| 1 |
/* Module to send mail using the SMTP protocol. |
| 2 |
* |
| 3 |
* IRC Services is copyright (c) 1996-2009 Andrew Church. |
| 4 |
* E-mail: <achurch@achurch.org> |
| 5 |
* Parts written by Andrew Kempe and others. |
| 6 |
* This program is free but copyrighted software; see the file GPL.txt for |
| 7 |
* details. |
| 8 |
*/ |
| 9 |
|
| 10 |
#include "services.h" |
| 11 |
#include "modules.h" |
| 12 |
#include "conffile.h" |
| 13 |
#include "language.h" |
| 14 |
#include "mail.h" |
| 15 |
#include "mail-local.h" |
| 16 |
|
| 17 |
/*************************************************************************/ |
| 18 |
|
| 19 |
static char **RelayHosts; |
| 20 |
int RelayHosts_count; |
| 21 |
static char *SMTPName; |
| 22 |
|
| 23 |
static Module *module_mail_main; |
| 24 |
static typeof(low_send) *low_send_p; |
| 25 |
static typeof(low_abort) *low_abort_p; |
| 26 |
|
| 27 |
/*************************************************************************/ |
| 28 |
|
| 29 |
/* Maximum number of garbage lines to accept before disconnecting: */ |
| 30 |
#define GARBAGE_MAX 10 |
| 31 |
|
| 32 |
typedef struct SocketInfo_ { |
| 33 |
struct SocketInfo_ *next, *prev; |
| 34 |
Socket *sock; |
| 35 |
MailMessage *msg; |
| 36 |
int msg_status; |
| 37 |
int relaynum; /* Index into RelayHosts[], used to try backup servers */ |
| 38 |
enum { ST_GREETING, ST_HELO, ST_MAIL, ST_RCPT, ST_DATA, ST_FINISH } state; |
| 39 |
int replycode; /* nonzero if in the middle of a line (no EOL) */ |
| 40 |
char replychar; /* 4th character of reply (space or hyphen) */ |
| 41 |
int garbage; /* number of garbage lines seen so far */ |
| 42 |
} SocketInfo; |
| 43 |
static SocketInfo *connections; |
| 44 |
|
| 45 |
static SocketInfo *get_socketinfo(const Socket *sock, const MailMessage *msg); |
| 46 |
static void free_socketinfo(SocketInfo *si); |
| 47 |
static void try_next_relay(SocketInfo *si); |
| 48 |
static void smtp_readline(Socket *sock, void *param_unused); |
| 49 |
static void smtp_writeline(Socket *sock, const char *fmt, ...) |
| 50 |
FORMAT(printf,2,3); |
| 51 |
static void smtp_disconnect(Socket *sock, void *why); |
| 52 |
|
| 53 |
/*************************************************************************/ |
| 54 |
/***************************** Mail sending ******************************/ |
| 55 |
/*************************************************************************/ |
| 56 |
|
| 57 |
static void send_smtp(MailMessage *msg) |
| 58 |
{ |
| 59 |
SocketInfo *si; |
| 60 |
|
| 61 |
/* Remove any double quotes in the From: name and log a warning */ |
| 62 |
if (strchr(msg->fromname, '"')) { |
| 63 |
int i; |
| 64 |
module_log("warning: double quotes (\") are not allowed in the" |
| 65 |
" sender name; will be changed to single quotes (')"); |
| 66 |
for (i = 0; msg->fromname[i]; i++) { |
| 67 |
if (msg->fromname[i] == '"') |
| 68 |
msg->fromname[i] = '\''; |
| 69 |
} |
| 70 |
} |
| 71 |
|
| 72 |
/* Set up a new SocketInfo and start the connection */ |
| 73 |
si = malloc(sizeof(*si)); |
| 74 |
if (!si) { |
| 75 |
module_log("send_smtp(): no memory for SocketInfo"); |
| 76 |
send_finished(msg, MAIL_STATUS_NORSRC); |
| 77 |
return; |
| 78 |
} |
