/**
* An attempt at an IMAP4 server. I don't know if I'll actually get it working
* but I thought it might be fun to try.
*
* @author Ceres
* @date 26 August 2000
*/
#include <network.h>
#include <mail.h>
#include <imap4.h>
#include <mime.h>
inherit SERVER;
private void parse_comm(class imap_session sess, string str);
private string *imap_states = ({
"CONNECTED",
"AUTHENTICATED",
"SELECTED"
});
private mapping Sockets;
private nosave mapping cache;
private nosave int reads, hits;
private mapping last;
protected void create() {
server::create();
SetSocketType(STREAM);
SetDestructOnClose(1);
Sockets = ([]);
call_out("setup", 2);
call_out("clean_sockets", 180);
unguarded((: restore_object, "/net/save/imap4" :));
if(!last)
last = ([ ]);
} /* create() */
/** @ignore yes */
protected void setup() {
if (eventCreateSocket(PORT_IMAP4) < 0) {
if (this_object()) {
destruct(this_object());
}
}
} /* setup() */
/** @ignore yes */
protected void eventNewConnection(int fd) {
class imap_session sess;
server::eventNewConnection(fd);
sess = new(class imap_session, fd : fd, state : IMAP_CONNECTED, command : "",
deleted : ({}), messages : ({}));
Sockets[fd] = sess;
eventWrite(fd, sprintf("* OK IMAP4 %s Discworld v%s server ready\r\n",
query_host_name(), IMAP4_VERSION));
} /* eventNewConnection() */
/** @ignore yes */
protected void eventRead(int fd, string str) {
string *bits, bit;
class imap_session sess = Sockets[fd];
if (!sess) {
return;
}
if (str) {
sess->command += str;
if (strsrch(str, '\n') == -1) {
return;
}
}
sess->command = replace_string(sess->command, "\r", "");
bits = explode(sess->command, "\n");
if (!sizeof(bits)) {
eventWrite(fd, "-ERR Null command\r\n");
} else {
foreach (bit in bits) {
parse_comm(sess, bit);
}
}
sess->command = "";
}
/** @ignore yes */
protected void eventSocketClosed(int fd) {
class imap_session sess = Sockets[fd];
if (!sess) {
return;
}
map_delete(Sockets, fd);
} /* eventSocketClosed() */
private void sign_off(class imap_session sess) {
int *deleted;
if (sizeof(sess->deleted)) {
deleted = map(sess->deleted, (: $2->headers[$1-1]->number :), sess);
FOLDER_H->delete_it(sess->user_name, "inbox", deleted);
}
unguarded((: save_object, "/net/save/imap4" :));
} /* sign_off() */
private void load_message(class imap_session sess, int message) {
string mess;
int which;
reads++;
which = sess->headers[message]->number;
if(!cache)
cache = ([ ]);
if(cache[which]) {
hits++;
sess->messages[message] = cache[which];
return;
}
mess = FOLDER_H->load_message(sess->user_name, "inbox",
sess->headers[message]->number);
mess = MIME->rewrite_header(mess);
mess = replace_string(mess, "\n", "\r\n");
if (mess[<1] != '\n') {
mess += "\r\n";
}
sess->messages[message] = mess;
sess->sizes[message] = strlen(mess);
cache[which] = copy(mess);
} /* load_message() */
private void load_folder(class imap_session sess) {
int *tmp, max, i;
sess->headers = FOLDER_H->get_messages(sess->user_name, sess->selected);
tell_creator("ceres", "Headers: %d\n", sizeof(sess->headers));
sess->messages = allocate(sizeof(sess->headers));
sess->sizes = allocate(sizeof(sess->headers));
sess->num_messages = sizeof(sess->headers);
// the sizes will start out as an approximation. As we read actual messages
// the real size will be put in place.
tmp = sess->sizes;
for(i=0; i<sizeof(sess->headers); i++)
sess->sizes[i] = 1000;
// If we'd already got some sizes then copy them into the new size array.
