summaryrefslogtreecommitdiff
path: root/qmail-popup.c
blob: a18b73ed220668ac408f15dc67b166779a1bf13e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
#include "commands.h"
#include "fd.h"
#include "sig.h"
#include "stralloc.h"
#include "substdio.h"
#include "alloc.h"
#include "wait.h"
#include "str.h"
#include "byte.h"
#include "now.h"
#include "fmt.h"
#include "exit.h"
#include "readwrite.h"
#include "timeoutread.h"
#include "timeoutwrite.h"

void die() { _exit(1); }

int saferead(fd,buf,len) int fd; char *buf; int len;
{
  int r;
  r = timeoutread(1200,fd,buf,len);
  if (r <= 0) die();
  return r;
}

int safewrite(fd,buf,len) int fd; char *buf; int len;
{
  int r;
  r = timeoutwrite(1200,fd,buf,len);
  if (r <= 0) die();
  return r;
}

char ssoutbuf[128];
substdio ssout = SUBSTDIO_FDBUF(safewrite,1,ssoutbuf,sizeof ssoutbuf);

char ssinbuf[128];
substdio ssin = SUBSTDIO_FDBUF(saferead,0,ssinbuf,sizeof ssinbuf);

void myputs(s) char *s;
{
  substdio_puts(&ssout,s);
}
void flush()
{
  substdio_flush(&ssout);
}
void err(s) char *s;
{
  myputs("-ERR ");
  myputs(s);
  myputs("\r\n");
  flush();
}

void die_usage() { err("usage: popup hostname subprogram"); die(); }
void die_nomem() { err("out of memory"); die(); }
void die_pipe() { err("unable to open pipe"); die(); }
void die_write() { err("unable to write pipe"); die(); }
void die_fork() { err("unable to fork"); die(); }
void die_childcrashed() { err("aack, child crashed"); }
void die_badauth() { err("authorization failed"); }

void err_syntax() { err("syntax error"); }
void err_wantuser() { err("USER first"); }
void err_authoriz(arg) char *arg; { err("authorization first"); }

void okay(arg) char *arg; { myputs("+OK \r\n"); flush(); }
void pop3_quit(arg) char *arg; { okay(0); die(); }


char unique[FMT_ULONG + FMT_ULONG + 3];
char *hostname;
stralloc username = {0};
int seenuser = 0;
char **childargs;
substdio ssup;
char upbuf[128];


void doanddie(user,userlen,pass)
char *user;
unsigned int userlen; /* including 0 byte */
char *pass;
{
  int child;
  int wstat;
  int pi[2];
 
  if (fd_copy(2,1) == -1) die_pipe();
  close(3);
  if (pipe(pi) == -1) die_pipe();
  if (pi[0] != 3) die_pipe();
  switch(child = fork()) {
    case -1:
      die_fork();
    case 0:
      close(pi[1]);
      sig_pipedefault();
      execvp(*childargs,childargs);
      _exit(1);
  }
  close(pi[0]);
  substdio_fdbuf(&ssup,write,pi[1],upbuf,sizeof upbuf);
  if (substdio_put(&ssup,user,userlen) == -1) die_write();
  if (substdio_put(&ssup,pass,str_len(pass) + 1) == -1) die_write();
  if (substdio_puts(&ssup,"<") == -1) die_write();
  if (substdio_puts(&ssup,unique) == -1) die_write();
  if (substdio_puts(&ssup,hostname) == -1) die_write();
  if (substdio_put(&ssup,">",2) == -1) die_write();
  if (substdio_flush(&ssup) == -1) die_write();
  close(pi[1]);
  byte_zero(pass,str_len(pass));
  byte_zero(upbuf,sizeof upbuf);
  if (wait_pid(&wstat,child) == -1) die();
  if (wait_crashed(wstat)) die_childcrashed();
  if (wait_exitcode(wstat)) die_badauth();
  die();
}
void pop3_greet()
{
  char *s;
  s = unique;
  s += fmt_uint(s,getpid());
  *s++ = '.';
  s += fmt_ulong(s,(unsigned long) now());
  *s++ = '@';
  *s++ = 0;
  myputs("+OK <");
  myputs(unique);
  myputs(hostname);
  myputs(">\r\n");
  flush();
}
void pop3_user(arg) char *arg;
{
  if (!*arg) { err_syntax(); return; }
  okay(0);
  seenuser = 1;
  if (!stralloc_copys(&username,arg)) die_nomem(); 
  if (!stralloc_0(&username)) die_nomem(); 
}
void pop3_pass(arg) char *arg;
{
  if (!seenuser) { err_wantuser(); return; }
  if (!*arg) { err_syntax(); return; }
  doanddie(username.s,username.len,arg);
}
void pop3_apop(arg) char *arg;
{
  char *space;
  space = arg + str_chr(arg,' ');
  if (!*space) { err_syntax(); return; }
  *space++ = 0;
  doanddie(arg,space - arg,space);
}

struct commands pop3commands[] = {
  { "user", pop3_user, 0 }
, { "pass", pop3_pass, 0 }
, { "apop", pop3_apop, 0 }
, { "quit", pop3_quit, 0 }
, { "noop", okay, 0 }
, { 0, err_authoriz, 0 }
} ;

void main(argc,argv)
int argc;
char **argv;
{
  sig_alarmcatch(die);
  sig_pipeignore();
 
  hostname = argv[1];
  if (!hostname) die_usage();
  childargs = argv + 2;
  if (!*childargs) die_usage();
 
  pop3_greet();
  commands(&ssin,pop3commands);
  die();
}