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softflowd.c
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softflowd.c
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/*
* Copyright 2002 Damien Miller <djm@mindrot.org> 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 is software implementation of Cisco's NetFlow(tm) traffic
* reporting system. It operates by listening (via libpcap) on a
* promiscuous interface and tracking traffic flows.
*
* Traffic flows are recorded by source/destination/protocol
* IP address or, in the case of TCP and UDP, by
* src_addr:src_port/dest_addr:dest_port/protocol
*
* Flows expire automatically after a period of inactivity (default: 1
* hour) They may also be evicted (in order of age) in situations where
* there are more flows than slots available.
*
* Netflow compatible packets are sent to a specified target host upon
* flow expiry.
*
* As this implementation watches traffic promiscuously, it is likely to
* place significant load on hosts or gateways on which it is installed.
*/
#include "common.h"
#include "sys-tree.h"
#include "convtime.h"
#include "softflowd.h"
#include "treetype.h"
#include "freelist.h"
#include "log.h"
#include "netflow9.h"
#include "ipfix.h"
#include "psamp.h"
#include <pcap.h>
#ifdef LINUX
#include <net/if.h>
#endif /* LINUX */
#define IPFIX_PORT 4739
/* Global variables */
static int verbose_flag = 0; /* Debugging flag */
static u_int16_t if_index = 0; /* "manual" interface index */
static int track_level;
static int snaplen = 0;
#ifdef ENABLE_PTHREAD
pthread_mutex_t read_mutex;
pthread_cond_t read_cond;
int use_thread;
u_char packet_data[1500];
struct pcap_pkthdr packet_header;
struct FLOW *send_expired_flows;
#endif /* ENABLE_PTHREAD */
/* Signal handler flags */
static volatile sig_atomic_t graceful_shutdown_request = 0;
/* Describes a datalink header and how to extract v4/v6 frames from it */
struct DATALINK {
int dlt; /* BPF datalink type */
int skiplen; /* Number of bytes to skip datalink header */
int ft_off; /* Datalink frametype offset */
int ft_len; /* Datalink frametype length */
int ft_is_be; /* Set if frametype is big-endian */
u_int32_t ft_mask; /* Mask applied to frametype */
u_int32_t ft_v4; /* IPv4 frametype */
u_int32_t ft_v6; /* IPv6 frametype */
};
/* Datalink types that we know about */
static const struct DATALINK lt[] = {
{DLT_EN10MB, 14, 12, 2, 1, 0xffffffff, 0x0800, 0x86dd},
{DLT_PPP, 5, 3, 2, 1, 0xffffffff, 0x0021, 0x0057},
#ifdef DLT_LINUX_SLL
{DLT_LINUX_SLL, 16, 14, 2, 1, 0xffffffff, 0x0800, 0x86dd},
#endif
{DLT_RAW, 0, 0, 1, 1, 0x000000f0, 0x0040, 0x0060},
{DLT_NULL, 4, 0, 4, 0, 0xffffffff, AF_INET, AF_INET6},
#ifdef DLT_LOOP
{DLT_LOOP, 4, 0, 4, 1, 0xffffffff, AF_INET, AF_INET6},
#endif
#ifdef DLT_PFLOG
{DLT_PFLOG, 48, 1, 1, 0, 0x000000ff, AF_INET, AF_INET6},
#endif
{-1, -1, -1, -1, -1, 0x00000000, 0xffff, 0xffff},
};
/* Netflow send functions */
typedef int (netflow_send_func_t) (struct SENDPARAMETER);
struct NETFLOW_SENDER {
int version;
netflow_send_func_t *func;
netflow_send_func_t *bidir_func;
int v6_capable;
};
/* Array of NetFlow export function that we know of. NB. nf[0] is default */
static const struct NETFLOW_SENDER nf[] = {
{5, send_netflow_v5, NULL, 0},
{1, send_netflow_v1, NULL, 0},
#ifdef ENABLE_LEGACY
{9, send_netflow_v9, NULL, 1},
#else /* ENABLE_LEGACY */
{9, send_nflow9, NULL, 1},
#endif /* ENABLE_LEGACY */
{NF_VERSION_IPFIX, send_ipfix, send_ipfix_bi, 1},
#ifdef ENABLE_NTOPNG
{SOFTFLOWD_NF_VERSION_NTOPNG, send_ntopng, NULL, 1},
#endif
};
static const struct NETFLOW_SENDER *
lookup_netflow_sender (int version) {
int i, r;
for (i = 0, r = version; i < sizeof (nf) / sizeof (struct NETFLOW_SENDER);
i++) {
if (nf[i].version == r)
return &nf[i];
}
return NULL;
}
/* Signal handlers */
static void
sighand_graceful_shutdown (int signum) {
graceful_shutdown_request = signum;
}
static void
sighand_other (int signum) {
/* XXX: this may not be completely safe */
logit (LOG_WARNING, "Exiting immediately on unexpected signal %d", signum);
_exit (0);
}
/*
* This is the flow comparison function.
