--- /dev/null
+/*************************************************
+* Exim - an Internet mail transport agent *
+*************************************************/
+
+/* Copyright (c) University of Cambridge 1995 - 2016 */
+/* See the file NOTICE for conditions of use and distribution. */
+
+/* Transport shim for dkim signing */
+
+#ifndef DISABLE_DKIM
+
+
+#include "exim.h"
+
+#ifdef HAVE_LINUX_SENDFILE
+#include <sys/sendfile.h>
+#endif
+
+
+static BOOL
+dkt_sign_fail(struct ob_dkim * dkim, int * errp)
+{
+if (dkim->dkim_strict)
+ {
+ uschar * dkim_strict_result = expand_string(dkim->dkim_strict);
+
+ if (dkim_strict_result)
+ if ( (strcmpic(dkim->dkim_strict, US"1") == 0) ||
+ (strcmpic(dkim->dkim_strict, US"true") == 0) )
+ {
+ /* Set errno to something halfway meaningful */
+ *errp = EACCES;
+ log_write(0, LOG_MAIN, "DKIM: message could not be signed,"
+ " and dkim_strict is set. Deferring message delivery.");
+ return FALSE;
+ }
+ }
+return TRUE;
+}
+
+static BOOL
+dkt_send_file(int out_fd, int in_fd, off_t off, size_t size)
+{
+DEBUG(D_transport) debug_printf("send file fd=%d size=%d\n", out_fd, size - off);
+
+/*XXX should implement timeout, like transport_write_block_fd() ? */
+
+/* Rewind file */
+lseek(in_fd, off, SEEK_SET);
+
+#ifdef HAVE_LINUX_SENDFILE
+/* We can use sendfile() to shove the file contents
+ to the socket. However only if we don't use TLS,
+ as then there's another layer of indirection
+ before the data finally hits the socket. */
+if (tls_out.active != out_fd)
+ {
+ ssize_t copied = 0;
+
+ while(copied >= 0 && off < size)
+ copied = sendfile(tctx->u.fd, dkim_fd, &off, size - off);
+ if (copied < 0)
+ return FALSE;
+ }
+else
+
+#endif
+
+ {
+ int sread, wwritten;
+
+ /* Send file down the original fd */
+ while((sread = read(in_fd, deliver_out_buffer, DELIVER_OUT_BUFFER_SIZE)) >0)
+ {
+ uschar * p = deliver_out_buffer;
+ /* write the chunk */
+
+ while (sread)
+ {
+#ifdef SUPPORT_TLS
+ wwritten = tls_out.active == out_fd
+ ? tls_write(FALSE, p, sread)
+ : write(out_fd, CS p, sread);
+#else
+ wwritten = write(out_fd, CS p, sread);
+#endif
+ if (wwritten == -1)
+ return FALSE;
+ p += wwritten;
+ sread -= wwritten;
+ }
+ }
+
+ if (sread == -1)
+ return FALSE;
+ }
+
+return TRUE;
+}
+
+
+
+
+/* This function is a wrapper around transport_write_message().
+ It is only called from the smtp transport if DKIM or Domainkeys support
+ is active and no transport filter is to be used.
+
+Arguments:
+ As for transport_write_message() in transort.c, with additional arguments
+ for DKIM.
