|  | /* 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, test_8021q_ipv4 ; 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 #0xc0                      ; PTP_CLASS_VLAN|PTP_CLASS_L2 | 
|  | *   ret a                         ; return PTP class | 
|  | * | 
|  | * ; PTP over UDP over IPv4 over 802.1Q over Ethernet | 
|  | * test_8021q_ipv4: | 
|  | *   jneq #0x800, test_8021q_ipv6  ; ETH_P_IP ? | 
|  | *   ldb [27]                      ; load proto | 
|  | *   jneq #17, drop_8021q_ipv4     ; IPPROTO_UDP ? | 
|  | *   ldh [24]                      ; load frag offset field | 
|  | *   jset #0x1fff, drop_8021q_ipv4; don't allow fragments | 
|  | *   ldxb 4*([18]&0xf)             ; load IP header len | 
|  | *   ldh [x + 20]                  ; load UDP dst port | 
|  | *   jneq #319, drop_8021q_ipv4    ; is port PTP_EV_PORT ? | 
|  | *   ldh [x + 26]                  ; load payload | 
|  | *   and #0xf                      ; mask PTP_CLASS_VMASK | 
|  | *   or #0x90                      ; PTP_CLASS_VLAN|PTP_CLASS_IPV4 | 
|  | *   ret a                         ; return PTP class | 
|  | *   drop_8021q_ipv4: ret #0x0     ; PTP_CLASS_NONE | 
|  | * | 
|  | * ; PTP over UDP over IPv6 over 802.1Q over Ethernet | 
|  | * test_8021q_ipv6: | 
|  | *   jneq #0x86dd, drop_8021q_ipv6 ; ETH_P_IPV6 ? | 
|  | *   ldb [24]                      ; load proto | 
|  | *   jneq #17, drop_8021q_ipv6           ; IPPROTO_UDP ? | 
|  | *   ldh [60]                      ; load UDP dst port | 
|  | *   jneq #319, drop_8021q_ipv6          ; is port PTP_EV_PORT ? | 
|  | *   ldh [66]                      ; load payload | 
|  | *   and #0xf                      ; mask PTP_CLASS_VMASK | 
|  | *   or #0xa0                      ; PTP_CLASS_VLAN|PTP_CLASS_IPV6 | 
|  | *   ret a                         ; return PTP class | 
|  | *   drop_8021q_ipv6: ret #0x0     ; PTP_CLASS_NONE | 
|  | * | 
|  | * ; 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 #0x40                      ; 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 bpf_prog *ptp_insns __read_mostly; | 
|  |  | 
|  | unsigned int ptp_classify_raw(const struct sk_buff *skb) | 
|  | { | 
|  | return BPF_PROG_RUN(ptp_insns, skb); | 
|  | } | 
|  | EXPORT_SYMBOL_GPL(ptp_classify_raw); | 
|  |  | 
|  | void __init ptp_classifier_init(void) | 
|  | { | 
|  | static struct sock_filter ptp_filter[] __initdata = { | 
|  | { 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, 32, 0x00008100 }, | 
|  | { 0x28,  0,  0, 0x00000010 }, | 
|  | { 0x15,  0,  7, 0x000088f7 }, | 
|  | { 0x30,  0,  0, 0x00000012 }, | 
|  | { 0x54,  0,  0, 0x00000008 }, | 
|  | { 0x15,  0, 35, 0x00000000 }, | 
|  | { 0x28,  0,  0, 0x00000012 }, | 
|  | { 0x54,  0,  0, 0x0000000f }, | 
|  | { 0x44,  0,  0, 0x000000c0 }, | 
|  | { 0x16,  0,  0, 0x00000000 }, | 
|  | { 0x15,  0, 12, 0x00000800 }, | 
|  | { 0x30,  0,  0, 0x0000001b }, | 
|  | { 0x15,  0,  9, 0x00000011 }, | 
|  | { 0x28,  0,  0, 0x00000018 }, | 
|  | { 0x45,  7,  0, 0x00001fff }, | 
|  | { 0xb1,  0,  0, 0x00000012 }, | 
|  | { 0x48,  0,  0, 0x00000014 }, | 
|  | { 0x15,  0,  4, 0x0000013f }, | 
|  | { 0x48,  0,  0, 0x0000001a }, | 
|  | { 0x54,  0,  0, 0x0000000f }, | 
|  | { 0x44,  0,  0, 0x00000090 }, | 
|  | { 0x16,  0,  0, 0x00000000 }, | 
|  | { 0x06,  0,  0, 0x00000000 }, | 
|  | { 0x15,  0,  8, 0x000086dd }, | 
|  | { 0x30,  0,  0, 0x00000018 }, | 
|  | { 0x15,  0,  6, 0x00000011 }, | 
|  | { 0x28,  0,  0, 0x0000003c }, | 
|  | { 0x15,  0,  4, 0x0000013f }, | 
|  | { 0x28,  0,  0, 0x00000042 }, | 
|  | { 0x54,  0,  0, 0x0000000f }, | 
|  | { 0x44,  0,  0, 0x000000a0 }, | 
|  | { 0x16,  0,  0, 0x00000000 }, | 
|  | { 0x06,  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, 0x00000040 }, | 
|  | { 0x16,  0,  0, 0x00000000 }, | 
|  | { 0x06,  0,  0, 0x00000000 }, | 
|  | }; | 
|  | struct sock_fprog_kern ptp_prog = { | 
|  | .len = ARRAY_SIZE(ptp_filter), .filter = ptp_filter, | 
|  | }; | 
|  |  | 
|  | BUG_ON(bpf_prog_create(&ptp_insns, &ptp_prog)); | 
|  | } |