chiark / gitweb /
bus: validate the hello response properly
[elogind.git] / src / libsystemd-bus / sd-bus.c
index 3f23da6ff538bfd2e95f9e09e5a804c0f2b52d6c..4bfbd4c651cdf694a997ede987a7f4da57038c7e 100644 (file)
 #include "bus-message.h"
 #include "bus-type.h"
 
-#define WQUEUE_MAX 128
+static int ensure_running(sd_bus *bus);
+static int bus_poll(sd_bus *bus, bool need_more, uint64_t timeout_usec);
 
 static void bus_free(sd_bus *b) {
         struct filter_callback *f;
+        unsigned i;
 
         assert(b);
 
@@ -46,11 +48,20 @@ static void bus_free(sd_bus *b) {
                 close_nointr_nofail(b->fd);
 
         free(b->rbuffer);
+        free(b->unique_name);
+        free(b->auth_uid);
+        free(b->address);
+
+        for (i = 0; i < b->rqueue_size; i++)
+                sd_bus_message_unref(b->rqueue[i]);
         free(b->rqueue);
+
+        for (i = 0; i < b->wqueue_size; i++)
+                sd_bus_message_unref(b->wqueue[i]);
         free(b->wqueue);
-        free(b->unique_name);
 
         hashmap_free_free(b->reply_callbacks);
+        prioq_free(b->reply_callbacks_prioq);
 
         while ((f = b->filter_callbacks)) {
                 LIST_REMOVE(struct filter_callback, callbacks, b->filter_callbacks, f);
@@ -82,23 +93,30 @@ static sd_bus* bus_new(void) {
         return r;
 };
 
-static int hello_callback(sd_bus *bus, sd_bus_message *reply, void *userdata) {
+static int hello_callback(sd_bus *bus, int error, sd_bus_message *reply, void *userdata) {
         const char *s;
         int r;
 
         assert(bus);
-        assert(reply);
 
-        bus->state = BUS_RUNNING;
+        if (error != 0)
+                return -error;
+
+        assert(reply);
 
         r = sd_bus_message_read(reply, "s", &s);
         if (r < 0)
                 return r;
 
+        if (!service_name_is_valid(s) || s[0] != ':')
+                return -EBADMSG;
+
         bus->unique_name = strdup(s);
         if (!bus->unique_name)
                 return -ENOMEM;
 
+        bus->state = BUS_RUNNING;
+
         return 1;
 }
 
@@ -118,29 +136,24 @@ static int bus_send_hello(sd_bus *bus) {
         if (r < 0)
                 return r;
 
-        r = sd_bus_send_with_reply(bus, m, hello_callback, NULL, (uint64_t) -1, NULL);
+        r = sd_bus_send_with_reply(bus, m, hello_callback, NULL, 0, NULL);
         if (r < 0)
                 return r;
 
-        return 0;
+        bus->sent_hello = true;
+        return r;
 }
 
 static int bus_start_running(sd_bus *bus) {
-        int r;
-
         assert(bus);
 
-        if (bus->send_hello) {
+        if (bus->sent_hello) {
                 bus->state = BUS_HELLO;
-
-                r = bus_send_hello(bus);
-                if (r < 0)
-                        return r;
+                return 1;
         }
 
         bus->state = BUS_RUNNING;
-
-        return 0;
+        return 1;
 }
 
 static int parse_address_key(const char **p, const char *key, char **value) {
@@ -154,7 +167,7 @@ static int parse_address_key(const char **p, const char *key, char **value) {
         assert(value);
 
         l = strlen(key);
-        if (!strncmp(*p, key, l) != 0)
+        if (strncmp(*p, key, l) != 0)
                 return 0;
 
         if ((*p)[l] != '=')
@@ -164,7 +177,7 @@ static int parse_address_key(const char **p, const char *key, char **value) {
                 return -EINVAL;
 
         a = *p + l + 1;
-        while (*a != ';' && *a != 0) {
+        while (*a != ',' && *a != 0) {
                 char c, *t;
 
                 if (*a == '%') {
@@ -182,12 +195,14 @@ static int parse_address_key(const char **p, const char *key, char **value) {
                                 return y;
                         }
 
-                        a += 3;
                         c = (char) ((x << 4) | y);
-                } else
+                        a += 3;
+                } else {
                         c = *a;
+                        a++;
+                }
 
-                t = realloc(r, n + 1);
+                t = realloc(r, n + 2);
                 if (!t) {
                         free(r);
                         return -ENOMEM;
@@ -197,6 +212,16 @@ static int parse_address_key(const char **p, const char *key, char **value) {
                 r[n++] = c;
         }
 
+        if (!r) {
+                r = strdup("");
+                if (!r)
+                        return -ENOMEM;
+        } else
+                r[n] = 0;
+
+        if (*a == ',')
+                a++;
+
         *p = a;
         *value = r;
         return 1;
@@ -206,7 +231,10 @@ static void skip_address_key(const char **p) {
         assert(p);
         assert(*p);
 
-        *p += strcspn(*p, ";");
+        *p += strcspn(*p, ",");
+
+        if (**p == ',')
+                (*p) ++;
 }
 
 static int bus_parse_next_address(sd_bus *b) {
@@ -231,7 +259,7 @@ static int bus_parse_next_address(sd_bus *b) {
                 _cleanup_free_ char *path = NULL, *abstract = NULL;
 
                 p = a + 5;
-                while (*p != 0 && *p != ';') {
+                while (*p != 0) {
                         r = parse_address_key(&p, "guid", &guid);
                         if (r < 0)
                                 return r;
@@ -272,13 +300,13 @@ static int bus_parse_next_address(sd_bus *b) {
                 } else if (abstract) {
                         size_t l;
 
