/* * 6LoWPAN IPv6 UDP compression according to RFC6282 * * * Authors: * Alexander Aring * * Orignal written by: * Alexander Smirnov * Jon Smirl * * 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. */ #include "nhc.h" #define LOWPAN_NHC_UDP_MASK 0xF8 #define LOWPAN_NHC_UDP_ID 0xF0 #define LOWPAN_NHC_UDP_IDLEN 1 #define LOWPAN_NHC_UDP_4BIT_PORT 0xF0B0 #define LOWPAN_NHC_UDP_4BIT_MASK 0xFFF0 #define LOWPAN_NHC_UDP_8BIT_PORT 0xF000 #define LOWPAN_NHC_UDP_8BIT_MASK 0xFF00 /* values for port compression, _with checksum_ ie bit 5 set to 0 */ /* all inline */ #define LOWPAN_NHC_UDP_CS_P_00 0xF0 /* source 16bit inline, dest = 0xF0 + 8 bit inline */ #define LOWPAN_NHC_UDP_CS_P_01 0xF1 /* source = 0xF0 + 8bit inline, dest = 16 bit inline */ #define LOWPAN_NHC_UDP_CS_P_10 0xF2 /* source & dest = 0xF0B + 4bit inline */ #define LOWPAN_NHC_UDP_CS_P_11 0xF3 /* checksum elided */ #define LOWPAN_NHC_UDP_CS_C 0x04 static int udp_uncompress(struct sk_buff *skb, size_t needed) { u8 tmp = 0, val = 0; struct udphdr uh; bool fail; int err; fail = lowpan_fetch_skb(skb, &tmp, sizeof(tmp)); pr_debug("UDP header uncompression\n"); switch (tmp & LOWPAN_NHC_UDP_CS_P_11) { case LOWPAN_NHC_UDP_CS_P_00: fail |= lowpan_fetch_skb(skb, &uh.source, sizeof(uh.source)); fail |= lowpan_fetch_skb(skb, &uh.dest, sizeof(uh.dest)); break; case LOWPAN_NHC_UDP_CS_P_01: fail |= lowpan_fetch_skb(skb, &uh.source, sizeof(uh.source)); fail |= lowpan_fetch_skb(skb, &val, sizeof(val)); uh.dest = htons(val + LOWPAN_NHC_UDP_8BIT_PORT); break; case LOWPAN_NHC_UDP_CS_P_10: fail |= lowpan_fetch_skb(skb, &val, sizeof(val)); uh.source = htons(val + LOWPAN_NHC_UDP_8BIT_PORT); fail |= lowpan_fetch_skb(skb, &uh.dest, sizeof(uh.dest)); break; case LOWPAN_NHC_UDP_CS_P_11: fail |= lowpan_fetch_skb(skb, &val, sizeof(val)); uh.source = htons(LOWPAN_NHC_UDP_4BIT_PORT + (val >> 4)); uh.dest = htons(LOWPAN_NHC_UDP_4BIT_PORT + (val & 0x0f)); break; default: BUG(); } pr_debug("uncompressed UDP ports: src = %d, dst = %d\n", ntohs(uh.source), ntohs(uh.dest)); /* checksum */ if (tmp & LOWPAN_NHC_UDP_CS_C) { pr_debug_ratelimited("checksum elided currently not supported\n"); fail = true; } else { fail |= lowpan_fetch_skb(skb, &uh.check, sizeof(uh.check)); } if (fail) return -EINVAL; /* UDP length needs to be infered from the lower layers * here, we obtain the hint from the remaining size of the * frame */ switch (lowpan_dev(skb->dev)->lltype) { case LOWPAN_LLTYPE_IEEE802154: if (lowpan_802154_cb(skb)->d_size) uh.len = htons(lowpan_802154_cb(skb)->d_size - sizeof(struct ipv6hdr)); else uh.len = htons(skb->len + sizeof(struct udphdr)); break; default: uh.len = htons(skb->len + sizeof(struct udphdr)); break; } pr_debug("uncompressed UDP length: src = %d", ntohs(uh.len)); /* replace the compressed UDP head by the uncompressed UDP * header */ err = skb_cow(skb, needed); if (unlikely(err)) return err; skb_push(skb, sizeof(struct