[PATCH] realrcptto

1 files changed, 421 insertions, 0 deletions

diff --git a/realrcptto.c b/realrcptto.c
new file mode 100644
index 0000000..7ec331a
--- /dev/null
+++ b/realrcptto.c
@@ -0,0 +1,421 @@
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <pwd.h>
+#include "auto_break.h"
+#include "auto_usera.h"
+#include "byte.h"
+#include "case.h"
+#include "cdb.h"
+#include "constmap.h"
+#include "error.h"
+#include "fmt.h"
+#include "open.h"
+#include "str.h"
+#include "stralloc.h"
+#include "uint32.h"
+#include "substdio.h"
+#include "env.h"
+#include "slurpclose.h"
+
+extern void die_nomem();
+extern void die_control();
+extern void die_cdb();
+extern void die_sys();
+
+static stralloc envnoathost = {0};
+static stralloc percenthack = {0};
+static stralloc locals = {0};
+static stralloc vdoms = {0};
+static struct constmap mappercenthack;
+static struct constmap maplocals;
+static struct constmap mapvdoms;
+
+static char *dash;
+static char *extension;
+static char *local;
+static struct passwd *pw;
+
+static char errbuf[128];
+static struct substdio sserr = SUBSTDIO_FDBUF(write,2,errbuf,sizeof errbuf);
+
+static char pidbuf[64];
+static char remoteipbuf[64]=" ";
+
+static int flagdenyall;
+static int flagdenyany;
+
+void realrcptto_init()
+{
+  char *x;
+
+  if (control_rldef(&envnoathost,"control/envnoathost",1,"envnoathost") != 1)
+    die_control();
+
+  if (control_readfile(&locals,"control/locals",1) != 1) die_control();
+  if (!constmap_init(&maplocals,locals.s,locals.len,0)) die_nomem();
+  switch(control_readfile(&percenthack,"control/percenthack",0)) {
+    case -1: die_control();
+    case 0: if (!constmap_init(&mappercenthack,"",0,0)) die_nomem();
+    case 1:
+      if (!constmap_init(&mappercenthack,percenthack.s,percenthack.len,0))
+        die_nomem();
+  }
+  switch(control_readfile(&vdoms,"control/virtualdomains",0)) {
+    case -1: die_control();
+    case 0: if (!constmap_init(&mapvdoms,"",0,1)) die_nomem();
+    case 1: if (!constmap_init(&mapvdoms,vdoms.s,vdoms.len,1)) die_nomem();
+  }
+
+  str_copy(pidbuf + fmt_ulong(pidbuf,getpid())," ");
+  x=env_get("PROTO");
+  if (x) {
+    static char const remoteip[]="REMOTEIP";
+    unsigned int len = str_len(x);
+    if (len <= sizeof remoteipbuf - sizeof remoteip) {
+      byte_copy(remoteipbuf,len,x);
+      byte_copy(remoteipbuf + len,sizeof remoteip,remoteip);
+      x = env_get(remoteipbuf);
+      len = str_len(x);
+      if (len + 1 < sizeof remoteipbuf) {
+        byte_copy(remoteipbuf,len,x);
+        remoteipbuf[len]=' ';
+        remoteipbuf[len + 1]='\0';
+      }
+    }
+  }
+
+  x = env_get("QMAILRRTDENYALL");
+  flagdenyall = (x && x[0]=='1' && x[1]=='\0');
+}
+
+void realrcptto_start()
+{
+  flagdenyany = 0;
+}
+
+static int denyaddr(addr, depth)
+char *addr;
+int depth;
+{
+  if (depth == 1)
+  {
+    substdio_puts(&sserr,"realrcptto ");
+    substdio_puts(&sserr,pidbuf);
+    substdio_puts(&sserr,remoteipbuf);
+    substdio_puts(&sserr,addr);
+    substdio_puts(&sserr,"\n");
+    substdio_flush(&sserr);
+    flagdenyany = 1;
+  }
+  return flagdenyall;
+}
+
+static void stat_error(path,error)
+char* path;
+int error;
+{
+  substdio_puts(&sserr,"unable to stat ");
+  substdio_puts(&sserr,path);
+  substdio_puts(&sserr,": ");
+  substdio_puts(&sserr,error_str(error));
+  substdio_puts(&sserr,"\n");
+  substdio_flush(&sserr);
+}
+
+#define GETPW_USERLEN 32
+
+static int userext()
+{
+  char username[GETPW_USERLEN];
+  struct stat st;
+
+  extension = local + str_len(local);
+  for (;;) {
+    if (extension - local < sizeof(username))
+      if (!*extension || (*extension == *auto_break)) {
+        byte_copy(username,extension - local,local);
+        username[extension - local] = 0;
+        case_lowers(username);
+        errno = 0;
+        pw = getpwnam(username);
+        if (errno == error_txtbsy) die_sys();
+        if (pw)
+          if (pw->pw_uid)
+            if (stat(pw->pw_dir,&st) == 0) {
+              if (st.st_uid == pw->pw_uid) {
+                dash = "";
