From 800ac338fdfc693ce08ede826907d7137c2c6f55 Mon Sep 17 00:00:00 2001
From: Paul Mackerras <paulus@samba.org>
Date: Thu, 27 Apr 1995 00:35:43 +0000
Subject: [PATCH] added GetMask

---
 pppd/sys-aix4.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++-
 pppd/sys-str.c  | 69 ++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/pppd/sys-aix4.c b/pppd/sys-aix4.c
index 897d24a..e96e520 100644
--- a/pppd/sys-aix4.c
+++ b/pppd/sys-aix4.c
@@ -19,7 +19,7 @@
  */
 
 #ifndef lint
-static char rcsid[] = "$Id: sys-aix4.c,v 1.3 1995/04/24 05:50:43 paulus Exp $";
+static char rcsid[] = "$Id: sys-aix4.c,v 1.4 1995/04/27 00:33:49 paulus Exp $";
 #endif
 
 /*
@@ -1106,6 +1106,73 @@ get_ether_addr(ipaddr, hwaddr)
     return(found);
 }
 
+/*
+ * Return user specified netmask, modified by any mask we might determine
+ * for address `addr' (in network byte order).
+ * Here we scan through the system's list of interfaces, looking for
+ * any non-point-to-point interfaces which might appear to be on the same
+ * network as `addr'.  If we find any, we OR in their netmask to the
+ * user-specified netmask.
+ */
+u_int32_t
+GetMask(addr)
+    u_int32_t addr;
+{
+    u_int32_t mask, nmask, ina;
+    struct ifreq *ifr, *ifend, ifreq;
+    struct ifconf ifc;
+    struct ifreq ifs[MAX_IFS];
+
+    addr = ntohl(addr);
+    if (IN_CLASSA(addr))	/* determine network mask for address class */
+	nmask = IN_CLASSA_NET;
+    else if (IN_CLASSB(addr))
+	nmask = IN_CLASSB_NET;
+    else
+	nmask = IN_CLASSC_NET;
+    /* class D nets are disallowed by bad_ip_adrs */
+    mask = netmask | htonl(nmask);
+
+    /*
+     * Scan through the system's network interfaces.
+     */
+    ifc.ifc_len = sizeof(ifs);
+    ifc.ifc_req = ifs;
+    if (ioctl(sockfd, SIOCGIFCONF, &ifc) < 0) {
+	syslog(LOG_WARNING, "ioctl(SIOCGIFCONF): %m");
+	return mask;
+    }
+    ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
+    for (ifr = ifc.ifc_req; ifr < ifend; ifr = (struct ifreq *)
+	 	((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len)) {
+	/*
+	 * Check the interface's internet address.
+	 */
+	if (ifr->ifr_addr.sa_family != AF_INET)
+	    continue;
+	ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
+	if ((ntohl(ina) & nmask) != (addr & nmask))
+	    continue;
+	/*
+	 * Check that the interface is up, and not point-to-point or loopback.
+	 */
+	strncpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
+	if (ioctl(sockfd, SIOCGIFFLAGS, &ifreq) < 0)
+	    continue;
+	if ((ifreq.ifr_flags & (IFF_UP|IFF_POINTOPOINT|IFF_LOOPBACK))
+	    != IFF_UP)
+	    continue;
+	/*
+	 * Get its netmask and OR it into our mask.
+	 */
+	if (ioctl(sockfd, SIOCGIFNETMASK, &ifreq) < 0)
+	    continue;
+	mask |= ((struct sockaddr_in *)&ifreq.ifr_addr)->sin_addr.s_addr;
+    }
+
+    return mask;
+}
+
 #define	WTMPFILE	"/var/adm/wtmp"
 
 int
diff --git a/pppd/sys-str.c b/pppd/sys-str.c
index 689bb87..051f10d 100644
--- a/pppd/sys-str.c
+++ b/pppd/sys-str.c
@@ -19,7 +19,7 @@
  */
 
 #ifndef lint
-static char rcsid[] = "$Id: sys-str.c,v 1.17 1995/04/24 05:36:14 paulus Exp $";
+static char rcsid[] = "$Id: sys-str.c,v 1.18 1995/04/27 00:35:43 paulus Exp $";
 #endif
 
 /*
@@ -1099,6 +1099,73 @@ logwtmp(line, name, host)
     close(fd);
 }
 
+/*
+ * Return user specified netmask, modified by any mask we might determine
+ * for address `addr' (in network byte order).
+ * Here we scan through the system's list of interfaces, looking for
+ * any non-point-to-point interfaces which might appear to be on the same
+ * network as `addr'.  If we find any, we OR in their netmask to the
+ * user-specified netmask.
+ */
+u_int32_t
+GetMask(addr)
+    u_int32_t addr;
+{
+    u_int32_t mask, nmask, ina;
+    struct ifreq *ifr, *ifend, ifreq;
+    struct ifconf ifc;
+    struct ifreq ifs[MAX_IFS];
+
+    addr = ntohl(addr);
+    if (IN_CLASSA(addr))	/* determine network mask for address class */
+	nmask = IN_CLASSA_NET;
+    else if (IN_CLASSB(addr))
+	nmask = IN_CLASSB_NET;
+    else
+	nmask = IN_CLASSC_NET;
+    /* class D nets are disallowed by bad_ip_adrs */
+    mask = netmask | htonl(nmask);
+
+    /*
+     * Scan through the system's network interfaces.
+     */
+    ifc.ifc_len = sizeof(ifs);
+    ifc.ifc_req = ifs;
+    if (ioctl(sockfd, SIOCGIFCONF, &ifc) < 0) {
+	syslog(LOG_WARNING, "ioctl(SIOCGIFCONF): %m");
+	return mask;
+    }
+    ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
+    for (ifr = ifc.ifc_req; ifr < ifend; ifr = (struct ifreq *)
+	 	((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len)) {
+	/*
+	 * Check the interface's internet address.
+	 */
+	if (ifr->ifr_addr.sa_family != AF_INET)
+	    continue;
+	ina = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
+	if ((ntohl(ina) & nmask) != (addr & nmask))
+	    continue;
+	/*
+	 * Check that the interface is up, and not point-to-point or loopback.
+	 */
+	strncpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifreq.ifr_name));
+	if (ioctl(sockfd, SIOCGIFFLAGS, &ifreq) < 0)
+	    continue;
+	if ((ifreq.ifr_flags & (IFF_UP|IFF_POINTOPOINT|IFF_LOOPBACK))
+	    != IFF_UP)
+	    continue;
+	/*
+	 * Get its netmask and OR it into our mask.
+	 */
+	if (ioctl(sockfd, SIOCGIFNETMASK, &ifreq) < 0)
+	    continue;
+	mask |= ((struct sockaddr_in *)&ifreq.ifr_addr)->sin_addr.s_addr;
+    }
+
+    return mask;
+}
+
 /*
  * Code for locking/unlocking the serial device.
  * This code is derived from chat.c.
-- 
2.39.2