From a7d22ca2a483d6c69c0791954447464297315ffa Mon Sep 17 00:00:00 2001 From: Paul Chaignon Date: Fri, 13 Dec 2019 20:10:17 +0100 Subject: [PATCH] bpftool: Match programs by name When working with frequently modified BPF programs, both the ID and the tag may change. bpftool currently doesn't provide a "stable" way to match such programs. This patch implements lookup by name for programs. The show and dump commands will return all programs with the given name, whereas other commands will error out if several programs have the same name. Signed-off-by: Paul Chaignon Signed-off-by: Alexei Starovoitov Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/b5fc1a5dcfaeb5f16fc80295cdaa606dd2d91534.1576263640.git.paul.chaignon@gmail.com --- .../bpf/bpftool/Documentation/bpftool-map.rst | 2 +- .../bpftool/Documentation/bpftool-prog.rst | 12 +++++----- tools/bpf/bpftool/bash-completion/bpftool | 22 ++++++++++++++----- tools/bpf/bpftool/main.h | 2 +- tools/bpf/bpftool/prog.c | 22 +++++++++++++++---- 5 files changed, 42 insertions(+), 18 deletions(-) diff --git a/tools/bpf/bpftool/Documentation/bpftool-map.rst b/tools/bpf/bpftool/Documentation/bpftool-map.rst index 1c0f7146aab0..90d848b5b7d3 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-map.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-map.rst @@ -41,7 +41,7 @@ MAP COMMANDS | | *MAP* := { **id** *MAP_ID* | **pinned** *FILE* } | *DATA* := { [**hex**] *BYTES* } -| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* } +| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* | **name** *PROG_NAME* } | *VALUE* := { *DATA* | *MAP* | *PROG* } | *UPDATE_FLAGS* := { **any** | **exist** | **noexist** } | *TYPE* := { **hash** | **array** | **prog_array** | **perf_event_array** | **percpu_hash** diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst index d377d0cb7923..64ddf8a4c518 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -33,7 +33,7 @@ PROG COMMANDS | **bpftool** **prog help** | | *MAP* := { **id** *MAP_ID* | **pinned** *FILE* } -| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* } +| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* | **name** *PROG_NAME* } | *TYPE* := { | **socket** | **kprobe** | **kretprobe** | **classifier** | **action** | | **tracepoint** | **raw_tracepoint** | **xdp** | **perf_event** | **cgroup/skb** | @@ -55,8 +55,8 @@ DESCRIPTION Show information about loaded programs. If *PROG* is specified show information only about given programs, otherwise list all programs currently loaded on the system. - In case of **tag**, *PROG* may match several programs which - will all be shown. + In case of **tag** or **name**, *PROG* may match several + programs which will all be shown. Output will start with program ID followed by program type and zero or more named attributes (depending on kernel version). @@ -75,9 +75,9 @@ DESCRIPTION output in human-readable format. In this case, **opcodes** controls if raw opcodes should be printed as well. - In case of **tag**, *PROG* may match several programs which - will all be dumped. However, if **file** or **visual** is - specified, *PROG* must match a single program. + In case of **tag** or **name**, *PROG* may match several + programs which will all be dumped. However, if **file** or + **visual** is specified, *PROG* must match a single program. If **file** is specified, the binary image will instead be written to *FILE*. diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index 70493a6da206..05b5be4a6ef9 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -71,6 +71,12 @@ _bpftool_get_prog_tags() command sed -n 's/.*"tag": "\(.