X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/76a71a1237d22c1990efbc19ce0e02aacf572576..91414dd77ec7efe1d3fc053e32cbe4d82263e015:/methods/gpgv.cc diff --git a/methods/gpgv.cc b/methods/gpgv.cc index 5800a04f0..60a7d4719 100644 --- a/methods/gpgv.cc +++ b/methods/gpgv.cc @@ -17,7 +17,10 @@ #include #include +#include #include +#include +#include #include #include #include @@ -37,6 +40,62 @@ using std::vector; #define GNUPGREVKEYSIG "[GNUPG:] REVKEYSIG" #define GNUPGNODATA "[GNUPG:] NODATA" +struct Digest { + enum class State { + Untrusted, + Weak, + Trusted, + } state; + char name[32]; + + State getState() const { + std::string optionUntrusted; + std::string optionWeak; + strprintf(optionUntrusted, "APT::Hashes::%s::Untrusted", name); + strprintf(optionWeak, "APT::Hashes::%s::Weak", name); + if (_config->FindB(optionUntrusted, state == State::Untrusted) == true) + return State::Untrusted; + if (_config->FindB(optionWeak, state == State::Weak) == true) + return State::Weak; + + return state; + } +}; + +static constexpr Digest Digests[] = { + {Digest::State::Untrusted, "Invalid digest"}, + {Digest::State::Untrusted, "MD5"}, + {Digest::State::Weak, "SHA1"}, + {Digest::State::Weak, "RIPE-MD/160"}, + {Digest::State::Trusted, "Reserved digest"}, + {Digest::State::Trusted, "Reserved digest"}, + {Digest::State::Trusted, "Reserved digest"}, + {Digest::State::Trusted, "Reserved digest"}, + {Digest::State::Trusted, "SHA256"}, + {Digest::State::Trusted, "SHA384"}, + {Digest::State::Trusted, "SHA512"}, + {Digest::State::Trusted, "SHA224"}, +}; + +static Digest FindDigest(std::string const & Digest) +{ + int id = atoi(Digest.c_str()); + if (id >= 0 && static_cast(id) < _count(Digests)) { + return Digests[id]; + } else { + return Digests[0]; + } +} + +struct Signer { + std::string key; + std::string note; +}; +static bool IsTheSameKey(std::string const &validsig, std::string const &goodsig) { + // VALIDSIG reports a keyid (40 = 24 + 16), GOODSIG is a longid (16) only + return validsig.compare(24, 16, goodsig, strlen("GOODSIG "), 16) == 0; +} + class GPGVMethod : public aptMethod { private: @@ -45,12 +104,11 @@ class GPGVMethod : public aptMethod vector &GoodSigners, vector &BadSigners, vector &WorthlessSigners, + vector &SoonWorthlessSigners, vector &NoPubKeySigners); - protected: virtual bool URIAcquire(std::string const &Message, FetchItem *Itm) APT_OVERRIDE; public: - GPGVMethod() : aptMethod("gpgv","1.0",SingleInstance | SendConfig) {}; }; @@ -59,6 +117,7 @@ string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile, vector &GoodSigners, vector &BadSigners, vector &WorthlessSigners, + vector &SoonWorthlessSigners, vector &NoPubKeySigners) { bool const Debug = _config->FindB("Debug::Acquire::gpgv", false); @@ -83,6 +142,7 @@ string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile, // Loop over the output of apt-key (which really is gnupg), and check the signatures. std::vector ValidSigners; + std::vector ErrSigners; size_t buffersize = 0; char *buffer = NULL; while (1) @@ -105,14 +165,16 @@ string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile, else if (strncmp(buffer, GNUPGERRSIG, sizeof(GNUPGERRSIG)-1) == 0) { if (Debug == true) - std::clog << "Got ERRSIG! " << std::endl; - BadSigners.push_back(string(buffer+sizeof(GNUPGPREFIX))); + std::clog << "Got ERRSIG " << std::endl; + ErrSigners.push_back(string(buffer, strlen(GNUPGPREFIX), strlen("ERRSIG ") + 16)); } else if (strncmp(buffer, GNUPGNOPUBKEY, sizeof(GNUPGNOPUBKEY)-1) == 0) { if (Debug == true) std::clog << "Got NO_PUBKEY " << std::endl; NoPubKeySigners.push_back(string(buffer+sizeof(GNUPGPREFIX))); + ErrSigners.erase(std::remove_if(ErrSigners.begin(), ErrSigners.end(), [&](std::string const &errsig) { + return errsig.compare(strlen("ERRSIG "), 16, buffer, strlen(GNUPGNOPUBKEY), 16) == 0; }), ErrSigners.end()); } else if (strncmp(buffer, GNUPGNODATA, sizeof(GNUPGBADSIG)-1) == 0) { @@ -146,17 +208,45 @@ string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile, else