X-Git-Url: https://git.tcpdump.org/libpcap/blobdiff_plain/0f740c78ff4523165a177d3258da8e8872096301..fda83a89fd2600d23f669f8c48bea820a988008c:/gencode.c diff --git a/gencode.c b/gencode.c index 6f03326c..090a8ed3 100644 --- a/gencode.c +++ b/gencode.c @@ -103,6 +103,10 @@ #define ETHERMTU 1500 +#ifndef ETHERTYPE_TEB +#define ETHERTYPE_TEB 0x6558 +#endif + #ifndef IPPROTO_HOPOPTS #define IPPROTO_HOPOPTS 0 #endif @@ -119,6 +123,8 @@ #define IPPROTO_SCTP 132 #endif +#define GENEVE_PORT 6081 + #ifdef HAVE_OS_PROTO_H #include "os-proto.h" #endif @@ -195,6 +201,7 @@ enum e_offrel { OR_PREVLINKHDR, /* previous link-layer header */ OR_LLC, /* 802.2 LLC header */ OR_PREVMPLSHDR, /* previous MPLS header */ + OR_LINKTYPE, /* link-layer type */ OR_LINKPL, /* link-layer payload */ OR_LINKPL_NOSNAP, /* link-layer payload, with no SNAP header at the link layer */ OR_TRAN_IPV4, /* transport-layer header, with IPv4 network layer */ @@ -308,6 +315,7 @@ static struct slist *xfer_to_a(struct arth *); static struct block *gen_mac_multicast(int); static struct block *gen_len(int, int); static struct block *gen_check_802_11_data_frame(void); +static struct block *gen_geneve_ll_check(void); static struct block *gen_ppi_dlt_check(void); static struct block *gen_msg_abbrev(int type); @@ -825,6 +833,7 @@ static bpf_abs_offset off_outermostlinkhdr; off_linkhdr.is_variable = new_is_variable; \ off_linkhdr.constant_part = new_constant_part; \ off_linkhdr.reg = new_reg; \ + is_geneve = 0; \ } /* @@ -834,10 +843,8 @@ static bpf_abs_offset off_linkpl; /* * "off_linktype" is the offset to information in the link-layer header - * giving the packet type. This offset is relative to the beginning - * of the link-layer header - i.e., it doesn't include off_linkhdr.constant_part - so - * loads with an offset that includes "off_linktype" should use - * OR_LINKHDR. + * giving the packet type. This is an absolute offset from the beginning + * of the packet. * * For Ethernet, it's the offset of the Ethernet type field; this * means that it must have a value that skips VLAN tags. @@ -854,15 +861,23 @@ static bpf_abs_offset off_linkpl; * * For Linux cooked sockets, it's the offset of the type field. * - * It's set to -1 for no encapsulation, in which case, IP is assumed. + * off_linktype.constant_part is set to -1 for no encapsulation, + * in which case, IP is assumed. */ -static u_int off_linktype; +static bpf_abs_offset off_linktype; /* * TRUE if the link layer includes an ATM pseudo-header. */ static int is_atm = 0; +/* + * TRUE if "geneve" appeared in the filter; it causes us to generate + * code that checks for a Geneve header and assume that later filters + * apply to the encapsulated payload. + */ +static int is_geneve = 0; + /* * These are offsets for the ATM pseudo-header. */ @@ -952,6 +967,10 @@ init_linktype(p) off_linkpl.is_variable = 0; off_linkpl.reg = -1; + off_linktype.constant_part = 0; + off_linktype.is_variable = 0; + off_linktype.reg = -1; + /* * Assume it's not raw ATM with a pseudo-header, for now. */ @@ -961,6 +980,11 @@ init_linktype(p) off_proto = -1; off_payload = -1; + /* + * And not Geneve. + */ + is_geneve = 0; + /* * And assume we're not doing SS7. */ @@ -977,21 +1001,21 @@ init_linktype(p) switch (linktype) { case DLT_ARCNET: - off_linktype = 2; + off_linktype.constant_part = 2; off_linkpl.constant_part = 6; off_nl = 0; /* XXX in reality, variable! */ off_nl_nosnap = 0; /* no 802.2 LLC */ break; case DLT_ARCNET_LINUX: - off_linktype = 4; + off_linktype.constant_part = 4; off_linkpl.constant_part = 8; off_nl = 0; /* XXX in reality, variable! */ off_nl_nosnap = 0; /* no 802.2 LLC */ break; case DLT_EN10MB: - off_linktype = 12; + off_linktype.constant_part = 12; off_linkpl.constant_part = 14; /* Ethernet header length */ off_nl = 0; /* Ethernet II */ off_nl_nosnap = 3; /* 802.3+802.2 */ @@ -1002,7 +1026,7 @@ init_linktype(p) * SLIP doesn't have a link level type. The 16 byte * header is hacked into our SLIP driver. */ - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = 16; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ @@ -1010,7 +1034,7 @@ init_linktype(p) case DLT_SLIP_BSDOS: /* XXX this may be the same as the DLT_PPP_BSDOS case */ - off_linktype = -1; + off_linktype.constant_part = -1; /* XXX end */ off_linkpl.constant_part = 24; off_nl = 0; @@ -1019,14 +1043,14 @@ init_linktype(p) case DLT_NULL: case DLT_LOOP: - off_linktype = 0; + off_linktype.constant_part = 