diff options
Diffstat (limited to 'libnet/src/libnet_build_igmp.c')
| -rw-r--r-- | libnet/src/libnet_build_igmp.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/libnet/src/libnet_build_igmp.c b/libnet/src/libnet_build_igmp.c new file mode 100644 index 0000000..beddf4e --- /dev/null +++ b/libnet/src/libnet_build_igmp.c @@ -0,0 +1,112 @@ +/* + * $Id: libnet_build_igmp.c,v 1.11 2004/01/21 19:01:29 mike Exp $ + * + * libnet + * libnet_build_igmp.c - IGMP packet assembler + * + * Copyright (c) 1998 - 2004 Mike D. Schiffman <mike@infonexus.com> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + */ + +#if (HAVE_CONFIG_H) +#include "../include/config.h" +#endif +#if (!(_WIN32) || (__CYGWIN__)) +#include "../include/libnet.h" +#else +#include "../include/win32/libnet.h" +#endif + +libnet_ptag_t +libnet_build_igmp(u_int8_t type, u_int8_t code, u_int16_t sum, u_int32_t ip, +u_int8_t *payload, u_int32_t payload_s, libnet_t *l, libnet_ptag_t ptag) +{ + u_int32_t n, h; + libnet_pblock_t *p; + struct libnet_igmp_hdr igmp_hdr; + + if (l == NULL) + { + return (-1); + } + + n = LIBNET_IGMP_H + payload_s; + h = LIBNET_IGMP_H; + + /* + * Find the existing protocol block if a ptag is specified, or create + * a new one. + */ + p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_IGMP_H); + if (p == NULL) + { + return (-1); + } + + memset(&igmp_hdr, 0, sizeof(igmp_hdr)); + igmp_hdr.igmp_type = type; /* packet type */ + igmp_hdr.igmp_code = code; /* packet code */ + igmp_hdr.igmp_sum = (sum ? htons(sum) : 0); /* packet checksum */ + igmp_hdr.igmp_group.s_addr = htonl(ip); + + n = libnet_pblock_append(l, p, (u_int8_t *)&igmp_hdr, LIBNET_IGMP_H); + if (n == -1) + { + goto bad; + } + + if ((payload && !payload_s) || (!payload && payload_s)) + { + snprintf(l->err_buf, LIBNET_ERRBUF_SIZE, + "%s(): payload inconsistency\n", __func__); + goto bad; + } + + if (payload && payload_s) + { + n = libnet_pblock_append(l, p, payload, payload_s); + if (n == -1) + { + goto bad; + } + } + if (sum == 0) + { + /* + * If checksum is zero, by default libnet will compute a checksum + * for the user. The programmer can override this by calling + * libnet_toggle_checksum(l, ptag, 1); + */ + libnet_pblock_setflags(p, LIBNET_PBLOCK_DO_CHECKSUM); + } + + + return (ptag ? ptag : libnet_pblock_update(l, p, h, LIBNET_PBLOCK_IGMP_H)); +bad: + libnet_pblock_delete(l, p); + return (-1); +} + +/* EOF */ |