static void smtp_quit_handler(uschar **, uschar **);
static void smtp_rset_handler(void);
-/*************************************************
-* Recheck synchronization *
-*************************************************/
-
-/* Synchronization checks can never be perfect because a packet may be on its
-way but not arrived when the check is done. Normally, the checks happen when
-commands are read: Exim ensures that there is no more input in the input buffer.
-In normal cases, the response to the command will be fast, and there is no
-further check.
-
-However, for some commands an ACL is run, and that can include delays. In those
-cases, it is useful to do another check on the input just before sending the
-response. This also applies at the start of a connection. This function does
-that check by means of the select() function, as long as the facility is not
-disabled or inappropriate. A failure of select() is ignored.
-
-When there is unwanted input, we read it so that it appears in the log of the
-error.
-
-Arguments: none
-Returns: TRUE if all is well; FALSE if there is input pending
-*/
-
-static BOOL
-wouldblock_reading(void)
-{
-int fd, rc;
-
-#ifndef DISABLE_TLS
-if (tls_in.active.sock >= 0)
- return !tls_could_read();
-#endif
-
-if (smtp_inptr < smtp_inend)
- return FALSE;
-
-fd = fileno(smtp_in);
-rc = poll_one_fd(fd, POLLIN, 0);
-
-if (rc <= 0) return TRUE; /* Not ready to read */
-rc = smtp_getc(GETC_BUFFER_UNLIMITED);
-if (rc < 0) return TRUE; /* End of file or error */
-
-smtp_ungetc(rc);
-return FALSE;
-}
-
-static BOOL
-check_sync(void)
-{
-if (!smtp_enforce_sync || !sender_host_address || f.sender_host_notsocket)
- return TRUE;
-
-return wouldblock_reading();
-}
-
-
-/* If there's input waiting (and we're doing pipelineing) then we can pipeline
-a reponse with the one following. */
-
-static BOOL
-pipeline_response(void)
-{
-if ( !smtp_enforce_sync || !sender_host_address
- || f.sender_host_notsocket || !f.smtp_in_pipelining_advertised)
- return FALSE;
-
-if (wouldblock_reading()) return FALSE;
-f.smtp_in_pipelining_used = TRUE;
-return TRUE;
-}
-
-
-#ifndef DISABLE_PIPE_CONNECT
-static BOOL
-pipeline_connect_sends(void)
-{
-if (!sender_host_address || f.sender_host_notsocket || !fl.pipe_connect_acceptable)
- return FALSE;
-
-if (wouldblock_reading()) return FALSE;
-f.smtp_in_early_pipe_used = TRUE;
-return TRUE;
-}
-#endif
-
/*************************************************
* Log incomplete transactions *
*************************************************/
}
+/******************************************************************************/
+/* SMTP input buffer handling. Most of these are similar to stdio routines. */
+
+static void
+smtp_buf_init(void)
+{
+/* Set up the buffer for inputting using direct read() calls, and arrange to
+call the local functions instead of the standard C ones. Place a NUL at the
+end of the buffer to safety-stop C-string reads from it. */
+
+if (!(smtp_inbuffer = US malloc(IN_BUFFER_SIZE)))
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer");
+smtp_inbuffer[IN_BUFFER_SIZE-1] = '\0';
+
+smtp_inptr = smtp_inend = smtp_inbuffer;
+smtp_had_eof = smtp_had_error = 0;
+}
+
+
/* Refill the buffer, and notify DKIM verification code.
Return false for error or EOF.
smtp_refill(unsigned lim)
{
int rc, save_errno;
+
if (!smtp_out) return FALSE;
fflush(smtp_out);
if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
return TRUE;
}
-/*************************************************
-* SMTP version of getc() *
-*************************************************/
-/* This gets the next byte from the SMTP input buffer. If the buffer is empty,
+/* Check if there is buffered data */
+
+BOOL
+smtp_hasc(void)
+{
+return smtp_inptr < smtp_inend;
+}
+
+/* SMTP version of getc()
+
+This gets the next byte from the SMTP input buffer. If the buffer is empty,
it flushes the output, and refills the buffer, with a timeout. The signal
handler is set appropriately by the calling function. This function is not used
after a connection has negotiated itself into an TLS/SSL state.
int
smtp_getc(unsigned lim)
{
-if (smtp_inptr >= smtp_inend)
- if (!smtp_refill(lim))
- return EOF;
+if (!smtp_hasc() && !smtp_refill(lim)) return EOF;
return *smtp_inptr++;
}
-BOOL
-smtp_hasc(void)
-{
-return smtp_inptr < smtp_inend;
-}
+/* Get many bytes, refilling buffer if needed */
uschar *
smtp_getbuf(unsigned * len)
unsigned size;
uschar * buf;
-if (smtp_inptr >= smtp_inend)
- if (!smtp_refill(*len))
- { *len = 0; return NULL; }
+if (!smtp_hasc() && !smtp_refill(*len))
+ { *len = 0; return NULL; }
if ((size = smtp_inend - smtp_inptr) > *len) size = *len;
buf = smtp_inptr;
return buf;
}
+/* Copy buffered data to the dkim feed.
