/* * Copyright (c) 2015, SICS Swedish ICT. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * This file is part of the Contiki operating system. * */ /** * \file * IEEE 802.15.4e Information Element (IE) creation and parsing. * \author * Simon Duquennoy */ #include #include "net/mac/framer/frame802154e-ie.h" /* Log configuration */ #include "sys/log.h" #define LOG_MODULE "Frame 15.4" #define LOG_LEVEL LOG_LEVEL_FRAMER /* c.f. IEEE 802.15.4e Table 4b */ enum ieee802154e_header_ie_id { HEADER_IE_LE_CSL = 0x1a, HEADER_IE_LE_RIT, HEADER_IE_DSME_PAN_DESCRIPTOR, HEADER_IE_RZ_TIME, HEADER_IE_ACK_NACK_TIME_CORRECTION, HEADER_IE_GACK, HEADER_IE_LOW_LATENCY_NETWORK_INFO, HEADER_IE_LIST_TERMINATION_1 = 0x7e, HEADER_IE_LIST_TERMINATION_2 = 0x7f, }; /* c.f. IEEE 802.15.4e Table 4c */ enum ieee802154e_payload_ie_id { PAYLOAD_IE_ESDU = 0, PAYLOAD_IE_MLME, PAYLOAD_IE_IETF = 0x5, PAYLOAD_IE_LIST_TERMINATION = 0xf, }; /* c.f. IEEE 802.15.4e Table 4d */ enum ieee802154e_mlme_short_subie_id { MLME_SHORT_IE_TSCH_SYNCHRONIZATION = 0x1a, MLME_SHORT_IE_TSCH_SLOFTRAME_AND_LINK, MLME_SHORT_IE_TSCH_TIMESLOT, MLME_SHORT_IE_TSCH_HOPPING_TIMING, MLME_SHORT_IE_TSCH_EB_FILTER, MLME_SHORT_IE_TSCH_MAC_METRICS_1, MLME_SHORT_IE_TSCH_MAC_METRICS_2, }; /* c.f. IEEE 802.15.4e Table 4e */ enum ieee802154e_mlme_long_subie_id { MLME_LONG_IE_TSCH_CHANNEL_HOPPING_SEQUENCE = 0x9, }; #include enum ieee802154e_ietf_subie_id { IETF_IE_6TOP = SIXTOP_SUBIE_ID, }; #define WRITE16(buf, val) \ do { ((uint8_t *)(buf))[0] = (val) & 0xff; \ ((uint8_t *)(buf))[1] = ((val) >> 8) & 0xff; } while(0); #define READ16(buf, var) \ (var) = ((uint8_t *)(buf))[0] | ((uint8_t *)(buf))[1] << 8 /* Create a header IE 2-byte descriptor */ static void create_header_ie_descriptor(uint8_t *buf, uint8_t element_id, int ie_len) { uint16_t ie_desc; /* Header IE descriptor: b0-6: len, b7-14: element id:, b15: type: 0 */ ie_desc = (ie_len & 0x7f) + ((element_id & 0xff) << 7); WRITE16(buf, ie_desc); } /* Create a payload IE 2-byte descriptor */ static void create_payload_ie_descriptor(uint8_t *buf, uint8_t group_id, int ie_len) { uint16_t ie_desc; /* MLME Long IE descriptor: b0-10: len, b11-14: group id:, b15: type: 1 */ ie_desc = (ie_len & 0x07ff) + ((group_id & 0x0f) << 11) + (1 << 15); WRITE16(buf, ie_desc); } /* Create a MLME short IE 2-byte descriptor */ static void create_mlme_short_ie_descriptor(uint8_t *buf, uint8_t sub_id, int ie_len) { uint16_t ie_desc; /* MLME Short IE descriptor: b0-7: len, b8-14: sub id:, b15: type: 0 */ ie_desc = (ie_len & 0xff) + ((sub_id & 0x7f) << 8); WRITE16(buf, ie_desc); } /* Create a MLME long IE 2-byte descriptor */ static void create_mlme_long_ie_descriptor(uint8_t *buf, uint8_t sub_id, int ie_len) { uint16_t ie_desc; /* MLME Long IE descriptor: b0-10: len, b11-14: sub id:, b15: type: 1 */ ie_desc = (ie_len & 0x07ff) + ((sub_id & 0x0f) << 11) + (1 << 15); WRITE16(buf, ie_desc); } /* Header IE. ACK/NACK time correction. Used in enhanced ACKs */ int frame80215e_create_ie_header_ack_nack_time_correction(uint8_t *buf, int len, struct ieee802154_ies *ies) { int ie_len = 2; if(len >= 2 + ie_len && ies != NULL) { int16_t drift_us; uint16_t time_sync_field; drift_us = ies->ie_time_correction; time_sync_field = drift_us & 0x0fff; if(ies->ie_is_nack) { time_sync_field |= 