECONNREFUSED)
+			refused++;
+
+		if (ai->ai_next != NULL) {
+			ai = ai->ai_next;
+			goto retry;
+		}
+		if (refused && timo <= 16) {
+			sleep(timo);
+			timo *= 2;
+			refused = 0;
+			ai = res;
+			goto retry;
+		}
+		freeaddrinfo(res);
 		return(-1);
 	}
+	freeaddrinfo(res);
 	return(s);
 }
 
@@ -155,10 +179,10 @@ char *
 checkremote(struct printer *pp)
 {
 	char name[MAXHOSTNAMELEN];
-	register struct hostent *hp;
+	struct addrinfo hints, *local_res, *remote_res, *lr, *rr;
 	char *err;
-	struct in_addr *localaddrs;
+	int ncommonaddrs, error;
-	int i, j, nlocaladdrs, ncommonaddrs;
+	char h1[NI_MAXHOST], h2[NI_MAXHOST];
 
 	if (!pp->rp_matches_local) { /* Remote printer doesn't match local */
 		pp->remote = 1;
@@ -166,57 +190,63 @@ checkremote(struct printer *pp)
 	}
 
 	pp->remote = 0;	/* assume printer is local */
-	if (pp->remote_host != NULL) {
+	if (pp->remote_host == NULL)
-		/* get the addresses of the local host */
+		return NULL;
-		gethostname(name, sizeof(name));
-		name[sizeof(name) - 1] = '\0';
-		hp = gethostbyname2(name, AF_INET);
-		if (hp == (struct hostent *) NULL) {
-			asprintf(&err, "unable to get official name "
-				 "for local machine %s: %s",
-				 name, hstrerror(h_errno));
-			return err;
-		}
-		for (i = 0; hp->h_addr_list[i]; i++)
-			;
-		nlocaladdrs = i;
-		localaddrs = malloc(i * sizeof(struct in_addr));
-		if (localaddrs == 0) {
-			asprintf(&err, "malloc %lu bytes failed",
-				 (u_long)i * sizeof(struct in_addr));
-			return err;
-		}
-		for (i = 0; hp->h_addr_list[i]; i++)
-			localaddrs[i] = *(struct in_addr *)hp->h_addr_list[i];
 
-		/* get the official name of RM */
+	/* get the addresses of the local host */
-		hp = gethostbyname2(pp->remote_host, AF_INET);
+	gethostname(name, sizeof(name));
-		if (hp == (struct hostent *) NULL) {
+	name[sizeof(name) - 1] = '\0';
-			asprintf(&err, "unable to get address list for "
-				 "remote machine %s: %s",
-				 pp->remote_host, hstrerror(h_errno));
-			free(localaddrs);
-			return err;
-		}
 
-		ncommonaddrs = 0;
+	memset(&hints, 0, sizeof(hints));
-		for (i = 0; i < nlocaladdrs; i++) {
+	hints.ai_family = family;
-			for (j = 0; hp->h_addr_list[j]; j++) {
+	hints.ai_socktype = SOCK_STREAM;
-				char *them = hp->h_addr_list[j];
+	hints.ai_flags = AI_PASSIVE;
-				if (localaddrs[i].s_addr ==
+	if ((error = getaddrinfo(name, NULL, &hints, &local_res)) != 0) {
-				    (*(struct in_addr *)them).s_addr)
+		asprintf(&err, "unable to get official name "
-					ncommonaddrs++;
+			 "for local machine %s: %s",
-			}
+			 name, gai_strerror(error));
-		}
+		return err;
-			
-		/*
-		 * if the two hosts do not share at least one IP address
-		 * then the printer must be remote.
-		 */
-		if (ncommonaddrs == 0)
-			pp->remote = 1;
-		free(localaddrs);
 	}
+
+	/* get the official name of RM */
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = family;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_PASSIVE;
+	if ((error = getaddrinfo(pp->remote_host, NULL,
+				 &hints, &remote_res)) != 0) {
+		asprintf(&err, "unable to get address list for "
+			 "remote machine %s: %s",
+			 pp->remote_host, gai_strerror(error));
+		freeaddrinfo(local_res);
+		return err;
+	}
+
+	ncommonaddrs = 0;
+	for (lr = local_res; lr; lr = lr->ai_next) {
+		h1[0] = '\0';
+		if (getnameinfo(lr->ai_addr, lr->ai_addrlen, h1, sizeof(h1),
+				NULL, 0, NI_NUMERICHOST | NI_WITHSCOPEID) != 0)
+			continue;
+		for (rr = remote_res; rr; rr = rr->ai_next) {
+			h2[0] = '\0';
+			if (getnameinfo(rr->ai_addr, rr->ai_addrlen,
+					h2, sizeof(h2), NULL, 0,
+					NI_NUMERICHOST | NI_WITHSCOPEID) != 0)
+				continue;
+			if (strcmp(h1, h2) == 0)
+				ncommonaddrs++;
+		}
+	}
+			
+	/*
+	 * if the two hosts do not share at least one IP address
+	 * then the printer must be remote.
+	 */
+	if (ncommonaddrs == 0)
+		pp->remote = 1;
+	freeaddrinfo(local_res);
+	freeaddrinfo(remote_res);
 	return NULL;
 }
 

