wmbiff - handle incorrect replies from office365.com IMAP server

[tnais]

This nice IMAP server authors could have violated (did not check correctly) the RFC that should state that multiple blanks in a reply are not allowed.

No matter if putting multiple blanks in an imap reply is or is not legal, I prefer to patch my code to have wmbiff working. My solution was to replace strncpy with a replacement that copies a single blank each time multiple blanks are found.

Having issues committing the single changed file (dockapps/wmbiff/wmbiff/tlsComm.c I add my patch here.

---------------------------------------8<----------------------------------------------------------------------
From 1697c7f78874e66ac25f4249805f111fecc9ba18 Mon Sep 17 00:00:00 2001
Message-Id: 1697c7f78874e66ac25f4249805f111fecc9ba18.1679925131.git.saint@eng.it
In-Reply-To: f2bf4066c333a526d2f87733edb342acde7e466d.1679925131.git.saint@eng.it
References: f2bf4066c333a526d2f87733edb342acde7e466d.1679925131.git.saint@eng.it
From: Gian Uberto Lauri saint@eng.it
Date: Mon, 27 Mar 2023 15:40:56 +0200
Subject: [PATCH 2/2] #feature/handle_multiple_blanks - Handles wrong
(multiple blanks) answer from Office365 IMAP server

Changes to be committed:
modified: wmbiff/wmbiff/tlsComm.c

wmbiff/wmbiff/tlsComm.c | 31 ++++++++++++++++++++++++++++++-
1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/wmbiff/wmbiff/tlsComm.c b/wmbiff/wmbiff/tlsComm.c
index 03b8009..fb4731a 100644
--- a/wmbiff/wmbiff/tlsComm.c
+++ b/wmbiff/wmbiff/tlsComm.c
@@ -159,6 +159,35 @@ static int wait_for_it(int sd, int timeoutseconds)
return (FD_ISSET(sd, &readfds));
}

+/* exported for testing /
+/ This version converts sequence of multiple blanks into a single

• • blank. This overcomes, say, the bug in the imap server of a random
• • company who thinks it can disregard standards because it is big and
• • hard. (pun intended) */
    +extern char *
    +strncpy_trim_blanks(char *dest, const char *src, size_t n)
    +{
• size_t i;

•   int last_read_was_not_a_blank = 1;
  

•   char *m_src = src, *m_dest = dest;
  

•   char ch;
  

•   for (i = 0; i < n && src[i] != '\0'; i++) {
  

•   		ch = *m_src++;
  

•   		if (ch != ' ' || last_read_was_not_a_blank) {
  

•   				*m_dest = ch;
  

•   				m_dest++;
  

•   		}
  

•   		last_read_was_not_a_blank = ch != ' ';
  

•   }
  

• for ( ; i < n; i++)

•    dest[i] = '\0';
  

•   return dest;
  

+}
+
/* exported for testing */
extern int
getline_from_buffer(char *readbuffer, char *linebuffer, int linebuflen)
@@ -184,7 +213,7 @@ getline_from_buffer(char *readbuffer, char *linebuffer, int linebuflen)

if (i != 0) {
	/* copy a line into the linebuffer */

•   strncpy(linebuffer, readbuffer, (size_t) i);
  

•   strncpy_trim_blanks(linebuffer, readbuffer, (size_t) i);
    /* sigh, null terminate */
    linebuffer[i] = '\0';
    /* shift the rest over; this could be done
  

--
2.37.2

-------8<------------------------------------------------------------------------------------