X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/71ecaad29d8066a494f516efc5efd80860653fe2..2fac0dd5a7a62b67a869cd4c71c9d09159aaa31d:/methods/gpgv.cc diff --git a/methods/gpgv.cc b/methods/gpgv.cc index 2b2aba017..dd395d659 100644 --- a/methods/gpgv.cc +++ b/methods/gpgv.cc @@ -1,19 +1,28 @@ #include -#include #include +#include +#include +#include #include #include -#include -#include +#include "aptmethod.h" -#include -#include -#include +#include #include +#include +#include +#include +#include #include -#include +#include + +#include +#include #include +#include +#include +#include #include #include @@ -23,45 +32,129 @@ using std::vector; #define GNUPGPREFIX "[GNUPG:]" #define GNUPGBADSIG "[GNUPG:] BADSIG" +#define GNUPGERRSIG "[GNUPG:] ERRSIG" #define GNUPGNOPUBKEY "[GNUPG:] NO_PUBKEY" #define GNUPGVALIDSIG "[GNUPG:] VALIDSIG" #define GNUPGGOODSIG "[GNUPG:] GOODSIG" -#define GNUPGKEYEXPIRED "[GNUPG:] KEYEXPIRED" +#define GNUPGEXPKEYSIG "[GNUPG:] EXPKEYSIG" +#define GNUPGEXPSIG "[GNUPG:] EXPSIG" #define GNUPGREVKEYSIG "[GNUPG:] REVKEYSIG" #define GNUPGNODATA "[GNUPG:] NODATA" -class GPGVMethod : public pkgAcqMethod +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: string VerifyGetSigners(const char *file, const char *outfile, - vector &GoodSigners, + std::string const &key, + vector &GoodSigners, vector &BadSigners, vector &WorthlessSigners, + vector &SoonWorthlessSigners, vector &NoPubKeySigners); - protected: - virtual bool Fetch(FetchItem *Itm); - + virtual bool URIAcquire(std::string const &Message, FetchItem *Itm) APT_OVERRIDE; public: - - GPGVMethod() : pkgAcqMethod("1.0",SingleInstance | SendConfig) {}; + GPGVMethod() : aptMethod("gpgv","1.0",SingleInstance | SendConfig) {}; }; - +static void PushEntryWithKeyID(std::vector &Signers, char * const buffer, bool const Debug) +{ + char * const msg = buffer + sizeof(GNUPGPREFIX); + char *p = msg; + // skip the message + while (*p && !isspace(*p)) + ++p; + // skip the seperator whitespace + ++p; + // skip the hexdigit fingerprint + while (*p && isxdigit(*p)) + ++p; + // cut the rest from the message + *p = '\0'; + if (Debug == true) + std::clog << "Got " << msg << " !" << std::endl; + Signers.push_back(msg); +} +static void PushEntryWithUID(std::vector &Signers, char * const buffer, bool const Debug) +{ + std::string msg = buffer + sizeof(GNUPGPREFIX); + auto const nuke = msg.find_last_not_of("\n\t\r"); + if (nuke != std::string::npos) + msg.erase(nuke + 1); + if (Debug == true) + std::clog << "Got " << msg << " !" << std::endl; + Signers.push_back(msg); +} string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile, + std::string const &key, vector &GoodSigners, vector &BadSigners, vector &WorthlessSigners, + vector &SoonWorthlessSigners, vector &NoPubKeySigners) { bool const Debug = _config->FindB("Debug::Acquire::gpgv", false); - // setup a (empty) stringstream for formating the return value - std::stringstream ret; - ret.str(""); if (Debug == true) std::clog << "inside VerifyGetSigners" << std::endl; int fd[2]; + bool const keyIsID = (key.empty() == false && key[0] != '/'); if (pipe(fd) < 0) return "Couldn't create pipe"; @@ -70,43 +163,21 @@ string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile, if (pid < 0) return string("Couldn't spawn new process") + strerror(errno); else if (pid == 0) - { - _error->PushToStack(); - bool const success = SigVerify::RunGPGV(outfile, file, 3, fd); - if (success == false) - { - string errmsg; - _error->PopMessage(errmsg); - _error->RevertToStack(); - return errmsg; - } - _error->RevertToStack(); - exit(111); - } + ExecGPGV(outfile, file, 3, fd, (keyIsID ? "" : key)); close(fd[1]); FILE *pipein = fdopen(fd[0], "r"); - // Loop over the output of gpgv, and check the signatures. - size_t buffersize = 64; - char *buffer = (char *) malloc(buffersize); - size_t bufferoff = 0; + // 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; + bool gotNODATA = false; while (1) { - int c; - - // Read a line. Sigh. - while ((c = getc(pipein)) != EOF && c != '\n') - { - if (bufferoff == buffersize) - buffer = (char *) realloc(buffer, buffersize *= 2); - *(buffer+bufferoff) = c; - bufferoff++; - } - if (bufferoff == 0 && c == EOF) - break; - *(buffer+bufferoff) = '\0'; - bufferoff = 0; + if (getline(&buffer, &buffersize, pipein) == -1) + break; if (Debug == true) std::clog << "Read: " << buffer << std::endl; @@ -115,97 +186,190 @@ string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile, // if we improve the apt method communication stuff later // it will be better. if (strncmp(buffer, GNUPGBADSIG, sizeof(GNUPGBADSIG)-1) == 0) + PushEntryWithUID(BadSigners, buffer, Debug); + else if (strncmp(buffer, GNUPGERRSIG, sizeof(GNUPGERRSIG)-1) == 0) + PushEntryWithKeyID(ErrSigners, buffer, Debug); + else if (strncmp(buffer, GNUPGNOPUBKEY, sizeof(GNUPGNOPUBKEY)-1) == 0) { - if (Debug == true) - std::clog << "Got BADSIG! " << std::endl; - BadSigners.push_back(string(buffer+sizeof(GNUPGPREFIX))); - } - - 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))); - } - if (strncmp(buffer, GNUPGNODATA, sizeof(GNUPGBADSIG)-1) == 0) - { - if (Debug == true) - std::clog << "Got NODATA! " << std::endl; - BadSigners.push_back(string(buffer+sizeof(GNUPGPREFIX))); + PushEntryWithKeyID(NoPubKeySigners, buffer, Debug); + ErrSigners.erase(std::remove_if(ErrSigners.begin(), ErrSigners.end(), [&](std::string const &errsig) { + return errsig.compare(strlen("ERRSIG "), 16, buffer, sizeof(GNUPGNOPUBKEY), 16) == 0; }), ErrSigners.end()); } - if (strncmp(buffer, GNUPGKEYEXPIRED, sizeof(GNUPGKEYEXPIRED)-1) == 0) + else if (strncmp(buffer, GNUPGNODATA, sizeof(GNUPGNODATA)-1) == 0) + gotNODATA = true; + else if (strncmp(buffer, GNUPGEXPKEYSIG, sizeof(GNUPGEXPKEYSIG)-1) == 0) + PushEntryWithUID(WorthlessSigners, buffer, Debug); + else if (strncmp(buffer, GNUPGEXPSIG, sizeof(GNUPGEXPSIG)-1) == 0) + PushEntryWithUID(WorthlessSigners, buffer, Debug); + else if (strncmp(buffer, GNUPGREVKEYSIG, sizeof(GNUPGREVKEYSIG)-1) == 0) + PushEntryWithUID(WorthlessSigners, buffer, Debug); + else if (strncmp(buffer, GNUPGGOODSIG, sizeof(GNUPGGOODSIG)-1) == 0) + PushEntryWithKeyID(GoodSigners, buffer, Debug); + else if (strncmp(buffer, GNUPGVALIDSIG, sizeof(GNUPGVALIDSIG)-1) == 0) { - if (Debug == true) - std::clog << "Got KEYEXPIRED! " << std::endl; - WorthlessSigners.push_back(string(buffer+sizeof(GNUPGPREFIX))); + std::istringstream iss(buffer + sizeof(GNUPGVALIDSIG)); + vector tokens{std::istream_iterator{iss}, + std::istream_iterator{}}; + auto const sig = tokens[0]; + // 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({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(sig); + GoodSigners.erase(std::remove_if(GoodSigners.begin(), GoodSigners.end(), [&](std::string const &goodsig) { + return IsTheSameKey(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(sig); } - if (strncmp(buffer, GNUPGREVKEYSIG, sizeof(GNUPGREVKEYSIG)-1) == 0) + } + 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 + if (keyIsID == true) + { + if (Debug == true) + std::clog << "GoodSigs needs to be limited to keyid " << key << std::endl; + bool foundGood = false; + for (auto const &k: VectorizeString(key, ',')) { - if (Debug == true) - std::clog << "Got REVKEYSIG! " << std::endl; - WorthlessSigners.push_back(string(buffer+sizeof(GNUPGPREFIX))); + if (std::find(ValidSigners.begin(), ValidSigners.end(), k) == ValidSigners.end()) + continue; + // we look for GOODSIG here as well as an expired sig is a valid sig as well (but not a good one) + std::string const goodlongkeyid = "GOODSIG " + k.substr(24, 16); + foundGood = std::find(GoodSigners.begin(), GoodSigners.end(), goodlongkeyid) != GoodSigners.end(); + if (Debug == true) + std::clog << "Key " << k << " is valid sig, is " << goodlongkeyid << " also a good one? " << (foundGood ? "yes" : "no") << std::endl; + if (foundGood == false) + continue; + std::copy(GoodSigners.begin(), GoodSigners.end(), std::back_insert_iterator >(NoPubKeySigners)); + GoodSigners.clear(); + GoodSigners.push_back(goodlongkeyid); + NoPubKeySigners.erase(std::remove(NoPubKeySigners.begin(), NoPubKeySigners.end(), goodlongkeyid), NoPubKeySigners.end()); + break; } - if (strncmp(buffer, GNUPGGOODSIG, sizeof(GNUPGGOODSIG)-1) == 0) + if (foundGood == false) { - char *sig = buffer + sizeof(GNUPGPREFIX); - char *p = sig + sizeof("GOODSIG"); - while (*p && isxdigit(*p)) - p++; - *p = 0; - if (Debug == true) - std::clog << "Got GOODSIG, key ID:" << sig << std::endl; - GoodSigners.push_back(string(sig)); + std::copy(GoodSigners.begin(), GoodSigners.end(), std::back_insert_iterator >(NoPubKeySigners)); + GoodSigners.clear(); } } - fclose(pipein); int status; waitpid(pid, &status, 0); if (Debug == true) { - std::clog << "gpgv exited\n"; + ioprintf(std::clog, "gpgv exited with status %i\n", WEXITSTATUS(status)); } - - if (WEXITSTATUS(status) == 0) + + if (Debug) { - if (GoodSigners.empty()) - return _("Internal error: Good signature, but could not determine key fingerprint?!"); - return ""; + 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 << " NODATA: " << (gotNODATA ? "yes" : "no") << std::endl; } - else if (WEXITSTATUS(status) == 1) + + if (WEXITSTATUS(status) == 112) { - return _("At least one invalid signature was encountered."); + // acquire system checks for "NODATA" to generate GPG errors (the others are only warnings) + std::string errmsg; + //TRANSLATORS: %s is a single techy word like 'NODATA' + strprintf(errmsg, _("Clearsigned file isn't valid, got '%s' (does the network require authentication?)"), "NODATA"); + return errmsg; } - else if (WEXITSTATUS(status) == 111) + else if (gotNODATA) { - ioprintf(ret, _("Could not execute 'gpgv' to verify signature (is gpgv installed?)")); - return ret.str(); + // acquire system checks for "NODATA" to generate GPG errors (the others are only warnings) + std::string errmsg; + //TRANSLATORS: %s is a single techy word like 'NODATA' + strprintf(errmsg, _("Signed file isn't valid, got '%s' (does the network require authentication?)"), "NODATA"); + return errmsg; } - else + else if (WEXITSTATUS(status) == 0) { - return _("Unknown error executing gpgv"); + if (keyIsID) + { + // gpgv will report success, but we want to enforce a certain keyring + // so if we haven't found the key the valid we found is in fact invalid + if (GoodSigners.empty()) + return _("At least one invalid signature was encountered."); + } + else + { + if (GoodSigners.empty()) + return _("Internal error: Good signature, but could not determine key fingerprint?!"); + } + return ""; } + else if (WEXITSTATUS(status) == 1) + return _("At least one invalid signature was encountered."); + else if (WEXITSTATUS(status) == 111) + return _("Could not execute 'apt-key' to verify signature (is gnupg installed?)"); + else + return _("Unknown error executing apt-key"); } -bool GPGVMethod::Fetch(FetchItem *Itm) +bool GPGVMethod::URIAcquire(std::string const &Message, FetchItem *Itm) { - URI Get = Itm->Uri; - string Path = Get.Host + Get.Path; // To account for relative paths - string keyID; + URI const Get = Itm->Uri; + string const Path = Get.Host + Get.Path; // To account for relative paths + std::string const key = LookupTag(Message, "Signed-By"); vector GoodSigners; vector BadSigners; // a worthless signature is a expired or revoked one vector WorthlessSigners; + vector SoonWorthlessSigners; vector NoPubKeySigners; FetchResult Res; Res.Filename = Itm->DestFile; URIStart(Res); - // Run gpgv on file, extract contents and get the key ID of the signer - string msg = VerifyGetSigners(Path.c_str(), Itm->DestFile.c_str(), + // 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; @@ -248,13 +412,13 @@ bool GPGVMethod::Fetch(FetchItem *Itm) // structure is too difficult with the method stuff. We keep it // as three separate vectors for future extensibility. Res.GPGVOutput = GoodSigners; - Res.GPGVOutput.insert(Res.GPGVOutput.end(),BadSigners.begin(),BadSigners.end()); - Res.GPGVOutput.insert(Res.GPGVOutput.end(),NoPubKeySigners.begin(),NoPubKeySigners.end()); + std::move(BadSigners.begin(), BadSigners.end(), std::back_inserter(Res.GPGVOutput)); + std::move(NoPubKeySigners.begin(), NoPubKeySigners.end(), std::back_inserter(Res.GPGVOutput)); URIDone(Res); if (_config->FindB("Debug::Acquire::gpgv", false)) { - std::clog << "gpgv succeeded\n"; + std::clog << "apt-key succeeded\n"; } return true; @@ -264,7 +428,7 @@ bool GPGVMethod::Fetch(FetchItem *Itm) int main() { setlocale(LC_ALL, ""); - + GPGVMethod Mth; return Mth.Run();