diff options
Diffstat (limited to 'src/boot/elfboot.c')
-rw-r--r-- | src/boot/elfboot.c | 687 |
1 files changed, 0 insertions, 687 deletions
diff --git a/src/boot/elfboot.c b/src/boot/elfboot.c deleted file mode 100644 index 958112d669..0000000000 --- a/src/boot/elfboot.c +++ /dev/null @@ -1,687 +0,0 @@ -/* - * This file is part of the coreboot project. - * - * Copyright (C) 2003 Eric W. Biederman <ebiederm@xmission.com> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; version 2 of the License. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA - */ - -#include <console/console.h> -#include <part/fallback_boot.h> -#include <boot/elf.h> -#include <boot/elf_boot.h> -#include <boot/coreboot_tables.h> -#include <ip_checksum.h> -#include <stream/read_bytes.h> -#include <stdint.h> -#include <stdlib.h> -#include <string.h> - -/* Maximum physical address we can use for the coreboot bounce buffer. - */ -#ifndef MAX_ADDR -#define MAX_ADDR -1UL -#endif - -extern unsigned char _ram_seg; -extern unsigned char _eram_seg; - -struct segment { - struct segment *next; - struct segment *prev; - struct segment *phdr_next; - struct segment *phdr_prev; - unsigned long s_addr; - unsigned long s_memsz; - unsigned long s_offset; - unsigned long s_filesz; -}; - -struct verify_callback { - struct verify_callback *next; - int (*callback)(struct verify_callback *vcb, - Elf_ehdr *ehdr, Elf_phdr *phdr, struct segment *head); - unsigned long desc_offset; - unsigned long desc_addr; -}; - -struct ip_checksum_vcb { - struct verify_callback data; - unsigned short ip_checksum; -}; - -int verify_ip_checksum( - struct verify_callback *vcb, - Elf_ehdr *ehdr, Elf_phdr *phdr, struct segment *head) -{ - struct ip_checksum_vcb *cb; - struct segment *ptr; - unsigned long bytes; - unsigned long checksum; - unsigned char buff[2], *n_desc; - cb = (struct ip_checksum_vcb *)vcb; - /* zero the checksum so it's value won't - * get in the way of verifying the checksum. - */ - n_desc = 0; - if (vcb->desc_addr) { - n_desc = (unsigned char *)(vcb->desc_addr); - memcpy(buff, n_desc, 2); - memset(n_desc, 0, 2); - } - bytes = 0; - checksum = compute_ip_checksum(ehdr, sizeof(*ehdr)); - bytes += sizeof(*ehdr); - checksum = add_ip_checksums(bytes, checksum, - compute_ip_checksum(phdr, ehdr->e_phnum*sizeof(*phdr))); - bytes += ehdr->e_phnum*sizeof(*phdr); - for(ptr = head->phdr_next; ptr != head; ptr = ptr->phdr_next) { - checksum = add_ip_checksums(bytes, checksum, - compute_ip_checksum((void *)ptr->s_addr, ptr->s_memsz)); - bytes += ptr->s_memsz; - } - if (n_desc != 0) { - memcpy(n_desc, buff, 2); - } - if (checksum != cb->ip_checksum) { - printk_err("Image checksum: %04x != computed checksum: %04lx\n", - cb->ip_checksum, checksum); - } - return checksum == cb->ip_checksum; -} - -/* The problem: - * Static executables all want to share the same addresses - * in memory because only a few addresses are reliably present on - * a machine, and implementing general relocation is hard. - * - * The solution: - * - Allocate a buffer the size of the coreboot image plus additional - * required space. - * - Anything that would overwrite coreboot copy into the lower part of - * the buffer. - * - After loading an ELF image copy coreboot to the top of the buffer. - * - Then jump to the loaded image. - * - * Benefits: - * - Nearly arbitrary standalone executables can be loaded. - * - Coreboot is preserved, so it can be returned to. - * - The implementation is still relatively simple, - * and much simpler then the general case implemented in kexec. - * - */ - -static unsigned long bounce_size; - -static unsigned long get_bounce_buffer(struct lb_memory *mem) -{ - unsigned long