X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/99ed26d32226f0dffe5a37fb78c5588f9d9ecfd5..46c4043d741cb2c1d54e7f5bfaa234f1b7580f6c:/apt-pkg/contrib/gpgv.cc?ds=sidebyside diff --git a/apt-pkg/contrib/gpgv.cc b/apt-pkg/contrib/gpgv.cc index 9760bd21f..0929ae0e2 100644 --- a/apt-pkg/contrib/gpgv.cc +++ b/apt-pkg/contrib/gpgv.cc @@ -2,102 +2,82 @@ // Include Files /*{{{*/ #include -#include -#include -#include -#include -#include -#include +#include +#include +#include +#include +#include + +#include #include +#include #include +#include +#include +#include +#include -#include -#include -#include -#include +#include +#include +#include +#include #include /*}}}*/ - -using namespace std; - -// RunGPGV - returns the command needed for verify /*{{{*/ +static char * GenerateTemporaryFileTemplate(const char *basename) /*{{{*/ +{ + std::string out; + std::string tmpdir = GetTempDir(); + strprintf(out, "%s/%s.XXXXXX", tmpdir.c_str(), basename); + return strdup(out.c_str()); +} + /*}}}*/ +// ExecGPGV - returns the command needed for verify /*{{{*/ // --------------------------------------------------------------------- -/* Generating the commandline for calling gpgv is somehow complicated as - we need to add multiple keyrings and user supplied options. */ +/* Generating the commandline for calling gpg is somehow complicated as + we need to add multiple keyrings and user supplied options. + Also, as gpg has no options to enforce a certain reduced style of + clear-signed files (=the complete content of the file is signed and + the content isn't encoded) we do a divide and conquer approach here + and split up the clear-signed file in message and signature for gpg. + 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. +*/ void ExecGPGV(std::string const &File, std::string const &FileGPG, - int const &statusfd, int fd[2]) + int const &statusfd, int fd[2], std::string const &key) { #define EINTERNAL 111 - - if (File == FileGPG) - { - #define SIGMSG "-----BEGIN PGP SIGNED MESSAGE-----\n" - char buffer[sizeof(SIGMSG)]; - FILE* gpg = fopen(File.c_str(), "r"); - if (gpg == NULL) - { - ioprintf(std::cerr, _("Could not open file %s"), File.c_str()); - exit(EINTERNAL); - } - char const * const test = fgets(buffer, sizeof(buffer), gpg); - fclose(gpg); - if (test == NULL || strcmp(buffer, SIGMSG) != 0) - { - ioprintf(std::cerr, _("File %s doesn't start with a clearsigned message"), File.c_str()); - exit(EINTERNAL); - } - #undef SIGMSG - } - - - string const gpgvpath = _config->Find("Dir::Bin::gpg", "/usr/bin/gpgv"); - // FIXME: remove support for deprecated APT::GPGV setting - string const trustedFile = _config->Find("APT::GPGV::TrustedKeyring", _config->FindFile("Dir::Etc::Trusted")); - string const trustedPath = _config->FindDir("Dir::Etc::TrustedParts"); + std::string const aptkey = _config->FindFile("Dir::Bin::apt-key", "/usr/bin/apt-key"); bool const Debug = _config->FindB("Debug::Acquire::gpgv", false); - if (Debug == true) - { - std::clog << "gpgv path: " << gpgvpath << std::endl; - std::clog << "Keyring file: " << trustedFile << std::endl; - std::clog << "Keyring path: " << trustedPath << std::endl; - } - - std::vector keyrings; - if (DirectoryExists(trustedPath)) - keyrings = GetListOfFilesInDir(trustedPath, "gpg", false, true); - if (RealFileExists(trustedFile) == true) - keyrings.push_back(trustedFile); - std::vector Args; - Args.reserve(30); + Args.reserve(10); - if (keyrings.empty() == true) + Args.push_back(aptkey.c_str()); + Args.push_back("--quiet"); + Args.push_back("--readonly"); + if (key.empty() == false) { - // TRANSLATOR: %s is the trusted keyring parts directory - ioprintf(std::cerr, _("No keyring installed in %s."), - _config->FindDir("Dir::Etc::TrustedParts").c_str()); - exit(EINTERNAL); + if (key[0] == '/') + { + Args.push_back("--keyring"); + Args.push_back(key.c_str()); + } + else + { + Args.push_back("--keyid"); + Args.push_back(key.c_str()); + } } + Args.push_back("verify"); - Args.push_back(gpgvpath.c_str()); - Args.push_back("--ignore-time-conflict"); - + char statusfdstr[10]; if (statusfd != -1) { Args.push_back("--status-fd"); - char fd[10]; - snprintf(fd, sizeof(fd), "%i", statusfd); - Args.push_back(fd); - } - - for (vector::const_iterator K = keyrings.begin(); - K != keyrings.end(); ++K) - { - Args.push_back("--keyring"); - Args.push_back(K->c_str()); + snprintf(statusfdstr, sizeof(statusfdstr), "%i", statusfd); + Args.push_back(statusfdstr); } Configuration::Item const *Opts; @@ -113,14 +93,62 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, } } - Args.push_back(FileGPG.c_str()); - if (FileGPG != File) + enum { DETACHED, CLEARSIGNED } releaseSignature = (FileGPG != File) ? DETACHED : CLEARSIGNED; + std::vector dataHeader; + char * sig = NULL; + char * data = NULL; + + if (releaseSignature == DETACHED) + { + Args.push_back(FileGPG.c_str()); Args.push_back(File.c_str()); + } + else // clear-signed file + { + sig = GenerateTemporaryFileTemplate("apt.sig"); + data = GenerateTemporaryFileTemplate("apt.data"); + if (sig == NULL || data == NULL) + { + ioprintf(std::cerr, "Couldn't create tempfile names for splitting up %s", File.c_str()); + exit(EINTERNAL); + } + + int const sigFd = mkstemp(sig); + int const dataFd = mkstemp(data); + if (sigFd == -1 || dataFd == -1) + { + if (dataFd != -1) + unlink(sig); + if (sigFd != -1) + unlink(data); + ioprintf(std::cerr, "Couldn't create tempfiles for splitting up %s", File.c_str()); + exit(EINTERNAL); + } + + FileFd signature; + signature.OpenDescriptor(sigFd, FileFd::WriteOnly, true); + FileFd message; + message.OpenDescriptor(dataFd, FileFd::WriteOnly, true); + + if (signature.Failed() == true || message.Failed() == true || + SplitClearSignedFile(File, &message, &dataHeader, &signature) == false) + { + if (dataFd != -1) + unlink(sig); + if (sigFd != -1) + unlink(data); + ioprintf(std::cerr, "Splitting up %s into data and signature failed", File.c_str()); + exit(112); + } + Args.push_back(sig); + Args.push_back(data); + } + Args.push_back(NULL); if (Debug == true) { - std::clog << "Preparing to exec: " << gpgvpath; + std::clog << "Preparing to exec: "; for (std::vector::const_iterator a = Args.begin(); *a != NULL; ++a) std::clog << " " << *a; std::clog << std::endl; @@ -128,11 +156,13 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, if (statusfd != -1) { - int const nullfd = open("/dev/null", O_RDONLY); + int const nullfd = open("/dev/null", O_WRONLY); close(fd[0]); // Redirect output to /dev/null; we read from the status fd - dup2(nullfd, STDOUT_FILENO); - dup2(nullfd, STDERR_FILENO); + if (statusfd != STDOUT_FILENO) + dup2(nullfd, STDOUT_FILENO); + if (statusfd != STDERR_FILENO) + dup2(nullfd, STDERR_FILENO); // Redirect the pipe to the status fd (3) dup2(fd[1], statusfd); @@ -141,8 +171,200 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG, putenv((char *)"LC_MESSAGES="); } - execvp(gpgvpath.c_str(), (char **) &Args[0]); - ioprintf(std::cerr, "Couldn't execute %s to check %s", Args[0], File.c_str()); - exit(EINTERNAL); + if (releaseSignature == DETACHED) + { + execvp(Args[0], (char **) &Args[0]); + ioprintf(std::cerr, "Couldn't execute %s to check %s", Args[0], File.c_str()); + exit(EINTERNAL); + } + else + { +//#define UNLINK_EXIT(X) exit(X) +#define UNLINK_EXIT(X) unlink(sig);unlink(data);exit(X) + + // for clear-signed files 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) { + ioprintf(std::cerr, "Fork failed for %s to check %s", Args[0], File.c_str()); + UNLINK_EXIT(EINTERNAL); + } + if(pid == 0) + { + if (statusfd != -1) + dup2(fd[1], statusfd); + execvp(Args[0], (char **) &Args[0]); + ioprintf(std::cerr, "Couldn't execute %s to check %s", Args[0], File.c_str()); + UNLINK_EXIT(EINTERNAL); + } + + // Wait and collect the error code - taken from WaitPid as we need the exact Status + int Status; + while (waitpid(pid,&Status,0) != pid) + { + if (errno == EINTR) + continue; + ioprintf(std::cerr, _("Waited for %s but it wasn't there"), "apt-key"); + UNLINK_EXIT(EINTERNAL); + } +#undef UNLINK_EXIT + // we don't need the files any longer + unlink(sig); + unlink(data); + free(sig); + free(data); + + // check if it exit'ed normally … + if (WIFEXITED(Status) == false) + { + ioprintf(std::cerr, _("Sub-process %s exited unexpectedly"), "apt-key"); + exit(EINTERNAL); + } + + // … and with a good exit code + if (WEXITSTATUS(Status) != 0) + { + ioprintf(std::cerr, _("Sub-process %s returned an error code (%u)"), "apt-key", WEXITSTATUS(Status)); + exit(WEXITSTATUS(Status)); + } + + // everything fine + exit(0); + } + exit(EINTERNAL); // unreachable safe-guard +} + /*}}}*/ +// SplitClearSignedFile - split message into data/signature /*{{{*/ +bool SplitClearSignedFile(std::string const &InFile, FileFd * const ContentFile, + std::vector * const ContentHeader, FileFd * const SignatureFile) +{ + FILE *in = fopen(InFile.c_str(), "r"); + if (in == NULL) + return _error->Errno("fopen", "can not open %s", InFile.c_str()); + + bool found_message_start = false; + bool found_message_end = false; + bool skip_until_empty_line = false; + bool found_signature = false; + bool first_line = true; + + char *buf = NULL; + size_t buf_size = 0; + while (getline(&buf, &buf_size, in) != -1) + { + _strrstrip(buf); + if (found_message_start == false) + { + if (strcmp(buf, "-----BEGIN PGP SIGNED MESSAGE-----") == 0) + { + found_message_start = true; + skip_until_empty_line = true; + } + } + else if (skip_until_empty_line == true) + { + if (strlen(buf) == 0) + skip_until_empty_line = false; + // save "Hash" Armor Headers, others aren't allowed + else if (ContentHeader != NULL && strncmp(buf, "Hash: ", strlen("Hash: ")) == 0) + ContentHeader->push_back(buf); + } + else if (found_signature == false) + { + if (strcmp(buf, "-----BEGIN PGP SIGNATURE-----") == 0) + { + found_signature = true; + found_message_end = true; + if (SignatureFile != NULL) + { + SignatureFile->Write(buf, strlen(buf)); + SignatureFile->Write("\n", 1); + } + } + else if (found_message_end == false) // we are in the message block + { + // we don't have any fields which need dash-escaped, + // but implementations are free to encode all lines … + char const * dashfree = buf; + if (strncmp(dashfree, "- ", 2) == 0) + dashfree += 2; + if(first_line == true) // first line does not need a newline + first_line = false; + else if (ContentFile != NULL) + ContentFile->Write("\n", 1); + else + continue; + if (ContentFile != NULL) + ContentFile->Write(dashfree, strlen(dashfree)); + } + } + else if (found_signature == true) + { + if (SignatureFile != NULL) + { + SignatureFile->Write(buf, strlen(buf)); + SignatureFile->Write("\n", 1); + } + if (strcmp(buf, "-----END PGP SIGNATURE-----") == 0) + found_signature = false; // look for other signatures + } + // all the rest is whitespace, unsigned garbage or additional message blocks we ignore + } + fclose(in); + if (buf != NULL) + free(buf); + + if (found_signature == true) + return _error->Error("Signature in file %s wasn't closed", InFile.c_str()); + + // if we haven't found any of them, this an unsigned file, + // so don't generate an error, but splitting was unsuccessful none-the-less + if (first_line == true && found_message_start == false && found_message_end == false) + return false; + // otherwise one missing indicates a syntax error + else if (first_line == true || found_message_start == false || found_message_end == false) + return _error->Error("Splitting of file %s failed as it doesn't contain all expected parts %i %i %i", InFile.c_str(), first_line, found_message_start, found_message_end); + + return true; +} + /*}}}*/ +bool OpenMaybeClearSignedFile(std::string const &ClearSignedFileName, FileFd &MessageFile) /*{{{*/ +{ + char * const message = GenerateTemporaryFileTemplate("fileutl.message"); + int const messageFd = mkstemp(message); + if (messageFd == -1) + { + free(message); + return _error->Errno("mkstemp", "Couldn't create temporary file to work with %s", ClearSignedFileName.c_str()); + } + // we have the fd, thats enough for us + unlink(message); + free(message); + + MessageFile.OpenDescriptor(messageFd, FileFd::ReadWrite | FileFd::BufferedWrite, true); + if (MessageFile.Failed() == true) + return _error->Error("Couldn't open temporary file to work with %s", ClearSignedFileName.c_str()); + + _error->PushToStack(); + bool const splitDone = SplitClearSignedFile(ClearSignedFileName, &MessageFile, NULL, NULL); + bool const errorDone = _error->PendingError(); + _error->MergeWithStack(); + if (splitDone == false) + { + MessageFile.Close(); + + if (errorDone == true) + return false; + + // we deal with an unsigned file + MessageFile.Open(ClearSignedFileName, FileFd::ReadOnly); + } + else // clear-signed + { + if (MessageFile.Seek(0) == false) + return _error->Errno("lseek", "Unable to seek back in message for file %s", ClearSignedFileName.c_str()); + } + + return MessageFile.Failed() == false; } /*}}}*/