// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2010-2011 EIA Electronics, // Kurt Van Dijck // Copyright (c) 2018 Protonic, // Robin van der Gracht // Copyright (c) 2017-2019 Pengutronix, // Marc Kleine-Budde // Copyright (c) 2017-2019 Pengutronix, // Oleksij Rempel #include #include "j1939-priv.h" #define J1939_XTP_TX_RETRY_LIMIT 100 #define J1939_ETP_PGN_CTL 0xc800 #define J1939_ETP_PGN_DAT 0xc700 #define J1939_TP_PGN_CTL 0xec00 #define J1939_TP_PGN_DAT 0xeb00 #define J1939_TP_CMD_RTS 0x10 #define J1939_TP_CMD_CTS 0x11 #define J1939_TP_CMD_EOMA 0x13 #define J1939_TP_CMD_BAM 0x20 #define J1939_TP_CMD_ABORT 0xff #define J1939_ETP_CMD_RTS 0x14 #define J1939_ETP_CMD_CTS 0x15 #define J1939_ETP_CMD_DPO 0x16 #define J1939_ETP_CMD_EOMA 0x17 #define J1939_ETP_CMD_ABORT 0xff enum j1939_xtp_abort { J1939_XTP_NO_ABORT = 0, J1939_XTP_ABORT_BUSY = 1, /* Already in one or more connection managed sessions and * cannot support another. * * EALREADY: * Operation already in progress */ J1939_XTP_ABORT_RESOURCE = 2, /* System resources were needed for another task so this * connection managed session was terminated. * * EMSGSIZE: * The socket type requires that message be sent atomically, * and the size of the message to be sent made this * impossible. */ J1939_XTP_ABORT_TIMEOUT = 3, /* A timeout occurred and this is the connection abort to * close the session. * * EHOSTUNREACH: * The destination host cannot be reached (probably because * the host is down or a remote router cannot reach it). */ J1939_XTP_ABORT_GENERIC = 4, /* CTS messages received when data transfer is in progress * * EBADMSG: * Not a data message */ J1939_XTP_ABORT_FAULT = 5, /* Maximal retransmit request limit reached * * ENOTRECOVERABLE: * State not recoverable */ J1939_XTP_ABORT_UNEXPECTED_DATA = 6, /* Unexpected data transfer packet * * ENOTCONN: * Transport endpoint is not connected */ J1939_XTP_ABORT_BAD_SEQ = 7, /* Bad sequence number (and software is not able to recover) * * EILSEQ: * Illegal byte sequence */ J1939_XTP_ABORT_DUP_SEQ = 8, /* Duplicate sequence number (and software is not able to * recover) */ J1939_XTP_ABORT_EDPO_UNEXPECTED = 9, /* Unexpected EDPO packet (ETP) or Message size > 1785 bytes * (TP) */ J1939_XTP_ABORT_BAD_EDPO_PGN = 10, /* Unexpected EDPO PGN (PGN in EDPO is bad) */ J1939_XTP_ABORT_EDPO_OUTOF_CTS = 11, /* EDPO number of packets is greater than CTS */ J1939_XTP_ABORT_BAD_EDPO_OFFSET = 12, /* Bad EDPO offset */ J1939_XTP_ABORT_OTHER_DEPRECATED = 13, /* Deprecated. Use 250 instead (Any other reason) */ J1939_XTP_ABORT_ECTS_UNXPECTED_PGN = 14, /* Unexpected ECTS PGN (PGN in ECTS is bad) */ J1939_XTP_ABORT_ECTS_TOO_BIG = 15, /* ECTS requested packets exceeds message size */ J1939_XTP_ABORT_OTHER = 250, /* Any other reason (if a Connection Abort reason is * identified that is not listed in the table use code 250) */ }; static unsigned int j1939_tp_block = 255; static unsigned int j1939_tp_packet_delay; static unsigned int j1939_tp_padding = 1; /* helpers */ static const char *j1939_xtp_abort_to_str(enum j1939_xtp_abort abort) { switch (abort) { case J1939_XTP_ABORT_BUSY: return "Already in one or more connection managed sessions and cannot support another."; case J1939_XTP_ABORT_RESOURCE: return "System resources were needed for another task so this connection managed session was terminated."; case J1939_XTP_ABORT_TIMEOUT: return "A timeout occurred and this is the connection abort to close the session."; case J1939_XTP_ABORT_GENERIC: return "CTS messages received when data transfer is in progress"; case J1939_XTP_ABORT_FAULT: return "Maximal retransmit request limit reached"; case J1939_XTP_ABORT_UNEXPECTED_DATA: return "Unexpected data transfer packet"; case J1939_XTP_ABORT_BAD_SEQ: return "Bad sequence number (and software is not able to recover)"; case J1939_XTP_ABORT_DUP_SEQ: return "Duplicate sequence number (and software is not able to recover)"; case J1939_XTP_ABORT_EDPO_UNEXPECTED: return "Unexpected EDPO packet (ETP) or Message size > 1785 bytes (TP)"; case J1939_XTP_ABORT_BAD_EDPO_PGN: return "Unexpected EDPO PGN (PGN in EDPO is bad)"; case J1939_XTP_ABORT_EDPO_OUTOF_CTS: return "EDPO number of packets is greater than CTS"; case J1939_XTP_ABORT_BAD_EDPO_OFFSET: return "Bad EDPO offset"; case J1939_XTP_ABORT_OTHER_DEPRECATED: return "Deprecated. Use 250 instead (Any other reason)"; case J1939_XTP_ABORT_ECTS_UNXPECTED_PGN: return "Unexpected ECTS PGN (PGN in ECTS is bad)"; case J1939_XTP_ABORT_ECTS_TOO_BIG: return "ECTS requested packets exceeds message size"; case J1939_XTP_ABORT_OTHER: return "Any other reason (if a Connection Abort reason is identified that is not listed in the table use code 250)"; default: return ""; } } static int j1939_xtp_abort_to_errno(struct j1939_priv *priv, enum j1939_xtp_abort abort) { int err; switch (abort) { case J1939_XTP_NO_ABORT: WARN_ON_ONCE(abort == J1939_XTP_NO_ABORT); err = 0; break; case J1939_XTP_ABORT_BUSY: err = EALREADY; break; case J1939_XTP_ABORT_RESOURCE: err = EMSGSIZE; break; case J1939_XTP_ABORT_TIMEOUT: err = EHOSTUNREACH; break; case J1939_XTP_ABORT_GENERIC: err = EBADMSG; break; case J1939_XTP_ABORT_FAULT: err = ENOTRECOVERABLE; break; case J1939_XTP_ABORT_UNEXPECTED_DATA: err = ENOTCONN; break; case J1939_XTP_ABORT_BAD_SEQ: err = EILSEQ; break; case J1939_XTP_ABORT_DUP_SEQ: err = EPROTO; break; case J1939_XTP_ABORT_EDPO_UNEXPECTED: err = EPROTO; break; case J1939_XTP_ABORT_BAD_EDPO_PGN: err = EPROTO; break; case J1939_XTP_ABORT_EDPO_OUTOF_CTS: err = EPROTO; break; case J1939_XTP_ABORT_BAD_EDPO_OFFSET: err = EPROTO; break; case J1939_XTP_ABORT_OTHER_DEPRECATED: err = EPROTO; break; case J1939_XTP_ABORT_ECTS_UNXPECTED_PGN: err = EPROTO; break; case J1939_XTP_ABORT_ECTS_TOO_BIG: err = EPROTO; break; case J1939_XTP_ABORT_OTHER: err = EPROTO; break; default: netdev_warn(priv->ndev, "Unknown abort code %i", abort); err = EPROTO; } return err; } static inline void j1939_session_list_lock(struct j1939_priv *priv) { spin_lock_bh(&priv->active_session_list_lock); } static inline void j1939_session_list_unlock(struct j1939_priv *priv) { spin_unlock_bh(&priv->active_session_list_lock); } void j1939_session_get(struct j1939_session *session) { kref_get(&session->kref); } /* session completion functions */ static void __j1939_session_drop(struct j1939_session *session) { if (!session->transmission) return; j1939_sock_pending_del(session->sk); sock_put(session->sk); } static void j1939_session_destroy(struct j1939_session *session) { struct sk_buff *skb; if (session->transmission) { if (session->err) j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_ABORT); else