mod_sysop: Enhance test email command.

Allow an optionally specified email address
to be the target of test emails.

Also ensure that when the original email
is attached to a delivery status notification,
it always ends in CR LF to prevent mangling
with the boundary.

modules/mod_sysop.c

@@ -122,8 +122,12 @@ static RWLIST_HEAD_STATIC(consoles, sysop_console);
 
 static int cli_testemail(struct bbs_cli_args *a)
 {
-	UNUSED(a);
-	return bbs_mail(0, NULL, NULL, NULL, "Test Email", "This is a test email.\r\n\t--LBBS");
+	const char *recipient = a->argc >= 2 ? a->argv[1] : NULL; /* Default to sysop */
+	return bbs_mail(0, recipient, NULL, NULL, "Test Email",
+		"This is a test message generated automatically by the LBBS bulletin board system.\r\n"
+		"You may be receiving this to test deliverability to your address after a previous delivery failure.\r\n"
+		"If you have any questions, please contact your sysop directly; please, do not respond to this message.\r\n"
+		"\t--LBBS\r\n"); /* Email should end with CR LF */
 }
 
 static int cli_mtrim(struct bbs_cli_args *a)
@@ -547,7 +551,7 @@ static int cli_consoles(struct bbs_cli_args *a)
 static struct bbs_cli_entry cli_commands_sysop[] = {
 	BBS_CLI_COMMAND(cli_consoles, "consoles", 1, "List all sysop console sessions", NULL),
 	/* General */
-	BBS_CLI_COMMAND(cli_testemail, "testemail", 1, "Send test email to sysop", NULL),
+	BBS_CLI_COMMAND(cli_testemail, "testemail", 1, "Send test email to a recipient (default: sysop)", "testemail <address>"),
 	BBS_CLI_COMMAND(cli_mtrim, "mtrim", 1, "Manually release free memory at the top of the heap", NULL),
 	BBS_CLI_COMMAND(cli_assert, "assert", 1, "Manually trigger an assertion (WARNING: May abort BBS)", NULL),
 	BBS_CLI_COMMAND(cli_copyright, "copyright", 1, "Show copyright notice", NULL),

nets/net_smtp.c

@@ -1479,10 +1479,10 @@ static int any_failures(struct smtp_delivery_outcome **f, int n)
 int smtp_dsn(const char *sendinghost, struct tm *arrival, const char *sender, int srcfd, int offset, size_t msglen, struct smtp_delivery_outcome **f, int n)
 {
 	int i, res;
-	char tmpattach[256] = "/tmp/bouncemsgXXXXXX";
+	char tmpattach[32] = "/tmp/bouncemsgXXXXXX";
 	FILE *fp;
 	char bound[256];
-	char date[256], date2[256];
+	char date[50], date2[50];
 	struct tm tm;
 	size_t length;
 	time_t t = time(NULL);
@@ -1502,7 +1502,10 @@ int smtp_dsn(const char *sendinghost, struct tm *arrival, const char *sender, in
 	/* Format of the non-delivery report is defined in RFC 3461 Section 6 */
 
 	/* Generate headers */
-	strftime(date, sizeof(date), "%a, %d %b %Y %H:%M:%S %z", localtime_r(&t, &tm));
+	if (!strftime(date, sizeof(date), "%a, %d %b %Y %H:%M:%S %z", localtime_r(&t, &tm))) {
+		bbs_error("strftime failed\n");
+		date[0] = '\0';
+	}
 	fprintf(fp, "Date: %s\r\n", date);
 	fprintf(fp, "From: \"Mail Delivery Subsystem\" <mailer-daemon@%s>\r\n", bbs_hostname());
 	fprintf(fp, "Subject: %s\r\n", delivery_subject_name(f, n));
@@ -1601,11 +1604,11 @@ int smtp_dsn(const char *sendinghost, struct tm *arrival, const char *sender, in
 		bbs_copy_file(srcfd, fileno(fp), offset, (int) msglen);
 
 		fseek(fp, 0, SEEK_END);
-		fprintf(fp, "--%s\r\n", bound);
 	}
 
 	fflush(fp);
-	fprintf(fp, "--%s--\r\n", bound); /* Last one, so include 2 dashes after the boundary */
+	/* Include CR LF first, in case original message did not end with one, to prevent boundary from leaking onto last line of attachment. */
+	fprintf(fp, "\r\n--%s--\r\n", bound); /* Last one, so include 2 dashes after the boundary */
 	length = (size_t) ftell(fp);
 	fclose(fp);