sd-bus: handle ppid=0 more gracefully (which happens for pid=1)

[elogind.git] / src / libelogind / sd-bus / bus-creds.c

diff --git a/src/libelogind/sd-bus/bus-creds.c b/src/libelogind/sd-bus/bus-creds.c
index 33ed85bd6a580e5e93b7bbf0da5c0191e27fba82..9d519c4735e406c1964738a5da4668a26982adfb 100644 (file)
--- a/src/libelogind/sd-bus/bus-creds.c
+++ b/src/libelogind/sd-bus/bus-creds.c
@@ -130,6 +130,12 @@ _public_ uint64_t sd_bus_creds_get_mask(const sd_bus_creds *c) {
         return c->mask;
 }
 
+_public_ uint64_t sd_bus_creds_get_augmented_mask(const sd_bus_creds *c) {
+        assert_return(c, 0);
+
+        return c->augmented;
+}
+
 sd_bus_creds* bus_creds_new(void) {
         sd_bus_creds *c;
 
@@ -286,6 +292,17 @@ _public_ int sd_bus_creds_get_pid(sd_bus_creds *c, pid_t *pid) {
         return 0;
 }
 
+_public_ int sd_bus_creds_get_ppid(sd_bus_creds *c, pid_t *ppid) {
+        assert_return(c, -EINVAL);
+        assert_return(ppid, -EINVAL);
+
+        if (!(c->mask & SD_BUS_CREDS_PPID))
+                return -ENODATA;
+
+        *ppid = c->ppid;
+        return 0;
+}
+
 _public_ int sd_bus_creds_get_tid(sd_bus_creds *c, pid_t *tid) {
         assert_return(c, -EINVAL);
         assert_return(tid, -EINVAL);
@@ -663,32 +680,33 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
         if (!(mask & SD_BUS_CREDS_AUGMENT))
                 return 0;
 
-        missing = mask & ~c->mask;
-        if (missing == 0)
-                return 0;
-
         /* Try to retrieve PID from creds if it wasn't passed to us */
         if (pid <= 0 && (c->mask & SD_BUS_CREDS_PID))
                 pid = c->pid;
 
-        if (tid <= 0 && (c->mask & SD_BUS_CREDS_TID))
-                tid = c->pid;
-
         /* Without pid we cannot do much... */
         if (pid <= 0)
                 return 0;
 
-        if (pid > 0) {
-                c->pid = pid;
-                c->mask |= SD_BUS_CREDS_PID;
-        }
+        /* Try to retrieve TID from creds if it wasn't passed to us */
+        if (tid <= 0 && (c->mask & SD_BUS_CREDS_TID))
+                tid = c->tid;
+
+        /* Calculate what we shall and can add */
+        missing = mask & ~(c->mask|SD_BUS_CREDS_PID|SD_BUS_CREDS_TID|SD_BUS_CREDS_UNIQUE_NAME|SD_BUS_CREDS_WELL_KNOWN_NAMES|SD_BUS_CREDS_DESCRIPTION|SD_BUS_CREDS_AUGMENT);
+        if (missing == 0)
+                return 0;
+
+        c->pid = pid;
+        c->mask |= SD_BUS_CREDS_PID;
 
         if (tid > 0) {
                 c->tid = tid;
                 c->mask |= SD_BUS_CREDS_TID;
         }
 
-        if (missing & (SD_BUS_CREDS_UID | SD_BUS_CREDS_EUID | SD_BUS_CREDS_SUID | SD_BUS_CREDS_FSUID |
+        if (missing & (SD_BUS_CREDS_PPID |
+                       SD_BUS_CREDS_UID | SD_BUS_CREDS_EUID | SD_BUS_CREDS_SUID | SD_BUS_CREDS_FSUID |
                        SD_BUS_CREDS_GID | SD_BUS_CREDS_EGID | SD_BUS_CREDS_SGID | SD_BUS_CREDS_FSGID |
                        SD_BUS_CREDS_SUPPLEMENTARY_GIDS |
                        SD_BUS_CREDS_EFFECTIVE_CAPS | SD_BUS_CREDS_INHERITABLE_CAPS |
@@ -711,6 +729,23 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
                         FOREACH_LINE(line, f, return -errno) {
                                 truncate_nl(line);
 
+                                if (missing & SD_BUS_CREDS_PPID) {
+                                        p = startswith(line, "PPid:");
+                                        if (p) {
+                                                p += strspn(p, WHITESPACE);
+
+                                                /* Explicitly check for PPID 0 (which is the case for PID 1) */
+                                                if (!streq(p, "0")) {
+                                                        r = parse_pid(p, &c->ppid);
+                                                        if (r < 0)
+                                                                return r;
+
+                                                        c->mask |= SD_BUS_CREDS_PPID;
+                                                }
+                                                continue;
+                                        }
+                                }
+
                                 if (missing & (SD_BUS_CREDS_UID|SD_BUS_CREDS_EUID|SD_BUS_CREDS_SUID|SD_BUS_CREDS_FSUID)) {
                                         p = startswith(line, "Uid:");
                                         if (p) {
@@ -903,17 +938,22 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
 
         if (missing & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID)) {
 
-                r = cg_pid_get_path(NULL, pid, &c->cgroup);
-                if (r < 0) {
-                        if (r != -EPERM && r != -EACCES)
-                                return r;
-                } else {
+                if (!c->cgroup) {
+                        r = cg_pid_get_path(NULL, pid, &c->cgroup);
+                        if (r < 0) {
+                                if (r != -EPERM && r != -EACCES)
+                                        return r;
+                        }
+                }
+
+                if (!c->cgroup_root) {
                         r = cg_get_root_path(&c->cgroup_root);
                         if (r < 0)
                                 return r;
+                }
 
+                if (c->cgroup)
                         c->mask |= missing & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID);
-                }
         }
 
         if (missing & SD_BUS_CREDS_AUDIT_SESSION_ID) {
@@ -934,6 +974,8 @@ int bus_creds_add_more(sd_bus_creds *c, uint64_t mask, pid_t pid, pid_t tid) {
                         c->mask |= SD_BUS_CREDS_AUDIT_LOGIN_UID;
         }
 
+        c->augmented = missing & c->mask;
+
         return 0;
 }
 
@@ -968,6 +1010,11 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
                 n->mask |= SD_BUS_CREDS_TID;
         }
 
+        if (c->mask & mask & SD_BUS_CREDS_PPID) {
+                n->ppid = c->ppid;
+                n->mask |= SD_BUS_CREDS_PPID;
+        }
+
         if (c->mask & mask & SD_BUS_CREDS_UID) {
                 n->uid = c->uid;
                 n->mask |= SD_BUS_CREDS_UID;
@@ -1108,11 +1155,11 @@ int bus_creds_extend_by_pid(sd_bus_creds *c, uint64_t mask, sd_bus_creds **ret)
                 n->mask |= SD_BUS_CREDS_DESCRIPTION;
         }
 
+        n->augmented = c->augmented & n->mask;
+
         /* Get more data */
 
-        r = bus_creds_add_more(n, mask,
-                               c->mask & SD_BUS_CREDS_PID ? c->pid : 0,
-                               c->mask & SD_BUS_CREDS_TID ? c->tid : 0);
+        r = bus_creds_add_more(n, mask, 0, 0);
         if (r < 0)
                 return r;