1 files changed, 762 insertions, 0 deletions

diff --git a/contrib/libpcap/pcap-dag.c b/contrib/libpcap/pcap-dag.c
new file mode 100644
index 0000000..a30f970
--- /dev/null
+++ b/contrib/libpcap/pcap-dag.c
@@ -0,0 +1,762 @@
+/*
+ * pcap-dag.c: Packet capture interface for Endace DAG card.
+ *
+ * The functionality of this code attempts to mimic that of pcap-linux as much
+ * as possible.  This code is compiled in several different ways depending on
+ * whether DAG_ONLY and HAVE_DAG_API are defined.  If HAVE_DAG_API is not
+ * defined it should not get compiled in, otherwise if DAG_ONLY is defined then
+ * the 'dag_' function calls are renamed to 'pcap_' equivalents.  If DAG_ONLY
+ * is not defined then nothing is altered - the dag_ functions will be
+ * called as required from their pcap-linux/bpf equivalents.
+ *
+ * Authors: Richard Littin, Sean Irvine ({richard,sean}@reeltwo.com)
+ * Modifications: Jesper Peterson, Koryn Grant <support@endace.com>
+ */
+
+#ifndef lint
+static const char rcsid[] _U_ =
+	"@(#) $Header: /tcpdump/master/libpcap/pcap-dag.c,v 1.21 2005/04/03 23:56:47 guy Exp $ (LBL)";
+#endif
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <sys/param.h>			/* optionally get BSD define */
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include "pcap-int.h"
+
+#include <ctype.h>
+#include <netinet/in.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+struct mbuf;		/* Squelch compiler warnings on some platforms for */
+struct rtentry;		/* declarations in <net/if.h> */
+#include <net/if.h>
+
+#include "dagnew.h"
+#include "dagapi.h"
+
+#define MIN_DAG_SNAPLEN		12
+#define MAX_DAG_SNAPLEN		2040
+#define ATM_CELL_SIZE		52
+#define ATM_HDR_SIZE		4
+
+/* SunATM pseudo header */
+struct sunatm_hdr {
+	unsigned char	flags;		/* destination and traffic type */
+	unsigned char	vpi;		/* VPI */
+	unsigned short	vci;		/* VCI */
+};
+
+typedef struct pcap_dag_node {
+	struct pcap_dag_node *next;
+	pcap_t *p;
+	pid_t pid;
+} pcap_dag_node_t;
+
+static pcap_dag_node_t *pcap_dags = NULL;
+static int atexit_handler_installed = 0;
+static const unsigned short endian_test_word = 0x0100;
+
+#define IS_BIGENDIAN() (*((unsigned char *)&endian_test_word))
+
+/*
+ * Swap byte ordering of unsigned long long timestamp on a big endian
+ * machine.
+ */
+#define SWAP_TS(ull)  ((ull & 0xff00000000000000LL) >> 56) | \
+                      ((ull & 0x00ff000000000000LL) >> 40) | \
+                      ((ull & 0x0000ff0000000000LL) >> 24) | \
+                      ((ull & 0x000000ff00000000LL) >> 8)  | \
+                      ((ull & 0x00000000ff000000LL) << 8)  | \
+                      ((ull & 0x0000000000ff0000LL) << 24) | \
+                      ((ull & 0x000000000000ff00LL) << 40) | \
+                      ((ull & 0x00000000000000ffLL) << 56)
+
+
+#ifdef DAG_ONLY
+/* This code is required when compiling for a DAG device only. */
+#include "pcap-dag.h"
+
+/* Replace dag function names with pcap equivalent. */
+#define dag_open_live pcap_open_live
+#define dag_platform_finddevs pcap_platform_finddevs
+#endif /* DAG_ONLY */
+
+static int dag_setfilter(pcap_t *p, struct bpf_program *fp);
+static int dag_stats(pcap_t *p, struct pcap_stat *ps);
+static int dag_set_datalink(pcap_t *p, int dlt);
+static int dag_get_datalink(pcap_t *p);
+static int dag_setnonblock(pcap_t *p, int nonblock, char *errbuf);
+
+static void
+delete_pcap_dag(pcap_t *p)
+{
+	pcap_dag_node_t *curr = NULL, *prev = NULL;
+
+	for (prev = NULL, curr = pcap_dags; curr != NULL && curr->p != p; prev = curr, curr = curr->next) {
+		/* empty */
+	}
+
+	if (curr != NULL && curr->p == p) {
+		if (prev != NULL) {
+			prev->next = curr->next;
+		} else {
+			pcap_dags = curr->next;
+		}
+	}
+}
+
+/*
+ * Performs a graceful shutdown of the DAG card, frees dynamic memory held
+ * in the pcap_t structure, and closes the file descriptor for the DAG card.
