1 files changed, 137 insertions, 0 deletions
diff --git a/arch/um/drivers/pcap_user.c b/arch/um/drivers/pcap_user.c
new file mode 100644
index 000000000..52ddda3e3
--- /dev/null
+++ b/arch/um/drivers/pcap_user.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ */
+
+#include <errno.h>
+#include <pcap.h>
+#include <string.h>
+#include <asm/types.h>
+#include <net_user.h>
+#include "pcap_user.h"
+#include <um_malloc.h>
+
+#define PCAP_FD(p) (*(int *)(p))
+
+static int pcap_user_init(void *data, void *dev)
+{
+	struct pcap_data *pri = data;
+	pcap_t *p;
+	char errors[PCAP_ERRBUF_SIZE];
+
+	p = pcap_open_live(pri->host_if, ETH_MAX_PACKET + ETH_HEADER_OTHER,
+			   pri->promisc, 0, errors);
+	if (p == NULL) {
+		printk(UM_KERN_ERR "pcap_user_init : pcap_open_live failed - "
+		       "'%s'\n", errors);
+		return -EINVAL;
+	}
+
+	pri->dev = dev;
+	pri->pcap = p;
+	return 0;
+}
+
+static int pcap_user_open(void *data)
+{
+	struct pcap_data *pri = data;
+	__u32 netmask;
+	int err;
+
+	if (pri->pcap == NULL)
+		return -ENODEV;
+
+	if (pri->filter != NULL) {
+		err = dev_netmask(pri->dev, &netmask);
+		if (err < 0) {
+			printk(UM_KERN_ERR "pcap_user_open : dev_netmask failed\n");
+			return -EIO;
+		}
+
+		pri->compiled = uml_kmalloc(sizeof(struct bpf_program),
+					UM_GFP_KERNEL);
+		if (pri->compiled == NULL) {
+			printk(UM_KERN_ERR "pcap_user_open : kmalloc failed\n");
+			return -ENOMEM;
+		}
+
+		err = pcap_compile(pri->pcap,
+				   (struct bpf_program *) pri->compiled,
+				   pri->filter, pri->optimize, netmask);
+		if (err < 0) {
+			printk(UM_KERN_ERR "pcap_user_open : pcap_compile failed - "
+			       "'%s'\n", pcap_geterr(pri->pcap));
+			goto out;
+		}
+
+		err = pcap_setfilter(pri->pcap, pri->compiled);
+		if (err < 0) {
+			printk(UM_KERN_ERR "pcap_user_open : pcap_setfilter "
+			       "failed - '%s'\n", pcap_geterr(pri->pcap));
+			goto out;
+		}
+	}
+
+	return PCAP_FD(pri->pcap);
+
+ out:
+	kfree(pri->compiled);
+	return -EIO;
+}
+
+static void pcap_remove(void *data)
+{
+	struct pcap_data *pri = data;
+
+	if (pri->compiled != NULL)
+		pcap_freecode(pri->compiled);
+
+	if (pri->pcap != NULL)
+		pcap_close(pri->pcap);
+}
+
+struct pcap_handler_data {
+	char *buffer;
+	int len;
+};
+
+static void handler(u_char *data, const struct pcap_pkthdr *header,
+		    const u_char *packet)
+{
+	int len;
+
+	struct pcap_handler_data *hdata = (struct pcap_handler_data *) data;
+
+	len = hdata->len < header->caplen ? hdata->len : header->caplen;
+	memcpy(hdata->buffer, packet, len);
+	hdata->len = len;
+}
+
+int pcap_user_read(int fd, void *buffer, int len, struct pcap_data *pri)
+{
+	struct pcap_handler_data hdata = ((struct pcap_handler_data)
+		                          { .buffer  	= buffer,
+					    .len 	= len });
+	int n;
+
+	n = pcap_dispatch(pri->pcap, 1, handler, (u_char *) &hdata);
+	if (n < 0) {
+		printk(UM_KERN_ERR "pcap_dispatch failed - %s\n",
+		       pcap_geterr(pri->pcap));
+		return -EIO;
+	}
+	else if (n == 0)
+		return 0;
+	return hdata.len;
+}
+
+const struct net_user_info pcap_user_info = {
+	.init		= pcap_user_init,
+	.open		= pcap_user_open,
+	.close	 	= NULL,
+	.remove	 	= pcap_remove,
+	.add_address	= NULL,
+	.delete_address = NULL,
+	.mtu		= ETH_MAX_PACKET,
+	.max_packet	= ETH_MAX_PACKET + ETH_HEADER_OTHER,
+};