postfix-3.9-20231226

postfix/HISTORY

@@ -27644,17 +27644,11 @@ Apologies for any names omitted.
 	mantools/postlink, proto/postconf.proto, global/mail_params.h,
 	global/smtp_stream.c, global/smtp_stream.h, smtpd/smtpd.c.
 
-20231222
+20231226
 
-	Workaround: smtpd_forbid_bare_newline broke the BDAT command.
+	Cleanup: a nicer implementation of smtpd_forbid_bare_newline
-	File: smtpd/smtpd.c.
+	that does not hang up the the middle of a BDAT or DATA
-
+	command, and that optionally includes the offending command
-20231123
+	sequence in a postmaster 'protocol' notification. Files:
-
+	smtpd/smtpd.c, global/stp_stream.[hc], global/cleanup_user.h,
-	Bugfix: smtpd_forbid_bare_newline_exclusions should respect
+	global/cleanup_strerror.c.
-	XCLIENT overrides. File: smtpd/smtpd.c.
-
-20231224
-
-	Reverted change 20231221 and adopted a fix by Viktor. File:
-	smtpd/smtpd.c.

postfix/src/global/cleanup_strerror.c

@@ -73,6 +73,7 @@ static const CLEANUP_STAT_DETAIL cleanup_stat_map[] = {
     CLEANUP_STAT_CONT, 550, "5.7.1", "message content rejected",
     CLEANUP_STAT_WRITE, 451, "4.3.0", "queue file write error",
     CLEANUP_STAT_NOPERM, 550, "5.7.1", "service denied",
+    CLEANUP_STAT_BARE_LF, 521, "5.5.2", "bare <LF> received",
 };
 
 static CLEANUP_STAT_DETAIL cleanup_stat_success = {

postfix/src/global/cleanup_user.h

@@ -64,6 +64,12 @@
 #define CLEANUP_STAT_DEFER	(1<<8)	/* Temporary reject */
 #define CLEANUP_STAT_NOPERM	(1<<9)	/* Denied by non-content policy */
 
+ /*
+  * Non-cleanup errors that live in the same bitmask space, to centralize
+  * error handling.
+  */
+#define CLEANUP_STAT_BARE_LF	(1<<16)	/* Bare <LF> received */
+
  /*
   * These are set when we can't bounce even if we were asked to.
   */

postfix/src/global/mail_version.h

@@ -20,7 +20,7 @@
   * Patches change both the patchlevel and the release date. Snapshots have no
   * patchlevel; they change the release date only.
   */
-#define MAIL_RELEASE_DATE	"20231224"
+#define MAIL_RELEASE_DATE	"20231226"
 #define MAIL_VERSION_NUMBER	"3.9"
 
 #ifdef SNAPSHOT

postfix/src/global/smtp_stream.c

@@ -54,6 +54,7 @@
 /*	va_list	ap;
 /*
 /*	int	smtp_forbid_bare_lf;
+/*	int	smtp_seen_bare_lf;
 /* AUXILIARY API
 /*	int	smtp_get_noexcept(vp, stream, maxlen, flags)
 /*	VSTRING	*vp;
@@ -133,16 +134,17 @@
 /*	smtp_vprintf() is the machine underneath smtp_printf().
 /*
 /*	smtp_get_noexcept() implements the subset of smtp_get()
-/*	without long jumps for timeout or EOF errors. Instead,
+/*	without timeouts and without making long jumps. Instead
 /*	query the stream status with vstream_feof() etc.
-/*	This function will make a VSTREAM long jump (error code
+/*	This function will set smtp_forbid_bare_lf when flagging
-/*	SMTP_ERR_LF) when rejecting input with a bare newline byte.
+/*	input with a bare newline byte.
 /*
 /*	smtp_timeout_setup() is a backwards-compatibility interface
 /*	for programs that don't require deadline or data-rate support.
 /*
 /*	smtp_forbid_bare_lf controls whether smtp_get_noexcept()
-/*	will reject input with a bare newline byte.
+/*	will set smtp_seen_bare_lf when the line that was read last
+/*	ended with a bare newline byte.
 /* DIAGNOSTICS
 /* .fi
 /* .ad
@@ -222,6 +224,7 @@
   * body content one line at a time.
   */
 int     smtp_forbid_bare_lf;
+int     smtp_seen_bare_lf;
 
