#include <unistd.h>

#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(void) { _exit(1); }

int saferead(int fd, void *buf, int len)

{

int r;

r = timeoutread(1200,fd,buf,len);

if (r <= 0) die();

return r;

}

int safewrite(int fd, void *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 putstr(const char *s)

{

substdio_puts(&ssout,s);

}

void flush(void)

{

substdio_flush(&ssout);

}

void err(const char *s)

{

putstr("-ERR ");

putstr(s);

putstr("\r\n");

flush();

}

void die_usage(void) { err("usage: popup hostname subprogram"); die(); }

void die_nomem(void) { err("out of memory"); die(); }

void die_pipe(void) { err("unable to open pipe"); die(); }

void die_write(void) { err("unable to write pipe"); die(); }

void die_fork(void) { err("unable to fork"); die(); }

void die_childcrashed(void) { err("aack, child crashed"); }

void die_badauth(void) { err("authorization failed"); }

/* checkpassword error exit codes:

* 1 = error in server configuration

* 2 = unable to contact authorization server

* 25= user record incorrect

* 3 = authorization failed

* 4 = account disabled

* 5 = mailhost is unreachable

* 6 = mailbox is corrupted

* 61= mailbox creation failed

* 62= the users mailbox does not exist

* 7 = unable to start subprogram

* 8 = out of memory

*/

void die_1(void) { err("error in server configuration"); die(); }

void die_2(void) { err("unable to contact authorization server"); die(); }

void die_25(void) { err("user record incorrect"); die(); }

void die_3(void) { err("authorization failed"); die(); }

void die_4(void) { err("account disabled"); die(); }

void die_5(void) { err("mailhost is unreachable"); die(); }

void die_6(void) { err("mailbox is corrupted"); die(); }

void die_61(void) { err("mailbox could not be created"); die(); }

void die_62(void) { err("the users mailbox does not exist"); die(); }

void die_7(void) { err("unable to start subprogram"); die(); }

void die_unknown(void) { err("temporary error"); die(); }

void err_syntax(void) { err("syntax error"); }

void err_wantuser(void) { err("USER first"); }

void err_authoriz(void) { err("authorization first"); }

void okay(void) { putstr("+OK \r\n"); flush(); }

void pop3_quit(void) { okay(); 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(char *user, unsigned int userlen /* including 0 byte */,

char *pass)

{

int child;

int wstat;

int pi[2];

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,subwrite,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();

switch (wait_exitcode(wstat)) {

case 0: die();

case 1: die_1();

case 2: die_2();

case 25: die_25();

case 3: die_3();

case 4: die_4();

case 5: die_5();

case 6: die_6();

case 61: die_61();

case 62: die_62();

case 7: die_7();

case 8: die_nomem();

default: die_unknown();

}

die();

}

void pop3_greet(void)

{

char *s;

s = unique;

s += fmt_uint(s,getpid());

*s++ = '.';

s += fmt_ulong(s,(unsigned long) now());

*s++ = '@';

*s++ = 0;

putstr("+OK <");

putstr(unique);

putstr(hostname);

putstr(">\r\n");

flush();

}

void pop3_user(char *arg)

{

if (!*arg) { err_syntax(); return; }

okay();

seenuser = 1;

if (!stralloc_copys(&username,arg)) die_nomem();

if (!stralloc_0(&username)) die_nomem();

}

void pop3_pass(char *arg)

{

if (!seenuser) { err_wantuser(); return; }

if (!*arg) { err_syntax(); return; }

doanddie(username.s,username.len,arg);

}

void pop3_apop(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 }

} ;

int main(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);

return 1;

}