*/
static int
flow_compare (struct FLOW *a, struct FLOW *b) {
/* Be careful to avoid signed vs unsigned issues here */
int r, i;
if (track_level == TRACK_FULL_VLAN || track_level == TRACK_FULL_VLAN_ETHER) {
if (a->vlanid[0] != b->vlanid[0])
return (a->vlanid[0] > b->vlanid[0] ? 1 : -1);
if (a->vlanid[1] != b->vlanid[1])
return (a->vlanid[1] > b->vlanid[1] ? 1 : -1);
}
if (track_level == TRACK_FULL_VLAN_ETHER) {
if ((r = memcmp (&a->ethermac[0], &b->ethermac[0], 6)) != 0)
return (r > 0 ? 1 : -1);
if ((r = memcmp (&a->ethermac[1], &b->ethermac[1], 6)) != 0)
return (r > 0 ? 1 : -1);
}
if (a->af != b->af)
return (a->af > b->af ? 1 : -1);
if ((r = memcmp (&a->addr[0], &b->addr[0], sizeof (a->addr[0]))) != 0)
return (r > 0 ? 1 : -1);
if ((r = memcmp (&a->addr[1], &b->addr[1], sizeof (a->addr[1]))) != 0)
return (r > 0 ? 1 : -1);
#ifdef notyet
if (a->ip6_flowlabel[0] != 0 && b->ip6_flowlabel[0] != 0 &&
a->ip6_flowlabel[0] != b->ip6_flowlabel[0])
return (a->ip6_flowlabel[0] > b->ip6_flowlabel[0] ? 1 : -1);
if (a->ip6_flowlabel[1] != 0 && b->ip6_flowlabel[1] != 0 &&
a->ip6_flowlabel[1] != b->ip6_flowlabel[1])
return (a->ip6_flowlabel[1] > b->ip6_flowlabel[1] ? 1 : -1);
#endif
if (a->protocol != b->protocol)
return (a->protocol > b->protocol ? 1 : -1);
if (a->port[0] != b->port[0])
return (ntohs (a->port[0]) > ntohs (b->port[0]) ? 1 : -1);
if (a->port[1] != b->port[1])
return (ntohs (a->port[1]) > ntohs (b->port[1]) ? 1 : -1);
if (a->mplsLabelStackDepth != b->mplsLabelStackDepth)
return (a->mplsLabelStackDepth > b->mplsLabelStackDepth ? 1 : -1);
for (i = 0; i < a->mplsLabelStackDepth; i++) {
if (a->mplsLabels[i] != b->mplsLabels[i])
return (a->mplsLabels[i] > b->mplsLabels[i] ? 1 : -1);
}
return (0);
}
/* Generate functions for flow tree */
FLOW_PROTOTYPE (FLOWS, FLOW, trp, flow_compare);
FLOW_GENERATE (FLOWS, FLOW, trp, flow_compare);
/*
* This is the expiry comparison function.
*/
static int
expiry_compare (struct EXPIRY *a, struct EXPIRY *b) {
if (a->expires_at != b->expires_at)
return (a->expires_at > b->expires_at ? 1 : -1);
/* Make expiry entries unique by comparing flow sequence */
if (a->flow->flow_seq != b->flow->flow_seq)
return (a->flow->flow_seq > b->flow->flow_seq ? 1 : -1);
return (0);
}
/* Generate functions for flow tree */
EXPIRY_PROTOTYPE (EXPIRIES, EXPIRY, trp, expiry_compare);
EXPIRY_GENERATE (EXPIRIES, EXPIRY, trp, expiry_compare);
static struct FLOW *
flow_get (struct FLOWTRACK *ft) {
return freelist_get (&ft->flow_freelist);
}
static void
flow_put (struct FLOWTRACK *ft, struct FLOW *flow) {
return freelist_put (&ft->flow_freelist, flow);
}
static struct EXPIRY *
expiry_get (struct FLOWTRACK *ft) {
return freelist_get (&ft->expiry_freelist);
}
static void
expiry_put (struct FLOWTRACK *ft, struct EXPIRY *expiry) {
return freelist_put (&ft->expiry_freelist, expiry);
}
#if 0
/* Dump a packet */
static void
dump_packet (const u_int8_t * p, int len) {
char buf[1024], tmp[3];
int i;
for (*buf = '\0', i = 0; i < len; i++) {
snprintf (tmp, sizeof (tmp), "%02x%s", p[i], i % 2 ? " " : "");
if (strlcat (buf, tmp, sizeof (buf) - 4) >= sizeof (buf) - 4) {
strlcat (buf, "...", sizeof (buf));
break;
}
}
