Gitweb:
http://git.exim.org/exim.git/commitdiff/bd21a787cdeef803334a6c7bf50d23b2a18cbd6f
Commit: bd21a787cdeef803334a6c7bf50d23b2a18cbd6f
Parent: a9764ac59781eec7ec4d0099d6c849059f7efc42
Author: Wolfgang Breyha <wbreyha@???>
AuthorDate: Sun Sep 28 13:40:45 2014 +0100
Committer: Jeremy Harris <jgh146exb@???>
CommitDate: Sun Sep 28 13:47:39 2014 +0100
Fix transport-results pipe for multiple recipients combined with certs.
The previous parsing failed when a result item split over a buffer boundary;
fix by prefixing sizes to items, and checking enough has been read as the
initial parsing stage.
---
doc/doc-txt/ChangeLog | 7 ++
src/src/deliver.c | 162 ++++++++++++++++++++++++++++++++++++-------------
src/src/macros.h | 4 +
3 files changed, 131 insertions(+), 42 deletions(-)
diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index 46fed6f..76ecc20 100644
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -37,6 +37,13 @@ TL/04 Bugzilla 1216: Add -M (related messages) option to exigrep.
TL/05 GitHub Issue 18: Adjust logic testing for true/false in redis lookups.
Merged patch from Sebastian Wiedenroth.
+JH/05 Fix results-pipe from transport process. Several recipients, combined
+ with certificate use, exposed issues where response data items split
+ over buffer boundaries were not parsed properly. This eventually
+ resulted in duplicates being sent. This issue only became common enough
+ to notice due to the introduction of conection certificate information,
+ the item size being so much larger. Found and fixed by Wolfgang Breyha.
+
Exim version 4.84
-----------------
TL/01 Bugzilla 1506: Re-add a 'return NULL' to silence complaints from static
diff --git a/src/src/deliver.c b/src/src/deliver.c
index a598e25..2ee69d3 100644
--- a/src/src/deliver.c
+++ b/src/src/deliver.c
@@ -2883,6 +2883,8 @@ uschar *ptr = endptr;
uschar *msg = p->msg;
BOOL done = p->done;
BOOL unfinished = TRUE;
+/* minimum size to read is header size including id, subid and length */
+int required = PIPE_HEADER_SIZE;
/* Loop through all items, reading from the pipe when necessary. The pipe
is set up to be non-blocking, but there are two different Unix mechanisms in
@@ -2905,12 +2907,15 @@ while (!done)
{
retry_item *r, **rp;
int remaining = endptr - ptr;
+ uschar header[PIPE_HEADER_SIZE + 1];
+ uschar id, subid;
+ uschar *endc;
/* Read (first time) or top up the chars in the buffer if necessary.
There will be only one read if we get all the available data (i.e. don't
fill the buffer completely). */
- if (remaining < 2500 && unfinished)
+ if (remaining < required && unfinished)
{
int len;
int available = big_buffer_size - remaining;
@@ -2943,17 +2948,64 @@ while (!done)
won't read any more, as "unfinished" will get set FALSE. */
endptr += len;
+ remaining += len;
unfinished = len == available;
}
/* If we are at the end of the available data, exit the loop. */
-
if (ptr >= endptr) break;
+ /* copy and read header */
+ memcpy(header, ptr, PIPE_HEADER_SIZE);
+ header[PIPE_HEADER_SIZE] = '\0';
+ id = header[0];
+ subid = header[1];
+ required = Ustrtol(header + 2, &endc, 10) + PIPE_HEADER_SIZE; /* header + data */
+ if (*endc)
+ {
+ msg = string_sprintf("failed to read pipe from transport process "
+ "%d for transport %s: error reading size from header", pid, addr->transport->driver_name);
+ done = TRUE;
+ break;
+ }
+