+Called, unless TLS, just before starting to read message headers. */
+
void
smtp_get_cache(unsigned lim)
{
}
+/* SMTP version of ungetc()
+Puts a character back in the input buffer. Only ever called once.
+
+Arguments:
+ ch the character
+
+Returns: the character
+*/
+
+int
+smtp_ungetc(int ch)
+{
+if (smtp_inptr <= smtp_inbuffer) /* NB: NOT smtp_hasc() ! */
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "buffer underflow in smtp_ungetc");
+
+*--smtp_inptr = ch;
+return ch;
+}
+
+
+/* SMTP version of feof()
+Tests for a previous EOF
+
+Arguments: none
+Returns: non-zero if the eof flag is set
+*/
+
+int
+smtp_feof(void)
+{
+return smtp_had_eof;
+}
+
+
+/* SMTP version of ferror()
+Tests for a previous read error, and returns with errno
+restored to what it was when the error was detected.
+
+Arguments: none
+Returns: non-zero if the error flag is set
+*/
+
+int
+smtp_ferror(void)
+{
+errno = smtp_had_error;
+return smtp_had_error;
+}
+
+
+/* Check if a getc will block or not */
+
+static BOOL
+smtp_could_getc(void)
+{
+int fd, rc;
+fd_set fds;
+struct timeval tzero = {.tv_sec = 0, .tv_usec = 0};
+
+if (smtp_inptr < smtp_inend)
+ return TRUE;
+
+fd = fileno(smtp_in);
+FD_ZERO(&fds);
+FD_SET(fd, &fds);
+rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero);
+
+if (rc <= 0) return FALSE; /* Not ready to read */
+rc = smtp_getc(GETC_BUFFER_UNLIMITED);
+if (rc < 0) return FALSE; /* End of file or error */
+
+smtp_ungetc(rc);
+return TRUE;
+}
+
+
+/******************************************************************************/
+/*************************************************
+* Recheck synchronization *
+*************************************************/
+
+/* Synchronization checks can never be perfect because a packet may be on its
+way but not arrived when the check is done. Normally, the checks happen when
+commands are read: Exim ensures that there is no more input in the input buffer.
+In normal cases, the response to the command will be fast, and there is no
+further check.
+
+However, for some commands an ACL is run, and that can include delays. In those
+cases, it is useful to do another check on the input just before sending the
+response. This also applies at the start of a connection. This function does
+that check by means of the select() function, as long as the facility is not
+disabled or inappropriate. A failure of select() is ignored.
+
+When there is unwanted input, we read it so that it appears in the log of the
+error.
+
+Arguments: none
+Returns: TRUE if all is well; FALSE if there is input pending
+*/
+
+static BOOL
+wouldblock_reading(void)
+{
+#ifndef DISABLE_TLS
+if (tls_in.active.sock >= 0)
+ return !tls_could_getc();
+#endif
+
+return !smtp_could_getc();
+}
+
+static BOOL
+check_sync(void)
+{
+if (!smtp_enforce_sync || !sender_host_address || f.sender_host_notsocket)
+ return TRUE;
+
+return wouldblock_reading();
+}
+
+
+/******************************************************************************/
+/* Variants of the smtp_* input handling functions for use in CHUNKING mode */
+
/* Forward declarations */
static inline void bdat_push_receive_functions(void);
static inline void bdat_pop_receive_functions(void);
lwr_receive_ungetc = NULL;
}
-/*************************************************
-* SMTP version of ungetc() *
-*************************************************/
-
-/* Puts a character back in the input buffer. Only ever
-called once.
-
-Arguments:
- ch the character
-
-Returns: the character
-*/
-
-int
-smtp_ungetc(int ch)
-{
-if (smtp_inptr <= smtp_inbuffer)
- log_write(0, LOG_MAIN|LOG_PANIC_DIE, "buffer underflow in smtp_ungetc");
-
-*--smtp_inptr = ch;
-return ch;
-}
-
-
int
bdat_ungetc(int ch)
{
-/*************************************************
-* SMTP version of feof() *
-*************************************************/
-
-/* Tests for a previous EOF
-
-Arguments: none
-Returns: non-zero if the eof flag is set
-*/
-
-int
-smtp_feof(void)
-{
-return smtp_had_eof;
-}
-
-
-
-
-/*************************************************
-* SMTP version of ferror() *
-*************************************************/
-
-/* Tests for a previous read error, and returns with errno
-restored to what it was when the error was detected.
