pfkey_v2_parser.c

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			octx = &((struct sha1_ctx*)(tdbp->tdb_key_a))->octx;
			SHA1Init(octx);
			SHA1Update(octx, kb, AHSHA196_BLKLEN);
			
#  if 0 /* we don't really want to print these unless there are really big problems */
			KLIPS_PRINT(debug_pfkey && sysctl_ipsec_debug_verbose,
				    "klips_debug:pfkey_tdb_init: "
				    "SHA1 ictx=0x%08x %08x %08x %08x octx=0x%08x %08x %08x %08x\n",
				    ((__u32*)ictx)[0],
				    ((__u32*)ictx)[1],
				    ((__u32*)ictx)[2],
				    ((__u32*)ictx)[3],
				    ((__u32*)octx)[0],
				    ((__u32*)octx)[1],
				    ((__u32*)octx)[2],
				    ((__u32*)octx)[3] );
#  endif
			memset(akp, 0, aks);
			kfree(akp);
			break;
		}
# endif /* CONFIG_IPSEC_AUTH_HMAC_SHA1 */
		case AH_NONE:
			break;
		default:
			KLIPS_PRINT(debug_pfkey,
				    "klips_debug:pfkey_tdb_init: "
				    "authalg=%d support not available in the kernel.\n",
				    tdbp->tdb_authalg);
			SENDERR(EINVAL);
		}
	}
			break;
#endif /* !CONFIG_IPSEC_ESP */
#ifdef CONFIG_IPSEC_IPCOMP
	case IPPROTO_COMP:
		tdbp->tdb_comp_adapt_tries = 0;
		tdbp->tdb_comp_adapt_skip = 0;
		tdbp->tdb_comp_ratio_cbytes = 0;
		tdbp->tdb_comp_ratio_dbytes = 0;
		break;
#endif /* CONFIG_IPSEC_IPCOMP */
	default:
		KLIPS_PRINT(debug_pfkey,
			    "klips_debug:pfkey_tdb_init: "
			    "proto=%d unknown.\n",
			    tdbp->tdb_said.proto);
		SENDERR(EINVAL);
	}
	
 errlab:
	return(error);
}


int
pfkey_safe_build(int error, struct sadb_ext *extensions[SADB_MAX+1])
{
	KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_safe_build: "
		    "error=%d\n",
		    error);
	if (!error) {
		KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_safe_build:"
			    "success.\n");
		return 1;
	} else {
		KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_safe_build:"
			    "caught error %d\n",
			    error);
		pfkey_extensions_free(extensions);
		return 0;
	}
}


DEBUG_NO_STATIC int
pfkey_getspi_parse(struct sock *sk, struct sadb_ext **extensions, struct pfkey_extracted_data* extr)
{
	int error = 0;
	ipsec_spi_t minspi = htonl(256), maxspi = htonl(-1L);
	int found_avail = 0;
	struct tdb *tdbq;
	char sa[SATOA_BUF];
	size_t sa_len;
	struct sadb_ext *extensions_reply[SADB_EXT_MAX+1];
	struct sadb_msg *pfkey_reply = NULL;
	struct socket_list *pfkey_socketsp;
	uint8_t satype = ((struct sadb_msg*)extensions[SADB_EXT_RESERVED])->sadb_msg_satype;

	KLIPS_PRINT(debug_pfkey,
		    "klips_debug:pfkey_getspi_parse: .\n");

	pfkey_extensions_init(extensions_reply);

	if(!extr || !extr->tdb) {
		KLIPS_PRINT(debug_pfkey,
			    "klips_debug:pfkey_getspi_parse: "
			    "error, extr or extr->tdb pointer NULL\n");
		SENDERR(EINVAL);
	}

	if(extensions[SADB_EXT_SPIRANGE]) {
		minspi = ((struct sadb_spirange *)extensions[SADB_EXT_SPIRANGE])->sadb_spirange_min;
		maxspi = ((struct sadb_spirange *)extensions[SADB_EXT_SPIRANGE])->sadb_spirange_max;
	}