usr.sbin/lpr/lpd/lpd.8

@@ -40,7 +40,7 @@
 .Nd line printer spooler daemon
 .Sh SYNOPSIS
 .Nm
-.Op Fl dlp
+.Op Fl dlp46
 .Op Ar port#
 .Sh DESCRIPTION
 .Nm Lpd
@@ -81,6 +81,12 @@ The
 flag causes
 .Nm
 not to open an Internet listening socket.
+.It Fl 4
+Inet only.
+.It Fl 6
+Inet6 only.
+.It Fl 46
+Inet and inet6 (default).
 .It Ar "port#"
 The Internet port number used to rendezvous
 with other processes is normally obtained with

usr.sbin/lpr/lpd/lpd.c

@@ -112,12 +112,14 @@ static void       reapchild __P((int));
 static void       mcleanup __P((int));
 static void       doit __P((void));
 static void       startup __P((void));
-static void       chkhost __P((struct sockaddr_in *));
+static void       chkhost __P((struct sockaddr *));
 static int	  ckqueue __P((struct printer *));
 static void	  usage __P((void));
-/* From rcmd.c: */
+static int	  *socksetup __P((int, int));
-int		  __ivaliduser __P((FILE *, u_long, const char *, 
+
-				    const char *));
+/* XXX from libc/net/rcmd.c */
+extern int __ivaliduser_sa __P((FILE *, struct sockaddr *, socklen_t,
+				const char *, const char *));
 
 uid_t	uid, euid;
 
@@ -126,13 +128,14 @@ main(argc, argv)
 	int argc;
 	char **argv;
 {
-	int errs, f, funix, finet, fromlen, i, socket_debug;
+	int errs, f, funix, *finet, fromlen, i, options, socket_debug;
 	fd_set defreadfds;
 	struct sockaddr_un un, fromunix;
-	struct sockaddr_in sin, frominet;
+	struct sockaddr_storage frominet;
 	int lfd;
 	sigset_t omask, nmask;
 	struct servent *sp, serv;
+	int inet_flag = 0, inet6_flag = 0;
 
 	euid = geteuid();	/* these shouldn't be different */
 	uid = getuid();
@@ -145,7 +148,7 @@ main(argc, argv)
 		errx(EX_NOPERM,"must run as root");
 
 	errs = 0;
-	while ((i = getopt(argc, argv, "dlp")) != -1)
+	while ((i = getopt(argc, argv, "dlp46")) != -1)
 		switch (i) {
 		case 'd':
 			socket_debug++;
@@ -156,9 +159,19 @@ main(argc, argv)
 		case 'p':
 			pflag++;
 			break;
+		case '4':
+			family = PF_INET;
+			inet_flag++;
+			break;
+		case '6':
+			family = PF_INET6;
+			inet6_flag++;
+			break;
 		default:
 			errs++;
 		}
+	if (inet_flag && inet6_flag)
+		family = PF_UNSPEC;
 	argc -= optind;
 	argv += optind;
 	if (errs)
@@ -283,32 +296,17 @@ main(argc, argv)
 	FD_ZERO(&defreadfds);
 	FD_SET(funix, &defreadfds);
 	listen(funix, 5);
-	finet = -1;
 	if (pflag == 0) {
-		finet = socket(AF_INET, SOCK_STREAM, 0);
+		options = SO_REUSEADDR;
-		if (finet >= 0) {
+		if (socket_debug)
-			i = 1;
+			options |= SO_DEBUG;
-			if (setsockopt(finet, SOL_SOCKET, SO_REUSEADDR, &i,
+		finet = socksetup(family, options);
-			    sizeof i) < 0) {
+	} else
-				syslog(LOG_ERR, "setsockopt(SO_REUSEADDR): %m");
+		finet = NULL;	/* pretend we couldn't open TCP socket. */
-				mcleanup(0);
+	if (finet) {
-			}
+		for (i = 1; i <= *finet; i++) {
-			if (socket_debug &&
+			FD_SET(finet[i], &defreadfds);
-			    setsockopt(finet, SOL_SOCKET, SO_DEBUG,
+			listen(finet[i], 5);
-				&socket_debug, sizeof(socket_debug)) < 0) {
-				syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
-				mcleanup(0);
-			}
-			memset(&sin, 0, sizeof(sin));
-			sin.sin_family = AF_INET;
-			sin.sin_port = sp->s_port;
-			if (bind(finet, (struct sockaddr *)&sin,
-			    sizeof(sin)) < 0) {
-				syslog(LOG_ERR, "bind: %m");
-				mcleanup(0);
-			}
-			FD_SET(finet, &defreadfds);
-			listen(finet, 5);
 		}
 	}
 	/*
@@ -322,7 +320,7 @@ main(argc, argv)
 	 * XXX - should be redone for multi-protocol
 	 */
 	for (;;) {
-		int domain, nfds, s;
+		int domain = -1, nfds, s = -1;
 		fd_set readfds;
 
