commit 54d7d31cba84232b50fef4287951b2c4bfa746c2 Author: Jérémy Bobbio lunar@debian.org Date: Tue Jun 14 12:18:32 2011 -0400
Make ControlSocketsGroupWritable work with User.
Original message from bug3393:
check_private_dir() to ensure that ControlSocketsGroupWritable is safe to use. Unfortunately, check_private_dir() only checks against the currently running user… which can be root until privileges are dropped to the user and group configured by the User config option.
The attached patch fixes the issue by adding a new effective_user argument to check_private_dir() and updating the callers. It might not be the best way to fix the issue, but it did in my tests.
(Code by lunar; changelog by nickm) --- src/common/util.c | 33 ++++++++++++++++++++++++++------- src/common/util.h | 3 ++- src/or/config.c | 6 ++++-- src/or/connection.c | 2 +- src/or/geoip.c | 6 +++--- src/or/rendservice.c | 2 +- src/or/rephist.c | 4 ++-- src/or/router.c | 4 ++-- 8 files changed, 41 insertions(+), 19 deletions(-)
diff --git a/src/common/util.c b/src/common/util.c index 6f323dd..36aa9cc 100644 --- a/src/common/util.c +++ b/src/common/util.c @@ -1677,15 +1677,20 @@ file_status(const char *fname) * is group-readable, but in all cases we create the directory mode 0700. * If CPD_CHECK_MODE_ONLY is set, then we don't alter the directory permissions * if they are too permissive: we just return -1. + * When effective_user is not NULL, check permissions against the given user and + * its primary group. */ int -check_private_dir(const char *dirname, cpd_check_t check) +check_private_dir(const char *dirname, cpd_check_t check, const char *effective_user) { int r; struct stat st; char *f; #ifndef MS_WINDOWS int mask; + struct passwd *pw = NULL; + uid_t running_uid; + gid_t running_gid; #endif
tor_assert(dirname); @@ -1724,33 +1729,47 @@ check_private_dir(const char *dirname, cpd_check_t check) return -1; } #ifndef MS_WINDOWS - if (st.st_uid != getuid()) { + if (effective_user) { + /* Lookup the user and group information, if we have a problem, bail out. */ + pw = getpwnam(effective_user); + if (pw == NULL) { + log_warn(LD_CONFIG, "Error setting configured user: %s not found", effective_user); + return -1; + } + running_uid = pw->pw_uid; + running_gid = pw->pw_gid; + } else { + running_uid = getuid(); + running_gid = getgid(); + } + + if (st.st_uid != running_uid) { struct passwd *pw = NULL; char *process_ownername = NULL;
- pw = getpwuid(getuid()); + pw = getpwuid(running_uid); process_ownername = pw ? tor_strdup(pw->pw_name) : tor_strdup("<unknown>");
pw = getpwuid(st.st_uid);
log_warn(LD_FS, "%s is not owned by this user (%s, %d) but by " "%s (%d). Perhaps you are running Tor as the wrong user?", - dirname, process_ownername, (int)getuid(), + dirname, process_ownername, (int)running_uid, pw ? pw->pw_name : "<unknown>", (int)st.st_uid);
tor_free(process_ownername); return -1; } - if ((check & CPD_GROUP_OK) && st.st_gid != getgid()) { + if ((check & CPD_GROUP_OK) && st.st_gid != running_gid) { struct group *gr; char *process_groupname = NULL; - gr = getgrgid(getgid()); + gr = getgrgid(running_gid); process_groupname = gr ? tor_strdup(gr->gr_name) : tor_strdup("<unknown>"); gr = getgrgid(st.st_gid);
log_warn(LD_FS, "%s is not owned by this group (%s, %d) but by group " "%s (%d). Are you running Tor as the wrong user?", - dirname, process_groupname, (int)getgid(), + dirname, process_groupname, (int)running_gid, gr ? gr->gr_name : "<unknown>", (int)st.st_gid);
tor_free(process_groupname); diff --git a/src/common/util.h b/src/common/util.h index d657db6..b9db25c 100644 --- a/src/common/util.h +++ b/src/common/util.h @@ -292,7 +292,8 @@ typedef unsigned int cpd_check_t; #define CPD_CHECK 2 #define CPD_GROUP_OK 4 #define CPD_CHECK_MODE_ONLY 8 -int check_private_dir(const char *dirname, cpd_check_t check); +int check_private_dir(const char *dirname, cpd_check_t check, + const char *effective_user); #define OPEN_FLAGS_REPLACE (O_WRONLY|O_CREAT|O_TRUNC) #define OPEN_FLAGS_APPEND (O_WRONLY|O_CREAT|O_APPEND) typedef struct open_file_t open_file_t; diff --git a/src/or/config.c b/src/or/config.c index 44cecf3..8ab23a3 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -1025,7 +1025,8 @@ options_act_reversible(or_options_t *old_options, char **msg)