| 79 |
si->sock = sock_new(); |
| 80 |
if (!si->sock) { |
| 81 |
module_log("send_smtp(): sock_new() failed"); |
| 82 |
send_finished(msg, MAIL_STATUS_NORSRC); |
| 83 |
free(si); |
| 84 |
return; |
| 85 |
} |
| 86 |
LIST_INSERT(si, connections); |
| 87 |
module_log_debug(1, "SMTP(%p) connecting", si->sock); |
| 88 |
si->msg = msg; |
| 89 |
si->msg_status = MAIL_STATUS_ERROR; /* default--don't depend on this! */ |
| 90 |
si->state = ST_GREETING; |
| 91 |
si->replycode = 0; |
| 92 |
si->garbage = 0; |
| 93 |
sock_setcb(si->sock, SCB_READLINE, smtp_readline); |
| 94 |
sock_setcb(si->sock, SCB_DISCONNECT, smtp_disconnect); |
| 95 |
si->relaynum = -1; /* incremented by try_next_relay() */ |
| 96 |
/* Initiate connection and return */ |
| 97 |
errno = 0; /* just in case */ |
| 98 |
try_next_relay(si); |
| 99 |
} |
| 100 |
|
| 101 |
/*************************************************************************/ |
| 102 |
/*************************************************************************/ |
| 103 |
|
| 104 |
/* Auxiliary routines: */ |
| 105 |
|
| 106 |
/*************************************************************************/ |
| 107 |
|
| 108 |
/* Return the SocketInfo corresponding to the given socket or message, or |
| 109 |
* NULL if none exists. (If `sock' is non-NULL, the search is done by |
| 110 |
* socket, else by message.) |
| 111 |
*/ |
| 112 |
|
| 113 |
static SocketInfo *get_socketinfo(const Socket *sock, const MailMessage *msg) |
| 114 |
{ |
| 115 |
SocketInfo *si; |
| 116 |
|
| 117 |
LIST_FOREACH (si, connections) { |
| 118 |
if (sock ? si->sock == sock : si->msg == msg) |
| 119 |
return si; |
| 120 |
} |
| 121 |
return NULL; |
| 122 |
} |
| 123 |
|
| 124 |
/*************************************************************************/ |
| 125 |
|
| 126 |
/* Free/clear all data associated with the given SocketInfo. If a message |
| 127 |
* is still associated with the SocketInfo, abort it. |
| 128 |
*/ |
| 129 |
|
| 130 |
static void free_socketinfo(SocketInfo *si) |
| 131 |
{ |
| 132 |
if (si->msg) { |
| 133 |
send_finished(si->msg, MAIL_STATUS_ABORTED); |
| 134 |
si->msg = NULL; |
| 135 |
} |
| 136 |
if (si->sock) { |
| 137 |
/* The disconnect callback will try to call us again, so avoid |
| 138 |
* that confusing situation */ |
| 139 |
sock_setcb(si->sock, SCB_DISCONNECT, NULL); |
| 140 |
module_log_debug(1, "SMTP(%p) closed (free_socketinfo)", si->sock); |
| 141 |
sock_free(si->sock); |
| 142 |
si->sock = NULL; |
| 143 |
} |
| 144 |
LIST_REMOVE(si, connections); |
| 145 |
free(si); |
| 146 |
} |
| 147 |
|
| 148 |
/*************************************************************************/ |
| 149 |
/*************************************************************************/ |
| 150 |
|
| 151 |
/* Try connecting to the next relay in RelayHosts[]. Return 0 if a |
| 152 |
* connection was successfully initiated (but possibly not completed), else |
| 153 |
* free the SocketInfo and return -1. */ |
| 154 |
|
| 155 |
static void try_next_relay(SocketInfo *si) |
| 156 |
{ |
| 157 |
for (;;) { |
| 158 |
si->relaynum++; |
| 159 |
if (si->relaynum >= RelayHosts_count) { |
| 160 |
module_log("send_smtp(): No relay hosts available"); |
