--- libaitio/src/bpf.c 2013/06/25 08:45:50 1.1.2.7 +++ libaitio/src/bpf.c 2016/08/10 13:59:44 1.7.2.1 @@ -1,27 +1,51 @@ -#include "global.h" +/************************************************************************* +* (C) 2013 AITNET ltd - Sofia/Bulgaria - +* by Michael Pounov +* +* $Author: misho $ +* $Id: bpf.c,v 1.7.2.1 2016/08/10 13:59:44 misho Exp $ +* +************************************************************************** +The ELWIX and AITNET software is distributed under the following +terms: +All of the documentation and software included in the ELWIX and AITNET +Releases is copyrighted by ELWIX - Sofia/Bulgaria -/* - * io_get1stiface() - Get first interface of host - * - * @szIface = interface string buffer - * @iflen = size of interface buffer - * return: -1 error or 0 ok - */ -int -io_get1stiface(char *szIface, int iflen) -{ - struct ifaddrs *ifa; +Copyright 2004 - 2016 + by Michael Pounov . All rights reserved. - if (!szIface || !iflen) - return -1; +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. +3. All advertising materials mentioning features or use of this software + must display the following acknowledgement: +This product includes software developed by Michael Pounov +ELWIX - Embedded LightWeight unIX and its contributors. +4. Neither the name of AITNET nor the names of its contributors + may be used to endorse or promote products derived from this software + without specific prior written permission. - getifaddrs(&ifa); - strlcpy(szIface, ifa->ifa_name, iflen); - freeifaddrs(ifa); - return 0; -} +THIS SOFTWARE IS PROVIDED BY AITNET 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 REGENTS 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 "global.h" + /* * io_etherClose() - Close BPF interface * @@ -32,7 +56,7 @@ io_get1stiface(char *szIface, int iflen) void io_etherClose(int eth, void **zcbuf) { -#ifdef __FreeBSD__ +#if defined(__FreeBSD__) && defined(ZCBUF_ENABLE) struct bpf_zbuf *zbuf = NULL; #endif @@ -40,7 +64,7 @@ io_etherClose(int eth, void **zcbuf) close(eth); if (zcbuf && *zcbuf) { -#ifdef __FreeBSD__ +#if defined(__FreeBSD__) && defined(ZCBUF_ENABLE) zbuf = *zcbuf; munmap(zbuf->bz_bufb, zbuf->bz_buflen); munmap(zbuf->bz_bufa, zbuf->bz_buflen); @@ -50,7 +74,7 @@ io_etherClose(int eth, void **zcbuf) } } -#ifdef __FreeBSD__ +#if defined(__FreeBSD__) && defined(ZCBUF_ENABLE) static inline struct bpf_zbuf * allocZCbuf(u_int len) { @@ -90,18 +114,28 @@ allocZCbuf(u_int len) * @csIface = interface name * @flags = open flags * @whdr = with complete headers + * @wdlt = with data link type * @buflen = buffer length * @zcbuf = zero copy buffer, if BPF supports it and isn't NULL * return: -1 error or >-1 bpf handle */ int -io_etherOpen(const char *csIface, int flags, int whdr, u_int *buflen, void **zcbuf) +io_etherOpen(const char *csIface, int flags, u_int whdr, u_int wdlt, + u_int *buflen, void **zcbuf) { - int n = 1, eth = -1; + int eth = -1; register int i; char szStr[STRSIZ]; struct ifreq ifr; + u_int n = 1; +#if !defined(__FreeBSD__) || !defined(ZCBUF_ENABLE) + if (zcbuf) { + io_SetErr(ENOTSUP, "bpf zero copy buffer mode is not supported"); + return -1; + } +#endif + for (i = 0; i < BPF_DEV_MAX; i++) { memset(szStr, 0, sizeof szStr); snprintf(szStr, sizeof szStr, "/dev/bpf%d", i); @@ -114,55 +148,69 @@ io_etherOpen(const char *csIface, int flags, int whdr, return -1; } - if (ioctl(eth, BIOCIMMEDIATE, &n) == -1) { - LOGERR; + if (csIface) + strlcpy(szStr, csIface, sizeof szStr); + else if (e_get1stiface(szStr, sizeof szStr) == -1) { close(eth); return -1; } + + n = 1; if (whdr && ioctl(eth, BIOCSHDRCMPLT, &n) == -1) { LOGERR; close(eth); return -1; } - if (buflen && *buflen) { - if (!zcbuf) { - if (ioctl(eth, BIOCSBLEN, buflen) == -1) { - LOGERR; - close(eth); - return -1; - } - } else { -#ifdef __FreeBSD__ - n = BPF_BUFMODE_ZBUF; - if (ioctl(eth, BIOCSETBUFMODE, &n) == -1) { - LOGERR; - close(eth); - return -1; - } - if (ioctl(eth, BIOCGETZMAX, &n) == -1) { - LOGERR; - close(eth); - return -1; - } else - *buflen = MIN(n, *buflen); - if (!(*zcbuf = allocZCbuf(*buflen))) { - close(eth); - return -1; - } - if (ioctl(eth, BIOCSETZBUF, (struct bpf_zbuf*) *zcbuf) == -1) { - LOGERR; - io_etherClose(eth, zcbuf); - return -1; - } -#endif - } - } - if (csIface) - strlcpy(szStr, csIface, sizeof szStr); - else if (io_get1stiface(szStr, sizeof szStr) == -1) { - io_etherClose(eth, zcbuf); + if (ioctl(eth, BIOCIMMEDIATE, &n) == -1) { + LOGERR; + close(eth); return -1; } + + if (!zcbuf) { + if (ioctl(eth, BIOCGBLEN, &n) == -1) { + LOGERR; + close(eth); + return -1; + } else + n = (buflen && *buflen) ? *buflen : getpagesize(); + + if (ioctl(eth, BIOCSBLEN, &n) == -1) { + LOGERR; + close(eth); + return -1; + } + if (buflen) + *buflen = n; + } else { +#if defined(__FreeBSD__) && defined(ZCBUF_ENABLE) + n = BPF_BUFMODE_ZBUF; + if (ioctl(eth, BIOCSETBUFMODE, &n) == -1) { + LOGERR; + close(eth); + return -1; + } + if (ioctl(eth, BIOCGETZMAX, &n) == -1) { + LOGERR; + close(eth); + return -1; + } else + n = (buflen && *buflen) ? *buflen : n; + if (!(*zcbuf = allocZCbuf(n))) { + close(eth); + return -1; + } + if (ioctl(eth, BIOCSETZBUF, *zcbuf) == -1) { + LOGERR; + io_etherClose(eth, zcbuf); + return -1; + } + if (buflen && *buflen) + *buflen = n; +#endif + } + + memset(&ifr, 0, sizeof ifr); strlcpy(ifr.ifr_name, szStr, sizeof ifr.ifr_name); if (ioctl(eth, BIOCSETIF, &ifr) == -1) { LOGERR; @@ -170,6 +218,13 @@ io_etherOpen(const char *csIface, int flags, int whdr, return -1; } + n = wdlt; + if (wdlt && ioctl(eth, BIOCSDLT, &n) == -1) { + LOGERR; + close(eth); + return -1; + } + return eth; } @@ -197,32 +252,48 @@ io_etherSend(int eth, const void *buf, size_t buflen) return wlen; } -#ifdef __FreeBSD__ -static inline ssize_t -nextZCbuf(void ** __restrict zcache, struct bpf_zbuf * __restrict zbuf, - const void * __restrict buf) +#if defined(__FreeBSD__) && defined(ZCBUF_ENABLE) +static inline void +ackZCbuf(struct bpf_zbuf_header *bzh) { - ssize_t rlen = -1; + atomic_store_rel_int(&bzh->bzh_user_gen, bzh->bzh_kernel_gen); +} + +static inline int +chkZCbuf(struct bpf_zbuf_header *bzh) +{ + /* return true if userspace owns buffer, and false otherwise. */ + return (bzh->bzh_user_gen != atomic_load_acq_int(&bzh->bzh_kernel_gen)); +} + +static ssize_t +nextZCbuf(int eth, struct bpf_zbuf * __restrict zbuf, void * __restrict buf, size_t buflen) +{ + ssize_t rlen = 0; + struct bpf_zbuf bz; struct bpf_zbuf_header *bzh; + off_t pos = 0; - if (!