+ */
+
+static void
+dag_platform_close(pcap_t *p)
+{
+
+#ifdef linux
+	if (p != NULL && p->md.device != NULL) {
+		if(dag_stop(p->fd) < 0)
+			fprintf(stderr,"dag_stop %s: %s\n", p->md.device, strerror(errno));
+		if(dag_close(p->fd) < 0)
+			fprintf(stderr,"dag_close %s: %s\n", p->md.device, strerror(errno));
+		
+		free(p->md.device);
+	}
+#else
+	if (p != NULL) {
+		if(dag_stop(p->fd) < 0)
+			fprintf(stderr,"dag_stop: %s\n", strerror(errno));
+		if(dag_close(p->fd) < 0)
+			fprintf(stderr,"dag_close: %s\n", strerror(errno));
+	}
+#endif
+	delete_pcap_dag(p);
+	/* Note: don't need to call close(p->fd) here as dag_close(p->fd) does this. */
+}
+
+static void
+atexit_handler(void)
+{
+	while (pcap_dags != NULL) {
+		if (pcap_dags->pid == getpid()) {
+			dag_platform_close(pcap_dags->p);
+		} else {
+			delete_pcap_dag(pcap_dags->p);
+		}
+	}
+}
+
+static int
+new_pcap_dag(pcap_t *p)
+{
+	pcap_dag_node_t *node = NULL;
+
+	if ((node = malloc(sizeof(pcap_dag_node_t))) == NULL) {
+		return -1;
+	}
+
+	if (!atexit_handler_installed) {
+		atexit(atexit_handler);
+		atexit_handler_installed = 1;
+	}
+
+	node->next = pcap_dags;
+	node->p = p;
+	node->pid = getpid();
+
+	pcap_dags = node;
+
+	return 0;
+}
+
+/*
+ *  Read at most max_packets from the capture stream and call the callback
+ *  for each of them. Returns the number of packets handled, -1 if an
+ *  error occured, or -2 if we were told to break out of the loop.
+ */
+static int
+dag_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
+{
+	unsigned int processed = 0;
+	int flags = p->md.dag_offset_flags;
+	unsigned int nonblocking = flags & DAGF_NONBLOCK;
+
+	for (;;)
+	{
+		/* Get the next bufferful of packets (if necessary). */
+		while (p->md.dag_mem_top - p->md.dag_mem_bottom < dag_record_size) {
+ 
+			/*
+			 * Has "pcap_breakloop()" been called?
+			 */
+			if (p->break_loop) {
+				/*
+				 * Yes - clear the flag that indicates that
+				 * it has, and return -2 to indicate that
+				 * we were told to break out of the loop.
+				 */
+				p->break_loop = 0;
+				return -2;
+			}
+
+			p->md.dag_mem_top = dag_offset(p->fd, &(p->md.dag_mem_bottom), flags);
+			if (nonblocking && (p->md.dag_mem_top - p->md.dag_mem_bottom < dag_record_size))
+			{
+				/* Pcap is configured to process only available packets, and there aren't any. */
+				return 0;
+			}
+		}
+	
+		/* Process the packets. */
+		while (p->md.dag_mem_top - p->md.dag_mem_bottom >= dag_record_size) {
+
+			unsigned short packet_len = 0;
+			int caplen = 0;
+			struct pcap_pkthdr	pcap_header;
+
+			dag_record_t *header = (dag_record_t *)(p->md.dag_mem_base + p->md.dag_mem_bottom);
+			u_char *dp = ((u_char *)header) + dag_record_size;
+			unsigned short rlen;
+ 
+			/*
+			 * Has "pcap_breakloop()" been called?
+			 */
+			if (p->break_loop) {
+				/*
+				 * Yes - clear the flag that indicates that
+				 * it has, and return -2 to indicate that
+				 * we were told to break out of the loop.