| 161 |
if (errno == ECONNREFUSED) |
| 162 |
si->msg_status = MAIL_STATUS_REFUSED; |
| 163 |
else |
| 164 |
si->msg_status = MAIL_STATUS_ERROR; |
| 165 |
send_finished(si->msg, si->msg_status); |
| 166 |
si->msg = NULL; |
| 167 |
free_socketinfo(si); |
| 168 |
return; |
| 169 |
} |
| 170 |
if (conn(si->sock, RelayHosts[si->relaynum], 25, NULL, 0) == 0) |
| 171 |
break; |
| 172 |
module_log_perror("send_smtp(): Connection to %s:25 failed", |
| 173 |
RelayHosts[si->relaynum]); |
| 174 |
} |
| 175 |
} |
| 176 |
|
| 177 |
/*************************************************************************/ |
| 178 |
|
| 179 |
/* Read a line from an SMTP socket. */ |
| 180 |
|
| 181 |
static void smtp_readline(Socket *sock, void *param_unused) |
| 182 |
{ |
| 183 |
SocketInfo *si; |
| 184 |
char buf[BUFSIZE], *s; |
| 185 |
int have_eol = 0; |
| 186 |
int replycode; |
| 187 |
|
| 188 |
|
| 189 |
if (!(si = get_socketinfo(sock, NULL))) { |
| 190 |
module_log("smtp_readline(): no SocketInfo for socket %p!", sock); |
| 191 |
sock_setcb(sock, SCB_DISCONNECT, NULL); |
| 192 |
disconn(sock); |
| 193 |
return; |
| 194 |
} |
| 195 |
|
| 196 |
sgets(buf, sizeof(buf), sock); |
| 197 |
s = buf + strlen(buf); |
| 198 |
if (s[-1] == '\n') { |
| 199 |
s--; |
| 200 |
have_eol++; |
| 201 |
} |
| 202 |
if (s[-1] == '\r') { |
| 203 |
s--; |
| 204 |
} |
| 205 |
*s = 0; |
| 206 |
module_log_debug(1, "SMTP(%p) received: %s", sock, buf); |
| 207 |
if (!si->replycode) { |
| 208 |
if (buf[0] < '1' || buf[0] > '5' |
| 209 |
|| buf[1] < '0' || buf[1] > '9' |
| 210 |
|| buf[2] < '0' || buf[2] > '9' |
| 211 |
|| (buf[3] != ' ' && buf[3] != '-')) { |
| 212 |
module_log("smtp_readline(%p) got garbage line: %s", sock, buf); |
| 213 |
si->garbage++; |
| 214 |
if (si->garbage > GARBAGE_MAX) { |
| 215 |
int count = 0; |
| 216 |
module_log("Too many garbage lines, giving up. Message was:"); |
| 217 |
module_log(" From: %s%s<%s>", |
| 218 |
si->msg->fromname ? si->msg->fromname : "", |
| 219 |
si->msg->fromname ? " " : "", si->msg->from); |
| 220 |
module_log(" To: %s", si->msg->to); |
| 221 |
module_log(" Subject: %s", si->msg->subject); |
| 222 |
s = si->msg->body; |
| 223 |
while (*s) { |
| 224 |
char *t = s + strcspn(s, "\n"); |
| 225 |
if (*t) |
| 226 |
*t++ = 0; |
| 227 |
module_log(" %s %s", count ? " " : "Body:", s); |
| 228 |
count++; |
| 229 |
s = t; |
| 230 |
} |
| 231 |
si->msg_status = MAIL_STATUS_ERROR; |
| 232 |
disconn(si->sock); |
| 233 |
return; |
| 234 |
} |
| 235 |
} |
| 236 |
si->replycode = strtol(buf, &s, 10); |
| 237 |
if (s != buf+3) { |
| 238 |
module_log("BUG: strtol ate %d characters from reply (should be" |
| 239 |
" 3)!", (int)(s-buf)); |
| 240 |
} |
| 241 |
if (si->replycode == 0) { |
| 242 |
module_log("Got bizarre response code 0 from %s", |
| 243 |
RelayHosts[si->relaynum]); |
| 244 |
si->replycode = 1; |
| 245 |
} |
| 246 |
si->replychar = buf[3]; |
| 247 |
} |
| 248 |
if (!have_eol) |
| 249 |
return; |
| 250 |
replycode = si->replycode; |
| 251 |
si->replycode = 0; |
| 252 |
if (si->replychar != ' ') |
| 253 |
return; |
| 254 |
|
| 255 |
if (replycode >= 400) { |
| 256 |
module_log("Received error reply (%d) for socket %p state %d," |
