diff options
| -rw-r--r-- | drivers/net/gtp.c | 305 | ||||
| -rw-r--r-- | include/uapi/linux/gtp.h | 1 |
2 files changed, 269 insertions, 37 deletions
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c index bf434d79f868..756714d4ad92 100644 --- a/drivers/net/gtp.c +++ b/drivers/net/gtp.c @@ -79,6 +79,12 @@ struct gtp_dev { u8 restart_count; }; +struct echo_info { + struct in_addr ms_addr_ip4; + struct in_addr peer_addr_ip4; + u8 gtp_version; +}; + static unsigned int gtp_net_id __read_mostly; struct gtp_net { @@ -87,6 +93,16 @@ struct gtp_net { static u32 gtp_h_initval; +static struct genl_family gtp_genl_family; + +enum gtp_multicast_groups { + GTP_GENL_MCGRP, +}; + +static const struct genl_multicast_group gtp_genl_mcgrps[] = { + [GTP_GENL_MCGRP] = { .name = GTP_GENL_MCGRP_NAME }, +}; + static void pdp_context_delete(struct pdp_ctx *pctx); static inline u32 gtp0_hashfn(u64 tid) @@ -243,12 +259,38 @@ static struct rtable *ip4_route_output_gtp(struct flowi4 *fl4, * by the receiver * Returns true if the echo req was correct, false otherwise. */ -static bool gtp0_validate_echo_req(struct gtp0_header *gtp0) +static bool gtp0_validate_echo_hdr(struct gtp0_header *gtp0) { return !(gtp0->tid || (gtp0->flags ^ 0x1e) || gtp0->number != 0xff || gtp0->flow); } +/* msg_type has to be GTP_ECHO_REQ or GTP_ECHO_RSP */ +static void gtp0_build_echo_msg(struct gtp0_header *hdr, __u8 msg_type) +{ + int len_pkt, len_hdr; + + hdr->flags = 0x1e; /* v0, GTP-non-prime. */ + hdr->type = msg_type; + /* GSM TS 09.60. 7.3 In all Path Management Flow Label and TID + * are not used and shall be set to 0. + */ + hdr->flow = 0; + hdr->tid = 0; + hdr->number = 0xff; + hdr->spare[0] = 0xff; + hdr->spare[1] = 0xff; + hdr->spare[2] = 0xff; + + len_pkt = sizeof(struct gtp0_packet); + len_hdr = sizeof(struct gtp0_header); + + if (msg_type == GTP_ECHO_RSP) + hdr->length = htons(len_pkt - len_hdr); + else + hdr->length = 0; +} + static int gtp0_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) { struct gtp0_packet *gtp_pkt; @@ -260,7 +302,7 @@ static int gtp0_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr)); - if (!gtp0_validate_echo_req(gtp0)) + if (!gtp0_validate_echo_hdr(gtp0)) return -1; seq = gtp0->seq; @@ -271,10 +313,7 @@ static int gtp0_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) gtp_pkt = skb_push(skb, sizeof(struct gtp0_packet)); memset(gtp_pkt, 0, sizeof(struct gtp0_packet)); - gtp_pkt->gtp0_h.flags = 0x1e; /* v0, GTP-non-prime. */ - gtp_pkt->gtp0_h.type = GTP_ECHO_RSP; - gtp_pkt->gtp0_h.length = - htons(sizeof(struct gtp0_packet) - sizeof(struct gtp0_header)); + gtp0_build_echo_msg(>p_pkt->gtp0_h, GTP_ECHO_RSP); /* GSM TS 09.60. 7.3 The Sequence Number in a signalling response * message shall be copied from the signalling request message @@ -282,16 +321,6 @@ static int gtp0_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) */ gtp_pkt->gtp0_h.seq = seq; - /* GSM TS 09.60. 7.3 In all Path Management Flow Label and TID - * are not used and shall be set to 0. - */ - gtp_pkt->gtp0_h.flow = 0; - gtp_pkt->gtp0_h.tid = 0; - gtp_pkt->gtp0_h.number = 0xff; - gtp_pkt->gtp0_h.spare[0] = 0xff; - gtp_pkt->gtp0_h.spare[1] = 0xff; - gtp_pkt->gtp0_h.spare[2] = 0xff; - gtp_pkt->ie.tag = GTPIE_RECOVERY; gtp_pkt->ie.val = gtp->restart_count; @@ -319,6 +348,61 @@ static int gtp0_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) return 0; } +static int gtp_genl_fill_echo(struct sk_buff *skb, u32 snd_portid, u32 snd_seq, + int flags, u32 type, struct echo_info echo) +{ + void *genlh; + + genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, flags, + type); + if (!genlh) + goto failure; + + if (nla_put_u32(skb, GTPA_VERSION, echo.gtp_version) || + nla_put_be32(skb, GTPA_PEER_ADDRESS, echo.peer_addr_ip4.s_addr) || + nla_put_be32(skb, GTPA_MS_ADDRESS, echo.ms_addr_ip4.s_addr)) + goto failure; + + genlmsg_end(skb, genlh); + return 0; + +failure: + genlmsg_cancel(skb, genlh); + return -EMSGSIZE; +} + +static int gtp0_handle_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) +{ + struct gtp0_header *gtp0; + struct echo_info echo; + struct sk_buff *msg; + struct iphdr *iph; + int ret; + + gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr)); + + if (!gtp0_validate_echo_hdr(gtp0)) + return -1; + + iph = ip_hdr(skb); + echo.ms_addr_ip4.s_addr = iph->daddr; + echo.peer_addr_ip4.s_addr = iph->saddr; + echo.gtp_version = GTP_V0; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); + if (!msg) + return -ENOMEM; + + ret = gtp_genl_fill_echo(msg, 0, 0, 0, GTP_CMD_ECHOREQ, echo); + if (ret < 0) { + nlmsg_free(msg); + return ret; + } + + return genlmsg_multicast_netns(>p_genl_family, dev_net(gtp->dev), + msg, 0, GTP_GENL_MCGRP, GFP_ATOMIC); +} + /* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */ static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb) { @@ -342,6 +426,9 @@ static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb) if (gtp0->type == GTP_ECHO_REQ && gtp->sk_created) return gtp0_send_echo_resp(gtp, skb); + if (gtp0->type == GTP_ECHO_RSP && gtp->sk_created) + return gtp0_handle_echo_resp(gtp, skb); + if (gtp0->type != GTP_TPDU) return 1; @@ -354,6 +441,36 @@ static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb) return gtp_rx(pctx, skb, hdrlen, gtp->role); } +/* msg_type has to be GTP_ECHO_REQ or GTP_ECHO_RSP */ +static void gtp1u_build_echo_msg(struct gtp1_header_long *hdr, __u8 msg_type) +{ + int len_pkt, len_hdr; + + /* S flag must be set to 1 */ + hdr->flags = 0x32; /* v1, GTP-non-prime. */ + hdr->type = msg_type; + /* 3GPP TS 29.281 5.1 - TEID has to be set to 0 */ + hdr->tid = 0; + + /* seq, npdu and next should be counted to the length of the GTP packet + * that's why szie of gtp1_header should be subtracted, + * not size of gtp1_header_long. + */ + + len_hdr = sizeof(struct gtp1_header); + + if (msg_type == GTP_ECHO_RSP) { + len_pkt = sizeof(struct gtp1u_packet); + hdr->length = htons(len_pkt - len_hdr); + } else { + /* GTP_ECHO_REQ does not carry GTP Information Element, + * the why gtp1_header_long is used here. + */ + len_pkt = sizeof(struct gtp1_header_long); + hdr->length = htons(len_pkt - len_hdr); + } +} + static int gtp1u_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) { struct gtp1_header_long *gtp1u; @@ -378,17 +495,7 @@ static int gtp1u_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) gtp_pkt = skb_push(skb, sizeof(struct gtp1u_packet)); memset(gtp_pkt, 0, sizeof(struct gtp1u_packet)); - /* S flag must be set to 1 */ - gtp_pkt->gtp1u_h.flags = 0x32; - gtp_pkt->gtp1u_h.type = GTP_ECHO_RSP; - /* seq, npdu and next should be counted to the length of the GTP packet - * that's why szie of gtp1_header should be subtracted, - * not why szie of gtp1_header_long. - */ - gtp_pkt->gtp1u_h.length = - htons(sizeof(struct gtp1u_packet) - sizeof(struct gtp1_header)); - /* 3GPP TS 29.281 5.1 - TEID has to be set to 0 */ - gtp_pkt->gtp1u_h.tid = 0; + gtp1u_build_echo_msg(>p_pkt->gtp1u_h, GTP_ECHO_RSP); /* 3GPP TS 29.281 7.7.2 - The Restart Counter value in the * Recovery information element shall not be used, i.e. it shall @@ -423,6 +530,42 @@ static int gtp1u_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) return 0; } +static int gtp1u_handle_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb) +{ + struct gtp1_header_long *gtp1u; + struct echo_info echo; + struct sk_buff *msg; + struct iphdr *iph; + int ret; + + gtp1u = (struct gtp1_header_long *)(skb->data + sizeof(struct udphdr)); + + /* 3GPP TS 29.281 5.1 - For the Echo Request, Echo Response, + * Error Indication and Supported Extension Headers Notification + * messages, the S flag shall be set to 1 and TEID shall be set to 0. + */ + if (!