From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40996) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1abo7V-0005CY-S1 for qemu-devel@nongnu.org; Fri, 04 Mar 2016 06:42:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1abo7U-0001B6-Ts for qemu-devel@nongnu.org; Fri, 04 Mar 2016 06:42:09 -0500 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:56106) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1abo7U-0001At-Nf for qemu-devel@nongnu.org; Fri, 04 Mar 2016 06:42:08 -0500 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.84) (envelope-from ) id 1abo7U-0001zv-7d for qemu-devel@nongnu.org; Fri, 04 Mar 2016 11:42:08 +0000 From: Peter Maydell Date: Fri, 4 Mar 2016 11:41:48 +0000 Message-Id: <1457091713-10138-26-git-send-email-peter.maydell@linaro.org> In-Reply-To: <1457091713-10138-1-git-send-email-peter.maydell@linaro.org> References: <1457091713-10138-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PULL 25/30] loader: add API to load elf header List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org From: Peter Crosthwaite Add an API to load an elf header header from a file. Populates a buffer with the header contents, as well as a boolean for whether the elf is 64b or not. Both arguments are optional. Signed-off-by: Peter Crosthwaite Reviewed-by: Peter Maydell [PMM: Fix typo in comment] Signed-off-by: Peter Maydell --- hw/core/loader.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++++ include/hw/loader.h | 13 +++++++++++++ 2 files changed, 68 insertions(+) diff --git a/hw/core/loader.c b/hw/core/loader.c index 260b3d6..125aa05 100644 --- a/hw/core/loader.c +++ b/hw/core/loader.c @@ -354,6 +354,61 @@ const char *load_elf_strerror(int error) } } +void load_elf_hdr(const char *filename, void *hdr, bool *is64, Error **errp) +{ + int fd; + uint8_t e_ident_local[EI_NIDENT]; + uint8_t *e_ident; + size_t hdr_size, off; + bool is64l; + + if (!hdr) { + hdr = e_ident_local; + } + e_ident = hdr; + + fd = open(filename, O_RDONLY | O_BINARY); + if (fd < 0) { + error_setg_errno(errp, errno, "Failed to open file: %s", filename); + return; + } + if (read(fd, hdr, EI_NIDENT) != EI_NIDENT) { + error_setg_errno(errp, errno, "Failed to read file: %s", filename); + goto fail; + } + if (e_ident[0] != ELFMAG0 || + e_ident[1] != ELFMAG1 || + e_ident[2] != ELFMAG2 || + e_ident[3] != ELFMAG3) { + error_setg(errp, "Bad ELF magic"); + goto fail; + } + + is64l = e_ident[EI_CLASS] == ELFCLASS64; + hdr_size = is64l ? sizeof(Elf64_Ehdr) : sizeof(Elf32_Ehdr); + if (is64) { + *is64 = is64l; + } + + off = EI_NIDENT; + while (hdr != e_ident_local && off < hdr_size) { + size_t br = read(fd, hdr + off, hdr_size - off); + switch (br) { + case 0: + error_setg(errp, "File too short: %s", filename); + goto fail; + case -1: + error_setg_errno(errp, errno, "Failed to read file: %s", + filename); + goto fail; + } + off += br; + } + +fail: + close(fd); +} + /* return < 0 if error, otherwise the number of bytes loaded in memory */ int load_elf(const char *filename, uint64_t (*translate_fn)(void *, uint64_t), void *translate_opaque, uint64_t *pentry, uint64_t *lowaddr, diff --git a/include/hw/loader.h b/include/hw/loader.h index 09c3764..358da55 100644 --- a/include/hw/loader.h +++ b/include/hw/loader.h @@ -48,6 +48,19 @@ int load_elf(const char *filename, uint64_t (*translate_fn)(void *, uint64_t), void *translate_opaque, uint64_t *pentry, uint64_t *lowaddr, uint64_t *highaddr, int big_endian, int elf_machine, int clear_lsb); + +/** load_elf_hdr: + * @filename: Path of ELF file + * @hdr: Buffer to populate with header data. Header data will not be + * filled if set to NULL. + * @is64: Set to true if the ELF is 64bit. Ignored if set to NULL + * @errp: Populated with an error in failure cases + * + * Inspect an ELF file's header. Read its full header contents into a + * buffer and/or determine if the ELF is 64bit. + */ +void load_elf_hdr(const char *filename, void *hdr, bool *is64, Error **errp); + int load_aout(const char *filename, hwaddr addr, int max_sz, int bswap_needed, hwaddr target_page_size); int load_uimage(const char *filename, hwaddr *ep, -- 1.9.1