chiark / gitweb /
rtnl: make checks for default routes more strict
[elogind.git] / src / libsystemd / sd-rtnl / rtnl-message.c
index b501a52cf1db4280cfdca35c42c1ee786eaf62de..a2f75471b4cff69e2aaa4da844ed3346f5038751 100644 (file)
@@ -36,6 +36,8 @@
 #define GET_CONTAINER(m, i) ((i) < (m)->n_containers ? (struct rtattr*)((uint8_t*)(m)->hdr + (m)->container_offsets[i]) : NULL)
 #define PUSH_CONTAINER(m, new) (m)->container_offsets[(m)->n_containers ++] = (uint8_t*)(new) - (uint8_t*)(m)->hdr;
 
+#define RTA_TYPE(rta) ((rta)->rta_type & NLA_TYPE_MASK)
+
 static int message_new_empty(sd_rtnl *rtnl, sd_rtnl_message **ret) {
         sd_rtnl_message *m;
 
@@ -126,6 +128,51 @@ int sd_rtnl_message_route_set_scope(sd_rtnl_message *m, unsigned char scope) {
         return 0;
 }
 
+int sd_rtnl_message_route_get_family(sd_rtnl_message *m, int *family) {
+        struct rtmsg *rtm;
+
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
+        assert_return(rtnl_message_type_is_route(m->hdr->nlmsg_type), -EINVAL);
+        assert_return(family, -EINVAL);
+
+        rtm = NLMSG_DATA(m->hdr);
+
+        *family = rtm->rtm_family;
+
+        return 0;
+}
+
+int sd_rtnl_message_route_get_dst_len(sd_rtnl_message *m, unsigned char *dst_len) {
+        struct rtmsg *rtm;
+
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
+        assert_return(rtnl_message_type_is_route(m->hdr->nlmsg_type), -EINVAL);
+        assert_return(dst_len, -EINVAL);
+
+        rtm = NLMSG_DATA(m->hdr);
+
+        *dst_len = rtm->rtm_dst_len;
+
+        return 0;
+}
+
+int sd_rtnl_message_route_get_src_len(sd_rtnl_message *m, unsigned char *src_len) {
+        struct rtmsg *rtm;
+
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
+        assert_return(rtnl_message_type_is_route(m->hdr->nlmsg_type), -EINVAL);
+        assert_return(src_len, -EINVAL);
+
+        rtm = NLMSG_DATA(m->hdr);
+
+        *src_len = rtm->rtm_src_len;
+
+        return 0;
+}
+
 int sd_rtnl_message_new_route(sd_rtnl *rtnl, sd_rtnl_message **ret,
                               uint16_t nlmsg_type, int rtm_family,
                               unsigned char rtm_protocol) {
@@ -133,7 +180,8 @@ int sd_rtnl_message_new_route(sd_rtnl *rtnl, sd_rtnl_message **ret,
         int r;
 
         assert_return(rtnl_message_type_is_route(nlmsg_type), -EINVAL);
-        assert_return(rtm_family == AF_INET || rtm_family == AF_INET6, -EINVAL);
+        assert_return((nlmsg_type == RTM_GETROUTE && rtm_family == AF_UNSPEC) ||
+                      rtm_family == AF_INET || rtm_family == AF_INET6, -EINVAL);
         assert_return(ret, -EINVAL);
 
         r = message_new(rtnl, ret, nlmsg_type);
@@ -154,6 +202,59 @@ int sd_rtnl_message_new_route(sd_rtnl *rtnl, sd_rtnl_message **ret,
         return 0;
 }
 
+int sd_rtnl_message_neigh_get_family(sd_rtnl_message *m, int *family) {
+        struct ndmsg *ndm;
+
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
+        assert_return(rtnl_message_type_is_neigh(m->hdr->nlmsg_type), -EINVAL);
+        assert_return(family, -EINVAL);
+
+        ndm = NLMSG_DATA(m->hdr);
+
+        *family = ndm->ndm_family;
+
+        return 0;
+}
+
+int sd_rtnl_message_neigh_get_ifindex(sd_rtnl_message *m, int *index) {
+        struct ndmsg *ndm;
+
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
+        assert_return(rtnl_message_type_is_neigh(m->hdr->nlmsg_type), -EINVAL);
+        assert_return(index, -EINVAL);
+
+        ndm = NLMSG_DATA(m->hdr);
+
+        *index = ndm->ndm_ifindex;
+
+        return 0;
+}
+
+int sd_rtnl_message_new_neigh(sd_rtnl *rtnl, sd_rtnl_message **ret, uint16_t nlmsg_type, int index, int ndm_family) {
+        struct ndmsg *ndm;
+        int r;
+
+        assert_return(rtnl_message_type_is_neigh(nlmsg_type), -EINVAL);
+        assert_return(ndm_family == AF_INET || ndm_family == AF_INET6, -EINVAL);
+        assert_return(ret, -EINVAL);
+
+        r = message_new(rtnl, ret, nlmsg_type);
+        if (r < 0)
+                return r;
+
+        if (nlmsg_type == RTM_NEWNEIGH)
+                (*ret)->hdr->nlmsg_flags |= NLM_F_CREATE | NLM_F_APPEND;
+
+        ndm = NLMSG_DATA((*ret)->hdr);
+
+        ndm->ndm_family = ndm_family;
+        ndm->ndm_ifindex = index;
+
+        return 0;
+}
+
 int sd_rtnl_message_link_set_flags(sd_rtnl_message *m, unsigned flags, unsigned change) {
         struct ifinfomsg *ifi;
 
