chiark / gitweb /
rtnl: simplify route_new()
[elogind.git] / src / libsystemd-rtnl / rtnl-message.c
index 85cf55a3cdcc2df8cad09e0d5445512078f82b89..f8f2bcd4a6f18a17fc64b32bcb250f42882f99f7 100644 (file)
@@ -36,6 +36,8 @@ struct sd_rtnl_message {
 
         struct nlmsghdr *hdr;
 
+        struct rtattr *current_container;
+
         struct rtattr *next_rta;
         size_t remaining_size;
 
@@ -68,16 +70,78 @@ static int message_new(sd_rtnl_message **ret, size_t initial_size) {
         return 0;
 }
 
+int message_new_synthetic_error(int error, uint32_t serial, sd_rtnl_message **ret) {
+        struct nlmsgerr *err;
+        int r;
+
+        assert(error <= 0);
+
+        r = message_new(ret, NLMSG_SPACE(sizeof(struct nlmsgerr)));
+        if (r < 0)
+                return r;
+
+        (*ret)->hdr->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr));
+        (*ret)->hdr->nlmsg_type = NLMSG_ERROR;
+        (*ret)->hdr->nlmsg_seq = serial;
+
+        err = NLMSG_DATA((*ret)->hdr);
+
+        err->error = error;
+
+        return 0;
+}
+
+bool message_type_is_route(uint16_t type) {
+        switch (type) {
+                case RTM_NEWROUTE:
+                case RTM_GETROUTE:
+                case RTM_DELROUTE:
+                        return true;
+                default:
+                        return false;
+        }
+}
+
+bool message_type_is_link(uint16_t type) {
+        switch (type) {
+                case RTM_NEWLINK:
+                case RTM_SETLINK:
+                case RTM_GETLINK:
+                case RTM_DELLINK:
+                        return true;
+                default:
+                        return false;
+        }
+}
+
+bool message_type_is_addr(uint16_t type) {
+        switch (type) {
+                case RTM_NEWADDR:
+                case RTM_GETADDR:
+                case RTM_DELADDR:
+                        return true;
+                default:
+                        return false;
+        }
+}
+
+int sd_rtnl_message_route_set_dst_prefixlen(sd_rtnl_message *m, unsigned char prefixlen) {
+        struct rtmsg *rtm;
+
+        rtm = NLMSG_DATA(m->hdr);
+
+        rtm->rtm_dst_len = prefixlen;
+
+        return 0;
+}
+
 int sd_rtnl_message_route_new(uint16_t nlmsg_type, unsigned char rtm_family,
-                              unsigned char rtm_dst_len, unsigned char rtm_src_len,
-                              unsigned char rtm_tos, unsigned char rtm_table,
-                              unsigned char rtm_scope, unsigned char rtm_protocol,
-                              unsigned char rtm_type, unsigned rtm_flags, sd_rtnl_message **ret) {
+                              sd_rtnl_message **ret) {
         struct rtmsg *rtm;
         int r;
 
-        assert_return(nlmsg_type == RTM_NEWROUTE || nlmsg_type == RTM_DELROUTE ||
-                      nlmsg_type == RTM_GETROUTE, -EINVAL);
+        assert_return(message_type_is_route(nlmsg_type), -EINVAL);
+        assert_return(rtm_family == AF_INET || rtm_family == AF_INET6, -EINVAL);
         assert_return(ret, -EINVAL);
 
         r = message_new(ret, NLMSG_SPACE(sizeof(struct rtmsg)));
@@ -92,24 +156,40 @@ int sd_rtnl_message_route_new(uint16_t nlmsg_type, unsigned char rtm_family,
         rtm = NLMSG_DATA((*ret)->hdr);
 