/* Ensure data directory is private; create if possible. */ if (check_private_dir(options->DataDirectory, - running_tor ? CPD_CREATE : CPD_CHECK)<0) { + running_tor ? CPD_CREATE : CPD_CHECK, + options->User)<0) { tor_asprintf(msg, "Couldn't access/create private data directory "%s"", options->DataDirectory); @@ -1038,7 +1039,8 @@ options_act_reversible(or_options_t *old_options, char **msg) char *fn = tor_malloc(len); tor_snprintf(fn, len, "%s"PATH_SEPARATOR"cached-status", options->DataDirectory); - if (check_private_dir(fn, running_tor ? CPD_CREATE : CPD_CHECK) < 0) { + if (check_private_dir(fn, running_tor ? CPD_CREATE : CPD_CHECK, + options->User) < 0) { tor_asprintf(msg, "Couldn't access/create private data directory "%s"", fn); tor_free(fn); diff --git a/src/or/connection.c b/src/or/connection.c index 3f4ca1d..a9e3a74 100644 --- a/src/or/connection.c +++ b/src/or/connection.c @@ -867,7 +867,7 @@ check_location_for_unix_socket(or_options_t *options, const char *path) if (options->ControlSocketsGroupWritable) flags |= CPD_GROUP_OK;
- if (check_private_dir(p, flags) < 0) { + if (check_private_dir(p, flags, options->User) < 0) { char *escpath, *escdir; escpath = esc_for_log(path); escdir = esc_for_log(p); diff --git a/src/or/geoip.c b/src/or/geoip.c index 5bb2410..c621ea8 100644 --- a/src/or/geoip.c +++ b/src/or/geoip.c @@ -970,7 +970,7 @@ geoip_dirreq_stats_write(time_t now) geoip_remove_old_clients(start_of_dirreq_stats_interval);
statsdir = get_datadir_fname("stats"); - if (check_private_dir(statsdir, CPD_CREATE) < 0) + if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) goto done; filename = get_datadir_fname2("stats", "dirreq-stats"); data_v2 = geoip_get_client_history(GEOIP_CLIENT_NETWORKSTATUS_V2); @@ -1209,7 +1209,7 @@ geoip_bridge_stats_write(time_t now)
/* Write it to disk. */ statsdir = get_datadir_fname("stats"); - if (check_private_dir(statsdir, CPD_CREATE) < 0) + if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) goto done; filename = get_datadir_fname2("stats", "bridge-stats");
@@ -1304,7 +1304,7 @@ geoip_entry_stats_write(time_t now) geoip_remove_old_clients(start_of_entry_stats_interval);
statsdir = get_datadir_fname("stats"); - if (check_private_dir(statsdir, CPD_CREATE) < 0) + if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) goto done; filename = get_datadir_fname2("stats", "entry-stats"); data = geoip_get_client_history(GEOIP_CLIENT_CONNECT); diff --git a/src/or/rendservice.c b/src/or/rendservice.c index a10e43f..d9a9364 100644 --- a/src/or/rendservice.c +++ b/src/or/rendservice.c @@ -569,7 +569,7 @@ rend_service_load_keys(void) s->directory);
/* Check/create directory */ - if (check_private_dir(s->directory, CPD_CREATE) < 0) + if (check_private_dir(s->directory, CPD_CREATE, get_options()->User) < 0) return -1;
/* Load key */ diff --git a/src/or/rephist.c b/src/or/rephist.c index 54593a0..b7341f3 100644 --- a/src/or/rephist.c +++ b/src/or/rephist.c @@ -2307,7 +2307,7 @@ rep_hist_exit_stats_write(time_t now)
/* Try to write to disk. */ statsdir = get_datadir_fname("stats"); - if (check_private_dir(statsdir, CPD_CREATE) < 0) { + if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) { log_warn(LD_HIST, "Unable to create stats/ directory!"); goto done; } @@ -2497,7 +2497,7 @@ rep_hist_buffer_stats_write(time_t now) smartlist_clear(circuits_for_buffer_stats); /* write to file */ statsdir = get_datadir_fname("stats"); - if (check_private_dir(statsdir, CPD_CREATE) < 0) + if (check_private_dir(statsdir, CPD_CREATE, get_options()->User) < 0) goto done; filename = get_datadir_fname2("stats", "buffer-stats"); out = start_writing_to_stdio_file(filename, OPEN_FLAGS_APPEND, diff --git a/src/or/router.c b/src/or/router.c index 68e29bb..2165e6e 100644 --- a/src/or/router.c +++ b/src/or/router.c @@ -533,12 +533,12 @@ init_keys(void) return 0; } /* Make sure DataDirectory exists, and is private. */ - if (check_private_dir(options->DataDirectory, CPD_CREATE)) { + if (check_private_dir(options->DataDirectory, CPD_CREATE, options->User)) { return -1; } /* Check the key directory. */ keydir = get_datadir_fname("keys"); - if (check_private_dir(keydir, CPD_CREATE)) { + if (check_private_dir(keydir, CPD_CREATE, options->User)) { tor_free(keydir); return -1; }