chiark / gitweb /
bus: allow omitting quotes for values in match strings
[elogind.git] / src / libsystemd-bus / bus-match.c
index 750acfe6d5386dcfad5ff31a6c9ce494baf5964d..ffc97562fd8e286d12db6f6deeabf82f3c440f57 100644 (file)
@@ -22,6 +22,9 @@
 #include "bus-internal.h"
 #include "bus-message.h"
 #include "bus-match.h"
+#include "bus-error.h"
+#include "bus-util.h"
+#include "strv.h"
 
 /* Example:
  *
@@ -60,7 +63,7 @@
  */
 
 static inline bool BUS_MATCH_IS_COMPARE(enum bus_match_node_type t) {
-        return t >= BUS_MATCH_MESSAGE_TYPE && t <= BUS_MATCH_ARG_NAMESPACE_LAST;
+        return t >= BUS_MATCH_SENDER && t <= BUS_MATCH_ARG_NAMESPACE_LAST;
 }
 
 static inline bool BUS_MATCH_CAN_HASH(enum bus_match_node_type t) {
@@ -127,7 +130,8 @@ static bool value_node_test(
                 struct bus_match_node *node,
                 enum bus_match_node_type parent_type,
                 uint8_t value_u8,
-                const char *value_str) {
+                const char *value_str,
+                sd_bus_message *m) {
 
         assert(node);
         assert(node->type == BUS_MATCH_VALUE);
@@ -141,6 +145,33 @@ static bool value_node_test(
                 return node->value.u8 == value_u8;
 
         case BUS_MATCH_SENDER:
+                if (streq_ptr(node->value.str, value_str))
+                        return true;
+
+                if (m->creds.mask & SD_BUS_CREDS_WELL_KNOWN_NAMES) {
+                        char **i;
+
+                        /* on kdbus we have the well known names list
+                         * in the credentials, let's make use of that
+                         * for an accurate match */
+
+                        STRV_FOREACH(i, m->creds.well_known_names)
+                                if (streq_ptr(node->value.str, *i))
+                                        return true;
+
+                } else {
+
+                        /* If we don't have kdbus, we don't know the
+                         * well-known names of the senders. In that,
+                         * let's just hope that dbus-daemon doesn't
+                         * send us stuff we didn't want. */
+
+                        if (node->value.str[0] != ':' && value_str && value_str[0] == ':')
+                                return true;
+                }
+
+                return false;
+
         case BUS_MATCH_DESTINATION:
         case BUS_MATCH_INTERFACE:
         case BUS_MATCH_MEMBER:
@@ -256,7 +287,10 @@ int bus_match_run(
 
                 /* Run the callback. And then invoke siblings. */
                 if (node->leaf.callback) {
-                        r = node->leaf.callback(bus, m, node->leaf.userdata);
+                        _cleanup_bus_error_free_ sd_bus_error error_buffer = SD_BUS_ERROR_NULL;
+
+                        r = node->leaf.callback(bus, m, node->leaf.userdata, &error_buffer);
+                        r = bus_maybe_reply_error(m, r, &error_buffer);
                         if (r != 0)
                                 return r;
                 }
@@ -328,7 +362,7 @@ int bus_match_run(
                 /* No hash table, so let's iterate manually... */
 
                 for (c = node->child; c; c = c->next) {
-                        if (!value_node_test(c, node->type, test_u8, test_str))
+                        if (!value_node_test(c, node->type, test_u8, test_str, m))
                                 continue;
 
                         r = bus_match_run(bus, c, m);
@@ -555,22 +589,22 @@ static int bus_match_find_leaf(
 enum bus_match_node_type bus_match_node_type_from_string(const char *k, size_t n) {
         assert(k);
 
-        if (n == 4 && hasprefix(k, "type"))
+        if (n == 4 && startswith(k, "type"))
                 return BUS_MATCH_MESSAGE_TYPE;
-        if (n == 6 && hasprefix(k, "sender"))
+        if (n == 6 && startswith(k, "sender"))
                 return BUS_MATCH_SENDER;
-        if (n == 11 && hasprefix(k, "destination"))
+        if (n == 11 && startswith(k, "destination"))
                 return BUS_MATCH_DESTINATION;
-        if (n == 9 && hasprefix(k, "interface"))
+        if (n == 9 && startswith(k, "interface"))
                 return BUS_MATCH_INTERFACE;
-        if (n == 6 && hasprefix(k, "member"))
+        if (n == 6 && startswith(k, "member"))
                 return BUS_MATCH_MEMBER;
-        if (n == 4 && hasprefix(k, "path"))
+        if (n == 4 && startswith(k, "path"))
                 return BUS_MATCH_PATH;
-        if (n == 14 && hasprefix(k, "path_namespace"))
+        if (n == 14 && startswith(k, "path_namespace"))
                 return BUS_MATCH_PATH_NAMESPACE;
 
-        if (n == 4 && hasprefix(k, "arg")) {
+        if (n == 4 && startswith(k, "arg")) {
                 int j;
 
                 j = undecchar(k[3]);
@@ -580,7 +614,7 @@ enum bus_match_node_type bus_match_node_type_from_string(const char *k, size_t n
                 return BUS_MATCH_ARG + j;
         }
 
-        if (n == 5 && hasprefix(k, "arg")) {
+        if (n == 5 && startswith(k, "arg")) {
                 int a, b;
                 enum bus_match_node_type t;
 
@@ -596,7 +630,7 @@ enum bus_match_node_type bus_match_node_type_from_string(const char *k, size_t n
                 return t;
         }
 