lb_size; - unsigned long mem_entries; - unsigned long buffer; - int i; - lb_size = (unsigned long)(&_eram_seg - &_ram_seg); - /* Double coreboot size so I have somewhere to place a copy to return to */ - bounce_size = lb_size; - lb_size = bounce_size + lb_size; - mem_entries = (mem->size - sizeof(*mem))/sizeof(mem->map[0]); - buffer = 0; - for(i = 0; i < mem_entries; i++) { - unsigned long mstart, mend; - unsigned long msize; - unsigned long tbuffer; - if (mem->map[i].type != LB_MEM_RAM) - continue; - if (unpack_lb64(mem->map[i].start) > MAX_ADDR) - continue; - if (unpack_lb64(mem->map[i].size) < lb_size) - continue; - mstart = unpack_lb64(mem->map[i].start); - msize = MAX_ADDR - mstart +1; - if (msize > unpack_lb64(mem->map[i].size)) - msize = unpack_lb64(mem->map[i].size); - mend = mstart + msize; - tbuffer = mend - lb_size; - if (tbuffer < buffer) - continue; - buffer = tbuffer; - } - return buffer; -} - - -static struct verify_callback *process_elf_notes( - unsigned char *header, - unsigned long offset, unsigned long length) -{ - struct verify_callback *cb_chain; - unsigned char *note, *end; - unsigned char *program, *version; - - cb_chain = 0; - note = header + offset; - end = note + length; - program = version = 0; - while(note < end) { - Elf_Nhdr *hdr; - unsigned char *n_name, *n_desc, *next; - hdr = (Elf_Nhdr *)note; - n_name = note + sizeof(*hdr); - n_desc = n_name + ((hdr->n_namesz + 3) & ~3); - next = n_desc + ((hdr->n_descsz + 3) & ~3); - if (next > end) { - break; - } - if ((hdr->n_namesz == sizeof(ELF_NOTE_BOOT)) && - (memcmp(n_name, ELF_NOTE_BOOT, sizeof(ELF_NOTE_BOOT)) == 0)) { - switch(hdr->n_type) { - case EIN_PROGRAM_NAME: - if (n_desc[hdr->n_descsz -1] == 0) { - program = n_desc; - } - break; - case EIN_PROGRAM_VERSION: - if (n_desc[hdr->n_descsz -1] == 0) { - version = n_desc; - } - break; - case EIN_PROGRAM_CHECKSUM: - { - struct ip_checksum_vcb *cb; - cb = malloc(sizeof(*cb)); - cb->ip_checksum = *((uint16_t *)n_desc); - cb->data.callback = verify_ip_checksum; - cb->data.next = cb_chain; - cb->data.desc_offset = n_desc - header; - cb_chain = &cb->data; - break; - } - } - } - printk_spew("n_type: %08x n_name(%d): %-*.*s n_desc(%d): %-*.*s\n", - hdr->n_type, - hdr->n_namesz, hdr->n_namesz, hdr->n_namesz, n_name, - hdr->n_descsz,hdr->n_descsz, hdr->n_descsz, n_desc); - note = next; - } - if (program && version) { - printk_info("Loading %s version: %s\n", - program, version); - } - return cb_chain; -} - -static int valid_area(struct lb_memory *mem, unsigned long buffer, - unsigned long start, unsigned long len) -{ - /* Check through all of the memory segments and ensure - * the segment that was passed in is completely contained - * in RAM. - */ - int i; - unsigned long end = start + len; - unsigned long mem_entries = (mem->size - sizeof(*mem))/sizeof(mem->map[0]); - - /* See if I conflict with the bounce buffer */ - if (end >= buffer) { - return 0; - } - - /* Walk through the table of valid memory ranges and see if I - * have a match. - */ - for(i = 0; i < mem_entries; i++) { - uint64_t mstart, mend; - uint32_t mtype; - mtype = mem->map[i].type; - mstart = unpack_lb64(mem->map[i].start); - mend = mstart + unpack_lb64(mem->map[i].size); - if ((mtype == LB_MEM_RAM) && (start < mend) && (end > mstart)) { - break; - } - if ((mtype == LB_MEM_TABLE) && (start < mend) && (end > mstart)) { - printk_err("Payload is overwriting Coreboot tables.