+
+Returns: TRUE on success; FALSE (with errno) for any failure
+*/
+
+static BOOL
+dkt_direct(transport_ctx * tctx, struct ob_dkim * dkim,
+ const uschar ** err)
+{
+int save_fd = tctx->u.fd;
+int save_options = tctx->options;
+uschar * hdrs, * dkim_signature;
+int siglen, hsize;
+const uschar * errstr;
+BOOL rc;
+
+DEBUG(D_transport) debug_printf("dkim signing direct-mode\n");
+
+/* Get headers in string for signing and transmission */
+
+tctx->u.msg = NULL;
+tctx->options = tctx->options & ~(topt_end_dot | topt_use_bdat)
+ | topt_output_string | topt_no_body;
+
+rc = transport_write_message(tctx, 0);
+hdrs = tctx->u.msg;
+hdrs[hsize = tctx->msg_ptr] = '\0';
+
+tctx->u.fd = save_fd;
+tctx->options = save_options;
+if (!rc) return FALSE;
+
+/* Get signatures for headers plus spool data file */
+
+dkim->dot_stuffed = !!(save_options & topt_end_dot);
+
+if ((dkim_signature = dkim_exim_sign(deliver_datafile, SPOOL_DATA_START_OFFSET,
+ hdrs, dkim, &errstr)))
+ siglen = Ustrlen(dkim_signature);
+else if (!(rc = dkt_sign_fail(dkim, &errno)))
+ {
+ *err = errstr;
+ return FALSE;
+ }
+
+/* Write the signature and headers into the deliver-out-buffer. This should
+mean they go out in the same packet as the MAIL, RCPT and (first) BDAT commands
+(transport_write_message() sizes the BDAT for the buffered amount) - for short
+messages, the BDAT LAST command. We want no CRLF or dotstuffing expansion */
+
+tctx->options &= ~topt_use_crlf;
+transport_write_reset(0);
+if ( !write_chunk(tctx, dkim_signature, siglen)
+ || !write_chunk(tctx, hdrs, hsize))
+ return FALSE;
+
+tctx->options = save_options | topt_no_headers | topt_continuation;
+
+if (!(transport_write_message(tctx, 0)))
+ return FALSE;
+
+tctx->options = save_options;
+return TRUE;
+}
+
+
+/* This function is a wrapper around transport_write_message().
+ It is only called from the smtp transport if DKIM or Domainkeys support
+ is active and a transport filter is to be used. The function sets up a
+ replacement fd into a -K file, then calls the normal function. This way, the
+ exact bits that exim would have put "on the wire" will end up in the file
+ (except for TLS encapsulation, which is the very very last thing). When we
+ are done signing the file, send the signed message down the original fd (or
+ TLS fd).
+
+Arguments:
+ As for transport_write_message() in transort.c, with additional arguments
+ for DKIM.
+
+Returns: TRUE on success; FALSE (with errno) for any failure
+*/
+
+static BOOL
+dkt_via_kfile(transport_ctx * tctx, struct ob_dkim * dkim, const uschar ** err)
+{
+int dkim_fd;
+int save_errno = 0;
+BOOL rc;
+uschar * dkim_spool_name, * dkim_signature;
+int sread = 0, wwritten = 0, siglen, options;
+off_t k_file_size;
+const uschar * errstr;
+
+dkim_spool_name = spool_fname(US"input", message_subdir, message_id,
+ string_sprintf("-%d-K", (int)getpid()));
+
+DEBUG(D_transport) debug_printf("dkim signing via file %s\n", dkim_spool_name);
+
+if ((dkim_fd = Uopen(dkim_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE)) < 0)
+ {
+ /* Can't create spool file. Ugh. */
+ rc = FALSE;
+ save_errno = errno;
+ *err = string_sprintf("dkim spoolfile create: %s", strerror(errno));
+ goto CLEANUP;
+ }
+
+/* Call transport utility function to write the -K file; does the CRLF expansion
+(but, in the CHUNKING case, neither dot-stuffing nor dot-termination). */
+
+ {
+ int save_fd = tctx->u.fd;
+ tctx->u.fd = dkim_fd;
+ options = tctx->options;
+ tctx->options &= ~topt_use_bdat;
+
+ rc = transport_write_message(tctx, 0);
+
+ tctx->u.fd = save_fd;
+ tctx->options = options;
+ }
+
+/* Save error state. We must clean up before returning. */
+if (!rc)
+ {
+ save_errno = errno;
+ goto CLEANUP;
+ }
+
+/* Feed the file to the goats^W DKIM lib */
+
+dkim->dot_stuffed = !!(options & topt_end_dot);
+if ((dkim_signature = dkim_exim_sign(dkim_fd, 0, NULL, dkim, &errstr)))
+ siglen = Ustrlen(dkim_signature);
+else if (!(rc = dkt_sign_fail(dkim, &save_errno)))
+ {
+ *err = errstr;
+ goto CLEANUP;
+ }
+
+#ifndef HAVE_LINUX_SENDFILE
+if (options & topt_use_bdat)
+#endif
+ k_file_size = lseek(dkim_fd, 0, SEEK_END); /* Fetch file size */
+
+if (options & topt_use_bdat)
+ {