-        if (n == 8 && hasprefix(k, "arg") && hasprefix(k + 4, "path")) {
+        if (n == 8 && startswith(k, "arg") && startswith(k + 4, "path")) {
                 int j;
 
                 j = undecchar(k[3]);
@@ -606,7 +640,7 @@ enum bus_match_node_type bus_match_node_type_from_string(const char *k, size_t n
                 return BUS_MATCH_ARG_PATH + j;
         }
 
-        if (n == 9 && hasprefix(k, "arg") && hasprefix(k + 5, "path")) {
+        if (n == 9 && startswith(k, "arg") && startswith(k + 5, "path")) {
                 enum bus_match_node_type t;
                 int a, b;
 
@@ -622,7 +656,7 @@ enum bus_match_node_type bus_match_node_type_from_string(const char *k, size_t n
                 return t;
         }
 
-        if (n == 13 && hasprefix(k, "arg") && hasprefix(k + 4, "namespace")) {
+        if (n == 13 && startswith(k, "arg") && startswith(k + 4, "namespace")) {
                 int j;
 
                 j = undecchar(k[3]);
@@ -632,7 +666,7 @@ enum bus_match_node_type bus_match_node_type_from_string(const char *k, size_t n
                 return BUS_MATCH_ARG_NAMESPACE + j;
         }
 
-        if (n == 14 && hasprefix(k, "arg") && hasprefix(k + 5, "namespace")) {
+        if (n == 14 && startswith(k, "arg") && startswith(k + 5, "namespace")) {
                 enum bus_match_node_type t;
                 int a, b;
 
@@ -692,25 +726,31 @@ int bus_match_parse(
                 enum bus_match_node_type t;
                 unsigned j = 0;
                 size_t value_allocated = 0;
-                bool escaped = false;
+                bool escaped = false, quoted;
                 uint8_t u;
 
                 eq = strchr(p, '=');
                 if (!eq)
                         return -EINVAL;
 
-                if (eq[1] != '\'')
-                        return -EINVAL;
-
                 t = bus_match_node_type_from_string(p, eq - p);
                 if (t < 0)
                         return -EINVAL;
 
-                for (q = eq + 2;; q++) {
+                quoted = eq[1] == '\'';
+
+                for (q = eq + 1 + quoted;; q++) {
 
                         if (*q == 0) {
-                                r = -EINVAL;
-                                goto fail;
+
+                                if (quoted) {
+                                        r = -EINVAL;
+                                        goto fail;
+                                } else {
+                                        if (value)
+                                                value[j] = 0;
+                                        break;
+                                }
                         }
 
                         if (!escaped) {
@@ -718,10 +758,20 @@ int bus_match_parse(
                                         escaped = true;
                                         continue;
                                 }
-                                if (*q == '\'') {
-                                        if (value)
-                                                value[j] = 0;
-                                        break;
+
+                                if (quoted) {
+                                        if (*q == '\'') {
+                                                if (value)
+                                                        value[j] = 0;
+                                                break;
+                                        }
+                                } else {
+                                        if (*q == ',') {
+                                                if (value)
+                                                        value[j] = 0;
+
+                                                break;
+                                        }
                                 }
                         }
 
@@ -734,6 +784,14 @@ int bus_match_parse(
                         escaped = false;
                 }
 
+                if (!value) {
+                        value = strdup("");
+                        if (!value) {
+                                r = -ENOMEM;
+                                goto fail;
+                        }
+                }
+
                 if (t == BUS_MATCH_MESSAGE_TYPE) {
                         r = bus_message_type_from_string(value, &u);
                         if (r < 0)
@@ -759,16 +817,16 @@ int bus_match_parse(
                 if (q[1] == 0)
                         break;
 
-                if (q[1] != ',') {
+                if (q[quoted] != ',') {
                         r = -EINVAL;
                         goto fail;
                 }
 
-                p = q + 2;
+                p = q + 1 + quoted;
         }
 
         /* Order the whole thing, so that we always generate the same tree */
-        qsort(components, n_components, sizeof(struct bus_match_component), match_component_compare);
+        qsort_safe(components, n_components, sizeof(struct bus_match_component), match_component_compare);
 
         /* Check for duplicates */
         for (i = 0; i+1 < n_components; i++)
@@ -787,6 +845,46 @@ fail:
         return r;
 }
 
+char *bus_match_to_string(struct bus_match_component *components, unsigned n_components) {
+        _cleanup_free_ FILE *f = NULL;
+        char *buffer = NULL;
+        size_t size = 0;
+        unsigned i;
+
+        if (n_components <= 0)
+                return strdup("");
+
+        assert(components);
+
+        f = open_memstream(&buffer, &size);
+        if (!f)
+                return NULL;
+
+        for (i = 0; i < n_components; i++) {
+                char buf[32];
+
+                if (i != 0)
+                        fputc(',', f);
+
+                fputs(bus_match_node_type_to_string(components[i].type, buf, sizeof(buf)), f);
+                fputc('=', f);
+                fputc('\'', f);
+
+                if (components[i].type == BUS_MATCH_MESSAGE_TYPE)
+                        fputs(bus_message_type_to_string(components[i].value_u8), f);
+                else
+                        fputs(components[i].value_str, f);
+
+                fputc('\'', f);
+        }
+
+        fflush(f);
+        if (ferror(f))
+                return NULL;
+
+        return buffer;
+}
+
 int bus_match_add(
                 struct bus_match_node *root,
                 struct bus_match_component *components,