/* $OpenBSD: ccp.c,v 1.12 2003/04/04 20:25:07 deraadt Exp $ */ /* * ccp.c - PPP Compression Control Protocol. * * Copyright (c) 1989-2002 Paul Mackerras. 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. * * 3. The name(s) of the authors of this software must not be used to * endorse or promote products derived from this software without * prior written permission. * * 4. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by Paul Mackerras * ". * * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #ifndef lint #if 0 static char rcsid[] = "Id: ccp.c,v 1.22 1998/03/25 01:25:02 paulus Exp $"; #else static char rcsid[] = "$OpenBSD: ccp.c,v 1.12 2003/04/04 20:25:07 deraadt Exp $"; #endif #endif #include #include #include #include #include "pppd.h" #include "fsm.h" #include "ccp.h" #include /* * Protocol entry points from main code. */ static void ccp_init(int unit); static void ccp_open(int unit); static void ccp_close(int unit, char *); static void ccp_lowerup(int unit); static void ccp_lowerdown(int); static void ccp_input(int unit, u_char *pkt, int len); static void ccp_protrej(int unit); static int ccp_printpkt(u_char *pkt, int len, void (*printer)(void *, char *, ...), void *arg); static void ccp_datainput(int unit, u_char *pkt, int len); struct protent ccp_protent = { PPP_CCP, ccp_init, ccp_input, ccp_protrej, ccp_lowerup, ccp_lowerdown, ccp_open, ccp_close, ccp_printpkt, ccp_datainput, 1, "CCP", NULL, NULL, NULL }; fsm ccp_fsm[NUM_PPP]; ccp_options ccp_wantoptions[NUM_PPP]; /* what to request the peer to use */ ccp_options ccp_gotoptions[NUM_PPP]; /* what the peer agreed to do */ ccp_options ccp_allowoptions[NUM_PPP]; /* what we'll agree to do */ ccp_options ccp_hisoptions[NUM_PPP]; /* what we agreed to do */ /* * Callbacks for fsm code. */ static void ccp_resetci(fsm *); static int ccp_cilen(fsm *); static void ccp_addci(fsm *, u_char *, int *); static int ccp_ackci(fsm *, u_char *, int); static int ccp_nakci(fsm *, u_char *, int); static int ccp_rejci(fsm *, u_char *, int); static int ccp_reqci(fsm *, u_char *, int *, int); static void ccp_up(fsm *); static void ccp_down(fsm *); static int ccp_extcode(fsm *, int, int, u_char *, int); static void ccp_rack_timeout(void *); static char *method_name(ccp_options *, ccp_options *); static fsm_callbacks ccp_callbacks = { ccp_resetci, ccp_cilen, ccp_addci, ccp_ackci, ccp_nakci, ccp_rejci, ccp_reqci, ccp_up, ccp_down, NULL, NULL, NULL, NULL, ccp_extcode, "CCP" }; /* * Do we want / did we get any compression? */ #define ANY_COMPRESS(opt) ((opt).deflate || (opt).bsd_compress \ || (opt).predictor_1 || (opt).predictor_2) /* * Local state (mainly for handling reset-reqs and reset-acks). */ static int ccp_localstate[NUM_PPP]; #define RACK_PENDING 1 /* waiting for reset-ack */ #define RREQ_REPEAT 2 /* send another reset-req if no reset-ack */ #define RACKTIMEOUT 1 /* second */ static int all_rejected[NUM_PPP]; /* we rejected all peer's options */ /* * ccp_init - initialize CCP. */ static void ccp_init(unit) int unit; { fsm *f = &ccp_fsm[unit]; f->unit = unit; f->protocol = PPP_CCP; f->callbacks = &ccp_callbacks; fsm_init(f); memset(&ccp_wantoptions[unit], 0, sizeof(ccp_options)); memset(&ccp_gotoptions[unit], 0, sizeof(ccp_options)); memset(&ccp_allowoptions[unit], 0, sizeof(ccp_options)); memset(&ccp_hisoptions[unit], 0, sizeof(ccp_options)); ccp_wantoptions[0].deflate = 1; ccp_wantoptions[0].deflate_size = DEFLATE_MAX_SIZE; ccp_wantoptions[0].deflate_correct = 1; ccp_wantoptions[0].deflate_draft = 1; ccp_allowoptions[0].deflate = 1; ccp_allowoptions[0].deflate_size = DEFLATE_MAX_SIZE; ccp_allowoptions[0].deflate_correct = 1; ccp_allowoptions[0].deflate_draft = 1; ccp_wantoptions[0].bsd_compress = 1; ccp_wantoptions[0].bsd_bits = BSD_MAX_BITS; ccp_allowoptions[0].bsd_compress = 1; ccp_allowoptions[0].bsd_bits = BSD_MAX_BITS; ccp_allowoptions[0].predictor_1 = 1; } /* * ccp_open - CCP is allowed to come up. */ static void ccp_open(unit) int unit; { fsm *f = &ccp_fsm[unit]; if (f->state != OPENED) ccp_flags_set(unit, 1, 0); /* * Find out which compressors the kernel supports before * deciding whether to open in silent mode. */ ccp_resetci(f); if (!ANY_COMPRESS(ccp_gotoptions[unit])) f->flags |= OPT_SILENT; fsm_open(f); } /* * ccp_close - Terminate CCP. */ static void ccp_close(unit, reason) int unit; char *reason; { ccp_flags_set(unit, 0, 0); fsm_close(&ccp_fsm[unit], reason); } /* * ccp_lowerup - we may now transmit CCP packets. */ static void ccp_lowerup(unit) int unit; { fsm_lowerup(&ccp_fsm[unit]); } /* * ccp_lowerdown - we may not transmit CCP packets. */ static void ccp_lowerdown(unit) int unit; { fsm_lowerdown(&ccp_fsm[unit]); } /* * ccp_input - process a received CCP packet. */ static void ccp_input(unit, p, len) int unit; u_char *p; int len; { fsm *f = &ccp_fsm[unit]; int oldstate; /* * Check for a terminate-request so we can print a message. */ oldstate = f->state; fsm_input(f, p, len); if (oldstate == OPENED && p[0] == TERMREQ && f->state != OPENED) syslog(LOG_NOTICE, "Compression disabled by peer."); /* * If we get a terminate-ack and we're not asking for compression, * close CCP. */ if (oldstate == REQSENT && p[0] == TERMACK && !ANY_COMPRESS(ccp_gotoptions[unit])) ccp_close(unit, "No compression negotiated"); } /* * Handle a CCP-specific code. */ static int ccp_extcode(f, code, id, p, len) fsm *f; int code, id; u_char *p; int len; { switch (code) { case CCP_RESETREQ: if (f->state != OPENED) break; /* send a reset-ack, which the transmitter will see and reset its compression state. */ fsm_sdata(f, CCP_RESETACK, id, NULL, 0); break; case CCP_RESETACK: if (ccp_localstate[f->unit] & RACK_PENDING && id == f->reqid) { ccp_localstate[f->unit] &= ~(RACK_PENDING | RREQ_REPEAT); UNTIMEOUT(ccp_rack_timeout, f); } break; default: return 0; } return 1; } /* * ccp_protrej - peer doesn't talk CCP. */ static void ccp_protrej(unit) int unit; { ccp_flags_set(unit, 0, 0); fsm_lowerdown(&ccp_fsm[unit]); } /* * ccp_resetci - initialize at start of negotiation. */ static void ccp_resetci(f) fsm *f; { ccp_options *go = &ccp_gotoptions[f->unit]; u_char opt_buf[16]; *go = ccp_wantoptions[f->unit]; all_rejected[f->unit] = 0; /* * Check whether the kernel knows about the various * compression methods we might request. */ if (go->bsd_compress) { opt_buf[0] = CI_BSD_COMPRESS; opt_buf[1] = CILEN_BSD_COMPRESS; opt_buf[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, BSD_MIN_BITS); if (ccp_test(f->unit, opt_buf, CILEN_BSD_COMPRESS, 0) <= 0) go->bsd_compress = 0; } if (go->deflate) { if (go->deflate_correct) { opt_buf[0] = CI_DEFLATE; opt_buf[1] = CILEN_DEFLATE; opt_buf[2] = DEFLATE_MAKE_OPT(DEFLATE_MIN_SIZE); opt_buf[3] = DEFLATE_CHK_SEQUENCE; if (ccp_test(f->unit, opt_buf, CILEN_DEFLATE, 0) <= 0) go->deflate_correct = 0; } if (go->deflate_draft) { opt_buf[0] = CI_DEFLATE_DRAFT; opt_buf[1] = CILEN_DEFLATE; opt_buf[2] = DEFLATE_MAKE_OPT(DEFLATE_MIN_SIZE); opt_buf[3] = DEFLATE_CHK_SEQUENCE; if (ccp_test(f->unit, opt_buf, CILEN_DEFLATE, 0) <= 0) go->deflate_draft = 0; } if (!go->deflate_correct && !go->deflate_draft) go->deflate = 0; } if (go->predictor_1) { opt_buf[0] = CI_PREDICTOR_1; opt_buf[1] = CILEN_PREDICTOR_1; if (ccp_test(f->unit, opt_buf, CILEN_PREDICTOR_1, 0) <= 0) go->predictor_1 = 0; } if (go->predictor_2) { opt_buf[0] = CI_PREDICTOR_2; opt_buf[1] = CILEN_PREDICTOR_2; if (ccp_test(f->unit, opt_buf, CILEN_PREDICTOR_2, 0) <= 0) go->predictor_2 = 0; } } /* * ccp_cilen - Return total length of our configuration info. */ static int ccp_cilen(f) fsm *f; { ccp_options *go = &ccp_gotoptions[f->unit]; return (go->bsd_compress? CILEN_BSD_COMPRESS: 0) + (go->deflate? CILEN_DEFLATE: 0) + (go->predictor_1? CILEN_PREDICTOR_1: 0) + (go->predictor_2? CILEN_PREDICTOR_2: 0); } /* * ccp_addci - put our requests in a packet. */ static void ccp_addci(f, p, lenp) fsm *f; u_char *p; int *lenp; { int res; ccp_options *go = &ccp_gotoptions[f->unit]; u_char *p0 = p; /* * Add the compression types that we can receive, in decreasing * preference order. Get the kernel to allocate the first one * in case it gets Acked. */ if (go->deflate) { p[0] = go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT; p[1] = CILEN_DEFLATE; p[2] = DEFLATE_MAKE_OPT(go->deflate_size); p[3] = DEFLATE_CHK_SEQUENCE; for (;;) { res = ccp_test(f->unit, p, CILEN_DEFLATE, 0); if (res > 0) { p += CILEN_DEFLATE; break; } if (res < 0 || go->deflate_size <= DEFLATE_MIN_SIZE) { go->deflate = 0; break; } --go->deflate_size; p[2] = DEFLATE_MAKE_OPT(go->deflate_size); } if (p != p0 && go->deflate_correct && go->deflate_draft) { p[0] = CI_DEFLATE_DRAFT; p[1] = CILEN_DEFLATE; p[2] = p[2 - CILEN_DEFLATE]; p[3] = DEFLATE_CHK_SEQUENCE; p += CILEN_DEFLATE; } } if (go->bsd_compress) { p[0] = CI_BSD_COMPRESS; p[1] = CILEN_BSD_COMPRESS; p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits); if (p != p0) { p += CILEN_BSD_COMPRESS; /* not the first option */ } else { for (;;) { res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 0); if (res > 0) { p += CILEN_BSD_COMPRESS; break; } if (res < 0 || go->bsd_bits <= BSD_MIN_BITS) { go->bsd_compress = 0; break; } --go->bsd_bits; p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits); } } } /* XXX Should Predictor 2 be preferable to Predictor 1? */ if (go->predictor_1) { p[0] = CI_PREDICTOR_1; p[1] = CILEN_PREDICTOR_1; if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_1, 0) <= 0) { go->predictor_1 = 0; } else { p += CILEN_PREDICTOR_1; } } if (go->predictor_2) { p[0] = CI_PREDICTOR_2; p[1] = CILEN_PREDICTOR_2; if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_2, 0) <= 0) { go->predictor_2 = 0; } else { p += CILEN_PREDICTOR_2; } } go->method = (p > p0)? p0[0]: -1; *lenp = p - p0; } /* * ccp_ackci - process a received configure-ack, and return * 1 iff the packet was OK. */ static int ccp_ackci(f, p, len) fsm *f; u_char *p; int len; { ccp_options *go = &ccp_gotoptions[f->unit]; u_char *p0 = p; if (go->deflate) { if (len < CILEN_DEFLATE || p[0] != (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT) || p[1] != CILEN_DEFLATE || p[2] != DEFLATE_MAKE_OPT(go->deflate_size) || p[3] != DEFLATE_CHK_SEQUENCE) return 0; p += CILEN_DEFLATE; len -= CILEN_DEFLATE; /* XXX Cope with first/fast ack */ if (len == 0) return 1; if (go->deflate_correct && go->deflate_draft) { if (len < CILEN_DEFLATE || p[0] != CI_DEFLATE_DRAFT || p[1] != CILEN_DEFLATE || p[2] != DEFLATE_MAKE_OPT(go->deflate_size) || p[3] != DEFLATE_CHK_SEQUENCE) return 0; p += CILEN_DEFLATE; len -= CILEN_DEFLATE; } } if (go->bsd_compress) { if (len < CILEN_BSD_COMPRESS || p[0] != CI_BSD_COMPRESS || p[1] != CILEN_BSD_COMPRESS || p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits)) return 0; p += CILEN_BSD_COMPRESS; len -= CILEN_BSD_COMPRESS; /* XXX Cope with first/fast ack */ if (p == p0 && len == 0) return 1; } if (go->predictor_1) { if (len < CILEN_PREDICTOR_1 || p[0] != CI_PREDICTOR_1 || p[1] != CILEN_PREDICTOR_1) return 0; p += CILEN_PREDICTOR_1; len -= CILEN_PREDICTOR_1; /* XXX Cope with first/fast ack */ if (p == p0 && len == 0) return 1; } if (go->predictor_2) { if (len < CILEN_PREDICTOR_2 || p[0] != CI_PREDICTOR_2 || p[1] != CILEN_PREDICTOR_2) return 0; p += CILEN_PREDICTOR_2; len -= CILEN_PREDICTOR_2; /* XXX Cope with first/fast ack */ if (p == p0 && len == 0) return 1; } if (len != 0) return 0; return 1; } /* * ccp_nakci - process received configure-nak. * Returns 1 iff the nak was OK. */ static int ccp_nakci(f, p, len) fsm *f; u_char *p; int len; { ccp_options *go = &ccp_gotoptions[f->unit]; ccp_options no; /* options we've seen already */ ccp_options try; /* options to ask for next time */ memset(&no, 0, sizeof(no)); try = *go; if (go->deflate && len >= CILEN_DEFLATE && p[0] == (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT) && p[1] == CILEN_DEFLATE) { no.deflate = 1; /* * Peer wants us to use a different code size or something. * Stop asking for Deflate if we don't understand his suggestion. */ if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL || DEFLATE_SIZE(p[2]) < DEFLATE_MIN_SIZE || p[3] != DEFLATE_CHK_SEQUENCE) try.deflate = 0; else if (DEFLATE_SIZE(p[2]) < go->deflate_size) try.deflate_size = DEFLATE_SIZE(p[2]); p += CILEN_DEFLATE; len -= CILEN_DEFLATE; if (go->deflate_correct && go->deflate_draft && len >= CILEN_DEFLATE && p[0] == CI_DEFLATE_DRAFT && p[1] == CILEN_DEFLATE) { p += CILEN_DEFLATE; len -= CILEN_DEFLATE; } } if (go->bsd_compress && len >= CILEN_BSD_COMPRESS && p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) { no.bsd_compress = 1; /* * Peer wants us to use a different number of bits * or a different version. */ if (BSD_VERSION(p[2]) != BSD_CURRENT_VERSION) try.bsd_compress = 0; else if (BSD_NBITS(p[2]) < go->bsd_bits) try.bsd_bits = BSD_NBITS(p[2]); p += CILEN_BSD_COMPRESS; len -= CILEN_BSD_COMPRESS; } /* * Predictor-1 and 2 have no options, so they can't be Naked. * * XXX What should we do with any remaining options? */ if (len != 0) return 0; if (f->state != OPENED) *go = try; return 1; } /* * ccp_rejci - reject some of our suggested compression methods. */ static int ccp_rejci(f, p, len) fsm *f; u_char *p; int len; { ccp_options *go = &ccp_gotoptions[f->unit]; ccp_options try; /* options to request next time */ try = *go; /* * Cope with empty configure-rejects by ceasing to send * configure-requests. */ if (len == 0 && all_rejected[f->unit]) return -1; if (go->deflate && len >= CILEN_DEFLATE && p[0] == (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT) && p[1] == CILEN_DEFLATE) { if (p[2] != DEFLATE_MAKE_OPT(go->deflate_size) || p[3] != DEFLATE_CHK_SEQUENCE) return 0; /* Rej is bad */ if (go->deflate_correct) try.deflate_correct = 0; else try.deflate_draft = 0; p += CILEN_DEFLATE; len -= CILEN_DEFLATE; if (go->deflate_correct && go->deflate_draft && len >= CILEN_DEFLATE && p[0] == CI_DEFLATE_DRAFT && p[1] == CILEN_DEFLATE) { if (p[2] != DEFLATE_MAKE_OPT(go->deflate_size) || p[3] != DEFLATE_CHK_SEQUENCE) return 0; /* Rej is bad */ try.deflate_draft = 0; p += CILEN_DEFLATE; len -= CILEN_DEFLATE; } if (!try.deflate_correct && !try.deflate_draft) try.deflate = 0; } if (go->bsd_compress && len >= CILEN_BSD_COMPRESS && p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) { if (p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits)) return 0; try.bsd_compress = 0; p += CILEN_BSD_COMPRESS; len -= CILEN_BSD_COMPRESS; } if (go->predictor_1 && len >= CILEN_PREDICTOR_1 && p[0] == CI_PREDICTOR_1 && p[1] == CILEN_PREDICTOR_1) { try.predictor_1 = 0; p += CILEN_PREDICTOR_1; len -= CILEN_PREDICTOR_1; } if (go->predictor_2 && len >= CILEN_PREDICTOR_2 && p[0] == CI_PREDICTOR_2 && p[1] == CILEN_PREDICTOR_2) { try.predictor_2 = 0; p += CILEN_PREDICTOR_2; len -= CILEN_PREDICTOR_2; } if (len != 0) return 0; if (f->state != OPENED) *go = try; return 1; } /* * ccp_reqci - processed a received configure-request. * Returns CONFACK, CONFNAK or CONFREJ and the packet modified * appropriately. */ static int ccp_reqci(f, p, lenp, dont_nak) fsm *f; u_char *p; int *lenp; int dont_nak; { int ret, newret, res; u_char *p0, *retp; int len, clen, type, nb; ccp_options *ho = &ccp_hisoptions[f->unit]; ccp_options *ao = &ccp_allowoptions[f->unit]; ret = CONFACK; retp = p0 = p; len = *lenp; memset(ho, 0, sizeof(ccp_options)); ho->method = (len > 0)? p[0]: -1; while (len > 0) { newret = CONFACK; if (len < 2 || p[1] < 2 || p[1] > len) { /* length is bad */ clen = len; newret = CONFREJ; } else { type = p[0]; clen = p[1]; switch (type) { case CI_DEFLATE: case CI_DEFLATE_DRAFT: if (!ao->deflate || clen != CILEN_DEFLATE || (!ao->deflate_correct && type == CI_DEFLATE) || (!ao->deflate_draft && type == CI_DEFLATE_DRAFT)) { newret = CONFREJ; break; } ho->deflate = 1; ho->deflate_size = nb = DEFLATE_SIZE(p[2]); if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL || p[3] != DEFLATE_CHK_SEQUENCE || nb > ao->deflate_size || nb < DEFLATE_MIN_SIZE) { newret = CONFNAK; if (!dont_nak) { p[2] = DEFLATE_MAKE_OPT(ao->deflate_size); p[3] = DEFLATE_CHK_SEQUENCE; /* fall through to test this #bits below */ } else break; } /* * Check whether we can do Deflate with the window * size they want. If the window is too big, reduce * it until the kernel can cope and nak with that. * We only check this for the first option. */ if (p == p0) { for (;;) { res = ccp_test(f->unit, p, CILEN_DEFLATE, 1); if (res > 0) break; /* it's OK now */ if (res < 0 || nb == DEFLATE_MIN_SIZE || dont_nak) { newret = CONFREJ; p[2] = DEFLATE_MAKE_OPT(ho->deflate_size); break; } newret = CONFNAK; --nb; p[2] = DEFLATE_MAKE_OPT(nb); } } break; case CI_BSD_COMPRESS: if (!ao->bsd_compress || clen != CILEN_BSD_COMPRESS) { newret = CONFREJ; break; } ho->bsd_compress = 1; ho->bsd_bits = nb = BSD_NBITS(p[2]); if (BSD_VERSION(p[2]) != BSD_CURRENT_VERSION || nb > ao->bsd_bits || nb < BSD_MIN_BITS) { newret = CONFNAK; if (!dont_nak) { p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, ao->bsd_bits); /* fall through to test this #bits below */ } else break; } /* * Check whether we can do BSD-Compress with the code * size they want. If the code size is too big, reduce * it until the kernel can cope and nak with that. * We only check this for the first option. */ if (p == p0) { for (;;) { res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 1); if (res > 