/* network device (interface) functions. * (C) 2023 by sysmocom - s.f.m.c. GmbH * Author: Pau Espin Pedrol * * All Rights Reserved * * SPDX-License-Identifier: GPL-2.0+ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * */ #include "config.h" /*! \addtogroup netdev * @{ * network device (interface) convenience functions * * \file netdev.c * * Example lifecycle use of the API: * * struct osmo_sockaddr_str osa_str = {}; * struct osmo_sockaddr osa = {}; * * // Allocate object: * struct osmo_netdev *netdev = osmo_netdev_alloc(parent_talloc_ctx, name); * OSMO_ASSERT(netdev); * * // Configure object (before registration): * rc = osmo_netdev_set_netns_name(netdev, "some_netns_name_or_null"); * rc = osmo_netdev_set_ifindex(netdev, if_nametoindex("eth0")); * * // Register object: * rc = osmo_netdev_register(netdev); * // The network interface is now being monitored and the network interface * // can be operated (see below) * * // Add a local IPv4 address: * rc = osmo_sockaddr_str_from_str2(&osa_str, "192.168.200.1"); * rc = osmo_sockaddr_str_to_sockaddr(&osa_str, &osa.u.sas); * rc = osmo_netdev_add_addr(netdev, &osa, 24); * * // Bring network interface up: * rc = osmo_netdev_ifupdown(netdev, true); * * // Add default route (0.0.0.0/0): * rc = osmo_sockaddr_str_from_str2(&osa_str, "0.0.0.0"); * rc = osmo_sockaddr_str_to_sockaddr(&osa_str, &osa.u.sas); * rc = osmo_netdev_add_route(netdev, &osa, 0, NULL); * * // Unregister (can be freed directly too): * rc = osmo_netdev_unregister(netdev); * // Free the object: * osmo_netdev_free(netdev); */ #if (!EMBEDDED) #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if ENABLE_LIBMNL #if defined(__linux__) #include #include #else #error "Unknown platform!" #endif #endif /* ENABLE_LIBMNL */ #include #include #include #include #include #include #include #if ENABLE_LIBMNL #include #endif #define IFINDEX_UNUSED 0 #define LOGNETDEV(netdev, lvl, fmt, args ...) \ LOGP(DLGLOBAL, lvl, "NETDEV(%s,if=%s/%u,ns=%s): " fmt, \ (netdev)->name, osmo_netdev_get_dev_name(netdev) ? : "", \ (netdev)->ifindex, (netdev)->netns_name ? : "", ## args) static struct llist_head g_netdev_netns_ctx_list = LLIST_HEAD_INIT(g_netdev_netns_ctx_list); static struct llist_head g_netdev_list = LLIST_HEAD_INIT(g_netdev_list); /* One per netns, shared by all osmo_netdev in a given netns: */ struct netdev_netns_ctx { struct llist_head entry; /* entry in g_netdev_netns_ctx_list */ unsigned int refcount; /* Number of osmo_netdev currently registered on this netns */ const char *netns_name; /* default netns has empty string "" (never NULL!) */ int netns_fd; /* FD to the netns with name "netns_name" above */ #if ENABLE_LIBMNL struct osmo_mnl *omnl; #endif }; static struct netdev_netns_ctx *netdev_netns_ctx_alloc(void *ctx, const char *netns_name) { struct netdev_netns_ctx *netns_ctx; OSMO_ASSERT(netns_name); netns_ctx = talloc_zero(ctx, struct netdev_netns_ctx); if (!netns_ctx) return NULL; netns_ctx->netns_name = talloc_strdup(netns_ctx, netns_name); netns_ctx->netns_fd = -1; llist_add_tail(&netns_ctx->entry, &g_netdev_netns_ctx_list); return netns_ctx; } static void netdev_netns_ctx_free(struct netdev_netns_ctx *netns_ctx) { if (!netns_ctx) return; llist_del(&netns_ctx->entry); #if ENABLE_LIBMNL if (netns_ctx->omnl) { osmo_mnl_destroy(netns_ctx->omnl); netns_ctx->omnl = NULL; } #endif if (netns_ctx->netns_fd != -1) { close(netns_ctx->netns_fd); netns_ctx->netns_fd = -1; } talloc_free(netns_ctx); } #if ENABLE_LIBMNL static int netdev_netns_ctx_mnl_cb(const struct nlmsghdr *nlh, void *data); #endif static int netdev_netns_ctx_init(struct netdev_netns_ctx *netns_ctx) { struct osmo_netns_switch_state switch_state; int rc; if (netns_ctx->netns_name[0] != '\0') { LOGP(DLGLOBAL, LOGL_INFO, "Prepare netns: Switch to netns '%s'\n", netns_ctx->netns_name); netns_ctx->netns_fd = osmo_netns_open_fd(netns_ctx->netns_name); if (netns_ctx->netns_fd < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "Prepare netns: Cannot switch to netns '%s': %s (%d)\n", netns_ctx->netns_name, strerror(errno), errno); return netns_ctx->netns_fd; } /* temporarily switch to specified namespace to create netlink socket */ rc = osmo_netns_switch_enter(netns_ctx->netns_fd, &switch_state); if (rc < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "Prepare netns: Cannot switch to netns '%s': %s (%d)\n", netns_ctx->netns_name, strerror(errno), errno); /* netns_ctx->netns_fd will be freed by future call to netdev_netns_ctx_free() */ return rc; } } #if ENABLE_LIBMNL netns_ctx->omnl = osmo_mnl_init(NULL, NETLINK_ROUTE, RTMGRP_LINK, netdev_netns_ctx_mnl_cb, netns_ctx); rc = (netns_ctx->omnl ? 0 : -EFAULT); #else rc = 0; #endif /* switch back to default namespace */ if (netns_ctx->netns_name[0] != '\0') { int rc2 = osmo_netns_switch_exit(&switch_state); if (rc2 < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "Prepare netns: Cannot switch back from netns '%s': %s\n", netns_ctx->netns_name, strerror(errno)); return rc2; } LOGP(DLGLOBAL, LOGL_INFO, "Prepare netns: Back from netns '%s'\n", netns_ctx->netns_name); } return rc; } static struct netdev_netns_ctx *netdev_netns_ctx_find_by_netns_name(const char *netns_name) { struct netdev_netns_ctx *netns_ctx; llist_for_each_entry(netns_ctx, &g_netdev_netns_ctx_list, entry) { if (strcmp(netns_ctx->netns_name, netns_name)) continue; return netns_ctx; } return NULL; } static struct netdev_netns_ctx *netdev_netns_ctx_get(const char *netns_name) { struct netdev_netns_ctx *netns_ctx; int rc; OSMO_ASSERT(netns_name); netns_ctx = netdev_netns_ctx_find_by_netns_name(netns_name); if (!netns_ctx) { netns_ctx = netdev_netns_ctx_alloc(NULL, netns_name); if (!netns_ctx) return NULL; rc = netdev_netns_ctx_init(netns_ctx); if (rc < 0) { netdev_netns_ctx_free(netns_ctx); return NULL; } } netns_ctx->refcount++; return netns_ctx; } static void netdev_netns_ctx_put(struct netdev_netns_ctx *netns_ctx) { OSMO_ASSERT(netns_ctx); netns_ctx->refcount--; if (netns_ctx->refcount == 0) netdev_netns_ctx_free(netns_ctx); } struct osmo_netdev { /* entry in g_netdev_list */ struct llist_head entry; /* Pointer to struct shared (refcounted) by all osmo_netdev in the same netns: */ struct netdev_netns_ctx *netns_ctx; /* Name used to identify the osmo_netdev */ char *name; /* ifindex of the network interface (address space is per netns) */ unsigned int ifindex; /* Network interface name. Can change over lifetime of the interface. */ char *dev_name; /* netns name where the netdev interface is created (NULL = default netns) */ char *netns_name; /* API user private data */ void *priv_data; /* Whether the netdev is in operation (managing the netdev interface) */ bool registered; /* Called by netdev each time a new up/down state change is detected. Can be NULL. */ osmo_netdev_ifupdown_ind_cb_t ifupdown_ind_cb; /* Called by netdev each time the registered network interface is renamed by the system. Can be NULL. */ osmo_netdev_dev_name_chg_cb_t dev_name_chg_cb; /* Called by netdev each time the configured MTU changes in registered network interface. Can be NULL. */ osmo_netdev_mtu_chg_cb_t mtu_chg_cb; /* Whether the netdev interface is UP */ bool if_up; /* Whether we know the interface updown state (aka if if_up holds information)*/ bool if_up_known; /* The netdev interface MTU size */ uint32_t if_mtu; /* Whether we know the interface MTU size (aka if if_mtu holds information)*/ bool if_mtu_known; }; #define NETDEV_NETNS_ENTER(netdev, switch_state, str_prefix) \ do { \ if ((netdev)->netns_name) { \ LOGNETDEV(netdev, LOGL_DEBUG, str_prefix ": Switch to netns '%s'\n", \ (netdev)->netns_name); \ int rc2 = osmo_netns_switch_enter((netdev)->netns_ctx->netns_fd, switch_state); \ if (rc2 < 0) { \ LOGNETDEV(netdev, LOGL_ERROR, str_prefix ": Cannot switch to netns '%s': %s (%d)\n", \ (netdev)->netns_name, strerror(errno), errno); \ return -EACCES; \ } \ } \ } while (0) #define NETDEV_NETNS_EXIT(netdev, switch_state, str_prefix) \ do { \ if ((netdev)->netns_name) { \ int rc2 = osmo_netns_switch_exit(switch_state); \ if (rc2 < 0) { \ LOGNETDEV(netdev, LOGL_ERROR, str_prefix ": Cannot switch back from netns '%s': %s\n", \ (netdev)->netns_name, strerror(errno)); \ return rc2; \ } \ LOGNETDEV(netdev, LOGL_DEBUG, str_prefix ": Back from netns '%s'\n", \ (netdev)->netns_name); \ } \ } while (0) #if ENABLE_LIBMNL /* validate the netlink attributes */ static int netdev_mnl_data_attr_cb(const struct nlattr *attr, void *data) { const struct nlattr **tb = data; int type = mnl_attr_get_type(attr); if (mnl_attr_type_valid(attr, IFLA_MAX) < 0) return MNL_CB_OK; switch (type) { case IFLA_ADDRESS: if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0) return MNL_CB_ERROR; break; case IFLA_MTU: if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) return MNL_CB_ERROR; break; case IFLA_IFNAME: if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0) return MNL_CB_ERROR; break; } tb[type] = attr; return MNL_CB_OK; } static void netdev_mnl_check_mtu_change(struct osmo_netdev *netdev, uint32_t mtu) { if (netdev->if_mtu_known && netdev->if_mtu == mtu) return; LOGNETDEV(netdev, LOGL_NOTICE, "MTU changed: %u\n", mtu); if (netdev->mtu_chg_cb) netdev->mtu_chg_cb(netdev, mtu); netdev->if_mtu_known = true; netdev->if_mtu = mtu; } static void netdev_mnl_check_link_state_change(struct osmo_netdev *netdev, bool if_up) { if (netdev->if_up_known && netdev->if_up == if_up) return; LOGNETDEV(netdev, LOGL_NOTICE, "Physical link state changed: %s\n", if_up ? "UP" : "DOWN"); if (netdev->ifupdown_ind_cb) netdev->ifupdown_ind_cb(netdev, if_up); netdev->if_up_known = true; netdev->if_up = if_up; } static int netdev_mnl_cb(struct osmo_netdev *netdev, struct ifinfomsg *ifm, struct nlattr **tb) { char ifnamebuf[IF_NAMESIZE]; const char *ifname = NULL; bool if_running; if (tb[IFLA_IFNAME]) { ifname = mnl_attr_get_str(tb[IFLA_IFNAME]); LOGNETDEV(netdev, LOGL_DEBUG, "%s(): ifname=%s\n", __func__, ifname); } else { /* Try harder to obtain the ifname. This code path should in * general not be triggered since usually IFLA_IFNAME is there */ struct osmo_netns_switch_state switch_state; NETDEV_NETNS_ENTER(netdev, &switch_state, "if_indextoname"); ifname = if_indextoname(ifm->ifi_index, ifnamebuf); NETDEV_NETNS_EXIT(netdev, &switch_state, "if_indextoname"); } if (ifname) { /* Update dev_name if it changed: */ if (strcmp(netdev->dev_name, ifname) != 0) { if (netdev->dev_name_chg_cb) netdev->dev_name_chg_cb(netdev, ifname); osmo_talloc_replace_string(netdev, &netdev->dev_name, ifname); } } if (tb[IFLA_MTU]) { uint32_t mtu = mnl_attr_get_u32(tb[IFLA_MTU]); LOGNETDEV(netdev, LOGL_DEBUG, "%s(): mtu=%u\n", __func__, mtu); netdev_mnl_check_mtu_change(netdev, mtu); } if (tb[IFLA_ADDRESS]) { uint8_t *hwaddr = mnl_attr_get_payload(tb[IFLA_ADDRESS]); uint16_t hwaddr_len = mnl_attr_get_payload_len(tb[IFLA_ADDRESS]); LOGNETDEV(netdev, LOGL_DEBUG, "%s(): hwaddress=%s\n", __func__, osmo_hexdump(hwaddr, hwaddr_len)); } if_running = !!(ifm->ifi_flags & IFF_RUNNING); LOGNETDEV(netdev, LOGL_DEBUG, "%s(): up=%u running=%u\n", __func__, !!(ifm->ifi_flags & IFF_UP), if_running); netdev_mnl_check_link_state_change(netdev, if_running); return MNL_CB_OK; } static int netdev_netns_ctx_mnl_cb(const struct nlmsghdr *nlh, void *data) { struct osmo_mnl *omnl = data; struct netdev_netns_ctx *netns_ctx = (struct netdev_netns_ctx *)omnl->priv; struct nlattr *tb[IFLA_MAX+1] = {}; struct ifinfomsg *ifm = mnl_nlmsg_get_payload(nlh); struct osmo_netdev *netdev; OSMO_ASSERT(omnl); OSMO_ASSERT(ifm); mnl_attr_parse(nlh, sizeof(*ifm), netdev_mnl_data_attr_cb, tb); LOGP(DLGLOBAL, LOGL_DEBUG, "%s(): index=%d type=%d flags=0x%x