0; off_linkpl.constant_part = 4; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ break; case DLT_ENC: - off_linktype = 0; + off_linktype.constant_part = 0; off_linkpl.constant_part = 12; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ @@ -1036,7 +1060,7 @@ init_linktype(p) case DLT_PPP_PPPD: case DLT_C_HDLC: /* BSD/OS Cisco HDLC */ case DLT_PPP_SERIAL: /* NetBSD sync/async serial PPP */ - off_linktype = 2; /* skip HDLC-like framing */ + off_linktype.constant_part = 2; /* skip HDLC-like framing */ off_linkpl.constant_part = 4; /* skip HDLC-like framing and protocol field */ off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ @@ -1047,14 +1071,14 @@ init_linktype(p) * This does no include the Ethernet header, and * only covers session state. */ - off_linktype = 6; + off_linktype.constant_part = 6; off_linkpl.constant_part = 8; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ break; case DLT_PPP_BSDOS: - off_linktype = 5; + off_linktype.constant_part = 5; off_linkpl.constant_part = 24; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ @@ -1069,8 +1093,8 @@ init_linktype(p) * is being used and pick out the encapsulated Ethernet type. * XXX - should we generate code to check for SNAP? */ - off_linktype = 13; - off_linktype += pcap_fddipad; + off_linktype.constant_part = 13; + off_linktype.constant_part += pcap_fddipad; off_linkpl.constant_part = 13; /* FDDI MAC header length */ off_linkpl.constant_part += pcap_fddipad; off_nl = 8; /* 802.2+SNAP */ @@ -1101,7 +1125,7 @@ init_linktype(p) * the 16-bit value at an offset of 14 (shifted right * 8 - figure out which byte that is). */ - off_linktype = 14; + off_linktype.constant_part = 14; off_linkpl.constant_part = 14; /* Token Ring MAC header length */ off_nl = 8; /* 802.2+SNAP */ off_nl_nosnap = 3; /* 802.2 */ @@ -1117,7 +1141,8 @@ init_linktype(p) case DLT_IEEE802_11: /* * 802.11 doesn't really have a link-level type field. - * We set "off_linktype" to the offset of the LLC header. + * We set "off_linktype.constant_part" to the offset of + * the LLC header. * * To check for Ethernet types, we assume that SSAP = SNAP * is being used and pick out the encapsulated Ethernet type. @@ -1132,7 +1157,7 @@ init_linktype(p) * header or an AVS header, so, in practice, it's * variable-length. */ - off_linktype = 24; + off_linktype.constant_part = 24; off_linkpl.constant_part = 0; /* link-layer header is variable-length */ off_linkpl.is_variable = 1; off_nl = 8; /* 802.2+SNAP */ @@ -1149,7 +1174,7 @@ init_linktype(p) * the encapsulated DLT should be DLT_IEEE802_11) we * generate code to check for this too. */ - off_linktype = 24; + off_linktype.constant_part = 24; off_linkpl.constant_part = 0; /* link-layer header is variable-length */ off_linkpl.is_variable = 1; off_linkhdr.is_variable = 1; @@ -1170,7 +1195,7 @@ init_linktype(p) * or "pppoa and tcp port 80" and have it check for * PPPo{A,E} and a PPP protocol of IP and.... */ - off_linktype = 0; + off_linktype.constant_part = 0; off_linkpl.constant_part = 0; /* packet begins with LLC header */ off_nl = 8; /* 802.2+SNAP */ off_nl_nosnap = 3; /* 802.2 */ @@ -1186,7 +1211,7 @@ init_linktype(p) off_vci = SUNATM_VCI_POS; off_proto = PROTO_POS; off_payload = SUNATM_PKT_BEGIN_POS; - off_linktype = off_payload; + off_linktype.constant_part = off_payload; off_linkpl.constant_part = off_payload; /* if LLC-encapsulated */ off_nl = 8; /* 802.2+SNAP */ off_nl_nosnap = 3; /* 802.2 */ @@ -1195,14 +1220,14 @@ init_linktype(p) case DLT_RAW: case DLT_IPV4: case DLT_IPV6: - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = 0; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ break; case DLT_LINUX_SLL: /* fake header for Linux cooked socket */ - off_linktype = 14; + off_linktype.constant_part = 14; off_linkpl.constant_part = 16; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ @@ -1214,7 +1239,7 @@ init_linktype(p) * but really it just indicates whether there is a "short" or * "long" DDP packet following. */ - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = 0; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ @@ -1231,7 +1256,7 @@ init_linktype(p) * XXX - should we generate code to check for SNAP? RFC * 2625 says SNAP should be used. */ - off_linktype = 16; + off_linktype.constant_part = 16; off_linkpl.constant_part = 16; off_nl = 8; /* 802.2+SNAP */ off_nl_nosnap = 3; /* 802.2 */ @@ -1242,7 +1267,7 @@ init_linktype(p) * XXX - we should set this to handle SNAP-encapsulated * frames (NLPID of 0x80). */ - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = 0; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ @@ -1254,21 +1279,21 @@ init_linktype(p) * so lets start with offset 4 for now and increments later on (FIXME); */ case DLT_MFR: - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = 0; off_nl = 4; off_nl_nosnap = 0; /* XXX - for now -> no 802.2 LLC */ break; case DLT_APPLE_IP_OVER_IEEE1394: - off_linktype = 16; + off_linktype.constant_part = 16; off_linkpl.constant_part = 18; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ break; case DLT_SYMANTEC_FIREWALL: - off_linktype = 6; + off_linktype.constant_part = 6; off_linkpl.constant_part = 44; off_nl = 0; /* Ethernet II */ off_nl_nosnap = 0; /* XXX - what does it do with 802.3 packets? */ @@ -1276,7 +1301,7 @@ init_linktype(p) #ifdef HAVE_NET_PFVAR_H case DLT_PFLOG: - off_linktype = 0; + off_linktype.constant_part = 0; off_linkpl.constant_part = PFLOG_HDRLEN; off_nl = 0; off_nl_nosnap = 0; /* no 802.2 LLC */ @@ -1289,21 +1314,21 @@ init_linktype(p) case DLT_JUNIPER_PPP: case DLT_JUNIPER_CHDLC: case DLT_JUNIPER_FRELAY: - off_linktype = 4; + off_linktype.constant_part = 4; off_linkpl.constant_part = 4; off_nl = 0; off_nl_nosnap = -1; /* no 802.2 LLC */ break; case DLT_JUNIPER_ATM1: - off_linktype = 4; /* in reality variable between 4-8 */ + off_linktype.constant_part = 4; /* in reality variable between 4-8 */ off_linkpl.constant_part = 4; /* in reality variable between 4-8 */ off_nl = 0; off_nl_nosnap = 10; break; case DLT_JUNIPER_ATM2: - off_linktype = 8; /* in reality variable between 8-12 */ + off_linktype.constant_part = 8; /* in reality variable between 8-12 */ off_linkpl.constant_part = 8; /* in reality variable between 8-12 */ off_nl = 0; off_nl_nosnap = 10; @@ -1314,69 +1339,69 @@ init_linktype(p) case DLT_JUNIPER_PPPOE: case DLT_JUNIPER_ETHER: off_linkpl.constant_part = 14; - off_linktype = 16; + off_linktype.constant_part = 16; off_nl = 18; /* Ethernet II */ off_nl_nosnap = 21; /* 802.3+802.2 */ break; case DLT_JUNIPER_PPPOE_ATM: - off_linktype = 4; + off_linktype.constant_part = 4; off_linkpl.constant_part = 6; off_nl = 0; off_nl_nosnap = -1; /* no 802.2 LLC */ break; case DLT_JUNIPER_GGSN: - off_linktype = 6; + off_linktype.constant_part = 6; off_linkpl.constant_part = 12; off_nl = 0; off_nl_nosnap = -1; /* no 802.2 LLC */ break; case DLT_JUNIPER_ES: - off_linktype = 6; + off_linktype.constant_part = 6; off_linkpl.constant_part = -1; /* not really a network layer but raw IP addresses */ off_nl = -1; /* not really a network layer but raw IP addresses */ off_nl_nosnap = -1; /* no 802.2 LLC */ break; case DLT_JUNIPER_MONITOR: - off_linktype = 12; + off_linktype.constant_part = 12; off_linkpl.constant_part = 12; off_nl = 0; /* raw IP/IP6 header */ off_nl_nosnap = -1; /* no 802.2 LLC */ break; case DLT_BACNET_MS_TP: - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; break; case DLT_JUNIPER_SERVICES: - off_linktype = 12; + off_linktype.constant_part = 12; off_linkpl.constant_part = -1; /* L3 proto location dep. on cookie type */ off_nl = -1; /* L3 proto location dep. on cookie type */ off_nl_nosnap = -1; /* no 802.2 LLC */ break; case DLT_JUNIPER_VP: - off_linktype = 18; + off_linktype.constant_part = 18; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; break; case DLT_JUNIPER_ST: - off_linktype = 18; + off_linktype.constant_part = 18; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; break; case DLT_JUNIPER_ISM: - off_linktype = 8; + off_linktype.constant_part = 8; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; @@ -1386,7 +1411,7 @@ init_linktype(p) case DLT_JUNIPER_SRX_E2E: case DLT_JUNIPER_FIBRECHANNEL: case DLT_JUNIPER_ATM_CEMIC: - off_linktype = 8; + off_linktype.constant_part = 8; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; @@ -1399,7 +1424,7 @@ init_linktype(p) off_opc = 4; off_dpc = 4; off_sls = 7; - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; @@ -1412,7 +1437,7 @@ init_linktype(p) off_opc = 8; off_dpc = 8; off_sls = 11; - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; @@ -1425,14 +1450,14 @@ init_linktype(p) off_opc = 24; off_dpc = 24; off_sls = 27; - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; break; case DLT_PFSYNC: - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = 4; off_nl = 0; off_nl_nosnap = 0; @@ -1442,14 +1467,14 @@ init_linktype(p) /* * Currently, only raw "link[N:M]" filtering is supported. */ - off_linktype = -1; /* variable, min 15, max 71 steps of 7 */ + off_linktype.constant_part = -1; /* variable, min 15, max 71 steps of 7 */ off_linkpl.constant_part = -1; off_nl = -1; /* variable, min 16, max 71 steps of 7 */ off_nl_nosnap = -1; /* no 802.2 LLC */ break; case DLT_IPNET: - off_linktype = 1; + off_linktype.constant_part = 1; off_linkpl.constant_part = 24; /* ipnet header length */ off_nl = 0; off_nl_nosnap = -1; @@ -1457,7 +1482,7 @@ init_linktype(p) case DLT_NETANALYZER: off_linkhdr.constant_part = 4; /* Ethernet header is past 4-byte pseudo-header */ - off_linktype = 12; + off_linktype.constant_part = off_linkhdr.constant_part + 12; off_linkpl.constant_part = off_linkhdr.constant_part + 14; /* pseudo-header+Ethernet header length */ off_nl = 0; /* Ethernet II */ off_nl_nosnap = 3; /* 802.3+802.2 */ @@ -1465,7 +1490,7 @@ init_linktype(p) case DLT_NETANALYZER_TRANSPARENT: off_linkhdr.constant_part = 12; /* MAC header is past 4-byte pseudo-header, preamble, and SFD */ - off_linktype = 12; + off_linktype.constant_part = off_linkhdr.constant_part + 12; off_linkpl.constant_part = off_linkhdr.constant_part + 14; /* pseudo-header+preamble+SFD+Ethernet header length */ off_nl = 0; /* Ethernet II */ off_nl_nosnap = 3; /* 802.3+802.2 */ @@ -1478,7 +1503,7 @@ init_linktype(p) */ if (linktype >= DLT_MATCHING_MIN && linktype <= DLT_MATCHING_MAX) { - off_linktype = -1; + off_linktype.constant_part = -1; off_linkpl.constant_part = -1; off_nl = -1; off_nl_nosnap = -1; @@ -1571,6 +1596,10 @@ gen_load_a(offrel, offset, size) s = gen_load_absoffsetrel(&off_linkpl, off_nl_nosnap + offset, size); break; + case OR_LINKTYPE: + s = gen_load_absoffsetrel(&off_linktype, offset, size); + break; + case OR_TRAN_IPV4: /* * Load the X register with the length of the IPv4 header @@ -1630,7 +1659,7 @@ gen_loadx_iphdrlen() * the value from the X register. */ s2 = new_stmt(BPF_LD|BPF_IND|BPF_B); - s2->s.k = off_nl; + s2->s.k = off_linkpl.constant_part + off_nl; sappend(s, s2); s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K); s2->s.k = 0xf; @@ -1733,7 +1762,7 @@ gen_ether_linktype(proto) * DSAP, as we do for other types <= ETHERMTU * (i.e., other SAP values)? */ - b0 = gen_cmp_gt(OR_LINKHDR, off_linktype, BPF_H, ETHERMTU); + b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU); gen_not(b0); b1 = gen_cmp(OR_LLC, 0, BPF_H, (bpf_int32) ((proto << 8) | proto)); @@ -1788,7 +1817,7 @@ gen_ether_linktype(proto) * Now we generate code to check for 802.3 * frames in general. */ - b0 = gen_cmp_gt(OR_LINKHDR, off_linktype, BPF_H, ETHERMTU); + b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU); gen_not(b0); /* @@ -1804,8 +1833,7 @@ gen_ether_linktype(proto) * do that before checking for the other frame * types. */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, - (bpf_int32)ETHERTYPE_IPX); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)ETHERTYPE_IPX); gen_or(b0, b1); return b1; @@ -1821,7 +1849,7 @@ gen_ether_linktype(proto) * we check for an Ethernet type field less than * 1500, which means it's an 802.3 length field. */ - b0 = gen_cmp_gt(OR_LINKHDR, off_linktype, BPF_H, ETHERMTU); + b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU); gen_not(b0); /* @@ -1846,7 +1874,7 @@ gen_ether_linktype(proto) * phase 1?); we just check for the Ethernet * protocol type. */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, (bpf_int32)proto); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto); gen_or(b0, b1); return b1; @@ -1861,10 +1889,9 @@ gen_ether_linktype(proto) * a length field, <= ETHERMTU) and * then check the DSAP. */ - b0 = gen_cmp_gt(OR_LINKHDR, off_linktype, BPF_H, ETHERMTU); + b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU); gen_not(b0); - b1 = gen_cmp(OR_LINKHDR, off_linktype + 2, BPF_B, - (bpf_int32)proto); + b1 = gen_cmp(OR_LINKTYPE, 2, BPF_B, (bpf_int32)proto); gen_and(b0, b1); return b1; } else { @@ -1877,7 +1904,7 @@ gen_ether_linktype(proto) * will fail and the frame won't match, * which is what we want). */ - return gen_cmp(OR_LINKHDR, off_linktype, BPF_H, + return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto); } } @@ -1894,12 +1921,11 @@ gen_ipnet_linktype(proto) switch (proto) { case ETHERTYPE_IP: - return gen_cmp(OR_LINKHDR, off_linktype, BPF_B, - (bpf_int32)IPH_AF_INET); + return gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)IPH_AF_INET); /* NOTREACHED */ case ETHERTYPE_IPV6: - return gen_cmp(OR_LINKHDR, off_linktype, BPF_B, + return gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)IPH_AF_INET6); /* NOTREACHED */ @@ -1941,7 +1967,7 @@ gen_linux_sll_linktype(proto) * DSAP, as we do for other types <= ETHERMTU * (i.e., other SAP values)? */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, LINUX_SLL_P_802_2); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2); b1 = gen_cmp(OR_LLC, 0, BPF_H, (bpf_int32) ((proto << 8) | proto)); gen_and(b0, b1); @@ -1976,14 +2002,14 @@ gen_linux_sll_linktype(proto) b0 = gen_cmp(OR_LLC, 0, BPF_B, (bpf_int32)LLCSAP_IPX); b1 = gen_snap(0x000000, ETHERTYPE_IPX); gen_or(b0, b1); - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, LINUX_SLL_P_802_2); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2); gen_and(b0, b1); /* * Now check for 802.3 frames and OR that with * the previous test. */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, LINUX_SLL_P_802_3); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_3); gen_or(b0, b1); /* @@ -1991,8 +2017,7 @@ gen_linux_sll_linktype(proto) * do that before checking for the other frame * types. */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, - (bpf_int32)ETHERTYPE_IPX); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)ETHERTYPE_IPX); gen_or(b0, b1); return b1; @@ -2008,7 +2033,7 @@ gen_linux_sll_linktype(proto) * we check for the 802.2 protocol type in the * "Ethernet type" field. */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, LINUX_SLL_P_802_2); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2); /* * 802.2-encapsulated ETHERTYPE_ATALK packets are @@ -2032,7 +2057,7 @@ gen_linux_sll_linktype(proto) * phase 1?); we just check for the Ethernet * protocol type. */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, (bpf_int32)proto); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto); gen_or(b0, b1); return b1; @@ -2046,8 +2071,7 @@ gen_linux_sll_linktype(proto) * in the "Ethernet type" field, and * then check the DSAP. */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, - LINUX_SLL_P_802_2); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, LINUX_SLL_P_802_2); b1 = gen_cmp(OR_LINKHDR, off_linkpl.constant_part, BPF_B, (bpf_int32)proto); gen_and(b0, b1); @@ -2062,8 +2086,7 @@ gen_linux_sll_linktype(proto) * will fail and the frame won't match, * which is what we want). */ - return gen_cmp(OR_LINKHDR, off_linktype, BPF_H, - (bpf_int32)proto); + return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto); } } } @@ -2574,6 +2597,15 @@ insert_compute_vloffsets(b) { struct slist *s; + /* There is an implicit dependency between the link + * payload and link header since the payload computation + * includes the variable part of the header. Therefore, + * if nobody else has allocated a register for the link + * header and we need it, do it now. */ + if (off_linkpl.reg != -1 && off_linkhdr.is_variable && + off_linkhdr.reg == -1) + off_linkhdr.reg = alloc_reg(); + /* * For link-layer types that have a variable-length header * preceding the link-layer header, generate code to load @@ -2766,6 +2798,9 @@ gen_prevlinkhdr_check(void) { struct block *b0; + if (is_geneve) + return gen_geneve_ll_check(); + switch (prevlinktype) { case DLT_SUNATM: @@ -2827,7 +2862,13 @@ gen_linktype(proto) case DLT_EN10MB: case DLT_NETANALYZER: case DLT_NETANALYZER_TRANSPARENT: - b0 = gen_prevlinkhdr_check(); + /* Geneve has an EtherType regardless of whether there is an + * L2 header. */ + if (!is_geneve) + b0 = gen_prevlinkhdr_check(); + else + b0 = NULL; + b1 = gen_ether_linktype(proto); if (b0 != NULL) gen_and(b0, b1); @@ -2843,8 +2884,7 @@ gen_linktype(proto) /* fall through */ default: - return gen_cmp(OR_LINKHDR, off_linktype, BPF_H, - (bpf_int32)proto); + return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto); /*NOTREACHED*/ break; } @@ -2971,7 +3011,7 @@ gen_linktype(proto) * map them to the corresponding PPP protocol types. */ proto = ethertype_to_ppptype(proto); - return gen_cmp(OR_LINKHDR, off_linktype, BPF_H, (bpf_int32)proto); + return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto); /*NOTREACHED*/ break; @@ -2987,16 +3027,16 @@ gen_linktype(proto) * Also check for Van Jacobson-compressed IP. * XXX - do this for other forms of PPP? */ - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, PPP_IP); - b1 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, PPP_VJC); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, PPP_IP); + b1 = gen_cmp(OR_LINKTYPE, 