Adding upstream version 1.8.2.3.upstream/1.8.2.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 522 insertions, 0 deletions

diff --git a/methods/gpgv.cc b/methods/gpgv.cc
new file mode 100644
index 0000000..f66e335
--- /dev/null
+++ b/methods/gpgv.cc
@@ -0,0 +1,522 @@
+#include <config.h>
+
+#include "aptmethod.h"
+#include <apt-pkg/configuration.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/gpgv.h>
+#include <apt-pkg/strutl.h>
+
+#include <ctype.h>
+#include <errno.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <algorithm>
+#include <array>
+#include <iostream>
+#include <iterator>
+#include <map>
+#include <sstream>
+#include <string>
+#include <vector>
+
+#include <apti18n.h>
+
+using std::string;
+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 GNUPGEXPKEYSIG "[GNUPG:] EXPKEYSIG"
+#define GNUPGEXPSIG "[GNUPG:] EXPSIG"
+#define GNUPGREVKEYSIG "[GNUPG:] REVKEYSIG"
+#define GNUPGNODATA "[GNUPG:] NODATA"
+#define APTKEYWARNING "[APTKEY:] WARNING"
+#define APTKEYERROR "[APTKEY:] ERROR"
+
+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, false) == true)
+	 return State::Untrusted;
+      if (_config->FindB(optionWeak, false) == true)
+	 return State::Weak;
+
+      return state;
+   }
+};
+
+static constexpr Digest Digests[] = {
+   {Digest::State::Untrusted, "Invalid digest"},
+   {Digest::State::Untrusted, "MD5"},
+   {Digest::State::Untrusted, "SHA1"},
+   {Digest::State::Untrusted, "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<unsigned>(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 fingerprint (40 = 24 + 16), GOODSIG can be longid (16) or
+   // fingerprint according to documentation in DETAILS.gz
+   if (goodsig.length() == 40 + strlen("GOODSIG "))
+      return validsig.compare(0, 40, goodsig, strlen("GOODSIG "), 40) == 0;
+   return validsig.compare(24, 16, goodsig, strlen("GOODSIG "), 16) == 0;
+}
+
+struct APT_HIDDEN SignersStorage {
+   std::vector<std::string> Good;
+   std::vector<std::string> Bad;
+   std::vector<std::string> Worthless;
+   // a worthless signature is a expired or revoked one
+   std::vector<Signer> SoonWorthless;
+   std::vector<std::string> NoPubKey;
+   std::vector<std::string> Valid;
+   std::vector<std::string> SignedBy;
+};
+class GPGVMethod : public aptMethod
+{
+   private:
+   string VerifyGetSigners(const char *file, const char *outfile,
+				vector<string> const &keyFpts,
+				vector<string> const &keyFiles,
+				SignersStorage &Signers);
+   protected:
+   virtual bool URIAcquire(std::string const &Message, FetchItem *Itm) APT_OVERRIDE;
+   public:
+   GPGVMethod() : aptMethod("gpgv", "1.1", SingleInstance | SendConfig){};
+};
+static void PushEntryWithKeyID(std::vector<std::string> &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 separator 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<std::string> &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);
+}
+static void implodeVector(std::vector<std::string> const &vec, std::ostream &out, char const * const sep)
+{
+   if (vec.empty())
+      return;
+   std::copy(vec.begin(), std::prev(vec.end()), std::ostream_iterator<std::string>(out, sep));
+   out << *vec.rbegin();
+   return;
+}
+string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile,
+					 vector<string> const &keyFpts,
+					 vector<string> const &keyFiles,
+					 SignersStorage &Signers)
+{
+   bool const Debug = DebugEnabled();
+
+   if (Debug == true)
+      std::clog << "inside VerifyGetSigners" << std::endl;
+
+   int fd[2];
+
+   if (pipe(fd) < 0)
+      return "Couldn't create pipe";
+
+   pid_t pid = fork();
+   if (pid < 0)
+      return string("Couldn't spawn new process") + strerror(errno);
+   else if (pid == 0)
+   {
+      std::ostringstream keys;
+      implodeVector(keyFiles, keys, ",");
+      ExecGPGV(outfile, file, 3, fd, keys.str());
+   }
+   close(fd[1]);
+
+   FILE *pipein = fdopen(fd[0], "r");
+
+   // Loop over the output of apt-key (which really is gnupg), and check the signatures.