*\)",$/\1/p' )" -- "$cur" ) ) } +_bpftool_get_prog_names() +{ + COMPREPLY+=( $( compgen -W "$( bpftool -jp prog 2>&1 | \ + command sed -n 's/.*"name": "\(.*\)",$/\1/p' )" -- "$cur" ) ) +} + _bpftool_get_btf_ids() { COMPREPLY+=( $( compgen -W "$( bpftool -jp btf 2>&1 | \ @@ -201,6 +207,10 @@ _bpftool() _bpftool_get_prog_tags return 0 ;; + name) + _bpftool_get_prog_names + return 0 + ;; dev) _sysfs_get_netdevs return 0 @@ -263,7 +273,7 @@ _bpftool() ;; esac - local PROG_TYPE='id pinned tag' + local PROG_TYPE='id pinned tag name' local MAP_TYPE='id pinned' case $command in show|list) @@ -559,7 +569,7 @@ _bpftool() return 0 ;; prog_array) - local PROG_TYPE='id pinned tag' + local PROG_TYPE='id pinned tag name' COMPREPLY+=( $( compgen -W "$PROG_TYPE" \ -- "$cur" ) ) return 0 @@ -644,7 +654,7 @@ _bpftool() esac ;; btf) - local PROG_TYPE='id pinned tag' + local PROG_TYPE='id pinned tag name' local MAP_TYPE='id pinned' case $command in dump) @@ -735,7 +745,7 @@ _bpftool() connect6 sendmsg4 sendmsg6 recvmsg4 recvmsg6 sysctl \ getsockopt setsockopt' local ATTACH_FLAGS='multi override' - local PROG_TYPE='id pinned tag' + local PROG_TYPE='id pinned tag name' case $prev in $command) _filedir @@ -760,7 +770,7 @@ _bpftool() elif [[ "$command" == "attach" ]]; then # We have an attach type on the command line, # but it is not the previous word, or - # "id|pinned|tag" (we already checked for + # "id|pinned|tag|name" (we already checked for # that). This should only leave the case when # we need attach flags for "attach" commamnd. _bpftool_one_of_list "$ATTACH_FLAGS" @@ -786,7 +796,7 @@ _bpftool() esac ;; net) - local PROG_TYPE='id pinned tag' + local PROG_TYPE='id pinned tag name' local ATTACH_TYPES='xdp xdpgeneric xdpdrv xdpoffload' case $command in show|list) diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 2899095f8254..a7ead7bb9447 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -42,7 +42,7 @@ #define BPF_TAG_FMT "%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx" #define HELP_SPEC_PROGRAM \ - "PROG := { id PROG_ID | pinned FILE | tag PROG_TAG }" + "PROG := { id PROG_ID | pinned FILE | tag PROG_TAG | name PROG_NAME }" #define HELP_SPEC_OPTIONS \ "OPTIONS := { {-j|--json} [{-p|--pretty}] | {-f|--bpffs} |\n" \ "\t {-m|--mapcompat} | {-n|--nomount} }" diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 37948c47aabd..2221bae037f1 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -82,7 +82,7 @@ static void print_boot_time(__u64 nsecs, char *buf, unsigned int size) strftime(buf, size, "%FT%T%z", &load_tm); } -static int prog_fd_by_tag(unsigned char *tag, int **fds) +static int prog_fd_by_nametag(void *nametag, int **fds, bool tag) { unsigned int id = 0; int fd, nb_fds = 0; @@ -116,7 +116,8 @@ static int prog_fd_by_tag(unsigned char *tag, int **fds) goto err_close_fd; } - if (memcmp(tag, info.tag, BPF_TAG_SIZE)) { + if ((tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) || + (!tag && strncmp(nametag, info.name, BPF_OBJ_NAME_LEN))) { close(fd); continue; } @@ -174,7 +175,20 @@ static int prog_parse_fds(int *argc, char ***argv, int **fds) } NEXT_ARGP(); - return prog_fd_by_tag(tag, fds); + return prog_fd_by_nametag(tag, fds, true); + } else if (is_prefix(**argv, "name")) { + char *name; + + NEXT_ARGP(); + + name = **argv; + if (strlen(name) > BPF_OBJ_NAME_LEN - 1) { + p_err("can't parse name"); + return -1; + } + NEXT_ARGP(); + + return prog_fd_by_nametag(name, fds, false); } else if (is_prefix(**argv, "pinned")) { char *path; @@ -189,7 +203,7 @@ static int prog_parse_fds(int *argc, char ***argv, int **fds) return 1; } - p_err("expected 'id', 'tag' or 'pinned', got: '%s'?", **argv); + p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv); return -1; } -- 2.30.2