+				 */
+				p->break_loop = 0;
+				return -2;
+			}
+ 
+				rlen = ntohs(header->rlen);
+			if (rlen < dag_record_size)
+			{
+				strncpy(p->errbuf, "dag_read: record too small", PCAP_ERRBUF_SIZE);
+				return -1;
+			}
+			p->md.dag_mem_bottom += rlen;
+
+			switch(header->type) {
+			case TYPE_AAL5:
+			case TYPE_ATM:
+				if (header->type == TYPE_AAL5) {
+						packet_len = ntohs(header->wlen);
+					caplen = rlen - dag_record_size;
+				} else {
+					caplen = packet_len = ATM_CELL_SIZE;
+				}
+				if (p->linktype == DLT_SUNATM) {
+					struct sunatm_hdr *sunatm = (struct sunatm_hdr *)dp;
+					unsigned long rawatm;
+					
+						rawatm = ntohl(*((unsigned long *)dp));
+						sunatm->vci = htons((rawatm >>  4) & 0xffff);
+					sunatm->vpi = (rawatm >> 20) & 0x00ff;
+					sunatm->flags = ((header->flags.iface & 1) ? 0x80 : 0x00) | 
+						((sunatm->vpi == 0 && sunatm->vci == htons(5)) ? 6 :
+						((sunatm->vpi == 0 && sunatm->vci == htons(16)) ? 5 : 
+						((dp[ATM_HDR_SIZE] == 0xaa &&
+							dp[ATM_HDR_SIZE+1] == 0xaa &&
+							dp[ATM_HDR_SIZE+2] == 0x03) ? 2 : 1)));
+
+				} else {
+					packet_len -= ATM_HDR_SIZE;
+					caplen -= ATM_HDR_SIZE;
+					dp += ATM_HDR_SIZE;
+				}
+				break;
+
+			case TYPE_ETH:
+					packet_len = ntohs(header->wlen);
+				packet_len -= (p->md.dag_fcs_bits >> 3);
+				caplen = rlen - dag_record_size - 2;
+				if (caplen > packet_len) {
+					caplen = packet_len;
+				}
+				dp += 2;
+				break;
+
+			case TYPE_HDLC_POS:
+					packet_len = ntohs(header->wlen);
+				packet_len -= (p->md.dag_fcs_bits >> 3);
+				caplen = rlen - dag_record_size;
+				if (caplen > packet_len) {
+					caplen = packet_len;
+				}
+				break;
+			}
+ 
+			if (caplen > p->snapshot)
+				caplen = p->snapshot;
+
+			/* Count lost packets. */
+			if (header->lctr) {
+				if (p->md.stat.ps_drop > (UINT_MAX - ntohs(header->lctr))) {
+					p->md.stat.ps_drop = UINT_MAX;
+				} else {
+					p->md.stat.ps_drop += ntohs(header->lctr);
+				}
+			}
+
+			/* Run the packet filter if there is one. */
+			if ((p->fcode.bf_insns == NULL) || bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
+
+				/* convert between timestamp formats */
+				register unsigned long long ts;
+				
+				if (IS_BIGENDIAN()) {
+					ts = SWAP_TS(header->ts);
+				} else {
+					ts = header->ts;
+				}
+
+				pcap_header.ts.tv_sec = ts >> 32;
+				ts = (ts & 0xffffffffULL) * 1000000;
+				ts += 0x80000000; /* rounding */
+				pcap_header.ts.tv_usec = ts >> 32;		
+				if (pcap_header.ts.tv_usec >= 1000000) {
+					pcap_header.ts.tv_usec -= 1000000;
+					pcap_header.ts.tv_sec++;
+				}
+
+				/* Fill in our own header data */
+				pcap_header.caplen = caplen;
+				pcap_header.len = packet_len;
+	
+				/* Count the packet. */
+				p->md.stat.ps_recv++;
+	
+				/* Call the user supplied callback function */
+				callback(user, &pcap_header, dp);
+	
+				/* Only count packets that pass the filter, for consistency with standard Linux behaviour. */
+				processed++;
+				if (processed == cnt)
+				{
+					/* Reached the user-specified limit. */
+					return cnt;
+				}
+			}
+		}
+
+		if (nonblocking || processed)
+		{
+			return processed;
+		}
+	}
+	
+	return processed;
+}
+
+static int
+dag_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
+{
+	strlcpy(p->errbuf, "Sending packets isn't supported on DAG cards",
+	    PCAP_ERRBUF_SIZE);
+	return (-1);
+}
+
+/*
+ *  Get a handle for a live capture from the given DAG device.  Passing a NULL
+ *  device will result in a failure.  The promisc flag is ignored because DAG
+ *  cards are always promiscuous.  The to_ms parameter is also ignored as it is
+ *  not supported in hardware.