 /* smtp_timeout_reset - reset per-stream error flags */
 
@@ -384,6 +387,8 @@ int     smtp_get_noexcept(VSTRING *vp, VSTREAM *stream, ssize_t bound, int flags
     int     last_char;
     int     next_char;
 
+    smtp_seen_bare_lf = 0;
+
     /*
      * It's painful to do I/O with records that may span multiple buffers.
      * Allow for partial long lines (we will read the remainder later) and
@@ -428,7 +433,7 @@ int     smtp_get_noexcept(VSTRING *vp, VSTREAM *stream, ssize_t bound, int flags
 	vstring_truncate(vp, VSTRING_LEN(vp) - 1);
 	if (smtp_forbid_bare_lf
 	    && (VSTRING_LEN(vp) == 0 || vstring_end(vp)[-1] != '\r'))
-	    vstream_longjmp(stream, SMTP_ERR_LF);
+	    smtp_seen_bare_lf = 1;
 	while (VSTRING_LEN(vp) > 0 && vstring_end(vp)[-1] == '\r')
 	    vstring_truncate(vp, VSTRING_LEN(vp) - 1);
 	VSTRING_TERMINATE(vp);

postfix/src/global/smtp_stream.h

@@ -32,7 +32,6 @@
 #define SMTP_ERR_QUIET	3		/* silent cleanup (application) */
 #define SMTP_ERR_NONE	4		/* non-error case */
 #define SMTP_ERR_DATA	5		/* application data error */
-#define SMTP_ERR_LF	6		/* bare <LF> protocol error */
 
 extern void smtp_stream_setup(VSTREAM *, int, int, int);
 extern void PRINTFLIKE(2, 3) smtp_printf(VSTREAM *, const char *,...);
@@ -45,6 +44,7 @@ extern void smtp_fwrite(const char *, ssize_t len, VSTREAM *);
 extern void smtp_fread_buf(VSTRING *, ssize_t len, VSTREAM *);
 extern void smtp_fputc(int, VSTREAM *);
 extern int smtp_forbid_bare_lf;
+extern int smtp_seen_bare_lf;
 
 extern void smtp_vprintf(VSTREAM *, const char *, va_list);
 

postfix/src/smtpd/smtpd.c

@@ -1620,7 +1620,6 @@ static void tls_reset(SMTPD_STATE *);
 #define REASON_TIMEOUT		"timeout"
 #define REASON_LOST_CONNECTION	"lost connection"
 #define REASON_ERROR_LIMIT	"too many errors"
-#define REASON_BARE_LF		"bare <LF> received"
 
 #ifdef USE_TLS
 
@@ -3625,6 +3624,8 @@ static void receive_data_message(SMTPD_STATE *state,
 	    curr_rec_type = REC_TYPE_NORM;
 	else
 	    curr_rec_type = REC_TYPE_CONT;
+	if (smtp_seen_bare_lf)
+	    state->err |= CLEANUP_STAT_BARE_LF;
 	start = vstring_str(state->buffer);
 	len = VSTRING_LEN(state->buffer);
 	if (first) {
@@ -3792,6 +3793,12 @@ static int common_post_message_handling(SMTPD_STATE *state)
 	else
 	    smtpd_chat_reply(state,
 			     "250 2.0.0 Ok: queued as %s", state->queue_id);
+    } else if ((state->err & CLEANUP_STAT_BARE_LF) != 0) {
+	/* Disconnect immediately. */
+	state->error_mask |= MAIL_ERROR_PROTOCOL;
+	msg_info("disconnect: bare <LF> received from %s", state->namaddr);
+	smtpd_chat_reply(state, "521 5.5.2 %s Error: bare <LF> received",
+			 var_myhostname);
     } else if (why && IS_SMTP_REJECT(STR(why))) {
 	state->error_mask |= MAIL_ERROR_POLICY;
 	smtpd_chat_reply(state, "%s", STR(why));
@@ -4079,7 +4086,6 @@ static int bdat_cmd(SMTPD_STATE *state, int argc, SMTPD_TOKEN *argv)
      */
     done = 0;
     do {
-	int     payload_err;
 
