#include <apt-pkg/gpgv.h>
#include <apt-pkg/strutl.h>
#include <apt-pkg/fileutl.h>
+#include "aptmethod.h"
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <sys/wait.h>
#include <unistd.h>
+
+#include <array>
+#include <algorithm>
+#include <sstream>
+#include <iterator>
#include <iostream>
#include <string>
#include <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<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 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<string> &GoodSigners,
+ std::string const &key,
+ vector<string> &GoodSigners,
vector<string> &BadSigners,
vector<string> &WorthlessSigners,
+ vector<Signer> &SoonWorthlessSigners,
vector<string> &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<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 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<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);
+}
string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile,
+ std::string const &key,
vector<string> &GoodSigners,
vector<string> &BadSigners,
vector<string> &WorthlessSigners,
+ vector<Signer> &SoonWorthlessSigners,
vector<string> &NoPubKeySigners)
{
bool const Debug = _config->FindB("Debug::Acquire::gpgv", false);
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";
if (pid < 0)
return string("Couldn't spawn new process") + strerror(errno);
else if (pid == 0)
- ExecGPGV(outfile, file, 3, fd);
+ 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<std::string> ValidSigners;
+ std::vector<std::string> ErrSigners;
+ size_t buffersize = 0;
+ char *buffer = NULL;
while (1)
{
- int c;
-
- // Read a line. Sigh.
- while ((c = getc(pipein)) != EOF && c != '\n')
- {
- if (bufferoff == buffersize)
- {
- char* newBuffer = (char *) realloc(buffer, buffersize *= 2);
- if (newBuffer == NULL)
- {
- free(buffer);
- return "Couldn't allocate a buffer big enough for reading";
- }
- buffer = newBuffer;
- }
- *(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;
// 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)));
+ 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, GNUPGNODATA, sizeof(GNUPGBADSIG)-1) == 0)
+ else if (strncmp(buffer, GNUPGNODATA, sizeof(GNUPGBADSIG)-1) == 0)
+ PushEntryWithUID(BadSigners, buffer, Debug);
+ 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 NODATA! " << std::endl;
- BadSigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
- }
- if (strncmp(buffer, GNUPGKEYEXPIRED, sizeof(GNUPGKEYEXPIRED)-1) == 0)
- {
- if (Debug == true)
- std::clog << "Got KEYEXPIRED! " << std::endl;
- WorthlessSigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
- }
- if (strncmp(buffer, GNUPGREVKEYSIG, sizeof(GNUPGREVKEYSIG)-1) == 0)
- {
- if (Debug == true)
- std::clog << "Got REVKEYSIG! " << std::endl;
- WorthlessSigners.push_back(string(buffer+sizeof(GNUPGPREFIX)));
- }
- if (strncmp(buffer, GNUPGGOODSIG, sizeof(GNUPGGOODSIG)-1) == 0)
- {
- 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::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.
+ 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);
}
}
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;
+ std::vector<std::string>::iterator const foundItr = std::find(ValidSigners.begin(), ValidSigners.end(), key);
+ bool const found = (foundItr != ValidSigners.end());
+ std::copy(GoodSigners.begin(), GoodSigners.end(), std::back_insert_iterator<std::vector<std::string> >(NoPubKeySigners));
+ if (found)
+ {
+ // 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 " + key.substr(24, 16);
+ bool const foundGood = std::find(GoodSigners.begin(), GoodSigners.end(), goodlongkeyid) != GoodSigners.end();
+ if (Debug == true)
+ std::clog << "Key " << key << " is valid sig, is " << goodlongkeyid << " also a good one? " << (foundGood ? "yes" : "no") << std::endl;
+ GoodSigners.clear();
+ if (foundGood)
+ {
+ GoodSigners.push_back(goodlongkeyid);
+ NoPubKeySigners.erase(std::remove(NoPubKeySigners.begin(), NoPubKeySigners.end(), goodlongkeyid), NoPubKeySigners.end());
+ }
+ }
+ else
+ GoodSigners.clear();
+ }
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 (Debug)
+ {
+ std::cerr << "Summary:" << std::endl << " Good: ";
+ std::copy(GoodSigners.begin(), GoodSigners.end(), std::ostream_iterator<std::string>(std::cerr, ", "));
+ std::cerr << std::endl << " Bad: ";
+ std::copy(BadSigners.begin(), BadSigners.end(), std::ostream_iterator<std::string>(std::cerr, ", "));
+ std::cerr << std::endl << " Worthless: ";
+ std::copy(WorthlessSigners.begin(), WorthlessSigners.end(), std::ostream_iterator<std::string>(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::string>(std::cerr, ", "));
+ std::cerr << std::endl;
+ }
+
if (WEXITSTATUS(status) == 0)
{
- if (GoodSigners.empty())
- return _("Internal error: Good signature, but could not determine key fingerprint?!");
+ 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 'gpgv' to verify signature (is gpgv installed?)");
+ return _("Could not execute 'apt-key' to verify signature (is gnupg installed?)");
else if (WEXITSTATUS(status) == 112)
{
// acquire system checks for "NODATA" to generate GPG errors (the others are only warnings)
return errmsg;
}
else
- return _("Unknown error executing gpgv");
+ 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<string> GoodSigners;
vector<string> BadSigners;
// a worthless signature is a expired or revoked one
vector<string> WorthlessSigners;
+ vector<Signer> SoonWorthlessSigners;
vector<string> 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;
// 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;
int main()
{
setlocale(LC_ALL, "");
-
- DropPrivs();
GPGVMethod Mth;