+++ /dev/null
-/*
- * 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;
-
-}
projects / coreboot.git / blobdiff