diff options
Diffstat (limited to 'nuttx/binfmt/libelf/libelf_init.c')
-rw-r--r-- | nuttx/binfmt/libelf/libelf_init.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/nuttx/binfmt/libelf/libelf_init.c b/nuttx/binfmt/libelf/libelf_init.c new file mode 100644 index 000000000..fa4b7983c --- /dev/null +++ b/nuttx/binfmt/libelf/libelf_init.c @@ -0,0 +1,202 @@ +/**************************************************************************** + * binfmt/libelf/libelf_init.c + * + * Copyright (C) 2012 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/stat.h> + +#include <stdint.h> +#include <string.h> +#include <fcntl.h> +#include <elf32.h> +#include <debug.h> +#include <errno.h> + +#include <nuttx/binfmt/elf.h> + +#include "libelf.h" + +/**************************************************************************** + * Pre-Processor Definitions + ****************************************************************************/ + +/* CONFIG_DEBUG, CONFIG_DEBUG_VERBOSE, and CONFIG_DEBUG_BINFMT have to be + * defined or CONFIG_ELF_DUMPBUFFER does nothing. + */ + +#if !defined(CONFIG_DEBUG_VERBOSE) || !defined (CONFIG_DEBUG_BINFMT) +# undef CONFIG_ELF_DUMPBUFFER +#endif + +#ifdef CONFIG_ELF_DUMPBUFFER +# define elf_dumpbuffer(m,b,n) bvdbgdumpbuffer(m,b,n) +#else +# define elf_dumpbuffer(m,b,n) +#endif + +/**************************************************************************** + * Private Constant Data + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: elf_filelen + * + * Description: + * Get the size of the ELF file + * + * Returned Value: + * 0 (OK) is returned on success and a negated errno is returned on + * failure. + * + ****************************************************************************/ + +static inline int elf_filelen(FAR struct elf_loadinfo_s *loadinfo, + FAR const char *filename) +{ + struct stat buf; + int ret; + + /* Get the file stats */ + + ret = stat(filename, &buf); + if (ret < 0) + { + int errval = errno; + bdbg("Failed to fstat file: %d\n", errval); + return -errval; + } + + /* Verify that it is a regular file */ + + if (!S_ISREG(buf.st_mode)) + { + bdbg("Not a regular file. mode: %d\n", buf.st_mode); + return -ENOENT; + } + + /* TODO: Verify that the file is readable. Not really important because + * we will detect this when we try to open the file read-only. + */ + + /* Return the size of the file in the loadinfo structure */ + + loadinfo->filelen = buf.st_size; + return OK; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: elf_init + * + * Description: + * This function is called to configure the library to process an ELF + * program binary. + * + * Returned Value: + * 0 (OK) is returned on success and a negated errno is returned on + * failure. + * + ****************************************************************************/ + +int elf_init(FAR const char *filename, FAR struct elf_loadinfo_s *loadinfo) +{ + int ret; + + bvdbg("filename: %s loadinfo: %p\n", filename, loadinfo); + + /* Clear the load info structure */ + + memset(loadinfo, 0, sizeof(struct elf_loadinfo_s)); + + /* Get the length of the file. */ + + ret = elf_filelen(loadinfo, filename); + if (ret < 0) + { + bdbg("elf_filelen failed: %d\n", ret); + return ret; + } + + /* Open the binary file for reading (only) */ + + loadinfo->filfd = open(filename, O_RDONLY); + if (loadinfo->filfd < 0) + { + int errval = errno; + bdbg("Failed to open ELF binary %s: %d\n", filename, errval); + return -errval; + } + + /* Read the ELF ehdr from offset 0 */ + + ret = elf_read(loadinfo, (FAR uint8_t*)&loadinfo->ehdr, sizeof(Elf32_Ehdr), 0); + if (ret < 0) + { + bdbg("Failed to read ELF header: %d\n", ret); + return ret; + } + + elf_dumpbuffer("ELF header", (FAR const uint8_t*)&loadinfo->ehdr, sizeof(Elf32_Ehdr)); + + /* Verify the ELF header */ + + ret = elf_verifyheader(&loadinfo->ehdr); + if (ret <0) + { + /* This may not be an error because we will be called to attempt loading + * EVERY binary. If elf_verifyheader() does not recognize the ELF header, + * it will -ENOEXEC whcih simply informs the system that the file is not an + * ELF file. elf_verifyheader() will return other errors if the ELF header + * is not correctly formed. + */ + + bdbg("Bad ELF header: %d\n", ret); + return ret; + } + + return OK; +} + |