| 257 |
" aborting", replycode, sock, si->state); |
| 258 |
si->msg_status = MAIL_STATUS_REFUSED; |
| 259 |
disconn(si->sock); |
| 260 |
return; |
| 261 |
} |
| 262 |
switch (si->state++) { |
| 263 |
case ST_GREETING: |
| 264 |
smtp_writeline(sock, "HELO %s", SMTPName); |
| 265 |
break; |
| 266 |
case ST_HELO: |
| 267 |
smtp_writeline(sock, "MAIL FROM:<%s>", si->msg->from); |
| 268 |
break; |
| 269 |
case ST_MAIL: |
| 270 |
smtp_writeline(sock, "RCPT TO:<%s>", si->msg->to); |
| 271 |
break; |
| 272 |
case ST_RCPT: |
| 273 |
smtp_writeline(sock, "DATA"); |
| 274 |
break; |
| 275 |
case ST_DATA: { |
| 276 |
time_t t; |
| 277 |
time(&t); |
| 278 |
if (!strftime(buf, sizeof(buf), "%a, %d %b %Y %H:%M:%S", gmtime(&t))) |
| 279 |
strbcpy(buf, "Thu, 1 Jan 1970 00:00:00"); |
| 280 |
if (si->msg->fromname) |
| 281 |
smtp_writeline(sock, "From: \"%s\" <%s>", si->msg->fromname, |
| 282 |
si->msg->from); |
| 283 |
else |
| 284 |
smtp_writeline(sock, "From: <%s>", si->msg->from); |
| 285 |
smtp_writeline(sock, "To: <%s>", si->msg->to); |
| 286 |
smtp_writeline(sock, "Subject: %s", si->msg->subject); |
| 287 |
smtp_writeline(sock, "Date: %s +0000", buf); |
| 288 |
if (si->msg->charset) { |
| 289 |
smtp_writeline(sock, "MIME-Version: 1.0"); |
| 290 |
smtp_writeline(sock, "Content-Type: text/plain; charset=%s", |
| 291 |
si->msg->charset); |
| 292 |
} |
| 293 |
#if CLEAN_COMPILE |
| 294 |
/* writeline(sock,"") makes GCC warn about an empty format string */ |
| 295 |
smtp_writeline(sock, "%s", ""); |
| 296 |
#else |
| 297 |
smtp_writeline(sock, ""); |
| 298 |
#endif |
| 299 |
s = si->msg->body; |
| 300 |
while (*s) { |
| 301 |
char *t = s + strcspn(s, "\r\n"); |
| 302 |
if (*t == '\r') |
| 303 |
*t++ = 0; |
| 304 |
if (*t == '\n') |
| 305 |
*t++ = 0; |
| 306 |
smtp_writeline(sock, "%s%s", *s=='.' ? "." : "", s); |
| 307 |
s = t; |
| 308 |
} |
| 309 |
smtp_writeline(sock, "."); |
| 310 |
break; |
| 311 |
} /* ST_DATA */ |
| 312 |
case ST_FINISH: |
| 313 |
smtp_writeline(sock, "QUIT"); |
| 314 |
si->msg_status = MAIL_STATUS_SENT; |
| 315 |
disconn(si->sock); |
| 316 |
break; |
| 317 |
default: |
| 318 |
module_log("BUG: bad state %d for socket %p", si->state-1, sock); |
| 319 |
si->msg_status = MAIL_STATUS_ERROR; |
| 320 |
disconn(si->sock); |
| 321 |
break; |
| 322 |
} /* switch (si->state++) */ |
| 323 |
} |
| 324 |
|
| 325 |
/*************************************************************************/ |
| 326 |
|
| 327 |
static void smtp_writeline(Socket *sock, const char *fmt, ...) |
| 328 |
{ |
| 329 |
va_list args; |
| 330 |
char buf[4096]; |
| 331 |
|
| 332 |
va_start(args, fmt); |
| 333 |
vsnprintf(buf, sizeof(buf), fmt, args); |
| 334 |
va_end(args); |
| 335 |
sockprintf(sock, "%s", buf); |
| 336 |
swrite(sock, "\r\n", 2); |
| 337 |
module_log_debug(1, "SMTP(%p) sent: %s", sock, buf); |
| 338 |
} |
| 339 |
|
| 340 |
/*************************************************************************/ |
| 341 |
|
| 342 |
/* Handle a socket disconnection. */ |
| 343 |
|
| 344 |
static void smtp_disconnect(Socket *sock, void *why) |
| 345 |
{ |
| 346 |
SocketInfo *si; |
| 347 |
|
| 348 |
if (!(si = get_socketinfo(sock, NULL))) { |
