diff options
| -rw-r--r-- | bpf_parser.y | 6 | ||||
| -rw-r--r-- | bpfc.8 | 4 | ||||
| -rw-r--r-- | bpfc.c | 16 |
3 files changed, 20 insertions, 6 deletions
diff --git a/bpf_parser.y b/bpf_parser.y index 7331cc5..2c566a1 100644 --- a/bpf_parser.y +++ b/bpf_parser.y @@ -28,7 +28,7 @@ #include "cpp.h" int compile_filter(char *file, int verbose, int bypass, int format, - bool invoke_cpp); + bool invoke_cpp, char **cpp_argv); static int curr_instr = 0; @@ -735,7 +735,7 @@ static void pretty_printer(const struct sock_fprog *prog, int format) } int compile_filter(char *file, int verbose, int bypass, int format, - bool invoke_cpp) + bool invoke_cpp, char **cpp_argv) { int i; struct sock_fprog res; @@ -745,7 +745,7 @@ int compile_filter(char *file, int verbose, int bypass, int format, memset(tmp_file, 0, sizeof(tmp_file)); if (invoke_cpp) { - ret = cpp_exec(file, tmp_file, sizeof(tmp_file), NULL); + ret = cpp_exec(file, tmp_file, sizeof(tmp_file), cpp_argv); if (ret) { fprintf(stderr, "Failed to invoke C preprocessor!\n"); goto exit; @@ -65,6 +65,10 @@ Pass the bpf program through the C preprocessor before reading it in bpfc. This allows #define and #include directives (e.g. to include definitions from system headers) to be used in the bpf program. .PP +.SS -D <name>=<definition>, --define <name>=<definition> +Add macro definition for the C preprocessor to use it within bpf file. This +option is used in combination with the -p,--cpp option. +.PP .SS -f <format>, --format <format> Specify a different output format than the default that is netsniff-ng compatible. The <format> specifier can be: C, netsniff-ng, xt_bpf, tcpdump. @@ -17,12 +17,14 @@ #include "die.h" #include "bpf.h" #include "config.h" +#include "str.h" -static const char *short_options = "vhi:Vdbf:p"; +static const char *short_options = "vhi:Vdbf:pD:"; static const struct option long_options[] = { {"input", required_argument, NULL, 'i'}, {"format", required_argument, NULL, 'f'}, {"cpp", no_argument, NULL, 'p'}, + {"define", required_argument, NULL, 'D'}, {"verbose", no_argument, NULL, 'V'}, {"bypass", no_argument, NULL, 'b'}, {"dump", no_argument, NULL, 'd'}, @@ -39,7 +41,7 @@ static const char *copyright = "Please report bugs to <netsniff-ng@googlegroups. "There is NO WARRANTY, to the extent permitted by law."; extern int compile_filter(char *file, int verbose, int bypass, int format, - bool invoke_cpp); + bool invoke_cpp, char **cpp_argv); static void __noreturn help(void) { @@ -49,6 +51,7 @@ static void __noreturn help(void) "Options:\n" " -i|--input <program/-> Berkeley Packet Filter file/stdin\n" " -p|--cpp Run bpf program through C preprocessor\n" + " -D|--define Add macro/define for C preprocessor\n" " -f|--format <format> Output format: C|netsniff-ng|xt_bpf|tcpdump\n" " -b|--bypass Bypass filter validation (e.g. for bug testing)\n" " -V|--verbose Be more verbose\n" @@ -81,6 +84,8 @@ int main(int argc, char **argv) { int ret, verbose = 0, c, opt_index, bypass = 0, format = 0; bool invoke_cpp = false; + char **cpp_argv = NULL; + size_t cpp_argc = 0; char *file = NULL; setfsuid(getuid()); @@ -104,6 +109,10 @@ int main(int argc, char **argv) case 'p': invoke_cpp = true; break; + case 'D': + cpp_argv = argv_insert(cpp_argv, &cpp_argc, "-D"); + cpp_argv = argv_insert(cpp_argv, &cpp_argc, optarg); + break; case 'f': if (!strncmp(optarg, "C", 1) || !strncmp(optarg, "netsniff-ng", 11)) @@ -146,8 +155,9 @@ int main(int argc, char **argv) if (!file) panic("No Berkeley Packet Filter program specified!\n"); - ret = compile_filter(file, verbose, bypass, format, invoke_cpp); + ret = compile_filter(file, verbose, bypass, format, invoke_cpp, cpp_argv); + argv_free(cpp_argv); xfree(file); return ret; } |