--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/qmail-remote.c	Fri Oct 19 14:06:22 2007 +0200
@@ -0,0 +1,427 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include "sig.h"
+#include "stralloc.h"
+#include "substdio.h"
+#include "subfd.h"
+#include "scan.h"
+#include "case.h"
+#include "error.h"
+#include "auto_qmail.h"
+#include "control.h"
+#include "dns.h"
+#include "alloc.h"
+#include "quote.h"
+#include "ip.h"
+#include "ipalloc.h"
+#include "ipme.h"
+#include "gen_alloc.h"
+#include "gen_allocdefs.h"
+#include "str.h"
+#include "now.h"
+#include "exit.h"
+#include "constmap.h"
+#include "tcpto.h"
+#include "readwrite.h"
+#include "timeoutconn.h"
+#include "timeoutread.h"
+#include "timeoutwrite.h"
+
+#define HUGESMTPTEXT 5000
+
+#define PORT_SMTP 25 /* silly rabbit, /etc/services is for users */
+unsigned long port = PORT_SMTP;
+
+GEN_ALLOC_typedef(saa,stralloc,sa,len,a)
+GEN_ALLOC_readyplus(saa,stralloc,sa,len,a,i,n,x,10,saa_readyplus)
+static stralloc sauninit = {0};
+
+stralloc helohost = {0};
+stralloc routes = {0};
+struct constmap maproutes;
+stralloc host = {0};
+stralloc sender = {0};
+
+saa reciplist = {0};
+
+struct ip_address partner;
+
+void out(s) char *s; { if (substdio_puts(subfdoutsmall,s) == -1) _exit(0); }
+void zero() { if (substdio_put(subfdoutsmall,"\0",1) == -1) _exit(0); }
+void zerodie() { zero(); substdio_flush(subfdoutsmall); _exit(0); }
+void outsafe(sa) stralloc *sa; { int i; char ch;
+for (i = 0;i < sa->len;++i) {
+ch = sa->s[i]; if (ch < 33) ch = '?'; if (ch > 126) ch = '?';
+if (substdio_put(subfdoutsmall,&ch,1) == -1) _exit(0); } }
+
+void temp_nomem() { out("ZOut of memory. (#4.3.0)\n"); zerodie(); }
+void temp_oserr() { out("Z\
+System resources temporarily unavailable. (#4.3.0)\n"); zerodie(); }
+void temp_noconn() { out("Z\
+Sorry, I wasn't able to establish an SMTP connection. (#4.4.1)\n"); zerodie(); }
+void temp_read() { out("ZUnable to read message. (#4.3.0)\n"); zerodie(); }
+void temp_dnscanon() { out("Z\
+CNAME lookup failed temporarily. (#4.4.3)\n"); zerodie(); }
+void temp_dns() { out("Z\
+Sorry, I couldn't find any host by that name. (#4.1.2)\n"); zerodie(); }
+void temp_chdir() { out("Z\
+Unable to switch to home directory. (#4.3.0)\n"); zerodie(); }
+void temp_control() { out("Z\
+Unable to read control files. (#4.3.0)\n"); zerodie(); }
+void perm_partialline() { out("D\
+SMTP cannot transfer messages with partial final lines. (#5.6.2)\n"); zerodie(); }
+void perm_usage() { out("D\
+I (qmail-remote) was invoked improperly. (#5.3.5)\n"); zerodie(); }
+void perm_dns() { out("D\
+Sorry, I couldn't find any host named ");
+outsafe(&host);
+out(". (#5.1.2)\n"); zerodie(); }
