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-rw-r--r--lib/elf.c246
1 files changed, 246 insertions, 0 deletions
diff --git a/lib/elf.c b/lib/elf.c
new file mode 100644
index 0000000000..d074e4e0a7
--- /dev/null
+++ b/lib/elf.c
@@ -0,0 +1,246 @@
+// SPDX-License-Identifier: BSD-2-Clause
+/*
+ Copyright (c) 2001 William L. Pitts
+*/
+
+#include <common.h>
+#include <command.h>
+#include <cpu_func.h>
+#include <elf.h>
+#include <env.h>
+#include <net.h>
+#include <vxworks.h>
+#ifdef CONFIG_X86
+#include <vbe.h>
+#include <asm/e820.h>
+#include <linux/linkage.h>
+#endif
+
+/*
+ * A very simple ELF64 loader, assumes the image is valid, returns the
+ * entry point address.
+ *
+ * Note if U-Boot is 32-bit, the loader assumes the to segment's
+ * physical address and size is within the lower 32-bit address space.
+ */
+unsigned long load_elf64_image_phdr(unsigned long addr)
+{
+ Elf64_Ehdr *ehdr; /* Elf header structure pointer */
+ Elf64_Phdr *phdr; /* Program header structure pointer */
+ int i;
+
+ ehdr = (Elf64_Ehdr *)addr;
+ phdr = (Elf64_Phdr *)(addr + (ulong)ehdr->e_phoff);
+
+ /* Load each program header */
+ for (i = 0; i < ehdr->e_phnum; ++i) {
+ void *dst = (void *)(ulong)phdr->p_paddr;
+ void *src = (void *)addr + phdr->p_offset;
+
+ debug("Loading phdr %i to 0x%p (%lu bytes)\n",
+ i, dst, (ulong)phdr->p_filesz);
+ if (phdr->p_filesz)
+ memcpy(dst, src, phdr->p_filesz);
+ if (phdr->p_filesz != phdr->p_memsz)
+ memset(dst + phdr->p_filesz, 0x00,
+ phdr->p_memsz - phdr->p_filesz);
+ flush_cache(rounddown((unsigned long)dst, ARCH_DMA_MINALIGN),
+ roundup(phdr->p_memsz, ARCH_DMA_MINALIGN));
+ ++phdr;
+ }
+
+ if (ehdr->e_machine == EM_PPC64 && (ehdr->e_flags &
+ EF_PPC64_ELFV1_ABI)) {
+ /*
+ * For the 64-bit PowerPC ELF V1 ABI, e_entry is a function
+ * descriptor pointer with the first double word being the
+ * address of the entry point of the function.
+ */
+ uintptr_t addr = ehdr->e_entry;
+
+ return *(Elf64_Addr *)addr;
+ }
+
+ return ehdr->e_entry;
+}
+
+unsigned long load_elf64_image_shdr(unsigned long addr)
+{
+ Elf64_Ehdr *ehdr; /* Elf header structure pointer */
+ Elf64_Shdr *shdr; /* Section header structure pointer */
+ unsigned char *strtab = 0; /* String table pointer */
+ unsigned char *image; /* Binary image pointer */
+ int i; /* Loop counter */
+
+ ehdr = (Elf64_Ehdr *)addr;
+
+ /* Find the section header string table for output info */
+ shdr = (Elf64_Shdr *)(addr + (ulong)ehdr->e_shoff +
+ (ehdr->e_shstrndx * sizeof(Elf64_Shdr)));
+
+ if (shdr->sh_type == SHT_STRTAB)
+ strtab = (unsigned char *)(addr + (ulong)shdr->sh_offset);
+
+ /* Load each appropriate section */
+ for (i = 0; i < ehdr->e_shnum; ++i) {
+ shdr = (Elf64_Shdr *)(addr + (ulong)ehdr->e_shoff +
+ (i * sizeof(Elf64_Shdr)));
+
+ if (!(shdr->sh_flags & SHF_ALLOC) ||
+ shdr->sh_addr == 0 || shdr->sh_size == 0) {
+ continue;
+ }
+
+ if (strtab) {
+ debug("%sing %s @ 0x%08lx (%ld bytes)\n",
+ (shdr->sh_type == SHT_NOBITS) ? "Clear" : "Load",
+ &strtab[shdr->sh_name],
+ (unsigned long)shdr->sh_addr,
+ (long)shdr->sh_size);
+ }
+
+ if (shdr->sh_type == SHT_NOBITS) {
+ memset((void *)(uintptr_t)shdr->sh_addr, 0,
+ shdr->sh_size);
+ } else {
+ image = (unsigned char *)addr + (ulong)shdr->sh_offset;
+ memcpy((void *)(uintptr_t)shdr->sh_addr,
+ (const void *)image, shdr->sh_size);
+ }
+ flush_cache(rounddown(shdr->sh_addr, ARCH_DMA_MINALIGN),
+ roundup((shdr->sh_addr + shdr->sh_size),
+ ARCH_DMA_MINALIGN) -
+ rounddown(shdr->sh_addr, ARCH_DMA_MINALIGN));
+ }
+
+ if (ehdr->e_machine == EM_PPC64 && (ehdr->e_flags &
+ EF_PPC64_ELFV1_ABI)) {
+ /*
+ * For the 64-bit PowerPC ELF V1 ABI, e_entry is a function
+ * descriptor pointer with the first double word being the
+ * address of the entry point of the function.
