예제 #1
0
파일: process.c 프로젝트: CyberjujuM/tacos
int exec_elf(char* cmdline, int orphan)
{	
	char* execpath = strdup(cmdline);
	int ret = -1;
	int offset = 0;
	
	while(execpath[offset] != ' ' && execpath[offset] != '\0')
		offset++;
	
	execpath[offset] = '\0';
	
	int fd = open(execpath, O_RDONLY);
	
	process_init_data_t init_data;
	
	if(fd != -1)
	{
		ret = 0;
			
		init_data.name	= execpath;
		init_data.stack_size = 0x1000;
		init_data.priority = 0;
		
		init_data.args = cmdline;
		init_data.envp = environ;
		
		init_data.mem_size = elf_size(fd);
		init_data.data = malloc(init_data.mem_size);
		init_data.entry_point = load_elf(fd, init_data.data);
		
		init_data.file = load_elf_file(fd);

		init_data.ppid = orphan?0:getpid();
		init_data.exec_type = EXEC_ELF;

		syscall(SYS_EXEC, (uint32_t)&init_data, (uint32_t)NULL, (uint32_t)NULL);
		
		free(init_data.data);
	}
	return ret;
}
static int xc_dom_load_elf_symtab(struct xc_dom_image *dom,
                                  struct elf_binary *elf, int load)
{
    struct elf_binary syms;
    const elf_shdr *shdr, *shdr2;
    xen_vaddr_t symtab, maxaddr;
    char *hdr;
    size_t size;
    int h, count, type, i, tables = 0;

    if ( elf_swap(elf) )
    {
        xc_dom_printf("%s: non-native byte order, bsd symtab not supported\n",
                      __FUNCTION__);
        return 0;
    }

    if ( load )
    {
        if ( !dom->bsd_symtab_start )
            return 0;
        size = dom->kernel_seg.vend - dom->bsd_symtab_start;
        hdr  = xc_dom_vaddr_to_ptr(dom, dom->bsd_symtab_start);
        *(int *)hdr = size - sizeof(int);
    }
    else
    {
        size = sizeof(int) + elf_size(elf, elf->ehdr) +
            elf_shdr_count(elf) * elf_size(elf, shdr);
        hdr = xc_dom_malloc(dom, size);
        if ( hdr == NULL )
            return 0;
        dom->bsd_symtab_start = elf_round_up(&syms, dom->kernel_seg.vend);
    }

    memcpy(hdr + sizeof(int),
           elf->image,
           elf_size(elf, elf->ehdr));
    memcpy(hdr + sizeof(int) + elf_size(elf, elf->ehdr),
           elf->image + elf_uval(elf, elf->ehdr, e_shoff),
           elf_shdr_count(elf) * elf_size(elf, shdr));
    if ( elf_64bit(elf) )
    {
        Elf64_Ehdr *ehdr = (Elf64_Ehdr *)(hdr + sizeof(int));
        ehdr->e_phoff = 0;
        ehdr->e_phentsize = 0;
        ehdr->e_phnum = 0;
        ehdr->e_shoff = elf_size(elf, elf->ehdr);
        ehdr->e_shstrndx = SHN_UNDEF;
    }
    else
    {
        Elf32_Ehdr *ehdr = (Elf32_Ehdr *)(hdr + sizeof(int));
        ehdr->e_phoff = 0;
        ehdr->e_phentsize = 0;
        ehdr->e_phnum = 0;
        ehdr->e_shoff = elf_size(elf, elf->ehdr);
        ehdr->e_shstrndx = SHN_UNDEF;
    }
    if ( elf_init(&syms, hdr + sizeof(int), size - sizeof(int)) )
        return -1;
    if ( xc_dom_logfile )
        elf_set_logfile(&syms, xc_dom_logfile, 1);

    symtab = dom->bsd_symtab_start + sizeof(int);
    maxaddr = elf_round_up(&syms, symtab + elf_size(&syms, syms.ehdr) +
                           elf_shdr_count(&syms) * elf_size(&syms, shdr));

    xc_dom_printf("%s/%s: bsd_symtab_start=%" PRIx64 ", kernel.end=0x%" PRIx64
                  " -- symtab=0x%" PRIx64 ", maxaddr=0x%" PRIx64 "\n",
                  __FUNCTION__, load ? "load" : "parse",
                  dom->bsd_symtab_start, dom->kernel_seg.vend,
                  symtab, maxaddr);

    count = elf_shdr_count(&syms);
    for ( h = 0; h < count; h++ )
    {
        shdr = elf_shdr_by_index(&syms, h);
        type = elf_uval(&syms, shdr, sh_type);
        if ( type == SHT_STRTAB )
        {
            /* Look for a strtab @i linked to symtab @h. */
            for ( i = 0; i < count; i++ )
            {
                shdr2 = elf_shdr_by_index(&syms, i);
                if ( (elf_uval(&syms, shdr2, sh_type) == SHT_SYMTAB) &&
                     (elf_uval(&syms, shdr2, sh_link) == h) )
                    break;
            }
            /* Skip symtab @h if we found no corresponding strtab @i. */
            if ( i == count )
            {
                if ( elf_64bit(&syms) )
                    *(Elf64_Off*)(&shdr->e64.sh_offset) = 0;
                else
                    *(Elf32_Off*)(&shdr->e32.sh_offset) = 0;
                continue;
            }
        }

        if ( (type == SHT_STRTAB) || (type == SHT_SYMTAB) )
        {
            /* Mangled to be based on ELF header location. */
            if ( elf_64bit(&syms) )
                *(Elf64_Off*)(&shdr->e64.sh_offset) = maxaddr - symtab;
            else
                *(Elf32_Off*)(&shdr->e32.sh_offset) = maxaddr - symtab;
            size = elf_uval(&syms, shdr, sh_size);
            maxaddr = elf_round_up(&syms, maxaddr + size);
            tables++;
            xc_dom_printf("%s: h=%d %s, size=0x%zx, maxaddr=0x%" PRIx64 "\n",
                          __FUNCTION__, h,
                          type == SHT_SYMTAB ? "symtab" : "strtab",
                          size, maxaddr);

            if ( load )
            {
                shdr2 = elf_shdr_by_index(elf, h);
                memcpy((void*)elf_section_start(&syms, shdr),
                       elf_section_start(elf, shdr2),
                       size);
            }
        }

        /* Name is NULL. */
        if ( elf_64bit(&syms) )
            *(Elf64_Half*)(&shdr->e64.sh_name) = 0;
        else
            *(Elf32_Word*)(&shdr->e32.sh_name) = 0;
    }

    if ( tables == 0 )
    {
        xc_dom_printf("%s: no symbol table present\n", __FUNCTION__);
        dom->bsd_symtab_start = 0;
        return 0;
    }
    if ( !load )
        dom->kernel_seg.vend = maxaddr;
    return 0;
}