X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fcgroup-util.c;h=b286243c3629cb165ed3c8c353f50b5387e80f8e;hb=d896ac2d2fbce41a0b11a0618a685adeaf18b8fe;hp=2e2984a35c372451de58ba1150b56d0b9b4a7912;hpb=7e39f6b1d98095ca2080a229048e14f10a6e1c5b;p=elogind.git

diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c
index 2e2984a35..b286243c3 100644
--- a/src/shared/cgroup-util.c
+++ b/src/shared/cgroup-util.c
@@ -33,10 +33,13 @@
 #include "set.h"
 #include "macro.h"
 #include "util.h"
+#include "formats-util.h"
 #include "path-util.h"
+#include "unit-name.h"
 #include "fileio.h"
 #include "special.h"
 #include "mkdir.h"
+#include "login-shared.h"
 
 int cg_enumerate_processes(const char *controller, const char *path, FILE **_f) {
         _cleanup_free_ char *fs = NULL;
@@ -437,9 +440,7 @@ static const char *normalize_controller(const char *controller) {
 
         assert(controller);
 
-        if (streq(controller, SYSTEMD_CGROUP_CONTROLLER))
-                return "elogind";
-        else if (startswith(controller, "name="))
+        if (startswith(controller, "name="))
                 return controller + 5;
         else
                 return controller;
@@ -479,13 +480,13 @@ int cg_get_path(const char *controller, const char *path, const char *suffix, ch
 
         assert(fs);
 
-        if (controller && !cg_controller_is_valid(controller, true))
+        if (controller && !cg_controller_is_valid(controller))
                 return -EINVAL;
 
         if (_unlikely_(!good)) {
                 int r;
 
-                r = path_is_mount_point("/sys/fs/cgroup", false);
+                r = path_is_mount_point("/sys/fs/cgroup", 0);
                 if (r < 0)
                         return r;
                 if (r == 0)
@@ -522,7 +523,7 @@ int cg_get_path_and_check(const char *controller, const char *path, const char *
 
         assert(fs);
 
-        if (!cg_controller_is_valid(controller, true))
+        if (!cg_controller_is_valid(controller))
                 return -EINVAL;
 
         /* Normalize the controller syntax */
@@ -738,7 +739,7 @@ int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
         assert(pid >= 0);
 
         if (controller) {
-                if (!cg_controller_is_valid(controller, true))
+                if (!cg_controller_is_valid(controller))
                         return -EINVAL;
 
                 controller = normalize_controller(controller);
@@ -967,7 +968,7 @@ int cg_split_spec(const char *spec, char **controller, char **path) {
 
         e = strchr(spec, ':');
         if (!e) {
-                if (!cg_controller_is_valid(spec, true))
+                if (!cg_controller_is_valid(spec))
                         return -EINVAL;
 
                 if (controller) {
@@ -990,7 +991,7 @@ int cg_split_spec(const char *spec, char **controller, char **path) {
         t = strdup(normalize_controller(v));
         if (!t)
                 return -ENOMEM;
-        if (!cg_controller_is_valid(t, true)) {
+        if (!cg_controller_is_valid(t)) {
                 free(t);
                 return -EINVAL;
         }
@@ -1059,9 +1060,21 @@ int cg_mangle_path(const char *path, char **result) {
 }
 
 int cg_get_root_path(char **path) {
+        char *p, *e;
+        int r;
+
         assert(path);
 
-        return cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 1, path);
+        r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 1, &p);
+        if (r < 0)
+                return r;
+
+        e = endswith(p, "/" SPECIAL_SYSTEM_SLICE);
+        if (e)
+                *e = 0;
+
+        *path = p;
+        return 0;
 }
 
 int cg_shift_path(const char *cgroup, const char *root, const char **shifted) {
@@ -1124,34 +1137,287 @@ int cg_pid_get_path_shifted(pid_t pid, const char *root, char **cgroup) {
         return 0;
 }
 
