IPv6 support originally by itojun@ with standalone mode fixes by me.

Tested by several people in both inetd and standalone mode w/ IPv4 and IPv6.

3 files changed, 190 insertions, 97 deletions

diff --git a/usr.sbin/popa3d/popa3d.8 b/usr.sbin/popa3d/popa3d.8
index 61389528de9..9d8d59a6c3d 100644
--- a/usr.sbin/popa3d/popa3d.8
+++ b/usr.sbin/popa3d/popa3d.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: popa3d.8,v 1.11 2004/07/17 20:54:24 brad Exp $
+.\"	$OpenBSD: popa3d.8,v 1.12 2004/07/20 17:07:34 millert Exp $
 .\"
 .\" Copyright (c) 2001-2003 Camiel Dobbelaar (cd@sentia.nl)
 .\" All rights reserved.
@@ -32,7 +32,7 @@
 .Nd "Post Office Protocol (POP3) server"
 .Sh SYNOPSIS
 .Nm
-.Op Fl D | V
+.Op Fl 46DV
 .Sh DESCRIPTION
 .Nm
 is a POP3 server.
@@ -60,6 +60,14 @@ To send mail, the SMTP protocol is commonly used; see
 .Pp
 The options are as follows:
 .Bl -tag -width Ds
+.It Fl 4
+In standalone mode
+.Pq Fl D ,
+listen to IPv4 only.
+.It Fl 6
+In standalone mode
+.Pq Fl D ,
+listen to IPv6 only.
 .It Fl D
 With this option set,
 .Nm
@@ -77,7 +85,6 @@ also does quite a few checks to significantly reduce the impact of
 connection flood attacks.
 .It Fl V
 Show version information and exit.
-.Pp
 .El
 .Pp
 Alternatively,
diff --git a/usr.sbin/popa3d/standalone.c b/usr.sbin/popa3d/standalone.c
index 2d146dd5b84..0e9d6ba2d1e 100644
--- a/usr.sbin/popa3d/standalone.c
+++ b/usr.sbin/popa3d/standalone.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: standalone.c,v 1.7 2004/07/17 20:54:24 brad Exp $ */
+/* $OpenBSD: standalone.c,v 1.8 2004/07/20 17:07:34 millert Exp $ */
 
 /*
  * Standalone POP server: accepts connections, checks the anti-flood limits,
@@ -17,6 +17,8 @@
 #include <syslog.h>
 #include <time.h>
 #include <errno.h>
+#include <netdb.h>
+#include <poll.h>
 #include <sys/times.h>
 #include <sys/types.h>
 #include <sys/wait.h>
@@ -36,6 +38,7 @@ int deny_severity = SYSLOG_PRI_HI;
 extern int log_error(char *s);
 extern int do_pop_startup(void);
 extern int do_pop_session(void);
+extern int af;
 
 typedef volatile sig_atomic_t va_int;
 
@@ -46,8 +49,8 @@ typedef volatile sig_atomic_t va_int;
  * information about sessions that we could have allowed to proceed.
  */
 static struct {
-	struct in_addr addr;		/* Source IP address */
-	volatile int pid;		/* PID of the server, or 0 for none */
+	char addr[NI_MAXHOST];		/* Source IP address */
+	va_int pid;			/* PID of the server, or 0 for none */
 	clock_t start;			/* When the server was started */
 	clock_t log;			/* When we've last logged a failure */
 } sessions[MAX_SESSIONS];
@@ -55,6 +58,8 @@ static struct {
 static va_int child_blocked;		/* We use blocking to avoid races */
 static va_int child_pending;		/* Are any dead children waiting? */
 
+int handle(int);
+
 /*
  * SIGCHLD handler.
  */
@@ -110,33 +115,67 @@ int do_standalone(void)
 int main(void)
 #endif
 {
-	int true = 1;
-	int sock, new;
-	struct sockaddr_in addr;
-	socklen_t addrlen;
-	pid_t pid;
-	struct tms buf;
-	clock_t now, log;
-	int i, j, n;
+	int error, i, n, true = 1;
+	struct pollfd *pfds;
+	struct addrinfo hints, *res, *res0;
+	char sbuf[NI_MAXSERV];
 
 	if (do_pop_startup()) return 1;
 
