Re: [PATCH net-next 2/2] net: filter: use block statements in tcpdump tests
From: Alexei Starovoitov <hidden>
Date: 2014-05-27 06:20:40
On Mon, May 26, 2014 at 11:17 AM, Daniel Borkmann [off-list ref] wrote:
This patch converts raw opcodes for tcpdump tests into BPF_STMT()/BPF_JUMP() combinations, which brings it into conformity with the rest of the patches and it also makes life easier to grasp what's going on in these particular test cases when they ever fail. Also arrange payload from the jump+holes test in a way as we have with other packet payloads in the test suite. Signed-off-by: Daniel Borkmann <redacted>
Acked-by: Alexei Starovoitov <redacted>
quoted hunk ↗ jump to hunk
--- lib/test_bpf.c | 143 ++++++++++++++++++++++++++++++--------------------------- 1 file changed, 75 insertions(+), 68 deletions(-)diff --git a/lib/test_bpf.c b/lib/test_bpf.c index 6be9119..3c4a1e3 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c@@ -560,30 +560,30 @@ static struct bpf_test tests[] = { { "tcpdump port 22", .u.insns = { - { 0x28, 0, 0, 0x0000000c }, - { 0x15, 0, 8, 0x000086dd }, - { 0x30, 0, 0, 0x00000014 }, - { 0x15, 2, 0, 0x00000084 }, - { 0x15, 1, 0, 0x00000006 }, - { 0x15, 0, 17, 0x00000011 }, - { 0x28, 0, 0, 0x00000036 }, - { 0x15, 14, 0, 0x00000016 }, - { 0x28, 0, 0, 0x00000038 }, - { 0x15, 12, 13, 0x00000016 }, - { 0x15, 0, 12, 0x00000800 }, - { 0x30, 0, 0, 0x00000017 }, - { 0x15, 2, 0, 0x00000084 }, - { 0x15, 1, 0, 0x00000006 }, - { 0x15, 0, 8, 0x00000011 }, - { 0x28, 0, 0, 0x00000014 }, - { 0x45, 6, 0, 0x00001fff }, - { 0xb1, 0, 0, 0x0000000e }, - { 0x48, 0, 0, 0x0000000e }, - { 0x15, 2, 0, 0x00000016 }, - { 0x48, 0, 0, 0x00000010 }, - { 0x15, 0, 1, 0x00000016 }, - { 0x06, 0, 0, 0x0000ffff }, - { 0x06, 0, 0, 0x00000000 }, + BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 12), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x86dd, 0, 8), /* IPv6 */ + BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 20), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x84, 2, 0), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 1, 0), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x11, 0, 17), + BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 54), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 14, 0), + BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 56), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 12, 13), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x0800, 0, 12), /* IPv4 */ + BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 23), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x84, 2, 0), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 1, 0), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x11, 0, 8), + BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 20), + BPF_JUMP(BPF_JMP | BPF_JSET | BPF_K, 0x1fff, 6, 0), + BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14), + BPF_STMT(BPF_LD | BPF_H | BPF_IND, 14), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 2, 0), + BPF_STMT(BPF_LD | BPF_H | BPF_IND, 16), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 0, 1), + BPF_STMT(BPF_RET | BPF_K, 0xffff), + BPF_STMT(BPF_RET | BPF_K, 0), }, CLASSIC, /* 3c:07:54:43:e5:76 > 10:bf:48:d6:43:d6, ethertype IPv4(0x0800)@@ -609,39 +609,39 @@ static struct bpf_test tests[] = { * ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0) and * (len > 115 or len < 30000000000)' -d */ - { 0x28, 0, 0, 0x0000000c }, - { 0x15, 30, 0, 0x000086dd }, - { 0x15, 0, 29, 0x00000800 }, - { 0x30, 0, 0, 0x00000017 }, - { 0x15, 0, 27, 0x00000006 }, - { 0x28, 0, 0, 0x00000014 }, - { 0x45, 25, 0, 0x00001fff }, - { 0xb1, 0, 0, 0x0000000e }, - { 0x48, 0, 0, 0x0000000e }, - { 0x15, 2, 0, 0x00000016 }, - { 0x48, 0, 0, 0x00000010 }, - { 0x15, 0, 20, 0x00000016 }, - { 0x28, 0, 0, 0x00000010 }, - { 0x02, 0, 0, 0x00000001 }, - { 0x30, 0, 0, 0x0000000e }, - { 0x54, 0, 0, 0x0000000f }, - { 0x64, 0, 0, 0x00000002 }, - { 0x07, 0, 0, 