+ */
+ uintptr_t addr = ehdr->e_entry;
+
+ return *(Elf64_Addr *)addr;
+ }
+
+ return ehdr->e_entry;
+}
+
+/*
+ * A very simple ELF loader, assumes the image is valid, returns the
+ * entry point address.
+ *
+ * The loader firstly reads the EFI class to see if it's a 64-bit image.
+ * If yes, call the ELF64 loader. Otherwise continue with the ELF32 loader.
+ */
+unsigned long load_elf_image_phdr(unsigned long addr)
+{
+ Elf32_Ehdr *ehdr; /* Elf header structure pointer */
+ Elf32_Phdr *phdr; /* Program header structure pointer */
+ int i;
+
+ ehdr = (Elf32_Ehdr *)addr;
+ if (ehdr->e_ident[EI_CLASS] == ELFCLASS64)
+ return load_elf64_image_phdr(addr);
+
+ phdr = (Elf32_Phdr *)(addr + ehdr->e_phoff);
+
+ /* Load each program header */
+ for (i = 0; i < ehdr->e_phnum; ++i) {
+ void *dst = (void *)(uintptr_t)phdr->p_paddr;
+ void *src = (void *)addr + phdr->p_offset;
+
+ debug("Loading phdr %i to 0x%p (%i bytes)\n",
+ i, dst, phdr->p_filesz);
+ if (phdr->p_filesz)
+ memcpy(dst, src, phdr->p_filesz);
+ if (phdr->p_filesz != phdr->p_memsz)
+ memset(dst + phdr->p_filesz, 0x00,
+ phdr->p_memsz - phdr->p_filesz);
+ flush_cache(rounddown((unsigned long)dst, ARCH_DMA_MINALIGN),
+ roundup(phdr->p_memsz, ARCH_DMA_MINALIGN));
+ ++phdr;
+ }
+
+ return ehdr->e_entry;
+}
+
+unsigned long load_elf_image_shdr(unsigned long addr)
+{
+ Elf32_Ehdr *ehdr; /* Elf header structure pointer */
+ Elf32_Shdr *shdr; /* Section header structure pointer */
+ unsigned char *strtab = 0; /* String table pointer */
+ unsigned char *image; /* Binary image pointer */
+ int i; /* Loop counter */
+
+ ehdr = (Elf32_Ehdr *)addr;
+ if (ehdr->e_ident[EI_CLASS] == ELFCLASS64)
+ return load_elf64_image_shdr(addr);
+
+ /* Find the section header string table for output info */
+ shdr = (Elf32_Shdr *)(addr + ehdr->e_shoff +
+ (ehdr->e_shstrndx * sizeof(Elf32_Shdr)));
+
+ if (shdr->sh_type == SHT_STRTAB)
+ strtab = (unsigned char *)(addr + shdr->sh_offset);
+
+ /* Load each appropriate section */
+ for (i = 0; i < ehdr->e_shnum; ++i) {
+ shdr = (Elf32_Shdr *)(addr + ehdr->e_shoff +
+ (i * sizeof(Elf32_Shdr)));
+
+ if (!(shdr->sh_flags & SHF_ALLOC) ||
+ shdr->sh_addr == 0 || shdr->sh_size == 0) {
+ continue;
+ }
+
+ if (strtab) {
+ debug("%sing %s @ 0x%08lx (%ld bytes)\n",
+ (shdr->sh_type == SHT_NOBITS) ? "Clear" : "Load",
+ &strtab[shdr->sh_name],
+ (unsigned long)shdr->sh_addr,
+ (long)shdr->sh_size);
+ }
+
+ if (shdr->sh_type == SHT_NOBITS) {
+ memset((void *)(uintptr_t)shdr->sh_addr, 0,
+ shdr->sh_size);
+ } else {
+ image = (unsigned char *)addr + shdr->sh_offset;
+ memcpy((void *)(uintptr_t)shdr->sh_addr,
+ (const void *)image, shdr->sh_size);
+ }
+ flush_cache(rounddown(shdr->sh_addr, ARCH_DMA_MINALIGN),
+ roundup((shdr->sh_addr + shdr->sh_size),
+ ARCH_DMA_MINALIGN) -
+ rounddown(shdr->sh_addr, ARCH_DMA_MINALIGN));
+ }
+
+ return ehdr->e_entry;
+}
+
+/*
+ * Determine if a valid ELF image exists at the given memory location.
+ * First look at the ELF header magic field, then make sure that it is
+ * executable.
+ */
+int valid_elf_image(unsigned long addr)
+{
+ Elf32_Ehdr *ehdr; /* Elf header structure pointer */
+
+ ehdr = (Elf32_Ehdr *)addr;
+
+ if (!IS_ELF(*ehdr)) {
+ printf("## No elf image at address 0x%08lx\n", addr);
+ return 0;
+ }
+
+ if (ehdr->e_type != ET_EXEC) {
+ printf("## Not a 32-bit elf image at address 0x%08lx\n", addr);
+ return 0;
+ }
+
+ return 1;
+}
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