chiark / gitweb /
bus: parse uid/gid/pid/tid meta data from kdbus messages
[elogind.git] / src / libsystemd-bus / bus-message.c
index fb63a2d1cf34b6bffda27b54dd372cc51d917f3f..092654ff4586deae02082fe6a96cc4f17e0e5dfc 100644 (file)
@@ -25,6 +25,7 @@
 #include "util.h"
 #include "utf8.h"
 #include "strv.h"
+#include "time-util.h"
 
 #include "sd-bus.h"
 #include "bus-message.h"
@@ -32,7 +33,6 @@
 #include "bus-type.h"
 #include "bus-signature.h"
 
-static int message_parse_fields(sd_bus_message *m);
 static int message_append_basic(sd_bus_message *m, char type, const void *p, const void **stored);
 
 static void reset_containers(sd_bus_message *m) {
@@ -62,6 +62,9 @@ static void message_free(sd_bus_message *m) {
         if (m->free_body)
                 free(m->body);
 
+        if (m->free_kdbus)
+                free(m->kdbus);
+
         if (m->free_fds) {
                 close_many(m->fds, m->n_fds);
                 free(m->fds);
@@ -225,19 +228,19 @@ static int message_append_field_uint32(sd_bus_message *m, uint8_t h, uint32_t x)
         return 0;
 }
 
-int bus_message_from_malloc(
+int bus_message_from_header(
                 void *buffer,
                 size_t length,
                 int *fds,
                 unsigned n_fds,
                 const struct ucred *ucred,
                 const char *label,
+                size_t extra,
                 sd_bus_message **ret) {
 
         sd_bus_message *m;
         struct bus_header *h;
-        size_t total, fs, bs, label_sz, a;
-        int r;
+        size_t a, label_sz;
 
         assert(buffer || length <= 0);
         assert(fds || n_fds <= 0);
@@ -256,24 +259,16 @@ int bus_message_from_malloc(
         if (h->type == _SD_BUS_MESSAGE_TYPE_INVALID)
                 return -EBADMSG;
 
-        if (h->endian == SD_BUS_NATIVE_ENDIAN) {
-                fs = h->fields_size;
-                bs = h->body_size;
-        } else if (h->endian == SD_BUS_REVERSE_ENDIAN) {
-                fs = bswap_32(h->fields_size);
-                bs = bswap_32(h->body_size);
-        } else
+        if (h->endian != SD_BUS_LITTLE_ENDIAN &&
+            h->endian != SD_BUS_BIG_ENDIAN)
                 return -EBADMSG;
 
-        total = sizeof(struct bus_header) + ALIGN_TO(fs, 8) + bs;
-        if (length != total)
-                return -EBADMSG;
+        a = ALIGN(sizeof(sd_bus_message)) + ALIGN(extra);
 
         if (label) {
                 label_sz = strlen(label);
-                a = ALIGN(sizeof(sd_bus_message)) + label_sz + 1;
-        } else
-                a = sizeof(sd_bus_message);
+                a += label_sz + 1;
+        }
 
         m = malloc0(a);
         if (!m)
@@ -282,8 +277,6 @@ int bus_message_from_malloc(
         m->n_ref = 1;
         m->sealed = true;
         m->header = h;
-        m->fields = (uint8_t*) buffer + sizeof(struct bus_header);
-        m->body = (uint8_t*) buffer + sizeof(struct bus_header) + ALIGN_TO(fs, 8);
         m->fds = fds;
         m->n_fds = n_fds;
 
@@ -295,16 +288,43 @@ int bus_message_from_malloc(
         }
 
         if (label) {
-                m->label = (char*) m + ALIGN(sizeof(sd_bus_message));
+                m->label = (char*) m + ALIGN(sizeof(sd_bus_message)) + ALIGN(extra);
                 memcpy(m->label, label, label_sz + 1);
         }
 
+        *ret = m;
+        return 0;
+}
+
+int bus_message_from_malloc(
+                void *buffer,
+                size_t length,
+                int *fds,
+                unsigned n_fds,
+                const struct ucred *ucred,
+                const char *label,
+                sd_bus_message **ret) {
+
+        sd_bus_message *m;
+        int r;
+
+        r = bus_message_from_header(buffer, length, fds, n_fds, ucred, label, 0, &m);
+        if (r < 0)
+                return r;
+
+        if (length != BUS_MESSAGE_SIZE(m)) {
+                r = -EBADMSG;
+                goto fail;
+        }
+
+        m->fields = (uint8_t*) buffer + sizeof(struct bus_header);
+        m->body = (uint8_t*) buffer + sizeof(struct bus_header) + ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m));
+
         m->n_iovec = 1;
         m->iovec[0].iov_base = buffer;
         m->iovec[0].iov_len = length;
-        m->size = length;
 
-        r = message_parse_fields(m);
+        r = bus_message_parse_fields(m);
         if (r < 0)
                 goto fail;
 
@@ -1710,18 +1730,13 @@ int sd_bus_message_read_basic(sd_bus_message *m, char type, void *p) {
                         break;
 
                 case SD_BUS_TYPE_UNIX_FD: {
-                        int copy;
                         uint32_t j;
 
                         j = BUS_MESSAGE_BSWAP32(m, *(uint32_t*) q);
                         if (j >= m->n_fds)
                                 return -EBADMSG;
 
