diff options
Diffstat (limited to 'apt-pkg/contrib/gpgv.cc')
| -rw-r--r-- | apt-pkg/contrib/gpgv.cc | 254 |
1 files changed, 190 insertions, 64 deletions
diff --git a/apt-pkg/contrib/gpgv.cc b/apt-pkg/contrib/gpgv.cc index 147f15d9d..43c634dde 100644 --- a/apt-pkg/contrib/gpgv.cc +++ b/apt-pkg/contrib/gpgv.cc @@ -18,11 +18,13 @@ #include <unistd.h> #include <algorithm> +#include <forward_list> #include <fstream> #include <iostream> #include <memory> #include <sstream> #include <string> +#include <unordered_map> #include <vector> #include <apti18n.h> @@ -112,7 +114,9 @@ static bool operator!=(LineBuffer const &buf, std::string_view const exp) noexce And as a cherry on the cake, we use our apt-key wrapper to do part of the lifting in regards to merging keyrings. Fun for the whole family. */ -static void APT_PRINTF(4) apt_error(std::ostream &outterm, int const statusfd, int fd[2], const char *format, ...) +#define apt_error(...) apt_msg("ERROR", __VA_ARGS__) +#define apt_warning(...) apt_msg("WARNING", __VA_ARGS__) +static void APT_PRINTF(5) apt_msg(std::string const &tag, std::ostream &outterm, int const statusfd, int fd[2], const char *format, ...) { std::ostringstream outstr; std::ostream &out = (statusfd == -1) ? outterm : outstr; @@ -128,53 +132,197 @@ static void APT_PRINTF(4) apt_error(std::ostream &outterm, int const statusfd, i } if (statusfd != -1) { - auto const errtag = "[APTKEY:] ERROR "; + auto const errtag = "[APTKEY:] " + tag + " "; outstr << '\n'; auto const errtext = outstr.str(); - if (not FileFd::Write(fd[1], errtag, strlen(errtag)) || + if (not FileFd::Write(fd[1], errtag.data(), errtag.size()) || not FileFd::Write(fd[1], errtext.data(), errtext.size())) outterm << errtext << std::flush; } } + +static bool CheckGPGV(std::unordered_map<std::string, std::forward_list<std::string>> &checkedCommands, std::string gpgv, bool Debug) +{ + if (checkedCommands.find(gpgv) == checkedCommands.end()) + { + // Create entry + checkedCommands[gpgv]; + FileFd dumpOptions; + pid_t child; + const char *argv[] = {gpgv.c_str(), "--dump-options", nullptr}; + if (unlikely(Debug)) + std::clog << "Executing " << gpgv << " --dump-options" << std::endl; + if (not Popen(argv, dumpOptions, child, FileFd::ReadOnly) && Debug) + return false; + + for (std::string line; dumpOptions.ReadLine(line);) + { + if (unlikely(Debug)) + std::clog << "Read line: " << line << std::endl; + checkedCommands[gpgv].push_front(APT::String::Strip(line)); + } + dumpOptions.Close(); + waitpid(child, NULL, 0); + } + return not checkedCommands[gpgv].empty(); +} + +std::pair<std::string, std::forward_list<std::string>> APT::Internal::FindGPGV(bool Debug) +{ + static thread_local std::unordered_map<std::string, std::forward_list<std::string>> checkedCommands; + const std::string gpgvVariants[] = { + _config->Find("Apt::Key::gpgvcommand"), + // Prefer absolute path + "/usr/bin/gpgv-sq", + "/usr/bin/gpgv", + "/usr/bin/gpgv2", + "/usr/bin/gpgv1", + "gpgv-sq", + "gpgv", + "gpgv2", + "gpgv1", + }; + for (auto gpgv : gpgvVariants) + if (CheckGPGV(checkedCommands, gpgv, Debug)) + return std::make_pair(gpgv, checkedCommands[gpgv]); + return {}; +} + void ExecGPGV(std::string const &File, std::string const &FileGPG, int const &statusfd, int fd[2], std::string const &key) { - #define EINTERNAL 111 - std::string const aptkey = _config->Find("Dir::Bin::apt-key", CMAKE_INSTALL_FULL_BINDIR "/apt-key"); + auto const keyFiles = VectorizeString(key, ','); + ExecGPGV(File, FileGPG, statusfd, fd, keyFiles); +} +void ExecGPGV(std::string const &File, std::string const &FileGPG, + int const &statusfd, int fd[2], std::vector<std::string> const &KeyFiles) +{ +#define EINTERNAL 111 bool const Debug = _config->FindB("Debug::Acquire::gpgv", false); struct exiter { - std::vector<const char *> files; + std::vector<std::string> files; void operator ()(int code) APT_NORETURN { - std::for_each(files.begin(), files.end(), unlink); + std::for_each(files.begin(), files.end(), [](auto f) + { unlink(f.c_str()); }); exit(code); } } local_exit; + auto [gpgv, supportedOptions] = APT::Internal::FindGPGV(Debug); + if (gpgv.empty()) + { + apt_error(std::cerr, statusfd, fd, "Couldn't find a gpgv binary"); + local_exit(EINTERNAL); + } - std::vector<const char *> Args; + std::vector<std::string> Args; Args.reserve(10); - Args.push_back(aptkey.c_str()); - Args.push_back("--quiet"); - Args.push_back("--readonly"); - auto const keysFileFpr = VectorizeString(key, ','); - for (auto const &k: keysFileFpr) + Args.push_back(gpgv); + Args.push_back("--ignore-time-conflict"); + + auto dearmorKeyOrCheckFormat = [&](std::string const &k) -> std::string + { + FileFd keyFd(k, FileFd::ReadOnly); + if (not keyFd.IsOpen()) + { + apt_warning(std::cerr, statusfd, fd, "The key(s) in the keyring %s are ignored as the file is not readable by user executing apt-key.\n", k.c_str()); + return ""; + } + if (APT::String::Endswith(k, ".gpg") || APT::String::Endswith(k, ".pub")) + { + unsigned char c; + if (not keyFd.Read(&c, sizeof(c))) + goto err; + // Identify the leading byte of an OpenPGP public key packet + // 0x98 -- old-format OpenPGP public key packet, up to 255 octets + // 0x99 -- old-format OpenPGP public key packet, 256-65535 octets + // 0xc6 -- new-format OpenPGP public key packet, any length + if (c == 0x98 || c == 0x99 || c == 0xc6) + return k; + } + else if (APT::String::Endswith(k, ".asc")) + { + std::string b64msg; + int state = 0; + for (std::string line; keyFd.ReadLine(line);) + { + line = APT::String::Strip(line); + if (APT::String::Startswith(line, "-----BEGIN PGP PUBLIC KEY BLOCK-----")) + state = 1; + else if (state == 1 && line == "") + state = 2; + else if (state == 2 && line != "" && line[0] != '=' && line[0] != '-') + b64msg += line; + else if (APT::String::Startswith(line, "-----END")) + state = 3; + } + if (state != 3) + goto err; + + FileFd dearmoredFd; + if (GetTempFile("apt.XXXXXX.gpg", false, &dearmoredFd) == nullptr) + local_exit(EINTERNAL); + if (auto decoded = Base64Decode(b64msg); not decoded.empty()) + dearmoredFd.Write(decoded.data(), decoded.size()); + local_exit.files.push_back(dearmoredFd.Name()); + return dearmoredFd.Name(); + } + err: + apt_warning(std::cerr, statusfd, fd, "The key(s) in the keyring %s are ignored as the file has an unsupported filetype.", k.c_str()); + return ""; + }; + auto maybeAddKeyring = [&](std::string const &k) + { + if (struct stat st; stat(k.c_str(), &st) != 0 || st.st_size == 0) + return; + if (auto cleanKey = dearmorKeyOrCheckFormat(k); not cleanKey.empty()) + { + Args.push_back("--keyring"); + Args.push_back(cleanKey); + } + return; + }; + + for (auto const &k : KeyFiles) { if (unlikely(k.empty())) continue; if (k[0] == '/') { - Args.push_back("--keyring"); - Args.push_back(k.c_str()); + if (Debug) + std::clog << "Trying Signed-By: " << k << std::endl; + + maybeAddKeyring(k); } else { Args.push_back("--keyid"); - Args.push_back(k.c_str()); + Args.push_back(k); } } - Args.push_back("verify"); + + std::vector<std::string> Parts; + if (std::find(Args.begin(), Args.end(), "--keyring") == Args.end()) + { + Parts = GetListOfFilesInDir(_config->FindDir("Dir::Etc::TrustedParts"), std::vector<std::string>{"gpg", "asc"}, true); + if (char *env = getenv("APT_KEY_NO_LEGACY_KEYRING"); env == nullptr || not StringToBool(env, false)) + Parts.insert(Parts.begin(), _config->FindFile("Dir::Etc::Trusted")); + for (auto &Part : Parts) + { + if (Debug) + std::clog << "Trying TrustedPart: " << Part << std::endl; + maybeAddKeyring(Part); + } + } + + // If we do not give it any keyring, gpgv shouts keydb errors at us + if (std::find(Args.begin(), Args.end(), "--keyring") == Args.end()) + { + Args.push_back("--keyring"); + Args.push_back("/dev/null"); + } char statusfdstr[10]; if (statusfd != -1) @@ -184,6 +332,12 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, Args.push_back(statusfdstr); } + if (auto assertPubkeyAlgo = _config->Find("Apt::Key::assert-pubkey-algo"); not assertPubkeyAlgo.empty()) + { + if (std::find(supportedOptions.begin(), supportedOptions.end(), "--assert-pubkey-algo") != supportedOptions.end()) + Args.push_back("--assert-pubkey-algo=" + assertPubkeyAlgo); + } + Configuration::Item