+   std::vector<std::string> ErrSigners;
+   std::map<std::string, std::vector<std::string>> SubKeyMapping;
+   size_t buffersize = 0;
+   char *buffer = NULL;
+   bool gotNODATA = false;
+   while (1)
+   {
+      if (getline(&buffer, &buffersize, pipein) == -1)
+	 break;
+      if (Debug == true)
+         std::clog << "Read: " << buffer << std::endl;
+
+      // Push the data into three separate vectors, which
+      // we later concatenate.  They're kept separate so
+      // if we improve the apt method communication stuff later
+      // it will be better.
+      if (strncmp(buffer, GNUPGBADSIG, sizeof(GNUPGBADSIG)-1) == 0)
+	 PushEntryWithUID(Signers.Bad, buffer, Debug);
+      else if (strncmp(buffer, GNUPGERRSIG, sizeof(GNUPGERRSIG)-1) == 0)
+	 PushEntryWithKeyID(ErrSigners, buffer, Debug);
+      else if (strncmp(buffer, GNUPGNOPUBKEY, sizeof(GNUPGNOPUBKEY)-1) == 0)
+      {
+	 PushEntryWithKeyID(Signers.NoPubKey, 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());
+      }
+      else if (strncmp(buffer, GNUPGNODATA, sizeof(GNUPGNODATA)-1) == 0)
+	 gotNODATA = true;
+      else if (strncmp(buffer, GNUPGEXPKEYSIG, sizeof(GNUPGEXPKEYSIG)-1) == 0)
+	 PushEntryWithUID(Signers.Worthless, buffer, Debug);
+      else if (strncmp(buffer, GNUPGEXPSIG, sizeof(GNUPGEXPSIG)-1) == 0)
+	 PushEntryWithUID(Signers.Worthless, buffer, Debug);
+      else if (strncmp(buffer, GNUPGREVKEYSIG, sizeof(GNUPGREVKEYSIG)-1) == 0)
+	 PushEntryWithUID(Signers.Worthless, buffer, Debug);
+      else if (strncmp(buffer, GNUPGGOODSIG, sizeof(GNUPGGOODSIG)-1) == 0)
+	 PushEntryWithKeyID(Signers.Good, buffer, Debug);
+      else if (strncmp(buffer, GNUPGVALIDSIG, sizeof(GNUPGVALIDSIG)-1) == 0)
+      {
+         std::istringstream iss(buffer + sizeof(GNUPGVALIDSIG));
+         vector<string> tokens{std::istream_iterator<string>{iss},
+                               std::istream_iterator<string>{}};
+         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.
+            Signers.SoonWorthless.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.
+            Signers.Worthless.push_back(sig);
+            Signers.Good.erase(std::remove_if(Signers.Good.begin(), Signers.Good.end(), [&](std::string const &goodsig) {
+		     return IsTheSameKey(sig, goodsig); }), Signers.Good.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;
+         }
+
+	 Signers.Valid.push_back(sig);
+
+	 if (tokens.size() > 9 && sig != tokens[9])
+	    SubKeyMapping[tokens[9]].emplace_back(sig);
+      }
+      else if (strncmp(buffer, APTKEYWARNING, sizeof(APTKEYWARNING)-1) == 0)
+         Warning("%s", buffer + sizeof(APTKEYWARNING));
+      else if (strncmp(buffer, APTKEYERROR, sizeof(APTKEYERROR)-1) == 0)
+	 _error->Error("%s", buffer + sizeof(APTKEYERROR));
+   }
+   fclose(pipein);
+   free(buffer);
+   std::move(ErrSigners.begin(), ErrSigners.end(), std::back_inserter(Signers.Worthless));
+
+   // 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 (keyFpts.empty() == false)
+   {
+      if (Debug == true)
+      {
+	 std::clog << "GoodSigs needs to be limited to keyid(s): ";
+	 implodeVector(keyFpts, std::clog, ", ");
+	 std::clog << "\n";
+      }
+      std::vector<std::string> filteredGood;
+      for (auto &&good: Signers.Good)
+      {
+	 if (Debug == true)
+	    std::clog << "Key " << good << " is good sig, is it also a valid and allowed one? ";
+	 bool found = false;
+	 for (auto l : keyFpts)
+	 {
+	    bool exactKey = false;
+	    if (APT::String::Endswith(l, "!"))