-                        l = strlen(path);
+                        l = strlen(abstract);
                         if (l > sizeof(b->sockaddr.un.sun_path) - 1)
                                 return -E2BIG;
 
                         b->sockaddr.un.sun_family = AF_UNIX;
                         b->sockaddr.un.sun_path[0] = 0;
-                        strncpy(b->sockaddr.un.sun_path+1, path, sizeof(b->sockaddr.un.sun_path)-1);
+                        strncpy(b->sockaddr.un.sun_path+1, abstract, sizeof(b->sockaddr.un.sun_path)-1);
                         b->sockaddr_size = offsetof(struct sockaddr_un, sun_path) + 1 + l;
                 }
 
@@ -287,7 +315,7 @@ static int bus_parse_next_address(sd_bus *b) {
                 struct addrinfo hints, *result;
 
                 p = a + 4;
-                while (*p != 0 && *p != ';') {
+                while (*p != 0) {
                         r = parse_address_key(&p, "guid", &guid);
                         if (r < 0)
                                 return r;
@@ -383,6 +411,9 @@ static int bus_write_auth(sd_bus *b) {
         if (b->auth_index >= ELEMENTSOF(b->auth_iovec))
                 return 0;
 
+        if (b->auth_timeout == 0)
+                b->auth_timeout = now(CLOCK_MONOTONIC) + BUS_DEFAULT_TIMEOUT;
+
         zero(mh);
         mh.msg_iov = b->auth_iovec + b->auth_index;
         mh.msg_iovlen = ELEMENTSOF(b->auth_iovec) - b->auth_index;
@@ -409,7 +440,7 @@ static int bus_auth_verify(sd_bus *b) {
         if (!e)
                 return 0;
 
-        f = memmem(e, b->rbuffer_size - (e - (char*) b->rbuffer), "\r\n", 2);
+        f = memmem(e + 2, b->rbuffer_size - (e - (char*) b->rbuffer) - 2, "\r\n", 2);
         if (!f)
                 return 0;
 
@@ -423,7 +454,7 @@ static int bus_auth_verify(sd_bus *b) {
                 int x, y;
 
                 x = unhexchar(((char*) b->rbuffer)[3 + i]);
-                y = unhexchar(((char*) b->rbuffer)[3 + i + 2]);
+                y = unhexchar(((char*) b->rbuffer)[3 + i + 1]);
 
                 if (x < 0 || y < 0)
                         return -EINVAL;
@@ -441,10 +472,8 @@ static int bus_auth_verify(sd_bus *b) {
                 (f - e == sizeof("\r\nAGREE_UNIX_FD") - 1) &&
                 memcmp(e + 2, "AGREE_UNIX_FD", sizeof("AGREE_UNIX_FD") - 1) == 0;
 
-        if (f + 2 > (char*) b->rbuffer + b->rbuffer_size) {
-                b->rbuffer_size -= (f - (char*) b->rbuffer);
-                memmove(b->rbuffer, f + 2, b->rbuffer_size);
-        }
+        b->rbuffer_size -= (f + 2 - (char*) b->rbuffer);
+        memmove(b->rbuffer, f + 2, b->rbuffer_size);
 
         r = bus_start_running(b);
         if (r < 0)
@@ -459,6 +488,7 @@ static int bus_read_auth(sd_bus *b) {
         size_t n;
         ssize_t k;
         int r;
+        void *p;
 
         assert(b);
 
@@ -468,6 +498,18 @@ static int bus_read_auth(sd_bus *b) {
 
         n = MAX(3 + 32 + 2 + sizeof("AGREE_UNIX_FD") - 1 + 2, b->rbuffer_size * 2);
 
+        if (n > BUS_AUTH_SIZE_MAX)
+                n = BUS_AUTH_SIZE_MAX;
+
+        if (b->rbuffer_size >= n)
+                return -ENOBUFS;
+
+        p = realloc(b->rbuffer, n);
+        if (!p)
+                return -ENOMEM;
+
+        b->rbuffer = p;
+
         zero(iov);
         iov.iov_base = (uint8_t*) b->rbuffer + b->rbuffer_size;
         iov.iov_len = n - b->rbuffer_size;
@@ -486,11 +528,11 @@ static int bus_read_auth(sd_bus *b) {
         if (r != 0)
                 return r;
 
-        return 0;
+        return 1;
 }
 
 static int bus_start_auth(sd_bus *b) {
-        static const char auth_prefix[] = "\0AUTH_EXTERNAL ";
+        static const char auth_prefix[] = "\0AUTH EXTERNAL ";
         static const char auth_suffix[] = "\r\nNEGOTIATE_UNIX_FD\r\nBEGIN\r\n";
 
         char text[20 + 1]; /* enough space for a 64bit integer plus NUL */
@@ -531,12 +573,12 @@ static int bus_start_connect(sd_bus *b) {
                         if (r < 0)
                                 return r;
                         if (r == 0)
-                                return b->last_connect_error ? b->last_connect_error : -ECONNREFUSED;
+                                return b->last_connect_error ? -b->last_connect_error : -ECONNREFUSED;
                 }
 
                 b->fd = socket(b->sockaddr.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
                 if (b->fd < 0) {
-                        b->last_connect_error = -errno;
+                        b->last_connect_error = errno;
                         zero(b->sockaddr);
                         continue;
                 }
@@ -544,9 +586,9 @@ static int bus_start_connect(sd_bus *b) {
                 r = connect(b->fd, &b->sockaddr.sa, b->sockaddr_size);
                 if (r < 0) {
                         if (errno == EINPROGRESS)
-                                return 0;
+                                return 1;
 