logit (LOG_INFO, "packet len %d: %s", len, buf);
}
#endif
/* Format a time in an ISOish format */
static const char *
format_time (time_t t) {
struct tm *tm;
static char buf[32];
tm = gmtime (&t);
strftime (buf, sizeof (buf), "%Y-%m-%dT%H:%M:%S", tm);
return (buf);
}
static const char *
format_ethermac (uint8_t ethermac[6]) {
static char buf[1024];
snprintf (buf, sizeof (buf), "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
ethermac[0], ethermac[1], ethermac[2], ethermac[3],
ethermac[4], ethermac[5]);
return buf;
}
/* Format a flow in a verbose and ugly way */
static const char *
format_flow (struct FLOW *flow) {
char addr1[64], addr2[64], start_time[32], fin_time[32];
static char buf[4096];
inet_ntop (flow->af, &flow->addr[0], addr1, sizeof (addr1));
inet_ntop (flow->af, &flow->addr[1], addr2, sizeof (addr2));
snprintf (start_time, sizeof (start_time), "%s",
format_time (flow->flow_start.tv_sec));
snprintf (fin_time, sizeof (fin_time), "%s",
format_time (flow->flow_last.tv_sec));
snprintf (buf, sizeof (buf),
"seq:%" PRIu64 " [%s]:%hu <> [%s]:%hu proto:%u "
"octets>:%u packets>:%u octets<:%u packets<:%u "
"start:%s.%03lld finish:%s.%03lld tcp>:%02x tcp<:%02x "
"flowlabel>:%08x flowlabel<:%08x "
"vlan>:%u vlan<:%u ether:%s <> %s", flow->flow_seq, addr1,
ntohs (flow->port[0]), addr2, ntohs (flow->port[1]),
(int) flow->protocol, flow->octets[0], flow->packets[0],
flow->octets[1], flow->packets[1], start_time,
(long long) ((flow->flow_start.tv_usec + 500) / 1000), fin_time,
(long long) ((flow->flow_last.tv_usec + 500) / 1000),
flow->tcp_flags[0], flow->tcp_flags[1], flow->ip6_flowlabel[0],
flow->ip6_flowlabel[1], flow->vlanid[0], flow->vlanid[1],
format_ethermac (flow->ethermac[0]),
format_ethermac (flow->ethermac[1]));
return (buf);
}
/* Format a flow in a brief way */
static const char *
format_flow_brief (struct FLOW *flow) {
char addr1[64], addr2[64];
static char buf[4096];
inet_ntop (flow->af, &flow->addr[0], addr1, sizeof (addr1));
inet_ntop (flow->af, &flow->addr[1], addr2, sizeof (addr2));
snprintf (buf, sizeof (buf),
"seq:%" PRIu64 " [%s]:%hu <> [%s]:%hu proto:%u "
"vlan>:%u vlan<:%u ether:%s <> %s ",
flow->flow_seq,
addr1, ntohs (flow->port[0]), addr2, ntohs (flow->port[1]),
(int) flow->protocol, flow->vlanid[0], flow->vlanid[1],
format_ethermac (flow->ethermac[0]),
format_ethermac (flow->ethermac[1]));
return (buf);
}
/* Fill in transport-layer (tcp/udp) portions of flow record */
static void
transport_to_flowrec (struct FLOW *flow, const u_int8_t * pkt,
const size_t caplen, int protocol, int ndx) {
const struct tcphdr *tcp = (const struct tcphdr *) pkt;
const struct udphdr *udp = (const struct udphdr *) pkt;
const struct icmp *icmp = (const struct icmp *) pkt;
/*
* XXX to keep flow in proper canonical format, it may be necessary to
* swap the array slots based on the order of the port numbers does
* this matter in practice??? I don't think so - return flows will
* always match, because of their symmetrical addr/ports
*/
switch (protocol) {
case IPPROTO_TCP:
/* Check for runt packet */
if (caplen < sizeof (*tcp))
return;
flow->port[ndx] = tcp->th_sport;
flow->port[ndx ^ 1] = tcp->th_dport;
