diff options
Diffstat (limited to 'contrib/ipfilter/lib/ipft_pc.c')
| -rw-r--r-- | contrib/ipfilter/lib/ipft_pc.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/contrib/ipfilter/lib/ipft_pc.c b/contrib/ipfilter/lib/ipft_pc.c new file mode 100644 index 0000000..3a264bd --- /dev/null +++ b/contrib/ipfilter/lib/ipft_pc.c @@ -0,0 +1,254 @@ +/* $FreeBSD$ */ + +/* + * Copyright (C) 2012 by Darren Reed. + * + * See the IPFILTER.LICENCE file for details on licencing. + * + * $Id$ + */ +#include "ipf.h" +#include "ipt.h" + +#if !defined(lint) +static const char rcsid[] = "@(#)$Id$"; +#endif + +struct llc { + int lc_type; + int lc_sz; /* LLC header length */ + int lc_to; /* LLC Type offset */ + int lc_tl; /* LLC Type length */ +}; + +/* + * While many of these maybe the same, some do have different header formats + * which make this useful. + */ + +static struct llc llcs[] = { + { 0, 0, 0, 0 }, /* DLT_NULL */ + { 1, 14, 12, 2 }, /* DLT_Ethernet */ + { 10, 0, 0, 0 }, /* DLT_FDDI */ + { 12, 0, 0, 0 }, /* DLT_RAW */ + { -1, -1, -1, -1 } +}; + +typedef struct { + u_int id; + u_short major; + u_short minor; + u_int timezone; + u_int sigfigs; + u_int snaplen; + u_int type; +} fileheader_t; + +typedef struct { + u_32_t seconds; + u_32_t microseconds; + u_32_t caplen; + u_32_t wirelen; +} packetheader_t; + +static int ipcap_open __P((char *)); +static int ipcap_close __P((void)); +static int ipcap_readip __P((mb_t *, char **, int *)); +static int ipcap_read_rec __P((packetheader_t *)); +static void iswap_hdr __P((fileheader_t *)); + +static int pfd = -1, swapped = 0; +static struct llc *llcp = NULL; + +struct ipread pcap = { ipcap_open, ipcap_close, ipcap_readip, 0 }; + +#define SWAPLONG(y) \ + ((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff)) +#define SWAPSHORT(y) \ + ( (((y)&0xff)<<8) | (((y)&0xff00)>>8) ) + +static void iswap_hdr(p) + fileheader_t *p; +{ + p->major = SWAPSHORT(p->major); + p->minor = SWAPSHORT(p->minor); + p->timezone = SWAPLONG(p->timezone); + p->sigfigs = SWAPLONG(p->sigfigs); + p->snaplen = SWAPLONG(p->snaplen); + p->type = SWAPLONG(p->type); +} + +static int ipcap_open(fname) + char *fname; +{ + fileheader_t ph; + int fd, i; + + if (pfd != -1) + return pfd; + + if (!strcmp(fname, "-")) + fd = 0; + else if ((fd = open(fname, O_RDONLY)) == -1) + return -1; + + if (read(fd, (char *)&ph, sizeof(ph)) != sizeof(ph)) + return -2; + + if (ph.id != 0xa1b2c3d4) { + if (SWAPLONG(ph.id) != 0xa1b2c3d4) { + (void) close(fd); + return -2; + } + swapped = 1; + iswap_hdr(&ph); + } + + for (i = 0; llcs[i].lc_type != -1; i++) + if (llcs[i].lc_type == ph.type) { + llcp = llcs + i; + break; + } + + if (llcp == NULL) { + (void) close(fd); + return -2; + } + + pfd = fd; + printf("opened pcap file %s:\n", fname); + printf("\tid: %08x version: %d.%d type: %d snap %d\n", + ph.id, ph.major, ph.minor, ph.type, ph.snaplen); + + return fd; +} + + +static int ipcap_close() +{ + return close(pfd); +} + + +/* + * read in the header (and validate) which should be the first record + * in a pcap file. + */ +static int ipcap_read_rec(rec) + packetheader_t *rec; +{ + int n, p, i; + char *s; + + s = (char *)rec; + n = sizeof(*rec); + + while (n > 0) { + i = read(pfd, (char *)rec, sizeof(*rec)); + if (i <= 0) + return -2; + s += i; + n -= i; + } + + if (swapped) { + rec->caplen = SWAPLONG(rec->caplen); + rec->wirelen = SWAPLONG(rec->wirelen); + rec->seconds = SWAPLONG(rec->seconds); + rec->microseconds = SWAPLONG(rec->microseconds); + } + p = rec->caplen; + n = MIN(p, rec->wirelen); + if (!n || n < 0) + return -3; + + if (p < 0 || p > 65536) + return -4; + return p; +} + + +#ifdef notyet +/* + * read an entire pcap packet record. only the data part is copied into + * the available buffer, with the number of bytes copied returned. + */ +static int ipcap_read(buf, cnt) + char *buf; + int cnt; +{ + packetheader_t rec; + static char *bufp = NULL; + int i, n; + + if ((i = ipcap_read_rec(&rec)) <= 0) + return i; + + if (!bufp) + bufp = malloc(i); + else + bufp = realloc(bufp, i); + + if (read(pfd, bufp, i) != i) + return -2; + + n = MIN(i, cnt); + bcopy(bufp, buf, n); + return n; +} +#endif + + +/* + * return only an IP packet read into buf + */ +static int ipcap_readip(mb, ifn, dir) + mb_t *mb; + char **ifn; + int *dir; +{ + static char *bufp = NULL; + packetheader_t rec; + struct llc *l; + char *s, ty[4]; + int i, j, n; + char *buf; + int cnt; + +#if 0 + ifn = ifn; /* gcc -Wextra */ + dir = dir; /* gcc -Wextra */ +#endif + buf = (char *)mb->mb_buf; + cnt = sizeof(mb->mb_buf); + l = llcp; + + /* do { */ + if ((i = ipcap_read_rec(&rec)) <= 0) + return i; + + if (!bufp) + bufp = malloc(i); + else + bufp = realloc(bufp, i); + s = bufp; + + for (j = i, n = 0; j > 0; ) { + n = read(pfd, s, j); + if (n <= 0) + return -2; + j -= n; + s += n; + } + s = bufp; + + i -= l->lc_sz; + s += l->lc_to; + bcopy(s, ty, l->lc_tl); + s += l->lc_tl; + /* } while (ty[0] != 0x8 && ty[1] != 0); */ + n = MIN(i, cnt); + bcopy(s, buf, n); + mb->mb_len = n; + return n; +} |