j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_ACK); } else if (session->err) { j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); } netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); WARN_ON_ONCE(!list_empty(&session->sk_session_queue_entry)); WARN_ON_ONCE(!list_empty(&session->active_session_list_entry)); while ((skb = skb_dequeue(&session->skb_queue)) != NULL) { /* drop ref taken in j1939_session_skb_queue() */ skb_unref(skb); kfree_skb(skb); } __j1939_session_drop(session); j1939_priv_put(session->priv); kfree(session); } static void __j1939_session_release(struct kref *kref) { struct j1939_session *session = container_of(kref, struct j1939_session, kref); j1939_session_destroy(session); } void j1939_session_put(struct j1939_session *session) { kref_put(&session->kref, __j1939_session_release); } static void j1939_session_txtimer_cancel(struct j1939_session *session) { if (hrtimer_cancel(&session->txtimer)) j1939_session_put(session); } static void j1939_session_rxtimer_cancel(struct j1939_session *session) { if (hrtimer_cancel(&session->rxtimer)) j1939_session_put(session); } void j1939_session_timers_cancel(struct j1939_session *session) { j1939_session_txtimer_cancel(session); j1939_session_rxtimer_cancel(session); } static inline bool j1939_cb_is_broadcast(const struct j1939_sk_buff_cb *skcb) { return (!skcb->addr.dst_name && (skcb->addr.da == 0xff)); } static void j1939_session_skb_drop_old(struct j1939_session *session) { struct sk_buff *do_skb; struct j1939_sk_buff_cb *do_skcb; unsigned int offset_start; unsigned long flags; if (skb_queue_len(&session->skb_queue) < 2) return; offset_start = session->pkt.tx_acked * 7; spin_lock_irqsave(&session->skb_queue.lock, flags); do_skb = skb_peek(&session->skb_queue); do_skcb = j1939_skb_to_cb(do_skb); if ((do_skcb->offset + do_skb->len) < offset_start) { __skb_unlink(do_skb, &session->skb_queue); /* drop ref taken in j1939_session_skb_queue() */ skb_unref(do_skb); spin_unlock_irqrestore(&session->skb_queue.lock, flags); kfree_skb(do_skb); } else { spin_unlock_irqrestore(&session->skb_queue.lock, flags); } } void j1939_session_skb_queue(struct j1939_session *session, struct sk_buff *skb) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_priv *priv = session->priv; j1939_ac_fixup(priv, skb); if (j1939_address_is_unicast(skcb->addr.da) && priv->ents[skcb->addr.da].nusers) skcb->flags |= J1939_ECU_LOCAL_DST; skcb->flags |= J1939_ECU_LOCAL_SRC; skb_get(skb); skb_queue_tail(&session->skb_queue, skb); } static struct sk_buff *j1939_session_skb_get_by_offset(struct j1939_session *session, unsigned int offset_start) { struct j1939_priv *priv = session->priv; struct j1939_sk_buff_cb *do_skcb; struct sk_buff *skb = NULL; struct sk_buff *do_skb; unsigned long flags; spin_lock_irqsave(&session->skb_queue.lock, flags); skb_queue_walk(&session->skb_queue, do_skb) { do_skcb = j1939_skb_to_cb(do_skb); if (offset_start >= do_skcb->offset && offset_start < (do_skcb->offset + do_skb->len)) { skb = do_skb; } } if (skb) skb_get(skb); spin_unlock_irqrestore(&session->skb_queue.lock, flags); if (!skb) netdev_dbg(priv->ndev, "%s: 0x%p: no skb found for start: %i, queue size: %i\n", __func__, session, offset_start, skb_queue_len(&session->skb_queue)); return skb; } static struct sk_buff *j1939_session_skb_get(struct j1939_session *session) { unsigned int offset_start; offset_start = session->pkt.dpo * 7; return j1939_session_skb_get_by_offset(session, offset_start); } /* see if we are receiver * returns 0 for broadcasts, although we will receive them */ static inline int j1939_tp_im_receiver(const struct j1939_sk_buff_cb *skcb) { return skcb->flags & J1939_ECU_LOCAL_DST; } /* see if we are sender */ static inline int j1939_tp_im_transmitter(const struct j1939_sk_buff_cb *skcb) { return skcb->flags & J1939_ECU_LOCAL_SRC; } /* see if we are involved as either receiver or transmitter */ static int j1939_tp_im_involved(const struct j1939_sk_buff_cb *skcb, bool swap) { if (swap) return j1939_tp_im_receiver(skcb); else return j1939_tp_im_transmitter(skcb); } static int j1939_tp_im_involved_anydir(struct j1939_sk_buff_cb *skcb) { return skcb->flags & (J1939_ECU_LOCAL_SRC | J1939_ECU_LOCAL_DST); } /* extract pgn from flow-ctl message */ static inline pgn_t j1939_xtp_ctl_to_pgn(const u8 *dat) { pgn_t pgn; pgn = (dat[7] << 16) | (dat[6] << 8) | (dat[5] << 0); if (j1939_pgn_is_pdu1(pgn)) pgn &= 0xffff00; return pgn; } static inline unsigned int j1939_tp_ctl_to_size(const u8 *dat) { return (dat[2] << 8) + (dat[1] << 0); } static inline unsigned int j1939_etp_ctl_to_packet(const u8 *dat) { return (dat[4] << 16) | (dat[3] << 8) | (dat[2] << 0); } static inline unsigned int j1939_etp_ctl_to_size(const u8 *dat) { return (dat[4] << 24) | (dat[3] << 16) | (dat[2] << 8) | (dat[1] << 0); } /* find existing session: * reverse: swap cb's src & dst * there is no problem with matching broadcasts, since * broadcasts (no dst, no da) would never call this * with reverse == true */ static bool j1939_session_match(struct j1939_addr *se_addr, struct j1939_addr *sk_addr, bool reverse) { if (se_addr->type != sk_addr->type) return false; if (reverse) { if (se_addr->src_name) { if (se_addr->src_name != sk_addr->dst_name) return false; } else if (se_addr->sa != sk_addr->da) { return false; } if (se_addr->dst_name) { if (se_addr->dst_name != sk_addr->src_name) return false; } else if (se_addr->da != sk_addr->sa) { return false; } } else { if (se_addr->src_name) { if (se_addr->src_name != sk_addr->src_name) return false; } else if (se_addr->sa != sk_addr->sa) { return false; } if (se_addr->dst_name) { if (se_addr->dst_name != sk_addr->dst_name) return false; } else if (se_addr->da != sk_addr->da) { return false; } } return true; } static struct j1939_session *j1939_session_get_by_addr_locked(struct j1939_priv *priv, struct list_head *root, struct j1939_addr *addr, bool reverse, bool transmitter) { struct j1939_session *session; lockdep_assert_held(&priv->active_session_list_lock); list_for_each_entry(session, root, active_session_list_entry) { j1939_session_get(session); if (j1939_session_match(&session->skcb.addr, addr, reverse) && session->transmission == transmitter) return session; j1939_session_put(session); } return NULL; } static struct j1939_session *j1939_session_get_simple(struct j1939_priv *priv, struct sk_buff *skb) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_session *session; lockdep_assert_held(&priv->active_session_list_lock); list_for_each_entry(session, &priv->active_session_list, active_session_list_entry) { j1939_session_get(session); if (session->skcb.addr.type == J1939_SIMPLE && session->tskey == skcb->tskey && session->sk == skb->sk) return session; j1939_session_put(session); } return NULL; } static struct j1939_session *j1939_session_get_by_addr(struct j1939_priv *priv, struct j1939_addr *addr, bool reverse, bool transmitter) { struct j1939_session *session; j1939_session_list_lock(priv); session = j1939_session_get_by_addr_locked(priv, &priv->active_session_list, addr, reverse, transmitter); j1939_session_list_unlock(priv); return session; } static void j1939_skbcb_swap(struct j1939_sk_buff_cb *skcb) { u8 tmp = 0; swap(skcb->addr.dst_name, skcb->addr.src_name); swap(skcb->addr.da, skcb->addr.sa); /* swap SRC and DST flags, leave other untouched */ if (skcb->flags & J1939_ECU_LOCAL_SRC) tmp |= J1939_ECU_LOCAL_DST; if (skcb->flags & J1939_ECU_LOCAL_DST) tmp |= J1939_ECU_LOCAL_SRC; skcb->flags &= ~(J1939_ECU_LOCAL_SRC | J1939_ECU_LOCAL_DST); skcb->flags |= tmp; } static struct sk_buff *j1939_tp_tx_dat_new(struct j1939_priv *priv, const struct j1939_sk_buff_cb *re_skcb, bool ctl, bool swap_src_dst) { struct sk_buff *skb; struct j1939_sk_buff_cb *skcb; skb = alloc_skb(sizeof(struct can_frame) + sizeof(struct can_skb_priv), GFP_ATOMIC); if (unlikely(!skb)) return ERR_PTR(-ENOMEM); skb->dev = priv->ndev; can_skb_reserve(skb); can_skb_prv(skb)->ifindex = priv->ndev->ifindex; can_skb_prv(skb)->skbcnt = 0; /* reserve CAN header */ skb_reserve(skb, offsetof(struct can_frame, data)); /* skb->cb must be large enough to hold a j1939_sk_buff_cb structure */ BUILD_BUG_ON(sizeof(skb->cb) < sizeof(*re_skcb)); memcpy(skb->cb, re_skcb, sizeof(*re_skcb)); skcb = j1939_skb_to_cb(skb); if (swap_src_dst) j1939_skbcb_swap(skcb); if (ctl) { if (skcb->addr.type == J1939_ETP) skcb->addr.pgn = J1939_ETP_PGN_CTL; else skcb->addr.pgn = J1939_TP_PGN_CTL; } else { if (skcb->addr.type == J1939_ETP) skcb->addr.pgn = J1939_ETP_PGN_DAT; else skcb->addr.pgn = J1939_TP_PGN_DAT; } return skb; } /* TP transmit packet functions */ static int j1939_tp_tx_dat(struct j1939_session *session, const u8 *dat, int len) { struct j1939_priv *priv = session->priv; struct sk_buff *skb; skb = j1939_tp_tx_dat_new(priv, &session->skcb, false, false); if (IS_ERR(skb)) return PTR_ERR(skb); skb_put_data(skb, dat, len); if (j1939_tp_padding && len < 8) memset(skb_put(skb, 8 - len), 0xff, 8 - len); return j1939_send_one(priv, skb); } static int j1939_xtp_do_tx_ctl(struct j1939_priv *priv, const struct j1939_sk_buff_cb *re_skcb, bool swap_src_dst, pgn_t pgn, const u8 *dat) { struct sk_buff *skb; u8 *skdat; if (!j1939_tp_im_involved(re_skcb, swap_src_dst)) return 0; skb = j1939_tp_tx_dat_new(priv, re_skcb, true, swap_src_dst); if (IS_ERR(skb)) return PTR_ERR(skb); skdat = skb_put(skb, 8); memcpy(skdat, dat, 5); skdat[5] = (pgn >> 0); skdat[6] = (pgn >> 8); skdat[7] = (pgn >> 16); return j1939_send_one(priv, skb); } static inline int j1939_tp_tx_ctl(struct j1939_session *session, bool swap_src_dst, const u8 *dat) { struct j1939_priv *priv = session->priv; return j1939_xtp_do_tx_ctl(priv, &session->skcb, swap_src_dst, session->skcb.addr.pgn, dat); } static int j1939_xtp_tx_abort(struct j1939_priv *priv, const struct j1939_sk_buff_cb *re_skcb, bool swap_src_dst, enum j1939_xtp_abort err, pgn_t pgn) { u8 dat[5]; if (!j1939_tp_im_involved(re_skcb, swap_src_dst)) return 0; memset(dat, 0xff, sizeof(dat)); dat[0] = J1939_TP_CMD_ABORT; dat[1] = err; return j1939_xtp_do_tx_ctl(priv, re_skcb, swap_src_dst, pgn, dat); } void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec) { j1939_session_get(session); hrtimer_start(&session->txtimer, ms_to_ktime(msec), HRTIMER_MODE_REL_SOFT); } static inline void j1939_tp_set_rxtimeout(struct j1939_session *session, int msec) { j1939_session_rxtimer_cancel(session); j1939_session_get(session); hrtimer_start(&session->rxtimer, ms_to_ktime(msec), HRTIMER_MODE_REL_SOFT); } static int j1939_session_tx_rts(struct j1939_session *session) { u8 dat[8]; int ret; memset(dat, 0xff, sizeof(dat)); dat[1] = (session->total_message_size >> 0); dat[2] = (session->total_message_size >> 8); dat[3] = session->pkt.total; if (session->skcb.addr.type == J1939_ETP) { dat[0] = J1939_ETP_CMD_RTS; dat[1] = (session->total_message_size >> 0); dat[2] = (session->total_message_size >> 8); dat[3] = (session->total_message_size >> 16); dat[4] = (session->total_message_size >> 24); } else if (j1939_cb_is_broadcast(&session->skcb)) { dat[0] = J1939_TP_CMD_BAM; /* fake cts for broadcast */ session->pkt.tx = 0; } else { dat[0] = J1939_TP_CMD_RTS; dat[4] = dat[3]; } if (dat[0] == session->last_txcmd) /* done already */ return 0; ret = j1939_tp_tx_ctl(session, false, dat); if (ret < 0) return ret; session->last_txcmd = dat[0]; if (dat[0] == J1939_TP_CMD_BAM) { j1939_tp_schedule_txtimer(session, 50); j1939_tp_set_rxtimeout(session, 250); } else { j1939_tp_set_rxtimeout(session, 1250); } netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); return 0; } static int j1939_session_tx_dpo(struct j1939_session *session) { unsigned int pkt; u8 dat[8]; int ret; memset(dat, 0xff, sizeof(dat)); dat[0] = J1939_ETP_CMD_DPO; session->pkt.dpo = session->pkt.tx_acked; pkt = session->pkt.dpo; dat[1] = session->pkt.last - session->pkt.tx_acked; dat[2] = (pkt >> 0); dat[3] = (pkt >> 8); dat[4] = (pkt >> 16); ret = j1939_tp_tx_ctl(session, false, dat); if (ret < 0) return ret; session->last_txcmd = dat[0]; j1939_tp_set_rxtimeout(session, 1250); session->pkt.tx = session->pkt.tx_acked; netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); return 0; } static int j1939_session_tx_dat(struct j1939_session *session) { struct j1939_priv *priv = session->priv; struct j1939_sk_buff_cb *se_skcb; int offset, pkt_done, pkt_end; unsigned int len, pdelay; struct sk_buff *se_skb; const u8 *tpdat; int ret = 0; u8 dat[8]; se_skb = j1939_session_skb_get_by_offset(session, session->pkt.tx * 7); if (!se_skb) return -ENOBUFS; se_skcb = j1939_skb_to_cb(se_skb); tpdat = se_skb->data; ret = 0; pkt_done = 0; if (session->skcb.addr.type != J1939_ETP && j1939_cb_is_broadcast(&session->skcb)) pkt_end = session->pkt.total; else pkt_end = session->pkt.last; while (session->pkt.tx < pkt_end) { dat[0] = session->pkt.tx - session->pkt.dpo + 1; offset = (session->pkt.tx * 7) - se_skcb->offset; len = se_skb->len - offset; if (len > 7) len = 7; if (offset + len > se_skb->len) { netdev_err_once(priv->ndev, "%s: 0x%p: requested data outside of queued buffer: offset %i, len %i, pkt.tx: %i\n", __func__, session, se_skcb->offset, se_skb->len , session->pkt.tx); ret = -EOVERFLOW; goto out_free; } if (!len) { ret = -ENOBUFS; break; } memcpy(&dat[1], &tpdat[offset], len); ret = j1939_tp_tx_dat(session, dat, len + 1); if (ret < 0) { /* ENOBUFS == CAN interface TX queue is full */ if (ret != -ENOBUFS) netdev_alert(priv->ndev, "%s: 0x%p: queue data error: %i\n", __func__, session, ret); break; } session->last_txcmd = 0xff; pkt_done++; session->pkt.tx++; pdelay = j1939_cb_is_broadcast(&session->skcb) ? 