-int cg_path_get_session(const char *path, char **session) {
-        const char *e, *n, *s;
+int cg_path_decode_unit(const char *cgroup, char **unit){
+        char *c, *s;
+        size_t n;
+
+        assert(cgroup);
+        assert(unit);
+
+        n = strcspn(cgroup, "/");
+        if (n < 3)
+                return -ENXIO;
+
+        c = strndupa(cgroup, n);
+        c = cg_unescape(c);
+
+        if (!unit_name_is_valid(c, UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE))
+                return -ENXIO;
+
+        s = strdup(c);
+        if (!s)
+                return -ENOMEM;
+
+        *unit = s;
+        return 0;
+}
+
+static bool valid_slice_name(const char *p, size_t n) {
+
+        if (!p)
+                return false;
+
+        if (n < strlen("x.slice"))
+                return false;
+
+        if (memcmp(p + n - 6, ".slice", 6) == 0) {
+                char buf[n+1], *c;
+
+                memcpy(buf, p, n);
+                buf[n] = 0;
+
+                c = cg_unescape(buf);
+
+                return unit_name_is_valid(c, UNIT_NAME_PLAIN);
+        }
+
+        return false;
+}
+
+static const char *skip_slices(const char *p) {
+        assert(p);
+
+        /* Skips over all slice assignments */
+
+        for (;;) {
+                size_t n;
+
+                p += strspn(p, "/");
+
+                n = strcspn(p, "/");
+                if (!valid_slice_name(p, n))
+                        return p;
+
+                p += n;
+        }
+}
+
+int cg_path_get_unit(const char *path, char **ret) {
+        const char *e;
+        char *unit;
+        int r;
+
+        assert(path);
+        assert(ret);
+
+        e = skip_slices(path);
+
+        r = cg_path_decode_unit(e, &unit);
+        if (r < 0)
+                return r;
+
+        /* We skipped over the slices, don't accept any now */
+        if (endswith(unit, ".slice")) {
+                free(unit);
+                return -ENXIO;
+        }
+
+        *ret = unit;
+        return 0;
+}
+
+int cg_pid_get_unit(pid_t pid, char **unit) {
+        _cleanup_free_ char *cgroup = NULL;
+        int r;
 
-        /* Elogind uses a flat hierarchy, just "/SESSION".  The only
-           wrinkle is that SESSION might be escaped.  */
+        assert(unit);
+
+        r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+        if (r < 0)
+                return r;
+
+        return cg_path_get_unit(cgroup, unit);
+}
+
+/**
+ * Skip session-*.scope, but require it to be there.
+ */
+static const char *skip_session(const char *p) {
+        size_t n;
+
+        if (isempty(p))
+                return NULL;
+
+        p += strspn(p, "/");
+
+        n = strcspn(p, "/");
+        if (n < strlen("session-x.scope"))
+                return NULL;
+
+        if (memcmp(p, "session-", 8) == 0 && memcmp(p + n - 6, ".scope", 6) == 0) {
+                char buf[n - 8 - 6 + 1];
+
+                memcpy(buf, p + 8, n - 8 - 6);
+                buf[n - 8 - 6] = 0;
+
+                /* Note that session scopes never need unescaping,
+                 * since they cannot conflict with the kernel's own
+                 * names, hence we don't need to call cg_unescape()
+                 * here. */
+
+                if (!session_id_valid(buf))
+                        return false;
+
+                p += n;
+                p += strspn(p, "/");
+                return p;
+        }
+
+        return NULL;
+}
+
+/**
+ * Skip user@*.service, but require it to be there.
+ */
+static const char *skip_user_manager(const char *p) {
+        size_t n;
+
+        if (isempty(p))
+                return NULL;
+
+        p += strspn(p, "/");
+
+        n = strcspn(p, "/");
+        if (n < strlen("user@x.service"))
+                return NULL;
+
+        if (memcmp(p, "user@", 5) == 0 && memcmp(p + n - 8, ".service", 8) == 0) {
+                char buf[n - 5 - 8 + 1];
+
+                memcpy(buf, p + 5, n - 5 - 8);
+                buf[n - 5 - 8] = 0;
+
+                /* Note that user manager services never need unescaping,
+                 * since they cannot conflict with the kernel's own
+                 * names, hence we don't need to call cg_unescape()
+                 * here. */
+
+                if (parse_uid(buf, NULL) < 0)
+                        return NULL;
+
+                p += n;
+                p += strspn(p, "/");
+
+                return p;
+        }
+
+        return NULL;
+}
+
+static const char *skip_user_prefix(const char *path) {
+        const char *e, *t;
 
         assert(path);
-        assert(path[0] == '/');
 