-	if ((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
-		return log_error("socket");
+	snprintf(sbuf, sizeof(sbuf), "%u", DAEMON_PORT);
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_family = af;
+	hints.ai_flags = AI_PASSIVE;
+	error = getaddrinfo(NULL, sbuf, &hints, &res0);
+	if (error)
+		return log_error("getaddrinfo");
+
+	i = 0;
+	for (res = res0; res; res = res->ai_next)
+		i++;
+
+	pfds = calloc(i, sizeof(pfds[0]));
+	if (!pfds)
+		return log_error("malloc");
+
+	i = 0;
+	for (res = res0; res; res = res->ai_next) {
+		if ((pfds[i].fd = socket(res->ai_family, res->ai_socktype,
+		    res->ai_protocol)) < 0)
+			continue;
+		pfds[i].events = POLLIN;
+
+		if (setsockopt(pfds[i].fd, SOL_SOCKET, SO_REUSEADDR,
+		    (void *)&true, sizeof(true))) {
+			close(pfds[i].fd);
+			continue;
+		}
+
+#ifdef IPV6_V6ONLY
+		if (res->ai_family == AF_INET6)
+			(void)setsockopt(pfds[i].fd, IPPROTO_IPV6, IPV6_V6ONLY,
+			    (void *)&true, sizeof(true));
+#endif
+
+		if (bind(pfds[i].fd, res->ai_addr, res->ai_addrlen)) {
+			close(pfds[i].fd);
+			continue;
+		}
 
-	if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
-	    (void *)&true, sizeof(true)))
-		return log_error("setsockopt");
+		if (listen(pfds[i].fd, MAX_BACKLOG)) {
+			close(pfds[i].fd);
+			continue;
+		}
 
-	memset(&addr, 0, sizeof(addr));
-	addr.sin_family = AF_INET;
-	addr.sin_addr.s_addr = inet_addr(DAEMON_ADDR);
-	addr.sin_port = htons(DAEMON_PORT);
-	if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)))
-		return log_error("bind");
+		i++;
+	}
+	freeaddrinfo(res0);
 
-	if (listen(sock, MAX_BACKLOG))
-		return log_error("listen");
+	if (i == 0)
+		return log_error("socket");
+
+	n = i;
 
 	chdir("/");
 	setsid();
@@ -159,95 +198,130 @@ int main(void)
 	signal(SIGCHLD, handle_child);
 
 	memset((void *)sessions, 0, sizeof(sessions));
-	log = 0;
-
-	new = 0;
 
 	while (1) {
 		child_blocked = 0;
 		if (child_pending) raise(SIGCHLD);
 
-		if (new > 0)
-		if (close(new)) return log_error("close");
+		i = poll(pfds, n, INFTIM);
+		if (i < 0) {
+			if (errno == EINTR || errno == EAGAIN)
+				continue;
+			return log_error("poll");
+		}
 
-		addrlen = sizeof(addr);
-		new = accept(sock, (struct sockaddr *)&addr, &addrlen);
+		for (i = 0; i < n; i++)
+			if (pfds[i].revents & POLLIN)
+				handle(pfds[i].fd);
+	}
+}
 
+int
+handle(int sock)
+{
+	clock_t now, log;
+	int new;
+	char hbuf[NI_MAXHOST];
+	struct sockaddr_storage addr;
+	int addrlen;
+	pid_t pid;
+	struct tms buf;
+	int error;
+	int j, n, i;
+
+	log = 0;
+	new = 0;
+
+	addrlen = sizeof(addr);
+	new = accept(sock, (struct sockaddr *)&addr, &addrlen);
 /*
  * I wish there was a portable way to classify errno's... In this case,
  * it appears to be better to risk eating up the CPU on a fatal error
  * rather than risk terminating the entire service because of a minor
  * temporary error having to do with one particular connection attempt.
  */
-		if (new < 0) continue;
-
-		now = times(&buf);
-		if (!now) now = 1;
-
-		child_blocked = 1;
-
-		j = -1; n = 0;
-		for (i = 0; i < MAX_SESSIONS; i++) {
-			if (sessions[i].start > now)
-				sessions[i].start = 0;
-			if (sessions[i].pid ||
-			    (sessions[i].start &&
-			    now - sessions[i].start < MIN_DELAY * CLK_TCK)) {
-				if (sessions[i].addr.s_addr ==
-				    addr.sin_addr.s_addr)
-				if (++n >= MAX_SESSIONS_PER_SOURCE) break;
-			} else
-			if (j < 0) j = i;
-		}
+	if (new < 0)
+		return -1;
+
+	error = getnameinfo((struct sockaddr *)&addr, addrlen,
+	    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST);
+	if (error) {
+		syslog(SYSLOG_PRI_HI,
+		    "%s: invalid IP address", hbuf);
+		return -1;
+	}
 