+void perm_nomx() { out("D\
+Sorry, I couldn't find a mail exchanger or IP address. (#5.4.4)\n");
+zerodie(); }
+void perm_ambigmx() { out("D\
+Sorry. Although I'm listed as a best-preference MX or A for that host,\n\
+it isn't in my control/locals file, so I don't treat it as local. (#5.4.6)\n");
+zerodie(); }
+
+void outhost()
+{
+  char x[IPFMT];
+  if (substdio_put(subfdoutsmall,x,ip_fmt(x,&partner)) == -1) _exit(0);
+}
+
+int flagcritical = 0;
+
+void dropped() {
+  out("ZConnected to ");
+  outhost();
+  out(" but connection died. ");
+  if (flagcritical) out("Possible duplicate! ");
+  out("(#4.4.2)\n");
+  zerodie();
+}
+
+int timeoutconnect = 60;
+int smtpfd;
+int timeout = 1200;
+
+int saferead(fd,buf,len) int fd; char *buf; int len;
+{
+  int r;
+  r = timeoutread(timeout,smtpfd,buf,len);
+  if (r <= 0) dropped();
+  return r;
+}
+int safewrite(fd,buf,len) int fd; char *buf; int len;
+{
+  int r;
+  r = timeoutwrite(timeout,smtpfd,buf,len);
+  if (r <= 0) dropped();
+  return r;
+}
+
+char inbuf[1024];
+substdio ssin = SUBSTDIO_FDBUF(read,0,inbuf,sizeof inbuf);
+char smtptobuf[1024];
+substdio smtpto = SUBSTDIO_FDBUF(safewrite,-1,smtptobuf,sizeof smtptobuf);
+char smtpfrombuf[128];
+substdio smtpfrom = SUBSTDIO_FDBUF(saferead,-1,smtpfrombuf,sizeof smtpfrombuf);
+
+stralloc smtptext = {0};
+
+void get(ch)
+char *ch;
+{
+  substdio_get(&smtpfrom,ch,1);
+  if (*ch != '\r')
+    if (smtptext.len < HUGESMTPTEXT)
+     if (!stralloc_append(&smtptext,ch)) temp_nomem();
+}
+
+unsigned long smtpcode()
+{
+  unsigned char ch;
+  unsigned long code;
+
+  if (!stralloc_copys(&smtptext,"")) temp_nomem();
+
+  get(&ch); code = ch - '0';
+  get(&ch); code = code * 10 + (ch - '0');
+  get(&ch); code = code * 10 + (ch - '0');
+  for (;;) {
+    get(&ch);
+    if (ch != '-') break;
+    while (ch != '\n') get(&ch);
+    get(&ch);
+    get(&ch);
+    get(&ch);
+  }
+  while (ch != '\n') get(&ch);
+
+  return code;
+}
+
+void outsmtptext()
+{
+  int i; 
+  if (smtptext.s) if (smtptext.len) {
+    out("Remote host said: ");
+    for (i = 0;i < smtptext.len;++i)
+      if (!smtptext.s[i]) smtptext.s[i] = '?';
+    if (substdio_put(subfdoutsmall,smtptext.s,smtptext.len) == -1) _exit(0);
+    smtptext.len = 0;
+  }
+}
+
+void quit(prepend,append)
+char *prepend;
+char *append;
+{
+  substdio_putsflush(&smtpto,"QUIT\r\n");
+  /* waiting for remote side is just too ridiculous */
+  out(prepend);
+  outhost();
+  out(append);
+  out(".\n");
+  outsmtptext();
+  zerodie();
+}
+
+void blast()
+{
+  int r;
+  char ch;
+
+  for (;;) {
+    r = substdio_get(&ssin,&ch,1);
+    if (r == 0) break;
+    if (r == -1) temp_read();
+    if (ch == '.')