family=%d\n", __func__, ifm->ifi_index, ifm->ifi_type, ifm->ifi_flags, ifm->ifi_family); if (ifm->ifi_index == IFINDEX_UNUSED) return MNL_CB_ERROR; /* Find the netdev (if any) using key . * Different users of the API may have its own osmo_netdev object * tracking potentially same netif, hence we need to iterate the whole list * and dispatch to all matches: */ bool found_any = false; llist_for_each_entry(netdev, &g_netdev_list, entry) { if (!netdev->registered) continue; if (netdev->ifindex != ifm->ifi_index) continue; if (strcmp(netdev->netns_ctx->netns_name, netns_ctx->netns_name)) continue; found_any = true; netdev_mnl_cb(netdev, ifm, &tb[0]); } if (!found_any) { LOGP(DLGLOBAL, LOGL_DEBUG, "%s(): device with ifindex %u on netns %s not registered\n", __func__, ifm->ifi_index, netns_ctx->netns_name); } return MNL_CB_OK; } /* Trigger an initial dump of the iface to get link information */ static int netdev_mnl_request_initial_dump(struct osmo_mnl *omnl, unsigned int if_index) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh = mnl_nlmsg_put_header(buf); struct ifinfomsg *ifm; nlh->nlmsg_type = RTM_GETLINK; nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; nlh->nlmsg_seq = (uint32_t)time(NULL); ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm)); ifm->ifi_family = AF_UNSPEC; ifm->ifi_index = if_index; if (mnl_socket_sendto(omnl->mnls, nlh, nlh->nlmsg_len) < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "mnl_socket_sendto\n"); return -EIO; } return 0; } static int netdev_mnl_set_ifupdown(struct osmo_mnl *omnl, unsigned int if_index, const char *dev_name, bool up) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh = mnl_nlmsg_put_header(buf); struct ifinfomsg *ifm; unsigned int change = 0; unsigned int flags = 0; if (up) { change |= IFF_UP; flags |= IFF_UP; } else { change |= IFF_UP; flags &= ~IFF_UP; } nlh->nlmsg_type = RTM_NEWLINK; nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; nlh->nlmsg_seq = (uint32_t)time(NULL); ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm)); ifm->ifi_family = AF_UNSPEC; ifm->ifi_change = change; ifm->ifi_flags = flags; ifm->ifi_index = if_index; if (dev_name) mnl_attr_put_str(nlh, IFLA_IFNAME, dev_name); if (mnl_socket_sendto(omnl->mnls, nlh, nlh->nlmsg_len) < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "mnl_socket_sendto\n"); return -EIO; } return 0; } static int netdev_mnl_set_mtu(struct osmo_mnl *omnl, unsigned int if_index, const char *dev_name, uint32_t mtu) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh = mnl_nlmsg_put_header(buf); struct ifinfomsg *ifm; nlh->nlmsg_type = RTM_NEWLINK; nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; nlh->nlmsg_seq = (uint32_t)time(NULL); ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm)); ifm->ifi_family = AF_UNSPEC; ifm->ifi_change = 0; ifm->ifi_flags = 0; ifm->ifi_index = if_index; mnl_attr_put_u32(nlh, IFLA_MTU, mtu); if (mnl_socket_sendto(omnl->mnls, nlh, nlh->nlmsg_len) < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "mnl_socket_sendto\n"); return -EIO; } return 0; } static int netdev_mnl_add_addr(struct osmo_mnl *omnl, unsigned int if_index, const struct osmo_sockaddr *osa, uint8_t prefix) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh = mnl_nlmsg_put_header(buf); struct ifaddrmsg *ifm; nlh->nlmsg_type = RTM_NEWADDR; nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_ACK; nlh->nlmsg_seq = (uint32_t)time(NULL); ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm)); ifm->ifa_family = osa->u.sa.sa_family; ifm->ifa_prefixlen = prefix; ifm->ifa_flags = IFA_F_PERMANENT; ifm->ifa_scope = RT_SCOPE_UNIVERSE; ifm->ifa_index = if_index; /* * The exact meaning of IFA_LOCAL and IFA_ADDRESS depend * on the address family being used and the device type. * For broadcast devices (like the interfaces we use), * for IPv4 we specify both and they are used interchangeably. * For IPv6, only IFA_ADDRESS needs to be set. */ switch (osa->u.sa.sa_family) { case AF_INET: mnl_attr_put_u32(nlh, IFA_LOCAL, osa->u.sin.sin_addr.s_addr); mnl_attr_put_u32(nlh, IFA_ADDRESS, osa->u.sin.sin_addr.s_addr); break; case AF_INET6: mnl_attr_put(nlh, IFA_ADDRESS, sizeof(struct in6_addr), &osa->u.sin6.sin6_addr); break; default: return -EINVAL; } if (mnl_socket_sendto(omnl->mnls, nlh, nlh->nlmsg_len) < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "mnl_socket_sendto\n"); return -EIO; } return 0; } static int netdev_mnl_del_addr(struct osmo_mnl *omnl, unsigned int if_index, const struct osmo_sockaddr *osa, uint8_t prefix) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh = mnl_nlmsg_put_header(buf); struct ifaddrmsg *ifm; nlh->nlmsg_type = RTM_DELADDR; nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_ACK; nlh->nlmsg_seq = (uint32_t)time(NULL); ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm)); ifm->ifa_family = osa->u.sa.sa_family; ifm->ifa_prefixlen = prefix; ifm->ifa_flags = IFA_F_PERMANENT; ifm->ifa_scope = RT_SCOPE_UNIVERSE; ifm->ifa_index = if_index; /* * The exact meaning of IFA_LOCAL and IFA_ADDRESS depend * on the address family being used and the device type. * For broadcast devices (like the interfaces we use), * for IPv4 we specify both and they are used interchangeably. * For IPv6, only IFA_ADDRESS needs to be set. */ switch (osa->u.sa.sa_family) { case AF_INET: mnl_attr_put_u32(nlh, IFA_LOCAL, osa->u.sin.sin_addr.s_addr); mnl_attr_put_u32(nlh, IFA_ADDRESS, osa->u.sin.sin_addr.s_addr); break; case AF_INET6: mnl_attr_put(nlh, IFA_ADDRESS, sizeof(struct in6_addr), &osa->u.sin6.sin6_addr); break; default: return -EINVAL; } if (mnl_socket_sendto(omnl->mnls, nlh, nlh->nlmsg_len) < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "mnl_socket_sendto\n"); return -EIO; } return 0; } static int netdev_mnl_add_route(struct osmo_mnl *omnl, unsigned int if_index, const struct osmo_sockaddr *dst_osa, uint8_t dst_prefix, const struct osmo_sockaddr *gw_osa) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh = mnl_nlmsg_put_header(buf); struct rtmsg *rtm; nlh->nlmsg_type = RTM_NEWROUTE; nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_ACK; nlh->nlmsg_seq = (uint32_t)time(NULL); rtm = mnl_nlmsg_put_extra_header(nlh, sizeof(*rtm)); rtm->rtm_family = dst_osa->u.sa.sa_family; rtm->rtm_dst_len = dst_prefix; rtm->rtm_src_len = 0; rtm->rtm_tos = 0; rtm->rtm_protocol = RTPROT_STATIC; rtm->rtm_table = RT_TABLE_MAIN; rtm->rtm_type = RTN_UNICAST; rtm->rtm_scope = gw_osa ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK; rtm->rtm_flags = 0; switch (dst_osa->u.sa.sa_family) { case AF_INET: mnl_attr_put_u32(nlh, RTA_DST, dst_osa->u.sin.sin_addr.s_addr); break; case AF_INET6: mnl_attr_put(nlh, RTA_DST, sizeof(struct in6_addr), &dst_osa->u.sin6.sin6_addr); break; default: return -EINVAL; } mnl_attr_put_u32(nlh, RTA_OIF, if_index); if (gw_osa) { switch (gw_osa->u.sa.sa_family) { case AF_INET: mnl_attr_put_u32(nlh, RTA_GATEWAY, gw_osa->u.sin.sin_addr.s_addr); break; case AF_INET6: mnl_attr_put(nlh, RTA_GATEWAY, sizeof(struct in6_addr), &gw_osa->u.sin6.sin6_addr); break; default: return -EINVAL; } } if (mnl_socket_sendto(omnl->mnls, nlh, nlh->nlmsg_len) < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "mnl_socket_sendto\n"); return -EIO; } return 0; } #endif /* if ENABLE_LIBMNL */ /*! Allocate a new netdev object. * \param[in] ctx talloc context to use as a parent when allocating the netdev object * \param[in] name A name providen to identify the netdev object * \returns newly allocated netdev object on success; NULL on error */ struct osmo_netdev *osmo_netdev_alloc(void *ctx, const char *name) { struct osmo_netdev *netdev; netdev = talloc_zero(ctx, struct osmo_netdev); if (!netdev) return NULL; netdev->name = talloc_strdup(netdev, name); llist_add_tail(&netdev->entry, &g_netdev_list); return netdev; } /*! Free an allocated netdev