From 9cbe1f581d17baff7e93936feb041c90b29eb6a8 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:19 -0700 Subject: [PATCH 1/8] tools: bpftool: add pointer to file argument to print_hex() Make print_hex() able to print to any file instead of standard output only, and rename it to fprint_hex(). The function can now be called with the info() macro, for example, without splitting the output between standard and error outputs. Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/main.c | 8 ++++---- tools/bpf/bpftool/main.h | 2 +- tools/bpf/bpftool/map.c | 20 ++++++++++---------- tools/bpf/bpftool/prog.c | 4 ++-- 4 files changed, 17 insertions(+), 17 deletions(-) diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index e02d00d6e00b1..8662199ee050f 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -100,7 +100,7 @@ bool is_prefix(const char *pfx, const char *str) return !memcmp(str, pfx, strlen(pfx)); } -void print_hex(void *arg, unsigned int n, const char *sep) +void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep) { unsigned char *data = arg; unsigned int i; @@ -111,13 +111,13 @@ void print_hex(void *arg, unsigned int n, const char *sep) if (!i) /* nothing */; else if (!(i % 16)) - printf("\n"); + fprintf(f, "\n"); else if (!(i % 8)) - printf(" "); + fprintf(f, " "); else pfx = sep; - printf("%s%02hhx", i ? pfx : "", data[i]); + fprintf(f, "%s%02hhx", i ? pfx : "", data[i]); } } diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 844e4ef6db56f..41e6c7d3fcadb 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -67,7 +67,7 @@ enum bpf_obj_type { extern const char *bin_name; bool is_prefix(const char *pfx, const char *str); -void print_hex(void *arg, unsigned int n, const char *sep); +void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep); void usage(void) __attribute__((noreturn)); struct cmd { diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index 0528a5379e6c3..b1dad76215ed5 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -216,12 +216,12 @@ static void print_entry(struct bpf_map_info *info, unsigned char *key, !break_names; printf("key:%c", break_names ? '\n' : ' '); - print_hex(key, info->key_size, " "); + fprint_hex(stdout, key, info->key_size, " "); printf(single_line ? " " : "\n"); printf("value:%c", break_names ? '\n' : ' '); - print_hex(value, info->value_size, " "); + fprint_hex(stdout, value, info->value_size, " "); printf("\n"); } else { @@ -230,13 +230,13 @@ static void print_entry(struct bpf_map_info *info, unsigned char *key, n = get_possible_cpus(); printf("key:\n"); - print_hex(key, info->key_size, " "); + fprint_hex(stdout, key, info->key_size, " "); printf("\n"); for (i = 0; i < n; i++) { printf("value (CPU %02d):%c", i, info->value_size > 16 ? '\n' : ' '); - print_hex(value + i * info->value_size, - info->value_size, " "); + fprint_hex(stdout, value + i * info->value_size, + info->value_size, " "); printf("\n"); } } @@ -492,8 +492,8 @@ static int do_dump(int argc, char **argv) print_entry(&info, key, value); } else { info("can't lookup element with key: "); - print_hex(key, info.key_size, " "); - printf("\n"); + fprint_hex(stderr, key, info.key_size, " "); + fprintf(stderr, "\n"); } prev_key = key; @@ -587,7 +587,7 @@ static int do_lookup(int argc, char **argv) print_entry(&info, key, value); } else if (errno == ENOENT) { printf("key:\n"); - print_hex(key, info.key_size, " "); + fprint_hex(stdout, key, info.key_size, " "); printf("\n\nNot found\n"); } else { err("lookup failed: %s\n", strerror(errno)); @@ -642,14 +642,14 @@ static int do_getnext(int argc, char **argv) if (key) { printf("key:\n"); - print_hex(key, info.key_size, " "); + fprint_hex(stdout, key, info.key_size, " "); printf("\n"); } else { printf("key: None\n"); } printf("next key:\n"); - print_hex(nextkey, info.key_size, " "); + fprint_hex(stdout, nextkey, info.key_size, " "); printf("\n"); exit_free: diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index d60f5307b6e21..aa6d72ea3807b 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -224,7 +224,7 @@ static int show_prog(int fd) printf("name %s ", info.name); printf("tag "); - print_hex(info.tag, BPF_TAG_SIZE, ""); + fprint_hex(stdout, info.tag, BPF_TAG_SIZE, ""); printf("\n"); if (info.load_time) { @@ -319,7 +319,7 @@ static void dump_xlated(void *buf, unsigned int len, bool opcodes) if (opcodes) { printf(" "); - print_hex(insn + i, 8, " "); + fprint_hex(stdout, insn + i, 8, " "); printf("\n"); } From 1739c26da72c4170c86c368c75133adbb740efef Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:20 -0700 Subject: [PATCH 2/8] tools: bpftool: fix return value when all eBPF programs have been shown Change the program to have a more consistent return code. Specifically, do not make bpftool return an error code simply because it reaches the end of the list of the eBPF programs to show. Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/prog.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index aa6d72ea3807b..ede7957adcd9b 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -275,8 +275,10 @@ static int do_show(int argc, char **argv) while (true) { err = bpf_prog_get_next_id(id, &id); if (err) { - if (errno == ENOENT) + if (errno == ENOENT) { + err = 0; break; + } err("can't get next program: %s\n", strerror(errno)); if (errno == EINVAL) err("kernel too old?\n"); From 1d84487e2a2b98892c3dec7934604e9b76577aa6 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:21 -0700 Subject: [PATCH 3/8] tools: bpftool: use err() instead of info() if there are too many insns Make error messages and return codes more consistent. Specifically, replace the use of info() macro with err() when too many eBPF instructions are received to be dumped, given that bpftool returns with a non-null exit value in that case. Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/prog.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index ede7957adcd9b..6c03d2ea3f794 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -416,7 +416,7 @@ static int do_dump(int argc, char **argv) } if (*member_len > buf_size) { - info("too many instructions returned\n"); + err("too many instructions returned\n"); goto err_free; } From 9f606179c84930ada1e347b6d84bb913c8492fec Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:22 -0700 Subject: [PATCH 4/8] tools: bpftool: add `bpftool prog help` as real command i.r.t exit code Make error messages and return codes more consistent. Specifically, make `bpftool prog help` a real command, instead of printing usage by default for a non-recognized "help" command. Output is the same, but this makes bpftool return with a success value instead of an error. Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/prog.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 6c03d2ea3f794..355c14325622f 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -475,6 +475,7 @@ static int do_help(int argc, char **argv) static const struct cmd cmds[] = { { "show", do_show }, + { "help", do_help }, { "dump", do_dump }, { "pin", do_pin }, { 0 } From d9c0b48db9f4b870535b6d7255638347e770633f Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:23 -0700 Subject: [PATCH 5/8] tools: bpftool: print only one error message on byte parsing failure Make error messages more consistent. Specifically, when bpftool fails at parsing map key bytes, make it print a single error message to stderr and return from the function, instead of (always) printing a second error message afterwards. Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/map.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index b1dad76215ed5..e1004d8253924 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -252,7 +252,7 @@ static char **parse_bytes(char **argv, const char *name, unsigned char *val, val[i] = strtoul(argv[i], &endptr, 0); if (*endptr) { err("error parsing byte: %s\n", argv[i]); - break; + return NULL; } i++; } From 9e2308c133a92ff98d1397149c8483858bcf8fc0 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:24 -0700 Subject: [PATCH 6/8] tools: bpftool: print all relevant byte opcodes for "load double word" The eBPF instruction permitting to load double words (8 bytes) into a register need 8-byte long "immediate" field, and thus occupy twice the space of other instructions. bpftool was aware of this and would increment the instruction counter only once on meeting such instruction, but it would only print the first four bytes of the immediate value to load. Make it able to dump the whole 16 byte-long double instruction instead (as would `llvm-objdump -d `). Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/prog.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 355c14325622f..57edbea2fbe82 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -313,20 +313,29 @@ static void print_insn(struct bpf_verifier_env *env, const char *fmt, ...) static void dump_xlated(void *buf, unsigned int len, bool opcodes) { struct bpf_insn *insn = buf; + bool double_insn = false; unsigned int i; for (i = 0; i < len / sizeof(*insn); i++) { + if (double_insn) { + double_insn = false; + continue; + } + + double_insn = insn[i].code == (BPF_LD | BPF_IMM | BPF_DW); + printf("% 4d: ", i); print_bpf_insn(print_insn, NULL, insn + i, true); if (opcodes) { printf(" "); fprint_hex(stdout, insn + i, 8, " "); + if (double_insn && i < len - 1) { + printf(" "); + fprint_hex(stdout, insn + i + 1, 8, " "); + } printf("\n"); } - - if (insn[i].code == (BPF_LD | BPF_IMM | BPF_DW)) - i++; } } From 8dfbc6d1d213df340e5dcfdcdc76ad9407a29273 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:25 -0700 Subject: [PATCH 7/8] tools: bpftool: show that `opcodes` or `file FILE` should be exclusive For the `bpftool prog dump { jited | xlated } ...