-                        b->last_connect_error = -errno;
+                        b->last_connect_error = errno;
                         close_nointr_nofail(b->fd);
                         b->fd = -1;
                         zero(b->sockaddr);
@@ -570,25 +612,25 @@ int sd_bus_open_system(sd_bus **ret) {
                 r = sd_bus_open_address(e, &b);
                 if (r < 0)
                         return r;
+        } else {
+                b = bus_new();
+                if (!b)
+                        return -ENOMEM;
 
-                b->send_hello = true;
-                *ret = b;
-                return r;
-        }
-
-        b = bus_new();
-        if (!b)
-                return -ENOMEM;
-
-        b->send_hello = true;
+                b->sockaddr.un.sun_family = AF_UNIX;
+                strncpy(b->sockaddr.un.sun_path, "/run/dbus/system_bus_socket", sizeof(b->sockaddr.un.sun_path));
+                b->sockaddr_size = offsetof(struct sockaddr_un, sun_path) + sizeof("/run/dbus/system_bus_socket") - 1;
 
-        b->sockaddr.un.sun_family = AF_UNIX;
-        strncpy(b->sockaddr.un.sun_path, "/run/dbus/system_bus_socket", sizeof(b->sockaddr.un.sun_path));
-        b->sockaddr_size = offsetof(struct sockaddr_un, sun_path) + sizeof("/run/dbus/system_bus_socket") - 1;
+                r = bus_start_connect(b);
+                if (r < 0) {
+                        bus_free(b);
+                        return r;
+                }
+        }
 
-        r = bus_start_connect(b);
+        r = bus_send_hello(b);
         if (r < 0) {
-                bus_free(b);
+                sd_bus_unref(b);
                 return r;
         }
 
@@ -610,33 +652,33 @@ int sd_bus_open_user(sd_bus **ret) {
                 r = sd_bus_open_address(e, &b);
                 if (r < 0)
                         return r;
+        } else {
+                e = getenv("XDG_RUNTIME_DIR");
+                if (!e)
+                        return -ENOENT;
 
-                b->send_hello = true;
-                *ret = b;
-                return r;
-        }
-
-        e = getenv("XDG_RUNTIME_DIR");
-        if (!e)
-                return -ENOENT;
-
-        l = strlen(e);
-        if (l + 4 > sizeof(b->sockaddr.un.sun_path))
-                return -E2BIG;
+                l = strlen(e);
+                if (l + 4 > sizeof(b->sockaddr.un.sun_path))
+                        return -E2BIG;
 
-        b = bus_new();
-        if (!b)
-                return -ENOMEM;
+                b = bus_new();
+                if (!b)
+                        return -ENOMEM;
 
-        b->send_hello = true;
+                b->sockaddr.un.sun_family = AF_UNIX;
+                memcpy(mempcpy(b->sockaddr.un.sun_path, e, l), "/bus", 4);
+                b->sockaddr_size = offsetof(struct sockaddr_un, sun_path) + l + 4;
 
-        b->sockaddr.un.sun_family = AF_UNIX;
-        memcpy(mempcpy(b->sockaddr.un.sun_path, e, l), "/bus", 4);
-        b->sockaddr_size = offsetof(struct sockaddr_un, sun_path) + l + 4;
+                r = bus_start_connect(b);
+                if (r < 0) {
+                        bus_free(b);
+                        return r;
+                }
+        }
 
-        r = bus_start_connect(b);
+        r = bus_send_hello(b);
         if (r < 0) {
-                bus_free(b);
+                sd_bus_unref(b);
                 return r;
         }
 
@@ -733,30 +775,52 @@ sd_bus *sd_bus_unref(sd_bus *bus) {
         return NULL;
 }
 
-int sd_bus_is_running(sd_bus *bus) {
+int sd_bus_is_open(sd_bus *bus) {
         if (!bus)
                 return -EINVAL;
 
-        if (bus->fd < 0)
-                return -ENOTCONN;
-
-        return bus->state == BUS_RUNNING;
+        return bus->fd >= 0;
 }
 
 int sd_bus_can_send(sd_bus *bus, char type) {
+        int r;
 
         if (!bus)
                 return -EINVAL;
 
-        if (type == SD_BUS_TYPE_UNIX_FD)
+        if (type == SD_BUS_TYPE_UNIX_FD) {
+                r = ensure_running(bus);
+                if (r < 0)
+                        return r;
+
                 return bus->can_fds;
+        }
 
         return bus_type_is_valid(type);
 }
 
+int sd_bus_get_peer(sd_bus *bus, sd_id128_t *peer) {
+        int r;
+
+        if (!bus)
+                return -EINVAL;
+        if (!peer)
+                return -EINVAL;
+
+        r = ensure_running(bus);
+        if (r < 0)
+                return r;
+
+        *peer = bus->peer;
+        return 0;
+}
+
 static int bus_seal_message(sd_bus *b, sd_bus_message *m) {
         assert(m);
 
+        if (m->header->version > b->message_version)
+                return -EPERM;
+
         if (m->sealed)
                 return 0;
 