+ /* On big messages output a precursor chunk to get any pipelined
+ MAIL & RCPT commands flushed, then reap the responses so we can
+ error out on RCPT rejects before sending megabytes. */
+
+ if (siglen + k_file_size > DELIVER_OUT_BUFFER_SIZE && siglen > 0)
+ {
+ if ( tctx->chunk_cb(tctx, siglen, 0) != OK
+ || !transport_write_block(tctx, dkim_signature, siglen, FALSE)
+ || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
+ )
+ goto err;
+ siglen = 0;
+ }
+
+ /* Send the BDAT command for the entire message, as a single LAST-marked
+ chunk. */
+
+ if (tctx->chunk_cb(tctx, siglen + k_file_size, tc_chunk_last) != OK)
+ goto err;
+ }
+
+if(siglen > 0 && !transport_write_block(tctx, dkim_signature, siglen, TRUE))
+ goto err;
+
+if (!dkt_send_file(tctx->u.fd, dkim_fd, 0, k_file_size))
+ {
+ save_errno = errno;
+ rc = FALSE;
+ }
+
+CLEANUP:
+ /* unlink -K file */
+ (void)close(dkim_fd);
+ Uunlink(dkim_spool_name);
+ errno = save_errno;
+ return rc;
+
+err:
+ save_errno = errno;
+ rc = FALSE;
+ goto CLEANUP;
+}
+
+
+
+/***************************************************************************************************
+* External interface to write the message, while signing it with DKIM and/or Domainkeys *
+***************************************************************************************************/
+
+/* This function is a wrapper around transport_write_message().
+ It is only called from the smtp transport if DKIM or Domainkeys support
+ is compiled in.
+
+Arguments:
+ As for transport_write_message() in transort.c, with additional arguments
+ for DKIM.
+
+Returns: TRUE on success; FALSE (with errno) for any failure
+*/
+
+BOOL
+dkim_transport_write_message(transport_ctx * tctx,
+ struct ob_dkim * dkim, const uschar ** err)
+{
+/* If we can't sign, just call the original function. */
+
+if (!(dkim->dkim_private_key && dkim->dkim_domain && dkim->dkim_selector))
+ return transport_write_message(tctx, 0);
+
+/* If there is no filter command set up, construct the message and calculate
+a dkim signature of it, send the signature and a reconstructed message. This
+avoids using a temprary file. */
+
+if ( !transport_filter_argv
+ || !*transport_filter_argv
+ || !**transport_filter_argv
+ )
+ return dkt_direct(tctx, dkim, err);
+
+/* Use the transport path to write a file, calculate a dkim signature,
+send the signature and then send the file. */
+
+return dkt_via_kfile(tctx, dkim, err);
+}
+
+#endif /* whole file */
+
+/* vi: aw ai sw=2
+*/
+/* End of dkim_transport.c */
#include "exim.h"
-#ifdef HAVE_LINUX_SENDFILE
-#include <sys/sendfile.h>
-#endif
-
/* Structure for keeping list of addresses that have been added to
Envelope-To:, in order to avoid duplication. */
longstop.
Arguments:
- fd file descriptor to write to
+ tctx transport context: file descriptor or string to write to
block block of bytes to write
len number of bytes to write
transport_count is incremented by the number of bytes written
*/
-BOOL
-transport_write_block(int fd, uschar *block, int len)
+static BOOL
+transport_write_block_fd(transport_ctx * tctx, uschar *block, int len, BOOL more)
{
int i, rc, save_errno;
int local_timeout = transport_write_timeout;
+int fd = tctx->u.fd;
/* This loop is for handling incomplete writes and other retries. In most
normal cases, it is only ever executed once. */
for (i = 0; i < 100; i++)
{
DEBUG(D_transport)
- debug_printf("writing data block fd=%d size=%d timeout=%d\n",
- fd, len, local_timeout);
+ debug_printf("writing data block fd=%d size=%d timeout=%d%s\n",
+ fd, len, local_timeout, more ? " (more expected)" : "");
/* This code makes use of alarm() in order to implement the timeout. This
isn't a very tidy way of doing things. Using non-blocking I/O with select()
if (transport_write_timeout <= 0) /* No timeout wanted */
{
- #ifdef SUPPORT_TLS
- if (tls_out.active == fd) rc = tls_write(FALSE, block, len); else
- #endif
- rc = write(fd, block, len);
+ rc =
+#ifdef SUPPORT_TLS
+ (tls_out.active == fd) ? tls_write(FALSE, block, len) :
+#endif
+#ifdef MSG_MORE
+ more ? send(fd, block, len, MSG_MORE) :
+#endif
+ write(fd, block, len);
save_errno = errno;
}
else
{
alarm(local_timeout);
+
+ rc =
