diff options
Diffstat (limited to 'tools/perf/util/genelf.c')
| -rw-r--r-- | tools/perf/util/genelf.c | 117 |
1 files changed, 32 insertions, 85 deletions
diff --git a/tools/perf/util/genelf.c b/tools/perf/util/genelf.c index cdce7f173d00..14882def9704 100644 --- a/tools/perf/util/genelf.c +++ b/tools/perf/util/genelf.c @@ -12,14 +12,13 @@ #include <libelf.h> #include <string.h> #include <stdlib.h> -#include <unistd.h> #include <inttypes.h> -#include <fcntl.h> #include <err.h> #ifdef HAVE_LIBDW_SUPPORT #include <dwarf.h> #endif +#include "blake2s.h" #include "genelf.h" #include "../util/jitdump.h" #include <linux/compiler.h> @@ -28,25 +27,6 @@ #define NT_GNU_BUILD_ID 3 #endif -#define BUILD_ID_URANDOM /* different uuid for each run */ - -#ifdef HAVE_LIBCRYPTO_SUPPORT - -#define BUILD_ID_MD5 -#undef BUILD_ID_SHA /* does not seem to work well when linked with Java */ -#undef BUILD_ID_URANDOM /* different uuid for each run */ - -#ifdef BUILD_ID_SHA -#include <openssl/sha.h> -#endif - -#ifdef BUILD_ID_MD5 -#include <openssl/evp.h> -#include <openssl/md5.h> -#endif -#endif - - typedef struct { unsigned int namesz; /* Size of entry's owner string */ unsigned int descsz; /* Size of the note descriptor */ @@ -71,7 +51,7 @@ static char shd_string_table[] = { static struct buildid_note { Elf_Note desc; /* descsz: size of build-id, must be multiple of 4 */ char name[4]; /* GNU\0 */ - char build_id[20]; + u8 build_id[20]; } bnote; static Elf_Sym symtab[]={ @@ -92,65 +72,6 @@ static Elf_Sym symtab[]={ } }; -#ifdef BUILD_ID_URANDOM -static void -gen_build_id(struct buildid_note *note, - unsigned long load_addr __maybe_unused, - const void *code __maybe_unused, - size_t csize __maybe_unused) -{ - int fd; - size_t sz = sizeof(note->build_id); - ssize_t sret; - - fd = open("/dev/urandom", O_RDONLY); - if (fd == -1) - err(1, "cannot access /dev/urandom for buildid"); - - sret = read(fd, note->build_id, sz); - - close(fd); - - if (sret != (ssize_t)sz) - memset(note->build_id, 0, sz); -} -#endif - -#ifdef BUILD_ID_SHA -static void -gen_build_id(struct buildid_note *note, - unsigned long load_addr __maybe_unused, - const void *code, - size_t csize) -{ - if (sizeof(note->build_id) < SHA_DIGEST_LENGTH) - errx(1, "build_id too small for SHA1"); - - SHA1(code, csize, (unsigned char *)note->build_id); -} -#endif - -#ifdef BUILD_ID_MD5 -static void -gen_build_id(struct buildid_note *note, unsigned long load_addr, const void *code, size_t csize) -{ - EVP_MD_CTX *mdctx; - - if (sizeof(note->build_id) < 16) - errx(1, "build_id too small for MD5"); - - mdctx = EVP_MD_CTX_new(); - if (!mdctx) - errx(2, "failed to create EVP_MD_CTX"); - - EVP_DigestInit_ex(mdctx, EVP_md5(), NULL); - EVP_DigestUpdate(mdctx, &load_addr, sizeof(load_addr)); - EVP_DigestUpdate(mdctx, code, csize); - EVP_DigestFinal_ex(mdctx, (unsigned char *)note->build_id, NULL); - EVP_MD_CTX_free(mdctx); -} -#endif - static int jit_add_eh_frame_info(Elf *e, void* unwinding, uint64_t unwinding_header_size, uint64_t unwinding_size, uint64_t base_offset) @@ -231,15 +152,34 @@ jit_add_eh_frame_info(Elf *e, void* unwinding, uint64_t unwinding_header_size, return 0; } +enum { + TAG_CODE = 0, + TAG_SYMTAB = 1, + TAG_STRSYM = 2, +}; + +/* + * Update the hash using the given data, also prepending a (tag, len) prefix to + * ensure that distinct input tuples reliably result in distinct hashes. + */ +static void blake2s_update_tagged(struct blake2s_ctx *ctx, int tag, + const void *data, size_t len) +{ + u64 prefix = ((u64)tag << 56) | len; + + blake2s_update(ctx, (const u8 *)&prefix, sizeof(prefix)); + blake2s_update(ctx, data, len); +} + /* * fd: file descriptor open for writing for the output file - * load_addr: code load address (could be zero, just used for buildid) + * load_addr: code load address (could be zero) * sym: function name (for native code - used as the symbol) * code: the native code * csize: the code size in bytes */ int -jit_write_elf(int fd, uint64_t load_addr, const char *sym, +jit_write_elf(int fd, uint64_t load_addr __maybe_unused, const char *sym, const void *code, int csize, void *debug __maybe_unused, int nr_debug_entries __maybe_unused, void *unwinding, uint64_t unwinding_header_size, uint64_t unwinding_size) @@ -252,6 +192,7 @@ jit_write_elf(int fd, uint64_t load_addr, const char *sym, Elf_Shdr *shdr; uint64_t eh_frame_base_offset; char *strsym = NULL; + struct blake2s_ctx ctx; int symlen; int retval = -1; @@ -330,6 +271,9 @@ jit_write_elf(int fd, uint64_t load_addr, const char *sym, shdr->sh_flags = SHF_EXECINSTR | SHF_ALLOC; shdr->sh_entsize = 0; + blake2s_init(&ctx, sizeof(bnote.build_id)); + blake2s_update_tagged(&ctx, TAG_CODE, code, csize); + /* * Setup .eh_frame_hdr and .eh_frame */ @@ -413,6 +357,8 @@ jit_write_elf(int fd, uint64_t load_addr, const char *sym, shdr->sh_entsize = sizeof(Elf_Sym); shdr->sh_link = unwinding ? 6 : 4; /* index of .strtab section */ + blake2s_update_tagged(&ctx, TAG_SYMTAB, symtab, sizeof(symtab)); + /* * setup symbols string table * 2 = 1 for 0 in 1st entry, 1 for the 0 at end of symbol for 2nd entry @@ -455,6 +401,8 @@ jit_write_elf(int fd, uint64_t load_addr, const char *sym, shdr->sh_flags = 0; shdr->sh_entsize = 0; + blake2s_update_tagged(&ctx, TAG_STRSYM, strsym, symlen); + /* * setup build-id section */ @@ -473,7 +421,7 @@ jit_write_elf(int fd, uint64_t load_addr, const char *sym, /* * build-id generation */ - gen_build_id(&bnote, load_addr, code, csize); + blake2s_final(&ctx, bnote.build_id); bnote.desc.namesz = sizeof(bnote.name); /* must include 0 termination */ bnote.desc.descsz = sizeof(bnote.build_id); bnote.desc.type = NT_GNU_BUILD_ID; @@ -519,6 +467,5 @@ error: free(strsym); - return retval; } |