50 : j1939_tp_packet_delay; if (session->pkt.tx < session->pkt.total && pdelay) { j1939_tp_schedule_txtimer(session, pdelay); break; } } if (pkt_done) j1939_tp_set_rxtimeout(session, 250); out_free: if (ret) kfree_skb(se_skb); else consume_skb(se_skb); return ret; } static int j1939_xtp_txnext_transmiter(struct j1939_session *session) { struct j1939_priv *priv = session->priv; int ret = 0; if (!j1939_tp_im_transmitter(&session->skcb)) { netdev_alert(priv->ndev, "%s: 0x%p: called by not transmitter!\n", __func__, session); return -EINVAL; } switch (session->last_cmd) { case 0: ret = j1939_session_tx_rts(session); break; case J1939_ETP_CMD_CTS: if (session->last_txcmd != J1939_ETP_CMD_DPO) { ret = j1939_session_tx_dpo(session); if (ret) return ret; } fallthrough; case J1939_TP_CMD_CTS: case 0xff: /* did some data */ case J1939_ETP_CMD_DPO: case J1939_TP_CMD_BAM: ret = j1939_session_tx_dat(session); break; default: netdev_alert(priv->ndev, "%s: 0x%p: unexpected last_cmd: %x\n", __func__, session, session->last_cmd); } return ret; } static int j1939_session_tx_cts(struct j1939_session *session) { struct j1939_priv *priv = session->priv; unsigned int pkt, len; int ret; u8 dat[8]; if (!j1939_sk_recv_match(priv, &session->skcb)) return -ENOENT; len = session->pkt.total - session->pkt.rx; len = min3(len, session->pkt.block, j1939_tp_block ?: 255); memset(dat, 0xff, sizeof(dat)); if (session->skcb.addr.type == J1939_ETP) { pkt = session->pkt.rx + 1; dat[0] = J1939_ETP_CMD_CTS; dat[1] = len; dat[2] = (pkt >> 0); dat[3] = (pkt >> 8); dat[4] = (pkt >> 16); } else { dat[0] = J1939_TP_CMD_CTS; dat[1] = len; dat[2] = session->pkt.rx + 1; } if (dat[0] == session->last_txcmd) /* done already */ return 0; ret = j1939_tp_tx_ctl(session, true, dat); if (ret < 0) return ret; if (len) /* only mark cts done when len is set */ session->last_txcmd = dat[0]; j1939_tp_set_rxtimeout(session, 1250); netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); return 0; } static int j1939_session_tx_eoma(struct j1939_session *session) { struct j1939_priv *priv = session->priv; u8 dat[8]; int ret; if (!j1939_sk_recv_match(priv, &session->skcb)) return -ENOENT; memset(dat, 0xff, sizeof(dat)); if (session->skcb.addr.type == J1939_ETP) { dat[0] = J1939_ETP_CMD_EOMA; dat[1] = session->total_message_size >> 0; dat[2] = session->total_message_size >> 8; dat[3] = session->total_message_size >> 16; dat[4] = session->total_message_size >> 24; } else { dat[0] = J1939_TP_CMD_EOMA; dat[1] = session->total_message_size; dat[2] = session->total_message_size >> 8; dat[3] = session->pkt.total; } if (dat[0] == session->last_txcmd) /* done already */ return 0; ret = j1939_tp_tx_ctl(session, true, dat); if (ret < 0) return ret; session->last_txcmd = dat[0]; /* wait for the EOMA packet to come in */ j1939_tp_set_rxtimeout(session, 1250); netdev_dbg(session->priv->ndev, "%p: 0x%p\n", __func__, session); return 0; } static int j1939_xtp_txnext_receiver(struct j1939_session *session) { struct j1939_priv *priv = session->priv; int ret = 0; if (!j1939_tp_im_receiver(&session->skcb)) { netdev_alert(priv->ndev, "%s: 0x%p: called by not receiver!\n", __func__, session); return -EINVAL; } switch (session->last_cmd) { case J1939_TP_CMD_RTS: case J1939_ETP_CMD_RTS: ret = j1939_session_tx_cts(session); break; case J1939_ETP_CMD_CTS: case J1939_TP_CMD_CTS: case 0xff: /* did some data */ case J1939_ETP_CMD_DPO: if ((session->skcb.addr.type == J1939_TP && j1939_cb_is_broadcast(&session->skcb))) break; if (session->pkt.rx >= session->pkt.total) { ret = j1939_session_tx_eoma(session); } else if (session->pkt.rx >= session->pkt.last) { session->last_txcmd = 0; ret = j1939_session_tx_cts(session); } break; default: netdev_alert(priv->ndev, "%s: 0x%p: unexpected last_cmd: %x\n", __func__, session, session->last_cmd); } return ret; } static int j1939_simple_txnext(struct j1939_session *session) { struct j1939_priv *priv = session->priv; struct sk_buff *se_skb = j1939_session_skb_get(session); struct sk_buff *skb; int ret; if (!se_skb) return 0; skb = skb_clone(se_skb, GFP_ATOMIC); if (!skb) { ret = -ENOMEM; goto out_free; } can_skb_set_owner(skb, se_skb->sk); j1939_tp_set_rxtimeout(session, J1939_SIMPLE_ECHO_TIMEOUT_MS); ret = j1939_send_one(priv, skb); if (ret) goto out_free; j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_SCHED); j1939_sk_queue_activate_next(session); out_free: if (ret) kfree_skb(se_skb); else consume_skb(se_skb); return ret; } static bool j1939_session_deactivate_locked(struct j1939_session *session) { bool active = false; lockdep_assert_held(&session->priv->active_session_list_lock); if (session->state >= J1939_SESSION_ACTIVE && session->state < J1939_SESSION_ACTIVE_MAX) { active = true; list_del_init(&session->active_session_list_entry); session->state = J1939_SESSION_DONE; j1939_session_put(session); } return active; } static bool j1939_session_deactivate(struct j1939_session *session) { struct j1939_priv *priv = session->priv; bool active; j1939_session_list_lock(priv); active = j1939_session_deactivate_locked(session); j1939_session_list_unlock(priv); return active; } static void j1939_session_deactivate_activate_next(struct j1939_session *session) { if (j1939_session_deactivate(session)) j1939_sk_queue_activate_next(session); } static void __j1939_session_cancel(struct j1939_session *session, enum j1939_xtp_abort err) { struct j1939_priv *priv = session->priv; WARN_ON_ONCE(!err); lockdep_assert_held(&session->priv->active_session_list_lock); session->err = j1939_xtp_abort_to_errno(priv, err); session->state = J1939_SESSION_WAITING_ABORT; /* do not send aborts on incoming broadcasts */ if (!j1939_cb_is_broadcast(&session->skcb)) { j1939_xtp_tx_abort(priv, &session->skcb, !session->transmission, err, session->skcb.addr.pgn); } if (session->sk) j1939_sk_send_loop_abort(session->sk, session->err); } static void j1939_session_cancel(struct j1939_session *session, enum j1939_xtp_abort err) { j1939_session_list_lock(session->priv); if (session->state >= J1939_SESSION_ACTIVE && session->state < J1939_SESSION_WAITING_ABORT) { j1939_tp_set_rxtimeout(session, J1939_XTP_ABORT_TIMEOUT_MS); __j1939_session_cancel(session, err); } j1939_session_list_unlock(session->priv); if (!session->sk) j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); } static enum hrtimer_restart j1939_tp_txtimer(struct hrtimer *hrtimer) { struct j1939_session *session = container_of(hrtimer, struct j1939_session, txtimer); struct j1939_priv *priv = session->priv; int ret = 0; if (session->skcb.addr.type == J1939_SIMPLE) { ret = j1939_simple_txnext(session); } else { if (session->transmission) ret = j1939_xtp_txnext_transmiter(session); else ret = j1939_xtp_txnext_receiver(session); } switch (ret) { case -ENOBUFS: /* Retry limit is currently arbitrary chosen */ if (session->tx_retry < J1939_XTP_TX_RETRY_LIMIT) { session->tx_retry++; j1939_tp_schedule_txtimer(session, 10 + prandom_u32_max(16)); } else { netdev_alert(priv->ndev, "%s: 0x%p: tx retry count reached\n", __func__, session); session->err = -ENETUNREACH; j1939_session_rxtimer_cancel(session); j1939_session_deactivate_activate_next(session); } break; case -ENETDOWN: /* In this case we should get a netdev_event(), all active * sessions will be cleared by * j1939_cancel_all_active_sessions(). So handle this as an * error, but let j1939_cancel_all_active_sessions() do the * cleanup including propagation of the error to user space. */ break; case -EOVERFLOW: j1939_session_cancel(session, J1939_XTP_ABORT_ECTS_TOO_BIG); break; case 0: session->tx_retry = 0; break; default: netdev_alert(priv->ndev, "%s: 0x%p: tx aborted with unknown reason: %i\n", __func__, session, ret); if (session->skcb.addr.type != J1939_SIMPLE) { j1939_session_cancel(session, J1939_XTP_ABORT_OTHER); } else { session->err = ret; j1939_session_rxtimer_cancel(session); j1939_session_deactivate_activate_next(session); } } j1939_session_put(session); return HRTIMER_NORESTART; } static void j1939_session_completed(struct j1939_session *session) { struct sk_buff *se_skb; if (!session->transmission) { se_skb = j1939_session_skb_get(session); /* distribute among j1939 receivers */ j1939_sk_recv(session->priv, se_skb); consume_skb(se_skb); } j1939_session_deactivate_activate_next(session); } static enum hrtimer_restart j1939_tp_rxtimer(struct hrtimer *hrtimer) { struct j1939_session *session = container_of(hrtimer, struct j1939_session, rxtimer); struct j1939_priv *priv = session->priv; if (session->state == J1939_SESSION_WAITING_ABORT) { netdev_alert(priv->ndev, "%s: 0x%p: abort rx timeout. Force session deactivation\n", __func__, session); j1939_session_deactivate_activate_next(session); } else if (session->skcb.addr.type == J1939_SIMPLE) { netdev_alert(priv->ndev, "%s: 0x%p: Timeout. Failed to send simple message.\n", __func__, session); /* The message is probably stuck in the CAN controller and can * be send as soon as CAN bus is in working state again. */ session->err = -ETIME; j1939_session_deactivate(session); } else { j1939_session_list_lock(session->priv); if (session->state >= J1939_SESSION_ACTIVE && session->state < J1939_SESSION_ACTIVE_MAX) { netdev_alert(priv->ndev, "%s: 0x%p: rx timeout, send abort\n", __func__, session); j1939_session_get(session); hrtimer_start(&session->rxtimer, ms_to_ktime(J1939_XTP_ABORT_TIMEOUT_MS), HRTIMER_MODE_REL_SOFT); __j1939_session_cancel(session, J1939_XTP_ABORT_TIMEOUT); } j1939_session_list_unlock(session->priv); if (!session->sk) j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); } j1939_session_put(session); return HRTIMER_NORESTART; } static bool j1939_xtp_rx_cmd_bad_pgn(struct j1939_session *session, const struct sk_buff *skb) { const struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); pgn_t pgn = j1939_xtp_ctl_to_pgn(skb->data); struct j1939_priv *priv = session->priv; enum j1939_xtp_abort abort = J1939_XTP_NO_ABORT; u8 cmd = skb->data[0]; if (session->skcb.addr.pgn == pgn) return false; switch (cmd) { case J1939_TP_CMD_BAM: abort = J1939_XTP_NO_ABORT; break; case J1939_ETP_CMD_RTS: fallthrough; case J1939_TP_CMD_RTS: abort = J1939_XTP_ABORT_BUSY; break; case J1939_ETP_CMD_CTS: fallthrough; case J1939_TP_CMD_CTS: abort = J1939_XTP_ABORT_ECTS_UNXPECTED_PGN; break; case J1939_ETP_CMD_DPO: abort = J1939_XTP_ABORT_BAD_EDPO_PGN; break; case J1939_ETP_CMD_EOMA: fallthrough; case J1939_TP_CMD_EOMA: abort = J1939_XTP_ABORT_OTHER; break; case J1939_ETP_CMD_ABORT: /* && J1939_TP_CMD_ABORT */ abort = J1939_XTP_NO_ABORT; break; default: WARN_ON_ONCE(1); break; } netdev_warn(priv->ndev, "%s: 0x%p: CMD 0x%02x with PGN 0x%05x for running session with different PGN 0x%05x.\n", __func__, session, cmd, pgn, session->skcb.addr.pgn); if (abort != J1939_XTP_NO_ABORT) j1939_xtp_tx_abort(priv, skcb, true, abort, pgn); return true; } static void j1939_xtp_rx_abort_one(struct j1939_priv *priv, struct sk_buff *skb, bool reverse, bool transmitter) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_session *session; u8 abort = skb->data[1]; session = j1939_session_get_by_addr(priv, &skcb->addr, reverse, transmitter); if (!session) return; if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) goto abort_put; netdev_info(priv->ndev, "%s: 0x%p: 0x%05x: (%u) %s\n", __func__, session, j1939_xtp_ctl_to_pgn(skb->data), abort, j1939_xtp_abort_to_str(abort)); j1939_session_timers_cancel(session); session->err = j1939_xtp_abort_to_errno(priv, abort); if (session->sk) j1939_sk_send_loop_abort(session->sk, session->err); else j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); j1939_session_deactivate_activate_next(session); abort_put: j1939_session_put(session); } /* abort packets may come in 2 directions */ static void j1939_xtp_rx_abort(struct j1939_priv *priv, struct sk_buff *skb, bool transmitter) { j1939_xtp_rx_abort_one(priv, skb, false, transmitter); j1939_xtp_rx_abort_one(priv, skb, true, transmitter); } static void j1939_xtp_rx_eoma_one(struct j1939_session *session, struct sk_buff *skb) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); const u8 *dat; int len; if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) return; dat = skb->data; if (skcb->addr.type == J1939_ETP) len = j1939_etp_ctl_to_size(dat); else len = j1939_tp_ctl_to_size(dat); if (session->total_message_size != len) { netdev_warn_once(session->priv->ndev, "%s: 0x%p: Incorrect size. Expected: %i; got: %i.