@@ -184,6 +285,20 @@ int sd_rtnl_message_link_set_type(sd_rtnl_message *m, unsigned type) {
         return 0;
 }
 
+int sd_rtnl_message_link_set_family(sd_rtnl_message *m, unsigned family) {
+        struct ifinfomsg *ifi;
+
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
+        assert_return(rtnl_message_type_is_link(m->hdr->nlmsg_type), -EINVAL);
+
+        ifi = NLMSG_DATA(m->hdr);
+
+        ifi->ifi_family = family;
+
+        return 0;
+}
+
 int sd_rtnl_message_new_link(sd_rtnl *rtnl, sd_rtnl_message **ret,
                              uint16_t nlmsg_type, int index) {
         struct ifinfomsg *ifi;
@@ -211,9 +326,10 @@ int sd_rtnl_message_new_link(sd_rtnl *rtnl, sd_rtnl_message **ret,
 int sd_rtnl_message_request_dump(sd_rtnl_message *m, int dump) {
         assert_return(m, -EINVAL);
         assert_return(m->hdr, -EINVAL);
-        assert_return(m->hdr->nlmsg_type == RTM_GETLINK ||
-                      m->hdr->nlmsg_type == RTM_GETADDR ||
-                      m->hdr->nlmsg_type == RTM_GETROUTE,
+        assert_return(m->hdr->nlmsg_type == RTM_GETLINK  ||
+                      m->hdr->nlmsg_type == RTM_GETADDR  ||
+                      m->hdr->nlmsg_type == RTM_GETROUTE ||
+                      m->hdr->nlmsg_type == RTM_GETNEIGH,
                       -EINVAL);
 
         if (dump)
@@ -723,7 +839,7 @@ int sd_rtnl_message_open_container(sd_rtnl_message *m, unsigned short type) {
         if (r < 0)
                 return r;
 
-        r = add_rtattr(m, type, NULL, size);
+        r = add_rtattr(m, type | NLA_F_NESTED, NULL, size);
         if (r < 0)
                 return r;
 
@@ -799,6 +915,8 @@ int sd_rtnl_message_read_string(sd_rtnl_message *m, unsigned short type, const c
         int r;
         void *attr_data;
 
+        assert_return(m, -EINVAL);
+
         r = message_attribute_has_type(m, type, NLA_STRING);
         if (r < 0)
                 return r;
@@ -809,7 +927,8 @@ int sd_rtnl_message_read_string(sd_rtnl_message *m, unsigned short type, const c
         else if (strnlen(attr_data, r) >= (size_t) r)
                 return -EIO;
 
-        *data = (const char *) attr_data;
+        if (data)
+                *data = (const char *) attr_data;
 
         return 0;
 }
@@ -818,6 +937,8 @@ int sd_rtnl_message_read_u8(sd_rtnl_message *m, unsigned short type, uint8_t *da
         int r;
         void *attr_data;
 
+        assert_return(m, -EINVAL);
+
         r = message_attribute_has_type(m, type, NLA_U8);
         if (r < 0)
                 return r;
@@ -828,7 +949,8 @@ int sd_rtnl_message_read_u8(sd_rtnl_message *m, unsigned short type, uint8_t *da
         else if ((size_t) r < sizeof(uint8_t))
                 return -EIO;
 
-        *data = *(uint8_t *) attr_data;
+        if (data)
+                *data = *(uint8_t *) attr_data;
 
         return 0;
 }
@@ -837,6 +959,8 @@ int sd_rtnl_message_read_u16(sd_rtnl_message *m, unsigned short type, uint16_t *
         int r;
         void *attr_data;
 
+        assert_return(m, -EINVAL);
+
         r = message_attribute_has_type(m, type, NLA_U16);
         if (r < 0)
                 return r;
@@ -847,7 +971,8 @@ int sd_rtnl_message_read_u16(sd_rtnl_message *m, unsigned short type, uint16_t *
         else if ((size_t) r < sizeof(uint16_t))
                 return -EIO;
 