flow->tcp_flags[ndx] |= tcp->th_flags;
break;
case IPPROTO_UDP:
/* Check for runt packet */
if (caplen < sizeof (*udp))
return;
flow->port[ndx] = udp->uh_sport;
flow->port[ndx ^ 1] = udp->uh_dport;
break;
case IPPROTO_ICMP:
case IPPROTO_ICMPV6:
/*
* Encode ICMP type * 256 + code into dest port like
* Cisco routers
*/
flow->port[ndx] = 0;
flow->port[ndx ^ 1] = htons (icmp->icmp_type * 256 + icmp->icmp_code);
break;
}
return;
}
/**
* @fn ipv4_to_flowrec converts a IPv4 packet to a partial flow record (used for comparison)
* @return return header size as posive value, return negative value when error occured
*/
static int
ipv4_to_flowrec (struct FLOW *flow, const u_int8_t * pkt, size_t caplen,
int *isfrag, int *isfirst, int *ndx, int track_lv) {
const struct ip *ip = (const struct ip *) pkt;
if (flow == NULL || ip == NULL || isfrag == NULL || isfirst == NULL
|| ndx == NULL || caplen < 20 || caplen < ip->ip_hl * 4
|| ip->ip_v != 4)
return (-1); /* Runt packet or Unsupported IP version */
/* Prepare to store flow in canonical format */
*ndx = memcmp (&ip->ip_src, &ip->ip_dst, sizeof (ip->ip_src)) > 0 ? 1 : 0;
flow->addr[*ndx].v4 = ip->ip_src;
flow->addr[*ndx ^ 1].v4 = ip->ip_dst;
flow->protocol = track_lv >= TRACK_IP_PROTO ? ip->ip_p : 0;
flow->tos[*ndx] = track_lv >= TRACK_FULL ? ip->ip_tos : 0;
*isfrag = (ntohs (ip->ip_off) & (IP_OFFMASK | IP_MF)) ? 1 : 0;
*isfirst = (ntohs (ip->ip_off) & IP_OFFMASK) == 0 ? 1 : 0;
return (ip->ip_hl * 4);
}
/**
* @fn ipv6_to_flowrec converts a IPv6 packet to a partial flow record (used for comparison)
* @return return header size as posive value, return negative value when error occured
*/
static int
ipv6_to_flowrec (struct FLOW *flow, const u_int8_t * pkt, size_t caplen,
int *isfrag, int *isfirst, int *ndx, int track_lv) {
const struct ip6_hdr *ip6 = (const struct ip6_hdr *) pkt;
const struct ip6_ext *eh6;
const struct ip6_frag *fh6;
int nxt, size, remain;
if (flow == NULL || ip6 == NULL || isfrag == NULL || isfirst == NULL
|| ndx == NULL || caplen < sizeof (*ip6)
|| (ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION)
return (-1); /* Runt packet or Unsupported IP version */
*ndx =
memcmp (&ip6->ip6_src, &ip6->ip6_dst, sizeof (ip6->ip6_src)) > 0 ? 1 : 0;
flow->ip6_flowlabel[*ndx] = ip6->ip6_flow & IPV6_FLOWLABEL_MASK;
flow->addr[*ndx].v6 = ip6->ip6_src;
flow->addr[*ndx ^ 1].v6 = ip6->ip6_dst;
*isfrag = 0;
*isfirst = 1;
nxt = ip6->ip6_nxt;
size = sizeof (*ip6);
/* Now loop through headers, looking for transport header */
for (;;) {
remain = caplen - size;
eh6 = (const struct ip6_ext *) pkt + size;
if (nxt == IPPROTO_HOPOPTS ||
nxt == IPPROTO_ROUTING || nxt == IPPROTO_DSTOPTS) {
int eh6size = remain < sizeof (*eh6) ? 0 : (eh6->ip6e_len + 1) << 3;
if (remain < eh6size)
return (size); /* Runt */
nxt = eh6->ip6e_nxt;
size += eh6size;
} else if (nxt == IPPROTO_FRAGMENT) {
*isfrag = 1;
fh6 = (const struct ip6_frag *) eh6;
if (remain < sizeof (*fh6))
return (size); /* Runt */
if ((fh6->ip6f_offlg & IP6F_OFF_MASK) != 0)
*isfirst = 0;
nxt = fh6->ip6f_nxt;
size += sizeof (*fh6);
} else
break;
}
flow->protocol = track_lv >= TRACK_IP_PROTO ? nxt : 0;
flow->tos[*ndx] =
track_lv >=
