#include <signal.h>
#include <errno.h>
#include <glob.h>
+#include <pwd.h>
+#include <grp.h>
#include <set>
#include <algorithm>
#include <bzlib.h>
#endif
#ifdef HAVE_LZMA
- #include <stdint.h>
#include <lzma.h>
#endif
+#include <endian.h>
+#include <stdint.h>
-#ifdef WORDS_BIGENDIAN
-#include <inttypes.h>
+#if __gnu_linux__
+#include <sys/prctl.h>
#endif
#include <apti18n.h>
}
/*}}}*/
+
+// StartsWithGPGClearTextSignature - Check if a file is Pgp/GPG clearsigned /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool StartsWithGPGClearTextSignature(string const &FileName)
+{
+ static const char* SIGMSG = "-----BEGIN PGP SIGNED MESSAGE-----\n";
+ char buffer[strlen(SIGMSG)+1];
+ FILE* gpg = fopen(FileName.c_str(), "r");
+ if (gpg == NULL)
+ return false;
+
+ char const * const test = fgets(buffer, sizeof(buffer), gpg);
+ fclose(gpg);
+ if (test == NULL || strcmp(buffer, SIGMSG) != 0)
+ return false;
+
+ return true;
+}
+
+
class FileFdPrivate { /*{{{*/
public:
#ifdef HAVE_ZLIB
bool eof;
bool compressing;
- LZMAFILE() : file(NULL), eof(false), compressing(false) {}
+ LZMAFILE() : file(NULL), eof(false), compressing(false) { buffer[0] = '\0'; }
~LZMAFILE() {
if (compressing == true)
{
if (d->lzma == NULL)
d->lzma = new FileFdPrivate::LZMAFILE;
d->lzma->file = (FILE*) compress_struct;
- d->lzma->stream = LZMA_STREAM_INIT;
+ lzma_stream tmp_stream = LZMA_STREAM_INIT;
+ d->lzma->stream = tmp_stream;
if ((Mode & ReadWrite) == ReadWrite)
return FileFdError("ReadWrite mode is not supported for file %s", FileName.c_str());
int err;
char const * const errmsg = BZ2_bzerror(d->bz2, &err);
if (err != BZ_IO_ERROR)
- return FileFdError("BZ2_bzread: %s (%d: %s)", _("Read error"), err, errmsg);
+ return FileFdError("BZ2_bzread: %s %s (%d: %s)", FileName.c_str(), _("Read error"), err, errmsg);
}
#endif
#ifdef HAVE_LZMA
// higher-level code will generate more meaningful messages,
// even translated this would be meaningless for users
return _error->Errno("fstat", "Unable to determine %s for fd %i", msg, iFd);
- ispipe = S_ISFIFO(Buf.st_mode);
+ if (FileName.empty() == false)
+ ispipe = S_ISFIFO(Buf.st_mode);
}
// for compressor pipes st_size is undefined and at 'best' zero
FileFdErrno("lseek","Unable to seek to end of gzipped file");
return 0;
}
- size = 0;
+ uint32_t size = 0;
if (read(iFd, &size, 4) != 4)
{
FileFdErrno("read","Unable to read original size of gzipped file");
return 0;
}
-
-#ifdef WORDS_BIGENDIAN
- uint32_t tmp_size = size;
- uint8_t const * const p = (uint8_t const * const) &tmp_size;
- tmp_size = (p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0];
- size = tmp_size;
-#endif
+ size = le32toh(size);
if (lseek(iFd, oldPos, SEEK_SET) < 0)
{
int Pipe[2] = {-1, -1};
if(pipe(Pipe) != 0)
- {
return _error->Errno("pipe", _("Failed to create subprocess IPC"));
- return NULL;
- }
+
std::set<int> keep_fds;
keep_fds.insert(Pipe[0]);
keep_fds.insert(Pipe[1]);
return true;
}
+
+bool DropPrivs()
+{
+ // uid will be 0 in the end, but gid might be different anyway
+ uid_t old_uid = getuid();
+ gid_t old_gid = getgid();
+
+ if (old_uid != 0)
+ return true;
+ if(_config->FindB("Debug::NoDropPrivs", false) == true)
+ return true;
+
+ const std::string toUser = _config->Find("APT::Sandbox::User", "_apt");
+ struct passwd *pw = getpwnam(toUser.c_str());
+ if (pw == NULL)
+ return _error->Error("No user %s, can not drop rights", toUser.c_str());
+
+#if __gnu_linux__
+ // see prctl(2), needs linux3.5
+ int ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0,0, 0);
+ if(ret < 0)
+ _error->Warning("PR_SET_NO_NEW_PRIVS failed with %i", ret);
+#endif
+ // Do not change the order here, it might break things
+ if (setgroups(1, &pw->pw_gid))
+ return _error->Errno("setgroups", "Failed to setgroups");
+
+ if (setegid(pw->pw_gid) != 0)
+ return _error->Errno("setegid", "Failed to setegid");
+
+ if (setgid(pw->pw_gid) != 0)
+ return _error->Errno("setgid", "Failed to setgid");
+
+ if (setuid(pw->pw_uid) != 0)
+ return _error->Errno("setuid", "Failed to setuid");
+
+ // the seteuid() is probably uneeded (at least thats what the linux
+ // man-page says about setuid(2)) but we cargo culted it anyway
+ if (seteuid(pw->pw_uid) != 0)
+ return _error->Errno("seteuid", "Failed to seteuid");
+
+ // Verify that the user has only a single group, and the correct one
+ gid_t groups[1];
+ if (getgroups(1, groups) != 1)
+ return _error->Errno("getgroups", "Could not get new groups");
+ if (groups[0] != pw->pw_gid)
+ return _error->Error("Could not switch group");
+
+ // Verify that gid, egid, uid, and euid changed
+ if (getgid() != pw->pw_gid)
+ return _error->Error("Could not switch group");
+ if (getegid() != pw->pw_gid)
+ return _error->Error("Could not switch effective group");
+ if (getuid() != pw->pw_uid)
+ return _error->Error("Could not switch user");
+ if (geteuid() != pw->pw_uid)
+ return _error->Error("Could not switch effective user");
+
+#ifdef HAVE_GETRESUID
+ // verify that the saved set-user-id was changed as well
+ uid_t ruid = 0;
+ uid_t euid = 0;
+ uid_t suid = 0;
+ if (getresuid(&ruid, &euid, &suid))
+ return _error->Errno("getresuid", "Could not get saved set-user-ID");
+ if (suid != pw->pw_uid)
+ return _error->Error("Could not switch saved set-user-ID");
+#endif
+
+#ifdef HAVE_GETRESGID
+ // verify that the saved set-group-id was changed as well
+ gid_t rgid = 0;
+ gid_t egid = 0;
+ gid_t sgid = 0;
+ if (getresgid(&rgid, &egid, &sgid))
+ return _error->Errno("getresuid", "Could not get saved set-group-ID");
+ if (sgid != pw->pw_gid)
+ return _error->Error("Could not switch saved set-group-ID");
+#endif
+
+ // Check that uid and gid changes do not work anymore
+ if (pw->pw_gid != old_gid && (setgid(old_gid) != -1 || setegid(old_gid) != -1))
+ return _error->Error("Could restore a gid to root, privilege dropping did not work");
+
+ if (pw->pw_uid != old_uid && (setuid(old_uid) != -1 || seteuid(old_uid) != -1))
+ return _error->Error("Could restore a uid to root, privilege dropping did not work");
+
+ return true;
+}
projects / apt.git / blobdiff