@@ -773,6 +837,10 @@ static int message_write(sd_bus *bus, sd_bus_message *m, size_t *idx) {
         assert(bus);
         assert(m);
         assert(idx);
+        assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
+
+        if (*idx >= m->size)
+                return 0;
 
         n = m->n_iovec * sizeof(struct iovec);
         iov = alloca(n);
@@ -787,23 +855,40 @@ static int message_write(sd_bus *bus, sd_bus_message *m, size_t *idx) {
 
         k = sendmsg(bus->fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
         if (k < 0)
-                return -errno;
+                return errno == EAGAIN ? 0 : -errno;
 
         *idx += (size_t) k;
-        iovec_advance(iov, &j, *idx);
-
-        return j > m->n_iovec;
+        return 1;
 }
 
 static int message_read_need(sd_bus *bus, size_t *need) {
         uint32_t a, b;
         uint8_t e;
+        uint64_t sum;
 
         assert(bus);
         assert(need);
+        assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
+
+        if (bus->rbuffer_size < sizeof(struct bus_header)) {
+                *need = sizeof(struct bus_header) + 8;
+
+                /* Minimum message size:
+                 *
+                 * Header +
+                 *
+                 *  Method Call: +2 string headers
+                 *       Signal: +3 string headers
+                 * Method Error: +1 string headers
+                 *               +1 uint32 headers
+                 * Method Reply: +1 uint32 headers
+                 *
+                 * A string header is at least 9 bytes
+                 * A uint32 header is at least 8 bytes
+                 *
+                 * Hence the minimum message size of a valid message
+                 * is header + 8 bytes */
 
-        if (bus->rbuffer_size <= sizeof(struct bus_header)) {
-                *need = sizeof(struct bus_header);
                 return 0;
         }
 
@@ -818,9 +903,13 @@ static int message_read_need(sd_bus *bus, size_t *need) {
                 a = be32toh(a);
                 b = be32toh(b);
         } else
-                return -EIO;
+                return -EBADMSG;
 
-        *need = sizeof(struct bus_header) + ALIGN_TO(a, 8) + b;
+        sum = (uint64_t) sizeof(struct bus_header) + (uint64_t) ALIGN_TO(b, 8) + (uint64_t) a;
+        if (sum >= BUS_MESSAGE_SIZE_MAX)
+                return -ENOBUFS;
+
+        *need = (size_t) sum;
         return 0;
 }
 
@@ -832,10 +921,7 @@ static int message_make(sd_bus *bus, size_t size, sd_bus_message **m) {
         assert(bus);
         assert(m);
         assert(bus->rbuffer_size >= size);
-
-        t = new0(sd_bus_message, 1);
-        if (!t)
-                return -ENOMEM;
+        assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
 
         if (bus->rbuffer_size > size) {
                 b = memdup((const uint8_t*) bus->rbuffer + size, bus->rbuffer_size - size);
@@ -845,23 +931,15 @@ static int message_make(sd_bus *bus, size_t size, sd_bus_message **m) {
                 }
         }
 
-        t->n_ref = 1;
-
-        t->header = bus->rbuffer;
-        t->free_header = true;
-
-        t->fields = (uint8_t*) bus->rbuffer + sizeof(struct bus_header);
-        t->body = (uint8_t*) bus->rbuffer + sizeof(struct bus_header) + ALIGN_TO(BUS_MESSAGE_BODY_SIZE(t), 8);
-
-        bus->rbuffer = b;
-        bus->rbuffer_size -= size;
-
-        r = bus_message_parse(t);
+        r = bus_message_from_malloc(bus->rbuffer, size, &t);
         if (r < 0) {
-                sd_bus_message_unref(t);
+                free(b);
                 return r;
         }
 
+        bus->rbuffer = b;
+        bus->rbuffer_size -= size;
+
         *m = t;
         return 1;
 }
@@ -876,6 +954,7 @@ static int message_read(sd_bus *bus, sd_bus_message **m) {
 
         assert(bus);
         assert(m);
+        assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
 
         r = message_read_need(bus, &need);
         if (r < 0)
@@ -888,6 +967,8 @@ static int message_read(sd_bus *bus, sd_bus_message **m) {
         if (!b)
                 return -ENOMEM;
 
+        bus->rbuffer = b;
+
         zero(iov);
         iov.iov_base = (uint8_t*) bus->rbuffer + bus->rbuffer_size;
         iov.iov_len = need - bus->rbuffer_size;
@@ -909,13 +990,14 @@ static int message_read(sd_bus *bus, sd_bus_message **m) {
         if (bus->rbuffer_size >= need)
                 return message_make(bus, need, m);
 
-        return 0;
+        return 1;
 }
 
 static int dispatch_wqueue(sd_bus *bus) {
-        int r, c = 0;
+        int r, ret = 0;
 
         assert(bus);
+        assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
 
         if (bus->fd < 0)
                 return -ENOTCONN;
@@ -927,9 +1009,9 @@ static int dispatch_wqueue(sd_bus *bus) {
                         sd_bus_close(bus);
                         return r;
                 } else if (r == 0)
-                        /* Wasn't fully written yet... */
-                        break;
-                else {
+                        /* Didn't do anything this time */
+                        return ret;
+                else if (bus->windex >= bus->wqueue[0]->size) {
                         /* Fully written. Let's drop the entry from
                          * the queue.
                          *
@@ -945,18 +1027,20 @@ static int dispatch_wqueue(sd_bus *bus) {
                         memmove(bus->wqueue, bus->wqueue + 1, sizeof(sd_bus_message*) * bus->wqueue_size);
                         bus->windex = 0;
 
