1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) Wolfgang Breyha 2005-2012
6 * Vienna University Computer Center
8 * See the file NOTICE for conditions of use and distribution.
11 /* This patch is based on code from Tom Kistners exiscan (ACL integration) and
12 * the DCC local_scan patch from Christopher Bodenstein */
14 /* Code for calling dccifd. Called from acl.c. */
17 #ifdef EXPERIMENTAL_DCC
21 uschar dcc_header_str
[256];
25 /* This function takes a file descriptor and a buffer as input and
26 * returns either 0 for success or errno in case of error. */
28 int flushbuffer (int socket
, uschar
*buffer
)
31 rsp
= write(socket
, buffer
, Ustrlen(buffer
));
33 debug_printf("DCC: Result of the write() = %d\n", rsp
);
37 debug_printf("DCC: Error writing buffer to socket: %s\n", strerror(errno
));
41 debug_printf("DCC: Wrote buffer to socket:\n%s\n", buffer
);
47 int dcc_process(uschar
**listptr
) {
49 uschar
*list
= *listptr
;
51 uschar
*dcc_daemon_ip
= US
"";
52 uschar
*dcc_default_ip_option
= US
"127.0.0.1";
53 uschar
*dcc_ip_option
= US
"";
54 uschar
*dcc_helo_option
= US
"localhost";
55 uschar
*dcc_reject_message
= US
"Rejected by DCC";
56 uschar
*xtra_hdrs
= NULL
;
59 int i
, j
, k
, c
, retval
, sockfd
, resp
, line
;
61 struct sockaddr_un serv_addr
;
62 struct sockaddr_in serv_addr_in
;
63 struct hostent
*ipaddress
;
65 uschar sockip
[40], client_ip
[40];
67 uschar rcpt
[128], from
[128];
70 uschar dcc_return_text
[1024];
71 uschar mbox_path
[1024];
72 uschar message_subdir
[2];
73 struct header_line
*dcchdr
;
74 uschar
*dcc_acl_options
;
75 uschar dcc_acl_options_buffer
[10];
76 uschar dcc_xtra_hdrs
[1024];
79 if ((dcc_acl_options
= string_nextinlist(&list
, &sep
,
80 dcc_acl_options_buffer
,
81 sizeof(dcc_acl_options_buffer
))) != NULL
)
83 /* parse 1st option */
84 if ( (strcmpic(dcc_acl_options
,US
"false") == 0) ||
85 (Ustrcmp(dcc_acl_options
,"0") == 0) ) {
86 /* explicitly no matching */
90 /* special cases (match anything except empty) */
91 if ( (strcmpic(dcc_acl_options
,US
"true") == 0) ||
92 (Ustrcmp(dcc_acl_options
,"*") == 0) ||
93 (Ustrcmp(dcc_acl_options
,"1") == 0) ) {
94 dcc_acl_options
= dcc_acl_options
;
98 /* empty means "don't match anything" */
104 /* if we scanned this message last time, just return */
108 /* open the spooled body */
109 message_subdir
[1] = '\0';
110 for (i
= 0; i
< 2; i
++) {
111 message_subdir
[0] = (split_spool_directory
== (i
== 0))? message_id
[5] : 0;
112 sprintf(CS mbox_path
, "%s/input/%s/%s-D", spool_directory
, message_subdir
, message_id
);
113 data_file
= Ufopen(mbox_path
,"rb");
114 if (data_file
!= NULL
)
118 if (data_file
== NULL
) {
119 /* error while spooling */
120 log_write(0, LOG_MAIN
|LOG_PANIC
,
121 "dcc acl condition: error while opening spool file");
125 /* Initialize the variables */
127 bzero(sockip
,sizeof(sockip
));
128 if (dccifd_address
) {
129 if (dccifd_address
[0] == '/')
130 Ustrncpy(sockpath
, dccifd_address
, sizeof(sockpath
));
132 if( sscanf(CS dccifd_address
, "%s %u", sockip
, &portnr
) != 2) {
133 log_write(0, LOG_MAIN
,
134 "dcc acl condition: warning - invalid dccifd address: '%s'", dccifd_address
);
135 (void)fclose(data_file
);
140 /* opts is what we send as dccifd options - see man dccifd */
141 /* We don't support any other option than 'header' so just copy that */