+ DEBUG(D_deliver)
+ debug_printf("header read id:%c,subid:%c,size:%s,required:%d,remaining:%d,unfinished:%d\n",
+ id, subid, header+2, required, remaining, unfinished);
+
+ /* is there room for the dataset we want to read ? */
+ if (required > big_buffer_size - PIPE_HEADER_SIZE)
+ {
+ msg = string_sprintf("failed to read pipe from transport process "
+ "%d for transport %s: big_buffer too small! required size=%d buffer size=%d", pid, addr->transport->driver_name,
+ required, big_buffer_size - PIPE_HEADER_SIZE);
+ done = TRUE;
+ break;
+ }
+
+ /* we wrote all datasets with atomic write() calls
+ remaining < required only happens if big_buffer was too small
+ to get all available data from pipe. unfinished has to be true
+ as well. */
+ if (remaining < required)
+ if (unfinished)
+ continue;
+ else
+ {
+ msg = string_sprintf("failed to read pipe from transport process "
+ "%d for transport %s: required size=%d > remaining size=%d and unfinished=false",
+ pid, addr->transport->driver_name, required, remaining);
+ done = TRUE;
+ break;
+ }
+
+ /* step behind the header */
+ ptr += PIPE_HEADER_SIZE;
+
/* Handle each possible type of item, assuming the complete item is
available in store. */
- switch (*ptr++)
+ switch (id)
{
/* Host items exist only if any hosts were marked unusable. Match
up by checking the IP address. */
@@ -3050,7 +3102,7 @@ while (!done)
#ifdef SUPPORT_TLS
case 'X':
if (addr == NULL) goto ADDR_MISMATCH; /* Below, in 'A' handler */
- switch (*ptr++)
+ switch (subid)
{
case '1':
addr->cipher = NULL;
@@ -3088,7 +3140,7 @@ while (!done)
#endif /*SUPPORT_TLS*/
case 'C': /* client authenticator information */
- switch (*ptr++)
+ switch (subid)
{
case '1':
addr->authenticator = (*ptr)? string_copy(ptr) : NULL;
@@ -3111,7 +3163,7 @@ while (!done)
#ifdef EXPERIMENTAL_DSN
case 'D':
- if (addr == NULL) break;
+ if (addr == NULL) goto ADDR_MISMATCH;
memcpy(&(addr->dsn_aware), ptr, sizeof(addr->dsn_aware));
ptr += sizeof(addr->dsn_aware);
DEBUG(D_deliver) debug_printf("DSN read: addr->dsn_aware = %d\n", addr->dsn_aware);
@@ -3179,7 +3231,7 @@ while (!done)
continue_hostname = NULL;
}
done = TRUE;
- DEBUG(D_deliver) debug_printf("Z%c item read\n", *ptr);
+ DEBUG(D_deliver) debug_printf("Z0%c item read\n", *ptr);
break;
/* Anything else is a disaster. */
@@ -3632,9 +3684,40 @@ while (parcount > max)
static void
-rmt_dlv_checked_write(int fd, void * buf, int size)
+rmt_dlv_checked_write(int fd, char id, char subid, void * buf, int size)
{
-int ret = write(fd, buf, size);
+uschar writebuffer[PIPE_HEADER_SIZE + BIG_BUFFER_SIZE];
+int header_length;
+
+/* we assume that size can't get larger then BIG_BUFFER_SIZE which currently is set to 16k */
+/* complain to log if someone tries with buffer sizes we can't handle*/
+
+if (size > 99999)
+{
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE,
+ "Failed writing transport result to pipe: can't handle buffers > 99999 bytes. truncating!\n");
+ size = 99999;
+}
+
+/* to keep the write() atomic we build header in writebuffer and copy buf behind */
+/* two write() calls would increase the complexity of reading from pipe */
+
+/* convert size to human readable string prepended by id and subid */
+header_length = snprintf(writebuffer, PIPE_HEADER_SIZE+1, "%c%c%05d", id, subid, size);
+if (header_length != PIPE_HEADER_SIZE)
+{
