mdw@git.distorted.org.uk Git - qmail/blob - spawn.c

   1 #include <sys/types.h>
   2 #include <sys/stat.h>
   3 #include "sig.h"
   4 #include "wait.h"
   5 #include "substdio.h"
   6 #include "byte.h"
   7 #include "str.h"
   8 #include "stralloc.h"
   9 #include "select.h"
  10 #include "exit.h"
  11 #include "coe.h"
  12 #include "open.h"
  13 #include "error.h"
  14 #include "auto_qmail.h"
  15 #include "auto_uids.h"
  16 #include "auto_spawn.h"
  17
  18 extern int truncreport;
  19 extern int spawn();
  20 extern void report();
  21 extern void initialize();
  22
  23 struct delivery
  24  {
  25   int used;
  26   int fdin; /* pipe input */
  27   int pid; /* zero if child is dead */
  28   int wstat; /* if !pid: status of child */
  29   int fdout; /* pipe output, -1 if !pid; delays eof until after death */
  30   stralloc output;
  31  }
  32 ;
  33
  34 struct delivery *d;
  35
  36 void sigchld()
  37 {
  38  int wstat;
  39  int pid;
  40  int i;
  41  while ((pid = wait_nohang(&wstat)) > 0)
  42    for (i = 0;i < auto_spawn;++i) if (d[i].used)
  43      if (d[i].pid == pid)
  44       {
  45        close(d[i].fdout); d[i].fdout = -1;
  46        d[i].wstat = wstat; d[i].pid = 0;
  47       }
  48 }
  49
  50 int flagwriting = 1;
  51
  52 int okwrite(fd,buf,n) int fd; char *buf; int n;
  53 {
  54  int w;
  55  if (!flagwriting) return n;
  56  w = write(fd,buf,n);
  57  if (w != -1) return w;
  58  if (errno == error_intr) return -1;
  59  flagwriting = 0; close(fd);
  60  return n;
  61 }
  62
  63 int flagreading = 1;
  64 char outbuf[1024]; substdio ssout;
  65
  66 int stage = 0; /* reading 0:delnum 1:messid 2:sender 3:recip */
  67 int flagabort = 0; /* if 1, everything except delnum is garbage */
  68 int delnum;
  69 stralloc messid = {0};
  70 stralloc sender = {0};
  71 stralloc recip = {0};
  72
  73 void err(s) char *s;
  74 {
  75  char ch; ch = delnum; substdio_put(&ssout,&ch,1);
  76  substdio_puts(&ssout,s); substdio_putflush(&ssout,"",1);
  77 }
  78
  79 void docmd()
  80 {
  81  int f;
  82  int i;
  83  int j;
  84  int fdmess;
  85  int pi[2];
  86  struct stat st;
  87
  88  if (flagabort) { err("Zqmail-spawn out of memory. (#4.3.0)\n"); return; }
  89  if (delnum < 0) { err("ZInternal error: delnum negative. (#4.3.5)\n"); return; }
  90  if (delnum >= auto_spawn) { err("ZInternal error: delnum too big. (#4.3.5)\n"); return; }
  91  if (d[delnum].used) { err("ZInternal error: delnum in use. (#4.3.5)\n"); return; }
  92  for (i = 0;i < messid.len;++i)
  93    if (messid.s[i])
  94      if (!i || (messid.s[i] != '/'))
  95        if ((unsigned char) (messid.s[i] - '0') > 9)
  96         { err("DInternal error: messid has nonnumerics. (#5.3.5)\n"); return; }
  97  if (messid.len > 100) { err("DInternal error: messid too long. (#5.3.5)\n"); return; }
  98  if (!messid.s[0]) { err("DInternal error: messid too short. (#5.3.5)\n"); return; }
  99
 100  if (!stralloc_copys(&d[delnum].output,""))
 101   { err("Zqmail-spawn out of memory. (#4.3.0)\n"); return; }
 102
 103  j = byte_rchr(recip.s,recip.len,'@');
 104  if (j >= recip.len) { err("DSorry, address must include host name. (#5.1.3)\n"); return; }
 105
 106  fdmess = open_read(messid.s);
 107  if (fdmess == -1) { err("Zqmail-spawn unable to open message. (#4.3.0)\n"); return; }
 108
 109  if (fstat(fdmess,&st) == -1)
 110   { close(fdmess); err("Zqmail-spawn unable to fstat message. (#4.3.0)\n"); return; }
 111  if ((st.st_mode & S_IFMT) != S_IFREG)
 112   { close(fdmess); err("ZSorry, message has wrong type. (#4.3.5)\n"); return; }
 113  if (st.st_uid != auto_uidq) /* aaack! qmailq has to be trusted! */
 114   /* your security is already toast at this point. damage control... */
 115   { close(fdmess); err("ZSorry, message has wrong owner. (#4.3.5)\n"); return; }
 116
 117  if (pipe(pi) == -1)
 118   { close(fdmess); err("Zqmail-spawn unable to create pipe. (#4.3.0)\n"); return; }
 119
 120  coe(pi[0]);
 121
 122  f = spawn(fdmess,pi[1],sender.s,recip.s,j);