-                        copy = fcntl(m->fds[j], F_DUPFD_CLOEXEC, 3);
-                        if (copy < 0)
-                                return -errno;
-
-                        *(int*) p = copy;
+                        *(int*) p = m->fds[j];
                         break;
                 }
 
@@ -2606,7 +2621,7 @@ static int message_skip_fields(
         }
 }
 
-static int message_parse_fields(sd_bus_message *m) {
+int bus_message_parse_fields(sd_bus_message *m) {
         size_t ri;
         int r;
         uint32_t unix_fds = 0;
@@ -2799,42 +2814,6 @@ static int message_parse_fields(sd_bus_message *m) {
         return 0;
 }
 
-static void setup_iovec(sd_bus_message *m) {
-        assert(m);
-        assert(m->sealed);
-
-        m->n_iovec = 0;
-        m->size = 0;
-
-        m->iovec[m->n_iovec].iov_base = m->header;
-        m->iovec[m->n_iovec].iov_len = sizeof(*m->header);
-        m->size += m->iovec[m->n_iovec].iov_len;
-        m->n_iovec++;
-
-        if (m->fields) {
-                m->iovec[m->n_iovec].iov_base = m->fields;
-                m->iovec[m->n_iovec].iov_len = m->header->fields_size;
-                m->size += m->iovec[m->n_iovec].iov_len;
-                m->n_iovec++;
-
-                if (m->header->fields_size % 8 != 0) {
-                        static const uint8_t padding[7] = { 0, 0, 0, 0, 0, 0, 0 };
-
-                        m->iovec[m->n_iovec].iov_base = (void*) padding;
-                        m->iovec[m->n_iovec].iov_len = 8 - m->header->fields_size % 8;
-                        m->size += m->iovec[m->n_iovec].iov_len;
-                        m->n_iovec++;
-                }
-        }
-
-        if (m->body) {
-                m->iovec[m->n_iovec].iov_base = m->body;
-                m->iovec[m->n_iovec].iov_len = m->header->body_size;
-                m->size += m->iovec[m->n_iovec].iov_len;
-                m->n_iovec++;
-        }
-}
-
 int bus_message_seal(sd_bus_message *m, uint64_t serial) {
         int r;
 
@@ -2862,8 +2841,6 @@ int bus_message_seal(sd_bus_message *m, uint64_t serial) {
         m->header->serial = serial;
         m->sealed = true;
 
-        setup_iovec(m);
-
         return 0;
 }
 
@@ -2925,6 +2902,16 @@ int bus_message_dump(sd_bus_message *m) {
                strna(m->error.message),
                yes_no(m->sealed));
 
+        if (m->pid != 0)
+                printf("\tpid=%lu\n", (unsigned long) m->pid);
+        if (m->tid != 0)
+                printf("\ttid=%lu\n", (unsigned long) m->tid);
+        if (m->uid_valid)
+                printf("\tuid=%lu\n", (unsigned long) m->uid);
+        if (m->gid_valid)
+                printf("\tgid=%lu\n", (unsigned long) m->gid);
+
+
         r = sd_bus_message_rewind(m, true);
         if (r < 0) {
                 log_error("Failed to rewind: %s", strerror(-r));
@@ -3079,22 +3066,31 @@ int bus_message_dump(sd_bus_message *m) {
 
 int bus_message_get_blob(sd_bus_message *m, void **buffer, size_t *sz) {
         size_t total;
-        unsigned i;
         void *p, *e;
 
         assert(m);
         assert(buffer);
         assert(sz);
 
-        for (i = 0, total = 0; i < m->n_iovec; i++)
-                total += m->iovec[i].iov_len;
+        total = BUS_MESSAGE_SIZE(m);
 
         p = malloc(total);
         if (!p)
                 return -ENOMEM;
 
-        for (i = 0, e = p; i < m->n_iovec; i++)
-                e = mempcpy(e, m->iovec[i].iov_base, m->iovec[i].iov_len);
+        e = mempcpy(p, m->header, sizeof(*m->header));
+
+        if (m->fields) {
+                e = mempcpy(e, m->fields, m->header->fields_size);
+
+                if (m->header->fields_size % 8 != 0)
+                        e = mempset(e, 0, 8 - (m->header->fields_size % 8));
+        }
+
+        if (m->body)
+                e = mempcpy(e, m->body, m->header->body_size);
+
+        assert(total == (size_t) ((uint8_t*) e - (uint8_t*) p));
 
         *buffer = p;
         *sz = total;
@@ -3167,3 +3163,22 @@ const char* bus_message_get_arg(sd_bus_message *m, unsigned i) {
 
         return t;
 }
+
+int bus_header_size(struct bus_header *h, size_t *sum) {
+        size_t fs, bs;
+
+        assert(h);
+        assert(sum);
+
+        if (h->endian == SD_BUS_NATIVE_ENDIAN) {
+                fs = h->fields_size;
+                bs = h->body_size;
+        } else if (h->endian == SD_BUS_REVERSE_ENDIAN) {
+                fs = bswap_32(h->fields_size);
+                bs = bswap_32(h->body_size);
+        } else
+                return -EBADMSG;
+
+        *sum = sizeof(struct bus_header) + ALIGN8(fs) + bs;
+        return 0;
+}