#ifdef SUPPORT_TLS
- if (tls_out.active == fd)
- rc = tls_write(FALSE, block, len);
- else
+ (tls_out.active == fd) ? tls_write(FALSE, block, len) :
+#endif
+#ifdef MSG_MORE
+ more ? send(fd, block, len, MSG_MORE) :
#endif
- rc = write(fd, block, len);
+ write(fd, block, len);
+
save_errno = errno;
local_timeout = alarm(0);
if (sigalrm_seen)
}
+BOOL
+transport_write_block(transport_ctx * tctx, uschar *block, int len, BOOL more)
+{
+if (!(tctx->options & topt_output_string))
+ return transport_write_block_fd(tctx, block, len, more);
+
+/* Write to expanding-string. NOTE: not NUL-terminated */
+
+if (!tctx->u.msg)
+ {
+ tctx->u.msg = store_get(tctx->msg_size = 1024);
+ tctx->msg_ptr = 0;
+ }
+
+tctx->u.msg = string_catn(tctx->u.msg, &tctx->msg_size, &tctx->msg_ptr, block, len);
+return TRUE;
+}
+
+
/*************************************************
BOOL
transport_write_string(int fd, const char *format, ...)
{
+transport_ctx tctx = {0};
va_list ap;
va_start(ap, format);
if (!string_vformat(big_buffer, big_buffer_size, format, ap))
log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong formatted string in transport");
va_end(ap);
-return transport_write_block(fd, big_buffer, Ustrlen(big_buffer));
+tctx.u.fd = fd;
+return transport_write_block(&tctx, big_buffer, Ustrlen(big_buffer), FALSE);
}
+void
+transport_write_reset(int options)
+{
+if (!(options & topt_continuation)) chunk_ptr = deliver_out_buffer;
+nl_partial_match = -1;
+nl_check_length = nl_escape_length = 0;
+}
+
+
+
/*************************************************
* Write character chunk *
*************************************************/
chunk was NL, or matched part of the data that has to be escaped.
Arguments:
- fd file descript to write to
+ tctx transport context - processing to be done during output,
+ and file descriptor to write to
chunk pointer to data to write
len length of data to write
- tctx transport context - processing to be done during output
In addition, the static nl_xxx variables must be set as required.
Returns: TRUE on success, FALSE on failure (with errno preserved)
*/
-static BOOL
-write_chunk(int fd, transport_ctx * tctx, uschar *chunk, int len)
+BOOL
+write_chunk(transport_ctx * tctx, uschar *chunk, int len)
{
uschar *start = chunk;
uschar *end = chunk + len;
if (tctx && tctx->options & topt_use_bdat && tctx->chunk_cb)
{
if ( tctx->chunk_cb(tctx, (unsigned)len, 0) != OK
- || !transport_write_block(fd, deliver_out_buffer, len)
+ || !transport_write_block(tctx, deliver_out_buffer, len, FALSE)
|| tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
)
return FALSE;
}
else
- if (!transport_write_block(fd, deliver_out_buffer, len))
+ if (!transport_write_block(tctx, deliver_out_buffer, len, FALSE))
return FALSE;
chunk_ptr = deliver_out_buffer;
}
pplist address of anchor of the list of addresses not to output
pdlist address of anchor of the list of processed addresses
first TRUE if this is the first address; set it FALSE afterwards
- fd the file descriptor to write to
tctx transport context - processing to be done during output
+ and the file descriptor to write to
Returns: FALSE if writing failed
*/
static BOOL
write_env_to(address_item *p, struct aci **pplist, struct aci **pdlist,
- BOOL *first, int fd, transport_ctx * tctx)
+ BOOL *first, transport_ctx * tctx)
{
address_item *pp;
struct aci *ppp;
address_item *dup;
for (dup = addr_duplicate; dup; dup = dup->next)
if (dup->dupof == pp) /* a dup of our address */
- if (!write_env_to(dup, pplist, pdlist, first, fd, tctx))
+ if (!write_env_to(dup, pplist, pdlist, first, tctx))
return FALSE;
if (!pp->parent) break;
}
*pplist = ppp;
ppp->ptr = pp;
-if (!*first && !write_chunk(fd, tctx, US",\n ", 3)) return FALSE;
+if (!*first && !write_chunk(tctx, US",\n ", 3)) return FALSE;
*first = FALSE;
-return write_chunk(fd, tctx, pp->address, Ustrlen(pp->address));
+return write_chunk(tctx, pp->address, Ustrlen(pp->address));
}
Arguments:
addr (chain of) addresses (for extra headers), or NULL;
only the first address is used
- fd file descriptor to write the message to
tctx transport context
sendfn function for output (transport or verify)
Returns: TRUE on success; FALSE on failure.