0x8000; } WRITE16(buf+2, time_sync_field); create_header_ie_descriptor(buf, HEADER_IE_ACK_NACK_TIME_CORRECTION, ie_len); return 2 + ie_len; } else { return -1; } } /* Header IE. List termination 1 (Signals the end of the Header IEs when * followed by payload IEs) */ int frame80215e_create_ie_header_list_termination_1(uint8_t *buf, int len, struct ieee802154_ies *ies) { int ie_len = 0; if(len >= 2 + ie_len && ies != NULL) { create_header_ie_descriptor(buf, HEADER_IE_LIST_TERMINATION_1, 0); return 2 + ie_len; } else { return -1; } } /* Header IE. List termination 2 (Signals the end of the Header IEs when * followed by an unformatted payload) */ int frame80215e_create_ie_header_list_termination_2(uint8_t *buf, int len, struct ieee802154_ies *ies) { int ie_len = 0; if(len >= 2 + ie_len && ies != NULL) { create_header_ie_descriptor(buf, HEADER_IE_LIST_TERMINATION_2, 0); return 2 + ie_len; } else { return -1; } } /* Payload IE. List termination */ int frame80215e_create_ie_payload_list_termination(uint8_t *buf, int len, struct ieee802154_ies *ies) { int ie_len = 0; if(len >= 2 + ie_len && ies != NULL) { create_payload_ie_descriptor(buf, PAYLOAD_IE_LIST_TERMINATION, 0); return 2 + ie_len; } else { return -1; } } #if TSCH_WITH_SIXTOP /* Payload IE. 6top. Used to nest sub-IEs */ int frame80215e_create_ie_ietf(uint8_t *buf, int len, struct ieee802154_ies *ies) { if(len >= 2 && ies != NULL) { create_payload_ie_descriptor(buf, PAYLOAD_IE_IETF, ies->sixtop_ie_content_len); return 2 + ies->sixtop_ie_content_len; } return -1; } #endif /* TSCH_WITH_SIXTOP */ /* Payload IE. MLME. Used to nest sub-IEs */ int frame80215e_create_ie_mlme(uint8_t *buf, int len, struct ieee802154_ies *ies) { int ie_len = 0; if(len >= 2 + ie_len && ies != NULL) { /* The length of the outer MLME IE is the total length of sub-IEs */ create_payload_ie_descriptor(buf, PAYLOAD_IE_MLME, ies->ie_mlme_len); return 2 + ie_len; } else { return -1; } } /* MLME sub-IE. TSCH synchronization. Used in EBs: ASN and join priority */ int frame80215e_create_ie_tsch_synchronization(uint8_t *buf, int len, struct ieee802154_ies *ies) { int ie_len = 6; if(len >= 2 + ie_len && ies != NULL) { buf[2] = ies->ie_asn.ls4b; buf[3] = ies->ie_asn.ls4b >> 8; buf[4] = ies->ie_asn.ls4b >> 16; buf[5] = ies->ie_asn.ls4b >> 24; buf[6] = ies->ie_asn.ms1b; buf[7] = ies->ie_join_priority; create_mlme_short_ie_descriptor(buf, MLME_SHORT_IE_TSCH_SYNCHRONIZATION, ie_len); return 2 + ie_len; } else { return -1; } } /* MLME sub-IE. TSCH slotframe and link. Used in EBs: initial schedule */ int frame80215e_create_ie_tsch_slotframe_and_link(uint8_t *buf, int len, struct ieee802154_ies *ies) { if(ies != NULL) { int i; int num_slotframes = ies->ie_tsch_slotframe_and_link.num_slotframes; int num_links = ies->ie_tsch_slotframe_and_link.num_links; int ie_len = 1 + num_slotframes * (4 + 5 * num_links); if(num_slotframes > 1 || num_links > FRAME802154E_IE_MAX_LINKS || len < 2 + ie_len) { /* We support only 0 or 1 slotframe in this IE and a predefined maximum number of links */ return -1; } /* Insert IE */ buf[2] = num_slotframes; /* Insert slotframe */ if(num_slotframes == 1) { buf[2 + 1] = ies->ie_tsch_slotframe_and_link.slotframe_handle; WRITE16(buf + 2 + 2, ies->ie_tsch_slotframe_and_link.slotframe_size); buf[2 + 4] = num_links; /* Loop over links */ for(i = 0; i < num_links; i++) { /* Insert