TRACK_FULL ? (ntohl (ip6->ip6_flow) & ntohl (0x0ff00000)) >> 20 : 0;
return size;
}
static void
ether_to_flowrec (struct FLOW *flow, const struct ether_header *ether,
int ndx) {
if (ndx < 0 || ether == NULL)
return;
memcpy (flow->ethermac[ndx], ether->ether_shost, ETH_ALEN);
memcpy (flow->ethermac[ndx ^ 1], ether->ether_dhost, ETH_ALEN);
return;
}
static void
flow_update_expiry (struct FLOWTRACK *ft, struct FLOW *flow) {
EXPIRY_REMOVE (EXPIRIES, &ft->expiries, flow->expiry);
/* Flows over 2 GiB traffic */
if (flow->octets[0] > (1U << 31) || flow->octets[1] > (1U << 31)) {
flow->expiry->expires_at = 0;
flow->expiry->reason = R_OVERBYTES;
flow->flowEndReason = IPFIX_flowEndReason_lackOfResource;
goto out;
}
/* Flows over maximum life seconds */
if (ft->param.maximum_lifetime != 0 &&
flow->flow_last.tv_sec - flow->flow_start.tv_sec >
ft->param.maximum_lifetime) {
flow->expiry->expires_at = 0;
flow->expiry->reason = R_MAXLIFE;
flow->flowEndReason = IPFIX_flowEndReason_activeTimeout;
goto out;
}
if (flow->protocol == IPPROTO_TCP) {
/* Reset TCP flows */
if (ft->param.tcp_rst_timeout != 0 &&
((flow->tcp_flags[0] & TH_RST) || (flow->tcp_flags[1] & TH_RST))) {
flow->expiry->expires_at = flow->flow_last.tv_sec +
ft->param.tcp_rst_timeout;
flow->expiry->reason = R_TCP_RST;
flow->flowEndReason = IPFIX_flowEndReason_endOfFlow;
goto out;
}
/* Finished TCP flows */
if (ft->param.tcp_fin_timeout != 0 &&
((flow->tcp_flags[0] & TH_FIN) && (flow->tcp_flags[1] & TH_FIN))) {
flow->expiry->expires_at = flow->flow_last.tv_sec +
ft->param.tcp_fin_timeout;
flow->expiry->reason = R_TCP_FIN;
flow->flowEndReason = IPFIX_flowEndReason_endOfFlow;
goto out;
}
/* TCP flows */
if (ft->param.tcp_timeout != 0) {
flow->expiry->expires_at = flow->flow_last.tv_sec +
ft->param.tcp_timeout;
flow->expiry->reason = R_TCP;
flow->flowEndReason = IPFIX_flowEndReason_idleTimeout;
goto out;
}
}
if (ft->param.udp_timeout != 0 && flow->protocol == IPPROTO_UDP) {
/* UDP flows */
flow->expiry->expires_at = flow->flow_last.tv_sec + ft->param.udp_timeout;
flow->expiry->reason = R_UDP;
flow->flowEndReason = IPFIX_flowEndReason_idleTimeout;
goto out;
}
if (ft->param.icmp_timeout != 0 &&
((flow->af == AF_INET && flow->protocol == IPPROTO_ICMP) ||
((flow->af == AF_INET6 && flow->protocol == IPPROTO_ICMPV6)))) {
/* ICMP flows */
flow->expiry->expires_at = flow->flow_last.tv_sec +
ft->param.icmp_timeout;
flow->expiry->reason = R_ICMP;
flow->flowEndReason = IPFIX_flowEndReason_idleTimeout;
goto out;
}
/* Everything else */
flow->expiry->expires_at = flow->flow_last.tv_sec +
ft->param.general_timeout;
flow->expiry->reason = R_GENERAL;
flow->flowEndReason = IPFIX_flowEndReason_idleTimeout;
out:
if (ft->param.maximum_lifetime != 0 && flow->expiry->expires_at != 0) {
flow->expiry->expires_at = MIN (flow->expiry->expires_at,
flow->flow_start.tv_sec +
ft->param.maximum_lifetime);
}
EXPIRY_INSERT (EXPIRIES, &ft->expiries, flow->expiry);
}
/* Return values from process_packet */
#define PP_OK 0
#define PP_BAD_PACKET -2
#define PP_MALLOC_FAIL -3
/*
* Main per-packet processing function. Take a packet (provided by
* libpcap) and attempt to find a matching flow. If no such flow exists,
* then create one.