+	    {
+	       exactKey = true;
+	       l.erase(l.length() - 1);
+	    }
+	    if (IsTheSameKey(l, good))
+	    {
+	       // GOODSIG might be "just" a longid, so we check VALIDSIG which is always a fingerprint
+	       if (std::find(Signers.Valid.cbegin(), Signers.Valid.cend(), l) == Signers.Valid.cend())
+		  continue;
+	       found = true;
+	       Signers.SignedBy.push_back(l + "!");
+	       break;
+	    }
+	    else if (exactKey == false)
+	    {
+	       auto const master = SubKeyMapping.find(l);
+	       if (master == SubKeyMapping.end())
+		  continue;
+	       for (auto const &sub : master->second)
+		  if (IsTheSameKey(sub, good))
+		  {
+		     if (std::find(Signers.Valid.cbegin(), Signers.Valid.cend(), sub) == Signers.Valid.cend())
+			continue;
+		     found = true;
+		     Signers.SignedBy.push_back(l);
+		     Signers.SignedBy.push_back(sub + "!");
+		     break;
+		  }
+	       if (found)
+		  break;
+	    }
+	 }
+	 if (Debug)
+	    std::clog << (found ? "yes" : "no") << "\n";
+	 if (found)
+	    filteredGood.emplace_back(std::move(good));
+	 else
+	    Signers.NoPubKey.emplace_back(std::move(good));
+      }
+      Signers.Good= std::move(filteredGood);
+   }
+   else
+   {
+      // for gpg an expired key is valid, too, but we want only the valid & good ones
+      for (auto const &v : Signers.Valid)
+		if (std::any_of(Signers.Good.begin(), Signers.Good.end(),
+					 [&v](std::string const &g) { return IsTheSameKey(v, g); }))
+		   Signers.SignedBy.push_back(v + "!");
+      for (auto sub : SubKeyMapping)
+	 if (std::any_of(sub.second.begin(), sub.second.end(),
+			 [&](std::string const &s) {
+			    if (std::find(Signers.Valid.begin(), Signers.Valid.end(), s) == Signers.Valid.end())
+			       return false;
+			    return std::any_of(Signers.Good.begin(), Signers.Good.end(),
+					       [&s](std::string const &g) { return IsTheSameKey(s, g); });
+			 }))
+	    Signers.SignedBy.push_back(sub.first);
+   }
+   std::sort(Signers.SignedBy.begin(), Signers.SignedBy.end());
+
+   int status;
+   waitpid(pid, &status, 0);
+   if (Debug == true)
+   {
+      ioprintf(std::clog, "gpgv exited with status %i\n", WEXITSTATUS(status));
+   }
+
+   if (Debug)
+   {
+      std::cerr << "Summary:\n  Good: ";
+      implodeVector(Signers.Good, std::cerr, ", ");
+      std::cerr << "\n  Valid: ";
+      implodeVector(Signers.Valid, std::cerr, ", ");
+      std::cerr << "\n  Bad: ";
+      implodeVector(Signers.Bad, std::cerr, ", ");
+      std::cerr << "\n  Worthless: ";
+      implodeVector(Signers.Worthless, std::cerr, ", ");
+      std::cerr << "\n  SoonWorthless: ";
+      std::for_each(Signers.SoonWorthless.begin(), Signers.SoonWorthless.end(), [](Signer const &sig) { std::cerr << sig.key << ", "; });
+      std::cerr << "\n  NoPubKey: ";
+      implodeVector(Signers.NoPubKey, std::cerr, ", ");
+      std::cerr << "\n  Signed-By: ";
+      implodeVector(Signers.SignedBy, std::cerr, ", ");
+      std::cerr << std::endl << "  NODATA: " << (gotNODATA ? "yes" : "no") << std::endl;
+   }
+
+   if (WEXITSTATUS(status) == 112)
+   {
+      // 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 (gotNODATA)
+   {
+      // 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 if (WEXITSTATUS(status) == 0)
+   {
+      if (keyFpts.empty() == false)
+      {
+	 // 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 (Signers.Good.empty())
+	    return _("At least one invalid signature was encountered.");
+      }
+      else
+      {
+	 if (Signers.Good.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::URIAcquire(std::string const &Message, FetchItem *Itm)
+{
+   URI const Get = Itm->Uri;
+   string const Path = Get.Host + Get.Path; // To account for relative paths