+ *  
+ *  See also pcap(3).
+ */
+pcap_t *
+dag_open_live(const char *device, int snaplen, int promisc, int to_ms, char *ebuf)
+{
+	char conf[30]; /* dag configure string */
+	pcap_t *handle;
+	char *s;
+	int n;
+	daginf_t* daginf;
+	
+	if (device == NULL) {
+		snprintf(ebuf, PCAP_ERRBUF_SIZE, "device is NULL: %s", pcap_strerror(errno));
+		return NULL;
+	}
+	/* Allocate a handle for this session. */
+
+	handle = malloc(sizeof(*handle));
+	if (handle == NULL) {
+		snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc %s: %s", device, pcap_strerror(errno));
+		return NULL;
+	}
+	
+	/* Initialize some components of the pcap structure. */
+	
+	memset(handle, 0, sizeof(*handle));
+
+	if (strstr(device, "/dev") == NULL) {
+		char * newDev = (char *)malloc(strlen(device) + 6);
+		newDev[0] = '\0';
+		strcat(newDev, "/dev/");
+		strcat(newDev,device);
+		device = newDev;
+	} else {
+		device = strdup(device);
+	}
+
+	if (device == NULL) {
+		snprintf(ebuf, PCAP_ERRBUF_SIZE, "str_dup: %s\n", pcap_strerror(errno));
+		goto fail;
+	}
+
+	/* setup device parameters */
+	if((handle->fd = dag_open((char *)device)) < 0) {
+		snprintf(ebuf, PCAP_ERRBUF_SIZE, "dag_open %s: %s", device, pcap_strerror(errno));
+		goto fail;
+	}
+
+	/* set the card snap length to the specified snaplen parameter */
+	if (snaplen == 0 || snaplen > MAX_DAG_SNAPLEN) {
+		snaplen = MAX_DAG_SNAPLEN;
+	} else if (snaplen < MIN_DAG_SNAPLEN) {
+		snaplen = MIN_DAG_SNAPLEN;
+	}
+	/* snap len has to be a multiple of 4 */
+	snprintf(conf, 30, "varlen slen=%d", (snaplen + 3) & ~3); 
+
+	if(dag_configure(handle->fd, conf) < 0) {
+		snprintf(ebuf, PCAP_ERRBUF_SIZE,"dag_configure %s: %s\n", device, pcap_strerror(errno));
+		goto fail;
+	}
+	
+	if((handle->md.dag_mem_base = dag_mmap(handle->fd)) == MAP_FAILED) {
+		snprintf(ebuf, PCAP_ERRBUF_SIZE,"dag_mmap %s: %s\n", device, pcap_strerror(errno));
+		goto fail;
+	}
+	
+	if(dag_start(handle->fd) < 0) {
+		snprintf(ebuf, PCAP_ERRBUF_SIZE, "dag_start %s: %s\n", device, pcap_strerror(errno));
+		goto fail;
+	}
+
+	/*
+	 * Important! You have to ensure bottom is properly
+	 * initialized to zero on startup, it won't give you
+	 * a compiler warning if you make this mistake!
+	 */
+	handle->md.dag_mem_bottom = 0;
+	handle->md.dag_mem_top = 0;
+	handle->md.dag_fcs_bits = 32;
+
+	/* Query the card first for special cases. */
+	daginf = dag_info(handle->fd);
+	if ((0x4200 == daginf->device_code) || (0x4230 == daginf->device_code))
+	{
+		/* DAG 4.2S and 4.23S already strip the FCS.  Stripping the final word again truncates the packet. */
+		handle->md.dag_fcs_bits = 0;
+	}
+
+	/* Then allow an environment variable to override. */
+	if ((s = getenv("ERF_FCS_BITS")) != NULL) {
+		if ((n = atoi(s)) == 0 || n == 16|| n == 32) {
+			handle->md.dag_fcs_bits = n;
+		} else {
+			snprintf(ebuf, PCAP_ERRBUF_SIZE,
+				"pcap_open_live %s: bad ERF_FCS_BITS value (%d) in environment\n", device, n);
+			goto fail;
+		}
+	}
+
+	handle->snapshot	= snaplen;
+	/*handle->md.timeout	= to_ms; */
+
+	handle->linktype = -1;
+	if (dag_get_datalink(handle) < 0) {
+		strcpy(ebuf, handle->errbuf);
+		goto fail;
+	}
+	
+	handle->bufsize = 0;
+
+	if (new_pcap_dag(handle) < 0) {
+		snprintf(ebuf, PCAP_ERRBUF_SIZE, "new_pcap_dag %s: %s\n", device, pcap_strerror(errno));
+		goto fail;
+	}
+
+	/*
+	 * "select()" and "poll()" don't (yet) work on DAG device descriptors.