*
* Also marks flows for fast expiry, based on flow or packet attributes
* (the actual expiry is performed elsewhere)
*/
static int
process_packet (struct CB_CTXT *cb_ctxt, const struct pcap_pkthdr *phdr,
const u_char * frame, int datalink_size, int af,
u_int16_t vlanid, u_int8_t num_label) {
struct FLOW tmp, *flow;
struct FLOWTRACK *ft = cb_ctxt->ft;
const u_int32_t caplen = phdr->caplen - datalink_size;
int frag = 0, first = 1, ndx = -1, i = 0, size = -1;
const u_int8_t *pkt = frame + datalink_size + num_label * 4;
/* Convert the IP packet to a flow identity */
memset (&tmp, 0, sizeof (tmp));
if (af == AF_INET) {
size =
ipv4_to_flowrec (&tmp, pkt, caplen, &frag, &first, &ndx,
ft->param.track_level);
} else if (af == AF_INET6) {
size =
ipv6_to_flowrec (&tmp, pkt, caplen, &frag, &first, &ndx,
ft->param.track_level);
}
if ((af != AF_INET && af != AF_INET6) || ndx < 0 || size == -1) { /* bad packet */
ft->param.bad_packets++;
return (PP_BAD_PACKET);
}
/* good packet */
tmp.af = af;
tmp.octets[ndx] = phdr->len - datalink_size;
tmp.packets[ndx] = 1;
if (frag)
ft->param.frag_packets++;
if (first && ft->param.track_level >= TRACK_IP_PROTO_PORT)
transport_to_flowrec (&tmp, pkt + size, caplen - size, tmp.protocol, ndx);
if (ft->param.track_level >= TRACK_FULL_VLAN)
tmp.vlanid[ndx] = vlanid;
if (ft->param.track_level >= TRACK_FULL_VLAN_ETHER
&& cb_ctxt->linktype == DLT_EN10MB)
ether_to_flowrec (&tmp, (const struct ether_header *) frame, ndx);
tmp.mplsLabelStackDepth = num_label;
for (i = 0; i < num_label && i < 10; i++) {
tmp.mplsLabels[i] = *(((const u_int32_t *) (frame + datalink_size)) + i);
}
/* If a matching flow does not exist, create and insert one */
if ((flow = FLOW_FIND (FLOWS, &ft->flows, &tmp)) == NULL) {
/* Allocate and fill in the flow */
if ((flow = flow_get (ft)) == NULL) {
logit (LOG_ERR, "process_packet: flow_get failed", sizeof (*flow));
return (PP_MALLOC_FAIL);
}
memcpy (flow, &tmp, sizeof (*flow));
memcpy (&flow->flow_start, &phdr->ts, sizeof (flow->flow_start));
flow->flow_seq = ft->param.next_flow_seq++;
FLOW_INSERT (FLOWS, &ft->flows, flow);
/* Allocate and fill in the associated expiry event */
if ((flow->expiry = expiry_get (ft)) == NULL) {
logit (LOG_ERR, "process_packet: expiry_get failed",
sizeof (*flow->expiry));
return (PP_MALLOC_FAIL);
}
flow->expiry->flow = flow;
/* Must be non-zero (0 means expire immediately) */
flow->expiry->expires_at = 1;
flow->expiry->reason = R_GENERAL;
flow->flowEndReason = IPFIX_flowEndReason_idleTimeout;
EXPIRY_INSERT (EXPIRIES, &ft->expiries, flow->expiry);
ft->param.num_flows++;
if (verbose_flag)
logit (LOG_DEBUG, "ADD FLOW %s", format_flow_brief (flow));
} else {
/* Update flow statistics */
flow->packets[0] += tmp.packets[0];
flow->octets[0] += tmp.octets[0];
flow->tcp_flags[0] |= tmp.tcp_flags[0];
flow->packets[1] += tmp.packets[1];
flow->octets[1] += tmp.octets[1];
flow->tcp_flags[1] |= tmp.tcp_flags[1];
}
memcpy (&flow->flow_last, &phdr->ts, sizeof (flow->flow_last));
if (flow->expiry->expires_at != 0)
flow_update_expiry (ft, flow);
return (PP_OK);
}
/*
* Subtract two timevals. Returns (t1 - t2) in milliseconds.