udphdr)); skb_copy_to_linear_data(skb, &uh, sizeof(struct udphdr)); return 0; } static int udp_compress(struct sk_buff *skb, u8 **hc_ptr) { const struct udphdr *uh = udp_hdr(skb); u8 tmp; if (((ntohs(uh->source) & LOWPAN_NHC_UDP_4BIT_MASK) == LOWPAN_NHC_UDP_4BIT_PORT) && ((ntohs(uh->dest) & LOWPAN_NHC_UDP_4BIT_MASK) == LOWPAN_NHC_UDP_4BIT_PORT)) { pr_debug("UDP header: both ports compression to 4 bits\n"); /* compression value */ tmp = LOWPAN_NHC_UDP_CS_P_11; lowpan_push_hc_data(hc_ptr, &tmp, sizeof(tmp)); /* source and destination port */ tmp = ntohs(uh->dest) - LOWPAN_NHC_UDP_4BIT_PORT + ((ntohs(uh->source) - LOWPAN_NHC_UDP_4BIT_PORT) << 4); lowpan_push_hc_data(hc_ptr, &tmp, sizeof(tmp)); } else if ((ntohs(uh->dest) & LOWPAN_NHC_UDP_8BIT_MASK) == LOWPAN_NHC_UDP_8BIT_PORT) { pr_debug("UDP header: remove 8 bits of dest\n"); /* compression value */ tmp = LOWPAN_NHC_UDP_CS_P_01; lowpan_push_hc_data(hc_ptr, &tmp, sizeof(tmp)); /* source port */ lowpan_push_hc_data(hc_ptr, &uh->source, sizeof(uh->source)); /* destination port */ tmp = ntohs(uh->dest) - LOWPAN_NHC_UDP_8BIT_PORT; lowpan_push_hc_data(hc_ptr, &tmp, sizeof(tmp)); } else if ((ntohs(uh->source) & LOWPAN_NHC_UDP_8BIT_MASK) == LOWPAN_NHC_UDP_8BIT_PORT) { pr_debug("UDP header: remove 8 bits of source\n"); /* compression value */ tmp = LOWPAN_NHC_UDP_CS_P_10; lowpan_push_hc_data(hc_ptr, &tmp, sizeof(tmp)); /* source port */ tmp = ntohs(uh->source) - LOWPAN_NHC_UDP_8BIT_PORT; lowpan_push_hc_data(hc_ptr, &tmp, sizeof(tmp)); /* destination port */ lowpan_push_hc_data(hc_ptr, &uh->dest, sizeof(uh->dest)); } else { pr_debug("UDP header: can't compress\n"); /* compression value */ tmp = LOWPAN_NHC_UDP_CS_P_00; lowpan_push_hc_data(hc_ptr, &tmp, sizeof(tmp)); /* source port */ lowpan_push_hc_data(hc_ptr, &uh->source, sizeof(uh->source)); /* destination port */ lowpan_push_hc_data(hc_ptr, &uh->dest, sizeof(uh->dest)); } /* checksum is always inline */ lowpan_push_hc_data(hc_ptr, &uh->check, sizeof(uh->check)); return 0; } static void udp_nhid_setup(struct lowpan_nhc *nhc) { nhc->id[0] = LOWPAN_NHC_UDP_ID; nhc->idmask[0] = LOWPAN_NHC_UDP_MASK; } LOWPAN_NHC(nhc_udp, "RFC6282 UDP", NEXTHDR_UDP, sizeof(struct udphdr), udp_nhid_setup, LOWPAN_NHC_UDP_IDLEN, udp_uncompress, udp_compress); module_lowpan_nhc(nhc_udp); MODULE_DESCRIPTION("6LoWPAN next header RFC6282 UDP compression"); MODULE_LICENSE("GPL"); 4f9cb22c77d99ea510bd5c382a'>ib_fmr_pool.h3439logplain -rw-r--r--ib_hdrs.h4989logplain -rw-r--r--ib_mad.h27924logplain -rw-r--r--ib_marshall.h2025logplain -rw-r--r--ib_pack.h9047logplain -rw-r--r--ib_pma.h5579logplain -rw-r--r--ib_sa.h16914logplain -rw-r--r--ib_smi.h5633logplain -rw-r--r--ib_umem.h3577logplain -rw-r--r--ib_umem_odp.h5300logplain -rw-r--r--ib_verbs.h100225logplain -rw-r--r--iw_cm.h8793logplain -rw-r--r--iw_portmap.h7688logplain -rw-r--r--mr_pool.h954logplain -rw-r--r--opa_port_info.h15063logplain -rw-r--r--opa_smi.h4417logplain