\n", __func__, session, session->total_message_size, len); } netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); session->pkt.tx_acked = session->pkt.total; j1939_session_timers_cancel(session); /* transmitted without problems */ j1939_session_completed(session); } static void j1939_xtp_rx_eoma(struct j1939_priv *priv, struct sk_buff *skb, bool transmitter) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_session *session; session = j1939_session_get_by_addr(priv, &skcb->addr, true, transmitter); if (!session) return; j1939_xtp_rx_eoma_one(session, skb); j1939_session_put(session); } static void j1939_xtp_rx_cts_one(struct j1939_session *session, struct sk_buff *skb) { enum j1939_xtp_abort err = J1939_XTP_ABORT_FAULT; unsigned int pkt; const u8 *dat; dat = skb->data; if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) return; netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); if (session->last_cmd == dat[0]) { err = J1939_XTP_ABORT_DUP_SEQ; goto out_session_cancel; } if (session->skcb.addr.type == J1939_ETP) pkt = j1939_etp_ctl_to_packet(dat); else pkt = dat[2]; if (!pkt) goto out_session_cancel; else if (dat[1] > session->pkt.block /* 0xff for etp */) goto out_session_cancel; /* set packet counters only when not CTS(0) */ session->pkt.tx_acked = pkt - 1; j1939_session_skb_drop_old(session); session->pkt.last = session->pkt.tx_acked + dat[1]; if (session->pkt.last > session->pkt.total) /* safety measure */ session->pkt.last = session->pkt.total; /* TODO: do not set tx here, do it in txtimer */ session->pkt.tx = session->pkt.tx_acked; session->last_cmd = dat[0]; if (dat[1]) { j1939_tp_set_rxtimeout(session, 1250); if (session->transmission) { if (session->pkt.tx_acked) j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_SCHED); j1939_session_txtimer_cancel(session); j1939_tp_schedule_txtimer(session, 0); } } else { /* CTS(0) */ j1939_tp_set_rxtimeout(session, 550); } return; out_session_cancel: j1939_session_timers_cancel(session); j1939_session_cancel(session, err); } static void j1939_xtp_rx_cts(struct j1939_priv *priv, struct sk_buff *skb, bool transmitter) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_session *session; session = j1939_session_get_by_addr(priv, &skcb->addr, true, transmitter); if (!session) return; j1939_xtp_rx_cts_one(session, skb); j1939_session_put(session); } static struct j1939_session *j1939_session_new(struct j1939_priv *priv, struct sk_buff *skb, size_t size) { struct j1939_session *session; struct j1939_sk_buff_cb *skcb; session = kzalloc(sizeof(*session), gfp_any()); if (!session) return NULL; INIT_LIST_HEAD(&session->active_session_list_entry); INIT_LIST_HEAD(&session->sk_session_queue_entry); kref_init(&session->kref); j1939_priv_get(priv); session->priv = priv; session->total_message_size = size; session->state = J1939_SESSION_NEW; skb_queue_head_init(&session->skb_queue); skb_queue_tail(&session->skb_queue, skb); skcb = j1939_skb_to_cb(skb); memcpy(&session->skcb, skcb, sizeof(session->skcb)); hrtimer_init(&session->txtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); session->txtimer.function = j1939_tp_txtimer; hrtimer_init(&session->rxtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); session->rxtimer.function = j1939_tp_rxtimer; netdev_dbg(priv->ndev, "%s: 0x%p: sa: %02x, da: %02x\n", __func__, session, skcb->addr.sa, skcb->addr.da); return session; } static struct j1939_session *j1939_session_fresh_new(struct j1939_priv *priv, int size, const struct j1939_sk_buff_cb *rel_skcb) { struct sk_buff *skb; struct j1939_sk_buff_cb *skcb; struct j1939_session *session; skb = alloc_skb(size + sizeof(struct can_skb_priv), GFP_ATOMIC); if (unlikely(!skb)) return NULL; skb->dev = priv->ndev; can_skb_reserve(skb); can_skb_prv(skb)->ifindex = priv->ndev->ifindex; can_skb_prv(skb)->skbcnt = 0; skcb = j1939_skb_to_cb(skb); memcpy(skcb, rel_skcb, sizeof(*skcb)); session = j1939_session_new(priv, skb, size); if (!session) { kfree_skb(skb); return NULL; } /* alloc data area */ skb_put(skb, size); /* skb is recounted in j1939_session_new() */ return session; } int j1939_session_activate(struct j1939_session *session) { struct j1939_priv *priv = session->priv; struct j1939_session *active = NULL; int ret = 0; j1939_session_list_lock(priv); if (session->skcb.addr.type != J1939_SIMPLE) active = j1939_session_get_by_addr_locked(priv, &priv->active_session_list, &session->skcb.addr, false, session->transmission); if (active) { j1939_session_put(active); ret = -EAGAIN; } else { WARN_ON_ONCE(session->state != J1939_SESSION_NEW); list_add_tail(&session->active_session_list_entry, &priv->active_session_list); j1939_session_get(session); session->state = J1939_SESSION_ACTIVE; netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); } j1939_session_list_unlock(priv); return ret; } static struct j1939_session *j1939_xtp_rx_rts_session_new(struct j1939_priv *priv, struct sk_buff *skb) { enum j1939_xtp_abort abort = J1939_XTP_NO_ABORT; struct j1939_sk_buff_cb skcb = *j1939_skb_to_cb(skb); struct j1939_session *session; const u8 *dat; int len, ret; pgn_t pgn; netdev_dbg(priv->ndev, "%s\n", __func__); dat = skb->data; pgn = j1939_xtp_ctl_to_pgn(dat); skcb.addr.pgn = pgn; if (!j1939_sk_recv_match(priv, &skcb)) return NULL; if (skcb.addr.type == J1939_ETP) { len = j1939_etp_ctl_to_size(dat); if (len > J1939_MAX_ETP_PACKET_SIZE) abort = J1939_XTP_ABORT_FAULT; else if (len > priv->tp_max_packet_size) abort = J1939_XTP_ABORT_RESOURCE; else if (len <= J1939_MAX_TP_PACKET_SIZE) abort = J1939_XTP_ABORT_FAULT; } else { len = j1939_tp_ctl_to_size(dat); if (len > J1939_MAX_TP_PACKET_SIZE) abort = J1939_XTP_ABORT_FAULT; else if (len > priv->tp_max_packet_size) abort = J1939_XTP_ABORT_RESOURCE; else if (len < J1939_MIN_TP_PACKET_SIZE) abort = J1939_XTP_ABORT_FAULT; } if (abort != J1939_XTP_NO_ABORT) { j1939_xtp_tx_abort(priv, &skcb, true, abort, pgn); return NULL; } session = j1939_session_fresh_new(priv, len, &skcb); if (!session) { j1939_xtp_tx_abort(priv, &skcb, true, J1939_XTP_ABORT_RESOURCE, pgn); return NULL; } /* initialize the control buffer: plain copy */ session->pkt.total = (len + 6) / 7; session->pkt.block = 0xff; if (skcb.addr.type != J1939_ETP) { if (dat[3] != session->pkt.total) netdev_alert(priv->ndev, "%s: 0x%p: strange total, %u != %u\n", __func__, session, session->pkt.total, dat[3]); session->pkt.total = dat[3]; session->pkt.block = min(dat[3], dat[4]); } session->pkt.rx = 0; session->pkt.tx = 0; session->tskey = priv->rx_tskey++; j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_RTS); ret = j1939_session_activate(session); if (ret) { /* Entering this scope indicates an issue with the J1939 bus. * Possible scenarios include: * - A time lapse occurred, and a new session was initiated * due to another packet being sent correctly. This could * have been caused by too long interrupt, debugger, or being * out-scheduled by another task. * - The bus is receiving numerous erroneous packets, either * from a malfunctioning device or during a test scenario. */ netdev_alert(priv->ndev, "%s: 0x%p: concurrent session with same addr (%02x %02x) is already active.