*/
u_int32_t
timeval_sub_ms (const struct timeval *t1, const struct timeval *t2) {
struct timeval res;
res.tv_sec = t1->tv_sec - t2->tv_sec;
res.tv_usec = t1->tv_usec - t2->tv_usec;
if (res.tv_usec < 0) {
res.tv_usec += 1000000L;
res.tv_sec--;
}
return ((u_int32_t) res.tv_sec * 1000 + (u_int32_t) res.tv_usec / 1000);
}
int
send_multi_destinations (int num_destinations,
struct DESTINATION *destinations,
u_int8_t is_loadbalance, u_int8_t * packet,
int size) {
struct DESTINATION *dest;
int i, err;
socklen_t errsz;
static u_int64_t sent = 0;
for (i = 0; i < num_destinations; i++) {
if (!is_loadbalance || (is_loadbalance && (sent % num_destinations == i))) {
dest = &destinations[i];
errsz = sizeof (err);
getsockopt (dest->sock, SOL_SOCKET, SO_ERROR, &err, &errsz); // Clear ICMP errors
if (send (dest->sock, packet, (size_t) size, 0) == -1)
return (-1);
}
}
sent++;
return is_loadbalance ? 1 : i;
}
static void
update_statistic (struct STATISTIC *s, double new, double n) {
if (n == 1.0) {
s->min = s->mean = s->max = new;
return;
}
s->min = MIN (s->min, new);
s->max = MAX (s->max, new);
s->mean = s->mean + ((new - s->mean) / n);
}
/* Update global statistics */
static void
update_statistics (struct FLOWTRACK *ft, struct FLOW *flow) {
double tmp;
static double n = 1.0;
ft->param.flows_expired++;
ft->param.flows_pp[flow->protocol % 256]++;
tmp = (double) flow->flow_last.tv_sec +
((double) flow->flow_last.tv_usec / 1000000.0);
tmp -= (double) flow->flow_start.tv_sec +
((double) flow->flow_start.tv_usec / 1000000.0);
if (tmp < 0.0)
tmp = 0.0;
update_statistic (&ft->param.duration, tmp, n);
update_statistic (&ft->param.duration_pp[flow->protocol], tmp,
(double) ft->param.flows_pp[flow->protocol % 256]);
tmp = flow->octets[0] + flow->octets[1];
update_statistic (&ft->param.octets, tmp, n);
ft->param.octets_pp[flow->protocol % 256] += tmp;
tmp = flow->packets[0] + flow->packets[1];
update_statistic (&ft->param.packets, tmp, n);
ft->param.packets_pp[flow->protocol % 256] += tmp;
n++;
}
static void
update_expiry_stats (struct FLOWTRACK *ft, struct EXPIRY *e) {
switch (e->reason) {
case R_GENERAL:
ft->param.expired_general++;
break;
case R_TCP:
ft->param.expired_tcp++;
break;
case R_TCP_RST:
ft->param.expired_tcp_rst++;
break;
case R_TCP_FIN:
ft->param.expired_tcp_fin++;
break;
case R_UDP:
ft->param.expired_udp++;
break;
case R_ICMP:
ft->param.expired_icmp++;
break;
case R_MAXLIFE:
ft->param.expired_maxlife++;
break;
case R_OVERBYTES:
ft->param.expired_overbytes++;
break;
case R_OVERFLOWS:
ft->param.expired_maxflows++;
break;
case R_FLUSH:
ft->param.expired_flush++;
break;
}
}
/* How long before the next expiry event in millisecond */
static int
next_expire (struct FLOWTRACK *ft) {
struct EXPIRY *expiry;
struct timeval now;
u_int32_t expires_at, ret, fudge;
if (ft->param.adjust_time)
now = ft->param.last_packet_time;
else
gettimeofday (&now, NULL);
if ((expiry = EXPIRY_MIN (EXPIRIES, &ft->expiries)) == NULL)
return (-1); /* indefinite */
expires_at = expiry->expires_at;
/* Don't cluster urgent expiries */
if (expires_at == 0 && (expiry->reason == R_OVERBYTES ||
expiry->reason == R_OVERFLOWS
|| expiry->reason == R_FLUSH))
return (0); /* Now */
/* Cluster expiries by expiry_interval */
if (ft->param.expiry_interval > 1) {
if ((fudge = expires_at % ft->param.expiry_interval) > 0)
expires_at += ft->param.expiry_interval - fudge;
}
if (expires_at < now.tv_sec)
return (0); /* Now */
ret = 999 + (expires_at - now.tv_sec) * 1000;
return (ret);
}
/*
* Scan the tree of expiry events and process expired flows. If zap_all
* is set, then forcibly expire all flows.
