all: import netsniff-ng 0.5.8-rc0 source

We decided to get rid of the old Git history and start a new one for
several reasons:

 *) Allow / enforce only high-quality commits (which was not the case
    for many commits in the history), have a policy that is more close
    to the one from the Linux kernel. With high quality commits, we
    mean code that is logically split into commits and commit messages
    that are signed-off and have a proper subject and message body.
    We do not allow automatic Github merges anymore, since they are
    total bullshit. However, we will either cherry-pick your patches
    or pull them manually.

 *) The old archive was about ~27MB for no particular good reason.
    This basically derived from the bad decision that also some PDF
    files where stored there. From this moment onwards, no binary
    objects are allowed to be stored in this repository anymore.

The old archive is not wiped away from the Internet. You will still
be able to find it, e.g. on git.cryptoism.org etc.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

1 files changed, 193 insertions, 0 deletions

diff --git a/pcap_sg.c b/pcap_sg.c
new file mode 100644
index 0000000..ad78ce7
--- /dev/null
+++ b/pcap_sg.c
@@ -0,0 +1,193 @@
+/*
+ * netsniff-ng - the packet sniffing beast
+ * Copyright 2011 - 2013 Daniel Borkmann.
+ * Subject to the GPL, version 2.
+ */
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/uio.h>
+#include <unistd.h>
+
+#include "pcap_io.h"
+#include "xmalloc.h"
+#include "xio.h"
+#include "xutils.h"
+#include "built_in.h"
+
+static struct iovec iov[1024] __cacheline_aligned;
+static off_t iov_off_rd = 0, iov_slot = 0;
+
+static ssize_t pcap_sg_write(int fd, pcap_pkthdr_t *phdr, enum pcap_type type,
+			     const uint8_t *packet, size_t len)
+{
+	ssize_t ret, hdrsize = pcap_get_hdr_length(phdr, type);
+
+	if (unlikely(iov_slot == array_size(iov))) {
+		ret = writev(fd, iov, array_size(iov));
+		if (ret < 0)
+			panic("Writev I/O error: %s!\n", strerror(errno));
+
+		iov_slot = 0;
+	}
+
+	fmemcpy(iov[iov_slot].iov_base, &phdr->raw, hdrsize);
+	iov[iov_slot].iov_len = hdrsize;
+
+	fmemcpy(iov[iov_slot].iov_base + iov[iov_slot].iov_len, packet, len);
+	ret = (iov[iov_slot].iov_len += len);
+
+	iov_slot++;
+	return ret;
+}
+
+static ssize_t __pcap_sg_inter_iov_hdr_read(int fd, pcap_pkthdr_t *phdr, enum pcap_type type,
+					    uint8_t *packet, size_t len, size_t hdrsize)
+{
+	int ret;
+	size_t offset = 0;
+	ssize_t remainder;
+
+	offset = iov[iov_slot].iov_len - iov_off_rd;
+	remainder = hdrsize - offset;
+	if (remainder < 0)
+		remainder = 0;
+
+	bug_on(offset + remainder != hdrsize);
+
+	fmemcpy(&phdr->raw, iov[iov_slot].iov_base + iov_off_rd, offset);
+	iov_off_rd = 0;
+	iov_slot++;
+
+	if (iov_slot == array_size(iov)) {
+		iov_slot = 0;
+		ret = readv(fd, iov, array_size(iov));
+		if (unlikely(ret <= 0))
+			return -EIO;
+	}
+
