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author | Brian Somers <brian@FreeBSD.org> | 1997-08-25 00:29:32 +0000 |
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committer | Brian Somers <brian@FreeBSD.org> | 1997-08-25 00:29:32 +0000 |
commit | 944f709824ad3bd24c8318843a65198f6ef36c85 (patch) | |
tree | 462e956d74fef28e32846916ec1a402792684dc4 /usr.sbin/ppp/slcompress.c | |
parent | 30761f8783061e89a32aa2109678f3cfa65cbaac (diff) | |
download | src-944f709824ad3bd24c8318843a65198f6ef36c85.tar.gz src-944f709824ad3bd24c8318843a65198f6ef36c85.zip |
Make the code format more in line with style(9).
Update loadalias to use the new libalias api.
Update to version 1.1.
Notes
Notes:
svn path=/head/; revision=28679
Diffstat (limited to 'usr.sbin/ppp/slcompress.c')
-rw-r--r-- | usr.sbin/ppp/slcompress.c | 895 |
1 files changed, 449 insertions, 446 deletions
diff --git a/usr.sbin/ppp/slcompress.c b/usr.sbin/ppp/slcompress.c index 39babc98c31b..77aaa6f09133 100644 --- a/usr.sbin/ppp/slcompress.c +++ b/usr.sbin/ppp/slcompress.c @@ -17,13 +17,14 @@ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. * - * $Id: slcompress.c,v 1.8 1997/02/22 16:10:54 peter Exp $ + * $Id: slcompress.c,v 1.9 1997/06/09 03:27:37 brian Exp $ * * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989: * - Initial distribution. */ #ifndef lint -static char const rcsid[] = "$Id: slcompress.c,v 1.8 1997/02/22 16:10:54 peter Exp $"; +static char const rcsid[] = "$Id: slcompress.c,v 1.9 1997/06/09 03:27:37 brian Exp $"; + #endif #include "defs.h" @@ -46,23 +47,22 @@ struct slstat slstat; #endif void -sl_compress_init(comp) - struct slcompress *comp; +sl_compress_init(struct slcompress * comp) { - register u_int i; - register struct cstate *tstate = comp->tstate; - - bzero((char *)comp, sizeof(*comp)); - for (i = MAX_STATES - 1; i > 0; --i) { - tstate[i].cs_id = i; - tstate[i].cs_next = &tstate[i - 1]; - } - tstate[0].cs_next = &tstate[MAX_STATES - 1]; - tstate[0].cs_id = 0; - comp->last_cs = &tstate[0]; - comp->last_recv = 255; - comp->last_xmit = 255; - comp->flags = SLF_TOSS; + register u_int i; + register struct cstate *tstate = comp->tstate; + + bzero((char *) comp, sizeof(*comp)); + for (i = MAX_STATES - 1; i > 0; --i) { + tstate[i].cs_id = i; + tstate[i].cs_next = &tstate[i - 1]; + } + tstate[0].cs_next = &tstate[MAX_STATES - 1]; + tstate[0].cs_id = 0; + comp->last_cs = &tstate[0]; + comp->last_recv = 255; + comp->last_xmit = 255; + comp->flags = SLF_TOSS; } @@ -120,446 +120,449 @@ sl_compress_init(comp) u_char -sl_compress_tcp(m, ip, comp, compress_cid) - struct mbuf *m; - register struct ip *ip; - struct slcompress *comp; - int compress_cid; +sl_compress_tcp(struct mbuf * m, + struct ip * ip, + struct slcompress * comp, + int compress_cid) { - register struct cstate *cs = comp->last_cs->cs_next; - register u_int hlen = ip->ip_hl; - register struct tcphdr *oth; - register struct tcphdr *th; - register u_int deltaS, deltaA; - register u_int changes = 0; - u_char new_seq[16]; - register u_char *cp = new_seq; - - /* - * Bail if this is an IP fragment or if the TCP packet isn't - * `compressible' (i.e., ACK isn't set or some other control bit is - * set). (We assume that the caller has already made sure the - * packet is IP proto TCP). - */ - if ((ip->ip_off & htons(0x3fff)) || m->cnt < 40) { - LogPrintf(LogDEBUG, "??? 