0x00000005 }, - { 0x60, 0, 0, 0x00000001 }, - { 0x1c, 0, 0, 0x00000000 }, - { 0x02, 0, 0, 0x00000005 }, - { 0xb1, 0, 0, 0x0000000e }, - { 0x50, 0, 0, 0x0000001a }, - { 0x54, 0, 0, 0x000000f0 }, - { 0x74, 0, 0, 0x00000002 }, - { 0x07, 0, 0, 0x00000009 }, - { 0x60, 0, 0, 0x00000005 }, - { 0x1d, 4, 0, 0x00000000 }, - { 0x80, 0, 0, 0x00000000 }, - { 0x25, 1, 0, 0x00000073 }, - { 0x35, 1, 0, 0xfc23ac00 }, - { 0x06, 0, 0, 0x0000ffff }, - { 0x06, 0, 0, 0x00000000 }, + BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 12), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x86dd, 30, 0), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x800, 0, 29), + BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 23), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 0, 27), + BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 20), + BPF_JUMP(BPF_JMP | BPF_JSET | BPF_K, 0x1fff, 25, 0), + BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14), + BPF_STMT(BPF_LD | BPF_H | BPF_IND, 14), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 2, 0), + BPF_STMT(BPF_LD | BPF_H | BPF_IND, 16), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 0, 20), + BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 16), + BPF_STMT(BPF_ST, 1), + BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 14), + BPF_STMT(BPF_ALU | BPF_AND | BPF_K, 0xf), + BPF_STMT(BPF_ALU | BPF_LSH | BPF_K, 2), + BPF_STMT(BPF_MISC | BPF_TAX, 0x5), /* libpcap emits K on TAX */
interesting observation. It means that libpcap doesn't init memory properly and other fields just have junk in them? and because it was doing it forever we need to accept such 'valid' instructions? Oh well. ok. Note to self: make sure to check for tidy instructions in eBPF verifier.
quoted hunk ↗ jump to hunk
+ BPF_STMT(BPF_LD | BPF_MEM, 1), + BPF_STMT(BPF_ALU | BPF_SUB | BPF_X, 0), + BPF_STMT(BPF_ST, 5), + BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14), + BPF_STMT(BPF_LD | BPF_B | BPF_IND, 26), + BPF_STMT(BPF_ALU | BPF_AND | BPF_K, 0xf0), + BPF_STMT(BPF_ALU | BPF_RSH | BPF_K, 2), + BPF_STMT(BPF_MISC | BPF_TAX, 0x9), /* libpcap emits K on TAX */ + BPF_STMT(BPF_LD | BPF_MEM, 5), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_X, 0, 4, 0), + BPF_STMT(BPF_LD | BPF_LEN, 0), + BPF_JUMP(BPF_JMP | BPF_JGT | BPF_K, 0x73, 1, 0), + BPF_JUMP(BPF_JMP | BPF_JGE | BPF_K, 0xfc23ac00, 1, 0), + BPF_STMT(BPF_RET | BPF_K, 0xffff), + BPF_STMT(BPF_RET | BPF_K, 0), }, CLASSIC, { 0x10, 0xbf, 0x48, 0xd6, 0x43, 0xd6,@@ -1453,17 +1453,24 @@ static struct bpf_test tests[] = { BPF_STMT(BPF_RET | BPF_A, 0), }, CLASSIC, - { 0x00, 0x1b, 0x21, 0x3c, 0x9d, 0xf8, 0x90, 0xe2, - 0xba, 0x0a, 0x56, 0xb4, 0x08, 0x00, 0x45, 0x00, - 0x00, 0x28, 0x00, 0x00, 0x20, 0x00, 0x40, 0x11, - 0x00, 0x00, 0xc0, 0xa8, 0x33, 0x01, 0xc0, 0xa8, - 0x33, 0x02, 0xbb, 0xb6, 0xa9, 0xfa, 0x00, 0x14, - 0x00, 0x00, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, - 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, - 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, - 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, - 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, - 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc }, + { 0x00, 0x1b, 0x21, 0x3c, 0x9d, 0xf8, + 0x90, 0xe2, 0xba, 0x0a, 0x56, 0xb4, + 0x08, 0x00, + 0x45, 0x00, 0x00, 0x28, 0x00, 0x00, + 0x20, 0x00, 0x40, 0x11, 0x00, 0x00, /* IP header */ + 0xc0, 0xa8, 0x33, 0x01, + 0xc0, 0xa8, 0x33, 0x02, + 0xbb, 0xb6, + 0xa9, 0xfa, + 0x00, 0x14, 0x00, 0x00, + 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, + 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, + 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, + 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, + 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, + 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, + 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, + 0xcc, 0xcc, 0xcc, 0xcc }, { { 88, 0x001b } } }, { --1.7.11.7