+      substdio_put(&smtpto,".",1);
+    while (ch != '\n') {
+      substdio_put(&smtpto,&ch,1);
+      r = substdio_get(&ssin,&ch,1);
+      if (r == 0) perm_partialline();
+      if (r == -1) temp_read();
+    }
+    substdio_put(&smtpto,"\r\n",2);
+  }
+ 
+  flagcritical = 1;
+  substdio_put(&smtpto,".\r\n",3);
+  substdio_flush(&smtpto);
+}
+
+stralloc recip = {0};
+
+void smtp()
+{
+  unsigned long code;
+  int flagbother;
+  int i;
+ 
+  if (smtpcode() != 220) quit("ZConnected to "," but greeting failed");
+ 
+  substdio_puts(&smtpto,"HELO ");
+  substdio_put(&smtpto,helohost.s,helohost.len);
+  substdio_puts(&smtpto,"\r\n");
+  substdio_flush(&smtpto);
+  if (smtpcode() != 250) quit("ZConnected to "," but my name was rejected");
+ 
+  substdio_puts(&smtpto,"MAIL FROM:<");
+  substdio_put(&smtpto,sender.s,sender.len);
+  substdio_puts(&smtpto,">\r\n");
+  substdio_flush(&smtpto);
+  code = smtpcode();
+  if (code >= 500) quit("DConnected to "," but sender was rejected");
+  if (code >= 400) quit("ZConnected to "," but sender was rejected");
+ 
+  flagbother = 0;
+  for (i = 0;i < reciplist.len;++i) {
+    substdio_puts(&smtpto,"RCPT TO:<");
+    substdio_put(&smtpto,reciplist.sa[i].s,reciplist.sa[i].len);
+    substdio_puts(&smtpto,">\r\n");
+    substdio_flush(&smtpto);
+    code = smtpcode();
+    if (code >= 500) {
+      out("h"); outhost(); out(" does not like recipient.\n");
+      outsmtptext(); zero();
+    }
+    else if (code >= 400) {
+      out("s"); outhost(); out(" does not like recipient.\n");
+      outsmtptext(); zero();
+    }
+    else {
+      out("r"); zero();
+      flagbother = 1;
+    }
+  }
+  if (!flagbother) quit("DGiving up on ","");
+ 
+  substdio_putsflush(&smtpto,"DATA\r\n");
+  code = smtpcode();
+  if (code >= 500) quit("D"," failed on DATA command");
+  if (code >= 400) quit("Z"," failed on DATA command");
+ 
+  blast();
+  code = smtpcode();
+  flagcritical = 0;
+  if (code >= 500) quit("D"," failed after I sent the message");
+  if (code >= 400) quit("Z"," failed after I sent the message");
+  quit("K"," accepted message");
+}
+
+stralloc canonhost = {0};
+stralloc canonbox = {0};
+
+void addrmangle(saout,s,flagalias,flagcname)
+stralloc *saout; /* host has to be canonical, box has to be quoted */
+char *s;
+int *flagalias;
+int flagcname;
+{
+  int j;
+ 
+  *flagalias = flagcname;
+ 
+  j = str_rchr(s,'@');
+  if (!s[j]) {
+    if (!stralloc_copys(saout,s)) temp_nomem();
+    return;
+  }
+  if (!stralloc_copys(&canonbox,s)) temp_nomem();
+  canonbox.len = j;
+  if (!quote(saout,&canonbox)) temp_nomem();
+  if (!stralloc_cats(saout,"@")) temp_nomem();
+ 
+  if (!stralloc_copys(&canonhost,s + j + 1)) temp_nomem();
+  if (flagcname)
+    switch(dns_cname(&canonhost)) {
+      case 0: *flagalias = 0; break;
+      case DNS_MEM: temp_nomem();
+      case DNS_SOFT: temp_dnscanon();
+      case DNS_HARD: ; /* alias loop, not our problem */
+    }
+
+  if (!stralloc_cat(saout,&canonhost)) temp_nomem();
+}
+
+void getcontrols()
+{
+  if (control_init() == -1) temp_control();
+  if (control_readint(&timeout,"control/timeoutremote") == -1) temp_control();
+  if (control_readint(&timeoutconnect,"control/timeoutconnect") == -1)
+    temp_control();
+  if (control_rldef(&helohost,"control/helohost",1,(char *) 0) != 1)
+    temp_control();
+  switch(control_readfile(&routes,"control/smtproutes",0)) {
+    case -1:
+      temp_control();
+    case 0:
+      if (!constmap_init(&maproutes,"",0,1)) temp_nomem(); break;
+    case 1:
+      if (!constmap_init(&maproutes,routes.s,routes.len,1)) temp_nomem(); break;
+  }
+}
+
+void main(argc,argv)
+int argc;
+char **argv;
+{
+  static ipalloc ip = {0};
+  int i;
+  unsigned long random;
+  char **recips;
+  unsigned long prefme;
+  int flagallaliases;
+  int flagalias;
+  char *relayhost;
+ 
+  sig_pipeignore();
+  if (argc < 4) perm_usage();
+  if (chdir(auto_qmail) == -1) temp_chdir();
+  getcontrols();
+ 
+ 
+  if (!stralloc_copys(&host,argv[1])) temp_nomem();
+ 
+  relayhost = 0;
+  for (i = 0;i <= host.len;++i)
+    if ((i == 0) || (i == host.len) || (host.s[i] == '.'))