*zcache || *zcache == zbuf->bz_bufb) { - bzh = (struct bpf_zbuf_header *) zbuf->bz_bufa; - if (bzh->bzh_user_gen != atomic_load_acq_int(&bzh->bzh_kernel_gen)) { - rlen = atomic_load_acq_int(&bzh->bzh_kernel_len); - *zcache = zbuf->bz_bufa; - if (buf) - buf = ((caddr_t) *zcache) + sizeof(struct bpf_zbuf_header); - } - } else if (*zcache == zbuf->bz_bufa) { - bzh = (struct bpf_zbuf_header *) zbuf->bz_bufb; - if (bzh->bzh_user_gen != atomic_load_acq_int(&bzh->bzh_kernel_gen)) { - rlen = atomic_load_acq_int(&bzh->bzh_kernel_len); - *zcache = zbuf->bz_bufb; - if (buf) - buf = ((caddr_t) *zcache) + sizeof(struct bpf_zbuf_header); - } + bzh = (struct bpf_zbuf_header *) zbuf->bz_bufa; + if (chkZCbuf(bzh)) { + rlen = MIN(atomic_load_acq_int(&bzh->bzh_kernel_len), buflen); + memcpy(buf + pos, zbuf->bz_bufa + sizeof(struct bpf_zbuf_header), rlen); + ackZCbuf(bzh); + pos += rlen; } + bzh = (struct bpf_zbuf_header *) zbuf->bz_bufb; + if (chkZCbuf(bzh)) { + rlen = MIN(atomic_load_acq_int(&bzh->bzh_kernel_len), buflen); + memcpy(buf + pos, zbuf->bz_bufb + sizeof(struct bpf_zbuf_header), rlen); + ackZCbuf(bzh); + pos += rlen; + } + if (!pos) { + if ((rlen = ioctl(eth, BIOCROTZBUF, &bz)) == -1) + LOGERR; + } else + rlen = pos; return rlen; } #endif @@ -240,7 +311,7 @@ ssize_t io_etherRecv(int eth, void * __restrict buf, size_t buflen, void * __restrict zcbuf) { ssize_t rlen = 0; - void **zcache = NULL; + struct bpf_hdr *h; if (!buf || !buflen) { io_SetErr(EINVAL, "invalid arguments"); @@ -249,15 +320,83 @@ io_etherRecv(int eth, void * __restrict buf, size_t bu if (!zcbuf) { rlen = read(eth, buf, buflen); - if (rlen == -1) + if (rlen == -1) { LOGERR; + return -1; + } } else { -#ifdef __FreeBSD__ - rlen = nextZCbuf(zcache, (struct bpf_zbuf*) zcbuf, buf); +#if defined(__FreeBSD__) && defined(ZCBUF_ENABLE) + rlen = nextZCbuf(eth, (struct bpf_zbuf*) zcbuf, buf, buflen); + if (!rlen) + rlen = nextZCbuf(eth, (struct bpf_zbuf*) zcbuf, buf, buflen); #else + rlen = -1; io_SetErr(ENOTSUP, "bpf zero copy buffer mode is not supported"); #endif } + h = (struct bpf_hdr*) buf; + rlen -= h->bh_hdrlen; + + if (h->bh_caplen != rlen) { + if (h->bh_caplen < rlen) + rlen = h->bh_caplen; + else { + io_SetErr(EIO, "Captured %d bytes should be at most %d bytes", + h->bh_caplen, rlen); + return -1; + } + } + + memmove(buf, buf + h->bh_hdrlen, rlen); return rlen; } + +#ifndef __linux__ +/* + * io_etherFilter() - BPF filter routine + * + * @eth = bpf handle + * @io = filter direction + * (IO_ETHER_FILTER_PROMISC|IO_ETHER_FILTER_NOTREAD|IO_ETHER_FILTER_READ|IO_ETHER_FILTER_WRITE) + * @insn = BPF filter instruction array + * @insnlen = Length of BPF filter instruction array + * return: -1 error or 0 ok + */ +int +io_etherFilter(int eth, int io, struct bpf_insn * __restrict insn, size_t insnlen) +{ + int ret = 0; + struct bpf_program fcode = { 0 }; + + if (io != IO_ETHER_FILTER_PROMISC && (!insn || !insnlen)) { + io_SetErr(EINVAL, "invalid arguments"); + return -1; + } + + switch (io) { + case IO_ETHER_FILTER_PROMISC: /* promiscuous mode */ + ret = ioctl(eth, BIOCPROMISC, NULL); + break; + case IO_ETHER_FILTER_NOTREAD: /* read not filter */ + fcode.bf_len = insnlen / sizeof(struct bpf_insn); + fcode.bf_insns = insn; + ret = ioctl(eth, BIOCSETFNR, &fcode); + break; + case IO_ETHER_FILTER_READ: /* read filter */ + fcode.bf_len = insnlen / sizeof(struct bpf_insn); + fcode.bf_insns = insn; + ret = ioctl(eth, BIOCSETF, &fcode); + break; + case IO_ETHER_FILTER_WRITE: /* write filter */ + fcode.bf_len = insnlen / sizeof(struct bpf_insn); + fcode.bf_insns = insn; + ret = ioctl(eth, BIOCSETWF, &fcode); + break; + } + + if (ret == -1) + LOGERR; + return ret; +} +#endif