links */ WRITE16(buf + 2 + 5 + i * 5, ies->ie_tsch_slotframe_and_link.links[i].timeslot); WRITE16(buf + 2 + 5 + i * 5 + 2, ies->ie_tsch_slotframe_and_link.links[i].channel_offset); buf[2 + 5 + i * 5 + 4] = ies->ie_tsch_slotframe_and_link.links[i].link_options; } } create_mlme_short_ie_descriptor(buf, MLME_SHORT_IE_TSCH_SLOFTRAME_AND_LINK, ie_len); return 2 + ie_len; } else { return -1; } } /* MLME sub-IE. TSCH timeslot. Used in EBs: timeslot template (timing) */ int frame80215e_create_ie_tsch_timeslot(uint8_t *buf, int len, struct ieee802154_ies *ies) { int ie_len; if(ies == NULL) { return -1; } /* Only ID if ID == 0, else full timing description */ ie_len = ies->ie_tsch_timeslot_id == 0 ? 1 : 25; if(len >= 2 + ie_len) { buf[2] = ies->ie_tsch_timeslot_id; if(ies->ie_tsch_timeslot_id != 0) { int i; for(i = 0; i < tsch_ts_elements_count; i++) { WRITE16(buf + 3 + 2 * i, ies->ie_tsch_timeslot[i]); } } create_mlme_short_ie_descriptor(buf, MLME_SHORT_IE_TSCH_TIMESLOT, ie_len); return 2 + ie_len; } else { return -1; } } /* MLME sub-IE. TSCH channel hopping sequence. Used in EBs: hopping sequence */ int frame80215e_create_ie_tsch_channel_hopping_sequence(uint8_t *buf, int len, struct ieee802154_ies *ies) { int ie_len; if(ies == NULL || ies->ie_hopping_sequence_len > sizeof(ies->ie_hopping_sequence_list)) { return -1; } ie_len = ies->ie_channel_hopping_sequence_id == 0 ? 1 : 12 + ies->ie_hopping_sequence_len; if(len >= 2 + ie_len && ies != NULL) { buf[2] = ies->ie_channel_hopping_sequence_id; buf[3] = 0; /* channel page */ WRITE16(buf + 4, 0); /* number of channels */ WRITE16(buf + 6, 0); /* phy configuration */ WRITE16(buf + 8, 0); /* Extended bitmap. Size: 0 */ WRITE16(buf + 10, ies->ie_hopping_sequence_len); /* sequence len */ memcpy(buf + 12, ies->ie_hopping_sequence_list, ies->ie_hopping_sequence_len); /* sequence list */ WRITE16(buf + 12 + ies->ie_hopping_sequence_len, 0); /* current hop */ create_mlme_long_ie_descriptor(buf, MLME_LONG_IE_TSCH_CHANNEL_HOPPING_SEQUENCE, ie_len); return 2 + ie_len; } else { return -1; } } /* Parse a header IE */ static int frame802154e_parse_header_ie(const uint8_t *buf, int len, uint8_t element_id, struct ieee802154_ies *ies) { switch(element_id) { case HEADER_IE_ACK_NACK_TIME_CORRECTION: if(len == 2) { if(ies != NULL) { /* If the originator was a time source neighbor, the receiver adjust * its own clock by incorporating the received drift correction */ uint16_t time_sync_field = 0; int16_t drift_us = 0; /* Extract drift correction from Sync-IE, cast from 12 to 16-bit, * and convert it to RTIMER ticks. * See page 88 in IEEE Std 802.15.4e-2012. */ READ16(buf, time_sync_field); /* First extract NACK */ ies->ie_is_nack = (time_sync_field & (uint16_t)0x8000) ? 1 : 0; /* Then cast from 12 to 16 bit signed */ if(time_sync_field & 0x0800) { /* Negative integer */ drift_us = time_sync_field | 0xf000; } else { /* Positive integer */ drift_us = time_sync_field & 0x0fff; } /* Convert to RTIMER ticks */ ies->ie_time_correction = drift_us; } return len; } break; } return -1; } /* Parse a MLME short IE */ static int frame802154e_parse_mlme_short_ie(const uint8_t *buf, int len, uint8_t sub_id, struct ieee802154_ies *ies) { switch(sub_id) { case MLME_SHORT_IE_TSCH_SLOFTRAME_AND_LINK: if(len >= 1) { int i; int num_slotframes = buf[0]; int num_links = buf[4]; if(num_slotframes == 0) { return len; } if(num_slotframes <= 1 && num_links <= FRAME802154E_IE_MAX_LINKS && len == 1 + num_slotframes * (4 + 5 * num_links)) { if(ies != NULL) { /* We support only 0 or 1 slotframe in this IE and a predefined maximum number of links */ ies->ie_tsch_slotframe_and_link.num_slotframes = buf[0]; ies->ie_tsch_slotframe_and_link.slotframe_handle = buf[1]; READ16(buf + 2, ies->ie_tsch_slotframe_and_link.slotframe_size); ies->ie_tsch_slotframe_and_link.num_links = buf[4]; for(i = 0; i < num_links; i++) { READ16(buf + 5 + i * 5, ies->ie_tsch_slotframe_and_link.links[i].timeslot); READ16(buf + 5 + i * 5 + 2, ies->ie_tsch_slotframe_and_link.links[i].channel_offset); ies->ie_tsch_slotframe_and_link.links[i].link_options = buf[5 + i * 5 + 4]; } } return len; } } break; case MLME_SHORT_IE_TSCH_SYNCHRONIZATION: if(len == 6) { if(ies != NULL) { ies->ie_asn.ls4b = (uint32_t)buf[0]; ies->ie_asn.ls4b |= (uint32_t)buf[1] << 8; ies->ie_asn.ls4b |= (uint32_t)buf[2] << 16; ies->ie_asn.ls4b |= (uint32_t)buf[3] << 24; ies->ie_asn.ms1b = (uint8_t)buf[4]; ies->ie_join_priority = (uint8_t)buf[5]; } return len; } break; case MLME_SHORT_IE_TSCH_TIMESLOT: if(len == 1 || len == 25) { if(ies != NULL) { ies->ie_tsch_timeslot_id = buf[0]; if(len == 25) { int i; for(i = 0; i < tsch_ts_elements_count; i++) { READ16(buf+1+2*i, ies->ie_tsch_timeslot[i]); } } } return len; } break; } return -1; } /* Parse a MLME long IE */ static int frame802154e_parse_mlme_long_ie(const uint8_t *buf, int len, uint8_t sub_id, struct ieee802154_ies *ies) { switch(sub_id) { case MLME_LONG_IE_TSCH_CHANNEL_HOPPING_SEQUENCE: if(len > 0) { if(ies != NULL) { ies->ie_channel_hopping_sequence_id = buf[0]; if(len > 1) { READ16(buf+8, ies->ie_hopping_sequence_len); /* sequence len */ if(ies->ie_hopping_sequence_len <= sizeof(ies->ie_hopping_sequence_list) && len == 12 + ies->ie_hopping_sequence_len) { memcpy(ies->ie_hopping_sequence_list, buf+10, ies->ie_hopping_sequence_len); /* sequence list */ } } } return len; } break; } return -1; } /* Parse all IEEE 802.15.4e Information Elements (IE) from a frame */ int frame802154e_parse_information_elements(const uint8_t *buf, uint8_t buf_size, struct ieee802154_ies *ies) { const uint8_t *start = buf; uint16_t ie_desc; uint8_t type; uint8_t id; uint16_t len = 0; int nested_mlme_len = 0; enum {PARSING_HEADER_IE, PARSING_PAYLOAD_IE, PARSING_MLME_SUBIE} parsing_state; if(ies == NULL) { return -1; } /* Always look for a header IE first (at least "list termination 1") */ parsing_state = PARSING_HEADER_IE; ies->ie_payload_ie_offset = 0; /* Loop over all IEs */ while(buf_size > 0) { if(buf_size < 2) { /* Not enough space for IE descriptor */ return -1; } READ16(buf, ie_desc); buf_size -= 2; buf += 2; type = ie_desc & 0x8000 ? 1 : 0; /* b15 */ LOG_DBG("ie type %u, current state %u\n", type, parsing_state); switch(parsing_state) { case PARSING_HEADER_IE: if(type != 0) { LOG_ERR("wrong type %04x\n", ie_desc); return -1; } /* Header IE: 2 bytes descriptor, c.f. fig 48n in IEEE 802.15.4e */ len = ie_desc & 0x007f; /* b0-b6 */ id = (ie_desc & 0x7f80) >> 7; /* b7-b14 */ LOG_DBG("header ie len %u id %x\n", len, id); switch(id) { case HEADER_IE_LIST_TERMINATION_1: if(len == 0) { /* End of payload IE list, now expect payload IEs */ parsing_state = PARSING_PAYLOAD_IE; ies->ie_payload_ie_offset = buf - start; /* Save IE header len */ LOG_DBG("list termination 1, look for payload IEs\n"); } else { LOG_ERR("list termination 1, wrong len %u\n", len); return -1; } break; case HEADER_IE_LIST_TERMINATION_2: /* End of IE parsing */ if(len == 0) { ies->ie_payload_ie_offset = buf - start; /* Save IE header len */ LOG_DBG("list termination 2\n"); return buf + len - start; } else { LOG_ERR("list termination 2, wrong len %u\n", len); return -1; } default: if(len > buf_size || frame802154e_parse_header_ie(buf, len, id, ies) == -1) { LOG_ERR("failed to parse\n"); return -1; } break; } break; case PARSING_PAYLOAD_IE: if(type != 1) { LOG_ERR("wrong type %04x\n", ie_desc); return -1; } /* Payload IE: 2 bytes descriptor, c.f. fig 48o in IEEE 802.15.4e */ len = ie_desc & 0x7ff; /* b0-b10 */ id = (ie_desc & 0x7800) >> 11; /* b11-b14 */ LOG_DBG("payload ie len %u id %x\n", len, id); switch(id) { case PAYLOAD_IE_MLME: /* Now expect 'len' bytes of MLME sub-IEs */ parsing_state = PARSING_MLME_SUBIE; nested_mlme_len = len; len = 0; /* Reset len as we want to read subIEs and not jump over them */ LOG_DBG("entering MLME ie with len %u\n", nested_mlme_len); break; #if TSCH_WITH_SIXTOP case PAYLOAD_IE_IETF: switch(*buf) { case IETF_IE_6TOP: /* * buf points to the Sub-ID field, a one-octet field, now; * advance it by one and use the result as the head pointer of * 6top IE Content. */ ies->sixtop_ie_content_ptr = buf + 1; /* * Similarly as above, subtract 1 (one octet) from len, which * includes the length of Sub-ID field, and use the result as * the length of 6top IE Content. */ ies->sixtop_ie_content_len = len - 1; break; default: LOG_ERR("frame802154e: unsupported IETF sub-IE %u\n", *buf); break; } break; #endif /* TSCH_WITH_SIXTOP */ case PAYLOAD_IE_LIST_TERMINATION: LOG_DBG("payload ie list termination %u\n", len); return (len == 0) ? buf + len - start : -1; default: LOG_ERR("non-supported payload ie\n"); return -1; } break; case PARSING_MLME_SUBIE: /* MLME sub-IE: 2 bytes descriptor, c.f. fig 48q in IEEE 802.15.4e */ /* type == 0 means short sub-IE, type == 1 means long sub-IE */ if(type == 0) { /* Short sub-IE, c.f. fig 48r in IEEE 802.15.4e */ len = ie_desc & 0x00ff; /* b0-b7 */ id = (ie_desc & 0x7f00) >> 8; /* b8-b14 */ LOG_DBG("short mlme ie len %u id %x\n", len, id); if(len > buf_size || frame802154e_parse_mlme_short_ie(buf, len, id, ies) == -1) { LOG_ERR("failed to parse ie\n"); return -1; } } else { /* Long sub-IE, c.f. fig 48s in IEEE 802.15.4e */ len = ie_desc & 0x7ff; /* b0-b10 */ id = (ie_desc & 0x7800) >> 11; /* b11-b14 */ LOG_DBG("long mlme ie len %u id %x\n", len, id); if(len > buf_size || frame802154e_parse_mlme_long_ie(buf, len, id, ies) == -1) { LOG_ERR("failed to parse ie\n"); return -1; } } /* Update remaining nested MLME len */ nested_mlme_len -= 2 + len; if(nested_mlme_len < 0) { LOG_ERR("found more sub-IEs than initially advertised\n"); /* We found more sub-IEs than initially advertised */ return -1; } if(nested_mlme_len == 0) { LOG_DBG("end of MLME IE parsing\n"); /* End of IE parsing, look for another payload IE */ parsing_state = PARSING_PAYLOAD_IE; } break; } buf += len; buf_size -= len; } if(parsing_state == PARSING_HEADER_IE) { ies->ie_payload_ie_offset = buf - start; /* Save IE header len */ } return buf - start; }