Add support for processing ICMP packets using pkt_buff, similar to existing library support for TCP and UDP. Signed-off-by: Etan Kissling <etan_kissling@xxxxxxxxx> --- include/libnetfilter_queue/Makefile.am | 1 + .../libnetfilter_queue_icmp.h | 8 ++++ src/Makefile.am | 1 + src/extra/icmp.c | 48 +++++++++++++++++++ 4 files changed, 58 insertions(+) create mode 100644 include/libnetfilter_queue/libnetfilter_queue_icmp.h create mode 100644 src/extra/icmp.c diff --git a/include/libnetfilter_queue/Makefile.am b/include/libnetfilter_queue/Makefile.am index 902fbf9..e436bab 100644 --- a/include/libnetfilter_queue/Makefile.am +++ b/include/libnetfilter_queue/Makefile.am @@ -1,5 +1,6 @@ pkginclude_HEADERS = libnetfilter_queue.h \ linux_nfnetlink_queue.h \ + libnetfilter_queue_icmp.h \ libnetfilter_queue_ipv4.h \ libnetfilter_queue_ipv6.h \ libnetfilter_queue_tcp.h \ diff --git a/include/libnetfilter_queue/libnetfilter_queue_icmp.h b/include/libnetfilter_queue/libnetfilter_queue_icmp.h new file mode 100644 index 0000000..9a8bd52 --- /dev/null +++ b/include/libnetfilter_queue/libnetfilter_queue_icmp.h @@ -0,0 +1,8 @@ +#ifndef _LIBNFQUEUE_ICMP_H_ +#define _LIBNFQUEUE_ICMP_H_ + +struct pkt_buff; + +struct icmphdr *nfq_icmp_get_hdr(struct pkt_buff *pktb); + +#endif diff --git a/src/Makefile.am b/src/Makefile.am index 8cede12..079853e 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -31,6 +31,7 @@ libnetfilter_queue_la_LDFLAGS = -Wc,-nostartfiles \ libnetfilter_queue_la_SOURCES = libnetfilter_queue.c \ nlmsg.c \ extra/checksum.c \ + extra/icmp.c \ extra/ipv6.c \ extra/tcp.c \ extra/ipv4.c \ diff --git a/src/extra/icmp.c b/src/extra/icmp.c new file mode 100644 index 0000000..a97979b --- /dev/null +++ b/src/extra/icmp.c @@ -0,0 +1,48 @@ +/* + * (C) 2012 by Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This code has been sponsored by Vyatta Inc. <http://www.vyatta.com> + */ + +#include <stdio.h> +#define _GNU_SOURCE +#include <netinet/ip_icmp.h> + +#include <libnetfilter_queue/libnetfilter_queue_icmp.h> + +#include "internal.h" + +/** + * \defgroup icmp ICMP helper functions + * @{ + */ + +/** + * nfq_icmp_get_hdr - get the ICMP header. + * \param pktb: pointer to user-space network packet buffer + * \returns validated pointer to the ICMP header or NULL if the ICMP header was + * not set or if a minimal length check fails. + * \note You have to call nfq_ip_set_transport_header() or + * nfq_ip6_set_transport_header() first to set the ICMP header. + */ +EXPORT_SYMBOL +struct icmphdr *nfq_icmp_get_hdr(struct pkt_buff *pktb) +{ + if (pktb->transport_header == NULL) + return NULL; + + /* No room for the ICMP header. */ + if (pktb_tail(pktb) - pktb->transport_header < sizeof(struct icmphdr)) + return NULL; + + return (struct icmphdr *)pktb->transport_header; +} + +/** + * @} + */ -- 2.21.1 (Apple Git-122.3)