\n"); - break; - } - } - if (i == mem_entries) { - printk_err("No matching ram area found for range:\n"); - printk_err(" [0x%016lx, 0x%016lx)\n", start, end); - printk_err("Ram areas\n"); - for(i = 0; i < mem_entries; i++) { - uint64_t mstart, mend; - uint32_t mtype; - mtype = mem->map[i].type; - mstart = unpack_lb64(mem->map[i].start); - mend = mstart + unpack_lb64(mem->map[i].size); - printk_err(" [0x%016lx, 0x%016lx) %s\n", - (unsigned long)mstart, - (unsigned long)mend, - (mtype == LB_MEM_RAM)?"RAM":"Reserved"); - - } - return 0; - } - return 1; -} - -static void relocate_segment(unsigned long buffer, struct segment *seg) -{ - /* Modify all segments that want to load onto coreboot - * to load onto the bounce buffer instead. - */ - unsigned long lb_start = (unsigned long)&_ram_seg; - unsigned long lb_end = (unsigned long)&_eram_seg; - unsigned long start, middle, end; - - printk_spew("lb: [0x%016lx, 0x%016lx)\n", - lb_start, lb_end); - - start = seg->s_addr; - middle = start + seg->s_filesz; - end = start + seg->s_memsz; - /* I don't conflict with coreboot so get out of here */ - if ((end <= lb_start) || (start >= lb_end)) - return; - - printk_spew("segment: [0x%016lx, 0x%016lx, 0x%016lx)\n", - start, middle, end); - - /* Slice off a piece at the beginning - * that doesn't conflict with coreboot. - */ - if (start < lb_start) { - struct segment *new; - unsigned long len = lb_start - start; - new = malloc(sizeof(*new)); - *new = *seg; - new->s_memsz = len; - seg->s_memsz -= len; - seg->s_addr += len; - seg->s_offset += len; - if (seg->s_filesz > len) { - new->s_filesz = len; - seg->s_filesz -= len; - } else { - seg->s_filesz = 0; - } - - /* Order by stream offset */ - new->next = seg; - new->prev = seg->prev; - seg->prev->next = new; - seg->prev = new; - /* Order by original program header order */ - new->phdr_next = seg; - new->phdr_prev = seg->phdr_prev; - seg->phdr_prev->phdr_next = new; - seg->phdr_prev = new; - - /* compute the new value of start */ - start = seg->s_addr; - - printk_spew(" early: [0x%016lx, 0x%016lx, 0x%016lx)\n", - new->s_addr, - new->s_addr + new->s_filesz, - new->s_addr + new->s_memsz); - } - - /* Slice off a piece at the end - * that doesn't conflict with coreboot - */ - if (end > lb_end) { - unsigned long len = lb_end - start; - struct segment *new; - new = malloc(sizeof(*new)); - *new = *seg; - seg->s_memsz = len; - new->s_memsz -= len; - new->s_addr += len; - new->s_offset += len; - if (seg->s_filesz > len) { - seg->s_filesz = len; - new->s_filesz -= len; - } else { - new->s_filesz = 0; - } - /* Order by stream offset */ - new->next = seg->next; - new->prev = seg; - seg->next->prev = new; - seg->next = new; - /* Order by original program header order */ - new->phdr_next = seg->phdr_next; - new->phdr_prev = seg; - seg->phdr_next->phdr_prev = new; - seg->phdr_next = new; - - printk_spew(" late: [0x%016lx, 0x%016lx, 0x%016lx)\n", - new->s_addr, - new->s_addr + new->s_filesz, - new->s_addr + new->s_memsz); - - } - /* Now retarget this segment onto the bounce buffer */ - seg->s_addr = buffer + (seg->s_addr - lb_start); - - printk_spew(" bounce: [0x%016lx, 0x%016lx, 0x%016lx)\n", - seg->s_addr, - seg->s_addr + seg->s_filesz, - seg->s_addr + seg->s_memsz); -} - - -static int build_elf_segment_list( - struct segment *head, - unsigned long bounce_buffer, struct lb_memory *mem, - Elf_phdr *phdr, int headers) -{ - struct segment *ptr; - int i; - memset(head, 0, sizeof(*head)); - head->phdr_next = head->phdr_prev = head; - head->next = head->prev = head; - for(i = 0; i < headers; i++) { - struct segment *new; - /* Ignore data that I don't need to handle */ - if (phdr[i].p_type != PT_LOAD) { - printk_debug("Dropping non PT_LOAD segment\n"); - continue; - } - if (phdr[i].p_memsz == 0) { - printk_debug("Dropping empty segment\n"); - continue; - } - new = malloc(sizeof(*new)); - new->s_addr = phdr[i].p_paddr; - new->s_memsz = phdr[i].p_memsz; - new->s_offset = phdr[i].p_offset; - new->s_filesz = phdr[i].p_filesz; - printk_debug("New segment addr 0x%lx size 0x%lx offset 0x%lx filesize 0x%lx\n", - new->s_addr, new->s_memsz, new->s_offset, new->s_filesz); - /* Clean up the values */ - if (new->s_filesz > new->s_memsz) { - new->s_filesz = new->s_memsz; - } - printk_debug("(cleaned up) New segment addr 0x%lx size 0x%lx offset 0x%lx filesize 0x%lx\n", - new->s_addr, new->s_memsz, new->s_offset, new->s_filesz); - for(ptr = head->next; ptr != head; ptr = ptr->next) { - if (new->s_offset < ptr->s_offset) - break; - } - /* Order by stream offset */ - new->next = ptr; - new->prev = ptr->prev; - ptr->prev->next = new; - ptr->prev = new; - /* Order by original program header order */ - new->phdr_next = head; - new->phdr_prev = head->phdr_prev; - head->phdr_prev->phdr_next = new; - head->phdr_prev = new; - - /* Verify the memory addresses in the segment are valid */ - if (!valid_area(mem, bounce_buffer, new->s_addr, new->s_memsz)) - goto out; - - /* Modify the segment to load onto the bounce_buffer if necessary. - */ - relocate_segment(bounce_buffer, new); - } - return 1; - out: - return 0; -} - -static int load_elf_segments( - struct segment *head, unsigned char *header, unsigned long header_size) -{ - unsigned long offset; - struct segment *ptr; - - offset = 0; - for(ptr = head->next; ptr != head; ptr = ptr->next) { - unsigned long start_offset; - unsigned long skip_bytes, read_bytes; - unsigned char *dest, *middle, *end; - byte_offset_t result; - printk_debug("Loading Segment: addr: 0x%016lx memsz: 0x%016lx filesz: 0x%016lx\n", - ptr->s_addr, ptr->s_memsz, ptr->s_filesz); - - /* Compute the boundaries of the segment */ - dest = (unsigned char *)(ptr->s_addr); - end = dest + ptr->s_memsz; - middle = dest + ptr->s_filesz; - start_offset = ptr->s_offset; - /* Ignore s_offset if I have a pure bss segment */ - if (ptr->s_filesz == 0) { - start_offset = offset; - } - - printk_spew("[ 0x%016lx, %016lx, 0x%016lx) <- %016lx\n", - (unsigned long)dest, - (unsigned long)middle, - (unsigned long)end, - (unsigned long)start_offset); - - /* Skip intial buffer unused bytes */ - if (offset < header_size) { - if (start_offset < header_size) { - offset = start_offset; - } else { - offset = header_size; - } - } - - /* Skip the unused bytes */ - skip_bytes = start_offset - offset; - if (skip_bytes && - ((result = stream_skip(skip_bytes)) != skip_bytes)) { - printk_err("ERROR: Skip of %ld bytes skipped %ld bytes\n", - skip_bytes, result); - goto out; - } - offset = start_offset; - - /* Copy data from the initial buffer */ - if (offset < header_size) { - size_t len; - if ((ptr->s_filesz + start_offset) > header_size) { - len = header_size - start_offset; - } - else { - len = ptr->s_filesz; - } - memcpy(dest, &header[start_offset], len); - dest += len; - } - - /* Read the segment into memory */ - read_bytes = middle - dest; - if (read_bytes && - ((result = stream_read(dest, read_bytes)) != read_bytes)) { - printk_err("ERROR: Read of %ld bytes read %ld bytes...\n", - read_bytes, result); - goto out; - } - offset += ptr->s_filesz; - - /* Zero the extra bytes between middle & end */ - if (middle < end) { - printk_debug("Clearing Segment: addr: 0x%016lx memsz: 0x%016lx\n", - (unsigned long)middle, (unsigned long)(end - middle)); - - /* Zero the extra bytes */ - memset(middle, 0, end - middle); - } - } - return 1; - out: - return 0; -} - -static int verify_loaded_image( - struct verify_callback *vcb, - Elf_ehdr *ehdr, Elf_phdr *phdr, - struct segment *head - ) -{ - struct segment *ptr; - int ok; - ok = 1; - for(; ok && vcb ; vcb = vcb->next) { - /* Find where the note is loaded */ - /* The whole note must