bare beginnings of a greylisting system

1 files changed, 60 insertions, 51 deletions

diff --git a/tools/hi-q.c b/tools/hi-q.c
index 2ddc448..21724a1 100644
--- a/tools/hi-q.c
+++ b/tools/hi-q.c
@@ -11,7 +11,7 @@
 
 #include <unistd.h>
 #include <stdlib.h>             /* for exit(), getenv() */
-#include <stdio.h>
+#include <stdio.h>              /* for perror */
 #include <errno.h>
 #include <sys/types.h>          /* for fork(), wait() */
 #include <sys/stat.h>
@@ -29,6 +29,7 @@ using namespace std;
 //  error exit codes, mostly as stated in qmail.c
 const int ex_good = 0;
 const int ex_spam = 21;
+const int ex_grey = 70;
 const int ex_syserr = 71;
 const int ex_comerr = 74;
 
@@ -139,7 +140,7 @@ int xclose(int arg){
 
 extern char** environ;
 
-typedef enum {gray, black, qq, fail} moder;
+typedef enum {grey, black, qq, fail} moder;
 
 class jobber{
 public:
@@ -161,8 +162,8 @@ public:
 
   void setmode(const string _mode) {
     if (0) {}
-    else if (_mode == "gray")  mode = gray;
-    else if (_mode == "grey")  mode = gray;     // variant spelling
+    else if (_mode == "gray")  mode = grey;
+    else if (_mode == "grey")  mode = grey;     // variant spelling
     else if (_mode == "black") mode = black;
     else if (_mode == "qq") mode = qq;
     else {
@@ -175,8 +176,8 @@ public:
 int main(int argc, char** argv) {
   progname = *argv;
   mypid = getpid();
-  dump("TCPREMOTEIP");
-  dump("TCPREMOTEHOST");
+//  dump("TCPREMOTEIP");
+//  dump("TCPREMOTEHOST");
   int verbose(0);
   int kidstatus;
 
@@ -270,41 +271,44 @@ int main(int argc, char** argv) {
 //     to close it and dup() something useful onto it.
 
   map<int,int> iiofpid;
-  for (unsigned int ii=0; ii < nkids; ii++){  /* loop starting all kids */
-    int datapipe[2];
-    int kid_end;
 
+  for (unsigned int ii=0; ii < nkids; ii++){  /* loop starting all kids */
 //xx fprintf(stderr, "Top of loop %d loose: %d\n", ii, loose_end);
 
-    if (loose_end) {
-      close(0);
-      dup2(loose_end, 0);
-      close(loose_end);
-    }
+    int kid_end;
+    if (filter[ii].mode != grey){
+      int datapipe[2];
 
-// Create a pipe, which will be used to connect
-// this child's fd1 to the next child's fd0 ...
-// except for the last kid, which reads both fd0 and fd1,
-// while writing nothing.
+      if (loose_end) {
+        close(0);
+        dup2(loose_end, 0);
+        close(loose_end);
+      }
 
-    rslt = pipe(datapipe);
-    if (rslt < 0) {
-      fprintf(stderr, "hi-q: could not create datapipe: ");
-      perror(0);
-      panic(ex_syserr);
-    }
+  // Create a pipe, which will be used to connect
+  // this child's fd1 to the next child's fd0 ...
+  // except for the last kid, which reads both fd0 and fd1,
+  // while writing nothing.
 
-//xx fprintf(stderr, "pipe: %d %d\n", datapipe[0], datapipe[1]);
+      rslt = pipe(datapipe);
+      if (rslt < 0) {
+        fprintf(stderr, "hi-q: could not create datapipe: ");
+        perror(0);
+        panic(ex_syserr);
+      }
 
-// For N-1 kids, the loose end feeds forward.
-//    It will be written by this kid and read by the next kid.
-// For the last kid, the loose end connects to hi-q.
-//    It will be written by hi-q and read by the last kid.
+  //xx fprintf(stderr, "pipe: %d %d\n", datapipe[0], datapipe[1]);
 
-    int lastkid = (ii == nkids-1);
-#define flip(a,b) (lastkid ? b : a)
-    loose_end = datapipe[flip(rEnd, wEnd)];
-    kid_end   = datapipe[flip(wEnd, rEnd)];
+  // For N-1 kids, the loose end feeds forward.
+  //    It will be written by this kid and read by the next kid.
+  // For the last kid, the loose end connects to hi-q.
+  //    It will be written by hi-q and read by the last kid.
+
+      int lastkid = (ii == nkids-1);
+  #define flip(a,b) (lastkid ? b : a)
+      loose_end = datapipe[flip(rEnd, wEnd)];
+      kid_end   = datapipe[flip(wEnd, rEnd)];
+    }
 
     kidpid[ii] = fork();
     if (kidpid[ii] == -1) {
@@ -358,24 +362,23 @@ int main(int argc, char** argv) {
         }
       }
 
-// Now that we are through creating pipes, we don't
-// need to continue blocking fd1:
-      close(1);
-
-      close(loose_end);          // the reading end is none of this kid's business
-                                // except last kid:  writing end
+      if (filter[ii].mode != grey){
+        close(loose_end);          // the reading end is none of this kid's business
+                                  // except last kid:  writing end
+
+  // Note this does an implicit close on the previously-open fd1:
+        rslt = dup2(kid_end, 1);   // the writing end is stdout for this kid
+                                  // except last kid:  nonstandard input
+        if (rslt < 0) {
+          fprintf(stderr, "hi-q: kid %d: dup2(%d,1) failed: ", ii, kid_end);
+          perror(0);
+          exit(ex_syserr);
+        }
 
-      rslt = dup2(kid_end, 1);   // the writing end is stdout for this kid
-                                // except last kid:  nonstandard input
-      if (rslt < 0) {
-        fprintf(stderr, "hi-q: kid %d: dup2(%d,1) failed: ", ii, kid_end);
-        perror(0);
-        exit(ex_syserr);
+        close(kid_end);           // use fd1 instead now
+        // OK, at this point this kid is set up to read fd0 and write fd1
+        // (except last kid reads fd1 as well as fd0).
       }
-
-      close(kid_end);           // use fd1 instead now
-      // OK, at this point this kid is set up to read fd0 and write fd1
-      // (except last kid reads fd1 as well as fd0).
 ////  probe_fd();
 
       int ntok = filter[ii].cmd.size();
@@ -499,14 +502,20 @@ int main(int argc, char** argv) {
   if (best_blame) {
     string short_name("");
     int kidno(iiofpid[argbest_blame]);
+    string exword = "spam";
+    int excode = ex_spam;
+    if (filter[kidno].mode == grey) {
+      exword = "greylisting";
+      excode = ex_grey;
+    }
     if (WIFEXITED(best_blame)) {
       int sts = WEXITSTATUS(best_blame);
       if (sts == 1) {
         cerr << "hi-q says: kid[" << kidno << "]"
            << " pid " << argbest_blame
            << " i.e. '" << filter[kidno].cmd[0] << "'"
-           << " reports spam." << endl;
-        panic(ex_spam);
+           << " reports " << exword << endl;
+        panic(excode);
       }
       if (sts != 0) {
         cerr << "hi-q says: kid " << argbest_blame