*/
BOOL
-transport_headers_send(int fd, transport_ctx * tctx,
- BOOL (*sendfn)(int fd, transport_ctx * tctx, uschar * s, int len))
+transport_headers_send(transport_ctx * tctx,
+ BOOL (*sendfn)(transport_ctx * tctx, uschar * s, int len))
{
header_line *h;
const uschar *list;
if ((hh = rewrite_header(h, NULL, NULL, tblock->rewrite_rules,
tblock->rewrite_existflags, FALSE)))
{
- if (!sendfn(fd, tctx, hh->text, hh->slen)) return FALSE;
+ if (!sendfn(tctx, hh->text, hh->slen)) return FALSE;
store_reset(reset_point);
continue; /* With the next header line */
}
/* Either no rewriting rules, or it didn't get rewritten */
- if (!sendfn(fd, tctx, h->text, h->slen)) return FALSE;
+ if (!sendfn(tctx, h->text, h->slen)) return FALSE;
}
/* Header removed */
hprev = h;
if (i == 1)
{
- if (!sendfn(fd, tctx, h->text, h->slen)) return FALSE;
+ if (!sendfn(tctx, h->text, h->slen)) return FALSE;
DEBUG(D_transport)
debug_printf("added header line(s):\n%s---\n", h->text);
}
int len = Ustrlen(s);
if (len > 0)
{
- if (!sendfn(fd, tctx, s, len)) return FALSE;
- if (s[len-1] != '\n' && !sendfn(fd, tctx, US"\n", 1))
+ if (!sendfn(tctx, s, len)) return FALSE;
+ if (s[len-1] != '\n' && !sendfn(tctx, US"\n", 1))
return FALSE;
DEBUG(D_transport)
{
/* Separate headers from body with a blank line */
-return sendfn(fd, tctx, US"\n", 1);
+return sendfn(tctx, US"\n", 1);
}
transport_write_timeout non-zero.
Arguments:
- fd file descriptor to write the message to
tctx
+ (fd, msg) Either and fd, to write the message to,
+ or a string: if null write message to allocated space
+ otherwire take content as headers.
addr (chain of) addresses (for extra headers), or NULL;
only the first address is used
tblock optional transport instance block (NULL signifies NULL/0):
is incremented by the number of bytes written.
*/
-static BOOL
-internal_transport_write_message(int fd, transport_ctx * tctx, int size_limit)
+BOOL
+internal_transport_write_message(transport_ctx * tctx, int size_limit)
{
int len;
/* Initialize pointer in output buffer. */
-chunk_ptr = deliver_out_buffer;
+transport_write_reset(tctx->options);
/* Set up the data for start-of-line data checking and escaping */
-nl_partial_match = -1;
if (tctx->check_string && tctx->escape_string)
{
nl_check = tctx->check_string;
nl_escape = tctx->escape_string;
nl_escape_length = Ustrlen(nl_escape);
}
-else
- nl_check_length = nl_escape_length = 0;
-
-/* Whether the escaping mechanism is applied to headers or not is controlled by
-an option (set for SMTP, not otherwise). Negate the length if not wanted till
-after the headers. */
-
-if (!(tctx->options & topt_escape_headers))
- nl_check_length = -nl_check_length;
/* Write the headers if required, including any that have to be added. If there
are header rewriting rules, apply them. */
if (!(tctx->options & topt_no_headers))
{
+ /* Whether the escaping mechanism is applied to headers or not is controlled by
+ an option (set for SMTP, not otherwise). Negate the length if not wanted till
+ after the headers. */
+
+ if (!(tctx->options & topt_escape_headers))
+ nl_check_length = -nl_check_length;
+
/* Add return-path: if requested. */
if (tctx->options & topt_add_return_path)
uschar buffer[ADDRESS_MAXLENGTH + 20];
int n = sprintf(CS buffer, "Return-path: <%.*s>\n", ADDRESS_MAXLENGTH,
return_path);
- if (!write_chunk(fd, tctx, buffer, n)) return FALSE;
+ if (!write_chunk(tctx, buffer, n)) return FALSE;
}
/* Add envelope-to: if requested */