1 ip_off = %x, cnt = %d\n", - ip->ip_off, m->cnt); - LogDumpBp(LogDEBUG, "", m); - return (TYPE_IP); - } - - th = (struct tcphdr *)&((int *)ip)[hlen]; - if ((th->th_flags & (TH_SYN|TH_FIN|TH_RST|TH_ACK)) != TH_ACK) { - LogPrintf(LogDEBUG, "??? 2 th_flags = %x\n", th->th_flags); - LogDumpBp(LogDEBUG, "", m); - return (TYPE_IP); - } - - /* - * Packet is compressible -- we're going to send either a - * COMPRESSED_TCP or UNCOMPRESSED_TCP packet. Either way we need - * to locate (or create) the connection state. Special case the - * most recently used connection since it's most likely to be used - * again & we don't have to do any reordering if it's used. - */ - INCR(sls_packets) - if (ip->ip_src.s_addr != cs->cs_ip.ip_src.s_addr || - ip->ip_dst.s_addr != cs->cs_ip.ip_dst.s_addr || - *(int *)th != ((int *)&cs->cs_ip)[cs->cs_ip.ip_hl]) { - /* - * Wasn't the first -- search for it. - * - * States are kept in a circularly linked list with - * last_cs pointing to the end of the list. The - * list is kept in lru order by moving a state to the - * head of the list whenever it is referenced. Since - * the list is short and, empirically, the connection - * we want is almost always near the front, we locate - * states via linear search. If we don't find a state - * for the datagram, the oldest state is (re-)used. - */ - register struct cstate *lcs; - register struct cstate *lastcs = comp->last_cs; - - do { - lcs = cs; cs = cs->cs_next; - INCR(sls_searches) - if (ip->ip_src.s_addr == cs->cs_ip.ip_src.s_addr - && ip->ip_dst.s_addr == cs->cs_ip.ip_dst.s_addr - && *(int *)th == ((int *)&cs->cs_ip)[cs->cs_ip.ip_hl]) - goto found; - } while (cs != lastcs); - - /* - * Didn't find it -- re-use oldest cstate. Send an - * uncompressed packet that tells the other side what - * connection number we're using for this conversation. - * Note that since the state list is circular, the oldest - * state points to the newest and we only need to set - * last_cs to update the lru linkage. - */ - INCR(sls_misses) - comp->last_cs = lcs; + register struct cstate *cs = comp->last_cs->cs_next; + register u_int hlen = ip->ip_hl; + register struct tcphdr *oth; + register struct tcphdr *th; + register u_int deltaS, deltaA; + register u_int changes = 0; + u_char new_seq[16]; + register u_char *cp = new_seq; + + /* + * Bail if this is an IP fragment or if the TCP packet isn't `compressible' + * (i.e., ACK isn't set or some other control bit is set). (We assume that + * the caller has already made sure the packet is IP proto TCP). + */ + if ((ip->ip_off & htons(0x3fff)) || m->cnt < 40) { + LogPrintf(LogDEBUG, "??? 1 ip_off = %x, cnt = %d\n", + ip->ip_off, m->cnt); + LogDumpBp(LogDEBUG, "", m); + return (TYPE_IP); + } + th = (struct tcphdr *) & ((int *) ip)[hlen]; + if ((th->th_flags & (TH_SYN | TH_FIN | TH_RST | TH_ACK)) != TH_ACK) { + LogPrintf(LogDEBUG, "??? 2 th_flags = %x\n", th->th_flags); + LogDumpBp(LogDEBUG, "", m); + return (TYPE_IP); + } + + /* + * Packet is compressible -- we're going to send either a COMPRESSED_TCP or + * UNCOMPRESSED_TCP packet. Either way we need to locate (or create) the + * connection state. Special case the most recently used connection since + * it's most likely to be used again & we don't have to do any reordering + * if it's used. + */ + INCR(sls_packets) + if (ip->ip_src.s_addr != cs->cs_ip.ip_src.s_addr || + ip->ip_dst.s_addr != cs->cs_ip.ip_dst.s_addr || + *(int *) th != ((int *) &cs->cs_ip)[cs->cs_ip.ip_hl]) { + + /* + * Wasn't the first -- search