+                if (*extension) { ++extension; dash = "-"; }
+                return 1;
+              }
+            }
+            else
+              if (error_temp(errno)) die_sys();
+      }
+    if (extension == local) return 0;
+    --extension;
+  }
+}
+
+// max lookups
+#define MAXRECURSION 5
+
+static int handleqme(qme, depth)
+stralloc *qme;
+int depth;
+{
+  stralloc cmds = {0};
+  char *username = NULL;
+  int fd, i, j, k, count;
+
+  if (depth >= MAXRECURSION) return 0;
+  if (!stralloc_ready(&cmds,0)) die_nomem();
+  cmds.len = 0;
+
+  fd = open_read(qme->s);
+  if (fd == -1) return 0;
+  if (slurpclose(fd,&cmds,256) == -1) die_nomem();
+  if (!cmds.len || (cmds.s[cmds.len - 1] != '\n'))
+    if (!stralloc_cats(&cmds,"\n")) die_nomem();
+
+  i = count = 0;
+  for (j = 0;j < cmds.len;++j)
+  {
+    if (cmds.s[j] == '\n')
+    {
+      cmds.s[j] = 0;
+      k = j;
+      while ((k > i) && ((cmds.s[k - 1] == ' ') || (cmds.s[k - 1] == '\t')))
+        cmds.s[--k] = 0;
+      switch(cmds.s[i])
+      {
+        case 0:
+        case '#':
+        case '.':
+        case '/':
+        case '|':
+        case '+':
+          break;
+        case '&':
+          ++i;
+        default:
+          count++;
+          username = cmds.s + i;
+          break;
+      }
+      i = j + 1;
+    }
+  }
+
+  if (count == 1 && username)
+    realrcptto(username, ++depth);
+
+  return 1;
+}
+
+int realrcptto(addr, depth)
+char *addr;
+int depth;
+{
+  env_unset("DTUSER");
+  return realrcptto_ex(addr, depth);
+}
+
+int realrcptto_ex(addr, depth)
+char *addr;
+int depth;
+{
+  char *homedir, *username;
+  static stralloc localpart = {0};
+  static stralloc lower = {0};
+  static stralloc nughde = {0};
+  static stralloc wildchars = {0};
+  static stralloc safeext = {0};
+  static stralloc qme = {0};
+  unsigned int i,at;
+
+  /* Short circuit, or full logging?  Short circuit. */
+  if (flagdenyall && flagdenyany) return 1;
+
+  /* qmail-send:rewrite */
+  if (!stralloc_copys(&localpart,addr)) die_nomem();
+  i = byte_rchr(localpart.s,localpart.len,'@');
+  if (i == localpart.len) {
+    if (!stralloc_cats(&localpart,"@")) die_nomem();
+    if (!stralloc_cat(&localpart,&envnoathost)) die_nomem();
+  }
+  while (constmap(&mappercenthack,localpart.s + i + 1,localpart.len - i - 1)) {
+    unsigned int j = byte_rchr(localpart.s,i,'%');
+    if (j == i) break;
+    localpart.len = i;
+    i = j;
+    localpart.s[i] = '@';
+  }
+  at = byte_rchr(localpart.s,localpart.len,'@');
+  if (constmap(&maplocals,localpart.s + at + 1,localpart.len - at - 1)) {
+    localpart.len = at;
+    localpart.s[at] = '\0';
+  } else {
+    unsigned int xlen,newlen;
+    char *x;
+    for (i = 0;;++i) {
+      if (i > localpart.len) return denyaddr(addr, depth);
+      if (!i || (i == at + 1) || (i == localpart.len) ||
+          ((i > at) && (localpart.s[i] == '.'))) {
+        x = constmap(&mapvdoms,localpart.s + i,localpart.len - i);
+        if (x && i == at + 1) {
+          // set QMAILQUEUE if catch-all
+          char *qmailqueue;
+          qmailqueue = env_get("QMAILQUEUE");
+          if (qmailqueue) {
+            if (!env_put("QMAILQUEUE=bin/qmail-queue")) die_nomem();
+          }
+        }
+        if (x) break;
+      }
+    }
+    if (!*x) return 1;
+    xlen = str_len(x) + 1;  /* +1 for '-' */
+    newlen = xlen + at + 1; /* +1 for \0 */
+    if (xlen < 1 || newlen - 1 < xlen || newlen < 1 ||
+        !stralloc_ready(&localpart,newlen))
+      die_nomem();
+    localpart.s[newlen - 1] = '\0';
+    byte_copyr(localpart.s + xlen,at,localpart.s);
+    localpart.s[xlen - 1] = '-';
+    byte_copy(localpart.s,xlen - 1,x);
+    localpart.len = newlen;
+  }
+
+  /* qmail-lspawn:nughde_get */
+  {
+    int r,fd,flagwild;
+    if (!stralloc_copys(&lower,"!")) die_nomem();
+    if (!stralloc_cats(&lower,localpart.s)) die_nomem();
+    if (!stralloc_0(&lower)) die_nomem();
+    case_lowerb(lower.s,lower.len);
+    if (!stralloc_copys(&nughde,"")) die_nomem();
+    fd = open_read("users/cdb");