object. * \param[in] netdev The netdev object to free */ void osmo_netdev_free(struct osmo_netdev *netdev) { if (!netdev) return; if (osmo_netdev_is_registered(netdev)) osmo_netdev_unregister(netdev); llist_del(&netdev->entry); talloc_free(netdev); } /*! Start managing the network device referenced by the netdev object. * \param[in] netdev The netdev object to open * \returns 0 on success; negative on error */ int osmo_netdev_register(struct osmo_netdev *netdev) { char ifnamebuf[IF_NAMESIZE]; struct osmo_netns_switch_state switch_state; int rc = 0; if (netdev->registered) return -EALREADY; netdev->netns_ctx = netdev_netns_ctx_get(netdev->netns_name ? : ""); if (!netdev->netns_ctx) return -EFAULT; NETDEV_NETNS_ENTER(netdev, &switch_state, "register"); if (!if_indextoname(netdev->ifindex, ifnamebuf)) { rc = -ENODEV; goto err_put_exit; } osmo_talloc_replace_string(netdev, &netdev->dev_name, ifnamebuf); #if ENABLE_LIBMNL rc = netdev_mnl_request_initial_dump(netdev->netns_ctx->omnl, netdev->ifindex); #endif NETDEV_NETNS_EXIT(netdev, &switch_state, "register"); netdev->registered = true; return rc; err_put_exit: NETDEV_NETNS_EXIT(netdev, &switch_state, "register"); netdev_netns_ctx_put(netdev->netns_ctx); return rc; } /*! Unregister the netdev object (stop managing /moniutoring the interface) * \param[in] netdev The netdev object to close * \returns 0 on success; negative on error */ int osmo_netdev_unregister(struct osmo_netdev *netdev) { if (!netdev->registered) return -EALREADY; netdev->if_up_known = false; netdev->if_mtu_known = false; netdev_netns_ctx_put(netdev->netns_ctx); netdev->registered = false; return 0; } /*! Retrieve whether the netdev object is in "registered" state. * \param[in] netdev The netdev object to check * \returns true if in state "registered"; false otherwise */ bool osmo_netdev_is_registered(struct osmo_netdev *netdev) { return netdev->registered; } /*! Set private user data pointer on the netdev object. * \param[in] netdev The netdev object where the field is set */ void osmo_netdev_set_priv_data(struct osmo_netdev *netdev, void *priv_data) { netdev->priv_data = priv_data; } /*! Get private user data pointer from the netdev object. * \param[in] netdev The netdev object from where to retrieve the field * \returns The current value of the priv_data field. */ void *osmo_netdev_get_priv_data(struct osmo_netdev *netdev) { return netdev->priv_data; } /*! Set ifupdown_ind_cb callback, called when the link status (UP/DOWN) changes. * \param[in] netdev The netdev object where the field is set * \param[in] ifupdown_ind_cb the user provided function to be called when the link status (UP/DOWN) changes */ void osmo_netdev_set_ifupdown_ind_cb(struct osmo_netdev *netdev, osmo_netdev_ifupdown_ind_cb_t ifupdown_ind_cb) { netdev->ifupdown_ind_cb = ifupdown_ind_cb; } /*! Set dev_name_chg_cb callback, called when a change in the network name is detected * \param[in] netdev The netdev object where the field is set * \param[in] dev_name_chg_cb the user provided function to be called when a the interface is renamed */ void osmo_netdev_set_dev_name_chg_cb(struct osmo_netdev *netdev, osmo_netdev_dev_name_chg_cb_t dev_name_chg_cb) { netdev->dev_name_chg_cb = dev_name_chg_cb; } /*! Set mtu_chg_cb callback, called when a change in the network name is detected * \param[in] netdev The netdev object where the field is set * \param[in] mtu_chg_cb the user provided function to be called when the configured MTU at the interface changes */ void osmo_netdev_set_mtu_chg_cb(struct osmo_netdev *netdev, osmo_netdev_mtu_chg_cb_t mtu_chg_cb) { netdev->mtu_chg_cb = mtu_chg_cb; } /*! Get name used to identify the netdev object. * \param[in] netdev The netdev object from where to retrieve the field * \returns The current value of the name used to identify the netdev object */ const char *osmo_netdev_get_name(const struct osmo_netdev *netdev) { return netdev->name; } /*! Set (specify) interface index identifying the network interface to manage * \param[in] netdev The netdev object where the field is set * \param[in] ifindex The interface index identifying the interface * \returns 0 on success; negative on error * * The ifindex, together with the netns_name (see * osmo_netdev_netns_name_set()), form together the key identifiers of a * network interface to manage. * This field is used during osmo_netdev_register() time, and hence must be set * before calling that API, and cannot be changed when the netdev object is in * "registered" state. */ int osmo_netdev_set_ifindex(struct osmo_netdev *netdev, unsigned int ifindex) { if (netdev->registered) return -EALREADY; netdev->ifindex = ifindex; return 0; } /*! Get interface index identifying the interface managed by netdev * \param[in] netdev The netdev object from where to retrieve the field * \returns The current value of the configured netdev interface ifindex to use (0 = unset) */ unsigned int osmo_netdev_get_ifindex(const struct osmo_netdev *netdev) { return netdev->ifindex; } /*! Set (specify) name of the network namespace where the network interface to manage is located * \param[in] netdev The netdev object where the field is set * \param[in] netns_name The network namespace where the network interface is located * \returns 0 on success; negative on error * * The netns_name, together with the ifindex (see * osmo_netdev_ifindex_set()), form together the key identifiers of a * network interface to manage. * This field is used during osmo_netdev_register() time, and hence must be set * before calling that API, and cannot be changed when the netdev object is in * "registered" state. * If left as NULL (default), the management will be done in the current network namespace. */ int osmo_netdev_set_netns_name(struct osmo_netdev *netdev, const char *netns_name) { if (netdev->registered) return -EALREADY; osmo_talloc_replace_string(netdev, &netdev->netns_name, netns_name); return 0; } /*! Get name of network namespace used when opening the netdev interface * \param[in] netdev The netdev object from where to retrieve the field * \returns The current value of the configured network namespace */ const char *osmo_netdev_get_netns_name(const struct osmo_netdev *netdev) { return netdev->netns_name; } /*! Get name used to name the network interface created by the netdev object * \param[in] netdev The netdev object from where to retrieve the field * \returns The interface name (or NULL if unknown) * * This information is retrieved internally once the netdev object enters the * "registered" state. Hence, when not registered NULL can be returned. */ const char *osmo_netdev_get_dev_name(const struct osmo_netdev *netdev) { return netdev->dev_name; } /*! Set the MTU of the network interface * \param[in] netdev The netdev object where the field is set * \param[in] mtu The MTU to be set on the network interface * \returns 0 on success; negative on error * */ int osmo_netdev_set_mtu(struct osmo_netdev *netdev, uint32_t mtu) { struct osmo_netns_switch_state switch_state; int rc; if (!netdev->registered) return -ENODEV; LOGNETDEV(netdev, LOGL_NOTICE, "Setting dev %s MTU %" PRIu32 "\n", netdev->dev_name, mtu); NETDEV_NETNS_ENTER(netdev, &switch_state, "set_mtu"); #if ENABLE_LIBMNL rc = netdev_mnl_set_mtu(netdev->netns_ctx->omnl, netdev->ifindex, netdev->dev_name, mtu); #else LOGNETDEV(netdev, LOGL_ERROR, "%s: NOT SUPPORTED. Build libosmocore with --enable-libmnl.