-        e = path + 1;
-        n = strchrnul(e, '/');
-        if (e == n)
-                return -ENOENT;
+        /* Skip slices, if there are any */
+        e = skip_slices(path);
+
+        /* Skip the user manager, if it's in the path now... */
+        t = skip_user_manager(e);
+        if (t)
+                return t;
+
+        /* Alternatively skip the user session if it is in the path... */
+        return skip_session(e);
+}
+
+int cg_path_get_user_unit(const char *path, char **ret) {
+        const char *t;
+
+        assert(path);
+        assert(ret);
+
+        t = skip_user_prefix(path);
+        if (!t)
+                return -ENXIO;
+
+        /* And from here on it looks pretty much the same as for a
+         * system unit, hence let's use the same parser from here
+         * on. */
+        return cg_path_get_unit(t, ret);
+}
+
+int cg_pid_get_user_unit(pid_t pid, char **unit) {
+        _cleanup_free_ char *cgroup = NULL;
+        int r;
+
+        assert(unit);
+
+        r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+        if (r < 0)
+                return r;
 
-        s = strndupa(e, n - e);
-        s = cg_unescape(s);
+        return cg_path_get_user_unit(cgroup, unit);
+}
 
-        if (!s[0])
-                return -ENOENT;
+int cg_path_get_machine_name(const char *path, char **machine) {
+        _cleanup_free_ char *u = NULL, *sl = NULL;
+        int r;
+
+        r = cg_path_get_unit(path, &u);
+        if (r < 0)
+                return r;
+
+        sl = strjoin("/run/systemd/machines/unit:", u, NULL);
+        if (!sl)
+                return -ENOMEM;
+
+        return readlink_malloc(sl, machine);
+}
+
+int cg_pid_get_machine_name(pid_t pid, char **machine) {
+        _cleanup_free_ char *cgroup = NULL;
+        int r;
+
+        assert(machine);
+
+        r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+        if (r < 0)
+                return r;
+
+        return cg_path_get_machine_name(cgroup, machine);
+}
+
+int cg_path_get_session(const char *path, char **session) {
+        _cleanup_free_ char *unit = NULL;
+        char *start, *end;
+        int r;
+
+        assert(path);
+
+        r = cg_path_get_unit(path, &unit);
+        if (r < 0)
+                return r;
+
+        start = startswith(unit, "session-");
+        if (!start)
+                return -ENXIO;
+        end = endswith(start, ".scope");
+        if (!end)
+                return -ENXIO;
+
+        *end = 0;
+        if (!session_id_valid(start))
+                return -ENXIO;
 
         if (session) {
-                char *r;
+                char *rr;
 
-                r = strdup(s);
-                if (!r)
+                rr = strdup(start);
+                if (!rr)
                         return -ENOMEM;
 
-                *session = r;
+                *session = rr;
         }
 
         return 0;
@@ -1168,6 +1434,118 @@ int cg_pid_get_session(pid_t pid, char **session) {
         return cg_path_get_session(cgroup, session);
 }
 