-                        c++;
+                        ret = 1;
                 }
         }
 
-        return c;
+        return ret;
 }
 
 static int dispatch_rqueue(sd_bus *bus, sd_bus_message **m) {
-        int r;
+        sd_bus_message *z;
+        int r, ret = 0;
 
         assert(bus);
         assert(m);
+        assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO);
 
         if (bus->fd < 0)
                 return -ENOTCONN;
@@ -971,13 +1055,20 @@ static int dispatch_rqueue(sd_bus *bus, sd_bus_message **m) {
         }
 
         /* Try to read a new message */
-        r = message_read(bus, m);
-        if (r < 0) {
-                sd_bus_close(bus);
-                return r;
-        }
+        do {
+                r = message_read(bus, &z);
+                if (r < 0) {
+                        sd_bus_close(bus);
+                        return r;
+                }
+                if (r == 0)
+                        return ret;
 
-        return r;
+                r = 1;
+        } while (!z);
+
+        *m = z;
+        return 1;
 }
 
 int sd_bus_send(sd_bus *bus, sd_bus_message *m, uint64_t *serial) {
@@ -989,8 +1080,11 @@ int sd_bus_send(sd_bus *bus, sd_bus_message *m, uint64_t *serial) {
                 return -ENOTCONN;
         if (!m)
                 return -EINVAL;
-        if (m->header->version > bus->message_version)
-                return -EPERM;
+
+        /* If the serial number isn't kept, then we know that no reply
+         * is expected */
+        if (!serial && !m->sealed)
+                m->header->flags |= SD_BUS_MESSAGE_NO_REPLY_EXPECTED;
 
         r = bus_seal_message(bus, m);
         if (r < 0)
@@ -1001,14 +1095,14 @@ int sd_bus_send(sd_bus *bus, sd_bus_message *m, uint64_t *serial) {
         if (m->dont_send && !serial)
                 return 0;
 
-        if (bus->wqueue_size <= 0) {
+        if ((bus->state == BUS_RUNNING || bus->state == BUS_HELLO) && bus->wqueue_size <= 0) {
                 size_t idx = 0;
 
                 r = message_write(bus, m, &idx);
                 if (r < 0) {
                         sd_bus_close(bus);
                         return r;
-                } else if (r == 0)  {
+                } else if (idx < m->size)  {
                         /* Wasn't fully written. So let's remember how
                          * much was written. Note that the first entry
                          * of the wqueue array is always allocated so
@@ -1023,7 +1117,7 @@ int sd_bus_send(sd_bus *bus, sd_bus_message *m, uint64_t *serial) {
 
                 /* Just append it to the queue. */
 
-                if (bus->wqueue_size >= WQUEUE_MAX)
+                if (bus->wqueue_size >= BUS_WQUEUE_MAX)
                         return -ENOBUFS;
 
                 q = realloc(bus->wqueue, sizeof(sd_bus_message*) * (bus->wqueue_size + 1));
@@ -1045,11 +1139,29 @@ static usec_t calc_elapse(uint64_t usec) {
                 return 0;
 
         if (usec == 0)
-                usec = SD_BUS_DEFAULT_TIMEOUT;
+                usec = BUS_DEFAULT_TIMEOUT;
 
         return now(CLOCK_MONOTONIC) + usec;
 }
 
+static int timeout_compare(const void *a, const void *b) {
+        const struct reply_callback *x = a, *y = b;
+
+        if (x->timeout != 0 && y->timeout == 0)
+                return -1;
+
+        if (x->timeout == 0 && y->timeout != 0)
+                return 1;
+
+        if (x->timeout < y->timeout)
+                return -1;
+
+        if (x->timeout > y->timeout)
+                return 1;
+
+        return 0;
+}
+
 int sd_bus_send_with_reply(
                 sd_bus *bus,
                 sd_bus_message *m,
@@ -1063,14 +1175,26 @@ int sd_bus_send_with_reply(
 
         if (!bus)
                 return -EINVAL;
-        if (!bus->fd < 0)
+        if (bus->fd < 0)
                 return -ENOTCONN;
         if (!m)
                 return -EINVAL;
         if (!callback)
                 return -EINVAL;
-        if (!m->header->type != SD_BUS_MESSAGE_TYPE_METHOD_CALL)
+        if (m->header->type != SD_BUS_MESSAGE_TYPE_METHOD_CALL)
                 return -EINVAL;
+        if (m->header->flags & SD_BUS_MESSAGE_NO_REPLY_EXPECTED)
+                return -EINVAL;
+
+        r = hashmap_ensure_allocated(&bus->reply_callbacks, uint64_hash_func, uint64_compare_func);
+        if (r < 0)
+                return r;
+
+        if (usec != (uint64_t) -1) {
+                r = prioq_ensure_allocated(&bus->reply_callbacks_prioq, timeout_compare);
+                if (r < 0)
+                        return r;
+        }
 
         r = bus_seal_message(bus, m);
         if (r < 0)
@@ -1091,10 +1215,18 @@ int sd_bus_send_with_reply(
                 return r;
         }
 
+        if (c->timeout != 0) {
+                r = prioq_put(bus->reply_callbacks_prioq, c, &c->prioq_idx);
+                if (r < 0) {
+                        c->timeout = 0;
+                        sd_bus_send_with_reply_cancel(bus, c->serial);
+                        return r;
+                }
+        }
+
         r = sd_bus_send(bus, m, serial);
         if (r < 0) {
-                hashmap_remove(bus->reply_callbacks, &c->serial);
-                free(c);
+                sd_bus_send_with_reply_cancel(bus, c->serial);
                 return r;
         }
 