\n", __func__); rc = -ENOTSUP; #endif NETDEV_NETNS_EXIT(netdev, &switch_state, "set_mtu"); return rc; } /*! Bring netdev interface UP or DOWN. * \param[in] netdev The netdev object managing the netdev interface * \param[in] ifupdown true to set the interface UP, false to set it DOWN * \returns 0 on succes; negative on error. */ int osmo_netdev_ifupdown(struct osmo_netdev *netdev, bool ifupdown) { struct osmo_netns_switch_state switch_state; int rc; if (!netdev->registered) return -ENODEV; LOGNETDEV(netdev, LOGL_NOTICE, "Bringing dev %s %s\n", netdev->dev_name, ifupdown ? "UP" : "DOWN"); NETDEV_NETNS_ENTER(netdev, &switch_state, "ifupdown"); #if ENABLE_LIBMNL rc = netdev_mnl_set_ifupdown(netdev->netns_ctx->omnl, netdev->ifindex, netdev->dev_name, ifupdown); #else LOGNETDEV(netdev, LOGL_ERROR, "%s: NOT SUPPORTED. Build libosmocore with --enable-libmnl.\n", __func__); rc = -ENOTSUP; #endif NETDEV_NETNS_EXIT(netdev, &switch_state, "ifupdown"); return rc; } /*! Add IP address to netdev interface * \param[in] netdev The netdev object managing the netdev interface * \param[in] addr The local address to set on the interface * \param[in] prefixlen The network prefix of addr * \returns 0 on succes; negative on error. */ int osmo_netdev_add_addr(struct osmo_netdev *netdev, const struct osmo_sockaddr *addr, uint8_t prefixlen) { struct osmo_netns_switch_state switch_state; char buf[INET6_ADDRSTRLEN]; int rc; if (!netdev->registered) return -ENODEV; LOGNETDEV(netdev, LOGL_NOTICE, "Adding address %s/%u to dev %s\n", osmo_sockaddr_ntop(&addr->u.sa, buf), prefixlen, netdev->dev_name); NETDEV_NETNS_ENTER(netdev, &switch_state, "Add address"); #if ENABLE_LIBMNL rc = netdev_mnl_add_addr(netdev->netns_ctx->omnl, netdev->ifindex, addr, prefixlen); #else LOGNETDEV(netdev, LOGL_ERROR, "%s: NOT SUPPORTED. Build libosmocore with --enable-libmnl.\n", __func__); rc = -ENOTSUP; #endif NETDEV_NETNS_EXIT(netdev, &switch_state, "Add address"); return rc; } /*! Remove IP address from netdev interface * \param[in] netdev The netdev object managing the netdev interface * \param[in] addr The local address to remove from the interface * \param[in] prefixlen The network prefix of addr * \returns 0 on succes; negative on error. */ int osmo_netdev_del_addr(struct osmo_netdev *netdev, const struct osmo_sockaddr *addr, uint8_t prefixlen) { struct osmo_netns_switch_state switch_state; char buf[INET6_ADDRSTRLEN]; int rc; if (!netdev->registered) return -ENODEV; LOGNETDEV(netdev, LOGL_NOTICE, "Deleting address %s/%u from dev %s\n", osmo_sockaddr_ntop(&addr->u.sa, buf), prefixlen, netdev->dev_name); NETDEV_NETNS_ENTER(netdev, &switch_state, "Delete address"); #if ENABLE_LIBMNL rc = netdev_mnl_del_addr(netdev->netns_ctx->omnl, netdev->ifindex, addr, prefixlen); #else LOGNETDEV(netdev, LOGL_ERROR, "%s: NOT SUPPORTED. Build libosmocore with --enable-libmnl.\n", __func__); rc = -ENOTSUP; #endif NETDEV_NETNS_EXIT(netdev, &switch_state, "Delete address"); return rc; } /*! Add IP route to netdev interface * \param[in] netdev The netdev object managing the netdev interface * \param[in] dst_addr The destination address of the route * \param[in] dst_prefixlen The network prefix of dst_addr * \param[in] gw_addr The gateway address. Optional, can be NULL. * \returns 0 on succes; negative on error. */ int osmo_netdev_add_route(struct osmo_netdev *netdev, const struct osmo_sockaddr *dst_addr, uint8_t dst_prefixlen, const struct osmo_sockaddr *gw_addr) { struct osmo_netns_switch_state switch_state; char buf_dst[INET6_ADDRSTRLEN]; char buf_gw[INET6_ADDRSTRLEN]; int rc; if (!netdev->registered) return -ENODEV; LOGNETDEV(netdev, LOGL_NOTICE, "Adding route %s/%u%s%s dev %s\n", osmo_sockaddr_ntop(&dst_addr->u.sa, buf_dst), dst_prefixlen, gw_addr ? " via " : "", gw_addr ? osmo_sockaddr_ntop(&gw_addr->u.sa, buf_gw) : "", netdev->dev_name); NETDEV_NETNS_ENTER(netdev, &switch_state, "Add route"); #if ENABLE_LIBMNL rc = netdev_mnl_add_route(netdev->netns_ctx->omnl, netdev->ifindex, dst_addr, dst_prefixlen, gw_addr); #else LOGNETDEV(netdev, LOGL_ERROR, "%s: NOT SUPPORTED. Build libosmocore with --enable-libmnl.\n", __func__); rc = -ENOTSUP; #endif NETDEV_NETNS_EXIT(netdev, &switch_state, "Add route"); return rc; } #endif /* (!EMBEDDED) */ /*! @} */