diff options
Diffstat (limited to 'net/core/ptp_classifier.c')
| -rw-r--r-- | net/core/ptp_classifier.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/net/core/ptp_classifier.c b/net/core/ptp_classifier.c new file mode 100644 index 00000000000..eaba0f68f86 --- /dev/null +++ b/net/core/ptp_classifier.c @@ -0,0 +1,141 @@ +/* PTP classifier + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +/* The below program is the bpf_asm (tools/net/) representation of + * the opcode array in the ptp_filter structure. + * + * For convenience, this can easily be altered and reviewed with + * bpf_asm and bpf_dbg, e.g. `./bpf_asm -c prog` where prog is a + * simple file containing the below program: + * + * ldh [12] ; load ethertype + * + * ; PTP over UDP over IPv4 over Ethernet + * test_ipv4: + * jneq #0x800, test_ipv6 ; ETH_P_IP ? + * ldb [23] ; load proto + * jneq #17, drop_ipv4 ; IPPROTO_UDP ? + * ldh [20] ; load frag offset field + * jset #0x1fff, drop_ipv4 ; don't allow fragments + * ldxb 4*([14]&0xf) ; load IP header len + * ldh [x + 16] ; load UDP dst port + * jneq #319, drop_ipv4 ; is port PTP_EV_PORT ? + * ldh [x + 22] ; load payload + * and #0xf ; mask PTP_CLASS_VMASK + * or #0x10 ; PTP_CLASS_IPV4 + * ret a ; return PTP class + * drop_ipv4: ret #0x0 ; PTP_CLASS_NONE + * + * ; PTP over UDP over IPv6 over Ethernet + * test_ipv6: + * jneq #0x86dd, test_8021q ; ETH_P_IPV6 ? + * ldb [20] ; load proto + * jneq #17, drop_ipv6 ; IPPROTO_UDP ? + * ldh [56] ; load UDP dst port + * jneq #319, drop_ipv6 ; is port PTP_EV_PORT ? + * ldh [62] ; load payload + * and #0xf ; mask PTP_CLASS_VMASK + * or #0x20 ; PTP_CLASS_IPV6 + * ret a ; return PTP class + * drop_ipv6: ret #0x0 ; PTP_CLASS_NONE + * + * ; PTP over 802.1Q over Ethernet + * test_8021q: + * jneq #0x8100, test_ieee1588 ; ETH_P_8021Q ? + * ldh [16] ; load inner type + * jneq #0x88f7, drop_ieee1588 ; ETH_P_1588 ? + * ldb [18] ; load payload + * and #0x8 ; as we don't have ports here, test + * jneq #0x0, drop_ieee1588 ; for PTP_GEN_BIT and drop these + * ldh [18] ; reload payload + * and #0xf ; mask PTP_CLASS_VMASK + * or #0x40 ; PTP_CLASS_V2_VLAN + * ret a ; return PTP class + * + * ; PTP over Ethernet + * test_ieee1588: + * jneq #0x88f7, drop_ieee1588 ; ETH_P_1588 ? + * ldb [14] ; load payload + * and #0x8 ; as we don't have ports here, test + * jneq #0x0, drop_ieee1588 ; for PTP_GEN_BIT and drop these + * ldh [14] ; reload payload + * and #0xf ; mask PTP_CLASS_VMASK + * or #0x30 ; PTP_CLASS_L2 + * ret a ; return PTP class + * drop_ieee1588: ret #0x0 ; PTP_CLASS_NONE + */ + +#include <linux/skbuff.h> +#include <linux/filter.h> +#include <linux/ptp_classify.h> + +static struct sk_filter *ptp_insns __read_mostly; + +unsigned int ptp_classify_raw(const struct sk_buff *skb) +{ + return SK_RUN_FILTER(ptp_insns, skb); +} +EXPORT_SYMBOL_GPL(ptp_classify_raw); + +void __init ptp_classifier_init(void) +{ + static struct sock_filter ptp_filter[] = { + { 0x28, 0, 0, 0x0000000c }, + { 0x15, 0, 12, 0x00000800 }, + { 0x30, 0, 0, 0x00000017 }, + { 0x15, 0, 9, 0x00000011 }, + { 0x28, 0, 0, 0x00000014 }, + { 0x45, 7, 0, 0x00001fff }, + { 0xb1, 0, 0, 0x0000000e }, + { 0x48, 0, 0, 0x00000010 }, + { 0x15, 0, 4, 0x0000013f }, + { 0x48, 0, 0, 0x00000016 }, + { 0x54, 0, 0, 0x0000000f }, + { 0x44, 0, 0, 0x00000010 }, + { 0x16, 0, 0, 0x00000000 }, + { 0x06, 0, 0, 0x00000000 }, + { 0x15, 0, 9, 0x000086dd }, + { 0x30, 0, 0, 0x00000014 }, + { 0x15, 0, 6, 0x00000011 }, + { 0x28, 0, 0, 0x00000038 }, + { 0x15, 0, 4, 0x0000013f }, + { 0x28, 0, 0, 0x0000003e }, + { 0x54, 0, 0, 0x0000000f }, + { 0x44, 0, 0, 0x00000020 }, + { 0x16, 0, 0, 0x00000000 }, + { 0x06, 0, 0, 0x00000000 }, + { 0x15, 0, 9, 0x00008100 }, + { 0x28, 0, 0, 0x00000010 }, + { 0x15, 0, 15, 0x000088f7 }, + { 0x30, 0, 0, 0x00000012 }, + { 0x54, 0, 0, 0x00000008 }, + { 0x15, 0, 12, 0x00000000 }, + { 0x28, 0, 0, 0x00000012 }, + { 0x54, 0, 0, 0x0000000f }, + { 0x44, 0, 0, 0x00000040 }, + { 0x16, 0, 0, 0x00000000 }, + { 0x15, 0, 7, 0x000088f7 }, + { 0x30, 0, 0, 0x0000000e }, + { 0x54, 0, 0, 0x00000008 }, + { 0x15, 0, 4, 0x00000000 }, + { 0x28, 0, 0, 0x0000000e }, + { 0x54, 0, 0, 0x0000000f }, + { 0x44, 0, 0, 0x00000030 }, + { 0x16, 0, 0, 0x00000000 }, + { 0x06, 0, 0, 0x00000000 }, + }; + struct sock_fprog ptp_prog = { + .len = ARRAY_SIZE(ptp_filter), .filter = ptp_filter, + }; + + BUG_ON(sk_unattached_filter_create(&ptp_insns, &ptp_prog)); +} |