damaged email
I have a gauntlet based firewall that is damaging emails (in a consistent manner) as they pass through.
The damage always occurs in the attachment which is encoded as printed quoteable.
Network sniffing captures of the SMTP traffic show the solaris box is inserting an extra "." into the
data stream.
This consistently happens in the email where a new line of SMTP text starts with "..06"
the damaged output looks like "...06"
Has anyone seen anything like this? Is there an approriate patch to sendmail for printed quotable
encodings?
Any information would be helpful.
[637 byte] By [
drodman] at [2007-11-25 23:23:38]
# 1
I hate it when I have some info on my own question but... A quote from RFC 821 seems to have some direct bearing: As I read this, it looks like EVERY SMTP relay should add a period to the start of text in my attachment. But when decoded, only the first period is removed. This describes my situtation completely, but doesn't hint at how to fix it.
4.5.2. TRANSPARENCY
Without some provision for data transparency the character
sequence "<CRLF>.<CRLF>" ends the mail text and cannot be sent
by the user. In general, users are not aware of such
"forbidden" sequences. To allow all user composed text to be
transmitted transparently the following procedures are used.
1. Before sending a line of mail text the sender-SMTP checks
the first character of the line. If it is a period, one
additional period is inserted at the beginning of the line.
2. When a line of mail text is received by the receiver-SMTP
it checks the line. If the line is composed of a single
period it is the end of mail. If the first character is a
period and there are other characters on the line, the first
character is deleted.