142 bzero(opts
,sizeof(opts
));
143 Ustrncpy(opts
, "header", sizeof(opts
)-1);
144 Ustrncpy(client_ip
, dcc_ip_option
, sizeof(client_ip
)-1);
145 /* If the dcc_client_ip is not provided use the
146 * sender_host_address or 127.0.0.1 if it is NULL */
148 debug_printf("DCC: my_ip_option = %s - client_ip = %s - sender_host_address = %s\n", dcc_ip_option
, client_ip
, sender_host_address
);
149 if(!(Ustrcmp(client_ip
, ""))){
150 /* Do we have a sender_host_address or is it NULL? */
151 if(sender_host_address
){
152 Ustrncpy(client_ip
, sender_host_address
, sizeof(client_ip
)-1);
154 /* sender_host_address is NULL which means it comes from localhost */
155 Ustrncpy(client_ip
, dcc_default_ip_option
, sizeof(client_ip
)-1);
159 debug_printf("DCC: Client IP: %s\n", client_ip
);
160 Ustrncpy(sockip
, dcc_daemon_ip
, sizeof(sockip
)-1);
161 /* strncat(opts, my_request, strlen(my_request)); */
163 Ustrncat(opts
, client_ip
, sizeof(opts
)-Ustrlen(opts
)-1);
164 Ustrncat(opts
, "\nHELO ", sizeof(opts
)-Ustrlen(opts
)-1);
165 Ustrncat(opts
, dcc_helo_option
, sizeof(opts
)-Ustrlen(opts
)-2);
168 /* initialize the other variables */
169 dcchdr
= header_list
;
170 /* we set the default return value to DEFER */
173 bzero(sendbuf
,sizeof(sendbuf
));
174 bzero(dcc_header_str
,sizeof(dcc_header_str
));
175 bzero(rcpt
,sizeof(rcpt
));
176 bzero(from
,sizeof(from
));
178 /* send a null return path as "<>". */
179 if (Ustrlen(sender_address
) > 0)
180 Ustrncpy(from
, sender_address
, sizeof(from
));
182 Ustrncpy(from
, "<>", sizeof(from
));
183 Ustrncat(from
, "\n", sizeof(from
)-Ustrlen(from
)-1);
185 /**************************************
186 * Now creating the socket connection *
187 **************************************/
189 /* If there is a dcc_daemon_ip, we use a tcp socket, otherwise a UNIX socket */
190 if(Ustrcmp(sockip
, "")){
191 ipaddress
= gethostbyname((char *)sockip
);
192 bzero((char *) &serv_addr_in
, sizeof(serv_addr_in
));
193 serv_addr_in
.sin_family
= AF_INET
;
194 bcopy((char *)ipaddress
->h_addr
, (char *)&serv_addr_in
.sin_addr
.s_addr
, ipaddress
->h_length
);
195 serv_addr_in
.sin_port
= htons(portnr
);
196 if ((sockfd
= socket(AF_INET
, SOCK_STREAM
,0)) < 0){
198 debug_printf("DCC: Creating TCP socket connection failed: %s\n", strerror(errno
));
199 log_write(0,LOG_PANIC
,"DCC: Creating TCP socket connection failed: %s\n", strerror(errno
));
200 /* if we cannot create the socket, defer the mail */
201 (void)fclose(data_file
);
204 /* Now connecting the socket (INET) */
205 if (connect(sockfd
, (struct sockaddr
*)&serv_addr_in
, sizeof(serv_addr_in
)) < 0){
207 debug_printf("DCC: Connecting to TCP socket failed: %s\n", strerror(errno
));
208 log_write(0,LOG_PANIC
,"DCC: Connecting to TCP socket failed: %s\n", strerror(errno
));
209 /* if we cannot contact the socket, defer the mail */
210 (void)fclose(data_file
);
214 /* connecting to the dccifd UNIX socket */
215 bzero((char *)&serv_addr
,sizeof(serv_addr
));
216 serv_addr
.sun_family
= AF_UNIX
;
217 Ustrcpy(serv_addr
.sun_path
, sockpath
);
218 if ((sockfd
= socket(AF_UNIX
, SOCK_STREAM
,0)) < 0){
220 debug_printf("DCC: Creating UNIX socket connection failed: %s\n", strerror(errno
));
221 log_write(0,LOG_PANIC
,"DCC: Creating UNIX socket connection failed: %s\n", strerror(errno
