diff options
Diffstat (limited to 'doc/gpg.texi')
-rw-r--r-- | doc/gpg.texi | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/doc/gpg.texi b/doc/gpg.texi index 49a708a3e..260b9f33e 100644 --- a/doc/gpg.texi +++ b/doc/gpg.texi @@ -2580,17 +2580,13 @@ is the default. These options are obsolete and have no effect since GnuPG 2.1. @item --force-mdc +@itemx --disable-mdc @opindex force-mdc -Force the use of encryption with a modification detection code. This -is always used with the newer ciphers (those with a blocksize greater -than 64 bits), or if all of the recipient keys indicate MDC support in -their feature flags. - -@item --disable-mdc @opindex disable-mdc -Disable the use of the modification detection code. Note that by -using this option, the encrypted message becomes vulnerable to a -message modification attack. +These options are obsolete and have no effect since GnuPG 2.2.8. The +MDC is always used. But note: If the creation of a legacy non-MDC +message is exceptionally required, the option @option{--rfc2440} +allows for this. @item --disable-signer-uid @opindex disable-signer-uid @@ -2710,7 +2706,10 @@ keys or data may not be usable with future GnuPG versions. @item --rfc2440 @opindex rfc2440 Reset all packet, cipher and digest options to strict RFC-2440 -behavior. +behavior. Note that by using this option encryption packets are +created in a legacy mode without MDC protection. This is dangerous +and should thus only be used for experiments. See also option +@option{--ignore-mdc-error}. @item --pgp6 @opindex pgp6 @@ -2721,7 +2720,7 @@ compression algorithms none and ZIP. This also disables @option{--throw-keyids}, and making signatures with signing subkeys as PGP 6 does not understand signatures made by signing subkeys. -This option implies @option{--disable-mdc --escape-from-lines}. +This option implies @option{--escape-from-lines}. @item --pgp7 @opindex pgp7 @@ -3186,7 +3185,7 @@ It is required to decrypt old messages which did not use an MDC. It may also be useful if a message is partially garbled, but it is necessary to get as much data as possible out of that garbled message. Be aware that a missing or failed MDC can be an indication of an -attack. Use with caution. +attack. Use with great caution; see also option @option{--rfc2440}. @item --allow-weak-digest-algos @opindex allow-weak-digest-algos |