diff options
Diffstat (limited to 'apt-pkg/contrib/gpgv.cc')
| -rw-r--r-- | apt-pkg/contrib/gpgv.cc | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/apt-pkg/contrib/gpgv.cc b/apt-pkg/contrib/gpgv.cc index 35d859849..d956eaf00 100644 --- a/apt-pkg/contrib/gpgv.cc +++ b/apt-pkg/contrib/gpgv.cc @@ -297,10 +297,24 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, } if (found_signatures == 0 && statusfd != -1) { - // This is not an attack attempt but a file even gpgv would complain about - // likely the result of a paywall which is covered by the gpgv method auto const errtag = "[GNUPG:] NODATA\n"; FileFd::Write(fd[1], errtag, strlen(errtag)); + // guess if this is a binary signature, we never officially supported them, + // but silently accepted them via passing them unchecked to gpgv + if (found_badcontent) + { + rewind(detached.get()); + auto ptag = fgetc(detached.get()); + // ยง4.2 says that the first bit is always set and gpg seems to generate + // only old format which is indicated by the second bit not set + if (ptag != EOF && (ptag & 0x80) != 0 && (ptag & 0x40) == 0) + { + apt_error(std::cerr, statusfd, fd, "Detached signature file '%s' is in unsupported binary format", FileGPG.c_str()); + local_exit(112); + } + } + // This is not an attack attempt but a file even gpgv would complain about + // likely the result of a paywall which is covered by the gpgv method local_exit(113); } else if (found_badcontent) |