	if(maxspi == minspi) {
		extr->tdb->tdb_said.spi = maxspi;
		if((tdbq = gettdb(&(extr->tdb->tdb_said)))) {
			sa_len = satoa(extr->tdb->tdb_said, 0, sa, SATOA_BUF);
			KLIPS_PRINT(debug_pfkey,
				    "klips_debug:pfkey_getspi_parse: "
				    "EMT_GETSPI found an old Tunnel Descriptor Block for SA: %s, delete it first.\n",
				    sa_len ? sa : " (error)");
			SENDERR(EEXIST);
		} else {
			found_avail = 1;
		}
	} else {
		int i = 0;
		__u32 rand_val;
		__u32 spi_diff;
		while( ( i < (spi_diff = (ntohl(maxspi) - ntohl(minspi)))) && !found_avail ) {
			get_random_bytes((void*) &(rand_val),
					 /* sizeof(extr->tdb->tdb_said.spi) */
					 ( (spi_diff < (2^8))  ? 1 :
					   ( (spi_diff < (2^16)) ? 2 :
					     ( (spi_diff < (2^24)) ? 3 :
					   4 ) ) ) );
			extr->tdb->tdb_said.spi = htonl(ntohl(minspi) +
					      (rand_val %
					      (spi_diff + 1)));
			i++;
			tdbq = gettdb(&(extr->tdb->tdb_said));
			if(!tdbq) {
				found_avail = 1;
			}
		}
	}

	sa_len = satoa(extr->tdb->tdb_said, 0, sa, SATOA_BUF);

	if (!found_avail) {
		KLIPS_PRINT(debug_pfkey,
			    "klips_debug:pfkey_getspi_parse: "
			    "found an old Tunnel Descriptor Block for SA: %s, delete it first.\n",
			    sa_len ? sa : " (error)");
		SENDERR(EEXIST);
	}

	if(ip_chk_addr((unsigned long)extr->tdb->tdb_said.dst.s_addr) == IS_MYADDR) {
		extr->tdb->tdb_flags |= EMT_INBOUND;
	}

	KLIPS_PRINT(debug_pfkey,
		    "klips_debug:pfkey_getspi_parse: "
		    "existing Tunnel Descriptor Block not found (this is good) for SA: %s, %s-bound, allocating.\n",
		    sa_len ? sa : " (error)",
		    extr->tdb->tdb_flags & EMT_INBOUND ? "in" : "out");
	
	/* XXX extr->tdb->tdb_rcvif = &(enc_softc[em->em_if].enc_if);*/
	extr->tdb->tdb_rcvif = NULL;
	extr->tdb->tdb_lifetime_addtime_c = jiffies/HZ;

	extr->tdb->tdb_state = SADB_SASTATE_LARVAL;

	if(!extr->tdb->tdb_lifetime_allocations_c) {
		extr->tdb->tdb_lifetime_allocations_c += 1;
	}

	if(!(pfkey_safe_build(error = pfkey_msg_hdr_build(&extensions_reply[0],
							  SADB_GETSPI,
							  satype,
							  0,
							  ((struct sadb_msg*)extensions[SADB_EXT_RESERVED])->sadb_msg_seq,
							  ((struct sadb_msg*)extensions[SADB_EXT_RESERVED])->sadb_msg_pid),
			      extensions_reply)
	     && pfkey_safe_build(error = pfkey_sa_build(&extensions_reply[SADB_EXT_SA],
						SADB_EXT_SA,
						extr->tdb->tdb_said.spi,
						0,
						SADB_SASTATE_LARVAL,
						0,
						0,
						0),
				 extensions_reply)
	     && pfkey_safe_build(error = pfkey_address_build(&extensions_reply[SADB_EXT_ADDRESS_SRC],
						     SADB_EXT_ADDRESS_SRC,
						     0, /*extr->tdb->tdb_said.proto,*/
						     0,
						     extr->tdb->tdb_addr_s),
				 extensions_reply)
	     && pfkey_safe_build(error = pfkey_address_build(&extensions_reply[SADB_EXT_ADDRESS_DST],
						     SADB_EXT_ADDRESS_DST,
						     0, /*extr->tdb->tdb_said.proto,*/
						     0,
						     extr->tdb->tdb_addr_d),
				 extensions_reply) )) {
		KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_getspi_parse: "
			    "failed to build the getspi reply message extensions\n");
		goto errlab;
	}
	
	if((error = puttdb(extr->tdb))) {
		KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_getspi_parse: "
			    "failed to add the larval SA with error=%d.\n",
			    error);
		SENDERR(-error);
	}
	extr->tdb = NULL;
	
	KLIPS_PRINT(debug_pfkey,
		    "klips_debug:pfkey_getspi_parse: "
		    "successful for SA: %s\n",
		    sa_len ? sa : " (error)");
	
	if((error = pfkey_msg_build(&pfkey_reply, extensions_reply, EXT_BITS_OUT))) {
		KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_getspi_parse: "
			    "failed to build the getspi reply message\n");
		SENDERR(-error);
	}
	for(pfkey_socketsp = pfkey_open_sockets;
	    pfkey_socketsp;
	    pfkey_socketsp = pfkey_socketsp->next) {
		if((error = pfkey_upmsg(pfkey_socketsp->socketp, pfkey_reply))) {
			KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_getspi_parse: "
				    "sending up getspi reply message for satype=%d(%s) to socket=%p failed with error=%d.\n",
				    satype,
				    satype2name(satype),
				    pfkey_socketsp->socketp,
				    error);
			SENDERR(-error);
		}
		KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_getspi_parse: "
			    "sending up getspi reply message for satype=%d(%s) to socket=%p succeeded.\n",
			    satype,
			    satype2name(satype),
			    pfkey_socketsp->socketp);
	}

 errlab:
	if (pfkey_reply) {
		pfkey_msg_free(&pfkey_reply);
	}
	pfkey_extensions_free(extensions_reply);
	return error;
}