if(tmp) {
(sizeof(tmp) > sizeof(sess->headers)) ? max = sizeof(tmp) :
max = sizeof(sess->headers);
for(i=0; i<max; i++)
sess->sizes[i] = tmp[i];
}
} /* load_folder() */
private void parse_comm(class imap_session sess, string str) {
string *bits, rest, cmd, tmp;
int fd = sess->fd, i, j, k;
string id;
TP("Parsing " + str + ".\n");
bits = explode(str, " ");
id = bits[0];
cmd = bits[1];
sess->time = time();
switch(lower_case(cmd)) {
case "capability":
eventWrite(fd, "* CAPABILITY IMAP4 IMAP4rev1 NAMESPACE AUTH=LOGIN\r\n");
eventWrite(fd, sprintf("%s OK CAPABILITY completed.\r\n",
id, sess->num_messages));
TP("Sent capability\n");
break;
case "noop":
eventWrite(fd, id + " OK NOOP completed\r\n");
break;
case "logout":
sign_off(sess);
eventWrite(fd, id + " OK LOGOUT completed\r\n", 1);
break;
case "authenticate":
CHECK_STATE(IMAP_CONNECTED);
eventWrite(fd, sprintf("%s NO - unsupported authentication mechanism.\r\n",
id, sess->num_messages));
break;
case "login":
CHECK_STATE(IMAP_CONNECTED);
if (sizeof(bits) > 4 ) {
rest = implode(bits[3..], " ");
} else if(sizeof(bits) > 3) {
rest = bits[3];
}
CHECK_CMD(2, id + " BAD - missing arguments\r\n");
bits[2] = replace(bits[2], "\"", "");
rest = replace(rest, "\"", "");
if (!LOGIN_OB->test_password(bits[2], rest)) {
sess->state = IMAP_CONNECTED;
eventWrite(fd, id + " NO - login failure: user name or password rejected\r\n");
} else {
sess->state = IMAP_AUTHENTICATED;
sess->user_name = bits[2];
TP(bits[2] + " logged in.\n");
eventWrite(fd, sprintf("%s OK LOGIN completed\r\n",
id, sess->num_messages));
}
break;
case "select":
CHECK_STATE(IMAP_AUTHENTICATED);
CHECK_CMD(1, id + " BAD - missing argument.\r\n");
sess->selected = replace(bits[2], ({"\"", "", "/", ""}));
sess->state = IMAP_SELECTED;
eventWrite(fd, id + " OK - SELECT completed\r\n");
break;
case "examine":
case "create":
case "delete":
case "rename":
case "subscribe":
case "unsubscribe":
case "list":
CHECK_STATE(IMAP_AUTHENTICATED);
foreach(tmp in MAILER->query_folders(sess->user_name)) {
eventWrite(fd, "* LIST (\\Noselect) \"/\" /" + tmp + "\r\n");
}
eventWrite(fd, id + " OK LIST completed\r\n");
break;
case "lsub":
CHECK_STATE(IMAP_AUTHENTICATED);
foreach(tmp in MAILER->query_folders(sess->user_name)) {
eventWrite(fd, "* LSUB () \"/\" /" + tmp + "\r\n");
}
eventWrite(fd, id + " OK LSUB completed\r\n");
break;
case "status":
case "append":
case "uid":
CHECK_STATE(IMAP_SELECTED);
CHECK_CMD(1, id + " BAD - missing argument.\r\n");
switch(lower_case(bits[2])) {
case "fetch":
TP("Doing fetch\n");
load_folder(sess);
if(sscanf(bits[3], "%d:%d", j, k) != 2) {
sscanf(bits[3], "%d:*", j);
k = sess->num_messages;
}
for(i=j; i<k; i++) {
eventWrite(fd, " * " + i + " FETCH (FLAGS (\\Seen) UID " +
sess->headers[i]->number + "\r\n");
}
eventWrite(fd, id + " UID FETCH completed\r\n");
TP("Ok, done\n");
break;
case "copy":
case "store":
}
break;
default:
eventWrite(fd, sprintf("-ERR Unknown command in %s state\r\n",
imap_states[sess->state]));
break;
}
TP("done parsing\n");
} /* parse_comm() */
/** @ignore yes */
protected void close_connection(class imap_session sess) {
if (!sess) {
return;
}
eventWrite(sess->fd, "-ERR Autologout; idle for too long\r\n", 1);
} /* close_connection() */
/** @ignore yes */
protected void clean_sockets() {
class imap_session sess;
foreach (sess in values(Sockets)) {
if (!sess->time) {
sess->time = time();
continue;
}
if (time() - sess->time > 1800)
close_connection(sess);
}
call_out("clean_sockets", 180);
} /* clean_sockets() */
mixed *stats() {
if(!cache)
cache = ([ ]);
return ({
({ "reads", reads, }),
({ "cache hit percent", reads != 0 ? (hits * 100) / reads : 0, }),
({ "messages in cache", sizeof(keys(cache)), }),
});
}
