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#include <sys/types.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <bglibs/str.h>
#include "auth-lib.h"
#include "ucspi-proxy.h"
const char filter_connfail_prefix[] = "* NO ";
const char filter_connfail_suffix[] = "\r\n";
extern const char* local_name;
static str label;
static str saved_label;
static str linebuf;
static int parse_label(void)
{
int end;
if ((end = str_findfirst(&linebuf, ' ')) <= 0) return 0;
str_copyb(&label, linebuf.s, end);
return end + 1;
}
static void handle_login(int offset)
{
const char* start;
const char* end;
start = linebuf.s + offset;
while (isspace(*start))
++start;
if (*start == '"') {
end = ++start;
while (*end != '"')
++end;
}
else {
end = start;
while (!isspace(*end))
++end;
}
make_username(start, end - start, "LOGIN ");
str_splice(&linebuf, start-linebuf.s, end-start, &username);
str_copy(&saved_label, &label);
str_truncate(&label, 0);
}
static void filter_client_line(void)
{
int offset;
const char* cmd;
if (!handle_auth_response(&linebuf, 0)) {
if ((offset = parse_label()) > 0) {
cmd = linebuf.s + offset;
/* If we see a "AUTHENTICATE" or "LOGIN" command, save the preceding
* label for reference when looking for the corresponding "OK" */
if(!strncasecmp(cmd, "AUTHENTICATE ", 13)) {
if (handle_auth_parameter(&linebuf, offset + 13))
str_copy(&saved_label, &label);
}
else if (!strncasecmp(cmd, "LOGIN ", 6))
handle_login(offset + 6);
}
}
}
static void filter_client_data(char* data, ssize_t size)
{
char* lf;
while ((lf = memchr(data, LF, size)) != 0) {
str_catb(&linebuf, data, lf - data + 1);
filter_client_line();
write_server(linebuf.s, linebuf.len);
linebuf.len = 0;
size -= lf - data + 1;
data = lf + 1;
}
str_catb(&linebuf, data, size);
}
static void filter_server_data(char* data, ssize_t size)
{
if(saved_label.len > 0) {
/* Skip continuation data */
if(data[0] != '+') {
int resp;
/* Check if the response is tagged with the saved label */
str_copyb(&linebuf, data, size);
resp = parse_label();
if(resp > 0) {
if(!str_diff(&label, &saved_label)) {
log_line(data, size);
/* Check if the response was an OK */
if(!strncasecmp(linebuf.s + resp, "OK ", 3))
accept_client(username.s);
else
deny_client(username.s);
str_truncate(&saved_label, 0);
}
}
}
}
write_client(data, size);
}
void imap_filter_init(void)
{
set_filter(CLIENT_IN, filter_client_data, 0);
set_filter(SERVER_FD, filter_server_data, 0);
}
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