| 349 |
module_log("smtp_disconnect(): no SocketInfo for socket %p!", sock); |
| 350 |
return; |
| 351 |
} |
| 352 |
|
| 353 |
module_log_debug(1, "SMTP(%p) closed (%s)", sock, |
| 354 |
why==DISCONN_LOCAL ? "local" : |
| 355 |
why==DISCONN_CONNFAIL ? "connfail" : "remote"); |
| 356 |
if (why == DISCONN_CONNFAIL) { |
| 357 |
module_log_perror("Connection to server %s failed for socket %p", |
| 358 |
RelayHosts[si->relaynum], sock); |
| 359 |
try_next_relay(si); /* will call send_finished(), etc. if needed */ |
| 360 |
return; |
| 361 |
} else if (why == DISCONN_REMOTE) { |
| 362 |
module_log("Connection to server %s broken for socket %p", |
| 363 |
RelayHosts[si->relaynum], sock); |
| 364 |
si->msg_status = MAIL_STATUS_ERROR; |
| 365 |
} |
| 366 |
send_finished(si->msg, si->msg_status); |
| 367 |
si->msg = NULL; |
| 368 |
free_socketinfo(si); |
| 369 |
} |
| 370 |
|
| 371 |
/*************************************************************************/ |
| 372 |
|
| 373 |
static void abort_smtp(MailMessage *msg) |
| 374 |
{ |
| 375 |
SocketInfo *si; |
| 376 |
|
| 377 |
if (!(si = get_socketinfo(NULL, msg))) { |
| 378 |
module_log("abort_smtp(): no SocketInfo for message %p!", msg); |
| 379 |
return; |
| 380 |
} |
| 381 |
module_log_debug(1, "SMTP(%p) aborted", si); |
| 382 |
si->msg = NULL; |
| 383 |
free_socketinfo(si); |
| 384 |
} |
| 385 |
|
| 386 |
/*************************************************************************/ |
| 387 |
/***************************** Module stuff ******************************/ |
| 388 |
/*************************************************************************/ |
| 389 |
|
| 390 |
static int do_RelayHost(const char *filename, int linenum, char *param); |
| 391 |
ConfigDirective module_config[] = { |
| 392 |
{ "RelayHost", { { CD_FUNC, CF_DIRREQ, do_RelayHost } } }, |
| 393 |
{ "SMTPName", { { CD_STRING, CF_DIRREQ, &SMTPName } } }, |
| 394 |
{ NULL } |
| 395 |
}; |
| 396 |
|
| 397 |
/*************************************************************************/ |
| 398 |
|
| 399 |
static int do_RelayHost(const char *filename, int linenum, char *param) |
| 400 |
{ |
| 401 |
static char **new_RelayHosts = NULL; |
| 402 |
static int new_RelayHosts_count = 0; |
| 403 |
int i; |
| 404 |
|
| 405 |
if (filename) { |
| 406 |
/* Check parameter for validity and save */ |
| 407 |
if (!*param) { |
| 408 |
/* Empty value */ |
| 409 |
config_error(filename, linenum, "Empty hostname in RelayHost"); |
| 410 |
} |
| 411 |
ARRAY_EXTEND(new_RelayHosts); |
| 412 |
new_RelayHosts[new_RelayHosts_count-1] = sstrdup(param); |
| 413 |
} else if (linenum == CDFUNC_INIT) { |
| 414 |
/*Prepare for reading config file: clear out "new" array just in case*/ |
| 415 |
ARRAY_FOREACH (i, new_RelayHosts) |
| 416 |
free(new_RelayHosts[i]); |
| 417 |
free(new_RelayHosts); |
| 418 |
new_RelayHosts = NULL; |
| 419 |
new_RelayHosts_count = 0; |
| 420 |
} else if (linenum == CDFUNC_SET) { |
| 421 |
/* Copy new values to config variables and clear */ |
| 422 |
ARRAY_FOREACH (i, RelayHosts) |
| 423 |
free(RelayHosts[i]); |
| 424 |
free(RelayHosts); |
| 425 |
RelayHosts = new_RelayHosts; |
| 426 |