-		if (n >= MAX_SESSIONS_PER_SOURCE) {
-			if (!sessions[i].log ||
-			    now < sessions[i].log ||
-			    now - sessions[i].log >= MIN_DELAY * CLK_TCK) {
-				syslog(SYSLOG_PRI_HI,
-					"%s: per source limit reached",
-					inet_ntoa(addr.sin_addr));
-				sessions[i].log = now;
-			}
-			continue;
+	now = times(&buf);
+	if (!now)
+		now = 1;
+
+	child_blocked = 1;
+
+	j = -1;
+	n = 0;
+	for (i = 0; i < MAX_SESSIONS; i++) {
+		if (sessions[i].start > now)
+			sessions[i].start = 0;
+		if (sessions[i].pid ||
+		    (sessions[i].start &&
+		    now - sessions[i].start < MIN_DELAY * CLK_TCK)) {
+			if (strcmp(sessions[i].addr, hbuf) == 0)
+				if (++n >= MAX_SESSIONS_PER_SOURCE)
+					break;
+		} else if (j < 0)
+			j = i;
+	}
+
+	if (n >= MAX_SESSIONS_PER_SOURCE) {
+		if (!sessions[i].log ||
+		    now < sessions[i].log ||
+		    now - sessions[i].log >= MIN_DELAY * CLK_TCK) {
+			syslog(SYSLOG_PRI_HI,
+				"%s: per source limit reached",
+				hbuf);
+			sessions[i].log = now;
 		}
+		close(new);
+		return -1;
+	}
 
-		if (j < 0) {
-			if (!log ||
-			    now < log || now - log >= MIN_DELAY * CLK_TCK) {
-				syslog(SYSLOG_PRI_HI,
-					"%s: sessions limit reached",
-					inet_ntoa(addr.sin_addr));
-				log = now;
-			}
-			continue;
+	if (j < 0) {
+		if (!log ||
+		    now < log || now - log >= MIN_DELAY * CLK_TCK) {
+			syslog(SYSLOG_PRI_HI,
+			    "%s: sessions limit reached", hbuf);
+			log = now;
 		}
+		close(new);
+		return -1;
+	}
 
-		switch ((pid = fork())) {
-		case -1:
-			syslog(SYSLOG_PRI_ERROR, "%s: fork: %m",
-				inet_ntoa(addr.sin_addr));
-			break;
+	switch ((pid = fork())) {
+	case -1:
+		syslog(SYSLOG_PRI_ERROR, "%s: fork: %m", hbuf);
+		break;
 
-		case 0:
-			if (close(sock)) return log_error("close");
+	case 0:
 #if DAEMON_LIBWRAP
-			check_access(new);
+		check_access(new);
 #endif
-			syslog(SYSLOG_PRI_LO, "Session from %s",
-				inet_ntoa(addr.sin_addr));
-			if (dup2(new, 0) < 0) return log_error("dup2");
-			if (dup2(new, 1) < 0) return log_error("dup2");
-			if (dup2(new, 2) < 0) return log_error("dup2");
-			if (close(new)) return log_error("close");
-			return do_pop_session();
-
-		default:
-			sessions[j].addr = addr.sin_addr;
-			sessions[j].pid = pid;
-			sessions[j].start = now;
-			sessions[j].log = 0;
+		syslog(SYSLOG_PRI_LO, "Session from %s",
+			hbuf);
+		if (dup2(new, 0) < 0 || dup2(new, 1) < 0 || dup2(new, 2) < 0) {
+			log_error("dup2");
+			_exit(1);
 		}
+		closefrom(3);
+		_exit(do_pop_session());
+
+	default:
+		close(new);
+		strlcpy(sessions[j].addr, hbuf,
+			sizeof(sessions[j].addr));
+		sessions[j].pid = (va_int)pid;
+		sessions[j].start = now;
+		sessions[j].log = 0;
+		return 0;
 	}
 }
 
diff --git a/usr.sbin/popa3d/startup.c b/usr.sbin/popa3d/startup.c
index fc25a777b3b..88e9b9ade5e 100644
--- a/usr.sbin/popa3d/startup.c
+++ b/usr.sbin/popa3d/startup.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: startup.c,v 1.5 2004/07/17 20:54:24 brad Exp $ */
+/* $OpenBSD: startup.c,v 1.6 2004/07/20 17:07:34 millert Exp $ */
 
 /*
  * Command line option parsing.
@@ -8,6 +8,8 @@
 
 #if POP_OPTIONS
 
+#include <sys/types.h>
+#include <sys/socket.h>
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -30,9 +32,11 @@ extern char *__progname;
 static char *progname;
 #endif
 
+int af = PF_UNSPEC;
+
 static void usage(void)
 {
-	fprintf(stderr, "Usage: %s [-D] [-V]\n", progname);
+	fprintf(stderr, "Usage: %s [-46DV]\n", progname);
 	exit(1);
 }
 
@@ -52,8 +56,16 @@ int main(int argc, char **argv)
 		progname = POP_SERVER;
 #endif
 
-	while ((c = getopt(argc, argv, "DV")) != -1) {
+	while ((c = getopt(argc, argv, "46DV")) != -1) {
 		switch (c) {
+		case '4':
+			af = AF_INET;
+			break;
+
+		case '6':
+			af = AF_INET6;
+			break;
+
 		case 'D':
 			standalone++;
 			break;