if (strncmp(buffer, GNUPGVALIDSIG, sizeof(GNUPGVALIDSIG)-1) == 0) { char *sig = buffer + sizeof(GNUPGVALIDSIG); + std::istringstream iss((string(sig))); + vector tokens{std::istream_iterator{iss}, + std::istream_iterator{}}; char *p = sig; while (*p && isxdigit(*p)) p++; *p = 0; - if (Debug == true) - std::clog << "Got VALIDSIG, key ID: " << sig << std::endl; + // Reject weak digest algorithms + Digest digest = FindDigest(tokens[7]); + switch (digest.getState()) { + case Digest::State::Weak: + // Treat them like an expired key: For that a message about expiry + // is emitted, a VALIDSIG, but no GOODSIG. + SoonWorthlessSigners.push_back({string(sig), digest.name}); + if (Debug == true) + std::clog << "Got weak VALIDSIG, key ID: " << sig << std::endl; + break; + case Digest::State::Untrusted: + // Treat them like an expired key: For that a message about expiry + // is emitted, a VALIDSIG, but no GOODSIG. + WorthlessSigners.push_back(string(sig)); + GoodSigners.erase(std::remove_if(GoodSigners.begin(), GoodSigners.end(), [&](std::string const &goodsig) { + return IsTheSameKey(string(sig), goodsig); }), GoodSigners.end()); + if (Debug == true) + std::clog << "Got untrusted VALIDSIG, key ID: " << sig << std::endl; + break; + + case Digest::State::Trusted: + if (Debug == true) + std::clog << "Got trusted VALIDSIG, key ID: " << sig << std::endl; + break; + } + ValidSigners.push_back(string(sig)); } } fclose(pipein); free(buffer); + std::move(ErrSigners.begin(), ErrSigners.end(), std::back_inserter(WorthlessSigners)); // apt-key has a --keyid parameter, but this requires gpg, so we call it without it // and instead check after the fact which keyids where used for verification @@ -191,7 +281,22 @@ string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile, { ioprintf(std::clog, "gpgv exited with status %i\n", WEXITSTATUS(status)); } - + + if (Debug) + { + std::cerr << "Summary:" << std::endl << " Good: "; + std::copy(GoodSigners.begin(), GoodSigners.end(), std::ostream_iterator(std::cerr, ", ")); + std::cerr << std::endl << " Bad: "; + std::copy(BadSigners.begin(), BadSigners.end(), std::ostream_iterator(std::cerr, ", ")); + std::cerr << std::endl << " Worthless: "; + std::copy(WorthlessSigners.begin(), WorthlessSigners.end(), std::ostream_iterator(std::cerr, ", ")); + std::cerr << std::endl << " SoonWorthless: "; + std::for_each(SoonWorthlessSigners.begin(), SoonWorthlessSigners.end(), [](Signer const &sig) { std::cerr << sig.key << ", "; }); + std::cerr << std::endl << " NoPubKey: "; + std::copy(NoPubKeySigners.begin(), NoPubKeySigners.end(), std::ostream_iterator(std::cerr, ", ")); + std::cerr << std::endl; + } + if (WEXITSTATUS(status) == 0) { if (keyIsID) @@ -233,6 +338,7 @@ bool GPGVMethod::URIAcquire(std::string const &Message, FetchItem *Itm) vector BadSigners; // a worthless signature is a expired or revoked one vector WorthlessSigners; + vector SoonWorthlessSigners; vector NoPubKeySigners; FetchResult Res; @@ -242,7 +348,20 @@ bool GPGVMethod::URIAcquire(std::string const &Message, FetchItem *Itm) // Run apt-key on file, extract contents and get the key ID of the signer string msg = VerifyGetSigners(Path.c_str(), Itm->DestFile.c_str(), key, GoodSigners, BadSigners, WorthlessSigners, - NoPubKeySigners); + SoonWorthlessSigners, NoPubKeySigners); + + // Check if all good signers are soon worthless and warn in that case + if (std::all_of(GoodSigners.begin(), GoodSigners.end(), [&](std::string const &good) { + return std::any_of(SoonWorthlessSigners.begin(), SoonWorthlessSigners.end(), [&](Signer const &weak) { + return IsTheSameKey(weak.key, good); + }); + })) + { + for (auto const & Signer : SoonWorthlessSigners) + // TRANSLATORS: The second %s is the reason and is untranslated for repository owners. + Warning(_("Signature by key %s uses weak digest algorithm (%s)"), Signer.key.c_str(), Signer.note.c_str()); + } + if (GoodSigners.empty() || !BadSigners.empty() || !NoPubKeySigners.empty()) { string errmsg;