* This module now handles the STREAMS based NIT.
*/
-#ifndef lint
-static const char rcsid[] =
- "@(#) $Header: /tcpdump/master/libpcap/pcap-snit.c,v 1.57 2002-07-11 09:06:43 guy Exp $ (LBL)";
-#endif
-
#ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
#endif
#include <sys/types.h>
#include <netinet/tcp.h>
#include <netinet/tcpip.h>
-#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
/* Forwards */
static int nit_setflags(int, int, int, char *);
-int
-pcap_stats(pcap_t *p, struct pcap_stat *ps)
+/*
+ * Private data for capturing on STREAMS NIT devices.
+ */
+struct pcap_snit {
+ struct pcap_stat stat;
+};
+
+static int
+pcap_stats_snit(pcap_t *p, struct pcap_stat *ps)
{
+ struct pcap_snit *psn = p->priv;
/*
* "ps_recv" counts packets handed to the filter, not packets
* kernel by libpcap or packets not yet read from libpcap by the
* application.
*/
- *ps = p->md.stat;
+ *ps = psn->stat;
return (0);
}
-int
-pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
+static int
+pcap_read_snit(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
+ struct pcap_snit *psn = p->priv;
register int cc, n;
- register struct bpf_insn *fcode = p->fcode.bf_insns;
register u_char *bp, *cp, *ep;
register struct nit_bufhdr *hdrp;
register struct nit_iftime *ntp;
if (cc < 0) {
if (errno == EWOULDBLOCK)
return (0);
- snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s",
- pcap_strerror(errno));
+ pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
+ errno, "pcap_read");
return (-1);
}
- bp = p->buffer;
+ bp = (u_char *)p->buffer;
} else
bp = p->bp;
/*
* loop through each snapshot in the chunk
+ *
+ * This assumes that a single buffer of packets will have
+ * <= INT_MAX packets, so the packet count doesn't overflow.
*/
n = 0;
ep = bp + cc;
while (bp < ep) {
- ++p->md.stat.ps_recv;
+ /*
+ * Has "pcap_breakloop()" been called?
+ * If so, return immediately - if we haven't read any
+ * packets, clear the flag and return -2 to indicate
+ * that we were told to break out of the loop, otherwise
+ * leave the flag set, so that the *next* call will break
+ * out of the loop without having read any packets, and
+ * return the number of packets we've processed so far.
+ */
+ if (p->break_loop) {
+ if (n == 0) {
+ p->break_loop = 0;
+ return (-2);
+ } else {
+ p->bp = bp;
+ p->cc = ep - bp;
+ return (n);
+ }
+ }
+
+ ++psn->stat.ps_recv;
cp = bp;
/* get past NIT buffer */
cp += sizeof(*ntp);
ndp = (struct nit_ifdrops *)cp;
- p->md.stat.ps_drop = ndp->nh_drops;
+ psn->stat.ps_drop = ndp->nh_drops;
cp += sizeof *ndp;
/* get past packet len */
if (caplen > p->snapshot)
caplen = p->snapshot;
- if (bpf_filter(fcode, cp, nlp->nh_pktlen, caplen)) {
+ if (pcap_filter(p->fcode.bf_insns, cp, nlp->nh_pktlen, caplen)) {
struct pcap_pkthdr h;
h.ts = ntp->nh_timestamp;
h.len = nlp->nh_pktlen;
h.caplen = caplen;
(*callback)(user, &h, cp);
- if (++n >= cnt && cnt >= 0) {
+ if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt)) {
p->cc = ep - bp;
p->bp = bp;
return (n);
}
static int
-nit_setflags(int fd, int promisc, int to_ms, char *ebuf)
+pcap_inject_snit(pcap_t *p, const void *buf, int size)
+{
+ struct strbuf ctl, data;
+
+ /*
+ * XXX - can we just do
+ *
+ ret = write(pd->f, buf, size);
+ */
+ ctl.len = sizeof(*sa); /* XXX - what was this? */
+ ctl.buf = (char *)sa;
+ data.buf = buf;
+ data.len = size;
+ ret = putmsg(p->fd, &ctl, &data);
+ if (ret == -1) {
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "send");
+ return (-1);
+ }
+ return (ret);
+}
+
+static int
+nit_setflags(pcap_t *p)
{
bpf_u_int32 flags;
struct strioctl si;
+ u_int zero = 0;
struct timeval timeout;
+ if (p->opt.immediate) {
+ /*
+ * Set the chunk size to zero, so that chunks get sent
+ * up immediately.