be loaded intact - * so an address of 0 for the descriptor is impossible - */ - vcb->desc_addr = 0; - for(ptr = head->next; ptr != head; ptr = ptr->next) { - unsigned long desc_addr; - desc_addr = ptr->s_addr + vcb->desc_offset - ptr->s_offset; - if ((desc_addr >= ptr->s_addr) && - (desc_addr < (ptr->s_addr + ptr->s_filesz))) { - vcb->desc_addr = desc_addr; - } - } - ok = vcb->callback(vcb, ehdr, phdr, head); - } - return ok; -} - -int elfload(struct lb_memory *mem, - unsigned char *header, unsigned long header_size) -{ - Elf_ehdr *ehdr; - Elf_phdr *phdr; - void *entry; - struct segment head; - struct verify_callback *cb_chain; - unsigned long bounce_buffer; - - /* Find a bounce buffer so I can load to coreboot's current location */ - bounce_buffer = get_bounce_buffer(mem); - if (!bounce_buffer) { - printk_err("Could not find a bounce buffer...\n"); - goto out; - } - - ehdr = (Elf_ehdr *)header; - entry = (void *)(ehdr->e_entry); - phdr = (Elf_phdr *)(&header[ehdr->e_phoff]); - - /* Digest elf note information... */ - cb_chain = 0; - if ((phdr[0].p_type == PT_NOTE) && - ((phdr[0].p_offset + phdr[0].p_filesz) < header_size)) { - cb_chain = process_elf_notes(header, - phdr[0].p_offset, phdr[0].p_filesz); - } - - /* Preprocess the elf segments */ - if (!build_elf_segment_list(&head, - bounce_buffer, mem, phdr, ehdr->e_phnum)) - goto out; - - /* Load the segments */ - if (!load_elf_segments(&head, header, header_size)) - goto out; - - printk_spew("Loaded segments\n"); - /* Verify the loaded image */ - if (!verify_loaded_image(cb_chain, ehdr, phdr, &head)) - goto out; - - printk_spew("verified segments\n"); - /* Shutdown the stream device */ - stream_fini(); - - printk_spew("closed down stream\n"); - /* Reset to booting from this image as late as possible */ - boot_successful(); - - printk_debug("Jumping to boot code at %p\n", entry); - post_code(0xfe); - - /* Jump to kernel */ - jmp_to_elf_entry(entry, bounce_buffer, bounce_size); - return 1; - - out: - return 0; -} - -int elfboot(struct lb_memory *mem) -{ - Elf_ehdr *ehdr; - static unsigned char header[ELF_HEAD_SIZE]; - int header_offset; - int i, result; - - result = 0; - printk_debug("\nelfboot: Attempting to load payload.\n"); - post_code(0xf8); - - if (stream_init() < 0) { - printk_err("Could not initialize driver...\n"); - goto out; - } - - /* Read in the initial ELF_HEAD_SIZE bytes */ - if (stream_read(header, ELF_HEAD_SIZE) != ELF_HEAD_SIZE) { - printk_err("Read failed...\n"); - goto out; - } - /* Scan for an elf header */ - header_offset = -1; - for(i = 0; i < ELF_HEAD_SIZE - (sizeof(Elf_ehdr) + sizeof(Elf_phdr)); i+=16) { - ehdr = (Elf_ehdr *)(&header[i]); - if (memcmp(ehdr->e_ident, ELFMAG, 4) != 0) { - printk_debug("No header at %d\n", i); - continue; - } - printk_debug("Found ELF candidate at offset %d\n", i); - /* Sanity check the elf header */ - if ((ehdr->e_type == ET_EXEC) && - elf_check_arch(ehdr) && - (ehdr->e_ident[EI_VERSION] == EV_CURRENT) && - (ehdr->e_version == EV_CURRENT) && - (ehdr->e_ehsize == sizeof(Elf_ehdr)) && - (ehdr->e_phentsize = sizeof(Elf_phdr)) && - (ehdr->e_phoff < (ELF_HEAD_SIZE - i)) && - ((ehdr->e_phoff + (ehdr->e_phentsize * ehdr->e_phnum)) <= - (ELF_HEAD_SIZE - i))) { - header_offset = i; - break; - } - ehdr = 0; - } - printk_debug("header_offset is %d\n", header_offset); - if (header_offset == -1) { - goto out; - } - - printk_debug("Try to load at offset 0x%x\n", header_offset); - result = elfload(mem, - header + header_offset , ELF_HEAD_SIZE - header_offset); - out: - if (!result) { - /* Shutdown the stream device */ - stream_fini(); - - printk_err("Can not load ELF Image.\n"); - - post_code(0xff); - } - return 0; - -} |