-
-Arguments: none
-Returns: non-zero if the error flag is set
-*/
-
-int
-smtp_ferror(void)
-{
-errno = smtp_had_error;
-return smtp_had_error;
-}
-
-
-
-/*************************************************
-* Test for characters in the SMTP buffer *
-*************************************************/
-
-/* Used at the end of a message
-
-Arguments: none
-Returns: TRUE/FALSE
-*/
-
-BOOL
-smtp_buffered(void)
-{
-return smtp_inptr < smtp_inend;
-}
-
-
+/******************************************************************************/
/*************************************************
* Write formatted string to SMTP channel *
+/* If there's input waiting (and we're doing pipelineing) then we can pipeline
+a reponse with the one following. */
+
+static BOOL
+pipeline_response(void)
+{
+if ( !smtp_enforce_sync || !sender_host_address
+ || f.sender_host_notsocket || !f.smtp_in_pipelining_advertised)
+ return FALSE;
+
+if (wouldblock_reading()) return FALSE;
+f.smtp_in_pipelining_used = TRUE;
+return TRUE;
+}
+
+
+#ifndef DISABLE_PIPE_CONNECT
+static BOOL
+pipeline_connect_sends(void)
+{
+if (!sender_host_address || f.sender_host_notsocket || !fl.pipe_connect_acceptable)
+ return FALSE;
+
+if (wouldblock_reading()) return FALSE;
+f.smtp_in_early_pipe_used = TRUE;
+return TRUE;
+}
+#endif
+
/*************************************************
* SMTP command read timeout *
*************************************************/
|| smtp_cmd_buffer[p->len] == ' '
) )
{
- if (smtp_inptr < smtp_inend && /* Outstanding input */
- p->cmd < sync_cmd_limit && /* Command should sync */
- check_sync && /* Local flag set */
- smtp_enforce_sync && /* Global flag set */
- sender_host_address != NULL && /* Not local input */
- !f.sender_host_notsocket) /* Really is a socket */
+ if ( smtp_inptr < smtp_inend /* Outstanding input */
+ && p->cmd < sync_cmd_limit /* Command should sync */
+ && check_sync /* Local flag set */
+ && smtp_enforce_sync /* Global flag set */
+ && sender_host_address != NULL /* Not local input */
+ && !f.sender_host_notsocket /* Really is a socket */
+ )
return BADSYN_CMD;
/* The variables $smtp_command and $smtp_command_argument point into the
&& check_sync /* Local flag set */
&& smtp_enforce_sync /* Global flag set */
&& sender_host_address /* Not local input */
- && !f.sender_host_notsocket) /* Really is a socket */
+ && !f.sender_host_notsocket /* Really is a socket */
+ )
return BADSYN_CMD;
return OTHER_CMD;
(sender_host_address ? protocols : protocols_local) [pnormal];
/* Set up the buffer for inputting using direct read() calls, and arrange to
-call the local functions instead of the standard C ones. Place a NUL at the
-end of the buffer to safety-stop C-string reads from it. */
+call the local functions instead of the standard C ones. */
-if (!(smtp_inbuffer = US malloc(IN_BUFFER_SIZE)))
- log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer");
-smtp_inbuffer[IN_BUFFER_SIZE-1] = '\0';
+smtp_buf_init();
receive_getc = smtp_getc;
receive_getbuf = smtp_getbuf;
receive_ungetc = smtp_ungetc;
receive_feof = smtp_feof;
receive_ferror = smtp_ferror;
-receive_smtp_buffered = smtp_buffered;
lwr_receive_getc = NULL;
lwr_receive_getbuf = NULL;
lwr_receive_hasc = NULL;
lwr_receive_ungetc = NULL;
-smtp_inptr = smtp_inend = smtp_inbuffer;
-smtp_had_eof = smtp_had_error = 0;
/* Set up the message size limit; this may be host-specific */
Pipelining sync checks will normally have protected us too, unless disabled
by configuration. */
- if (receive_smtp_buffered())
+ if (receive_hasc())
{
DEBUG(D_any)
debug_printf("Non-empty input buffer after STARTTLS; naive attack?\n");
git://git.exim.org / exim.git / blobdiff