On Wed, Apr 5, 2017 at 3:04 PM, Tom G. Christensen <t...@jupiterrise.com> wrote: > This adds an OLD_GNUPG define to the Makefile which when activated will > ensure git does not use the --keyid-format argument when calling the > 'gpg' program. > This is consistent with how 'gpg' was used in git < 2.10.0 and slightly > decreases security.
This changes the code Linus Torvalds added in b624a3e67f to mitigate the evil32 project generating keys which looked the same for 32 bit signatures. I think this change makes sense, but the Makefile should have a slightly scarier warning, something like: "Define OLD_GNUPG if you need support for gnupg <1.4. Note that this will cause git to only show the first 32 bits of PGP keys instead of 64, and there's a wide variety of brute-forced 32 bit keys in the wild thanks to the evil32 project (https://evil32.com). Enabling this will make GPG work old versions, but you might be fooled into accepting malicious keys as a result". > Signed-off-by: Tom G. Christensen <t...@jupiterrise.com> > --- > Makefile | 6 ++++++ > gpg-interface.c | 2 ++ > 2 files changed, 8 insertions(+) > > diff --git a/Makefile b/Makefile > index ca9f16d19..f8f585d21 100644 > --- a/Makefile > +++ b/Makefile > @@ -386,6 +386,8 @@ all:: > # > # to say "export LESS=FRX (and LV=-c) if the environment variable > # LESS (and LV) is not set, respectively". > +# > +# Define OLD_GNUPG if you need support for gnupg < 1.4. > > GIT-VERSION-FILE: FORCE > @$(SHELL_PATH) ./GIT-VERSION-GEN > @@ -1529,6 +1531,10 @@ ifndef PAGER_ENV > PAGER_ENV = LESS=FRX LV=-c > endif > > +ifdef OLD_GNUPG > + BASIC_CFLAGS += -DOLD_GNUPG > +endif > + > QUIET_SUBDIR0 = +$(MAKE) -C # space to separate -C and subdir > QUIET_SUBDIR1 = > > diff --git a/gpg-interface.c b/gpg-interface.c > index e44cc27da..57f1ea792 100644 > --- a/gpg-interface.c > +++ b/gpg-interface.c > @@ -224,7 +224,9 @@ int verify_signed_buffer(const char *payload, size_t > payload_size, > argv_array_pushl(&gpg.args, > gpg_program, > "--status-fd=1", > +#ifndef OLD_GNUPG > "--keyid-format=long", > +#endif > "--verify", temp.filename.buf, "-", > NULL); > > -- > 2.12.2 >