 	/*
 	 * Do not skip the smtp_fread_buf() call if read_len == 0. We still
@@ -4093,10 +4099,6 @@ static int bdat_cmd(SMTPD_STATE *state, int argc, SMTPD_TOKEN *argv)
 	smtp_fread_buf(state->buffer, read_len, state->client);
 	state->bdat_get_stream = vstream_memreopen(
 			   state->bdat_get_stream, state->buffer, O_RDONLY);
-        vstream_control(state->bdat_get_stream, CA_VSTREAM_CTL_EXCEPT,
-                        CA_VSTREAM_CTL_END);
-        if ((payload_err = vstream_setjmp(state->bdat_get_stream)) != 0)
-            vstream_longjmp(state->client, payload_err);
 
 	/*
 	 * Read lines from the fragment. The last line may continue in the
@@ -4104,9 +4106,9 @@ static int bdat_cmd(SMTPD_STATE *state, int argc, SMTPD_TOKEN *argv)
 	 */
 	do {
 	    if (smtp_get_noexcept(state->bdat_get_buffer,
-                                     state->bdat_get_stream,
+				  state->bdat_get_stream,
-                                     var_line_limit,
+				  var_line_limit,
-                                     SMTP_GET_FLAG_APPEND) == '\n') {
+				  SMTP_GET_FLAG_APPEND) == '\n') {
 		/* Stopped at end-of-line. */
 		curr_rec_type = REC_TYPE_NORM;
 	    } else if (!vstream_feof(state->bdat_get_stream)) {
@@ -4121,6 +4123,8 @@ static int bdat_cmd(SMTPD_STATE *state, int argc, SMTPD_TOKEN *argv)
 		/* Skip the out_record() and VSTRING_RESET() calls below. */
 		break;
 	    }
+	    if (smtp_seen_bare_lf)
+		state->err |= CLEANUP_STAT_BARE_LF;
 	    start = vstring_str(state->bdat_get_buffer);
 	    len = VSTRING_LEN(state->bdat_get_buffer);
 	    if (state->err == CLEANUP_STAT_OK) {
@@ -5597,13 +5601,6 @@ static void smtpd_proto(SMTPD_STATE *state)
 			     var_myhostname);
 	break;
 
-    case SMTP_ERR_LF:
-	state->reason = REASON_BARE_LF;
-	if (vstream_setjmp(state->client) == 0)
-	    smtpd_chat_reply(state, "521 5.5.2 %s Error: bare <LF> received",
-			     var_myhostname);
-	break;
-
     case 0:
 
 	/*
@@ -5823,6 +5820,15 @@ static void smtpd_proto(SMTPD_STATE *state)
 	    }
 	    watchdog_pat();
 	    smtpd_chat_query(state);
+	    if (smtp_seen_bare_lf) {
+		msg_info("disconnect: bare <LF> received from %s",
+			 state->namaddr);
+		state->error_mask |= MAIL_ERROR_PROTOCOL;
+		smtpd_chat_reply(state,
+				 "521 5.5.2 %s Error: bare <LF> received",
+				 var_myhostname);
+		break;
+	    }
 	    /* Safety: protect internal interfaces against malformed UTF-8. */
 	    if (var_smtputf8_enable
 		&& valid_utf8_stringz(STR(state->buffer)) == 0) {