));
222 /* if we cannot create the socket, defer the mail */
223 (void)fclose(data_file
);
226 /* Now connecting the socket (UNIX) */
227 if (connect(sockfd
, (struct sockaddr
*) &serv_addr
, sizeof(serv_addr
)) < 0){
229 debug_printf("DCC: Connecting to UNIX socket failed: %s\n", strerror(errno
));
230 log_write(0,LOG_PANIC
,"DCC: Connecting to UNIX socket failed: %s\n", strerror(errno
));
231 /* if we cannot contact the socket, defer the mail */
232 (void)fclose(data_file
);
236 /* the socket is open, now send the options to dccifd*/
238 debug_printf("\nDCC: ---------------------------\nDCC: Socket opened; now sending input\nDCC: -----------------\n");
239 /* First, fill in the input buffer */
240 Ustrncpy(sendbuf
, opts
, sizeof(sendbuf
));
241 Ustrncat(sendbuf
, from
, sizeof(sendbuf
)-Ustrlen(sendbuf
)-1);
245 debug_printf("DCC: opts = %s\nDCC: sender = %s\nDCC: rcpt count = %d\n", opts
, from
, recipients_count
);
246 debug_printf("DCC: Sending options:\nDCC: ****************************\n");
249 /* let's send each of the recipients to dccifd */
250 for (i
= 0; i
< recipients_count
; i
++){
252 debug_printf("DCC: recipient = %s\n",recipients_list
[i
].address
);
253 if(Ustrlen(sendbuf
) + Ustrlen(recipients_list
[i
].address
) > sizeof(sendbuf
))
256 debug_printf("DCC: Writing buffer: %s\n", sendbuf
);
257 flushbuffer(sockfd
, sendbuf
);
258 bzero(sendbuf
, sizeof(sendbuf
));
260 Ustrncat(sendbuf
, recipients_list
[i
].address
, sizeof(sendbuf
)-Ustrlen(sendbuf
)-1);
261 Ustrncat(sendbuf
, "\r\n", sizeof(sendbuf
)-Ustrlen(sendbuf
)-1);
263 /* send a blank line between options and message */
264 Ustrncat(sendbuf
, "\n", sizeof(sendbuf
)-Ustrlen(sendbuf
)-1);
265 /* Now we send the input buffer */
267 debug_printf("DCC: %s\nDCC: ****************************\n", sendbuf
);
268 flushbuffer(sockfd
, sendbuf
);
270 /* now send the message */
271 /* Clear the input buffer */
272 bzero(sendbuf
, sizeof(sendbuf
));
273 /* First send the headers */
274 /* Now send the headers */
276 debug_printf("DCC: Sending headers:\nDCC: ****************************\n");
277 Ustrncpy(sendbuf
, dcchdr
->text
, sizeof(sendbuf
)-2);
278 while((dcchdr
=dcchdr
->next
)) {
279 if(dcchdr
->slen
> sizeof(sendbuf
)-2) {
280 /* The size of the header is bigger than the size of
281 * the input buffer, so split it up in smaller parts. */
282 flushbuffer(sockfd
, sendbuf
);
283 bzero(sendbuf
, sizeof(sendbuf
));
285 while(j
< dcchdr
->slen
)
287 for(i
= 0; i
< sizeof(sendbuf
)-2; i
++) {
288 sendbuf
[i
] = dcchdr
->text
[j
];
291 flushbuffer(sockfd
, sendbuf
);
292 bzero(sendbuf
, sizeof(sendbuf
));
294 } else if(Ustrlen(sendbuf
) + dcchdr
->slen
> sizeof(sendbuf
)-2) {
295 flushbuffer(sockfd
, sendbuf
);
296 bzero(sendbuf
, sizeof(sendbuf
));
297 Ustrncpy(sendbuf
, dcchdr
->text
, sizeof(sendbuf
)-2);
299 Ustrncat(sendbuf
, dcchdr
->text
, sizeof(sendbuf
)-Ustrlen(sendbuf
)-2);
303 /* a blank line seperates header from body */
304 Ustrncat(sendbuf
, "\n", sizeof(sendbuf
)-Ustrlen(sendbuf
)-1);
305 flushbuffer(sockfd
, sendbuf
);
307 debug_printf("\nDCC: ****************************\n%s", sendbuf
);
309 /* Clear the input buffer */
310 bzero(sendbuf
, sizeof(sendbuf
));
312 /* now send the body */
314 debug_printf("DCC: Writing body:\nDCC: ****************************\n");
