bus: add new sd_bus_creds object to encapsulate process credentials

This way we can unify handling of credentials that are attached to
messages, or can be queried for bus name owners or connection peers.

This also adds the ability to extend incomplete credential information
with data from /proc,

Also, provide a convenience call that will automatically determine the
most appropriate credential object for an incoming message, by using the
the attached information if possible, the sending name information if
available and otherwise the peer's credentials.

1 files changed, 25 insertions, 19 deletions

diff --git a/src/libsystemd-bus/busctl.c b/src/libsystemd-bus/busctl.c
index 4204adb5bc..24db48a7e6 100644
--- a/src/libsystemd-bus/busctl.c
+++ b/src/libsystemd-bus/busctl.c
@@ -75,41 +75,47 @@ static int list_bus_names(sd_bus *bus, char **argv) {
                (int) max_i, "NAME", 10, "PID", 15, "PROCESS", 16, "USER", 20, "CONNECTION");
 
         STRV_FOREACH(i, l) {
+                _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
                 _cleanup_free_ char *owner = NULL;
                 sd_id128_t mid;
-                pid_t pid;
-                uid_t uid;
 
                 if (arg_no_unique && (*i)[0] == ':')
                         continue;
 
                 printf("%-*s", (int) max_i, *i);
 
-                r = sd_bus_get_owner_pid(bus, *i, &pid);
+                r = sd_bus_get_owner_creds(bus, *i, SD_BUS_CREDS_UID|SD_BUS_CREDS_PID|SD_BUS_CREDS_COMM, &creds);
                 if (r >= 0) {
-                        _cleanup_free_ char *comm = NULL;
+                        pid_t pid;
+                        uid_t uid;
 
-                        printf(" %10lu", (unsigned long) pid);
+                        r = sd_bus_creds_get_pid(creds, &pid);
+                        if (r >= 0) {
+                                const char *comm = NULL;
 
-                        get_process_comm(pid, &comm);
-                        printf(" %-15s", strna(comm));
-                } else
-                        printf("          - -              ");
+                                sd_bus_creds_get_comm(creds, &comm);
 
-                r = sd_bus_get_owner_uid(bus, *i, &uid);
-                if (r >= 0) {
-                        _cleanup_free_ char *u = NULL;
+                                printf(" %10lu %-15s", (unsigned long) pid, strna(comm));
+                        } else
+                                printf("          - -              ");
 
-                        u = uid_to_name(uid);
-                        if (!u)
-                                return log_oom();
+                        r = sd_bus_creds_get_uid(creds, &uid);
+                        if (r >= 0) {
+                                _cleanup_free_ char *u = NULL;
 
-                        if (strlen(u) > 16)
-                                u[16] = 0;
+                                u = uid_to_name(uid);
+                                if (!u)
+                                        return log_oom();
 
-                        printf(" %-16s", u);
+                                if (strlen(u) > 16)
+                                        u[16] = 0;
+
+                                printf(" %-16s", u);
+                        } else
+                                printf(" -               ");
                 } else
-                        printf(" -               ");
+                        printf("          - -               -               ");
+
 
                 r = sd_bus_get_owner(bus, *i, &owner);
                 if (r >= 0)