1 files changed, 165 insertions, 0 deletions

diff --git a/tcpto.c b/tcpto.c
new file mode 100644
index 0000000..8d100d5
--- /dev/null
+++ b/tcpto.c
@@ -0,0 +1,165 @@
+#include "tcpto.h"
+#include "open.h"
+#include "lock.h"
+#include "seek.h"
+#include "now.h"
+#include "ip.h"
+#include "byte.h"
+#include "datetime.h"
+#include "readwrite.h"
+
+char tcpto_buf[1024];
+
+static int flagwasthere;
+static int fdlock;
+
+static int getbuf()
+{
+ int r;
+ int fd;
+
+ fdlock = open_write("queue/lock/tcpto");
+ if (fdlock == -1) return 0;
+ fd = open_read("queue/lock/tcpto");
+ if (fd == -1) { close(fdlock); return 0; }
+ if (lock_ex(fdlock) == -1) { close(fdlock); close(fd); return 0; }
+ r = read(fd,tcpto_buf,sizeof(tcpto_buf));
+ close(fd);
+ if (r < 0) { close(fdlock); return 0; }
+ r >>= 4;
+ if (!r) close(fdlock);
+ return r;
+}
+
+int tcpto(ip) struct ip_address *ip;
+{
+ int n;
+ int i;
+ char *record;
+ datetime_sec when;
+
+ flagwasthere = 0;
+
+ n = getbuf();
+ if (!n) return 0;
+ close(fdlock);
+
+ record = tcpto_buf;
+ for (i = 0;i < n;++i)
+  {
+   if (byte_equal(ip->d,4,record))
+    {
+     flagwasthere = 1;
+     if (record[4] >= 2)
+      {
+       when = (unsigned long) (unsigned char) record[11];
+       when = (when << 8) + (unsigned long) (unsigned char) record[10];
+       when = (when << 8) + (unsigned long) (unsigned char) record[9];
+       when = (when << 8) + (unsigned long) (unsigned char) record[8];
+
+       if (now() - when < ((60 + (getpid() & 31)) << 6))
+         return 1;
+      }
+     return 0;
+    }
+   record += 16;
+  }
+ return 0;
+}
+
+void tcpto_err(ip,flagerr) struct ip_address *ip; int flagerr;
+{
+ int n;
+ int i;
+ char *record;
+ datetime_sec when;
+ datetime_sec firstwhen;
+ int firstpos;
+ datetime_sec lastwhen;
+
+ if (!flagerr)
+   if (!flagwasthere)
+     return; /* could have been added, but not worth the effort to check */
+
+ n = getbuf();
+ if (!n) return;
+
+ record = tcpto_buf;
+ for (i = 0;i < n;++i)
+  {
+   if (byte_equal(ip->d,4,record))
+    {
+     if (!flagerr)
+       record[4] = 0;
+     else
+      {
+       lastwhen = (unsigned long) (unsigned char) record[11];
+       lastwhen = (lastwhen << 8) + (unsigned long) (unsigned char) record[10];
+       lastwhen = (lastwhen << 8) + (unsigned long) (unsigned char) record[9];
+       lastwhen = (lastwhen << 8) + (unsigned long) (unsigned char) record[8];
+       when = now();
+
+       if (record[4] && (when < 120 + lastwhen)) { close(fdlock); return; }
+
+       if (++record[4] > 10) record[4] = 10;
+       record[8] = when; when >>= 8;
+       record[9] = when; when >>= 8;
+       record[10] = when; when >>= 8;
+       record[11] = when;
+      }
+     if (seek_set(fdlock,i << 4) == 0)
+       if (write(fdlock,record,16) < 16)
+         ; /*XXX*/
+     close(fdlock);
+     return;
+    }
+   record += 16;
+  }
+
+ if (!flagerr) { close(fdlock); return; }
+
+ record = tcpto_buf;
+ for (i = 0;i < n;++i)
+  {
+   if (!record[4]) break;
+   record += 16;
+  }
+
+ if (i >= n)
+  {
+   firstpos = -1;
+   record = tcpto_buf;
+   for (i = 0;i < n;++i)
+    {
+     when = (unsigned long) (unsigned char) record[11];
+     when = (when << 8) + (unsigned long) (unsigned char) record[10];
+     when = (when << 8) + (unsigned long) (unsigned char) record[9];
+     when = (when << 8) + (unsigned long) (unsigned char) record[8];
+     when += (record[4] << 10);
+     if ((firstpos < 0) || (when < firstwhen))
+      {
+       firstpos = i;
+       firstwhen = when;
+      }
+     record += 16;
+    }
+   i = firstpos;
+  }
+
+ if (i >= 0)
+  {
+   record = tcpto_buf + (i << 4);
+   byte_copy(record,4,ip->d);
+   when = now();
+   record[8] = when; when >>= 8;
+   record[9] = when; when >>= 8;
+   record[10] = when; when >>= 8;
+   record[11] = when;
+   record[4] = 1;
+   if (seek_set(fdlock,i << 4) == 0)
+     if (write(fdlock,record,16) < 16)
+       ; /*XXX*/
+  }
+
+ close(fdlock);
+}