@@ -1102,7 +1234,7 @@ int sd_bus_send_with_reply(
 }
 
 int sd_bus_send_with_reply_cancel(sd_bus *bus, uint64_t serial) {
-        struct reply_callbacks *c;
+        struct reply_callback *c;
 
         if (!bus)
                 return -EINVAL;
@@ -1113,10 +1245,36 @@ int sd_bus_send_with_reply_cancel(sd_bus *bus, uint64_t serial) {
         if (!c)
                 return 0;
 
+        if (c->timeout != 0)
+                prioq_remove(bus->reply_callbacks_prioq, c, &c->prioq_idx);
+
         free(c);
         return 1;
 }
 
+static int ensure_running(sd_bus *bus) {
+        int r;
+
+        assert(bus);
+
+        if (bus->state == BUS_RUNNING)
+                return 1;
+
+        for (;;) {
+                r = sd_bus_process(bus, NULL);
+                if (r < 0)
+                        return r;
+                if (bus->state == BUS_RUNNING)
+                        return 1;
+                if (r > 0)
+                        continue;
+
+                r = sd_bus_wait(bus, (uint64_t) -1);
+                if (r < 0)
+                        return r;
+        }
+}
+
 int sd_bus_send_with_reply_and_block(
                 sd_bus *bus,
                 sd_bus_message *m,
@@ -1131,15 +1289,21 @@ int sd_bus_send_with_reply_and_block(
 
         if (!bus)
                 return -EINVAL;
-        if (!bus->fd < 0)
+        if (bus->fd < 0)
                 return -ENOTCONN;
         if (!m)
                 return -EINVAL;
-        if (!m->header->type != SD_BUS_MESSAGE_TYPE_METHOD_CALL)
+        if (m->header->type != SD_BUS_MESSAGE_TYPE_METHOD_CALL)
+                return -EINVAL;
+        if (m->header->flags & SD_BUS_MESSAGE_NO_REPLY_EXPECTED)
                 return -EINVAL;
-        if (sd_bus_error_is_set(error))
+        if (bus_error_is_dirty(error))
                 return -EINVAL;
 
+        r = ensure_running(bus);
+        if (r < 0)
+                return r;
+
         r = sd_bus_send(bus, m, &serial);
         if (r < 0)
                 return r;
@@ -1148,11 +1312,14 @@ int sd_bus_send_with_reply_and_block(
 
         for (;;) {
                 usec_t left;
-                sd_bus_message *incoming;
+                sd_bus_message *incoming = NULL;
 
                 if (!room) {
                         sd_bus_message **q;
 
+                        if (bus->rqueue_size >= BUS_RQUEUE_MAX)
+                                return -ENOBUFS;
+
                         /* Make sure there's room for queuing this
                          * locally, before we read the message */
 
@@ -1167,7 +1334,8 @@ int sd_bus_send_with_reply_and_block(
                 r = message_read(bus, &incoming);
                 if (r < 0)
                         return r;
-                if (r > 0) {
+                if (incoming) {
+
                         if (incoming->reply_serial == serial) {
                                 /* Found a match! */
 
@@ -1202,6 +1370,8 @@ int sd_bus_send_with_reply_and_block(
                         /* Try to read more, right-away */
                         continue;
                 }
+                if (r != 0)
+                        continue;
 
                 if (timeout > 0) {
                         usec_t n;
@@ -1214,7 +1384,7 @@ int sd_bus_send_with_reply_and_block(
                 } else
                         left = (uint64_t) -1;
 
-                r = sd_bus_wait(bus, left);
+                r = bus_poll(bus, true, left);
                 if (r < 0)
                         return r;
 
@@ -1229,7 +1399,7 @@ int sd_bus_get_fd(sd_bus *bus) {
                 return -EINVAL;
 
         if (bus->fd < 0)
-                return -EINVAL;
+                return -ENOTCONN;
 
         return bus->fd;
 }
@@ -1239,13 +1409,19 @@ int sd_bus_get_events(sd_bus *bus) {
 
         if (!bus)
                 return -EINVAL;
-
         if (bus->fd < 0)
-                return -EINVAL;
+                return -ENOTCONN;
 
         if (bus->state == BUS_OPENING)
                 flags |= POLLOUT;
-        else if (bus->state == BUS_RUNNING || bus->state == BUS_HELLO) {
+        else if (bus->state == BUS_AUTHENTICATING) {
+
+                if (bus->auth_index < ELEMENTSOF(bus->auth_iovec))
+                        flags |= POLLOUT;
+
+                flags |= POLLIN;
+
+        } else if (bus->state == BUS_RUNNING || bus->state == BUS_HELLO) {
                 if (bus->rqueue_size <= 0)
                         flags |= POLLIN;
                 if (bus->wqueue_size > 0)
@@ -1255,10 +1431,148 @@ int sd_bus_get_events(sd_bus *bus) {
         return flags;
 }
 
