added GetMask, lock and unlock

diff --git a/pppd/sys-bsd.c b/pppd/sys-bsd.c
index 505926f0ebef4deb9e66f4323caa82703dfe7b6a..c884a62914a94cff32294191f4739003a2ca087c 100644 (file)
--- a/pppd/sys-bsd.c
+++ b/pppd/sys-bsd.c
@@ -19,21 +19,25 @@
  */
 
 #ifndef lint
-static char rcsid[] = "$Id: sys-bsd.c,v 1.16 1995/04/24 05:37:51 paulus Exp $";
+static char rcsid[] = "$Id: sys-bsd.c,v 1.17 1995/04/27 00:33:39 paulus Exp $";
 #endif
 
 /*
  * TODO:
  */
 
+#include <stdio.h>
 #include <syslog.h>
 #include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <termios.h>
 #include <sys/ioctl.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/time.h>
-#include <sys/errno.h>
+#include <sys/stat.h>
 
 #include <net/if.h>
 #include <net/ppp_defs.h>
@@ -54,6 +58,8 @@ static int rtm_seq;
 static int     restore_term;   /* 1 => we've munged the terminal */
 static struct termios inittermios; /* Initial TTY termios */
 
+static char *lock_file;                /* name of lock file created */
+
 int sockfd;                    /* socket for doing interface ioctls */
 
 /*
@@ -938,7 +944,7 @@ get_ether_addr(ipaddr, hwaddr)
             */
            if (ioctl(sockfd, SIOCGIFNETMASK, &ifreq) < 0)
                continue;
-           mask = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
+           mask = ((struct sockaddr_in *) &ifreq.ifr_addr)->sin_addr.s_addr;
            if ((ipaddr & mask) != (ina & mask))
                continue;
 
@@ -970,3 +976,144 @@ get_ether_addr(ipaddr, hwaddr)
 
     return 0;
 }
+
+/*
+ * 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;
+}
+
+/*
+ * lock - create a lock file for the named lock device
+ */
+#define        LOCK_PREFIX     "/var/spool/lock/LCK.."
+
+int
+lock(dev)
+    char *dev;
+{
+    char hdb_lock_buffer[12];
+    int fd, pid, n;
+    char *p;
+
+    if ((p = strrchr(dev, '/')) != NULL)
+       dev = p + 1;
+    lock_file = malloc(strlen(LOCK_PREFIX) + strlen(dev) + 1);
+    if (lock_file == NULL)
+       novm("lock file name");
+    strcat(strcpy(lock_file, LOCK_PREFIX), dev);
+
+    while ((fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644)) < 0) {
+       if (errno == EEXIST
+           && (fd = open(lock_file, O_RDONLY, 0)) >= 0) {
+           /* Read the lock file to find out who has the device locked */
+           n = read(fd, hdb_lock_buffer, 11);
+           if (n > 0) {
+               hdb_lock_buffer[n] = 0;
+               pid = atoi(hdb_lock_buffer);
+           }
+           if (n <= 0) {
+               syslog(LOG_ERR, "Can't read pid from lock file %s", lock_file);
+               close(fd);
+           } else {
+               if (kill(pid, 0) == -1 && errno == ESRCH) {
+                   /* pid no longer exists - remove the lock file */
+                   if (unlink(lock_file) == 0) {
+                       close(fd);
+                       syslog(LOG_NOTICE, "Removed stale lock on %s (pid %d)",
+                              dev, pid);
+                       continue;
+                   } else
+                       syslog(LOG_WARNING, "Couldn't remove stale lock on %s",
+                              dev);
+               } else
+                   syslog(LOG_NOTICE, "Device %s is locked by pid %d",
+                          dev, pid);
+           }
+           close(fd);
+       } else
+           syslog(LOG_ERR, "Can't create lock file %s: %m", lock_file);
+       free(lock_file);
+       lock_file = NULL;
+       return -1;
+    }
+
+    sprintf(hdb_lock_buffer, "%10d\n", getpid());
+    write(fd, hdb_lock_buffer, 11);
+
+    close(fd);
+    return 0;
+}
+
+/*
+ * unlock - remove our lockfile
+ */
+unlock()
+{
+    if (lock_file) {
+       unlink(lock_file);
+       free(lock_file);
+       lock_file = NULL;
+    }
+}