+   SignersStorage Signers;
+
+   std::vector<std::string> keyFpts, keyFiles;
+   for (auto &&key : VectorizeString(LookupTag(Message, "Signed-By"), ','))
+      if (key.empty() == false && key[0] == '/')
+	 keyFiles.emplace_back(std::move(key));
+      else
+	 keyFpts.emplace_back(std::move(key));
+
+   // Run apt-key on file, extract contents and get the key ID of the signer
+   string const msg = VerifyGetSigners(Path.c_str(), Itm->DestFile.c_str(), keyFpts, keyFiles, Signers);
+   if (_error->PendingError())
+      return false;
+
+   // Check if all good signers are soon worthless and warn in that case
+   if (std::all_of(Signers.Good.begin(), Signers.Good.end(), [&](std::string const &good) {
+	    return std::any_of(Signers.SoonWorthless.begin(), Signers.SoonWorthless.end(), [&](Signer const &weak) {
+		  return IsTheSameKey(weak.key, good);
+		  });
+	    }))
+   {
+      for (auto const & Signer : Signers.SoonWorthless)
+         // 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 (Signers.Good.empty() || !Signers.Bad.empty() || !Signers.NoPubKey.empty())
+   {
+      string errmsg;
+      // In this case, something bad probably happened, so we just go
+      // with what the other method gave us for an error message.
+      if (Signers.Bad.empty() && Signers.Worthless.empty() && Signers.NoPubKey.empty())
+         errmsg = msg;
+      else
+      {
+         if (!Signers.Bad.empty())
+         {
+            errmsg += _("The following signatures were invalid:\n");
+            for (auto const &I : Signers.Bad)
+               errmsg.append(I).append("\n");
+         }
+         if (!Signers.Worthless.empty())
+         {
+            errmsg += _("The following signatures were invalid:\n");
+            for (auto const &I : Signers.Worthless)
+               errmsg.append(I).append("\n");
+         }
+         if (!Signers.NoPubKey.empty())
+         {
+             errmsg += _("The following signatures couldn't be verified because the public key is not available:\n");
+            for (auto const &I : Signers.NoPubKey)
+               errmsg.append(I).append("\n");
+         }
+      }
+      // this is only fatal if we have no good sigs or if we have at
+      // least one bad signature. good signatures and NoPubKey signatures
+      // happen easily when a file is signed with multiple signatures
+      if (Signers.Good.empty() or !Signers.Bad.empty())
+	 return _error->Error("%s", errmsg.c_str());
+   }
+
+   std::unordered_map<std::string, std::string> fields;
+   fields.emplace("URI", Itm->Uri);
+   fields.emplace("Filename", Itm->DestFile);
+   if (Signers.SignedBy.empty() == false)
+   {
+      std::ostringstream out;
+      implodeVector(Signers.SignedBy, out, "\n");
+      fields.emplace("Signed-By", out.str());
+   }
+   {
+      // Just pass the raw output up, because passing it as a real data
+      // structure is too difficult with the method stuff.  We keep it
+      // as three separate vectors for future extensibility.
+      std::vector<std::string> gpgvoutput;
+      std::move(Signers.Good.begin(), Signers.Good.end(), std::back_inserter(gpgvoutput));
+      std::move(Signers.Bad.begin(), Signers.Bad.end(), std::back_inserter(gpgvoutput));
+      std::move(Signers.NoPubKey.begin(), Signers.NoPubKey.end(), std::back_inserter(gpgvoutput));
+      if (gpgvoutput.empty() == false)
+      {
+	 std::ostringstream out;
+	 implodeVector(gpgvoutput, out, "\n");
+	 fields.emplace("GPGVOutput", out.str());
+      }
+   }
+   SendMessage("201 URI Done", std::move(fields));
+   Dequeue();
+
+   if (DebugEnabled())
+      std::clog << "apt-key succeeded\n";
+
+   return true;
+}
+
+
+int main()
+{
+   return GPGVMethod().Run();
+}