+	fmemcpy(&phdr->raw + offset, iov[iov_slot].iov_base + iov_off_rd, remainder);
+	iov_off_rd += remainder;
+
+	return hdrsize;
+}
+
+static ssize_t __pcap_sg_inter_iov_data_read(int fd, uint8_t *packet, size_t len, size_t hdrlen)
+{
+	int ret;
+	size_t offset = 0;
+	ssize_t remainder;
+
+	offset = iov[iov_slot].iov_len - iov_off_rd;
+	remainder = hdrlen - offset;
+	if (remainder < 0)
+		remainder = 0;
+
+	bug_on(offset + remainder != hdrlen);
+
+	fmemcpy(packet, iov[iov_slot].iov_base + iov_off_rd, offset);
+	iov_off_rd = 0;
+	iov_slot++;
+
+	if (iov_slot == array_size(iov)) {
+		iov_slot = 0;
+		ret = readv(fd, iov, array_size(iov));
+		if (unlikely(ret <= 0))
+			return -EIO;
+	}
+
+	fmemcpy(packet + offset, iov[iov_slot].iov_base + iov_off_rd, remainder);
+	iov_off_rd += remainder;
+
+	return hdrlen;
+}
+
+static ssize_t pcap_sg_read(int fd, pcap_pkthdr_t *phdr, enum pcap_type type,
+			    uint8_t *packet, size_t len)
+{
+	ssize_t ret = 0;
+	size_t hdrsize = pcap_get_hdr_length(phdr, type), hdrlen;
+
+	if (likely(iov[iov_slot].iov_len - iov_off_rd >= hdrsize)) {
+		fmemcpy(&phdr->raw, iov[iov_slot].iov_base + iov_off_rd, hdrsize);
+		iov_off_rd += hdrsize;
+	} else {
+		ret = __pcap_sg_inter_iov_hdr_read(fd, phdr, type, packet,
+						   len, hdrsize);
+		if (unlikely(ret < 0))
+			return ret;
+	}
+
+	hdrlen = pcap_get_length(phdr, type);
+	if (unlikely(hdrlen == 0 || hdrlen > len))
+		return -EINVAL;
+
+	if (likely(iov[iov_slot].iov_len - iov_off_rd >= hdrlen)) {
+		fmemcpy(packet, iov[iov_slot].iov_base + iov_off_rd, hdrlen);
+		iov_off_rd += hdrlen;
+	} else {
+		ret = __pcap_sg_inter_iov_data_read(fd, packet, len, hdrlen);
+		if (unlikely(ret < 0))
+			return ret;
+	}
+
+	return hdrsize + hdrlen;
+}
+
+static void pcap_sg_fsync(int fd)
+{
+	ssize_t ret = writev(fd, iov, iov_slot);
+	if (ret < 0)
+		panic("Writev I/O error: %s!\n", strerror(errno));
+
+	iov_slot = 0;
+	fdatasync(fd);
+}
+
+static int pcap_sg_prepare_access(int fd, enum pcap_mode mode, bool jumbo)
+{
+	int i, ret;
+	size_t len = 0;
+
+	iov_slot = 0;
+	len = jumbo ? (PAGE_SIZE * 16) /* 64k max */ :
+		      (PAGE_SIZE *  3) /* 12k max */;
+
+	for (i = 0; i < array_size(iov); ++i) {
+		iov[i].iov_base = xzmalloc_aligned(len, 64);
+		iov[i].iov_len = len;
+	}
+
+	set_ioprio_rt();
+
+	if (mode == PCAP_MODE_RD) {
+		ret = readv(fd, iov, array_size(iov));
+		if (ret <= 0)
+			return -EIO;
+
+		iov_off_rd = 0;
+		iov_slot = 0;
+	}
+
+	return 0;
+}
+
+static void pcap_sg_prepare_close(int fd, enum pcap_mode mode)
+{
+	int i;
+
+	for (i = 0; i < array_size(iov); ++i)
+		xfree(iov[i].iov_base);
+}
+
+const struct pcap_file_ops pcap_sg_ops = {
+	.pull_fhdr_pcap = pcap_generic_pull_fhdr,
+	.push_fhdr_pcap = pcap_generic_push_fhdr,
+	.prepare_access_pcap =  pcap_sg_prepare_access,
+	.prepare_close_pcap = pcap_sg_prepare_close,
+	.read_pcap = pcap_sg_read,
+	.write_pcap = pcap_sg_write,
+	.fsync_pcap = pcap_sg_fsync,
+};