const *Opts; Opts = _config->Tree("Acquire::gpgv::Options"); if (Opts != 0) @@ -193,42 +347,11 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, { if (Opts->Value.empty()) continue; - Args.push_back(Opts->Value.c_str()); + Args.push_back(Opts->Value); } } enum { DETACHED, CLEARSIGNED } releaseSignature = (FileGPG != File) ? DETACHED : CLEARSIGNED; - std::unique_ptr<char, FreeDeleter> sig; - std::unique_ptr<char, FreeDeleter> data; - std::unique_ptr<char, FreeDeleter> conf; - - // Dump the configuration so apt-key picks up the correct Dir values - { - { - std::string tmpfile; - strprintf(tmpfile, "%s/apt.conf.XXXXXX", GetTempDir().c_str()); - conf.reset(strdup(tmpfile.c_str())); - } - if (conf == nullptr) { - apt_error(std::cerr, statusfd, fd, "Couldn't create tempfile names for passing config to apt-key"); - local_exit(EINTERNAL); - } - int confFd = mkstemp(conf.get()); - if (confFd == -1) { - apt_error(std::cerr, statusfd, fd, "Couldn't create temporary file %s for passing config to apt-key", conf.get()); - local_exit(EINTERNAL); - } - local_exit.files.push_back(conf.get()); - - std::ofstream confStream(conf.get()); - close(confFd); - _config->Dump(confStream); - confStream.close(); - setenv("APT_CONFIG", conf.get(), 1); - } - - // Tell apt-key not to emit warnings - setenv("APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE", "1", 1); if (releaseSignature == DETACHED) { @@ -307,21 +430,19 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, local_exit(112); } - Args.push_back(FileGPG.c_str()); - Args.push_back(File.c_str()); + Args.push_back(FileGPG); + Args.push_back(File); } else // clear-signed file { FileFd signature; if (GetTempFile("apt.sig", false, &signature) == nullptr) local_exit(EINTERNAL); - sig.reset(strdup(signature.Name().c_str())); - local_exit.files.push_back(sig.get()); + local_exit.files.push_back(signature.Name()); FileFd message; if (GetTempFile("apt.data", false, &message) == nullptr) local_exit(EINTERNAL); - data.reset(strdup(message.Name().c_str())); - local_exit.files.push_back(data.get()); + local_exit.files.push_back(message.Name()); if (signature.Failed() || message.Failed() || not SplitClearSignedFile(File, &message, nullptr, &signature)) @@ -329,17 +450,15 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, apt_error(std::cerr, statusfd, fd, "Splitting up %s into data and signature failed", File.c_str()); local_exit(112); } - Args.push_back(sig.get()); - Args.push_back(data.get()); + Args.push_back(signature.Name()); + Args.push_back(message.Name()); } - Args.push_back(NULL); - if (Debug) { std::clog << "Preparing to exec: "; - for (std::vector<const char *>::const_iterator a = Args.begin(); *a != NULL; ++a) - std::clog << " " << *a; + for (auto const &a : Args) + std::clog << " " << a; std::clog << std::endl; } @@ -360,20 +479,27 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, putenv((char *)"LC_MESSAGES="); } + // Translate the argument list to a C array. This should happen before + // the fork so we don't allocate money between fork() and execvp(). + std::vector<const char *> cArgs; + cArgs.reserve(Args.size() + 1); + for (auto const &arg : Args) + cArgs.push_back(arg.c_str()); + cArgs.push_back(nullptr); // We have created tempfiles we have to clean up // and we do an additional check, so fork yet another time … pid_t pid = ExecFork(); if(pid < 0) { - apt_error(std::cerr, statusfd, fd, "Fork failed for %s to check %s", Args[0], File.c_str()); + apt_error(std::cerr, statusfd, fd, "Fork failed for %s to check %s", Args[0].c_str(), File.c_str()); local_exit(EINTERNAL); } if(pid == 0) { if (statusfd != -1) dup2(fd[1], statusfd); - execvp(Args[0], (char **) &Args[0]); - apt_error(std::cerr, statusfd, fd, "Couldn't execute %s to check %s", Args[0], File.c_str()); + execvp(cArgs[0], (char **) &cArgs[0]); + apt_error(std::cerr, statusfd, fd, "Couldn't execute %s to check %s", Args[0].c_str(), File.c_str()); local_exit(EINTERNAL); } |