+ */
+ si.ic_cmd = NIOCSCHUNK;
+ si.ic_len = sizeof(zero);
+ si.ic_dp = (char *)&zero;
+ if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "NIOCSCHUNK");
+ return (-1);
+ }
+ }
si.ic_timout = INFTIM;
- if (to_ms != 0) {
- timeout.tv_sec = to_ms / 1000;
- timeout.tv_usec = (to_ms * 1000) % 1000000;
+ if (p->opt.timeout != 0) {
+ timeout.tv_sec = p->opt.timeout / 1000;
+ timeout.tv_usec = (p->opt.timeout * 1000) % 1000000;
si.ic_cmd = NIOCSTIME;
si.ic_len = sizeof(timeout);
si.ic_dp = (char *)&timeout;
- if (ioctl(fd, I_STR, (char *)&si) < 0) {
- snprintf(ebuf, PCAP_ERRBUF_SIZE, "NIOCSTIME: %s",
- pcap_strerror(errno));
+ if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "NIOCSTIME");
return (-1);
}
}
flags = NI_TIMESTAMP | NI_LEN | NI_DROPS;
- if (promisc)
+ if (p->opt.promisc)
flags |= NI_PROMISC;
si.ic_cmd = NIOCSFLAGS;
si.ic_len = sizeof(flags);
si.ic_dp = (char *)&flags;
- if (ioctl(fd, I_STR, (char *)&si) < 0) {
- snprintf(ebuf, PCAP_ERRBUF_SIZE, "NIOCSFLAGS: %s",
- pcap_strerror(errno));
+ if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "NIOCSFLAGS");
return (-1);
}
return (0);
}
-pcap_t *
-pcap_open_live(char *device, int snaplen, int promisc, int to_ms, char *ebuf)
+static int
+pcap_activate_snit(pcap_t *p)
{
struct strioctl si; /* struct for ioctl() */
struct ifreq ifr; /* interface request struct */
int chunksize = CHUNKSIZE;
int fd;
- static char dev[] = "/dev/nit";
- register pcap_t *p;
+ static const char dev[] = "/dev/nit";
+ int err;
- p = (pcap_t *)malloc(sizeof(*p));
- if (p == NULL) {
- strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
- return (NULL);
+ if (p->opt.rfmon) {
+ /*
+ * No monitor mode on SunOS 4.x (no Wi-Fi devices on
+ * hardware supported by SunOS 4.x).
+ */
+ return (PCAP_ERROR_RFMON_NOTSUP);
}
- if (snaplen < 96)
+ /*
+ * Turn a negative snapshot value (invalid), a snapshot value of
+ * 0 (unspecified), or a value bigger than the normal maximum
+ * value, into the maximum allowed value.
+ *
+ * If some application really *needs* a bigger snapshot
+ * length, we should just increase MAXIMUM_SNAPLEN.
+ */
+ if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)
+ p->snapshot = MAXIMUM_SNAPLEN;
+
+ if (p->snapshot < 96)
/*
* NIT requires a snapshot length of at least 96.
*/
- snaplen = 96;
+ p->snapshot = 96;
- memset(p, 0, sizeof(*p));
- p->fd = fd = open(dev, O_RDONLY);
+ /*
+ * Initially try a read/write open (to allow the inject
+ * method to work). If that fails due to permission
+ * issues, fall back to read-only. This allows a
+ * non-root user to be granted specific access to pcap
+ * capabilities via file permissions.
+ *
+ * XXX - we should have an API that has a flag that
+ * controls whether to open read-only or read-write,
+ * so that denial of permission to send (or inability
+ * to send, if sending packets isn't supported on
+ * the device in question) can be indicated at open
+ * time.
+ */
+ p->fd = fd = open(dev, O_RDWR);
+ if (fd < 0 && errno == EACCES)
+ p->fd = fd = open(dev, O_RDONLY);
if (fd < 0) {
- snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s: %s", dev,
- pcap_strerror(errno));
+ if (errno == EACCES) {
+ err = PCAP_ERROR_PERM_DENIED;
+ snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
+ "Attempt to open %s failed with EACCES - root privileges may be required",
+ dev);
+ } else {
+ err = PCAP_ERROR;
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "%s", dev);
+ }
goto bad;
}
/* arrange to get discrete messages from the STREAM and use NIT_BUF */
if (ioctl(fd, I_SRDOPT, (char *)RMSGD) < 0) {
- snprintf(ebuf, PCAP_ERRBUF_SIZE, "I_SRDOPT: %s",
- pcap_strerror(errno));
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "I_SRDOPT");
+ err = PCAP_ERROR;
goto bad;
}
if (ioctl(fd, I_PUSH, "nbuf") < 0) {
- snprintf(ebuf, PCAP_ERRBUF_SIZE, "push nbuf: %s",
- pcap_strerror(errno));
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "push nbuf");
+ err = PCAP_ERROR;
goto bad;
}
/* set the chunksize */
si.ic_len = sizeof(chunksize);
si.ic_dp = (char *)&chunksize;
if (ioctl(fd, I_STR, (char *)&si) < 0) {
- snprintf(ebuf, PCAP_ERRBUF_SIZE, "NIOCSCHUNK: %s",
- pcap_strerror(errno));
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "NIOCSCHUNK");
+ err = PCAP_ERROR;
goto bad;
}
/* request the interface */
- strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
- ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = ' ';
+ strncpy(ifr.ifr_name, p->opt.device, sizeof(ifr.ifr_name));
+ ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = '\0';
si.ic_cmd = NIOCBIND;
si.ic_len = sizeof(ifr);
si.ic_dp = (char *)𝔦
if (ioctl(fd, I_STR, (char *)&si) < 0) {
- snprintf(ebuf, PCAP_ERRBUF_SIZE, "NIOCBIND: %s: %s",
- ifr.ifr_name, pcap_strerror(errno));
+ /*
+ * XXX - is there an error that means "no such device"?