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "header snprintf failed\n");
+ writebuffer[0] = '\0';
+}
+
+DEBUG(D_deliver) debug_printf("header write id:%c,subid:%c,size:%d,final:%s\n",
+ id, subid, size, writebuffer);
+
+if (buf && size > 0)
+ memcpy(writebuffer + PIPE_HEADER_SIZE, buf, size);
+
+size += PIPE_HEADER_SIZE;
+int ret = write(fd, writebuffer, size);
if(ret != size)
log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Failed writing transport result to pipe: %s\n",
ret == -1 ? strerror(errno) : "short write");
@@ -4160,8 +4243,8 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
for (h = addr->host_list; h != NULL; h = h->next)
{
if (h->address == NULL || h->status < hstatus_unusable) continue;
- sprintf(CS big_buffer, "H%c%c%s", h->status, h->why, h->address);
- rmt_dlv_checked_write(fd, big_buffer, Ustrlen(big_buffer+3) + 4);
+ sprintf(CS big_buffer, "%c%c%s", h->status, h->why, h->address);
+ rmt_dlv_checked_write(fd, 'H', '0', big_buffer, Ustrlen(big_buffer+2) + 3);
}
/* The number of bytes written. This is the same for each address. Even
@@ -4169,9 +4252,8 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
size of each one is the same, and it's that value we have got because
transport_count gets reset before calling transport_write_message(). */
- big_buffer[0] = 'S';
- memcpy(big_buffer+1, &transport_count, sizeof(transport_count));
- rmt_dlv_checked_write(fd, big_buffer, sizeof(transport_count) + 1);
+ memcpy(big_buffer, &transport_count, sizeof(transport_count));
+ rmt_dlv_checked_write(fd, 'S', '0', big_buffer, sizeof(transport_count));
/* Information about what happened to each address. Four item types are
used: an optional 'X' item first, for TLS information, then an optional "C"
@@ -4194,7 +4276,7 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
if (addr->cipher)
{
ptr = big_buffer;
- sprintf(CS ptr, "X1%.128s", addr->cipher);
+ sprintf(CS ptr, "%.128s", addr->cipher);
while(*ptr++);
if (!addr->peerdn)
*ptr++ = 0;
@@ -4204,35 +4286,33 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
while(*ptr++);
}
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'X', '1', big_buffer, ptr - big_buffer);
}
if (addr->peercert)
{
ptr = big_buffer;
- *ptr++ = 'X'; *ptr++ = '2';
if (!tls_export_cert(ptr, big_buffer_size-2, addr->peercert))
while(*ptr++);
else
*ptr++ = 0;
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'X', '2', big_buffer, ptr - big_buffer);
}
if (addr->ourcert)
{
ptr = big_buffer;
- *ptr++ = 'X'; *ptr++ = '3';
if (!tls_export_cert(ptr, big_buffer_size-2, addr->ourcert))
while(*ptr++);
else
*ptr++ = 0;
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'X', '3', big_buffer, ptr - big_buffer);
}
# ifndef DISABLE_OCSP
if (addr->ocsp > OCSP_NOT_REQ)
{
ptr = big_buffer;
- sprintf(CS ptr, "X4%c", addr->ocsp + '0');
+ sprintf(CS ptr, "%c", addr->ocsp + '0');
while(*ptr++);
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'X', '4', big_buffer, ptr - big_buffer);
}
# endif
#endif /*SUPPORT_TLS*/
@@ -4240,34 +4320,33 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
if (client_authenticator)
{
ptr = big_buffer;
- sprintf(CS big_buffer, "C1%.64s", client_authenticator);
+ sprintf(CS big_buffer, "%.64s", client_authenticator);
while(*ptr++);
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'C', '1', big_buffer, ptr - big_buffer);
}
