--- adt.c	Thu Feb 15 02:20:45 2001
+++ adt-passive.c	Sun May 26 01:50:48 2002
@@ -171,9 +171,9 @@
 char *FindDesc = "Performing local case insensitive substring search";
 char GotComplete, GotLocal, GotRecent, FilesAreRemote;
 char Flat, Readme, Silent, Path[250], Action;
 char InitialSetup;
-char Connected;
+char Connected, Passive_FTP;
 char MaskSIGINT, GotSIGINT;
 
 int (*disp_init) ();
 int (*disp_cleanup) ();
@@ -2039,8 +2039,43 @@
 
   return (result >= 100) && (result < 400);
 }
 
+int bftp_getdataconnection_passive(struct sockaddr_in *sin, char *buf) {
+  int d, i, a[7];
+  char *p = buf;
+
+  /* send PASV command */
+  if (!bftp_io) return -1;
+  fflush(bftp_io); rewind(bftp_io);
+  fputs("PASV\r\n", bftp_io);
+  fflush(bftp_io); rewind(bftp_io);
+  if (!fgets(buf, BFTP_BUFSIZE, bftp_io)) return -1;
+
+  /* response should be "227 Entering Passive Mode (A,B,C,D,E,F)\r\n"
+   * where A-F are numbers from 0 to 255. The IP address to connect
+   * to for data is A.B.C.D, and the port is (E<<8 + F)
+   */
+  for (i = 0; i < 7; i++) {
+    d = 0;
+    while (*p && (*p < '0' || *p > '9')) p++;
+    while (*p && (*p >= '0' && *p <= '9')) d = ((d * 10) + (*p-'0')), p++;
+    if (d > 255) return -1;
+    a[i] = d;
+  }
+
+  if (!*p || (a[0] != 227)) return -1;
+
+  sin->sin_family = AF_INET;
+  sin->sin_addr.s_addr = htonl((a[1]<<24) | (a[2]<<16) | (a[3]<<8) | a[4]);
+  sin->sin_port = htons((a[5]<<8) | a[6]);
+
+  i = sizeof(struct sockaddr_in);
+  if ((d = socket(PF_INET, SOCK_STREAM, 0)) < 0) return -1;
+  if (connect(d, (struct sockaddr *) sin, i) < 0) { close(d); return -1; }
+  return d;
+}
+
 int bftp_getdataconnection()
 {
   struct sockaddr_in sin;
   struct hostent *hp;
@@ -2092,13 +2127,22 @@
 
   sprintf(buf, "Getting %s...", remote);
   progress(buf);
 
-  if ((s = bftp_getdataconnection()) >= 0) {
+  s = (Passive_FTP)
+    ? bftp_getdataconnection_passive(&sin, buf)
+    : bftp_getdataconnection();
+  if (s >= 0) {
     sprintf(buf, "RETR %s\n", remote);
     if (bftp_cmd(buf)) {
       i = sizeof(sin);
-      if ((d = accept(s, (struct sockaddr *) & sin, &i)) >= 0) {
+      if (Passive_FTP) {
+	d = s; s = -1;
+      }
+      else {
+	d = accept(s, (struct sockaddr *) & sin, &i);
+      }
+      if (d >= 0) {
 	if ((out = fopen(local, "w"))) {
 	  int len, k, start = time(NULL), t;
 	  float kps;
 
@@ -2273,8 +2317,9 @@
 
 int bftp_init()
 {
   Connected = 0;
+  Passive_FTP = 0;
   trans_options = bftp_options;
   trans_connect = bftp_connect;
   trans_disconnect = bftp_disconnect;
   trans_remopen = bftp_remopen;
@@ -2283,8 +2328,15 @@
 
   return 0;
 }
 
+int pftp_init()
+{
+  bftp_init();
+  Passive_FTP = 1;
+  return 0;
+}
+
 #endif
 
 /* =================================FIND CLIENT=============================== */
 #ifndef NO_FIND_CLIENT
@@ -4144,8 +4196,9 @@
 TRANSFER TransferTypes[] =
 {
 #ifndef NO_BUILTIN_FTP
   "bftp",   "Builtin FTP: Use internal ftp routines to download files     ", bftp_init,
+  "pftp",   "Passive FTP: passive-mode ftp. useful if you are firewalled  ", pftp_init,
 #endif
 #ifndef NO_EXTERNAL_FTP
   "ftp",   "External FTP: Use the 'ftp' program to download files         ", xftp_init,
 #endif