         rtm->rtm_family = rtm_family;
-        rtm->rtm_dst_len = rtm_dst_len;
-        rtm->rtm_src_len = rtm_src_len;
-        rtm->rtm_tos = rtm_tos;
-        rtm->rtm_table = rtm_table;
-        rtm->rtm_protocol = rtm_protocol;
-        rtm->rtm_scope = rtm_scope;
-        rtm->rtm_type = rtm_type;
-        rtm->rtm_flags = rtm_flags;
+        rtm->rtm_scope = RT_SCOPE_UNIVERSE;
+        rtm->rtm_type = RTN_UNICAST;
+        rtm->rtm_table = RT_TABLE_MAIN;
+        rtm->rtm_protocol = RTPROT_BOOT;
+
+        return 0;
+}
+
+int sd_rtnl_message_link_set_flags(sd_rtnl_message *m, unsigned flags) {
+        struct ifinfomsg *ifi;
+
+        ifi = NLMSG_DATA(m->hdr);
+
+        ifi->ifi_flags = flags;
+
+        return 0;
+}
+
+int sd_rtnl_message_link_set_type(sd_rtnl_message *m, unsigned type) {
+        struct ifinfomsg *ifi;
+
+        ifi = NLMSG_DATA(m->hdr);
+
+        ifi->ifi_type = type;
 
         return 0;
 }
 
-int sd_rtnl_message_link_new(uint16_t nlmsg_type, int index, unsigned int type, unsigned int flags, sd_rtnl_message **ret) {
+int sd_rtnl_message_link_new(uint16_t nlmsg_type, int index, sd_rtnl_message **ret) {
         struct ifinfomsg *ifi;
         int r;
 
-        assert_return(nlmsg_type == RTM_NEWLINK || nlmsg_type == RTM_DELLINK || nlmsg_type == RTM_GETLINK, -EINVAL);
-        assert_return(index > 0, -EINVAL);
+        assert_return(message_type_is_link(nlmsg_type), -EINVAL);
+        assert_return(nlmsg_type == RTM_NEWLINK || index > 0, -EINVAL);
         assert_return(ret, -EINVAL);
 
         r = message_new(ret, NLMSG_SPACE(sizeof(struct ifinfomsg)));
@@ -118,13 +198,13 @@ int sd_rtnl_message_link_new(uint16_t nlmsg_type, int index, unsigned int type,
 
         (*ret)->hdr->nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
         (*ret)->hdr->nlmsg_type = nlmsg_type;
+        if (nlmsg_type == RTM_NEWLINK)
+                (*ret)->hdr->nlmsg_flags |= NLM_F_CREATE;
 
         ifi = NLMSG_DATA((*ret)->hdr);
 
         ifi->ifi_family = AF_UNSPEC;
         ifi->ifi_index = index;
-        ifi->ifi_type = type;
-        ifi->ifi_flags = flags;
         ifi->ifi_change = 0xffffffff;
 
         return 0;
@@ -134,7 +214,7 @@ int sd_rtnl_message_addr_new(uint16_t nlmsg_type, int index, unsigned char famil
         struct ifaddrmsg *ifa;
         int r;
 
-        assert_return(nlmsg_type == RTM_NEWADDR || nlmsg_type == RTM_DELADDR || nlmsg_type == RTM_GETADDR, -EINVAL);
+        assert_return(message_type_is_addr(nlmsg_type), -EINVAL);
         assert_return(index > 0, -EINVAL);
         assert_return(ret, -EINVAL);
 
@@ -181,23 +261,52 @@ int sd_rtnl_message_get_type(sd_rtnl_message *m, uint16_t *type) {
         return 0;
 }
 