+int cg_path_get_owner_uid(const char *path, uid_t *uid) {
+        _cleanup_free_ char *slice = NULL;
+        char *start, *end;
+        int r;
+
+        assert(path);
+
+        r = cg_path_get_slice(path, &slice);
+        if (r < 0)
+                return r;
+
+        start = startswith(slice, "user-");
+        if (!start)
+                return -ENXIO;
+        end = endswith(start, ".slice");
+        if (!end)
+                return -ENXIO;
+
+        *end = 0;
+        if (parse_uid(start, uid) < 0)
+                return -ENXIO;
+
+        return 0;
+}
+
+int cg_pid_get_owner_uid(pid_t pid, uid_t *uid) {
+        _cleanup_free_ char *cgroup = NULL;
+        int r;
+
+        r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+        if (r < 0)
+                return r;
+
+        return cg_path_get_owner_uid(cgroup, uid);
+}
+
+int cg_path_get_slice(const char *p, char **slice) {
+        const char *e = NULL;
+
+        assert(p);
+        assert(slice);
+
+        /* Finds the right-most slice unit from the beginning, but
+         * stops before we come to the first non-slice unit. */
+
+        for (;;) {
+                size_t n;
+
+                p += strspn(p, "/");
+
+                n = strcspn(p, "/");
+                if (!valid_slice_name(p, n)) {
+
+                        if (!e) {
+                                char *s;
+
+                                s = strdup("-.slice");
+                                if (!s)
+                                        return -ENOMEM;
+
+                                *slice = s;
+                                return 0;
+                        }
+
+                        return cg_path_decode_unit(e, slice);
+                }
+
+                e = p;
+                p += n;
+        }
+}
+
+int cg_pid_get_slice(pid_t pid, char **slice) {
+        _cleanup_free_ char *cgroup = NULL;
+        int r;
+
+        assert(slice);
+
+        r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+        if (r < 0)
+                return r;
+
+        return cg_path_get_slice(cgroup, slice);
+}
+
+int cg_path_get_user_slice(const char *p, char **slice) {
+        const char *t;
+        assert(p);
+        assert(slice);
+
+        t = skip_user_prefix(p);
+        if (!t)
+                return -ENXIO;
+
+        /* And now it looks pretty much the same as for a system
+         * slice, so let's just use the same parser from here on. */
+        return cg_path_get_slice(t, slice);
+}
+
+int cg_pid_get_user_slice(pid_t pid, char **slice) {
+        _cleanup_free_ char *cgroup = NULL;
+        int r;
+
+        assert(slice);
+
+        r = cg_pid_get_path_shifted(pid, NULL, &cgroup);
+        if (r < 0)
+                return r;
+
+        return cg_path_get_user_slice(cgroup, slice);
+}
+
 char *cg_escape(const char *p) {
         bool need_prefix = false;
 
@@ -1229,17 +1607,15 @@ char *cg_unescape(const char *p) {
         DIGITS LETTERS                          \
         "_"
 
-bool cg_controller_is_valid(const char *p, bool allow_named) {
+bool cg_controller_is_valid(const char *p) {
         const char *t, *s;
 
         if (!p)
                 return false;
 
-        if (allow_named) {
-                s = startswith(p, "name=");
-                if (s)
-                        p = s;
-        }
+        s = startswith(p, "name=");
+        if (s)
+                p = s;
 
         if (*p == 0 || *p == '_')
                 return false;
@@ -1254,6 +1630,69 @@ bool cg_controller_is_valid(const char *p, bool allow_named) {
         return true;
 }
 
+int cg_slice_to_path(const char *unit, char **ret) {
+        _cleanup_free_ char *p = NULL, *s = NULL, *e = NULL;
+        const char *dash;
+        int r;
+
+        assert(unit);
+        assert(ret);
+
+        if (streq(unit, "-.slice")) {
+                char *x;
+
+                x = strdup("");
+                if (!x)
+                        return -ENOMEM;
+                *ret = x;
+                return 0;
+        }
+
+        if (!unit_name_is_valid(unit, UNIT_NAME_PLAIN))
+                return -EINVAL;
+
+        if (!endswith(unit, ".slice"))
+                return -EINVAL;
+
+        r = unit_name_to_prefix(unit, &p);
+        if (r < 0)
+                return r;
+
+        dash = strchr(p, '-');
+        while (dash) {
+                _cleanup_free_ char *escaped = NULL;
+                char n[dash - p + sizeof(".slice")];
+
+                if (isempty(dash + 1))
+                        return -EINVAL;
+
+                strcpy(stpncpy(n, p, dash - p), ".slice");
+                if (!unit_name_is_valid(n, UNIT_NAME_PLAIN))
+                        return -EINVAL;
+
+                escaped = cg_escape(n);
+                if (!escaped)
+                        return -ENOMEM;
+
+                if (!strextend(&s, escaped, "/", NULL))
+                        return -ENOMEM;
+
+                dash = strchr(dash+1, '-');
+        }
+
+        e = cg_escape(unit);
+        if (!e)
+                return -ENOMEM;
+
+        if (!strextend(&s, e, NULL))
+                return -ENOMEM;
+
+        *ret = s;
+        s = NULL;
+
+        return 0;
+}
+
 int cg_set_attribute(const char *controller, const char *path, const char *attribute, const char *value) {
         _cleanup_free_ char *p = NULL;
         int r;