0, BPF_H, PPP_VJC); gen_or(b0, b1); - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_H, PPP_VJNC); + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_H, PPP_VJNC); gen_or(b1, b0); return b0; default: proto = ethertype_to_ppptype(proto); - return gen_cmp(OR_LINKHDR, off_linktype, BPF_H, + return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto); } /*NOTREACHED*/ @@ -3097,31 +3137,31 @@ gen_linktype(proto) return gen_false(); case ETHERTYPE_IPV6: - return (gen_cmp(OR_LINKHDR, off_linktype, BPF_B, + return (gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)ARCTYPE_INET6)); case ETHERTYPE_IP: - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_B, + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)ARCTYPE_IP); - b1 = gen_cmp(OR_LINKHDR, off_linktype, BPF_B, + b1 = gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)ARCTYPE_IP_OLD); gen_or(b0, b1); return (b1); case ETHERTYPE_ARP: - b0 = gen_cmp(OR_LINKHDR, off_linktype, BPF_B, + b0 = gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)ARCTYPE_ARP); - b1 = gen_cmp(OR_LINKHDR, off_linktype, BPF_B, + b1 = gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)ARCTYPE_ARP_OLD); gen_or(b0, b1); return (b1); case ETHERTYPE_REVARP: - return (gen_cmp(OR_LINKHDR, off_linktype, BPF_B, + return (gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)ARCTYPE_REVARP)); case ETHERTYPE_ATALK: - return (gen_cmp(OR_LINKHDR, off_linktype, BPF_B, + return (gen_cmp(OR_LINKTYPE, 0, BPF_B, (bpf_int32)ARCTYPE_ATALK)); } /*NOTREACHED*/ @@ -3286,16 +3326,16 @@ gen_linktype(proto) /* * Does this link-layer header type have a field * indicating the type of the next protocol? If - * so, off_linktype will be the offset of that + * so, off_linktype.constant_part will be the offset of that * field in the packet; if not, it will be -1. */ - if (off_linktype != (u_int)-1) { + if (off_linktype.constant_part != (u_int)-1) { /* * Yes; assume it's an Ethernet type. (If * it's not, it needs to be handled specially * above.) */ - return gen_cmp(OR_LINKHDR, off_linktype, BPF_H, (bpf_int32)proto); + return gen_cmp(OR_LINKTYPE, 0, BPF_H, (bpf_int32)proto); } else { /* * No; report an error. @@ -3353,7 +3393,7 @@ gen_llc(void) * We check for an Ethernet type field less than * 1500, which means it's an 802.3 length field. */ - b0 = gen_cmp_gt(OR_LINKHDR, off_linktype, BPF_H, ETHERMTU); + b0 = gen_cmp_gt(OR_LINKTYPE, 0, BPF_H, ETHERMTU); gen_not(b0); /* @@ -5548,15 +5588,8 @@ gen_protochain(v, proto, dir) * branches, and backward branch support is unlikely to appear * in kernel BPF engines.) */ - switch (linktype) { - - case DLT_IEEE802_11: - case DLT_PRISM_HEADER: - case DLT_IEEE802_11_RADIO_AVS: - case DLT_IEEE802_11_RADIO: - case DLT_PPI: - bpf_error("'protochain' not supported with 802.11"); - } + if (off_linkpl.is_variable) + bpf_error("'protochain' not supported with variable length headers"); no_optimize = 1; /*this code is not compatible with optimzer yet */ @@ -6168,7 +6201,8 @@ gen_scode(name, q) if (alist == NULL || *alist == NULL) bpf_error("unknown host '%s'", name); tproto = proto; - if (off_linktype == (u_int)-1 && tproto == Q_DEFAULT) + if (off_linktype.constant_part == (u_int)-1 && + tproto == Q_DEFAULT) tproto = Q_IP; b = gen_host(**alist++, 0xffffffff, tproto, dir, q.addr); while (*alist) { @@ -6186,7 +6220,8 @@ gen_scode(name, q) ai = res; b = tmp = NULL; tproto = tproto6 = proto; - if (off_linktype == -1 && tproto == Q_DEFAULT) { + if (off_linktype.constant_part == -1 && + tproto == Q_DEFAULT) { tproto = Q_IP; tproto6 = Q_IPV6; } @@ -6992,6 +7027,17 @@ gen_arth(code, a0, a1) { struct slist *s0, *s1, *s2; + /* + * Disallow division by, or modulus by, zero; we do this here + * so that it gets done even if the optimizer is disabled. + */ + if (code == BPF_DIV) { + if (a1->s->s.code == (BPF_LD|BPF_IMM) && a1->s->s.k == 0) + bpf_error("division by zero"); + } else if (code == BPF_MOD) { + if (a1->s->s.code == (BPF_LD|BPF_IMM) && a1->s->s.k == 0) + bpf_error("modulus by zero"); + } s0 = xfer_to_x(a1); s1 = xfer_to_a(a0); s2 = new_stmt(BPF_ALU|BPF_X|code); @@ -7891,7 +7937,7 @@ gen_vlan_no_bpf_extensions(int vlan_num) * The link-layer type information follows the VLAN tags, so * skip past this VLAN tag. */ - off_linktype += 4; + off_linktype.constant_part += 4; return b0; } @@ -7946,7 +7992,11 @@ gen_vlan(vlan_num) case DLT_NETANALYZER: case DLT_NETANALYZER_TRANSPARENT: #if defined(SKF_AD_VLAN_TAG) && defined(SKF_AD_VLAN_TAG_PRESENT) - if (vlan_stack_depth == 0) { + /* Verify that this is the outer part of the packet and + * not encapsulated somehow. */ + if (vlan_stack_depth == 0 && !off_linkhdr.is_variable && + off_linkhdr.constant_part == + off_outermostlinkhdr.constant_part) { /* * Do we need special VLAN handling? */ @@ -8121,7 +8171,7 @@ gen_pppoes(sess_num) off_linkpl.constant_part + off_nl + 6, /* 6 bytes past the PPPoE header */ off_linkpl.reg); - off_linktype = 0; + off_linktype = off_linkhdr; off_linkpl.constant_part = off_linkhdr.constant_part + 2; off_nl = 0; @@ -8130,6 +8180,300 @@ gen_pppoes(sess_num) return b0; } +/* Check that this is Geneve and the VNI is correct if + * specified. Parameterized to handle both IPv4 and IPv6. */ +static struct block * +gen_geneve_check(struct block *(*gen_portfn)(int, int, int), + enum e_offrel offrel, int vni) +{ + struct block *b0, *b1; + + b0 = gen_portfn(GENEVE_PORT, IPPROTO_UDP, Q_DST); + + /* Check that we are operating on version 0. Otherwise, we + * can't decode the rest of the fields. The version is 2 bits + * in the first byte of the Geneve header. */ + b1 = gen_mcmp(offrel, 8, BPF_B, (bpf_int32)0, 0xc0); + gen_and(b0, b1); + b0 = b1; + + if (vni >= 0) { + vni <<= 8; /* VNI is in the upper 3 bytes */ + b1 = gen_mcmp(offrel, 12, BPF_W, (bpf_int32)vni, + 0xffffff00); + gen_and(b0, b1); + b0 = b1; + } + + return b0; +} + +/* The IPv4 and IPv6 Geneve checks need to do two things: + * - Verify that this actually is Geneve with the right VNI. + * - Place the IP header length (plus variable link prefix if + * needed) into register A to be used later to compute + * the inner packet offsets. */ +static struct block * +gen_geneve4(int vni) +{ + struct block *b0, *b1; + struct slist *s, *s1; + + b0 = gen_geneve_check(gen_port, OR_TRAN_IPV4, vni); + + /* Load the IP header length into A. */ + s = gen_loadx_iphdrlen(); + + s1 = new_stmt(BPF_MISC|BPF_TXA); + sappend(s, s1); + + /* Forcibly append these statements to the true condition + * of the protocol check by creating a new block that is + * always true and ANDing them. */ + b1 = new_block(BPF_JMP|BPF_JEQ|BPF_X); + b1->stmts = s; + b1->s.k = 0; + + gen_and(b0, b1); + + return b1; +} + +static struct block * +gen_geneve6(int vni) +{ + struct block *b0, *b1; + struct slist *s, *s1; + + b0 = gen_geneve_check(gen_port6, OR_TRAN_IPV6, vni); + + /* Load the IP header length. We need to account for a + * variable length link prefix if there is one. */ + s = gen_abs_offset_varpart(&off_linkpl); + if (s) { + s1 = new_stmt(BPF_LD|BPF_IMM); + s1->s.k = 40; + sappend(s, s1); + + s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_X); + s1->s.k = 0; + sappend(s, s1); + } else { + s = new_stmt(BPF_LD|BPF_IMM); + s->s.k = 40;; + } + + /* Forcibly append these statements to the true condition + * of the protocol check by creating a new block that is + * always true and ANDing them. */ + s1 = new_stmt(BPF_MISC|BPF_TAX); + sappend(s, s1); + + b1 = new_block(BPF_JMP|BPF_JEQ|BPF_X); + b1->stmts = s; + b1->s.k = 0; + + gen_and(b0, b1); + + return b1; +} + +/* We need to store three values based on the Geneve header:: + * - The offset of the linktype. + * - The offset of the end of the Geneve header. + * - The offset of the end of the encapsulated MAC header. */ +static struct slist * +gen_geneve_offsets(void) +{ + struct slist *s, *s1, *s_proto; + + /* First we need to calculate the offset of the Geneve header + * itself. This is composed of the IP header previously calculated + * (include any variable link prefix) and stored in A plus the + * fixed sized headers (fixed link prefix, MAC length, and UDP + * header). */ + s = new_stmt(BPF_ALU|BPF_ADD|BPF_K); + s->s.k = off_linkpl.constant_part + off_nl + 8; + + /* Stash this in X since we'll need it later. */ + s1 = new_stmt(BPF_MISC|BPF_TAX); + sappend(s, s1); + + /* The EtherType in Geneve is 2 bytes in. Calculate this and + * store it. */ + s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_K); + s1->s.k = 2; + sappend(s, s1); + + off_linktype.reg = alloc_reg(); + off_linktype.is_variable = 1; + off_linktype.constant_part = 0; + + s1 = new_stmt(BPF_ST); + s1->s.k = off_linktype.reg; + sappend(s, s1); + + /* Load the Geneve option length and mask and shift to get the + * number of bytes. It is stored in the first byte of the Geneve + * header. */ + s1 = new_stmt(BPF_LD|BPF_IND|BPF_B); + s1->s.k = 0; + sappend(s, s1); + + s1 = new_stmt(BPF_ALU|BPF_AND|BPF_K); + s1->s.k = 0x3f; + sappend(s, s1); + + s1 = new_stmt(BPF_ALU|BPF_MUL|BPF_K); + s1->s.k = 4; + sappend(s, s1); + + /* Add in the rest of the Geneve base header. */ + s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_K); + s1->s.k = 8; + sappend(s, s1); + + /* Add the Geneve header length to its offset and store. */ + s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_X); + s1->s.k = 0; + sappend(s, s1); + + /* Set the encapsulated type as Ethernet. Even though we may + * not actually have Ethernet inside there are two reasons this + * is useful: + * - The linktype field is always in EtherType format regardless + * of whether it is in Geneve or an inner Ethernet frame. + * - The only link layer that we have specific support for is + * Ethernet. We will confirm that the packet actually is + * Ethernet at runtime before executing these checks. */ + PUSH_LINKHDR(DLT_EN10MB, 1, 0, alloc_reg()); + + s1 = new_stmt(BPF_ST); + s1->s.k = off_linkhdr.reg; + sappend(s, s1); + + /* Calculate whether we have an Ethernet header or just raw IP/ + * MPLS/etc. If we have Ethernet, advance the end of the MAC offset + * and linktype by 14 bytes so that the network header can be found + * seamlessly. Otherwise, keep what we've calculated already. */ + + /* We have a bare jmp so we can't use the optimizer. */ + no_optimize = 1; + + /* Load the EtherType in the Geneve header, 2 bytes in. */ + s1 = new_stmt(BPF_LD|BPF_IND|BPF_H); + s1->s.k = 2; + sappend(s, s1); + + /* Load X with the end of the Geneve header. */ + s1 = new_stmt(BPF_LDX|BPF_MEM); + s1->s.k = off_linkhdr.reg; + sappend(s, s1); + + /* Check if the EtherType is Transparent Ethernet Bridging. At the + * end of this check, we should have the total length in X. In + * the non-Ethernet case, it's already there. */ + s_proto = new_stmt(JMP(BPF_JEQ)); + s_proto->s.k = ETHERTYPE_TEB; + sappend(s, s_proto); + + s1 = new_stmt(BPF_MISC|BPF_TXA); + sappend(s, s1); + s_proto->s.jt = s1; + + /* Since this is Ethernet, use the EtherType of the payload + * directly as the linktype. Overwrite what we already have. */ + s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_K); + s1->s.k = 12; + sappend(s, s1); + + s1 = new_stmt(BPF_ST); + s1->s.k = off_linktype.reg; + sappend(s, s1); + + /* Advance two bytes further to get the end of the Ethernet + * header. */ + s1 = new_stmt(BPF_ALU|BPF_ADD|BPF_K); + s1->s.k = 2; + sappend(s, s1); + + /* Move the result to X. */ + s1 = new_stmt(BPF_MISC|BPF_TAX); + sappend(s, s1); + + /* Store the final result of our linkpl calculation. */ + off_linkpl.reg = alloc_reg(); + off_linkpl.is_variable = 1; + off_linkpl.constant_part = 0; + + s1 = new_stmt(BPF_STX); + s1->s.k = off_linkpl.reg; + sappend(s, s1); + s_proto->s.jf = s1; + + off_nl = 0; + + return s; +} + +/* Check to see if this is a Geneve packet. */ +struct block * +gen_geneve(int vni) +{ + struct block *b0, *b1; + struct slist *s; + + b0 = gen_geneve4(vni); + b1 = gen_geneve6(vni); + + gen_or(b0, b1); + b0 = b1; + + /* Later filters should act on the payload of the Geneve frame, + * update all of the header pointers. Attach this code so that + * it gets executed in the event that the Geneve filter matches. */ + s = gen_geneve_offsets(); + + b1 = gen_true(); + sappend(s, b1->stmts); + b1->stmts = s; + + gen_and(b0, b1); + + is_geneve = 1; + + return b1; +} + +/* Check that the encapsulated frame has a link layer header + * for Ethernet filters. */ +static struct block * +gen_geneve_ll_check() +{ + struct block *b0; + struct slist *s, *s1; + + /* The easiest way to see if there is a link layer present + * is to check if the link layer header and payload are not + * the same. */ + + /* Geneve always generates pure variable offsets so we can + * compare only the registers. */ + s = new_stmt(BPF_LD|BPF_MEM); + s->s.k = off_linkhdr.reg; + + s1 = new_stmt(BPF_LDX|BPF_MEM); + s1->s.k = off_linkpl.reg; + sappend(s, s1); + + b0 = new_block(BPF_JMP|BPF_JEQ|BPF_X); + b0->stmts = s; + b0->s.k = 0; + gen_not(b0); + + return b0; +} + struct block * gen_atmfield_code(atmfield, jvalue, jtype, reverse) int atmfield; @@ -8267,7 +8611,7 @@ gen_atmtype_abbrev(type) PUSH_LINKHDR(DLT_EN10MB, 0, off_payload + 2, /* Ethernet header */ -1); - off_linktype = 12; + off_linktype.constant_part = off_linkhdr.constant_part + 12; off_linkpl.constant_part = off_linkhdr.constant_part + 14; /* Ethernet */ off_nl = 0; /* Ethernet II */ off_nl_nosnap = 3; /* 802.3+802.2 */