+int sd_rtnl_message_link_get_ifindex(sd_rtnl_message *m, int *ifindex) {
+        struct ifinfomsg *ifi;
+
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
+        assert_return(message_type_is_link(m->hdr->nlmsg_type), -EINVAL);
+        assert_return(ifindex, -EINVAL);
+
+        ifi = NLMSG_DATA(m->hdr);
+
+        *ifindex = ifi->ifi_index;
+
+        return 0;
+}
+
+int sd_rtnl_message_link_get_flags(sd_rtnl_message *m, unsigned *flags) {
+        struct ifinfomsg *ifi;
+
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
+        assert_return(message_type_is_link(m->hdr->nlmsg_type), -EINVAL);
+        assert_return(flags, -EINVAL);
+
+        ifi = NLMSG_DATA(m->hdr);
+
+        *flags = ifi->ifi_flags;
+
+        return 0;
+}
+
 /* If successful the updated message will be correctly aligned, if unsuccessful the old message is
    untouched */
 static int add_rtattr(sd_rtnl_message *m, unsigned short type, const void *data, size_t data_length) {
         uint32_t rta_length, message_length;
         struct nlmsghdr *new_hdr;
         struct rtattr *rta;
+        char *padding;
 
-        assert_return(m, -EINVAL);
-        assert_return(m->hdr, -EINVAL);
-        assert_return(NLMSG_ALIGN(m->hdr->nlmsg_len) == m->hdr->nlmsg_len, -EINVAL);
-        assert_return(data, -EINVAL);
-        assert_return(data_length > 0, -EINVAL);
+        assert(m);
+        assert(m->hdr);
+        assert(NLMSG_ALIGN(m->hdr->nlmsg_len) == m->hdr->nlmsg_len);
+        assert(!data || data_length > 0);
 
-        /* get the size of the new rta attribute (without padding at the end) */
+        /* get the size of the new rta attribute (with padding at the end) */
         rta_length = RTA_LENGTH(data_length);
-        /* get the new message size (with padding between the old message and the new attrib,
-         * but no padding after)
+        /* get the new message size (with padding at the end)
          */
         message_length = m->hdr->nlmsg_len + RTA_ALIGN(rta_length);
 
@@ -212,13 +321,28 @@ static int add_rtattr(sd_rtnl_message *m, unsigned short type, const void *data,
         /* update message size */
         m->hdr->nlmsg_len = message_length;
 
+        /* we are inside a container, extend it */
+        if (m->current_container)
+                m->current_container->rta_len = (unsigned char *) m->hdr +
+                                                m->hdr->nlmsg_len -
+                                                (unsigned char *) m->current_container;
+
         /* fill in the attribute */
         rta->rta_type = type;
         rta->rta_len = rta_length;
-        /* we don't deal with the case where the user lies about the type and gives us
-         * too little data (so don't do that)
-         */
-        memcpy(RTA_DATA(rta), data, data_length);
+        if (!data) {
+                /* this is a container, set pointer */
+                m->current_container = rta;
+        } else {
+                /* we don't deal with the case where the user lies about the type
+                 * and gives us too little data (so don't do that)
+                */
+                padding = mempcpy(RTA_DATA(rta), data, data_length);
+                /* make sure also the padding at the end of the message is initialized */
+                memset(padding, '\0', (unsigned char *) m->hdr +
+                                      m->hdr->nlmsg_len -
+                                      (unsigned char *) padding);
+        }
 
         return 0;
 }
@@ -233,16 +357,40 @@ int sd_rtnl_message_append(sd_rtnl_message *m, unsigned short type, const void *
 
         sd_rtnl_message_get_type(m, &rtm_type);
 
