nss: use secure_getenv for behaviour-modifying booleans (#6817)

Follow up for fe102d6ab15731a199a7ea9f38c4f68d8959f86c.

diff --git a/src/basic/env-util.c b/src/basic/env-util.c
index 56e7b6f..d72940a 100644 (file)
--- a/src/basic/env-util.c
+++ b/src/basic/env-util.c
@@ -769,6 +769,16 @@ int getenv_bool(const char *p) {
         return parse_boolean(e);
 }
 
+int getenv_bool_secure(const char *p) {
+        const char *e;
+
+        e = secure_getenv(p);
+        if (!e)
+                return -ENXIO;
+
+        return parse_boolean(e);
+}
+
 int serialize_environment(FILE *f, char **environment) {
         char **e;
 

diff --git a/src/basic/env-util.h b/src/basic/env-util.h
index e88fa6a..d5da8cd 100644 (file)
--- a/src/basic/env-util.h
+++ b/src/basic/env-util.h
@@ -61,6 +61,7 @@ char *strv_env_get_n(char **l, const char *name, size_t k, unsigned flags) _pure
 char *strv_env_get(char **x, const char *n) _pure_;
 
 int getenv_bool(const char *p);
+int getenv_bool_secure(const char *p);
 
 int serialize_environment(FILE *f, char **environment);
 int deserialize_environment(char ***environment, const char *line);

diff --git a/src/nss-mymachines/nss-mymachines.c b/src/nss-mymachines/nss-mymachines.c
index ea90953..6e46885 100644 (file)
--- a/src/nss-mymachines/nss-mymachines.c
+++ b/src/nss-mymachines/nss-mymachines.c
@@ -435,7 +435,7 @@ enum nss_status _nss_mymachines_getpwnam_r(
         if (!machine_name_is_valid(machine))
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0)
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0)
                 /* Make sure we can't deadlock if we are invoked by dbus-daemon. This way, it won't be able to resolve
                  * these UIDs, but that should be unproblematic as containers should never be able to connect to a bus
                  * running on the host. */
@@ -519,7 +519,7 @@ enum nss_status _nss_mymachines_getpwuid_r(
         if (uid < HOST_UID_LIMIT)
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0)
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0)
                 goto not_found;
 
         r = sd_bus_open_system(&bus);
@@ -613,7 +613,7 @@ enum nss_status _nss_mymachines_getgrnam_r(
         if (!machine_name_is_valid(machine))
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0)
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0)
                 goto not_found;
 
         r = sd_bus_open_system(&bus);
@@ -691,7 +691,7 @@ enum nss_status _nss_mymachines_getgrgid_r(
         if (gid < HOST_GID_LIMIT)
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0)
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0)
                 goto not_found;
 
         r = sd_bus_open_system(&bus);

diff --git a/src/nss-systemd/nss-systemd.c b/src/nss-systemd/nss-systemd.c
index 37745b3..dcb32e1 100644 (file)
--- a/src/nss-systemd/nss-systemd.c
+++ b/src/nss-systemd/nss-systemd.c
@@ -129,7 +129,7 @@ enum nss_status _nss_systemd_getpwnam_r(
                 goto not_found;
 
         /* Synthesize entries for the root and nobody users, in case they are missing in /etc/passwd */
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) {
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) {
                 if (streq(name, root_passwd.pw_name)) {
                         *pwd = root_passwd;
                         *errnop = 0;
@@ -143,10 +143,10 @@ enum nss_status _nss_systemd_getpwnam_r(
         }
 
         /* Make sure that we don't go in circles when allocating a dynamic UID by checking our own database */
-        if (getenv_bool("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
+        if (getenv_bool_secure("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0) {
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0) {
 
                 /* Access the dynamic UID allocation directly if we are called from dbus-daemon, see above. */
                 r = direct_lookup_name(name, (uid_t*) &translated);
@@ -233,7 +233,7 @@ enum nss_status _nss_systemd_getpwuid_r(
                 goto not_found;
 
         /* Synthesize data for the root user and for nobody in case they are missing from /etc/passwd */
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) {
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) {
                 if (uid == root_passwd.pw_uid) {
                         *pwd = root_passwd;
                         *errnop = 0;
@@ -249,10 +249,10 @@ enum nss_status _nss_systemd_getpwuid_r(
         if (uid <= SYSTEM_UID_MAX)
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
+        if (getenv_bool_secure("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0) {
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0) {
 
                 r = direct_lookup_uid(uid, &direct);
                 if (r == -ENOENT)
@@ -335,7 +335,7 @@ enum nss_status _nss_systemd_getgrnam_r(
                 goto not_found;
 
         /* Synthesize records for root and nobody, in case they are missing form /etc/group */
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) {
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) {
                 if (streq(name, root_group.gr_name)) {
                         *gr = root_group;
                         *errnop = 0;
@@ -348,10 +348,10 @@ enum nss_status _nss_systemd_getgrnam_r(
                 }
         }
 
-        if (getenv_bool("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
+        if (getenv_bool_secure("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0) {
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0) {
 
                 /* Access the dynamic GID allocation directly if we are called from dbus-daemon, see above. */
                 r = direct_lookup_name(name, (uid_t*) &translated);
@@ -436,7 +436,7 @@ enum nss_status _nss_systemd_getgrgid_r(
                 goto not_found;
 
         /* Synthesize records for root and nobody, in case they are missing from /etc/group */
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) {
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_SYNTHETIC") <= 0) {
                 if (gid == root_group.gr_gid) {
                         *gr = root_group;
                         *errnop = 0;
@@ -452,10 +452,10 @@ enum nss_status _nss_systemd_getgrgid_r(
         if (gid <= SYSTEM_GID_MAX)
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
+        if (getenv_bool_secure("SYSTEMD_NSS_DYNAMIC_BYPASS") > 0)
                 goto not_found;
 
-        if (getenv_bool("SYSTEMD_NSS_BYPASS_BUS") > 0) {
+        if (getenv_bool_secure("SYSTEMD_NSS_BYPASS_BUS") > 0) {
 
                 r = direct_lookup_uid(gid, &direct);
                 if (r == -ENOENT)