RelayHosts_count = new_RelayHosts_count; |
| 427 |
new_RelayHosts = NULL; |
| 428 |
new_RelayHosts_count = 0; |
| 429 |
} else if (linenum == CDFUNC_DECONFIG) { |
| 430 |
/* Reset to defaults */ |
| 431 |
ARRAY_FOREACH (i, RelayHosts) |
| 432 |
free(RelayHosts[i]); |
| 433 |
free(RelayHosts); |
| 434 |
RelayHosts = NULL; |
| 435 |
RelayHosts_count = 0; |
| 436 |
} |
| 437 |
return 1; |
| 438 |
} |
| 439 |
|
| 440 |
/*************************************************************************/ |
| 441 |
|
| 442 |
static int do_load_module(Module *mod, const char *modname) |
| 443 |
{ |
| 444 |
if (strcmp(modname, "mail/main") == 0) { |
| 445 |
module_mail_main = mod; |
| 446 |
low_send_p = get_module_symbol(mod, "low_send"); |
| 447 |
if (low_send_p) |
| 448 |
*low_send_p = send_smtp; |
| 449 |
else |
| 450 |
module_log("Unable to find `low_send' symbol, cannot send mail"); |
| 451 |
low_abort_p = get_module_symbol(mod, "low_abort"); |
| 452 |
if (low_abort_p) |
| 453 |
*low_abort_p = abort_smtp; |
| 454 |
else |
| 455 |
module_log("Unable to find `low_abort' symbol, cannot send mail"); |
| 456 |
} |
| 457 |
return 0; |
| 458 |
} |
| 459 |
|
| 460 |
/*************************************************************************/ |
| 461 |
|
| 462 |
static int do_unload_module(Module *mod) |
| 463 |
{ |
| 464 |
if (mod == module_mail_main) { |
| 465 |
if (low_send_p) |
| 466 |
*low_send_p = NULL; |
| 467 |
if (low_abort_p) |
| 468 |
*low_abort_p = NULL; |
| 469 |
low_send_p = NULL; |
| 470 |
low_abort_p = NULL; |
| 471 |
module_mail_main = NULL; |
| 472 |
} |
| 473 |
return 0; |
| 474 |
} |
| 475 |
|
| 476 |
/*************************************************************************/ |
| 477 |
|
| 478 |
int init_module(void) |
| 479 |
{ |
| 480 |
Module *tmpmod; |
| 481 |
|
| 482 |
connections = NULL; |
| 483 |
|
| 484 |
if (!add_callback(NULL, "load module", do_load_module) |
| 485 |
|| !add_callback(NULL, "unload module", do_unload_module) |
| 486 |
) { |
| 487 |
module_log("Unable to add callbacks"); |
| 488 |
exit_module(0); |
| 489 |
return 0; |
| 490 |
} |
| 491 |
|
| 492 |
tmpmod = find_module("mail/main"); |
| 493 |
if (tmpmod) |
| 494 |
do_load_module(tmpmod, "mail/main"); |
| 495 |
|
| 496 |
return 1; |
| 497 |
} |
| 498 |
|
| 499 |
/*************************************************************************/ |
| 500 |
|
| 501 |
int exit_module(int shutdown_unused) |
| 502 |
{ |
| 503 |
SocketInfo *si, *si2; |
| 504 |
|
| 505 |
if (module_mail_main) |
| 506 |
do_unload_module(module_mail_main); |
| 507 |
remove_callback(NULL, "unload module", do_unload_module); |
| 508 |
remove_callback(NULL, "load module", do_load_module); |
| 509 |
|
| 510 |
LIST_FOREACH_SAFE (si, connections, si2) |
| 511 |
free_socketinfo(si); |
| 512 |
|
| 513 |
return 1; |
| 514 |
} |
| 515 |
|
| 516 |
/*************************************************************************/ |
| 517 |
|
| 518 |
/* |
| 519 |
* Local variables: |
| 520 |
* c-file-style: "stroustrup" |
| 521 |
* c-file-offsets: ((case-label . *) (statement-case-intro . *)) |
| 522 |
* indent-tabs-mode: nil |
| 523 |
* End: |
| 524 |
* |
| 525 |
* vim: expandtab shiftwidth=4: |
| 526 |
*/ |
