diff options
| -rw-r--r-- | src/Core/Unix/CoreUnix.cpp | 98 |
1 files changed, 96 insertions, 2 deletions
diff --git a/src/Core/Unix/CoreUnix.cpp b/src/Core/Unix/CoreUnix.cpp index a6485208..2dac4cb5 100644 --- a/src/Core/Unix/CoreUnix.cpp +++ b/src/Core/Unix/CoreUnix.cpp @@ -24,6 +24,11 @@ namespace VeraCrypt { +#ifdef TC_LINUX + static string GetTmpUser (); + static bool SamePath (const string& path1, const string& path2); +#endif + CoreUnix::CoreUnix () { signal (SIGPIPE, SIG_IGN); @@ -355,9 +360,98 @@ namespace VeraCrypt string CoreUnix::GetTempDirectory () const { - char *envDir = getenv ("TMPDIR"); - return envDir ? envDir : "/tmp"; + const char *tmpdir = getenv ("TMPDIR"); + string envDir = tmpdir ? tmpdir : "/tmp"; + +#ifdef TC_LINUX + /* + * If pam_tmpdir.so is in use, a different temporary directory is + * allocated for each user ID. We need to mount to the directory used + * by the non-root user. + */ + if (getuid () == 0 && envDir.size () >= 2 + && envDir.substr (envDir.size () - 2) == "/0") { + string tmpuser = GetTmpUser (); + if (SamePath (envDir, tmpuser + "/0")) { + /* Substitute the sudo'ing user for 0 */ + char uid[40]; + FILE *fp = fopen ("/proc/self/loginuid", "r"); + if (fp != NULL) { + if (fgets (uid, sizeof (uid), fp) != nullptr) { + envDir = tmpuser + "/" + uid; + } + fclose (fp); + } + } + } +#endif + + return envDir; + } + +#ifdef TC_LINUX + static string GetTmpUser () + { + string tmpuser = "/tmp/user"; + FILE *fp = fopen ("/etc/security/tmpdir.conf", "r"); + if (fp == NULL) { + return tmpuser; + } + while (true) { + /* Parses the same way as pam_tmpdir */ + char line[1024]; + if (fgets (line, sizeof (line), fp) == nullptr) { + break; + } + if (line[0] == '#') { + continue; + } + size_t len = strlen (line); + if (len > 0 && line[len-1] == '\n') { + line[len-1] = '\0'; + } + char *eq = strchr (line, '='); + if (eq == nullptr) { + continue; + } + *eq = '\0'; + const char *key = line; + const char *value = eq + 1; + if (strcmp (key, "tmpdir") == 0) { + tmpuser = value; + break; + } + } + fclose (fp); + return tmpuser; + } + + static bool SamePath (const string& path1, const string& path2) + { + size_t i1 = 0; + size_t i2 = 0; + while (i1 < path1.size () && i2 < path2.size ()) { + if (path1[i1] != path2[i2]) { + return false; + } + /* Any two substrings consisting entirely of slashes compare equal */ + if (path1[i1] == '/') { + while (i1 < path1.size () && path1[i1] == '/') { + ++i1; + } + while (i2 < path2.size () && path2[i2] == '/') { + ++i2; + } + } + else + { + ++i1; + ++i2; + } + } + return (i1 == path1.size () && i2 == path2.size ()); } +#endif bool CoreUnix::IsMountPointAvailable (const DirectoryPath &mountPoint) const { |