struct aci *dlist = NULL;
void *reset_point = store_get(0);
- if (!write_chunk(fd, tctx, US"Envelope-to: ", 13)) return FALSE;
+ if (!write_chunk(tctx, US"Envelope-to: ", 13)) return FALSE;
/* Pick up from all the addresses. The plist and dlist variables are
anchors for lists of addresses already handled; they have to be defined at
this level because write_env_to() calls itself recursively. */
for (p = tctx->addr; p; p = p->next)
- if (!write_env_to(p, &plist, &dlist, &first, fd, tctx))
+ if (!write_env_to(p, &plist, &dlist, &first, tctx))
return FALSE;
/* Add a final newline and reset the store used for tracking duplicates */
- if (!write_chunk(fd, tctx, US"\n", 1)) return FALSE;
+ if (!write_chunk(tctx, US"\n", 1)) return FALSE;
store_reset(reset_point);
}
{
uschar buffer[100];
int n = sprintf(CS buffer, "Delivery-date: %s\n", tod_stamp(tod_full));
- if (!write_chunk(fd, tctx, buffer, n)) return FALSE;
+ if (!write_chunk(tctx, buffer, n)) return FALSE;
}
/* Then the message's headers. Don't write any that are flagged as "old";
match any entries therein. Then check addr->prop.remove_headers too, provided that
addr is not NULL. */
- if (!transport_headers_send(fd, tctx, &write_chunk))
+ if (!transport_headers_send(tctx, &write_chunk))
return FALSE;
}
size = hsize + fsize;
if (tctx->options & topt_use_crlf)
size += body_linecount; /* account for CRLF-expansion */
+
+ /* With topt_use_bdat we never do dot-stuffing; no need to
+ account for any expansion due to that. */
}
/* If the message is large, emit first a non-LAST chunk with just the
DEBUG(D_transport)
debug_printf("sending small initial BDAT; hsize=%d\n", hsize);
if ( tctx->chunk_cb(tctx, hsize, 0) != OK
- || !transport_write_block(fd, deliver_out_buffer, hsize)
+ || !transport_write_block(tctx, deliver_out_buffer, hsize, FALSE)
|| tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
)
return FALSE;
while ( (len = MAX(DELIVER_IN_BUFFER_SIZE, size)) > 0
&& (len = read(deliver_datafile, deliver_in_buffer, len)) > 0)
{
- if (!write_chunk(fd, tctx, deliver_in_buffer, len))
+ if (!write_chunk(tctx, deliver_in_buffer, len))
return FALSE;
size -= len;
}
/* If requested, add a terminating "." line (SMTP output). */
-if (tctx->options & topt_end_dot && !write_chunk(fd, tctx, US".\n", 2))
+if (tctx->options & topt_end_dot && !write_chunk(tctx, US".\n", 2))
return FALSE;
/* Write out any remaining data in the buffer before returning. */
return (len = chunk_ptr - deliver_out_buffer) <= 0 ||
- transport_write_block(fd, deliver_out_buffer, len);
-}
-
-
-#ifndef DISABLE_DKIM
-
-/***************************************************************************************************
-* External interface to write the message, while signing it with DKIM and/or Domainkeys *
-***************************************************************************************************/
-
-/* This function is a wrapper around transport_write_message().
- It is only called from the smtp transport if DKIM or Domainkeys support
- is compiled in. The function sets up a replacement fd into a -K file,
- then calls the normal function. This way, the exact bits that exim would
- have put "on the wire" will end up in the file (except for TLS
- encapsulation, which is the very very last thing). When we are done
- signing the file, send the signed message down the original fd (or TLS fd).
-
-Arguments:
- as for internal_transport_write_message() above, with additional arguments
- for DKIM.