315 (void)fseek(data_file
, SPOOL_DATA_START_OFFSET
, SEEK_SET
);
316 while((fread(sendbuf
, 1, sizeof(sendbuf
)-1, data_file
)) > 0) {
317 flushbuffer(sockfd
, sendbuf
);
318 bzero(sendbuf
, sizeof(sendbuf
));
321 debug_printf("\nDCC: ****************************\n");
323 /* shutdown() the socket */
324 if(shutdown(sockfd
, 1) < 0){
326 debug_printf("DCC: Couldn't shutdown socket: %s\n", strerror(errno
));
327 log_write(0,LOG_MAIN
,"DCC: Couldn't shutdown socket: %s\n", strerror(errno
));
328 /* If there is a problem with the shutdown()
330 (void)fclose(data_file
);
334 debug_printf("\nDCC: -------------------------\nDCC: Input sent.\nDCC: -------------------------\n");
336 /********************************
337 * receiving output from dccifd *
338 ********************************/
340 debug_printf("\nDCC: -------------------------------------\nDCC: Now receiving output from server\nDCC: -----------------------------------\n");
342 /******************************************************************
343 * We should get 3 lines: *
344 * 1/ First line is overall result: either 'A' for Accept, *
345 * 'R' for Reject, 'S' for accept Some recipients or *
346 * 'T' for a Temporary error. *
347 * 2/ Second line contains the list of Accepted/Rejected *
348 * recipients in the form AARRA (A = accepted, R = rejected). *
349 * 3/ Third line contains the X-DCC header. *
350 ******************************************************************/
352 line
= 1; /* we start at the first line of the output */
353 j
= 0; /* will be used as index for the recipients list */
354 k
= 0; /* initializing the index of the X-DCC header: dcc_header_str[k] */
356 /* Let's read from the socket until there's nothing left to read */
357 bzero(recvbuf
, sizeof(recvbuf
));
358 while((resp
= read(sockfd
, recvbuf
, sizeof(recvbuf
)-1)) > 0) {
359 /* How much did we get from the socket */
360 c
= Ustrlen(recvbuf
) + 1;
362 debug_printf("DCC: Length of the output buffer is: %d\nDCC: Output buffer is:\nDCC: ------------\nDCC: %s\nDCC: -----------\n", c
, recvbuf
);
364 /* Now let's read each character and see what we've got */
365 for(i
= 0; i
< c
; i
++) {
366 /* First check if we reached the end of the line and
367 * then increment the line counter */
368 if(recvbuf
[i
] == '\n') {
372 /* The first character of the first line is the
373 * overall response. If there's another character
374 * on that line it is not correct. */
377 /* Now get the value and set the
378 * return value accordingly */
379 if(recvbuf
[i
] == 'A') {
381 debug_printf("DCC: Overall result = A\treturning OK\n");
382 Ustrcpy(dcc_return_text
, "Mail accepted by DCC");
386 else if(recvbuf
[i
] == 'R') {
388 debug_printf("DCC: Overall result = R\treturning FAIL\n");
391 if(sender_host_name
) {
392 log_write(0, LOG_MAIN
, "H=%s [%s] F=<%s>: rejected by DCC", sender_host_name
, sender_host_address
, sender_address
);
395 log_write(0, LOG_MAIN
, "H=[%s] F=<%s>: rejected by DCC", sender_host_address
, sender_address
);
397 Ustrncpy(dcc_return_text
, dcc_reject_message
, Ustrlen(dcc_reject_message
) + 1);
399 else if(recvbuf
[i
] == 'S') {
401 debug_printf("DCC: Overall result = S\treturning OK\n");
402 Ustrcpy(dcc_return_text
, "Not all recipients accepted by DCC");
403 /* Since we're in an ACL we want a global result
