diff options
Diffstat (limited to 'src/libnet_build_dhcp.c')
| -rw-r--r-- | src/libnet_build_dhcp.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/src/libnet_build_dhcp.c b/src/libnet_build_dhcp.c new file mode 100644 index 0000000..0fc49fa --- /dev/null +++ b/src/libnet_build_dhcp.c @@ -0,0 +1,135 @@ +/* + * $Id: libnet_build_dhcp.c,v 1.10 2004/03/01 20:26:12 mike Exp $ + * + * libnet + * libnet_build_dhcp.c - DHCP/BOOTP 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. + * + */ + +#include "common.h" + +libnet_ptag_t +libnet_build_dhcpv4(uint8_t opcode, uint8_t htype, uint8_t hlen, +uint8_t hopcount, uint32_t xid, uint16_t secs, uint16_t flags, +uint32_t cip, uint32_t yip, uint32_t sip, uint32_t gip, const uint8_t *chaddr, +const char *sname, const char *file, const uint8_t *payload, uint32_t payload_s, +libnet_t *l, libnet_ptag_t ptag) +{ + uint32_t n, h; + libnet_pblock_t *p; + struct libnet_dhcpv4_hdr dhcp_hdr; + + if (l == NULL) + { + return (-1); + } + + n = LIBNET_DHCPV4_H + payload_s; + h = 0; /* no checksum */ + + /* + * Find the existing protocol block if a ptag is specified, or create + * a new one. + */ + p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_DHCPV4_H); + if (p == NULL) + { + return (-1); + } + + memset(&dhcp_hdr, 0, sizeof(dhcp_hdr)); + dhcp_hdr.dhcp_opcode = opcode; + dhcp_hdr.dhcp_htype = htype; + dhcp_hdr.dhcp_hlen = hlen; + dhcp_hdr.dhcp_hopcount = hopcount; + dhcp_hdr.dhcp_xid = htonl(xid); + dhcp_hdr.dhcp_secs = htons(secs); + dhcp_hdr.dhcp_flags = htons(flags); + dhcp_hdr.dhcp_cip = htonl(cip); + dhcp_hdr.dhcp_yip = htonl(yip); + dhcp_hdr.dhcp_sip = htonl(sip); + dhcp_hdr.dhcp_gip = htonl(gip); + + if (chaddr) + { + size_t n = sizeof (dhcp_hdr.dhcp_chaddr); + if (hlen < n) + n = hlen; + memcpy(dhcp_hdr.dhcp_chaddr, chaddr, n); + } + if (sname) + { + strncpy(dhcp_hdr.dhcp_sname, sname, sizeof (dhcp_hdr.dhcp_sname) - 1); + } + if (file) + { + strncpy(dhcp_hdr.dhcp_file, file, sizeof (dhcp_hdr.dhcp_file) - 1); + } + dhcp_hdr.dhcp_magic = htonl(DHCP_MAGIC); + + n = libnet_pblock_append(l, p, (uint8_t *)&dhcp_hdr, LIBNET_DHCPV4_H); + if (n == -1) + { + goto bad; + } + + if (payload_s && !payload) + { + snprintf(l->err_buf, LIBNET_ERRBUF_SIZE, + "%s(): payload inconsistency", __func__); + goto bad; + } + + if (payload_s) + { + n = libnet_pblock_append(l, p, payload, payload_s); + if (n == -1) + { + goto bad; + } + } + + return (ptag ? ptag : libnet_pblock_update(l, p, h, + LIBNET_PBLOCK_DHCPV4_H)); +bad: + libnet_pblock_delete(l, p); + return (-1); +} + +libnet_ptag_t +libnet_build_bootpv4(uint8_t opcode, uint8_t htype, uint8_t hlen, +uint8_t hopcount, uint32_t xid, uint16_t secs, uint16_t flags, +uint32_t cip, uint32_t yip, uint32_t sip, uint32_t gip, const uint8_t *chaddr, +const char *sname, const char *file, const uint8_t *payload, uint32_t payload_s, +libnet_t *l, libnet_ptag_t ptag) +{ + return (libnet_build_dhcpv4(opcode, htype, hlen, hopcount, xid, secs, + flags, cip, yip, sip, gip, chaddr, sname, file, payload, payload_s, + l, ptag)); +} + +/* EOF */ |