+      if (relayhost = constmap(&maproutes,host.s + i,host.len - i))
+        break;
+  if (relayhost && !*relayhost) relayhost = 0;
+ 
+  if (relayhost) {
+    i = str_chr(relayhost,':');
+    if (relayhost[i]) {
+      scan_ulong(relayhost + i + 1,&port);
+      relayhost[i] = 0;
+    }
+    if (!stralloc_copys(&host,relayhost)) temp_nomem();
+  }
+
+
+  addrmangle(&sender,argv[2],&flagalias,0);
+ 
+  if (!saa_readyplus(&reciplist,0)) temp_nomem();
+  if (ipme_init() != 1) temp_oserr();
+ 
+  flagallaliases = 1;
+  recips = argv + 3;
+  while (*recips) {
+    if (!saa_readyplus(&reciplist,1)) temp_nomem();
+    reciplist.sa[reciplist.len] = sauninit;
+    addrmangle(reciplist.sa + reciplist.len,*recips,&flagalias,!relayhost);
+    if (!flagalias) flagallaliases = 0;
+    ++reciplist.len;
+    ++recips;
+  }
+
+ 
+  random = now() + (getpid() << 16);
+  switch (relayhost ? dns_ip(&ip,&host) : dns_mxip(&ip,&host,random)) {
+    case DNS_MEM: temp_nomem();
+    case DNS_SOFT: temp_dns();
+    case DNS_HARD: perm_dns();
+    case 1:
+      if (ip.len <= 0) temp_dns();
+  }
+ 
+  if (ip.len <= 0) perm_nomx();
+ 
+  prefme = 100000;
+  for (i = 0;i < ip.len;++i)
+    if (ipme_is(&ip.ix[i].ip))
+      if (ip.ix[i].pref < prefme)
+        prefme = ip.ix[i].pref;
+ 
+  if (relayhost) prefme = 300000;
+  if (flagallaliases) prefme = 500000;
+ 
+  for (i = 0;i < ip.len;++i)
+    if (ip.ix[i].pref < prefme)
+      break;
+ 
+  if (i >= ip.len)
+    perm_ambigmx();
+ 
+  for (i = 0;i < ip.len;++i) if (ip.ix[i].pref < prefme) {
+    if (tcpto(&ip.ix[i].ip)) continue;
+ 
+    smtpfd = socket(AF_INET,SOCK_STREAM,0);
+    if (smtpfd == -1) temp_oserr();
+ 
+    if (timeoutconn(smtpfd,&ip.ix[i].ip,(unsigned int) port,timeoutconnect) == 0) {
+      tcpto_err(&ip.ix[i].ip,0);
+      partner = ip.ix[i].ip;
+      smtp(); /* does not return */
+    }
+    tcpto_err(&ip.ix[i].ip,errno == error_timeout);
+    close(smtpfd);
+  }
+  
+  temp_noconn();
+}