+        if (m->current_container) {
+                switch (rtm_type) {
+                        case RTM_NEWLINK:
+                        case RTM_SETLINK:
+                        case RTM_GETLINK:
+                        case RTM_DELLINK:
+                                switch (m->current_container->rta_type) {
+                                        case IFLA_LINKINFO:
+                                                switch (type) {
+                                                        case IFLA_INFO_KIND:
+                                                                return add_rtattr(m, type, data, strlen(data) + 1);
+                                                        default:
+                                                                return -ENOTSUP;
+                                                }
+                                        default:
+                                                return -ENOTSUP;
+                                }
+                        default:
+                                return -ENOTSUP;
+                }
+        }
+
         switch (rtm_type) {
                 case RTM_NEWLINK:
+                case RTM_SETLINK:
                 case RTM_DELLINK:
                 case RTM_GETLINK:
                         switch (type) {
                                 case IFLA_IFNAME:
+                                case IFLA_IFALIAS:
                                 case IFLA_QDISC:
                                         return add_rtattr(m, type, data, strlen(data) + 1);
+                                case IFLA_MASTER:
                                 case IFLA_MTU:
-                                        return add_rtattr(m, type, data, sizeof(uint32_t));
                                 case IFLA_LINK:
                                         return add_rtattr(m, type, data, sizeof(uint32_t));
                                 case IFLA_STATS:
@@ -304,13 +452,62 @@ int sd_rtnl_message_append(sd_rtnl_message *m, unsigned short type, const void *
         }
 }
 
-static int message_read(sd_rtnl_message *m, unsigned short *type, void **data) {
+int sd_rtnl_message_open_container(sd_rtnl_message *m, unsigned short type) {
+        uint16_t rtm_type;
+
         assert_return(m, -EINVAL);
-        assert_return(data, -EINVAL);
+        assert_return(!m->current_container, -EINVAL);
+
+        sd_rtnl_message_get_type(m, &rtm_type);
+
+        if (message_type_is_link(rtm_type)) {
+                if (type == IFLA_LINKINFO)
+                        return add_rtattr(m, type, NULL, 0);
+                else
+                        return -ENOTSUP;
+        } else
+                return -ENOTSUP;
+
+        return 0;
+}
+
+int sd_rtnl_message_close_container(sd_rtnl_message *m) {
+        assert_return(m, -EINVAL);
+        assert_return(m->current_container, -EINVAL);
+
+        m->current_container = NULL;
+
+        return 0;
+}
+
+static int message_read(sd_rtnl_message *m, unsigned short *type, void **data) {
+        uint16_t rtm_type;
+        int r;
+
+        assert(m);
+        assert(m->next_rta);
+        assert(type);
+        assert(data);
 
         if (!RTA_OK(m->next_rta, m->remaining_size))
                 return 0;
 
+        /* make sure we don't try to read a container
+         * TODO: add support for entering containers for reading */
+        r = sd_rtnl_message_get_type(m, &rtm_type);
+        if (r < 0)
+                return r;
+
+        switch (rtm_type) {
+                case RTM_NEWLINK:
+                case RTM_GETLINK:
+                case RTM_SETLINK:
+                case RTM_DELLINK:
+                        if (m->next_rta->rta_type == IFLA_LINKINFO) {
+                                return -EINVAL;
+                        }
+        }
+
         *data = RTA_DATA(m->next_rta);
         *type = m->next_rta->rta_type;
 
@@ -321,14 +518,18 @@ static int message_read(sd_rtnl_message *m, unsigned short *type, void **data) {
 
 int sd_rtnl_message_read(sd_rtnl_message *m, unsigned short *type, void **data) {
         uint16_t rtm_type;
+        int r;
 
         assert_return(m, -EINVAL);
         assert_return(data, -EINVAL);
 
-        sd_rtnl_message_get_type(m, &rtm_type);
+        r = sd_rtnl_message_get_type(m, &rtm_type);
+        if (r < 0)
+                return r;
 
         switch (rtm_type) {
                 case RTM_NEWLINK:
+                case RTM_SETLINK:
                 case RTM_DELLINK:
                 case RTM_GETLINK:
                         if (!m->next_rta) {
@@ -365,16 +566,18 @@ int sd_rtnl_message_read(sd_rtnl_message *m, unsigned short *type, void **data)
         return message_read(m, type, data);
 }
 