` command, adding `opcodes` keyword (to request opcodes to be printed) will have no effect if `file FILE` (to write binary output to FILE) is provided. The manual page and the help message to be displayed in the terminal should reflect that, and indicate that these options should be mutually exclusive. Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/Documentation/bpftool-prog.rst | 8 ++++---- tools/bpf/bpftool/prog.c | 4 ++-- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst index 3968f0bd37dbe..69b3770370c8a 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -11,8 +11,8 @@ SYNOPSIS ======== | **bpftool** prog show [*PROG*] -| **bpftool** prog dump xlated *PROG* [file *FILE*] [opcodes] -| **bpftool** prog dump jited *PROG* [file *FILE*] [opcodes] +| **bpftool** prog dump xlated *PROG* [{file *FILE* | opcodes }] +| **bpftool** prog dump jited *PROG* [{file *FILE* | opcodes }] | **bpftool** prog pin *PROG* *FILE* | **bpftool** prog help | @@ -28,14 +28,14 @@ DESCRIPTION Output will start with program ID followed by program type and zero or more named attributes (depending on kernel version). - **bpftool prog dump xlated** *PROG* [**file** *FILE*] [**opcodes**] + **bpftool prog dump xlated** *PROG* [{ **file** *FILE* | **opcodes** }] Dump eBPF instructions of the program from the kernel. If *FILE* is specified image will be written to a file, otherwise it will be disassembled and printed to stdout. **opcodes** controls if raw opcodes will be printed. - **bpftool prog dump jited** *PROG* [**file** *FILE*] [**opcodes**] + **bpftool prog dump jited** *PROG* [{ **file** *FILE* | **opcodes** }] Dump jited image (host machine code) of the program. If *FILE* is specified image will be written to a file, otherwise it will be disassembled and printed to stdout. diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 57edbea2fbe82..7838206a455b7 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -469,8 +469,8 @@ static int do_help(int argc, char **argv) { fprintf(stderr, "Usage: %s %s show [PROG]\n" - " %s %s dump xlated PROG [file FILE] [opcodes]\n" - " %s %s dump jited PROG [file FILE] [opcodes]\n" + " %s %s dump xlated PROG [{ file FILE | opcodes }]\n" + " %s %s dump jited PROG [{ file FILE | opcodes }]\n" " %s %s pin PROG FILE\n" " %s %s help\n" "\n" From 821cfbb0dcfbb24506dc6958361ca2b80b928049 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Thu, 19 Oct 2017 15:46:26 -0700 Subject: [PATCH 8/8] tools: bpftool: add a command to display bpftool version This command can be used to print the version of the tool, which is in fact the version from Linux taken from usr/include/linux/version.h. Example usage: $ bpftool version bpftool v4.14.0 Signed-off-by: Quentin Monnet Signed-off-by: Jakub Kicinski Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/bpf/bpftool/Documentation/bpftool.rst | 2 ++ tools/bpf/bpftool/main.c | 14 +++++++++++++- 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/tools/bpf/bpftool/Documentation/bpftool.rst b/tools/bpf/bpftool/Documentation/bpftool.rst index f1df1893fb549..45ad8baf19159 100644 --- a/tools/bpf/bpftool/Documentation/bpftool.rst +++ b/tools/bpf/bpftool/Documentation/bpftool.rst @@ -14,6 +14,8 @@ SYNOPSIS **bpftool** batch file *FILE* + **bpftool** version + *OBJECT* := { **map** | **program** } *MAP-COMMANDS* := diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 8662199ee050f..814d19e1b53f5 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include #include @@ -62,13 +63,23 @@ static int do_help(int argc, char **argv) fprintf(stderr, "Usage: %s OBJECT { COMMAND | help }\n" " %s batch file FILE\n" + " %s version\n" "\n" " OBJECT := { prog | map }\n", - bin_name, bin_name); + bin_name, bin_name, bin_name); return 0; } +static int do_version(int argc, char **argv) +{ + printf("%s v%d.%d.%d\n", bin_name, + LINUX_VERSION_CODE >> 16, + LINUX_VERSION_CODE >> 8 & 0xf, + LINUX_VERSION_CODE & 0xf); + return 0; +} + int cmd_select(const struct cmd *cmds, int argc, char **argv, int (*help)(int argc, char **argv)) { @@ -128,6 +139,7 @@ static const struct cmd cmds[] = { { "batch", do_batch }, { "prog", do_prog }, { "map", do_map }, + { "version", do_version }, { 0 } };