-        *data = *(uint16_t *) attr_data;
+        if (data)
+                *data = *(uint16_t *) attr_data;
 
         return 0;
 }
@@ -856,6 +981,8 @@ int sd_rtnl_message_read_u32(sd_rtnl_message *m, unsigned short type, uint32_t *
         int r;
         void *attr_data;
 
+        assert_return(m, -EINVAL);
+
         r = message_attribute_has_type(m, type, NLA_U32);
         if (r < 0)
                 return r;
@@ -866,7 +993,8 @@ int sd_rtnl_message_read_u32(sd_rtnl_message *m, unsigned short type, uint32_t *
         else if ((size_t)r < sizeof(uint32_t))
                 return -EIO;
 
-        *data = *(uint32_t *) attr_data;
+        if (data)
+                *data = *(uint32_t *) attr_data;
 
         return 0;
 }
@@ -875,6 +1003,8 @@ int sd_rtnl_message_read_ether_addr(sd_rtnl_message *m, unsigned short type, str
         int r;
         void *attr_data;
 
+        assert_return(m, -EINVAL);
+
         r = message_attribute_has_type(m, type, NLA_ETHER_ADDR);
         if (r < 0)
                 return r;
@@ -885,7 +1015,8 @@ int sd_rtnl_message_read_ether_addr(sd_rtnl_message *m, unsigned short type, str
         else if ((size_t)r < sizeof(struct ether_addr))
                 return -EIO;
 
-        memcpy(data, attr_data, sizeof(struct ether_addr));
+        if (data)
+                memcpy(data, attr_data, sizeof(struct ether_addr));
 
         return 0;
 }
@@ -894,6 +1025,8 @@ int sd_rtnl_message_read_cache_info(sd_rtnl_message *m, unsigned short type, str
         int r;
         void *attr_data;
 
+        assert_return(m, -EINVAL);
+
         r = message_attribute_has_type(m, type, NLA_CACHE_INFO);
         if (r < 0)
                 return r;
@@ -904,7 +1037,8 @@ int sd_rtnl_message_read_cache_info(sd_rtnl_message *m, unsigned short type, str
         else if ((size_t)r < sizeof(struct ifa_cacheinfo))
                 return -EIO;
 
-        memcpy(info, attr_data, sizeof(struct ifa_cacheinfo));
+        if (info)
+                memcpy(info, attr_data, sizeof(struct ifa_cacheinfo));
 
         return 0;
 }
@@ -913,6 +1047,8 @@ int sd_rtnl_message_read_in_addr(sd_rtnl_message *m, unsigned short type, struct
         int r;
         void *attr_data;
 
+        assert_return(m, -EINVAL);
+
         r = message_attribute_has_type(m, type, NLA_IN_ADDR);
         if (r < 0)
                 return r;
@@ -923,7 +1059,8 @@ int sd_rtnl_message_read_in_addr(sd_rtnl_message *m, unsigned short type, struct
         else if ((size_t)r < sizeof(struct in_addr))
                 return -EIO;
 
-        memcpy(data, attr_data, sizeof(struct in_addr));
+        if (data)
+                memcpy(data, attr_data, sizeof(struct in_addr));
 
         return 0;
 }
@@ -932,6 +1069,8 @@ int sd_rtnl_message_read_in6_addr(sd_rtnl_message *m, unsigned short type, struc
         int r;
         void *attr_data;
 
+        assert_return(m, -EINVAL);
+
         r = message_attribute_has_type(m, type, NLA_IN_ADDR);
         if (r < 0)
                 return r;
@@ -942,7 +1081,8 @@ int sd_rtnl_message_read_in6_addr(sd_rtnl_message *m, unsigned short type, struc
         else if ((size_t)r < sizeof(struct in6_addr))
                 return -EIO;
 
-        memcpy(data, attr_data, sizeof(struct in6_addr));
+        if (data)
+                memcpy(data, attr_data, sizeof(struct in6_addr));
 
         return 0;
 }
@@ -1066,7 +1206,7 @@ int rtnl_message_parse(sd_rtnl_message *m,
         *rta_tb_size = max + 1;
 
         for (; RTA_OK(rta, rt_len); rta = RTA_NEXT(rta, rt_len)) {
-                type = rta->rta_type;
+                type = RTA_TYPE(rta);
 
                 /* if the kernel is newer than the headers we used
                    when building, we ignore out-of-range attributes
@@ -1251,8 +1391,10 @@ int socket_read_message(sd_rtnl *rtnl) {
                 }
 
                 /* check that the size matches the message type */
-                if (new_msg->nlmsg_len < NLMSG_LENGTH(nl_type->size))
+                if (new_msg->nlmsg_len < NLMSG_LENGTH(nl_type->size)) {
+                        log_debug("sd-rtnl: message larger than expected, dropping");
                         continue;
+                }
 
                 r = message_new_empty(rtnl, &m);
                 if (r < 0)