0) break; if (res < 0 || nb == BSD_MIN_BITS || dont_nak) { newret = CONFREJ; p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, ho->bsd_bits); break; } newret = CONFNAK; --nb; p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb); } } break; case CI_PREDICTOR_1: if (!ao->predictor_1 || clen != CILEN_PREDICTOR_1) { newret = CONFREJ; break; } ho->predictor_1 = 1; if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_1, 1) <= 0) { newret = CONFREJ; } break; case CI_PREDICTOR_2: if (!ao->predictor_2 || clen != CILEN_PREDICTOR_2) { newret = CONFREJ; break; } ho->predictor_2 = 1; if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_2, 1) <= 0) { newret = CONFREJ; } break; default: newret = CONFREJ; } } if (newret == CONFNAK && dont_nak) newret = CONFREJ; if (!(newret == CONFACK || (newret == CONFNAK && ret == CONFREJ))) { /* we're returning this option */ if (newret == CONFREJ && ret == CONFNAK) retp = p0; ret = newret; if (p != retp) BCOPY(p, retp, clen); retp += clen; } p += clen; len -= clen; } if (ret != CONFACK) { if (ret == CONFREJ && *lenp == retp - p0) all_rejected[f->unit] = 1; else *lenp = retp - p0; } return ret; } /* * Make a string name for a compression method (or 2). */ static char * method_name(opt, opt2) ccp_options *opt, *opt2; { static char result[64]; if (!ANY_COMPRESS(*opt)) return "(none)"; switch (opt->method) { case CI_DEFLATE: case CI_DEFLATE_DRAFT: if (opt2 != NULL && opt2->deflate_size != opt->deflate_size) snprintf(result, sizeof result, "Deflate%s (%d/%d)", (opt->method == CI_DEFLATE_DRAFT? "(old#)": ""), opt->deflate_size, opt2->deflate_size); else snprintf(result, sizeof result, "Deflate%s (%d)", (opt->method == CI_DEFLATE_DRAFT? "(old#)": ""), opt->deflate_size); break; case CI_BSD_COMPRESS: if (opt2 != NULL && opt2->bsd_bits != opt->bsd_bits) snprintf(result, sizeof result, "BSD-Compress (%d/%d)", opt->bsd_bits, opt2->bsd_bits); else snprintf(result, sizeof result, "BSD-Compress (%d)", opt->bsd_bits); break; case CI_PREDICTOR_1: return "Predictor 1"; case CI_PREDICTOR_2: return "Predictor 2"; default: snprintf(result, sizeof result, "Method %d", opt->method); } return result; } /* * CCP has come up - inform the kernel driver and log a message. */ static void ccp_up(f) fsm *f; { ccp_options *go = &ccp_gotoptions[f->unit]; ccp_options *ho = &ccp_hisoptions[f->unit]; char method1[64]; ccp_flags_set(f->unit, 1, 1); if (ANY_COMPRESS(*go)) { if (ANY_COMPRESS(*ho)) { if (go->method == ho->method) { syslog(LOG_NOTICE, "%s compression enabled", method_name(go, ho)); } else { strncpy(method1, method_name(go, NULL), sizeof method1); syslog(LOG_NOTICE, "%s / %s compression enabled", method1, method_name(ho, NULL)); } } else syslog(LOG_NOTICE, "%s receive compression enabled", method_name(go, NULL)); } else if (ANY_COMPRESS(*ho)) syslog(LOG_NOTICE, "%s transmit compression enabled", method_name(ho, NULL)); } /* * CCP has gone down - inform the kernel driver. */ static void ccp_down(f) fsm *f; { if (ccp_localstate[f->unit] & RACK_PENDING) UNTIMEOUT(ccp_rack_timeout, f); ccp_localstate[f->unit] = 0; ccp_flags_set(f->unit, 1, 0); } /* * Print the contents of a CCP packet. */ static char *ccp_codenames[] = { "ConfReq", "ConfAck", "ConfNak", "ConfRej", "TermReq", "TermAck", "CodeRej", NULL, NULL, NULL, NULL, NULL, NULL, "ResetReq", "ResetAck", }; static int ccp_printpkt(p, plen, printer, arg) u_char *p; int plen; void (*printer)(void *, char *, ...); void *arg; { u_char *p0, *optend; int code, id, len; int optlen; p0 = p; if (plen < HEADERLEN) return 0; code = p[0]; id = p[1]; len = (p[2] << 8) + p[3]; if (len < HEADERLEN || len > plen) return 0; if (code >= 1 && code <= sizeof(ccp_codenames) / sizeof(char *) && ccp_codenames[code-1] != NULL) printer(arg, " %s", ccp_codenames[code-1]); else printer(arg, " code=0x%x", code); printer(arg, " id=0x%x", id); len -= HEADERLEN; p += HEADERLEN; switch (code) { case CONFREQ: case CONFACK: case CONFNAK: case CONFREJ: /* print list of possible compression methods */ while (len >= 2) { code = p[0]; optlen = p[1]; if (optlen < 2 || optlen > len) break; printer(arg, " <"); len -= optlen; optend = p + optlen; switch (code) { case CI_DEFLATE: case CI_DEFLATE_DRAFT: if (optlen >= CILEN_DEFLATE) { printer(arg, "deflate%s %d", (code == CI_DEFLATE_DRAFT? "(old#)": ""), DEFLATE_SIZE(p[2])); if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL) printer(arg, " method %d", DEFLATE_METHOD(p[2])); if (p[3] != DEFLATE_CHK_SEQUENCE) printer(arg, " check %d", p[3]); p += CILEN_DEFLATE; } break; case CI_BSD_COMPRESS: if (optlen >= CILEN_BSD_COMPRESS) { printer(arg, "bsd v%d %d", BSD_VERSION(p[2]), BSD_NBITS(p[2])); p += CILEN_BSD_COMPRESS; } break; case CI_PREDICTOR_1: if (optlen >= CILEN_PREDICTOR_1) { printer(arg, "predictor 1"); p += CILEN_PREDICTOR_1; } break; case CI_PREDICTOR_2: if (optlen >= CILEN_PREDICTOR_2) { printer(arg, "predictor 2"); p += CILEN_PREDICTOR_2; } break; } while (p < optend) printer(arg, " %.2x", *p++); printer(arg, ">"); } break; case TERMACK: case TERMREQ: if (len > 0 && *p >= ' ' && *p < 0x7f) { print_string(p, len, printer, arg); p += len; len = 0; } break; } /* dump out the rest of the packet in hex */ while (--len >= 0) printer(arg, " %.2x", *p++); return p - p0; } /* * We have received a packet that the decompressor failed to * decompress. Here we would expect to issue a reset-request, but * Motorola has a patent on resetting the compressor as a result of * detecting an error in the decompressed data after decompression. * (See US patent 5,130,993; international patent publication number * WO 91/10289; Australian patent 73296/91.) * * So we ask the kernel whether the error was detected after * decompression; if it was, we take CCP down, thus disabling * compression :-(, otherwise we issue the reset-request. */ static void ccp_datainput(unit, pkt, len) int unit; u_char *pkt; int len; { fsm *f; f = &ccp_fsm[unit]; if (f->state == OPENED) { if (ccp_fatal_error(unit)) { /* * Disable compression by taking CCP down. */ syslog(LOG_ERR, "Lost compression sync: disabling compression"); ccp_close(unit, "Lost compression sync"); } else { /* * Send a reset-request to reset the peer's compressor. * We don't do that if we are still waiting for an * acknowledgement to a previous reset-request. */ if (!(ccp_localstate[f->unit] & RACK_PENDING)) { fsm_sdata(f, CCP_RESETREQ, f->reqid = ++f->id, NULL, 0); TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT); ccp_localstate[f->unit] |= RACK_PENDING; } else ccp_localstate[f->unit] |= RREQ_REPEAT; } } } /* * Timeout waiting for reset-ack. */ static void ccp_rack_timeout(arg) void *arg; { fsm *f = arg; if (f->state == OPENED && ccp_localstate[f->unit] & RREQ_REPEAT) { fsm_sdata(f, CCP_RESETREQ, f->reqid, NULL, 0); TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT); ccp_localstate[f->unit] &= ~RREQ_REPEAT; } else ccp_localstate[f->unit] &= ~RACK_PENDING; }