-
-Returns: TRUE on success; FALSE (with errno) for any failure
-*/
-
-BOOL
-dkim_transport_write_message(int out_fd, transport_ctx * tctx,
- struct ob_dkim * dkim, const uschar ** err)
-{
-int dkim_fd;
-int save_errno = 0;
-BOOL rc;
-uschar * dkim_spool_name;
-uschar * dkim_signature = NULL;
-int sread = 0, wwritten = 0, siglen = 0, options;
-off_t k_file_size;
-const uschar * errstr;
-
-/* If we can't sign, just call the original function. */
-
-if (!(dkim->dkim_private_key && dkim->dkim_domain && dkim->dkim_selector))
- return transport_write_message(out_fd, tctx, 0);
-
-dkim_spool_name = spool_fname(US"input", message_subdir, message_id,
- string_sprintf("-%d-K", (int)getpid()));
-
-if ((dkim_fd = Uopen(dkim_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE)) < 0)
- {
- /* Can't create spool file. Ugh. */
- rc = FALSE;
- save_errno = errno;
- *err = string_sprintf("dkim spoolfile create: %s", strerror(errno));
- goto CLEANUP;
- }
-
-/* Call original function to write the -K file; does the CRLF expansion
-(but, in the CHUNKING case, not dot-stuffing and dot-termination). */
-
-options = tctx->options;
-tctx->options &= ~topt_use_bdat;
-rc = transport_write_message(dkim_fd, tctx, 0);
-tctx->options = options;
-
-/* Save error state. We must clean up before returning. */
-if (!rc)
- {
- save_errno = errno;
- goto CLEANUP;
- }
-
-/* Rewind file and feed it to the goats^W DKIM lib */
-dkim->dot_stuffed = !!(options & topt_end_dot);
-lseek(dkim_fd, 0, SEEK_SET);
-if ((dkim_signature = dkim_exim_sign(dkim_fd, dkim, &errstr)))
- siglen = Ustrlen(dkim_signature);
-else if (dkim->dkim_strict)
- {
- uschar *dkim_strict_result = expand_string(dkim->dkim_strict);
- if (dkim_strict_result)
- if ( (strcmpic(dkim->dkim_strict,US"1") == 0) ||
- (strcmpic(dkim->dkim_strict,US"true") == 0) )
- {
- /* Set errno to something halfway meaningful */
- save_errno = EACCES;
- log_write(0, LOG_MAIN, "DKIM: message could not be signed,"
- " and dkim_strict is set. Deferring message delivery.");
- *err = errstr;
- rc = FALSE;
- goto CLEANUP;
- }
- }
-
-#ifndef HAVE_LINUX_SENDFILE
-if (options & topt_use_bdat)
-#endif
- k_file_size = lseek(dkim_fd, 0, SEEK_END); /* Fetch file size */
-
-if (options & topt_use_bdat)
- {
-
- /* On big messages output a precursor chunk to get any pipelined
- MAIL & RCPT commands flushed, then reap the responses so we can
- error out on RCPT rejects before sending megabytes. */
-
- if (siglen + k_file_size > DELIVER_OUT_BUFFER_SIZE && siglen > 0)
- {
- if ( tctx->chunk_cb(tctx, siglen, 0) != OK
- || !transport_write_block(out_fd, dkim_signature, siglen)
- || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
- )
- goto err;
- siglen = 0;
- }
-
- /* Send the BDAT command for the entire message, as a single LAST-marked
- chunk. */
-
- if (tctx->chunk_cb(tctx, siglen + k_file_size, tc_chunk_last) != OK)
- goto err;
- }
-
-if(siglen > 0 && !transport_write_block(out_fd, dkim_signature, siglen))
- goto err;
-
-#ifdef HAVE_LINUX_SENDFILE
-/* We can use sendfile() to shove the file contents
- to the socket. However only if we don't use TLS,
- as then there's another layer of indirection
- before the data finally hits the socket. */
-if (tls_out.active != out_fd)
- {
- ssize_t copied = 0;
- off_t offset = 0;
-
- /* Rewind file */
- lseek(dkim_fd, 0, SEEK_SET);
-
- while(copied >= 0 && offset < k_file_size)
- copied = sendfile(out_fd, dkim_fd, &offset, k_file_size - offset);
- if (copied < 0)
- goto err;
- }
-else
-
-#endif
-
- {
- /* Rewind file */
- lseek(dkim_fd, 0, SEEK_SET);
-
- /* Send file down the original fd */
- while((sread = read(dkim_fd, deliver_out_buffer, DELIVER_OUT_BUFFER_SIZE)) >0)
- {
- uschar * p = deliver_out_buffer;
- /* write the chunk */
-
- while (sread)
- {
-#ifdef SUPPORT_TLS
- wwritten = tls_out.active == out_fd
- ? tls_write(FALSE, p, sread)
- : write(out_fd, CS p, sread);
-#else
- wwritten = write(out_fd, CS p, sread);
-#endif
- if (wwritten == -1)
- goto err;
- p += wwritten;
- sread -= wwritten;
- }
- }
-
- if (sread == -1)
- {
- save_errno = errno;
- rc = FALSE;
- }
- }
-
-CLEANUP:
- /* unlink -K file */
- (void)close(dkim_fd);
- Uunlink(dkim_spool_name);
- errno = save_errno;
- return rc;
-
-err:
- save_errno = errno;
- rc = FALSE;
- goto CLEANUP;
+ transport_write_block(tctx, deliver_out_buffer, len, FALSE);
}
-#endif
-
/*************************************************
the real work, passing over all the arguments from this function. Otherwise,
set up a filtering process, fork another process to call the internal function
to write to the filter, and in this process just suck from the filter and write
-down the given fd. At the end, tidy up the pipes and the processes.