+ * Is there one that means "that device doesn't support
+ * STREAMS NIT"?
+ */
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "NIOCBIND: %s", ifr.ifr_name);
+ err = PCAP_ERROR;
goto bad;
}
/* set the snapshot length */
si.ic_cmd = NIOCSSNAP;
- si.ic_len = sizeof(snaplen);
- si.ic_dp = (char *)&snaplen;
+ si.ic_len = sizeof(p->snapshot);
+ si.ic_dp = (char *)&p->snapshot;
if (ioctl(fd, I_STR, (char *)&si) < 0) {
- snprintf(ebuf, PCAP_ERRBUF_SIZE, "NIOCSSNAP: %s",
- pcap_strerror(errno));
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "NIOCSSNAP");
+ err = PCAP_ERROR;
goto bad;
}
- p->snapshot = snaplen;
- if (nit_setflags(p->fd, promisc, to_ms, ebuf) < 0)
+ if (nit_setflags(p) < 0) {
+ err = PCAP_ERROR;
goto bad;
+ }
(void)ioctl(fd, I_FLUSH, (char *)FLUSHR);
/*
p->linktype = DLT_EN10MB;
p->bufsize = BUFSPACE;
- p->buffer = (u_char *)malloc(p->bufsize);
+ p->buffer = malloc(p->bufsize);
if (p->buffer == NULL) {
- strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
+ pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
+ errno, "malloc");
+ err = PCAP_ERROR;
goto bad;
}
- return (p);
+
+ /*
+ * "p->fd" is an FD for a STREAMS device, so "select()" and
+ * "poll()" should work on it.
+ */
+ p->selectable_fd = p->fd;
+
+ /*
+ * 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).
+ */
+ p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
+ /*
+ * If that fails, just leave the list empty.
+ */
+ if (p->dlt_list != NULL) {
+ p->dlt_list[0] = DLT_EN10MB;
+ p->dlt_list[1] = DLT_DOCSIS;
+ p->dlt_count = 2;
+ }
+
+ p->read_op = pcap_read_snit;
+ p->inject_op = pcap_inject_snit;
+ p->setfilter_op = install_bpf_program; /* no kernel filtering */
+ p->setdirection_op = NULL; /* Not implemented. */
+ p->set_datalink_op = NULL; /* can't change data link type */
+ p->getnonblock_op = pcap_getnonblock_fd;
+ p->setnonblock_op = pcap_setnonblock_fd;
+ p->stats_op = pcap_stats_snit;
+
+ return (0);
bad:
- if (fd >= 0)
- close(fd);
- free(p);
- return (NULL);
+ pcap_cleanup_live_common(p);
+ return (err);
}
-int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_t *
+pcap_create_interface(const char *device _U_, char *ebuf)
{
+ pcap_t *p;
+
+ p = PCAP_CREATE_COMMON(ebuf, struct pcap_snit);
+ if (p == NULL)
+ return (NULL);
+
+ p->activate_op = pcap_activate_snit;
+ return (p);
+}
+
+/*
+ * XXX - there's probably a NIOCBIND error that means "that device
+ * doesn't support NIT"; if so, we should try an NIOCBIND and use that.
+ */
+static int
+can_be_bound(const char *name _U_)
+{
+ return (1);
+}
+
+static int
+get_if_flags(const char *name _U_, bpf_u_int32 *flags _U_, char *errbuf _U_)
+{
+ /*
+ * Nothing we can do.
+ * XXX - is there a way to find out whether an adapter has
+ * something plugged into it?
+ */
return (0);
}
int
-pcap_setfilter(pcap_t *p, struct bpf_program *fp)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
{
+ return (pcap_findalldevs_interfaces(devlistp, errbuf, can_be_bound,
+ get_if_flags));
+}
- if (install_bpf_program(p, fp) < 0)
- return (-1);
- return (0);
+/*
+ * Libpcap version string.
+ */
+const char *
+pcap_lib_version(void)
+{
+ return (PCAP_VERSION_STRING);
}
projects / libpcap / blobdiff