+int sd_bus_get_timeout(sd_bus *bus, uint64_t *timeout_usec) {
+        struct reply_callback *c;
+
+        if (!bus)
+                return -EINVAL;
+        if (!timeout_usec)
+                return -EINVAL;
+        if (bus->fd < 0)
+                return -ENOTCONN;
+
+        if (bus->state == BUS_AUTHENTICATING) {
+                *timeout_usec = bus->auth_timeout;
+                return 1;
+        }
+
+        if (bus->state != BUS_RUNNING && bus->state != BUS_HELLO)
+                return 0;
+
+        c = prioq_peek(bus->reply_callbacks_prioq);
+        if (!c)
+                return 0;
+
+        *timeout_usec = c->timeout;
+        return 1;
+}
+
+static int process_timeout(sd_bus *bus) {
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        struct reply_callback *c;
+        usec_t n;
+        int r;
+
+        assert(bus);
+
+        c = prioq_peek(bus->reply_callbacks_prioq);
+        if (!c)
+                return 0;
+
+        n = now(CLOCK_MONOTONIC);
+        if (c->timeout > n)
+                return 0;
+
+        assert_se(prioq_pop(bus->reply_callbacks_prioq) == c);
+        hashmap_remove(bus->reply_callbacks, &c->serial);
+
+        r = c->callback(bus, ETIMEDOUT, NULL, c->userdata);
+        free(c);
+
+        return r < 0 ? r : 1;
+}
+
+static int process_builtin(sd_bus *bus, sd_bus_message *m) {
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        int r;
+
+        assert(bus);
+        assert(m);
+
+        if (m->header->type != SD_BUS_MESSAGE_TYPE_METHOD_CALL)
+                return 0;
+
+        if (!streq_ptr(m->interface, "org.freedesktop.DBus.Peer"))
+                return 0;
+
+        if (m->header->flags & SD_BUS_MESSAGE_NO_REPLY_EXPECTED)
+                return 1;
+
+        if (streq_ptr(m->member, "Ping"))
+                r = sd_bus_message_new_method_return(bus, m, &reply);
+        else if (streq_ptr(m->member, "GetMachineId")) {
+                sd_id128_t id;
+                char sid[33];
+
+                r = sd_id128_get_machine(&id);
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_new_method_return(bus, m, &reply);
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append(reply, "s", sd_id128_to_string(id, sid));
+        } else {
+                _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_INIT;
+
+                sd_bus_error_set(&error,
+                                 "org.freedesktop.DBus.Error.UnknownMethod",
+                                 "Unknown method '%s' on interface '%s'.", m->member, m->interface);
+
+                r = sd_bus_message_new_method_error(bus, m, &error, &reply);
+        }
+
+        if (r < 0)
+                return r;
+
+        r = sd_bus_send(bus, reply, NULL);
+        if (r < 0)
+                return r;
+
+        return 1;
+}
+
+static int process_message(sd_bus *bus, sd_bus_message *m) {
+        struct filter_callback *l;
+        int r;
+
+        assert(bus);
+        assert(m);
+
+        if (m->header->type == SD_BUS_MESSAGE_TYPE_METHOD_RETURN || m->header->type == SD_BUS_MESSAGE_TYPE_METHOD_ERROR) {
+                struct reply_callback *c;
+
+                c = hashmap_remove(bus->reply_callbacks, &m->reply_serial);
+                if (c) {
+                        if (c->timeout != 0)
+                                prioq_remove(bus->reply_callbacks_prioq, c, &c->prioq_idx);
+
+                        r = c->callback(bus, 0, m, c->userdata);
+                        free(c);
+
+                        if (r != 0)
+                                return r;
+                }
+        }
+
+        LIST_FOREACH(callbacks, l, bus->filter_callbacks) {
+                r = l->callback(bus, 0, m, l->userdata);
+                if (r != 0)
+                        return r;
+        }
+
+        return process_builtin(bus, m);
+}
+
 int sd_bus_process(sd_bus *bus, sd_bus_message **ret) {
-        sd_bus_message *m;
         int r;
 
+        /* Returns 0 when we didn't do anything. This should cause the
+         * caller to invoke sd_bus_wait() before returning the next
+         * time. Returns > 0 when we did something, which possibly
+         * means *ret is filled in with an unprocessed message. */
+
         if (!bus)
                 return -EINVAL;
         if (bus->fd < 0)
@@ -1276,107 +1590,153 @@ int sd_bus_process(sd_bus *bus, sd_bus_message **ret) {
                         return -errno;
 
                 if (p.revents & (POLLOUT|POLLERR|POLLHUP)) {
-                        int error;
+                        int error = 0;
                         socklen_t slen = sizeof(error);
 
                         r = getsockopt(bus->fd, SOL_SOCKET, SO_ERROR, &error, &slen);
                         if (r < 0)
-                                return -errno;
-
-                        if (error != 0)
-                                bus->last_connect_error = -error;
+                                bus->last_connect_error = errno;
+                        else if (error != 0)
+                                bus->last_connect_error = error;
                         else if (p.revents & (POLLERR|POLLHUP))
-                                bus->last_connect_error = -ECONNREFUSED;
-                        else
-                                return bus_start_auth(bus);
+                                bus->last_connect_error = ECONNREFUSED;
+                        else {
+                                r = bus_start_auth(bus);
+                                goto null_message;
+                        }
 
                         /* Try next address */
-                        return bus_start_connect(bus);
+                        r = bus_start_connect(bus);
+                        goto null_message;
                 }
 
-                return 0;
+                r = 0;
+                goto null_message;
 
         } else if (bus->state == BUS_AUTHENTICATING) {
 
+                if (now(CLOCK_MONOTONIC) >= bus->auth_timeout)
+                        return -ETIMEDOUT;
+
                 r = bus_write_auth(bus);
-                if (r < 0)
-                        return r;
+                if (r != 0)
+                        goto null_message;
 
                 r = bus_read_auth(bus);
-                if (r <= 0)
-                        return r;
-
-                return bus_start_running(bus);
+                goto null_message;
 