\n", __func__, session, skcb.addr.sa, skcb.addr.da); j1939_session_put(session); return NULL; } return session; } static int j1939_xtp_rx_rts_session_active(struct j1939_session *session, struct sk_buff *skb) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_priv *priv = session->priv; if (!session->transmission) { if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) return -EBUSY; /* RTS on active session */ j1939_session_timers_cancel(session); j1939_session_cancel(session, J1939_XTP_ABORT_BUSY); } if (session->last_cmd != 0) { /* we received a second rts on the same connection */ netdev_alert(priv->ndev, "%s: 0x%p: connection exists (%02x %02x). last cmd: %x\n", __func__, session, skcb->addr.sa, skcb->addr.da, session->last_cmd); j1939_session_timers_cancel(session); j1939_session_cancel(session, J1939_XTP_ABORT_BUSY); if (session->transmission) j1939_session_deactivate_activate_next(session); return -EBUSY; } if (session->skcb.addr.sa != skcb->addr.sa || session->skcb.addr.da != skcb->addr.da) netdev_warn(priv->ndev, "%s: 0x%p: session->skcb.addr.sa=0x%02x skcb->addr.sa=0x%02x session->skcb.addr.da=0x%02x skcb->addr.da=0x%02x\n", __func__, session, session->skcb.addr.sa, skcb->addr.sa, session->skcb.addr.da, skcb->addr.da); /* make sure 'sa' & 'da' are correct ! * They may be 'not filled in yet' for sending * skb's, since they did not pass the Address Claim ever. */ session->skcb.addr.sa = skcb->addr.sa; session->skcb.addr.da = skcb->addr.da; netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); return 0; } static void j1939_xtp_rx_rts(struct j1939_priv *priv, struct sk_buff *skb, bool transmitter) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_session *session; u8 cmd = skb->data[0]; session = j1939_session_get_by_addr(priv, &skcb->addr, false, transmitter); if (!session) { if (transmitter) { /* If we're the transmitter and this function is called, * we received our own RTS. A session has already been * created. * * For some reasons however it might have been destroyed * already. So don't create a new one here (using * "j1939_xtp_rx_rts_session_new()") as this will be a * receiver session. * * The reasons the session is already destroyed might * be: * - user space closed socket was and the session was * aborted * - session was aborted due to external abort message */ return; } session = j1939_xtp_rx_rts_session_new(priv, skb); if (!session) { if (cmd == J1939_TP_CMD_BAM && j1939_sk_recv_match(priv, skcb)) netdev_info(priv->ndev, "%s: failed to create TP BAM session\n", __func__); return; } } else { if (j1939_xtp_rx_rts_session_active(session, skb)) { j1939_session_put(session); return; } } session->last_cmd = cmd; if (cmd == J1939_TP_CMD_BAM) { if (!session->transmission) j1939_tp_set_rxtimeout(session, 750); } else { if (!session->transmission) { j1939_session_txtimer_cancel(session); j1939_tp_schedule_txtimer(session, 0); } j1939_tp_set_rxtimeout(session, 1250); } j1939_session_put(session); } static void j1939_xtp_rx_dpo_one(struct j1939_session *session, struct sk_buff *skb) { const u8 *dat = skb->data; if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) return; netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); /* transmitted without problems */ session->pkt.dpo = j1939_etp_ctl_to_packet(skb->data); session->last_cmd = dat[0]; j1939_tp_set_rxtimeout(session, 750); if (!session->transmission) j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_DPO); } static void j1939_xtp_rx_dpo(struct j1939_priv *priv, struct sk_buff *skb, bool transmitter) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_session *session; session = j1939_session_get_by_addr(priv, &skcb->addr, false, transmitter); if (!session) { netdev_info(priv->ndev, "%s: no connection found\n", __func__); return; } j1939_xtp_rx_dpo_one(session, skb); j1939_session_put(session); } static void j1939_xtp_rx_dat_one(struct j1939_session *session, struct sk_buff *skb) { enum j1939_xtp_abort abort = J1939_XTP_ABORT_FAULT; struct j1939_priv *priv = session->priv; struct j1939_sk_buff_cb *skcb, *se_skcb; struct sk_buff *se_skb = NULL; const u8 *dat; u8 *tpdat; int offset; int nbytes; bool final = false; bool remain = false; bool do_cts_eoma = false; int packet; skcb = j1939_skb_to_cb(skb); dat = skb->data; if (skb->len != 8) { /* makes no sense */ abort = J1939_XTP_ABORT_UNEXPECTED_DATA; goto out_session_cancel; } switch (session->last_cmd) { case 0xff: break; case J1939_ETP_CMD_DPO: if (skcb->addr.type == J1939_ETP) break; fallthrough; case J1939_TP_CMD_BAM: fallthrough; case J1939_TP_CMD_CTS: if (skcb->addr.type != J1939_ETP) break; fallthrough; default: netdev_info(priv->ndev, "%s: 0x%p: last %02x\n", __func__, session, session->last_cmd); goto out_session_cancel; } packet = (dat[0] - 1 + session->pkt.dpo); if (packet > session->pkt.total || (session->pkt.rx + 1) > session->pkt.total) { netdev_info(priv->ndev, "%s: 0x%p: should have been completed\n", __func__, session); goto out_session_cancel; } se_skb = j1939_session_skb_get_by_offset(session, packet * 7); if (!se_skb) { netdev_warn(priv->ndev, "%s: 0x%p: no skb found\n", __func__, session); goto out_session_cancel; } se_skcb = j1939_skb_to_cb(se_skb); offset = packet * 7 - se_skcb->offset; nbytes = se_skb->len - offset; if (nbytes > 7) nbytes = 7; if (nbytes <= 0 || (nbytes + 1) > skb->len) { netdev_info(priv->ndev, "%s: 0x%p: nbytes %i, len %i\n", __func__, session, nbytes, skb->len); goto out_session_cancel; } tpdat = se_skb->data; if (!session->transmission) { memcpy(&tpdat[offset], &dat[1], nbytes); } else { int err; err = memcmp(&tpdat[offset], &dat[1], nbytes); if (err) netdev_err_once(priv->ndev, "%s: 0x%p: Data of RX-looped back packet (%*ph) doesn't match TX data (%*ph)!