X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fcapability.c;h=65d7e038a7a39d305352bf9b4de8d865085a79da;hp=58270ad8cc250e1c14a45e4be4acb901628e5b3a;hb=080bfdbb8e9f3d23594b101d7f50e7e2f9e4699b;hpb=ed617ec21117874094ae7eeca978e2897da36ba5

diff --git a/src/shared/capability.c b/src/shared/capability.c
index 58270ad8c..65d7e038a 100644
--- a/src/shared/capability.c
+++ b/src/shared/capability.c
@@ -85,9 +85,9 @@ unsigned long cap_last_cap(void) {
 }
 
 int capability_bounding_set_drop(uint64_t drop, bool right_now) {
-        unsigned long i;
-        _cleanup_cap_free_ cap_t after_cap = NULL, temp_cap = NULL;
+        _cleanup_cap_free_ cap_t after_cap = NULL;
         cap_flag_value_t fv;
+        unsigned long i;
         int r;
 
         /* If we are run as PID 1 we will lack CAP_SETPCAP by default
@@ -103,6 +103,7 @@ int capability_bounding_set_drop(uint64_t drop, bool right_now) {
                 return -errno;
 
         if (fv != CAP_SET) {
+                _cleanup_cap_free_ cap_t temp_cap = NULL;
                 static const cap_value_t v = CAP_SETPCAP;
 
                 temp_cap = cap_dup(after_cap);
@@ -217,8 +218,6 @@ int capability_bounding_set_drop_usermode(uint64_t drop) {
 int drop_privileges(uid_t uid, gid_t gid, uint64_t keep_capabilities) {
 
         _cleanup_cap_free_ cap_t d = NULL;
-        cap_value_t bits[sizeof(keep_capabilities)*8];
-        unsigned i, j = 0;
         int r;
 
         /* Unfortunately we cannot leave privilege dropping to PID 1
@@ -228,58 +227,65 @@ int drop_privileges(uid_t uid, gid_t gid, uint64_t keep_capabilities) {
          * binary has the capability configured in the file system,
          * which we want to avoid. */
 
-        if (setresgid(gid, gid, gid) < 0) {
-                log_error("Failed change group ID: %m");
-                return -errno;
-        }
+        if (setresgid(gid, gid, gid) < 0)
+                return log_error_errno(errno, "Failed to change group ID: %m");
 
-        if (setgroups(0, NULL) < 0) {
-                log_error("Failed to drop auxiliary groups list: %m");
-                return -errno;
-        }
+        if (setgroups(0, NULL) < 0)
+                return log_error_errno(errno, "Failed to drop auxiliary groups list: %m");
 
-        if (prctl(PR_SET_KEEPCAPS, 1) < 0) {
-                log_error("Failed to enable keep capabilities flag: %m");
-                return -errno;
-        }
+        if (prctl(PR_SET_KEEPCAPS, 1) < 0)
+                return log_error_errno(errno, "Failed to enable keep capabilities flag: %m");
 
         r = setresuid(uid, uid, uid);
-        if (r < 0) {
-                log_error("Failed change user ID: %m");
-                return -errno;
-        }
+        if (r < 0)
+                return log_error_errno(errno, "Failed to change user ID: %m");
 
-        if (prctl(PR_SET_KEEPCAPS, 0) < 0) {
-                log_error("Failed to disable keep capabilities flag: %m");
-                return -errno;
-        }
+        if (prctl(PR_SET_KEEPCAPS, 0) < 0)
+                return log_error_errno(errno, "Failed to disable keep capabilities flag: %m");
 
         r = capability_bounding_set_drop(~keep_capabilities, true);
-        if (r < 0) {
-                log_error("Failed to drop capabilities: %s", strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Failed to drop capabilities: %m");
 
         d = cap_init();
         if (!d)
                 return log_oom();
 
-        for (i = 0; i < sizeof(keep_capabilities)*8; i++)
-                if (keep_capabilities & (1ULL << i))
-                        bits[j++] = i;
-
         if (keep_capabilities) {
+                cap_value_t bits[sizeof(keep_capabilities)*8];
+                unsigned i, j = 0;
+
+                for (i = 0; i < sizeof(keep_capabilities)*8; i++)
+                        if (keep_capabilities & (1ULL << i))
+                                bits[j++] = i;
+
                 if (cap_set_flag(d, CAP_EFFECTIVE, j, bits, CAP_SET) < 0 ||
                     cap_set_flag(d, CAP_PERMITTED, j, bits, CAP_SET) < 0) {
-                        log_error("Failed to enable capabilities bits: %m");
+                        log_error_errno(errno, "Failed to enable capabilities bits: %m");
                         return -errno;
                 }
         }
 
-        if (cap_set_proc(d) < 0) {
-                log_error("Failed to increase capabilities: %m");
+        if (cap_set_proc(d) < 0)
+                return log_error_errno(errno, "Failed to increase capabilities: %m");
+
+        return 0;
+}
+
+int drop_capability(cap_value_t cv) {
+        _cleanup_cap_free_ cap_t tmp_cap = NULL;
+
+        tmp_cap = cap_get_proc();
+        if (!tmp_cap)
+                return -errno;
+
+        if ((cap_set_flag(tmp_cap, CAP_INHERITABLE, 1, &cv, CAP_CLEAR) < 0) ||
+            (cap_set_flag(tmp_cap, CAP_PERMITTED, 1, &cv, CAP_CLEAR) < 0) ||
+            (cap_set_flag(tmp_cap, CAP_EFFECTIVE, 1, &cv, CAP_CLEAR) < 0))
+                return -errno;
+
+        if (cap_set_proc(tmp_cap) < 0)
                 return -errno;
-        }
 
         return 0;
 }