From 263d9903826ffb65aec89bdf5d46f72bd183d467 Mon Sep 17 00:00:00 2001 From: Guus Sliepen Date: Mon, 8 Dec 2014 00:44:38 +0100 Subject: [PATCH] Avoid memmove() for legacy UDP packets. --- src/net.h | 12 +++++++++--- src/net_packet.c | 35 ++++++++++++++++------------------- 2 files changed, 25 insertions(+), 22 deletions(-) diff --git a/src/net.h b/src/net.h index b570d5e1..367ef714 100644 --- a/src/net.h +++ b/src/net.h @@ -87,12 +87,18 @@ typedef union sockaddr_t { typedef struct vpn_packet_t { length_t len; /* the actual number of bytes in the `data' field */ int priority; /* priority or TOS */ - node_id_t dstid; /* node ID of the final recipient */ - node_id_t srcid; /* node ID of the original sender */ - uint8_t seqno[4]; /* 32 bits sequence number (network byte order of course) */ + uint32_t seqno; /* 32 bits sequence number (network byte order of course) */ uint8_t data[MAXSIZE]; } vpn_packet_t; +typedef struct sptps_packet_t { + length_t len; /* the actual number of bytes in the `data' field */ + int priority; /* priority or TOS */ + node_id_t dstid; /* node ID of the final recipient */ + node_id_t srcid; /* node ID of the original sender */ + char data[MAXSIZE]; +} sptps_packet_t; + /* Packet types when using SPTPS */ #define PKT_COMPRESSED 1 diff --git a/src/net_packet.c b/src/net_packet.c index c3e8c624..1691f31f 100644 --- a/src/net_packet.c +++ b/src/net_packet.c @@ -348,12 +348,12 @@ static void receive_packet(node_t *n, vpn_packet_t *packet) { static bool try_mac(node_t *n, const vpn_packet_t *inpkt) { if(n->status.sptps) - return sptps_verify_datagram(&n->sptps, (char *)&inpkt->seqno, inpkt->len); + return sptps_verify_datagram(&n->sptps, ((sptps_packet_t *)inpkt)->data, inpkt->len); if(!digest_active(n->indigest) || inpkt->len < sizeof inpkt->seqno + digest_length(n->indigest)) return false; - return digest_verify(n->indigest, &inpkt->seqno, inpkt->len - digest_length(n->indigest), (const char *)&inpkt->seqno + inpkt->len - digest_length(n->indigest)); + return digest_verify(n->indigest, (const char *)&inpkt->seqno, inpkt->len - digest_length(n->indigest), (const char *)&inpkt->seqno + inpkt->len - digest_length(n->indigest)); } static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) { @@ -372,7 +372,7 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) { } return false; } - if(!sptps_receive_data(&n->sptps, (char *)&inpkt->seqno, inpkt->len)) { + if(!sptps_receive_data(&n->sptps, ((sptps_packet_t *)&inpkt)->data, inpkt->len)) { logger(DEBUG_TRAFFIC, LOG_ERR, "Got bad packet from %s (%s)", n->name, n->hostname); return false; } @@ -419,9 +419,7 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) { /* Check the sequence number */ inpkt->len -= sizeof inpkt->seqno; - uint32_t seqno; - memcpy(&seqno, inpkt->seqno, sizeof seqno); - seqno = ntohl(seqno); + uint32_t seqno = ntohl(inpkt->seqno); if(replaywin) { if(seqno != n->received_seqno + 1) { @@ -699,8 +697,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { /* Add sequence number */ - uint32_t seqno = htonl(++(n->sent_seqno)); - memcpy(inpkt->seqno, &seqno, sizeof inpkt->seqno); + inpkt->seqno = htonl(++(n->sent_seqno)); inpkt->len += sizeof inpkt->seqno; /* Encrypt the packet */ @@ -709,7 +706,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { outpkt = pkt[nextpkt++]; outlen = MAXSIZE; - if(!cipher_encrypt(n->outcipher, inpkt->seqno, inpkt->len, outpkt->seqno, &outlen, true)) { + if(!cipher_encrypt(n->outcipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) { logger(DEBUG_TRAFFIC, LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname); goto end; } @@ -721,7 +718,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { /* Add the message authentication code */ if(digest_active(n->outdigest)) { - if(!digest_create(n->outdigest, inpkt->seqno, inpkt->len, inpkt->seqno + inpkt->len)) { + if(!digest_create(n->outdigest, &inpkt->seqno, inpkt->len, &inpkt->seqno + inpkt->len)) { logger(DEBUG_TRAFFIC, LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname); goto end; } @@ -749,7 +746,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) { } #endif - if(sendto(listen_socket[sock].udp.fd, inpkt->seqno, inpkt->len, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) { + if(sendto(listen_socket[sock].udp.fd, &inpkt->seqno, inpkt->len, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) { if(sockmsgsize(sockerrno)) { if(n->maxmtu >= origlen) n->maxmtu = origlen - 1; @@ -1031,6 +1028,7 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) { void handle_incoming_vpn_data(void *data, int flags) { listen_socket_t *ls = data; vpn_packet_t pkt; + sptps_packet_t *spkt = (sptps_packet_t *)&pkt; char *hostname; sockaddr_t from = {{0}}; socklen_t fromlen = sizeof from; @@ -1038,7 +1036,7 @@ void handle_incoming_vpn_data(void *data, int flags) { node_t *to = myself; int len; - len = recvfrom(ls->udp.fd, &pkt.dstid, MAXSIZE, 0, &from.sa, &fromlen); + len = recvfrom(ls->udp.fd, &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen); if(len <= 0 || len > MAXSIZE) { if(!sockwouldblock(sockerrno)) @@ -1051,21 +1049,21 @@ void handle_incoming_vpn_data(void *data, int flags) { sockaddrunmap(&from); /* Some braindead IPv6 implementations do stupid things. */ bool direct = false; - if(len >= sizeof pkt.dstid + sizeof pkt.srcid) { - n = lookup_node_id(&pkt.srcid); + if(len >= sizeof spkt->dstid + sizeof spkt->srcid) { + n = lookup_node_id(&spkt->srcid); if(n) { node_id_t nullid = {}; - if(memcmp(&pkt.dstid, &nullid, sizeof nullid) == 0) { + if(memcmp(&spkt->dstid, &nullid, sizeof nullid) == 0) { /* A zero dstid is used to indicate a direct, non-relayed packet. */ direct = true; } else { - to = lookup_node_id(&pkt.dstid); + to = lookup_node_id(&spkt->dstid); if(!to) { logger(DEBUG_PROTOCOL, LOG_WARNING, "Received UDP packet presumably sent by %s (%s) but with unknown destination ID", n->name, n->hostname); return; } } - pkt.len -= sizeof pkt.dstid + sizeof pkt.srcid; + pkt.len -= sizeof spkt->dstid + sizeof spkt->srcid; } } @@ -1078,14 +1076,13 @@ void handle_incoming_vpn_data(void *data, int flags) { return; } - send_sptps_data_priv(to, n, 0, pkt.seqno, pkt.len); + send_sptps_data_priv(to, n, 0, spkt->data, pkt.len); return; } if(!n) { /* Most likely an old-style packet without node IDs. */ direct = true; - memmove(pkt.seqno, &pkt.dstid, sizeof pkt - offsetof(vpn_packet_t, seqno)); n = lookup_node_udp(&from); } -- 2.20.1