for it. + * + * States are kept in a circularly linked list with last_cs pointing to the + * end of the list. The list is kept in lru order by moving a state to + * the head of the list whenever it is referenced. Since the list is + * short and, empirically, the connection we want is almost always near + * the front, we locate states via linear search. If we don't find a + * state for the datagram, the oldest state is (re-)used. + */ + register struct cstate *lcs; + register struct cstate *lastcs = comp->last_cs; + + do { + lcs = cs; + cs = cs->cs_next; + INCR(sls_searches) + if (ip->ip_src.s_addr == cs->cs_ip.ip_src.s_addr + && ip->ip_dst.s_addr == cs->cs_ip.ip_dst.s_addr + && *(int *) th == ((int *) &cs->cs_ip)[cs->cs_ip.ip_hl]) + goto found; + } while (cs != lastcs); + + /* + * Didn't find it -- re-use oldest cstate. Send an uncompressed packet + * that tells the other side what connection number we're using for this + * conversation. Note that since the state list is circular, the oldest + * state points to the newest and we only need to set last_cs to update + * the lru linkage. + */ + INCR(sls_misses) + comp->last_cs = lcs; #define THOFFSET(th) (th->th_off) - hlen += th->th_off; - hlen <<= 2; - if (hlen > m->cnt) - return(TYPE_IP); - goto uncompressed; - - found: - /* - * Found it -- move to the front on the connection list. - */ - if (cs == lastcs) - comp->last_cs = lcs; - else { - lcs->cs_next = cs->cs_next; - cs->cs_next = lastcs->cs_next; - lastcs->cs_next = cs; - } - } - - /* - * Make sure that only what we expect to change changed. The first - * line of the `if' checks the IP protocol version, header length & - * type of service. The 2nd line checks the "Don't fragment" bit. - * The 3rd line checks the time-to-live and protocol (the protocol - * check is unnecessary but costless). The 4th line checks the TCP - * header length. The 5th line checks IP options, if any. The 6th - * line checks TCP options, if any. If any of these things are - * different between the previous & current datagram, we send the - * current datagram `uncompressed'. - */ - oth = (struct tcphdr *)&((int *)&cs->cs_ip)[hlen]; - deltaS = hlen; - hlen += th->th_off; - hlen <<= 2; - if (hlen > m->cnt) - return(TYPE_IP); - - if (((u_short *)ip)[0] != ((u_short *)&cs->cs_ip)[0] || - ((u_short *)ip)[3] != ((u_short *)&cs->cs_ip)[3] || - ((u_short *)ip)[4] != ((u_short *)&cs->cs_ip)[4] || - THOFFSET(th) != THOFFSET(oth) || - (deltaS > 5 && - BCMP(ip + 1, &cs->cs_ip + 1, (deltaS - 5) << 2)) || - (THOFFSET(th) > 5 && - BCMP(th + 1, oth + 1, (THOFFSET(th) - 5) << 2))) { - goto uncompressed; - } - - /* - * Figure out which of the changing fields changed. The - * receiver expects changes in the order: urgent, window, - * ack, seq (the order minimizes the number of temporaries - * needed in this section of code). - */ - if (th->th_flags & TH_URG) { - deltaS = ntohs(th->th_urp); - ENCODEZ(deltaS); - changes |= NEW_U; - } else if (th->th_urp != oth->th_urp) { - /* argh! URG not set but urp changed -- a sensible - * implementation should never do this but RFC793 - * doesn't prohibit the change so we have to deal - * with it. */ - goto uncompressed; - } - - deltaS = (u_short)(ntohs(th->th_win) - ntohs(oth->th_win)); - if (deltaS) { - ENCODE(deltaS); - changes |= NEW_W; - } - - deltaA = ntohl(th->th_ack) - ntohl(oth->th_ack); - if (deltaA) { - if (deltaA > 0xffff) { - goto uncompressed; - } - ENCODE(deltaA); - changes |= NEW_A; - } - - deltaS = ntohl(th->th_seq) - ntohl(oth->th_seq); - if (deltaS) { - if (deltaS > 0xffff) { - goto uncompressed; - } - ENCODE(deltaS); - changes |= NEW_S; - } - - switch(changes) { - - case 0: - /* - * Nothing changed. If this packet contains data and the - * last one didn't, this is probably a data packet following - * an ack (normal on an interactive connection) and we send - * it compressed. Otherwise it's probably a retransmit, - * retransmitted ack or window probe. Send it uncompressed - * in case the other side missed the compressed version. - */ - if (ip->ip_len != cs->cs_ip.ip_len && - ntohs(cs->cs_ip.ip_len) == hlen) - break; - - /* (fall through) */ - - case SPECIAL_I: - case SPECIAL_D: - /* - * actual changes match one of our special case encodings -- - * send packet uncompressed. - */ - goto uncompressed; - - case NEW_S|NEW_A: - if (deltaS == deltaA && - deltaS == ntohs(cs->cs_ip.ip_len) - hlen) { - /* special case for echoed terminal traffic */ - changes = SPECIAL_I; - cp = new_seq; - } - break; - - case NEW_S: - if (deltaS == ntohs(cs->cs_ip.ip_len) - hlen) { - /* special case for data xfer */ - changes = SPECIAL_D; - cp = new_seq; - } - break; - } - - deltaS = ntohs(ip->ip_id) - ntohs(cs->cs_ip.ip_id); - if (deltaS != 1) { - ENCODEZ(deltaS); - changes |= NEW_I; - } - if (th->th_flags & TH_PUSH) - changes |= TCP_PUSH_BIT; - /* - * Grab the cksum before we overwrite it below. Then update our - * state with this packet's header. - */ - deltaA = ntohs(th->th_sum); - BCOPY(ip, &cs->cs_ip, hlen); - - /* - * We want to use the original packet as our compressed packet. - * (cp - new_seq) is the number of bytes we need for compressed - * sequence numbers. In addition we need one byte for the change - * mask, one for the connection id and two for the tcp checksum. - * So, (cp - new_seq) + 4 bytes of header are needed. hlen is how - * many bytes of the original packet to toss so subtract the two to - * get the new packet size. - */ - deltaS = cp - new_seq; - cp = (u_char *)ip; - - /* - * Since fastq traffic can jump ahead of the background traffic, - * we don't know what order packets will go on the line. In this - * case, we always send a "new" connection id so the receiver state - * stays synchronized. - */ + hlen += th->th_off; + hlen <<= 2; + if (hlen > m->cnt) + return (TYPE_IP); + goto uncompressed; + +found: + + /* + * Found it -- move to the front on the connection list. + */ + if (cs == lastcs) + comp->last_cs = lcs; + else { + lcs->cs_next = cs->cs_next; + cs->cs_next = lastcs->cs_next; + lastcs->cs_next = cs; + } + } + + /* + * Make sure that only what we expect to change changed. The first line of + * the `if' checks the IP protocol version, header length & type of + * service. The 2nd line checks the "Don't fragment" bit. The 3rd line + * checks the time-to-live and protocol (the protocol check is unnecessary + * but costless). The 4th line checks the TCP header length. The 5th line + * checks IP options, if any. The 6th line checks TCP options, if any. If + * any of these things are different between the previous & current + * datagram, we send the current datagram `uncompressed'. + */ + oth = (struct tcphdr *) & ((int *) &cs->cs_ip)[hlen]; + deltaS = hlen; + hlen += th->th_off; + hlen <<= 2; + if (hlen > m->cnt) + return (TYPE_IP); + + if (((u_short *) ip)[0] != ((u_short *) & cs->cs_ip)[0] || + ((u_short *) ip)[3] != ((u_short *) & cs->cs_ip)[3] || + ((u_short *) ip)[4] != ((u_short *) & cs->cs_ip)[4] || + THOFFSET(th) != THOFFSET(oth) || + (deltaS > 5 && + BCMP(ip + 1, &cs->cs_ip + 1, (deltaS - 5) << 2)) || + (THOFFSET(th) > 5 && + BCMP(th + 1, oth + 1, (THOFFSET(th) - 5) << 2))) { + goto uncompressed; + } + + /* + * Figure out which of the changing fields changed. The receiver expects + * changes in the order: urgent, window, ack, seq (the order minimizes the + * number of temporaries needed in this section of code). + */ + if (th->th_flags & TH_URG) { + deltaS = ntohs(th->th_urp); + ENCODEZ(deltaS); + changes |= NEW_U; + } else if (th->th_urp != oth->th_urp) { + + /* + * argh! URG not set but urp changed -- a sensible implementation should + * never do this but RFC793 doesn't prohibit the change so we have to + * deal with it. + */ + goto uncompressed; + } + deltaS = (u_short) (ntohs(th->th_win) - ntohs(oth->th_win)); + if (deltaS) { + ENCODE(deltaS); + changes |= NEW_W; + } + deltaA = ntohl(th->th_ack) - ntohl(oth->th_ack); + if (deltaA) { + if (deltaA > 0xffff) { + goto uncompressed; + } + ENCODE(deltaA); + changes |= NEW_A; + } + deltaS = ntohl(th->th_seq) - ntohl(oth->th_seq); + if (deltaS) { + if (deltaS > 0xffff) { + goto uncompressed; + } + ENCODE(deltaS); + changes |= NEW_S; + } + switch (changes) { + + case 0: + + /* + * Nothing changed. If this packet contains data and the last one didn't, + * this is probably a data packet following an ack (normal on an + * interactive connection) and we send it compressed. Otherwise it's + * probably a retransmit, retransmitted ack or window probe. Send it + * uncompressed in case the other side missed the compressed version. + */ + if (ip->ip_len != cs->cs_ip.ip_len && + ntohs(cs->cs_ip.ip_len) == hlen) + break; + + /* (fall through) */ + + case SPECIAL_I: + case SPECIAL_D: + + /* + * actual changes match one of our special case encodings -- send packet + * uncompressed. + */ + goto uncompressed; + + case NEW_S | NEW_A: + if (deltaS == deltaA && + deltaS == ntohs(cs->cs_ip.ip_len) - hlen) { + /* special case for echoed terminal traffic */ + changes = SPECIAL_I; + cp = new_seq; + } + break; + + case NEW_S: + if (deltaS == ntohs(cs->cs_ip.ip_len) - hlen) { + /* special case for data xfer */ + changes = SPECIAL_D; + cp = new_seq; + } + break; + } + + deltaS = ntohs(ip->ip_id) - ntohs(cs->cs_ip.ip_id); + if (deltaS != 1) { + ENCODEZ(deltaS); + changes |= NEW_I; + } + if (th->th_flags & TH_PUSH) + changes |= TCP_PUSH_BIT; + + /* + * Grab the cksum before we overwrite it below. Then update our state with + * this packet's header. + */ + deltaA = ntohs(th->th_sum); + BCOPY(ip, &cs->cs_ip, hlen); + + /* + * We want to use the original packet as our compressed packet. (cp - + * new_seq) is the number of bytes we need for compressed sequence numbers. + * In addition we need one byte for the change mask, one for the connection + * id and two for the tcp checksum. So, (cp - new_seq) + 4 bytes of header + * are needed. hlen is how many bytes of the original packet to toss so + * subtract the two to get the new packet size. + */ + deltaS = cp - new_seq; + cp = (u_char *) ip; + + /* + * Since fastq traffic can jump ahead of the background traffic, we don't + * know what order packets will go on the line. In this case, we always + * send a "new" connection id so the receiver state stays synchronized. + */ #ifdef SL_NOFASTQ - if (comp->last_xmit == cs->cs_id) { - hlen -= deltaS + 3; - cp += hlen; - *cp++ = changes; - } else + if (comp->last_xmit == cs->cs_id) { + hlen -= deltaS + 3; + cp += hlen; + *cp++ = changes; + } else #endif - { - comp->last_xmit = cs->cs_id; - hlen -= deltaS + 4; - cp += hlen; - *cp++ = changes | NEW_C; - *cp++ = cs->cs_id; - } - m->cnt -= hlen; - m->offset += hlen; - *cp++ = deltaA >> 8; - *cp++ = deltaA; - BCOPY(new_seq, cp, deltaS); - INCR(sls_compressed) - return (TYPE_COMPRESSED_TCP); - - /* - * Update connection state cs & send uncompressed packet ('uncompressed' - * means a regular ip/tcp packet but with the 'conversation id' we hope - * to use on future compressed packets in the protocol field). - */ + { + comp->last_xmit = cs->cs_id; + hlen -= deltaS + 4; + cp += hlen; + *cp++ = changes | NEW_C; + *cp++ = cs->cs_id; + } + m->cnt -= hlen; + m->offset += hlen; + *cp++ = deltaA >> 8; + *cp++ = deltaA; + BCOPY(new_seq, cp, deltaS); + INCR(sls_compressed) + return (TYPE_COMPRESSED_TCP); + + /* + * Update connection state cs & send uncompressed packet ('uncompressed' + * means a regular ip/tcp packet but with the 'conversation id' we hope to + * use on future compressed packets in the protocol field). + */ uncompressed: - BCOPY(ip, &cs->cs_ip, hlen); - ip->ip_p = cs->cs_id; - comp->last_xmit = cs->cs_id; - return (TYPE_UNCOMPRESSED_TCP); + BCOPY(ip, &cs->cs_ip, hlen); + ip->ip_p = cs->cs_id; + comp->last_xmit = cs->cs_id; + return (TYPE_UNCOMPRESSED_TCP); } int -sl_uncompress_tcp(bufp, len, type, comp) - u_char **bufp; - int len; - u_int type; - struct slcompress *comp; +sl_uncompress_tcp(u_char ** bufp, + int len, + u_int type, + struct slcompress * comp) { - register u_char *cp; - register u_int hlen, changes; - register struct tcphdr *th; - register struct cstate *cs; - register struct ip *ip; - - switch (type) { - - case TYPE_UNCOMPRESSED_TCP: - ip = (struct ip *) *bufp; - if (ip->ip_p >= MAX_STATES) - goto bad; - cs = &comp->rstate[comp->last_recv = ip->ip_p]; - comp->flags &=~ SLF_TOSS; - ip->ip_p = IPPROTO_TCP; - /* - * Calculate the size of the TCP/IP header and make sure that - * we don't overflow the space we have available for it. - */ - hlen = ip->ip_hl << 2; - if (hlen + sizeof(struct tcphdr) > len) - goto bad; - th = (struct tcphdr *)&((char *)ip)[hlen]; - hlen += THOFFSET(th) << 2; - if (hlen > MAX_HDR) - goto bad; - BCOPY(ip, &cs->cs_ip, hlen); - cs->cs_ip.ip_sum = 0; - cs->cs_hlen = hlen; - INCR(sls_uncompressedin) - return (len); - - default: - goto bad; - - case TYPE_COMPRESSED_TCP: - break; - } - /* We've got a compressed packet. */ - INCR(sls_compressedin) - cp = *bufp; - changes = *cp++; - LogPrintf(LogDEBUG, "compressed: changes = %02x\n", changes); - if (changes & NEW_C) { - /* Make sure the state index is in range, then grab the state. - * If we have a good state index, clear the 'discard' flag. */ - if (*cp >= MAX_STATES || comp->last_recv == 255) - goto bad; - - comp->flags &=~ SLF_TOSS; - comp->last_recv = *cp++; - } else { - /* this packet has an implicit state index. If we've - * had a line error since the last time we got an - * explicit state index, we have to toss the packet. */ - if (comp->flags & SLF_TOSS) { - INCR(sls_tossed) - return (0); - } - } - cs = &comp->rstate[comp->last_recv]; - hlen = cs->cs_ip.ip_hl << 2; - th = (struct tcphdr *)&((u_char *)&cs->cs_ip)[hlen]; - th->th_sum = htons((*cp << 8) | cp[1]); - cp += 2; - if (changes & TCP_PUSH_BIT) - th->th_flags |= TH_PUSH; - else - th->th_flags &=~ TH_PUSH; - - switch (changes & SPECIALS_MASK) { - case SPECIAL_I: - { - register u_int i = ntohs(cs->cs_ip.ip_len) - cs->cs_hlen; - th->th_ack = htonl(ntohl(th->th_ack) + i); - th->th_seq = htonl(ntohl(th->th_seq) + i); - } - break; - - case SPECIAL_D: - th->th_seq = htonl(ntohl(th->th_seq) + ntohs(cs->cs_ip.ip_len) - - cs->cs_hlen); - break; - - default: - if (changes & NEW_U) { - th->th_flags |= TH_URG; - DECODEU(th->th_urp) - } else - th->th_flags &=~ TH_URG; - if (changes & NEW_W) - DECODES(th->th_win) - if (changes & NEW_A) - DECODEL(th->th_ack) - if (changes & NEW_S) { - LogPrintf(LogDEBUG, "NEW_S: %02x, %02x, %02x\n", - *cp, cp[1], cp[2]); - DECODEL(th->th_seq) - } - break; + register u_char *cp; + register u_int hlen, changes; + register struct tcphdr *th; + register struct cstate *cs; + register struct ip *ip; + + switch (type) { + + case TYPE_UNCOMPRESSED_TCP: + ip = (struct ip *) * bufp; + if (ip->ip_p >= MAX_STATES) + goto bad; + cs = &comp->rstate[comp->last_recv = ip->ip_p]; + comp->flags &= ~SLF_TOSS; + ip->ip_p = IPPROTO_TCP; + + /* + * Calculate the size of the TCP/IP header and make sure that we don't + * overflow the space we have available for it. + */ + hlen = ip->ip_hl << 2; + if (hlen + sizeof(struct tcphdr) > len) + goto bad; + th = (struct tcphdr *) & ((char *) ip)[hlen]; + hlen += THOFFSET(th) << 2; + if (hlen > MAX_HDR) + goto bad; + BCOPY(ip, &cs->cs_ip, hlen); + cs->cs_ip.ip_sum = 0; + cs->cs_hlen = hlen; + INCR(sls_uncompressedin) + return (len); + + default: + goto bad; + + case TYPE_COMPRESSED_TCP: + break; + } + /* We've got a compressed packet. */ + INCR(sls_compressedin) + cp = *bufp; + changes = *cp++; + LogPrintf(LogDEBUG, "compressed: changes = %02x\n", changes); + if (changes & NEW_C) { + + /* + * Make sure the state index is in range, then grab the state. If we have + * a good state index, clear the 'discard' flag. + */ + if (*cp >= MAX_STATES || comp->last_recv == 255) + goto bad; + + comp->flags &= ~SLF_TOSS; + comp->last_recv = *cp++; + } else { + + /* + * this packet has an implicit state index. If we've had a line error + * since the last time we got an explicit state index, we have to toss + * the packet. + */ + if (comp->flags & SLF_TOSS) { + INCR(sls_tossed) + return (0); + } + } + cs = &comp->rstate[comp->last_recv]; + hlen = cs->cs_ip.ip_hl << 2; + th = (struct tcphdr *) & ((u_char *) & cs->cs_ip)[hlen]; + th->th_sum = htons((*cp << 8) | cp[1]); + cp += 2; + if (changes & TCP_PUSH_BIT) + th->th_flags |= TH_PUSH; + else + th->th_flags &= ~TH_PUSH; + + switch (changes & SPECIALS_MASK) { + case SPECIAL_I: + { + register u_int i = ntohs(cs->cs_ip.ip_len) - cs->cs_hlen; + + th->th_ack = htonl(ntohl(th->th_ack) + i); + th->th_seq = htonl(ntohl(th->th_seq) + i); + } + break; + + case SPECIAL_D: + th->th_seq = htonl(ntohl(th->th_seq) + ntohs(cs->cs_ip.ip_len) + - cs->cs_hlen); + break; + + default: + if (changes & NEW_U) { + th->th_flags |= TH_URG; + DECODEU(th->th_urp) + } else + th->th_flags &= ~TH_URG; + if (changes & NEW_W) + DECODES(th->th_win) + if (changes & NEW_A) + DECODEL(th->th_ack) + if (changes & NEW_S) { + LogPrintf(LogDEBUG, "NEW_S: %02x, %02x, %02x\n", + *cp, cp[1], cp[2]); + DECODEL(th->th_seq) } - if (changes & NEW_I) { - DECODES(cs->cs_ip.ip_id) - } else - cs->cs_ip.ip_id = htons(ntohs(cs->cs_ip.ip_id) + 1); - - LogPrintf(LogDEBUG, "Uncompress: id = %04x, seq = %08x\n", - cs->cs_ip.ip_id, ntohl(th->th_seq)); - - /* - * At this point, cp points to the first byte of data in the - * packet. If we're not aligned on a 4-byte boundary, copy the - * data down so the ip & tcp headers will be aligned. Then back up - * cp by the tcp/ip header length to make room for the reconstructed - * header (we assume the packet we were handed has enough space to - * prepend 128 bytes of header). Adjust the length to account for - * the new header & fill in the IP total length. - */ - len -= (cp - *bufp); - if (len < 0) - /* we must have dropped some characters (crc should detect - * this but the old slip framing won't) */ - goto bad; + break; + } + if (changes & NEW_I) { + DECODES(cs->cs_ip.ip_id) + } else + cs->cs_ip.ip_id = htons(ntohs(cs->cs_ip.ip_id) + 1); + + LogPrintf(LogDEBUG, "Uncompress: id = %04x, seq = %08x\n", + cs->cs_ip.ip_id, ntohl(th->th_seq)); + + /* + * At this point, cp points to the first byte of data in the packet. If + * we're not aligned on a 4-byte boundary, copy the data down so the ip & + * tcp headers will be aligned. Then back up cp by the tcp/ip header + * length to make room for the reconstructed header (we assume the packet + * we were handed has enough space to prepend 128 bytes of header). Adjust + * the length to account for the new header & fill in the IP total length. + */ + len -= (cp - *bufp); + if (len < 0) + + /* + * we must have dropped some characters (crc should detect this but the + * old slip framing won't) + */ + goto bad; #ifdef notdef - if ((int)cp & 3) { - if (len > 0) - (void) ovbcopy(cp, (caddr_t)((int)cp &~ 3), len); - cp = (u_char *)((int)cp &~ 3); - } + if ((int) cp & 3) { + if (len > 0) + (void) ovbcopy(cp, (caddr_t) ((int) cp & ~3), len); + cp = (u_char *) ((int) cp & ~3); + } #endif - cp -= cs->cs_hlen; - len += cs->cs_hlen; - cs->cs_ip.ip_len = htons(len); - BCOPY(&cs->cs_ip, cp, cs->cs_hlen); - *bufp = cp; - - /* recompute the ip header checksum */ - { - register u_short *bp = (u_short *)cp; - for (changes = 0; hlen > 0; hlen -= 2) - changes += *bp++; - changes = (changes & 0xffff) + (changes >> 16); - changes = (changes & 0xffff) + (changes >> 16); - ((struct ip *)cp)->ip_sum = ~ changes; - } - return (len); + cp -= cs->cs_hlen; + len += cs->cs_hlen; + cs->cs_ip.ip_len = htons(len); + BCOPY(&cs->cs_ip, cp, cs->cs_hlen); + *bufp = cp; + + /* recompute the ip header checksum */ + { + register u_short *bp = (u_short *) cp; + + for (changes = 0; hlen > 0; hlen -= 2) + changes += *bp++; + changes = (changes & 0xffff) + (changes >> 16); + changes = (changes & 0xffff) + (changes >> 16); + ((struct ip *) cp)->ip_sum = ~changes; + } + return (len); bad: - comp->flags |= SLF_TOSS; - INCR(sls_errorin) - return (0); + comp->flags |= SLF_TOSS; + INCR(sls_errorin) + return (0); } int @@ -569,12 +572,12 @@ ReportCompress() return 1; fprintf(VarTerm, "Out: %d (compress) / %d (total)", - slstat.sls_compressed, slstat.sls_packets); + slstat.sls_compressed, slstat.sls_packets); fprintf(VarTerm, " %d (miss) / %d (search)\n", - slstat.sls_misses, slstat.sls_searches); + slstat.sls_misses, slstat.sls_searches); fprintf(VarTerm, "In: %d (compress), %d (uncompress)", - slstat.sls_compressedin, slstat.sls_uncompressedin); + slstat.sls_compressedin, slstat.sls_uncompressedin); fprintf(VarTerm, " %d (error), %d (tossed)\n", - slstat.sls_errorin, slstat.sls_tossed); + slstat.sls_errorin, slstat.sls_tossed); return 0; } |