Merge branches 'idx/verh' and 'idx/qmqpc'

[qmail] / addrcheck.c

#include "cdb.h"
#include "stralloc.h"
#include "byte.h"
#include "str.h"
#include "addrcheck.h"
#include <errno.h>
#include <unistd.h>

/* #define DEBUG */
#ifdef DEBUG
#  define D(x) x
#  include <stdio.h>
#  include <sys/types.h>
#else
#  define D(x)
#endif

#define STRALLOC_INIT { 0 }

static int probe(int cdb, int prefix, const char *key, int len,
		 const char *suffix, const char **kp, uint32 *dlen)
{
  static stralloc k = STRALLOC_INIT;
  char ch = prefix;
  int rc;

  k.len = 0;
  if (!stralloc_append(&k, &ch) ||
      !stralloc_catb(&k, key, len) ||
      (suffix && !stralloc_cats(&k, suffix)) ||
      !stralloc_0(&k))
    return (-1);
  if (kp) *kp = k.s;
  D( fprintf(stderr, "*** `%.*s' -> ", k.len, k.s); )
  rc = cdb_seek(cdb, k.s, k.len - 1, dlen);
  D( if (rc == -1)
       fprintf(stderr, "error: %s\n", strerror(errno));
     else if (rc == 0)
       fprintf(stderr, "not found\n");
     else if (!*dlen)
       fprintf(stderr, "empty\n");
     else {
       int n = *dlen;
       int nn;
       char buf[256];
       off_t pos = lseek(cdb, 0, SEEK_CUR);
       fprintf(stderr, "`");
       while (n) {
	 nn = sizeof(buf); if (nn > n) nn = n;
	 read(cdb, buf, nn);
	 fwrite(buf, 1, nn, stderr);
	 n -= nn;
       }
       fprintf(stderr, "'\n");
       lseek(cdb, pos, SEEK_SET);
     } )
  return (rc);
}

static int localprobe(int cdb, const char *sender,
		      const char *key, int len,
		      const char *suffix, const char *tail, int *rc)
{
  int err;
  uint32 dlen;
  char ch;
  const char *k;
  static stralloc u =  STRALLOC_INIT;
  static stralloc serv = STRALLOC_INIT;
  int kid;
  int n;
  int wstat;
  int p[2];

  if ((err = probe(cdb, 'L', key, len, suffix, &k, &dlen)) < 0)
    return (-1);
  if (!err) { *rc = 0; return (0); }
  if (!dlen) { errno = EINVAL; return (-1); }  
  if (read(cdb, &ch, 1) != 1) { errno = EIO; return (-1); }
  if (ch == '?') {
    u.len = 0;
    if (!stralloc_ready(&u, dlen - 1)) return (-1);
    if (read(cdb, u.s, dlen - 1) != dlen - 1) { errno = EIO; return (-1); }
    u.len = dlen - 1;
    serv.len = 0;
    if (!stralloc_cats(&serv, "addrcheck:") ||
	!stralloc_cats(&serv, k + 1) ||
	!stralloc_0(&serv) ||
	!stralloc_0(&u))
      return (-1);
    D( fprintf(stderr, "asking user:\n\
  user = %s; service = %s\n  tail = %s; sender = %s\n\
  address = %s; key = %s\n",
	       u.s, serv.s, tail, sender, key, k + 1); )
	       
    if (pipe(p) || (kid = fork()) == -1)
      return (-1);
    if (!kid) {
      dup2(p[1], 1);
      close(p[0]);
      close(p[1]);
      execl("/usr/bin/userv", "/usr/bin/userv",
	    "-f", "stdin=/dev/null",
	    u.s, serv.s,
	    tail, sender, key, k + 1,
	    (char *)0);
      _exit(127);
    }
    close(p[1]);
    n = read(p[0], &ch, 1);
    close(p[0]);
    if (wait_pid(&wstat, kid) < 0) { return (-1); }
    D( fprintf(stderr, "userv exited with status %d\n", wstat); )
    if (n != 1 || wstat) { errno = EAGAIN; return (-1); }
    D( fprintf(stderr, "userv answer was `%c'\n", ch); )
  } else if (dlen != 1) {
    errno = EIO;
    return (-1);
  }
  *rc = ch;
  return (1);
}

static int local(int cdb, const char *l, int len,
		 const char *sender, int *rc)
{
  int code;
  int err = 0;
  int dash;

  if ((err = localprobe(cdb, sender, l, len, 0, l + len, &code)) != 0)
    goto done;

  for (;;) {
    dash = byte_rchr(l, len, '-');
    if (dash == len) break;
    if ((err = localprobe(cdb, sender,
			  l, dash, "-default", l + dash + 1, &code)) != 0)
      goto done;
    len = dash;
  }
  *rc = 0;
  return (0);
  
done:
  if (err >= 0) {
    switch (code) {
      case '+': *rc = 1; break;
      case '-': *rc = 0; break;
      default: errno = EINVAL; err = -1; break;
    }
  }
  return (err);
}

static int virt(int cdb, const char *u, int ulen,
		const char *addr, int alen, const char *sender, int *rc)
{
  static stralloc l = STRALLOC_INIT;
  uint32 dlen;
  int err;

  if ((err = probe(cdb, 'V', addr, alen, 0, 0, &dlen)) <= 0)
    return (err);
  if (!stralloc_ready(&l, dlen + 1)) return (-1);
  if (read(cdb, l.s, dlen) != dlen) { errno = EIO; return (-1); }
  l.s[dlen] = '-';
  l.len = dlen + 1;
  if (!stralloc_catb(&l, u, ulen) || !stralloc_0(&l)) return (-1);
  D( printf("*** virtual map -> `%s'\n", l.s); )
  if (local(cdb, l.s, l.len - 1, sender, rc) < 0) return (-1);
  return (1);
}

int addrcheck(int cdb, const char *addr, const char *sender, int *rc)
{
  int at, len, dot;
  int err = 0;
  uint32 dlen;

  len = str_len(addr);
  at = str_chr(addr, '@');
  if (!addr[at])
    return (local(cdb, addr, len, sender, rc));

  if ((err = virt(cdb, addr, at, addr, len, sender, rc)) != 0)
    return (err);
  dot = at + 1;
  while (addr[dot]) {
    if ((err = virt(cdb, addr, at, addr + dot, len - dot, sender, rc)) != 0)
      return (err);
    dot += byte_chr(addr + dot + 1, len - dot - 1, '.') + 1;
  }

  if ((err = probe(cdb, '@', addr + at + 1, len - at - 1, 0, 0, &dlen)) < 0)
    return (-1);
  if (!err) { *rc = 1; return (0); }
  if (dlen != 0) { errno = EINVAL; return (-1); }

  return (local(cdb, addr, at, sender, rc));
}

#ifdef TEST

#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <unistd.h>

int main(int argc, char *argv[])
{
  int fd;
  int rc;
  int i;

  if (argc < 4) {
    fprintf(stderr, "usage: addrcheck CDB SENDER ADDR...\n");
    return (1);
  }
  if ((fd = open(argv[1], O_RDONLY)) < 0) {
    perror(argv[1]);
    return (1);
  }
  for (i = 3; i < argc; i++) {
    if (addrcheck(fd, argv[i], argv[2], &rc) < 0) {
      perror("checking");
      return (1);
    }
    printf("%s: %s\n", argv[i], rc ? "ok" : "bad");
  }
  return (0);
}

#endif