(gtp1u->flags & GTP1_F_SEQ) || gtp1u->tid) + return -1; + + iph = ip_hdr(skb); + echo.ms_addr_ip4.s_addr = iph->daddr; + echo.peer_addr_ip4.s_addr = iph->saddr; + echo.gtp_version = GTP_V1; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); + if (!msg) + return -ENOMEM; + + ret = gtp_genl_fill_echo(msg, 0, 0, 0, GTP_CMD_ECHOREQ, echo); + if (ret < 0) { + nlmsg_free(msg); + return ret; + } + + return genlmsg_multicast_netns(>p_genl_family, dev_net(gtp->dev), + msg, 0, GTP_GENL_MCGRP, GFP_ATOMIC); +} + static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb) { unsigned int hdrlen = sizeof(struct udphdr) + @@ -445,6 +588,9 @@ static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb) if (gtp1->type == GTP_ECHO_REQ && gtp->sk_created) return gtp1u_send_echo_resp(gtp, skb); + if (gtp1->type == GTP_ECHO_RSP && gtp->sk_created) + return gtp1u_handle_echo_resp(gtp, skb); + if (gtp1->type != GTP_TPDU) return 1; @@ -1431,16 +1577,6 @@ out_unlock: return err; } -static struct genl_family gtp_genl_family; - -enum gtp_multicast_groups { - GTP_GENL_MCGRP, -}; - -static const struct genl_multicast_group gtp_genl_mcgrps[] = { - [GTP_GENL_MCGRP] = { .name = GTP_GENL_MCGRP_NAME }, -}; - static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq, int flags, u32 type, struct pdp_ctx *pctx) { @@ -1584,6 +1720,95 @@ out: return skb->len; } +static int gtp_genl_send_echo_req(struct sk_buff *skb, struct genl_info *info) +{ + struct sk_buff *skb_to_send; + __be32 src_ip, dst_ip; + unsigned int version; + struct gtp_dev *gtp; + struct flowi4 fl4; + struct rtable *rt; + struct sock *sk; + __be16 port; + int len; + + if (!info->attrs[GTPA_VERSION] || + !info->attrs[GTPA_LINK] || + !info->attrs[GTPA_PEER_ADDRESS] || + !info->attrs[GTPA_MS_ADDRESS]) + return -EINVAL; + + version = nla_get_u32(info->attrs[GTPA_VERSION]); + dst_ip = nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]); + src_ip = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]); + + gtp = gtp_find_dev(sock_net(skb->sk), info->attrs); + if (!gtp) + return -ENODEV; + + if (!gtp->sk_created) + return -EOPNOTSUPP; + if (!(gtp->dev->flags & IFF_UP)) + return -ENETDOWN; + + if (version == GTP_V0) { + struct gtp0_header *gtp0_h; + + len = LL_RESERVED_SPACE(gtp->dev) + sizeof(struct gtp0_header) + + sizeof(struct iphdr) + sizeof(struct udphdr); + + skb_to_send = netdev_alloc_skb_ip_align(gtp->dev, len); + if (!skb_to_send) + return -ENOMEM; + + sk = gtp->sk0; + port = htons(GTP0_PORT); + + gtp0_h = skb_push(skb_to_send, sizeof(struct gtp0_header)); + memset(gtp0_h, 0, sizeof(struct gtp0_header)); + gtp0_build_echo_msg(gtp0_h, GTP_ECHO_REQ); + } else if (version == GTP_V1) { + struct gtp1_header_long *gtp1u_h; + + len = LL_RESERVED_SPACE(gtp->dev) + + sizeof(struct gtp1_header_long) + + sizeof(struct iphdr) + sizeof(struct udphdr); + + skb_to_send = netdev_alloc_skb_ip_align(gtp->dev, len); + if (!skb_to_send) + return -ENOMEM; + + sk = gtp->sk1u; + port = htons(GTP1U_PORT); + + gtp1u_h = skb_push(skb_to_send, + sizeof(struct gtp1_header_long)); + memset(gtp1u_h, 0, sizeof(struct gtp1_header_long)); + gtp1u_build_echo_msg(gtp1u_h, GTP_ECHO_REQ); + } else { + return -ENODEV; + } + + rt = ip4_route_output_gtp(&fl4, sk, dst_ip, src_ip); + if (IS_ERR(rt)) { + netdev_dbg(gtp->dev, "no route for echo request to %pI4\n", + &dst_ip); + kfree_skb(skb_to_send); + return -ENODEV; + } + + udp_tunnel_xmit_skb(rt, sk, skb_to_send, + fl4.saddr, fl4.daddr, + fl4.flowi4_tos, + ip4_dst_hoplimit(&rt->dst), + 0, + port, port, + !net_eq(sock_net(sk), + dev_net(gtp->dev)), + false); + return 0; +} + static const struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = { [GTPA_LINK] = { .type = NLA_U32, }, [GTPA_VERSION] = { .type = NLA_U32, }, @@ -1616,6 +1841,12 @@ static const struct genl_small_ops gtp_genl_ops[] = { .dumpit = gtp_genl_dump_pdp, .flags = GENL_ADMIN_PERM, }, + { + .cmd = GTP_CMD_ECHOREQ, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = gtp_genl_send_echo_req, + .flags = GENL_ADMIN_PERM, + }, }; static struct genl_family gtp_genl_family __ro_after_init = { diff --git a/include/uapi/linux/gtp.h b/include/uapi/linux/gtp.h index 79f9191bbb24..2f61298a7b77 100644 --- a/include/uapi/linux/gtp.h +++ b/include/uapi/linux/gtp.h @@ -8,6 +8,7 @@ enum gtp_genl_cmds { GTP_CMD_NEWPDP, GTP_CMD_DELPDP, GTP_CMD_GETPDP, + GTP_CMD_ECHOREQ, GTP_CMD_MAX, }; |