*/
#define CE_EXPIRE_NORMAL 0 /* Normal expiry processing */
#define CE_EXPIRE_ALL -1 /* Expire all flows immediately */
#define CE_EXPIRE_FORCED 1 /* Only expire force-expired flows */
static int
check_expired (struct FLOWTRACK *ft, struct NETFLOW_TARGET *target, int ex) {
struct FLOW **expired_flows, **oldexp;
int num_expired, i, r;
struct timeval now;
struct EXPIRY *expiry, *nexpiry;
if (ft->param.adjust_time)
now = ft->param.last_packet_time;
else
gettimeofday (&now, NULL);
r = 0;
num_expired = 0;
expired_flows = NULL;
if (verbose_flag)
logit (LOG_DEBUG, "Starting expiry scan: mode %d", ex);
for (expiry = EXPIRY_MIN (EXPIRIES, &ft->expiries);
expiry != NULL; expiry = nexpiry) {
nexpiry = EXPIRY_NEXT (EXPIRIES, &ft->expiries, expiry);
if ((expiry->expires_at == 0) || (ex == CE_EXPIRE_ALL) ||
(ex != CE_EXPIRE_FORCED && (expiry->expires_at < now.tv_sec))) {
/* Flow has expired */
if (ft->param.maximum_lifetime != 0 &&
expiry->flow->flow_last.tv_sec -
expiry->flow->flow_start.tv_sec >= ft->param.maximum_lifetime)
expiry->reason = R_MAXLIFE;
if (verbose_flag)
logit (LOG_DEBUG,
"Queuing flow seq:%" PRIu64 " (%p) for expiry "
"reason %d", expiry->flow->flow_seq,
expiry->flow, expiry->reason);
/* Add to array of expired flows */
oldexp = expired_flows;
expired_flows = realloc (expired_flows,
sizeof (*expired_flows) * (num_expired + 1));
/* Don't fatal on realloc failures */
if (expired_flows == NULL)
expired_flows = oldexp;
else {
expired_flows[num_expired] = expiry->flow;
num_expired++;
}
if (ex == CE_EXPIRE_ALL)
expiry->reason = R_FLUSH;
update_expiry_stats (ft, expiry);
/* Remove from flow tree, destroy expiry event */
FLOW_REMOVE (FLOWS, &ft->flows, expiry->flow);
EXPIRY_REMOVE (EXPIRIES, &ft->expiries, expiry);
expiry->flow->expiry = NULL;
expiry_put (ft, expiry);
ft->param.num_flows--;
}
}
if (verbose_flag)
logit (LOG_DEBUG, "Finished scan %d flow(s) to be evicted", num_expired);
/* Processing for expired flows */
if (num_expired > 0) {
if (target != NULL) {
struct SENDPARAMETER sp =
{ expired_flows, num_expired, target, if_index, &ft->param,
verbose_flag
};
netflow_send_func_t *func =
ft->param.bidirection ==
1 ? target->dialect->bidir_func : target->dialect->func;
if (func == NULL) {
func = target->dialect->func;
}
#ifdef ENABLE_PTHREAD
if (use_thread) {
pthread_t write_thread = 0;
sp.flows = calloc (num_expired, sizeof (struct FLOW));
memcpy (sp.flows, expired_flows, sizeof (struct FLOW) * num_expired);
if (pthread_create (&write_thread, NULL, (void *) func, (void *) &sp)
< 0) {
perror ("pthread_create error");
exit (1);
}
if (pthread_detach (write_thread) != 0) {
perror ("pthread_detach error");
exit (1);
}
r = 1;
} else
#endif /* ENABLE_PTHREAD */
r = func (sp);
if (verbose_flag)
logit (LOG_DEBUG, "sent %d netflow packets", r);
if (r <= 0)
ft->param.flows_dropped += num_expired * 2; /* XXX what if r < num_expired * 2 ? */
}
for (i = 0; i < num_expired; i++) {
if (verbose_flag) {
logit (LOG_DEBUG, "EXPIRED: %s (%p)",
format_flow (expired_flows[i]), expired_flows[i]);
}
update_statistics (ft, expired_flows[i]);
flow_put (ft, expired_flows[i]);
}
free (expired_flows);
}
if (ft->param.boot_time_reinit != 0) {
if (now.tv_sec - ft->param.system_boot_time.tv_sec >
ft->param.boot_time_reinit) {
ft->param.system_boot_time = now;
}
}
return (r == -1 ? -1 : num_expired);
}
/*
* Force expiry of num_to_expire flows (e.g. when flow table overfull)
*/
static void
force_expire (struct FLOWTRACK *ft, u_int32_t num_to_expire) {
struct EXPIRY *expiry, **expiryv;
int i;
/* XXX move all overflow processing here (maybe) */
if (verbose_flag)
logit (LOG_INFO, "Forcing expiry of %d flows", num_to_expire);
/*
* Do this in two steps, as it is dangerous to change a key on
* a tree entry without first removing it and then re-adding it.
* It is even worse when this has to be done during a FOREACH :)
* To get around this, we make a list of expired flows and _then_
* alter them
*/
if ((expiryv = calloc (num_to_expire, sizeof (*expiryv))) == NULL) {
/*
* On malloc failure, expire ALL flows. I assume that
* setting all the keys in a tree to the same value is
* safe.
*/
logit (LOG_ERR, "Out of memory while expiring flows - "
"all flows expired");
EXPIRY_FOREACH (expiry, EXPIRIES, &ft->expiries) {
expiry->expires_at = 0;
expiry->reason = R_OVERFLOWS;
ft->param.flows_force_expired++;
}
return;