DEBUG_NO_STATIC int
pfkey_update_parse(struct sock *sk, struct sadb_ext **extensions, struct pfkey_extracted_data* extr)
{
	int error = 0;
	struct tdb* tdbq;
	char sa[SATOA_BUF];
	size_t sa_len;
	struct sadb_ext *extensions_reply[SADB_EXT_MAX+1];
	struct sadb_msg *pfkey_reply = NULL;
	struct socket_list *pfkey_socketsp;
	uint8_t satype = ((struct sadb_msg*)extensions[SADB_EXT_RESERVED])->sadb_msg_satype;

	KLIPS_PRINT(debug_pfkey,
		    "klips_debug:pfkey_update_parse: .\n");

	pfkey_extensions_init(extensions_reply);

	if(((struct sadb_sa*)extensions[SADB_EXT_SA])->sadb_sa_state != SADB_SASTATE_MATURE) {
		KLIPS_PRINT(debug_pfkey,
			    "klips_debug:pfkey_update_parse: "
			    "error, sa_state=%d must be MATURE=%d\n",
			    ((struct sadb_sa*)extensions[SADB_EXT_SA])->sadb_sa_state,
			    SADB_SASTATE_MATURE);
		SENDERR(EINVAL);
	}

	if(!extr || !extr->tdb) {
		KLIPS_PRINT(debug_pfkey,
			    "klips_debug:pfkey_update_parse: "
			    "error, extr or extr->tdb pointer NULL\n");
		SENDERR(EINVAL);
	}

	sa_len = satoa(extr->tdb->tdb_said, 0, sa, SATOA_BUF);

	spin_lock_bh(&tdb_lock);

	tdbq = gettdb(&(extr->tdb->tdb_said));
	if (!tdbq) {
		spin_unlock_bh(&tdb_lock);
		KLIPS_PRINT(debug_pfkey,
			    "klips_debug:pfkey_update_parse: "
			    "reserved Tunnel Descriptor Block for SA: %s not found.  Call SADB_GETSPI first or call SADB_ADD instead.\n",
			    sa_len ? sa : " (error)");
		SENDERR(EEXIST);
	}

	if(ip_chk_addr((unsigned long)extr->tdb->tdb_said.dst.s_addr) == IS_MYADDR) {
		extr->tdb->tdb_flags |= EMT_INBOUND;
	}

	KLIPS_PRINT(debug_pfkey,
		    "klips_debug:pfkey_update_parse: "
		    "existing Tunnel Descriptor Block found (this is good) for SA: %s, %s-bound, updating.\n",
		    sa_len ? sa : " (error)",
		    extr->tdb->tdb_flags & EMT_INBOUND ? "in" : "out");
	
	/* XXX extr->tdb->tdb_rcvif = &(enc_softc[em->em_if].enc_if);*/
	extr->tdb->tdb_rcvif = NULL;
	if ((error = pfkey_tdb_init(extr->tdb, extensions))) {
		spin_unlock_bh(&tdb_lock);
		KLIPS_PRINT(debug_pfkey,
			    "klips_debug:pfkey_update_parse: "
			    "not successful for SA: %s, deleting.\n",
			    sa_len ? sa : " (error)");
		SENDERR(-error);
	}

	extr->tdb->tdb_lifetime_addtime_c = tdbq->tdb_lifetime_addtime_c;
	if((error = deltdbchain(tdbq))) {
		spin_unlock_bh(&tdb_lock);
		KLIPS_PRINT(debug_pfkey,
			    "klips_debug:pfkey_update_parse: "
			    "error=%d, trouble deleting intermediate tdb for SA=%s.\n",
			    error,
			    sa_len ? sa : " (error)");
		SENDERR(-error);
	}

	spin_unlock_bh(&tdb_lock);
	