\n", __func__, session, nbytes, &dat[1], nbytes, &tpdat[offset]); } if (packet == session->pkt.rx) session->pkt.rx++; if (se_skcb->addr.type != J1939_ETP && j1939_cb_is_broadcast(&session->skcb)) { if (session->pkt.rx >= session->pkt.total) final = true; else remain = true; } else { /* never final, an EOMA must follow */ if (session->pkt.rx >= session->pkt.last) do_cts_eoma = true; } if (final) { j1939_session_timers_cancel(session); j1939_session_completed(session); } else if (remain) { if (!session->transmission) j1939_tp_set_rxtimeout(session, 750); } else if (do_cts_eoma) { j1939_tp_set_rxtimeout(session, 1250); if (!session->transmission) j1939_tp_schedule_txtimer(session, 0); } else { j1939_tp_set_rxtimeout(session, 750); } session->last_cmd = 0xff; consume_skb(se_skb); j1939_session_put(session); return; out_session_cancel: kfree_skb(se_skb); j1939_session_timers_cancel(session); j1939_session_cancel(session, abort); j1939_session_put(session); } static void j1939_xtp_rx_dat(struct j1939_priv *priv, struct sk_buff *skb) { struct j1939_sk_buff_cb *skcb; struct j1939_session *session; skcb = j1939_skb_to_cb(skb); if (j1939_tp_im_transmitter(skcb)) { session = j1939_session_get_by_addr(priv, &skcb->addr, false, true); if (!session) netdev_info(priv->ndev, "%s: no tx connection found\n", __func__); else j1939_xtp_rx_dat_one(session, skb); } if (j1939_tp_im_receiver(skcb)) { session = j1939_session_get_by_addr(priv, &skcb->addr, false, false); if (!session) netdev_info(priv->ndev, "%s: no rx connection found\n", __func__); else j1939_xtp_rx_dat_one(session, skb); } if (j1939_cb_is_broadcast(skcb)) { session = j1939_session_get_by_addr(priv, &skcb->addr, false, false); if (session) j1939_xtp_rx_dat_one(session, skb); } } /* j1939 main intf */ struct j1939_session *j1939_tp_send(struct j1939_priv *priv, struct sk_buff *skb, size_t size) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); struct j1939_session *session; int ret; if (skcb->addr.pgn == J1939_TP_PGN_DAT || skcb->addr.pgn == J1939_TP_PGN_CTL || skcb->addr.pgn == J1939_ETP_PGN_DAT || skcb->addr.pgn == J1939_ETP_PGN_CTL) /* avoid conflict */ return ERR_PTR(-EDOM); if (size > priv->tp_max_packet_size) return ERR_PTR(-EMSGSIZE); if (size <= 8) skcb->addr.type = J1939_SIMPLE; else if (size > J1939_MAX_TP_PACKET_SIZE) skcb->addr.type = J1939_ETP; else skcb->addr.type = J1939_TP; if (skcb->addr.type == J1939_ETP && j1939_cb_is_broadcast(skcb)) return ERR_PTR(-EDESTADDRREQ); /* fill in addresses from names */ ret = j1939_ac_fixup(priv, skb); if (unlikely(ret)) return ERR_PTR(ret); /* fix DST flags, it may be used there soon */ if (j1939_address_is_unicast(skcb->addr.da) && priv->ents[skcb->addr.da].nusers) skcb->flags |= J1939_ECU_LOCAL_DST; /* src is always local, I'm sending ... */ skcb->flags |= J1939_ECU_LOCAL_SRC; /* prepare new session */ session = j1939_session_new(priv, skb, size); if (!session) return ERR_PTR(-ENOMEM); /* skb is recounted in j1939_session_new() */ sock_hold(skb->sk); session->sk = skb->sk; session->transmission = true; session->pkt.total = (size + 6) / 7; session->pkt.block = skcb->addr.type == J1939_ETP ? 255 : min(j1939_tp_block ?: 255, session->pkt.total); if (j1939_cb_is_broadcast(&session->skcb)) /* set the end-packet for broadcast */ session->pkt.last = session->pkt.total; skcb->tskey = atomic_inc_return(&session->sk->sk_tskey) - 1; session->tskey = skcb->tskey; return session; } static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); int extd = J1939_TP; u8 cmd = skb->data[0]; switch (cmd) { case J1939_ETP_CMD_RTS: extd = J1939_ETP; fallthrough; case J1939_TP_CMD_BAM: if (cmd == J1939_TP_CMD_BAM && !j1939_cb_is_broadcast(skcb)) { netdev_err_once(priv->ndev, "%s: BAM to unicast (%02x), ignoring!\n", __func__, skcb->addr.sa); return; } fallthrough; case J1939_TP_CMD_RTS: if (skcb->addr.type != extd) return; if (cmd == J1939_TP_CMD_RTS && j1939_cb_is_broadcast(skcb)) { netdev_alert(priv->ndev, "%s: rts without destination (%02x)\n", __func__, skcb->addr.sa); return; } if (j1939_tp_im_transmitter(skcb)) j1939_xtp_rx_rts(priv, skb, true); if (j1939_tp_im_receiver(skcb) || j1939_cb_is_broadcast(skcb)) j1939_xtp_rx_rts(priv, skb, false); break; case J1939_ETP_CMD_CTS: extd = J1939_ETP; fallthrough; case J1939_TP_CMD_CTS: if (skcb->addr.type != extd) return; if (j1939_tp_im_transmitter(skcb)) j1939_xtp_rx_cts(priv, skb, false); if (j1939_tp_im_receiver(skcb)) j1939_xtp_rx_cts(priv, skb, true); break; case J1939_ETP_CMD_DPO: if (skcb->addr.type != J1939_ETP) return; if (j1939_tp_im_transmitter(skcb)) j1939_xtp_rx_dpo(priv, skb, true); if (j1939_tp_im_receiver(skcb)) j1939_xtp_rx_dpo(priv, skb, false); break; case J1939_ETP_CMD_EOMA: extd = J1939_ETP; fallthrough; case J1939_TP_CMD_EOMA: if (skcb->addr.type != extd) return; if (j1939_tp_im_transmitter(skcb)) j1939_xtp_rx_eoma(priv, skb, false); if (j1939_tp_im_receiver(skcb)) j1939_xtp_rx_eoma(priv, skb, true); break; case J1939_ETP_CMD_ABORT: /* && J1939_TP_CMD_ABORT */ if (j1939_cb_is_broadcast(skcb)) { netdev_err_once(priv->ndev, "%s: abort to broadcast (%02x), ignoring!\n", __func__, skcb->addr.sa); return; } if (j1939_tp_im_transmitter(skcb)) j1939_xtp_rx_abort(priv, skb, true); if (j1939_tp_im_receiver(skcb)) j1939_xtp_rx_abort(priv, skb, false); break; default: return; } } int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb) { struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); if (!j1939_tp_im_involved_anydir(skcb) && !j1939_cb_is_broadcast(skcb)) return 0; switch (skcb->addr.pgn) { case J1939_ETP_PGN_DAT: skcb->addr.type = J1939_ETP; fallthrough; case J1939_TP_PGN_DAT: j1939_xtp_rx_dat(priv, skb); break; case J1939_ETP_PGN_CTL: skcb->addr.type = J1939_ETP; fallthrough; case J1939_TP_PGN_CTL: if (skb->len < 8) return 0; /* Don't care. Nothing to extract here */ j1939_tp_cmd_recv(priv, skb); break; default: return 0; /* no problem */ } return 1; /* "I processed the message" */ } void j1939_simple_recv(struct j1939_priv *priv, struct sk_buff *skb) { struct j1939_session *session; if (!skb->sk) return; if (skb->sk->sk_family != AF_CAN || skb->sk->sk_protocol != CAN_J1939) return; j1939_session_list_lock(priv); session = j1939_session_get_simple(priv, skb); j1939_session_list_unlock(priv); if (!session) { netdev_warn(priv->ndev, "%s: Received already invalidated message\n", __func__); return; } j1939_session_timers_cancel(session); j1939_session_deactivate(session); j1939_session_put(session); } int j1939_cancel_active_session(struct j1939_priv *priv, struct sock *sk) { struct j1939_session *session, *saved; netdev_dbg(priv->ndev, "%s, sk: %p\n", __func__, sk); j1939_session_list_lock(priv); list_for_each_entry_safe(session, saved, &priv->active_session_list, active_session_list_entry) { if (!sk || sk == session->sk) { if (hrtimer_try_to_cancel(&session->txtimer) == 1) j1939_session_put(session); if (hrtimer_try_to_cancel(&session->rxtimer) == 1) j1939_session_put(session); session->err = ESHUTDOWN; j1939_session_deactivate_locked(session); } } j1939_session_list_unlock(priv); return NOTIFY_DONE; } void j1939_tp_init(struct j1939_priv *priv) { spin_lock_init(&priv->active_session_list_lock); INIT_LIST_HEAD(&priv->active_session_list); priv->tp_max_packet_size = J1939_MAX_ETP_PACKET_SIZE; }