+	 */
+	handle->selectable_fd = -1;
+
+#ifdef linux
+	handle->md.device = (char *)device;
+#else
+	free((char *)device);
+	device = NULL;
+#endif
+
+	handle->read_op = dag_read;
+	handle->inject_op = dag_inject;
+	handle->setfilter_op = dag_setfilter;
+	handle->set_datalink_op = dag_set_datalink;
+	handle->getnonblock_op = pcap_getnonblock_fd;
+	handle->setnonblock_op = dag_setnonblock;
+	handle->stats_op = dag_stats;
+	handle->close_op = dag_platform_close;
+
+	return handle;
+
+fail:
+	if (device != NULL) {
+		free((char *)device);
+	}
+	if (handle != NULL) {
+		/*
+		 * Get rid of any link-layer type list we allocated.
+		 */
+		if (handle->dlt_list != NULL) {
+			free(handle->dlt_list);
+		}
+		free(handle);
+	}
+
+	return NULL;
+}
+
+static int
+dag_stats(pcap_t *p, struct pcap_stat *ps) {
+	/* This needs to be filled out correctly.  Hopefully a dagapi call will
+		 provide all necessary information.
+	*/
+	/*p->md.stat.ps_recv = 0;*/
+	/*p->md.stat.ps_drop = 0;*/
+	
+	*ps = p->md.stat;
+ 
+	return 0;
+}
+
+/*
+ * Get from "/proc/dag" all interfaces listed there; if they're
+ * already in the list of interfaces we have, that won't add another
+ * instance, but if they're not, that'll add them.
+ *
+ * We don't bother getting any addresses for them.
+ *
+ * We also don't fail if we couldn't open "/proc/dag"; we just leave
+ * the list of interfaces as is.
+ */
+int
+dag_platform_finddevs(pcap_if_t **devlistp, char *errbuf)
+{
+	FILE *proc_dag_f;
+	char linebuf[512];
+	int linenum;
+	unsigned char *p;
+	char name[512];	/* XXX - pick a size */
+	char *q;
+	int ret = 0;
+
+	/* Quick exit if /proc/dag not readable */
+	proc_dag_f = fopen("/proc/dag", "r");
+	if (proc_dag_f == NULL)
+	{
+		int i;
+		char dev[16] = "dagx";
+
+		for (i = '0'; ret == 0 && i <= '9'; i++) {
+			dev[3] = i;
+			if (pcap_add_if(devlistp, dev, 0, NULL, errbuf) == -1) {
+				/*
+				 * Failure.
+				 */
+				ret = -1;
+			}
+		}
+
+		return (ret);
+	}
+
+	for (linenum = 1; fgets(linebuf, sizeof linebuf, proc_dag_f) != NULL; linenum++) {
+		
+		/*
+		 * Skip the first two lines - they're headers.
+		 */
+		if (linenum <= 2)
+			continue;
+
+		p = &linebuf[0];
+
+		if (*p == '\0' || *p == '\n' || *p != 'D')
+			continue;  /* not a Dag line */
+
+		/*
+		 * Get the interface name.
+		 */
+		q = &name[0];
+		while (*p != '\0' && *p != ':') {
+			if (*p != ' ')
+				*q++ = tolower(*p++);
+			else
+				p++;
+		}
+		*q = '\0';
+
+		/*
+		 * Add an entry for this interface, with no addresses.
+		 */
+		p[strlen(p) - 1] = '\0'; /* get rid of \n */
+		if (pcap_add_if(devlistp, name, 0, strdup(p + 2), errbuf) == -1) {
+			/*
+			 * Failure.