+    if (fd == -1) {
+      if (errno != error_noent) die_cdb();
+    } else {
+      uint32 dlen;
+      r = cdb_seek(fd,"",0,&dlen);
+      if (r != 1) die_cdb();
+      if (!stralloc_ready(&wildchars,(unsigned int) dlen)) die_nomem();
+      wildchars.len = dlen;
+      if (cdb_bread(fd,wildchars.s,wildchars.len) == -1) die_cdb();
+      i = lower.len;
+      flagwild = 0;
+      do { /* i > 0 */
+        if (!flagwild || (i == 1) ||
+            (byte_chr(wildchars.s,wildchars.len,lower.s[i - 1])
+             < wildchars.len)) {
+          r = cdb_seek(fd,lower.s,i,&dlen);
+          if (r == -1) die_cdb();
+          if (r == 1) {
+            char *x;
+            if (!stralloc_ready(&nughde,(unsigned int) dlen)) die_nomem();
+            nughde.len = dlen;
+            if (cdb_bread(fd,nughde.s,nughde.len) == -1) die_cdb();
+            if (flagwild)
+              if (!stralloc_cats(&nughde,localpart.s + i - 1)) die_nomem();
+            if (!stralloc_0(&nughde)) die_nomem();
+            close(fd);
+            x=nughde.s;
+            /* skip username */
+            username=x;
+            x += byte_chr(x,nughde.s + nughde.len - x,'\0');
+            if (x == nughde.s + nughde.len) return 1;
+            ++x;
+            /* skip uid */
+            x += byte_chr(x,nughde.s + nughde.len - x,'\0');
+            if (x == nughde.s + nughde.len) return 1;
+            ++x;
+            /* skip gid */
+            x += byte_chr(x,nughde.s + nughde.len - x,'\0');
+            if (x == nughde.s + nughde.len) return 1;
+            ++x;
+            /* skip homedir */
+            homedir=x;
+            x += byte_chr(x,nughde.s + nughde.len - x,'\0');
+            if (x == nughde.s + nughde.len) return 1;
+            ++x;
+            /* skip dash */
+            dash=x;
+            x += byte_chr(x,nughde.s + nughde.len - x,'\0');
+            if (x == nughde.s + nughde.len) return 1;
+            ++x;
+            extension=x;
+            goto got_nughde;
+          }
+        }
+        --i;
+        flagwild = 1;
+      } while (i);
+      close(fd);
+    }
+  }
+
+  /* qmail-getpw */
+  local = localpart.s;
+  if (!userext()) {
+    extension = local;
+    dash = "-";
+    pw = getpwnam(auto_usera);
+  }
+  if (!pw) return denyaddr(addr, depth);
+  if (!stralloc_copys(&nughde,pw->pw_dir)) die_nomem();
+  if (!stralloc_0(&nughde)) die_nomem();
+  homedir=nughde.s;
+  username=pw->pw_name;
+
+  got_nughde:
+
+  /* qmail-local:qmesearch */
+  //if (!*dash) return 1;
+  if (!*dash) { env_put2("DTUSER", username); return 1; }
+  if (!stralloc_copys(&safeext,extension)) die_nomem();
+  case_lowerb(safeext.s,safeext.len);
+  for (i = 0;i < safeext.len;++i)
+  {
+    if (safeext.s[i] == '.')
+      safeext.s[i] = ':';
+  }
+  {
+    struct stat st;
+    int i;
+    if (!stralloc_copys(&qme,homedir)) die_nomem();
+    if (!stralloc_cats(&qme,"/.qmail")) die_nomem();
+    if (!stralloc_cats(&qme,dash)) die_nomem();
+    if (!stralloc_cat(&qme,&safeext)) die_nomem();
+    if (!stralloc_0(&qme)) die_nomem();
+    //if (stat(qme.s,&st) == 0) return 1;
+    if (stat(qme.s,&st) == 0) { handleqme(&qme, depth); return 1; }
+    if (errno != error_noent) {
+      stat_error(qme.s,errno);
+      return 1;
+    }
+    for (i = safeext.len;i >= 0;--i)
+      if (!i || (safeext.s[i - 1] == '-')) {
+        if (!stralloc_copys(&qme,homedir)) die_nomem();
+        if (!stralloc_cats(&qme,"/.qmail")) die_nomem();
+        if (!stralloc_cats(&qme,dash)) die_nomem();
+        if (!stralloc_catb(&qme,safeext.s,i)) die_nomem();
+        if (!stralloc_cats(&qme,"default")) die_nomem();
+        if (!stralloc_0(&qme)) die_nomem();
+        //if (stat(qme.s,&st) == 0) return 1;
+        if (stat(qme.s,&st) == 0) { handleqme(&qme, depth); return 1; }
+        if (errno != error_noent) {
+          stat_error(qme.s,errno);
+          return 1;
+        }
+      }
+    return denyaddr(addr, depth);
+  }
+}
+
+int realrcptto_deny()
+{
+  return flagdenyall && flagdenyany;
+}