diff --git a/misc/efi-stub/Makefile b/misc/efi-stub/Makefile index 8f7e136cd..fe5c674e2 100644 --- a/misc/efi-stub/Makefile +++ b/misc/efi-stub/Makefile @@ -32,7 +32,7 @@ HV_OBJDIR:=build HV_SRC:=../../hypervisor -C_SRCS = boot.c pe.c malloc.c multiboot.c +C_SRCS = boot.c pe.c malloc.c multiboot.c elf32.c ACRN_OBJS := $(patsubst %.c,$(EFI_OBJDIR)/%.o,$(C_SRCS)) INCLUDE_PATH += $(INCDIR)/efi INCLUDE_PATH += $(HV_SRC)/include/public diff --git a/misc/efi-stub/elf32.c b/misc/efi-stub/elf32.c new file mode 100644 index 000000000..b9f721f87 --- /dev/null +++ b/misc/efi-stub/elf32.c @@ -0,0 +1,157 @@ +/* + * Copyright (c) 2021, Intel Corporation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * 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. + * * Neither the name of Intel Corporation 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. + */ + +#include +#include +#include "stdlib.h" +#include "boot.h" + +#define MAX(a, b) (((a) > (b)) ? (a) : (b)) +#define MIN(a, b) (((a) < (b)) ? (a) : (b)) + + +/** + * @brief Load elf pointed by ehdr, linked at link_addr, to load_addr. + * + * @param[in] ehdr A pointer to target ELF header. + * @param[in] load_addr The address to which the image will be loaded. + * @param[in] link_addr The address to which the image was linked. + * + * @return 0 on success, -1 on error. + */ +int elf_load(Elf32_Ehdr *ehdr, uint64_t load_addr, uint64_t link_addr) +{ + int i; + uint64_t addr; + Elf32_Phdr *phdr; + Elf32_Phdr *pbase = (Elf32_Phdr *)((char *)ehdr + ehdr->e_phoff); + + for (i = 0; i < ehdr->e_phnum; i++) { + phdr = (Elf32_Phdr *)((char *)pbase + i * ehdr->e_phentsize); + if ((phdr->p_type != PT_LOAD) || (phdr->p_memsz == 0) || (phdr->p_offset == 0)) { + continue; + } + + if (phdr->p_filesz > phdr->p_memsz) { + return -1; + } + + addr = (uint64_t)(load_addr + (phdr->p_paddr - link_addr)); + memcpy((char *)addr, (const char *)((char *)ehdr + phdr->p_offset), phdr->p_filesz); + + if (phdr->p_memsz > phdr->p_filesz) { + addr = (uint64_t)(load_addr + (phdr->p_paddr - link_addr + phdr->p_filesz)); + (void)memset((void *)addr, 0x0, (phdr->p_memsz - phdr->p_filesz)); + } + } + + return 0; +} + +/** + * @brief Calculate link address range of the elf image. + * + * @param[in] ehdr A pointer to target ELF header. + * @param[out] link_addr_low The lowest link address of all loadable section in ELF. + * @param[out] link_addr_high The highest reachable link address (link address plus memory size of that section) of all + * loadable section in ELF. + * + * @return 0 on success, -1 on error. + */ +int elf_calc_link_addr_range(Elf32_Ehdr *ehdr, uint64_t *link_addr_low, uint64_t *link_addr_high) +{ + Elf32_Phdr *phdr; + Elf32_Phdr *pbase = (Elf32_Phdr *)((char *)ehdr + ehdr->e_phoff); + + int i; + uint64_t ram_low = ~0; + uint64_t ram_high = 0; + + for (i = 0; i < ehdr->e_phnum; i++) { + phdr = (Elf32_Phdr *)((char *)pbase + i * ehdr->e_phentsize); + if (phdr->p_type != PT_LOAD) + continue; + + ram_low = MIN(ram_low, phdr->p_paddr); + ram_high = MAX(ram_high, ALIGN_UP(phdr->p_paddr + phdr->p_memsz, phdr->p_align)); + } + + *link_addr_low = ram_low; + *link_addr_high = ram_high; + + return 0; +} + +/** + * @brief Get entry point of ELF image. + * + * @param[in] ehdr A pointer to target ELF header. + * + * @return Entry point address of ELF image. + */ +uint32_t elf_get_entry(Elf32_Ehdr *ehdr) +{ + return ehdr->e_entry; +} + +/** + * @brief Validate ELF header. + * + * @param[in] ehdr A pointer to target ELF header. + * + * @return 0 on success (valid elf), -1 on error. + */ +int validate_elf_header(Elf32_Ehdr *ehdr) +{ + if (ehdr->e_ident[EI_MAG0] != ELFMAG0 || + ehdr->e_ident[EI_MAG1] != ELFMAG1 || + ehdr->e_ident[EI_MAG2] != ELFMAG2 || + ehdr->e_ident[EI_MAG3] != ELFMAG3 || + ehdr->e_ident[EI_DATA] != ELFDATA2LSB) { + Print(L"Image is not a valid arch-independent ELF\n"); + return -1; + } + + if (ehdr->e_ident[EI_CLASS] != ELFCLASS32 || + ehdr->e_machine != EM_386 || + ehdr->e_version != EV_CURRENT) { + Print(L"Image is not a valid arch-dependent ELF\n"); + return -1; + } + + if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) { + Print(L"This ELF is not of the right type\n"); + return -1; + } + + return 0; +} diff --git a/misc/efi-stub/elf32.h b/misc/efi-stub/elf32.h new file mode 100644 index 000000000..1d5087116 --- /dev/null +++ b/misc/efi-stub/elf32.h @@ -0,0 +1,44 @@ +/* + * Copyright (c) 2021, Intel Corporation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * 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. + * * Neither the name of Intel Corporation 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. + */ + +#ifndef _ACRNELF_H +#define _ACRNELF_H + +#include +#include + +int elf_load(Elf32_Ehdr *ehdr, uint64_t load_addr, uint64_t link_addr); +int elf_calc_link_addr_range(Elf32_Ehdr *ehdr, uint64_t *link_addr_low, uint64_t *link_addr_high); +int validate_elf_header(Elf32_Ehdr *ehdr); +uint32_t elf_get_entry(Elf32_Ehdr *ehdr); + +#endif