+			 */
+			ret = -1;
+			break;
+		}
+	}
+	if (ret != -1) {
+		/*
+		 * Well, we didn't fail for any other reason; did we
+		 * fail due to an error reading the file?
+		 */
+		if (ferror(proc_dag_f)) {
+			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+				  "Error reading /proc/dag: %s",
+				  pcap_strerror(errno));
+			ret = -1;
+		}
+	}
+
+	(void)fclose(proc_dag_f);
+	return (ret);
+}
+
+/*
+ * Installs the given bpf filter program in the given pcap structure.  There is
+ * no attempt to store the filter in kernel memory as that is not supported
+ * with DAG cards.
+ */
+static int
+dag_setfilter(pcap_t *p, struct bpf_program *fp)
+{
+	if (!p)
+		return -1;
+	if (!fp) {
+		strncpy(p->errbuf, "setfilter: No filter specified",
+			sizeof(p->errbuf));
+		return -1;
+	}
+
+	/* Make our private copy of the filter */
+
+	if (install_bpf_program(p, fp) < 0)
+		return -1;
+
+	p->md.use_bpf = 0;
+
+	return (0);
+}
+
+static int
+dag_set_datalink(pcap_t *p, int dlt)
+{
+	p->linktype = dlt;
+
+	return (0);
+}
+
+static int
+dag_setnonblock(pcap_t *p, int nonblock, char *errbuf)
+{
+	/*
+	 * Set non-blocking mode on the FD.
+	 * XXX - is that necessary?  If not, don't bother calling it,
+	 * and have a "dag_getnonblock()" function that looks at
+	 * "p->md.dag_offset_flags".
+	 */
+	if (pcap_setnonblock_fd(p, nonblock, errbuf) < 0)
+		return (-1);
+
+	if (nonblock) {
+		p->md.dag_offset_flags |= DAGF_NONBLOCK;
+	} else {
+		p->md.dag_offset_flags &= ~DAGF_NONBLOCK;
+	}
+	return (0);
+}
+		
+static int
+dag_get_datalink(pcap_t *p)
+{
+	int daglinktype;
+
+	if (p->dlt_list == NULL && (p->dlt_list = malloc(2*sizeof(*(p->dlt_list)))) == NULL) {
+		(void)snprintf(p->errbuf, sizeof(p->errbuf), "malloc: %s", pcap_strerror(errno));
+		return (-1);
+	}
+
+	/* Check the type through a dagapi call. */
+	daglinktype = dag_linktype(p->fd);
+
+	switch(daglinktype) {
+
+	case TYPE_HDLC_POS:
+		if (p->dlt_list != NULL) {
+			p->dlt_count = 2;
+			p->dlt_list[0] = DLT_CHDLC;
+			p->dlt_list[1] = DLT_PPP_SERIAL;
+		}
+		p->linktype = DLT_CHDLC;
+		break;
+
+	case TYPE_ETH:
+		/*
+		 * This is (presumably) a real Ethernet capture; give it a
+		 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
+		 * that an application can let you choose it, in case you're
+		 * capturing DOCSIS traffic that a Cisco Cable Modem
+		 * Termination System is putting out onto an Ethernet (it
+		 * doesn't put an Ethernet header onto the wire, it puts raw
+		 * DOCSIS frames out on the wire inside the low-level
+		 * Ethernet framing).
+		 */
+		if (p->dlt_list != NULL) {
+			p->dlt_count = 2;
+			p->dlt_list[0] = DLT_EN10MB;
+			p->dlt_list[1] = DLT_DOCSIS;
+		}
+		p->linktype = DLT_EN10MB;
+		break;
+
+	case TYPE_AAL5:
+	case TYPE_ATM: 
+		if (p->dlt_list != NULL) {
+			p->dlt_count = 2;
+			p->dlt_list[0] = DLT_ATM_RFC1483;
+			p->dlt_list[1] = DLT_SUNATM;
+		}
+		p->linktype = DLT_ATM_RFC1483;
+		break;
+
+
+	case TYPE_LEGACY:
+		p->linktype = DLT_NULL;
+		break;
+
+	default:
+		snprintf(p->errbuf, sizeof(p->errbuf), "unknown DAG linktype %d\n", daglinktype);
+		return (-1);
+
+	}
+
+	return p->linktype;
+}