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-rw-r--r--contrib/libpcap/pcap-dag.c710
1 files changed, 710 insertions, 0 deletions
diff --git a/contrib/libpcap/pcap-dag.c b/contrib/libpcap/pcap-dag.c
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+++ b/contrib/libpcap/pcap-dag.c
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+/*
+ * 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.
+ *
+ * Author: Richard Littin, Sean Irvine ({richard,sean}@reeltwo.com)
+ *
+ * Modifications:
+ * 2003 May - Jesper Peterson <support@endace.com>
+ * Code shuffled around to suit fad-xxx.c structure
+ * Added atexit() handler to stop DAG if application is too lazy
+ * 2003 September - Koryn Grant <koryn@endace.com>
+ * Added support for nonblocking operation.
+ * Added support for processing more than a single packet in pcap_dispatch().
+ * Fixed bug in loss counter code.
+ * Improved portability of loss counter code (e.g. use UINT_MAX instead of 0xffff).
+ * Removed unused local variables.
+ * Added required headers (ctype.h, limits.h, unistd.h, netinet/in.h).
+ * 2003 October - Koryn Grant <koryn@endace.com.>
+ * Changed semantics to match those of standard pcap on linux.
+ * - packets rejected by the filter are not counted.
+ */
+
+#ifndef lint
+static const char rcsid[] _U_ =
+ "@(#) $Header: /tcpdump/master/libpcap/pcap-dag.c,v 1.10.2.4 2003/11/21 10:20:45 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_SNAPLEN 48
+
+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 ((p->md.dag_mem_top - p->md.dag_mem_bottom < dag_record_size) && nonblocking)
+ {
+ /* 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;
+ }
+
+ if (IS_BIGENDIAN())
+ {
+ rlen = header->rlen;
+ }
+ else
+ {
+ rlen = ntohs(header->rlen);
+ }
+ p->md.dag_mem_bottom += rlen;
+
+ switch(header->type) {
+ case TYPE_ATM:
+ packet_len = ATM_SNAPLEN;
+ caplen = ATM_SNAPLEN;
+ dp += 4;
+ break;
+
+ case TYPE_ETH:
+ if (IS_BIGENDIAN())
+ {
+ packet_len = header->wlen;
+ }
+ else
+ {
+ 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:
+ if (IS_BIGENDIAN())
+ {
+ packet_len = header->wlen;
+ }
+ else
+ {
+ 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 - header->lctr)) {
+ p->md.stat.ps_drop = UINT_MAX;
+ } else {
+ p->md.stat.ps_drop += 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;
+}
+
+/*
+ * 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;
+
+ 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);
+
+ fprintf(stderr, "Configuring DAG with '%s'.\n", conf);
+ 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;
+
+ /* TODO: query the card */
+ handle->md.dag_fcs_bits = 32;
+ 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; */
+
+ if ((handle->linktype = dag_get_datalink(handle)) < 0) {
+ snprintf(ebuf, PCAP_ERRBUF_SIZE, "dag_get_linktype %s: unknown linktype\n", device);
+ 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->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) {
+ 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) {
+ snprintf(p->errbuf, sizeof(p->errbuf),
+ "malloc: %s", pcap_strerror(errno));
+ return -1;
+ }
+
+ p->md.use_bpf = 0;
+
+ return (0);
+}
+
+static int
+dag_set_datalink(pcap_t *p, int 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 linktype = -1;
+
+ /* Check the type through a dagapi call.
+ */
+ switch(dag_linktype(p->fd)) {
+ case TYPE_HDLC_POS: {
+ dag_record_t *record;
+
+ /* peek at the first available record to see if it is PPP */
+ while ((p->md.dag_mem_top - p->md.dag_mem_bottom) < (dag_record_size + 4)) {
+ p->md.dag_mem_top = dag_offset(p->fd, &(p->md.dag_mem_bottom), 0);
+ }
+ record = (dag_record_t *)(p->md.dag_mem_base + p->md.dag_mem_bottom);
+
+ if ((ntohl(record->rec.pos.hdlc) & 0xffff0000) == 0xff030000) {
+ linktype = DLT_PPP_SERIAL;
+ fprintf(stderr, "Set DAG linktype to %d (DLT_PPP_SERIAL)\n", linktype);
+ } else {
+ linktype = DLT_CHDLC;
+ fprintf(stderr, "Set DAG linktype to %d (DLT_CHDLC)\n", linktype);
+ }
+ break;
+ }
+ case TYPE_ETH:
+ linktype = DLT_EN10MB;
+ fprintf(stderr, "Set DAG linktype to %d (DLT_EN10MB)\n", linktype);
+ break;
+ case TYPE_ATM:
+ linktype = DLT_ATM_RFC1483;
+ fprintf(stderr, "Set DAG linktype to %d (DLT_ATM_RFC1483)\n", linktype);
+ break;
+ case TYPE_LEGACY:
+ linktype = DLT_NULL;
+ fprintf(stderr, "Set DAG linktype to %d (DLT_NULL)\n", linktype);
+ break;
+ default:
+ fprintf(stderr, "Unknown DAG linktype %d\n", dag_linktype(p->fd));
+ break;
+ }
+
+ return linktype;
+}
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