	if(!(pfkey_safe_build(error = pfkey_msg_hdr_build(&extensions_reply[0],
							  SADB_UPDATE,
							  satype,
							  0,
							  ((struct sadb_msg*)extensions[SADB_EXT_RESERVED])->sadb_msg_seq,
							  ((struct sadb_msg*)extensions[SADB_EXT_RESERVED])->sadb_msg_pid),
			      extensions_reply)
	     && pfkey_safe_build(error = pfkey_sa_build(&extensions_reply[SADB_EXT_SA],
							SADB_EXT_SA,
							extr->tdb->tdb_said.spi,
							extr->tdb->tdb_replaywin,
							extr->tdb->tdb_state,
							extr->tdb->tdb_authalg,
							extr->tdb->tdb_encalg,
							extr->tdb->tdb_flags),
				 extensions_reply)
	     /* The 3 lifetime extentions should only be sent if non-zero. */
	     && (extensions[SADB_EXT_LIFETIME_HARD]
		 ? pfkey_safe_build(error = pfkey_lifetime_build(&extensions_reply[SADB_EXT_LIFETIME_HARD],
								 SADB_EXT_LIFETIME_HARD,
								 extr->tdb->tdb_lifetime_allocations_h,
								 extr->tdb->tdb_lifetime_bytes_h,
								 extr->tdb->tdb_lifetime_addtime_h,
								 extr->tdb->tdb_lifetime_usetime_h),
				    extensions_reply) : 1)
	     && (extensions[SADB_EXT_LIFETIME_SOFT]
		 ? pfkey_safe_build(error = pfkey_lifetime_build(&extensions_reply[SADB_EXT_LIFETIME_SOFT],
								 SADB_EXT_LIFETIME_SOFT,
								 extr->tdb->tdb_lifetime_allocations_c,
								 extr->tdb->tdb_lifetime_bytes_c,
								 extr->tdb->tdb_lifetime_addtime_c,
								 extr->tdb->tdb_lifetime_usetime_c),
				    extensions_reply) : 1)
	     && (extr->tdb->tdb_lifetime_allocations_c
		 || extr->tdb->tdb_lifetime_bytes_c
		 || extr->tdb->tdb_lifetime_addtime_c
		 || extr->tdb->tdb_lifetime_usetime_c
		 ? pfkey_safe_build(error = pfkey_lifetime_build(&extensions_reply[SADB_EXT_LIFETIME_CURRENT],
								 SADB_EXT_LIFETIME_CURRENT,
								 extr->tdb->tdb_lifetime_allocations_c,
								 extr->tdb->tdb_lifetime_bytes_c,
								 extr->tdb->tdb_lifetime_addtime_c,
								 extr->tdb->tdb_lifetime_usetime_c),
				    extensions_reply) : 1)
	     && pfkey_safe_build(error = pfkey_address_build(&extensions_reply[SADB_EXT_ADDRESS_SRC],
							     SADB_EXT_ADDRESS_SRC,
							     0, /*extr->tdb->tdb_said.proto,*/
							     0,
							     extr->tdb->tdb_addr_s),
				 extensions_reply)
	     && pfkey_safe_build(error = pfkey_address_build(&extensions_reply[SADB_EXT_ADDRESS_DST],
							     SADB_EXT_ADDRESS_DST,
							     0, /*extr->tdb->tdb_said.proto,*/
							     0,
							     extr->tdb->tdb_addr_d),
				 extensions_reply)
#if 0
	     /* FIXME: This won't work yet because I have not finished
		it. */
	     && (extr->tdb->tdb_ident_data_s
		 ? pfkey_safe_build(error = pfkey_ident_build(&extensions_reply[SADB_EXT_IDENTITY_SRC],
							      SADB_EXT_IDENTITY_SRC,
							      SADB_IDENTTYPE_PREFIX,
							      0,
							      extr->tdb->tdb_ident_data_s),
				    extensions_reply) : 1)
	     /* FIXME: This won't work yet because I have not finished
		it. */
	     && (extr->tdb->tdb_ident_data_d
		 ? pfkey_safe_build(error = pfkey_ident_build(&extensions_reply[SADB_EXT_IDENTITY_DST],
							      SADB_EXT_IDENTITY_DST,
							      SADB_IDENTTYPE_PREFIX,
							      0,
							      extr->tdb->tdb_ident_data_d),
				    extensions_reply) : 1)
	     /* FIXME: This won't work yet because I have not finished
		it. */
	     && (extr->tdb->tdb_sens_
		 ? pfkey_safe_build(error = pfkey_sens_build(&extensions_reply[SADB_EXT_SENSITIVITY],
							     extr->tdb->tdb_sens_dpd,
							     extr->tdb->tdb_sens_sens_level,
							     extr->tdb->tdb_sens_sens_len,
							     extr->tdb->tdb_sens_sens_bitmap,
							     extr->tdb->tdb_sens_integ_level,
							     extr->tdb->tdb_sens_integ_len,
							     extr->tdb->tdb_sens_integ_bitmap),
				    extensions_reply) : 1)
#endif
		)) {
		KLIPS_PRINT(debug_pfkey, "klips_debug:pfkey_update_parse: "