-int message_get_serial(sd_rtnl_message *m) {
+uint32_t message_get_serial(sd_rtnl_message *m) {
         assert(m);
+        assert(m->hdr);
 
         return m->hdr->nlmsg_seq;
 }
 
-int message_get_errno(sd_rtnl_message *m) {
+int sd_rtnl_message_get_errno(sd_rtnl_message *m) {
         struct nlmsgerr *err;
 
-        assert(m);
+        assert_return(m, -EINVAL);
+        assert_return(m->hdr, -EINVAL);
 
         if (m->hdr->nlmsg_type != NLMSG_ERROR)
                 return 0;
@@ -385,6 +588,10 @@ int message_get_errno(sd_rtnl_message *m) {
 }
 
 int message_seal(sd_rtnl *nl, sd_rtnl_message *m) {
+        assert(nl);
+        assert(m);
+        assert(m->hdr);
+
         if (m->sealed)
                 return -EPERM;
 
@@ -395,8 +602,8 @@ int message_seal(sd_rtnl *nl, sd_rtnl_message *m) {
 }
 
 static int message_receive_need(sd_rtnl *rtnl, size_t *need) {
-        assert_return(rtnl, -EINVAL);
-        assert_return(need, -EINVAL);
+        assert(rtnl);
+        assert(need);
 
         /* ioctl(rtnl->fd, FIONREAD, &need)
            Does not appear to work on netlink sockets. libnl uses
@@ -424,8 +631,9 @@ int socket_write_message(sd_rtnl *nl, sd_rtnl_message *m) {
         };
         ssize_t k;
 
-        assert_return(nl, -EINVAL);
-        assert_return(m, -EINVAL);
+        assert(nl);
+        assert(m);
+        assert(m->hdr);
 
         k = sendto(nl->fd, m->hdr, m->hdr->nlmsg_len,
                         0, &addr.sa, sizeof(addr));
@@ -451,8 +659,8 @@ int socket_read_message(sd_rtnl *nl, sd_rtnl_message **ret) {
         ssize_t k;
         size_t need;
 
-        assert_return(nl, -EINVAL);
-        assert_return(ret, -EINVAL);
+        assert(nl);
+        assert(ret);
 
         r = message_receive_need(nl, &need);
         if (r < 0)
@@ -478,8 +686,8 @@ int socket_read_message(sd_rtnl *nl, sd_rtnl_message **ret) {
         else if ((size_t) k < sizeof(struct nlmsghdr) ||
                         (size_t) k < m->hdr->nlmsg_len)
                 k = -EIO; /* too small (we do accept too big though) */
-        else if (m->hdr->nlmsg_pid != nl->sockaddr.nl.nl_pid)
-                k = 0; /* not for us */
+        else if (m->hdr->nlmsg_pid && m->hdr->nlmsg_pid != nl->sockaddr.nl.nl_pid)
+                k = 0; /* not broadcast and not for us */
 
         if (k > 0)
                 switch (m->hdr->nlmsg_type) {
@@ -489,6 +697,7 @@ int socket_read_message(sd_rtnl *nl, sd_rtnl_message **ret) {
                                         k = -EIO;
                                 break;
                         case RTM_NEWLINK:
+                        case RTM_SETLINK:
                         case RTM_DELLINK:
                         case RTM_GETLINK:
                                 if (m->hdr->nlmsg_len < NLMSG_LENGTH(sizeof(struct ifinfomsg)))
@@ -500,6 +709,12 @@ int socket_read_message(sd_rtnl *nl, sd_rtnl_message **ret) {
                                 if (m->hdr->nlmsg_len < NLMSG_LENGTH(sizeof(struct ifaddrmsg)))
                                         k = -EIO;
                                 break;
+                        case RTM_NEWROUTE:
+                        case RTM_DELROUTE:
+                        case RTM_GETROUTE:
+                                if (m->hdr->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtmsg)))
+                                        k = -EIO;
+                                break;
                         case NLMSG_NOOP:
                                 k = 0;
                                 break;