 		FD_COPY(&defreadfds, &readfds);
@@ -338,14 +336,15 @@ main(argc, argv)
 			domain = AF_UNIX, fromlen = sizeof(fromunix);
 			s = accept(funix,
 			    (struct sockaddr *)&fromunix, &fromlen);
-		} else if (pflag == 0) /* if (FD_ISSET(finet, &readfds)) */  {
+ 		} else {
-			domain = AF_INET, fromlen = sizeof(frominet);
+                        for (i = 1; i <= *finet; i++) 
-			s = accept(finet,
+				if (FD_ISSET(finet[i], &readfds)) {
-			    (struct sockaddr *)&frominet, &fromlen);
+					domain = AF_INET;
-			if (frominet.sin_port == htons(20)) {
+					fromlen = sizeof(frominet);
-				close(s);
+					s = accept(finet[i],
-				continue;
+					    (struct sockaddr *)&frominet,
-			}
+					    &fromlen);
+				}
 		}
 		if (s < 0) {
 			if (errno != EINTR)
@@ -359,14 +358,16 @@ main(argc, argv)
 			signal(SIGQUIT, SIG_IGN);
 			signal(SIGTERM, SIG_IGN);
 			(void) close(funix);
-			if (pflag == 0) {
+			if (pflag == 0 && finet) {
-				(void) close(finet);
+                        	for (i = 1; i <= *finet; i++) 
+					(void)close(finet[i]);
 			}
 			dup2(s, 1);
 			(void) close(s);
 			if (domain == AF_INET) {
+				/* for both AF_INET and AF_INET6 */
 				from_remote = 1;
-				chkhost(&frominet);
+ 				chkhost((struct sockaddr *)&frominet);
 			} else
 				from_remote = 0;
 			doit();
@@ -606,35 +607,75 @@ ckqueue(pp)
  */
 static void
 chkhost(f)
-	struct sockaddr_in *f;
+	struct sockaddr *f;
 {
-	register struct hostent *hp;
+	struct addrinfo hints, *res, *r;
 	register FILE *hostf;
 	int first = 1;
 	int good = 0;
+	char host[NI_MAXHOST], ip[NI_MAXHOST];
+	char serv[NI_MAXSERV];
+	int error, addrlen;
+	caddr_t addr;
+
+	error = getnameinfo(f, f->sa_len, NULL, 0, serv, sizeof(serv),
+			    NI_NUMERICSERV);
+	if (error || atoi(serv) >= IPPORT_RESERVED)
+		fatal(0, "Malformed from address");
 
 	/* Need real hostname for temporary filenames */
-	hp = gethostbyaddr((char *)&f->sin_addr,
+	error = getnameinfo(f, f->sa_len, host, sizeof(host), NULL, 0,
-	    sizeof(struct in_addr), f->sin_family);
+			    NI_NAMEREQD);
-	if (hp == NULL)
+	if (error) {
-		fatal(0, "Host name for your address (%s) unknown",
+		error = getnameinfo(f, f->sa_len, host, sizeof(host), NULL, 0,
-			inet_ntoa(f->sin_addr));
+				    NI_NUMERICHOST | NI_WITHSCOPEID);
+		if (error)
+			fatal(0, "Host name for your address unknown");
+		else
+			fatal(0, "Host name for your address (%s) unknown",
+			      host);
+	}
 
-	(void) strncpy(fromb, hp->h_name, sizeof(fromb) - 1);
+	(void)strncpy(fromb, host, sizeof(fromb) - 1);
 	fromb[sizeof(fromb) - 1] = '\0';
 	from = fromb;
-	strncpy(from_ip, inet_ntoa(f->sin_addr), MAXIPSTRLEN);
+
+	/* Need address in stringform for comparison (no DNS lookup here) */
+	error = getnameinfo(f, f->sa_len, host, sizeof(host), NULL, 0,
+			    NI_NUMERICHOST | NI_WITHSCOPEID);
+	if (error)
+		fatal(0, "Cannot print address");
+	strncpy(from_ip, host, NI_MAXHOST);
 	from_ip[sizeof(from_ip) - 1] = '\0';
 