         } else if (bus->state == BUS_RUNNING || bus->state == BUS_HELLO) {
-                struct filter_callback *l;
+                _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+                int k;
+
+                r = process_timeout(bus);
+                if (r != 0)
+                        goto null_message;
 
                 r = dispatch_wqueue(bus);
-                if (r < 0)
-                        return r;
+                if (r != 0)
+                        goto null_message;
 
+                k = r;
                 r = dispatch_rqueue(bus, &m);
-                if (r <= 0)
+                if (r < 0)
                         return r;
-
-                if (m->header->type == SD_BUS_MESSAGE_TYPE_METHOD_CALL || m->header->type == SD_BUS_MESSAGE_TYPE_METHOD_RETURN) {
-                        struct reply_callback *c;
-
-                        c = hashmap_remove(bus->reply_callbacks, &m->reply_serial);
-                        if (c) {
-                                r = c->callback(bus, m, c->userdata);
-                                free(c);
-
-                                if (r != 0) {
-                                        sd_bus_message_unref(m);
-                                        return r < 0 ? r : 0;
-                                }
-                        }
+                if (!m) {
+                        if (r == 0)
+                                r = k;
+                        goto null_message;
                 }
 
-                LIST_FOREACH(callbacks, l, bus->filter_callbacks) {
-                        r = l->callback(bus, m, l->userdata);
-                        if (r != 0) {
-                                sd_bus_message_unref(m);
-                                return r < 0 ? r : 0;
-                        }
-                }
+                r = process_message(bus, m);
+                if (r != 0)
+                        goto null_message;
 
                 if (ret) {
                         *ret = m;
+                        m = NULL;
                         return 1;
                 }
 
-                sd_bus_message_unref(m);
-                return 0;
+                if (m->header->type == SD_BUS_MESSAGE_TYPE_METHOD_CALL) {
+                        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+                        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_INIT;
+
+                        sd_bus_error_set(&error, "org.freedesktop.DBus.Error.UnknownObject", "Unknown object '%s'.", m->path);
+
+                        r = sd_bus_message_new_method_error(bus, m, &error, &reply);
+                        if (r < 0)
+                                return r;
+
+                        r = sd_bus_send(bus, reply, NULL);
+                        if (r < 0)
+                                return r;
+                }
+
+                return 1;
         }
 
-        return -ENOTSUP;
+        assert_not_reached("Unknown state");
+
+null_message:
+        if (r >= 0 && ret)
+                *ret = NULL;
+
+        return r;
 }
 
-int sd_bus_wait(sd_bus *bus, uint64_t timeout_usec) {
+static int bus_poll(sd_bus *bus, bool need_more, uint64_t timeout_usec) {
         struct pollfd p;
         int r, e;
         struct timespec ts;
+        usec_t until, m;
+
+        assert(bus);
 
-        if (!bus)
-                return -EINVAL;
         if (bus->fd < 0)
-                return -ECONNREFUSED;
+                return -ENOTCONN;
 
         e = sd_bus_get_events(bus);
         if (e < 0)
                 return e;
 
+        if (need_more)
+                e |= POLLIN;
+
+        r = sd_bus_get_timeout(bus, &until);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                m = (uint64_t) -1;
+        else {
+                usec_t n;
+                n = now(CLOCK_MONOTONIC);
+                m = until > n ? until - n : 0;
+        }
+
+        if (timeout_usec != (uint64_t) -1 && (m == (uint64_t) -1 || timeout_usec < m))
+                m = timeout_usec;
+
         zero(p);
         p.fd = bus->fd;
         p.events = e;
 
-        r = ppoll(&p, 1, timeout_usec == (uint64_t) -1 ? NULL : timespec_store(&ts, timeout_usec), NULL);
+        r = ppoll(&p, 1, m == (uint64_t) -1 ? NULL : timespec_store(&ts, m), NULL);
         if (r < 0)
+                return -errno;
+
+        return r > 0 ? 1 : 0;
+}
+
+int sd_bus_wait(sd_bus *bus, uint64_t timeout_usec) {
+
+        if (!bus)
                 return -EINVAL;
+        if (bus->fd < 0)
+                return -ENOTCONN;
+        if (bus->rqueue_size > 0)
+                return 0;
 
-        return r;
+        return bus_poll(bus, false, timeout_usec);
 }
 
 int sd_bus_flush(sd_bus *bus) {
@@ -1387,7 +1747,11 @@ int sd_bus_flush(sd_bus *bus) {
         if (bus->fd < 0)
                 return -ENOTCONN;
 
-        if (bus->state == BUS_RUNNING && bus->wqueue_size <= 0)
+        r = ensure_running(bus);
+        if (r < 0)
+                return r;
+
+        if (bus->wqueue_size <= 0)
                 return 0;
 
         for (;;) {
@@ -1395,10 +1759,10 @@ int sd_bus_flush(sd_bus *bus) {
                 if (r < 0)
                         return r;
 
-                if (bus->state == BUS_RUNNING && bus->wqueue_size <= 0)
+                if (bus->wqueue_size <= 0)
                         return 0;
 
-                r = sd_bus_wait(bus, (uint64_t) -1);
+                r = bus_poll(bus, false, (uint64_t) -1);
                 if (r < 0)
                         return r;
         }