404 * so we accept for all */
408 else if(recvbuf
[i
] == 'G') {
410 debug_printf("DCC: Overall result = G\treturning FAIL\n");
411 Ustrcpy(dcc_return_text
, "Greylisted by DCC");
415 else if(recvbuf
[i
] == 'T') {
417 debug_printf("DCC: Overall result = T\treturning DEFER\n");
419 log_write(0,LOG_MAIN
,"Temporary error with DCC: %s\n", recvbuf
);
420 Ustrcpy(dcc_return_text
, "Temporary error with DCC");
425 debug_printf("DCC: Overall result = something else\treturning DEFER\n");
427 log_write(0,LOG_MAIN
,"Unknown DCC response: %s\n", recvbuf
);
428 Ustrcpy(dcc_return_text
, "Unknown DCC response");
433 /* We're on the first line but not on the first character,
434 * there must be something wrong. */
436 debug_printf("DCC: Line = %d but i = %d != 0 character is %c - This is wrong!\n", line
, i
, recvbuf
[i
]);
437 log_write(0,LOG_MAIN
,"Wrong header from DCC, output is %s\n", recvbuf
);
441 /* On the second line we get a list of
442 * answers for each recipient. We don't care about
443 * it because we're in an acl and take the
447 /* The third and following lines are the X-DCC header,
448 * so we store it in dcc_header_str. */
449 /* check if we don't get more than we can handle */
450 if(k
< sizeof(dcc_header_str
)) {
451 dcc_header_str
[k
] = recvbuf
[i
];
456 debug_printf("DCC: We got more output than we can store in the X-DCC header. Truncating at 120 characters.\n");
460 /* Wrong line number. There must be a problem with the output. */
462 debug_printf("DCC: Wrong line number in output. Line number is %d\n", line
);
466 /* we reinitialize the output buffer before we read again */
467 bzero(recvbuf
,sizeof(recvbuf
));
469 /* We have read everything from the socket */
471 /* We need to terminate the X-DCC header with a '\n' character. This needs to be k-1
472 * since dcc_header_str[k] contains '\0'. */
473 dcc_header_str
[k
-1] = '\n';
475 /* Now let's sum up what we've got. */
477 debug_printf("\nDCC: --------------------------\nDCC: Overall result = %d\nDCC: X-DCC header: %sReturn message: %s\nDCC: dcc_result: %s\n", retval
, dcc_header_str
, dcc_return_text
, dcc_result
);
479 /* We only add the X-DCC header if it starts with X-DCC */
480 if(!(Ustrncmp(dcc_header_str
, "X-DCC", 5))){
481 dcc_header
= dcc_header_str
;
482 if(dcc_direct_add_header
) {
483 header_add(' ' , "%s", dcc_header_str
);
484 /* since the MIME ACL already writes the .eml file to disk without DCC Header we've to erase it */
490 debug_printf("DCC: Wrong format of the X-DCC header: %s\n", dcc_header_str
);
493 /* check if we should add additional headers passed in acl_m_dcc_add_header */
494 if(dcc_direct_add_header
) {
495 if (((xtra_hdrs
= expand_string(US
"$acl_m_dcc_add_header")) != NULL
) && (xtra_hdrs
[0] != '\0')) {
496 Ustrncpy(dcc_xtra_hdrs
, xtra_hdrs
, sizeof(dcc_xtra_hdrs
) - 2);
497 if (dcc_xtra_hdrs
[Ustrlen(dcc_xtra_hdrs
)-1] != '\n')
498 Ustrcat(dcc_xtra_hdrs
, "\n");
499 header_add(' ', "%s", dcc_xtra_hdrs
);
501 debug_printf("DCC: adding additional headers in $acl_m_dcc_add_header: %s", dcc_xtra_hdrs
);
506 /* Now return to exim main process */
508 debug_printf("DCC: Before returning to exim main process:\nDCC: return_text = %s - retval = %d\nDCC: dcc_result = %s\n", dcc_return_text
, retval
, dcc_result
);
510 (void)fclose(data_file
);