+	/* Reject numeric addresses */
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = family;
+	hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
+	hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST;
+	if (getaddrinfo(fromb, NULL, &hints, &res) == 0) {
+		freeaddrinfo(res);
+		fatal(0, "reverse lookup results in non-FQDN %s", fromb);
+	}
+
 	/* Check for spoof, ala rlogind */
-	hp = gethostbyname(fromb);
+	memset(&hints, 0, sizeof(hints));
-	if (!hp)
+	hints.ai_family = family;
-		fatal(0, "hostname for your address (%s) unknown", from_ip);
+	hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
-	for (; good == 0 && hp->h_addr_list[0] != NULL; hp->h_addr_list++) {
+	error = getaddrinfo(fromb, NULL, &hints, &res);
-		if (!bcmp(hp->h_addr_list[0], (caddr_t)&f->sin_addr,
+	if (error) {
-		    sizeof(f->sin_addr)))
+		fatal(0, "hostname for your address (%s) unknown: %s", from_ip,
+		      gai_strerror(error));
+	}
+	good = 0;
+	for (r = res; good == 0 && r; r = r->ai_next) {
+		error = getnameinfo(r->ai_addr, r->ai_addrlen, ip, sizeof(ip),
+				    NULL, 0, NI_NUMERICHOST | NI_WITHSCOPEID);
+		if (!error && !strcmp(from_ip, ip))
 			good = 1;
 	}
+	if (res)
+		freeaddrinfo(res);
 	if (good == 0)
 		fatal(0, "address for your hostname (%s) not matched",
 		    from_ip);
@@ -642,8 +683,7 @@ chkhost(f)
 	hostf = fopen(_PATH_HOSTSEQUIV, "r");
 again:
 	if (hostf) {
-		if (__ivaliduser(hostf, f->sin_addr.s_addr,
+		if (__ivaliduser_sa(hostf, f, f->sa_len, DUMMY, DUMMY) == 0) {
-		    DUMMY, DUMMY) == 0) {
 			(void) fclose(hostf);
 			return;
 		}
@@ -664,3 +704,86 @@ usage()
 	fprintf(stderr, "usage: lpd [-dlp] [port#]\n");
 	exit(EX_USAGE);
 }
+
+/* setup server socket for specified address family */
+/* if af is PF_UNSPEC more than one socket may be returned */
+/* the returned list is dynamically allocated, so caller needs to free it */
+static int *
+socksetup(af, options)
+        int af, options;
+{
+	struct addrinfo hints, *res, *r;
+	int error, maxs, *s, *socks;
+	const int on = 1;
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_flags = AI_PASSIVE;
+	hints.ai_family = af;
+	hints.ai_socktype = SOCK_STREAM;
+	error = getaddrinfo(NULL, "printer", &hints, &res);
+	if (error) {
+		syslog(LOG_ERR, "%s", gai_strerror(error));
+		mcleanup(0);
+	}
+
+	/* Count max number of sockets we may open */
+	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
+		;
+	socks = malloc((maxs + 1) * sizeof(int));
+	if (!socks) {
+		syslog(LOG_ERR, "couldn't allocate memory for sockets");
+		mcleanup(0);
+	}
+
+	*socks = 0;   /* num of sockets counter at start of array */
+	s = socks + 1;
+	for (r = res; r; r = r->ai_next) {
+		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
+		if (*s < 0) {
+			syslog(LOG_DEBUG, "socket(): %m");
+			continue;
+		}
+		if (options & SO_REUSEADDR)
+			if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR, &on,
+				       sizeof(on)) < 0) {
+				syslog(LOG_ERR, "setsockopt(SO_REUSEADDR): %m");
+				close(*s);
+				continue;
+			}
+		if (options & SO_DEBUG)
+			if (setsockopt(*s, SOL_SOCKET, SO_DEBUG,
+				       &on, sizeof(on)) < 0) {
+				syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
+				close(*s);
+				continue;
+			}
+#ifdef IPV6_BINDV6ONLY
+		if (r->ai_family == AF_INET6) {
+			if (setsockopt(*s, IPPROTO_IPV6, IPV6_BINDV6ONLY,
+				       &on, sizeof(on)) < 0) {
+				syslog(LOG_ERR,
+				       "setsockopt (IPV6_BINDV6ONLY): %m");
+				close(*s);
+				continue;
+			}
+		}
+#endif
+		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
+			syslog(LOG_DEBUG, "bind(): %m");
+			close(*s);
+			continue;
+		}
+		(*socks)++;
+		s++;
+	}
+
+	if (res)
+		freeaddrinfo(res);
+
+	if (*socks == 0) {
+		syslog(LOG_ERR, "Couldn't bind to any socket");
+		free(socks);
+		mcleanup(0);
+	}
+	return(socks);
+}