if (client_authenticated_id)
{
ptr = big_buffer;
- sprintf(CS big_buffer, "C2%.64s", client_authenticated_id);
+ sprintf(CS big_buffer, "%.64s", client_authenticated_id);
while(*ptr++);
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'C', '2', big_buffer, ptr - big_buffer);
}
if (client_authenticated_sender)
{
ptr = big_buffer;
- sprintf(CS big_buffer, "C3%.64s", client_authenticated_sender);
+ sprintf(CS big_buffer, "%.64s", client_authenticated_sender);
while(*ptr++);
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'C', '3', big_buffer, ptr - big_buffer);
}
#ifndef DISABLE_PRDR
if (addr->flags & af_prdr_used)
- rmt_dlv_checked_write(fd, "P", 1);
-#endif
+ rmt_dlv_checked_write(fd, 'P', '0', NULL, 0);
+ #endif
-#ifdef EXPERIMENTAL_DSN
- big_buffer[0] = 'D';
- memcpy(big_buffer+1, &addr->dsn_aware, sizeof(addr->dsn_aware));
- rmt_dlv_checked_write(fd, big_buffer, sizeof(addr->dsn_aware) + 1);
+ #ifdef EXPERIMENTAL_DSN
+ memcpy(big_buffer, &addr->dsn_aware, sizeof(addr->dsn_aware));
+ rmt_dlv_checked_write(fd, 'D', '0', big_buffer, sizeof(addr->dsn_aware));
DEBUG(D_deliver) debug_printf("DSN write: addr->dsn_aware = %d\n", addr->dsn_aware);
#endif
@@ -4276,7 +4355,7 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
for (r = addr->retries; r != NULL; r = r->next)
{
uschar *ptr;
- sprintf(CS big_buffer, "R%c%.500s", r->flags, r->key);
+ sprintf(CS big_buffer, "%c%.500s", r->flags, r->key);
ptr = big_buffer + Ustrlen(big_buffer+2) + 3;
memcpy(ptr, &(r->basic_errno), sizeof(r->basic_errno));
ptr += sizeof(r->basic_errno);
@@ -4287,13 +4366,13 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
sprintf(CS ptr, "%.512s", r->message);
while(*ptr++);
}
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'R', '0', big_buffer, ptr - big_buffer);
}
/* The rest of the information goes in an 'A' item. */
- ptr = big_buffer + 3;
- sprintf(CS big_buffer, "A%c%c", addr->transport_return,
+ ptr = big_buffer + 2;
+ sprintf(CS big_buffer, "%c%c", addr->transport_return,
addr->special_action);
memcpy(ptr, &(addr->basic_errno), sizeof(addr->basic_errno));
ptr += sizeof(addr->basic_errno);
@@ -4328,7 +4407,7 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
: addr->host_used->dnssec==DS_NO ? '1' : '0';
}
- rmt_dlv_checked_write(fd, big_buffer, ptr - big_buffer);
+ rmt_dlv_checked_write(fd, 'A', '0', big_buffer, ptr - big_buffer);
}
/* Add termination flag, close the pipe, and that's it. The character
@@ -4336,9 +4415,8 @@ for (delivery_count = 0; addr_remote != NULL; delivery_count++)
A change from non-NULL to NULL indicates a problem with a continuing
connection. */
- big_buffer[0] = 'Z';
- big_buffer[1] = (continue_transport == NULL)? '0' : '1';
- rmt_dlv_checked_write(fd, big_buffer, 2);
+ big_buffer[0] = (continue_transport == NULL)? '0' : '1';
+ rmt_dlv_checked_write(fd, 'Z', '0', big_buffer, 1);
(void)close(fd);
exit(EXIT_SUCCESS);
}
diff --git a/src/src/macros.h b/src/src/macros.h
index b7dd337..d06e263 100644
--- a/src/src/macros.h
+++ b/src/src/macros.h
@@ -156,6 +156,10 @@ as long as the maximum path length. */
#define BIG_BUFFER_SIZE 16384
#endif
+/* header size of pipe content
+ currently: char id, char subid, char[5] length */
+#define PIPE_HEADER_SIZE 7
+
/* This limits the length of data returned by local_scan(). Because it is
written on the spool, it gets read into big_buffer. */