+down the fd in the transport context. At the end, tidy up the pipes and the
+processes.
Arguments: as for internal_transport_write_message() above
*/
BOOL
-transport_write_message(int fd, transport_ctx * tctx, int size_limit)
+transport_write_message(transport_ctx * tctx, int size_limit)
{
BOOL last_filter_was_NL = TRUE;
int rc, len, yield, fd_read, fd_write, save_errno;
pid_t filter_pid, write_pid;
static transport_ctx dummy_tctx = {0};
-if (!tctx) tctx = &dummy_tctx;
-
transport_filter_timed_out = FALSE;
/* If there is no filter command set up, call the internal function that does
|| !*transport_filter_argv
|| !**transport_filter_argv
)
- return internal_transport_write_message(fd, tctx, size_limit);
+ return internal_transport_write_message(tctx, size_limit);
/* Otherwise the message must be written to a filter process and read back
before being written to the incoming fd. First set up the special processing to
write_pid = (pid_t)(-1);
{
- int bits = fcntl(fd, F_GETFD);
- (void)fcntl(fd, F_SETFD, bits | FD_CLOEXEC);
+ int bits = fcntl(tctx->u.fd, F_GETFD);
+ (void)fcntl(tctx->u.fd, F_SETFD, bits | FD_CLOEXEC);
filter_pid = child_open(USS transport_filter_argv, NULL, 077,
&fd_write, &fd_read, FALSE);
- (void)fcntl(fd, F_SETFD, bits & ~FD_CLOEXEC);
+ (void)fcntl(tctx->u.fd, F_SETFD, bits & ~FD_CLOEXEC);
}
if (filter_pid < 0) goto TIDY_UP; /* errno set */
(void)close(pfd[pipe_read]);
nl_check_length = nl_escape_length = 0;
+ tctx->u.fd = fd_write;
tctx->check_string = tctx->escape_string = NULL;
tctx->options &= ~(topt_use_crlf | topt_end_dot | topt_use_bdat);
- rc = internal_transport_write_message(fd_write, tctx, size_limit);
+ rc = internal_transport_write_message(tctx, size_limit);
save_errno = errno;
if ( write(pfd[pipe_write], (void *)&rc, sizeof(BOOL))
if (len > 0)
{
- if (!write_chunk(fd, tctx, deliver_in_buffer, len)) goto TIDY_UP;
+ if (!write_chunk(tctx, deliver_in_buffer, len)) goto TIDY_UP;
last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
}
nl_check_length = nl_escape_length = 0;
if ( tctx->options & topt_end_dot
&& ( last_filter_was_NL
- ? !write_chunk(fd, tctx, US".\n", 2)
- : !write_chunk(fd, tctx, US"\n.\n", 3)
+ ? !write_chunk(tctx, US".\n", 2)
+ : !write_chunk(tctx, US"\n.\n", 3)
) )
yield = FALSE;
else
yield = (len = chunk_ptr - deliver_out_buffer) <= 0
- || transport_write_block(fd, deliver_out_buffer, len);
+ || transport_write_block(tctx, deliver_out_buffer, len, FALSE);
}
else
errno = save_errno; /* From some earlier error */