 123  close(fdmess);
 124  if (f == -1)
 125   { close(pi[0]); close(pi[1]); err("Zqmail-spawn unable to fork. (#4.3.0)\n"); return; }
 126
 127  d[delnum].fdin = pi[0];
 128  d[delnum].fdout = pi[1]; coe(pi[1]);
 129  d[delnum].pid = f;
 130  d[delnum].used = 1;
 131 }
 132
 133 char cmdbuf[1024];
 134
 135 void getcmd()
 136 {
 137  int i;
 138  int r;
 139  char ch;
 140
 141  r = read(0,cmdbuf,sizeof(cmdbuf));
 142  if (r == 0)
 143   { flagreading = 0; return; }
 144  if (r == -1)
 145   {
 146    if (errno != error_intr)
 147      flagreading = 0;
 148    return;
 149   }
 150
 151  for (i = 0;i < r;++i)
 152   {
 153    ch = cmdbuf[i];
 154    switch(stage)
 155     {
 156      case 0:
 157        delnum = (unsigned int) (unsigned char) ch;
 158        messid.len = 0; stage = 1; break;
 159      case 1:
 160        if (!stralloc_append(&messid,&ch)) flagabort = 1;
 161        if (ch) break;
 162        sender.len = 0; stage = 2; break;
 163      case 2:
 164        if (!stralloc_append(&sender,&ch)) flagabort = 1;
 165        if (ch) break;
 166        recip.len = 0; stage = 3; break;
 167      case 3:
 168        if (!stralloc_append(&recip,&ch)) flagabort = 1;
 169        if (ch) break;
 170        docmd();
 171        flagabort = 0; stage = 0; break;
 172     }
 173   }
 174 }
 175
 176 char inbuf[128];
 177
 178 void main(argc,argv)
 179 int argc;
 180 char **argv;
 181 {
 182  char ch;
 183  int i;
 184  int r;
 185  fd_set rfds;
 186  int nfds;
 187
 188  if (chdir(auto_qmail) == -1) _exit(111);
 189  if (chdir("queue/mess") == -1) _exit(111);
 190  if (!stralloc_copys(&messid,"")) _exit(111);
 191  if (!stralloc_copys(&sender,"")) _exit(111);
 192  if (!stralloc_copys(&recip,"")) _exit(111);
 193
 194  d = (struct delivery *) alloc((auto_spawn + 10) * sizeof(struct delivery));
 195  if (!d) _exit(111);
 196
 197  substdio_fdbuf(&ssout,okwrite,1,outbuf,sizeof(outbuf));
 198
 199  sig_pipeignore();
 200  sig_childcatch(sigchld);
 201
 202  initialize(argc,argv);
 203
 204  ch = auto_spawn; substdio_putflush(&ssout,&ch,1);
 205
 206  for (i = 0;i < auto_spawn;++i) { d[i].used = 0; d[i].output.s = 0; }
 207
 208  for (;;)
 209   {
 210    if (!flagreading)
 211     {
 212      for (i = 0;i < auto_spawn;++i) if (d[i].used) break;
 213      if (i >= auto_spawn) _exit(0);
 214     }
 215    sig_childunblock();
 216
 217    FD_ZERO(&rfds);
 218    if (flagreading) FD_SET(0,&rfds);
 219    nfds = 1;
 220    for (i = 0;i < auto_spawn;++i) if (d[i].used)
 221     { FD_SET(d[i].fdin,&rfds); if (d[i].fdin >= nfds) nfds = d[i].fdin + 1; }
 222
 223    r = select(nfds,&rfds,(fd_set *) 0,(fd_set *) 0,(struct timeval *) 0);
 224    sig_childblock();
 225
 226    if (r != -1)
 227     {
 228      if (flagreading)
 229        if (FD_ISSET(0,&rfds))
 230          getcmd();
 231      for (i = 0;i < auto_spawn;++i) if (d[i].used)
 232        if (FD_ISSET(d[i].fdin,&rfds))
 233         {
 234          r = read(d[i].fdin,inbuf,128);
 235          if (r == -1)
 236            continue; /* read error on a readable pipe? be serious */
 237          if (r == 0)
 238           {
 239            ch = i; substdio_put(&ssout,&ch,1);
 240            report(&ssout,d[i].wstat,d[i].output.s,d[i].output.len);
 241            substdio_put(&ssout,"",1);
 242            substdio_flush(&ssout);
 243            close(d[i].fdin); d[i].used = 0;
 244            continue;
 245           }
 246          while (!stralloc_readyplus(&d[i].output,r)) sleep(10); /*XXX*/
 247          byte_copy(d[i].output.s + d[i].output.len,r,inbuf);
 248          d[i].output.len += r;
 249          if (truncreport > 100)
 250            if (d[i].output.len > truncreport)
 251             {
 252              char *truncmess = "\nError report too long, sorry.\n";
 253              d[i].output.len = truncreport - str_len(truncmess) - 3;
 254              stralloc_cats(&d[i].output,truncmess);
 255             }
 256         }
 257     }
 258   }
 259 }