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-rw-r--r--linux-user/elfload.c973
1 files changed, 973 insertions, 0 deletions
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
new file mode 100644
index 0000000000..0ee4f1365b
--- /dev/null
+++ b/linux-user/elfload.c
@@ -0,0 +1,973 @@
+/* This is the Linux kernel elf-loading code, ported into user space */
+
+#include <stdio.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "gemu.h"
+
+#include "linux_bin.h"
+#include "elf.h"
+#include "segment.h"
+
+/* Necessary parameters */
+#define ALPHA_PAGE_SIZE 4096
+#define X86_PAGE_SIZE 4096
+
+#define ALPHA_PAGE_MASK (~(ALPHA_PAGE_SIZE-1))
+#define X86_PAGE_MASK (~(X86_PAGE_SIZE-1))
+
+#define ALPHA_PAGE_ALIGN(addr) ((((addr)+ALPHA_PAGE_SIZE)-1)&ALPHA_PAGE_MASK)
+#define X86_PAGE_ALIGN(addr) ((((addr)+X86_PAGE_SIZE)-1)&X86_PAGE_MASK)
+
+#define NGROUPS 32
+
+#define X86_ELF_EXEC_PAGESIZE X86_PAGE_SIZE
+#define X86_ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(X86_ELF_EXEC_PAGESIZE-1))
+#define X86_ELF_PAGEOFFSET(_v) ((_v) & (X86_ELF_EXEC_PAGESIZE-1))
+
+#define ALPHA_ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ALPHA_PAGE_SIZE-1))
+#define ALPHA_ELF_PAGEOFFSET(_v) ((_v) & (ALPHA_PAGE_SIZE-1))
+
+#define INTERPRETER_NONE 0
+#define INTERPRETER_AOUT 1
+#define INTERPRETER_ELF 2
+
+#define DLINFO_ITEMS 12
+
+/* Where we find X86 libraries... */
+//#define X86_DEFAULT_LIB_DIR "/usr/x86/"
+#define X86_DEFAULT_LIB_DIR "/"
+
+//extern void * mmap4k();
+#define mmap4k(a, b, c, d, e, f) mmap((void *)(a), b, c, d, e, f)
+
+extern unsigned long x86_stack_size;
+
+static int load_aout_interp(void * exptr, int interp_fd);
+
+#ifdef BSWAP_NEEDED
+static void bswap_ehdr(Elf32_Ehdr *ehdr)
+{
+ bswap16s(&ehdr->e_type); /* Object file type */
+ bswap16s(&ehdr->e_machine); /* Architecture */
+ bswap32s(&ehdr->e_version); /* Object file version */
+ bswap32s(&ehdr->e_entry); /* Entry point virtual address */
+ bswap32s(&ehdr->e_phoff); /* Program header table file offset */
+ bswap32s(&ehdr->e_shoff); /* Section header table file offset */
+ bswap32s(&ehdr->e_flags); /* Processor-specific flags */
+ bswap16s(&ehdr->e_ehsize); /* ELF header size in bytes */
+ bswap16s(&ehdr->e_phentsize); /* Program header table entry size */
+ bswap16s(&ehdr->e_phnum); /* Program header table entry count */
+ bswap16s(&ehdr->e_shentsize); /* Section header table entry size */
+ bswap16s(&ehdr->e_shnum); /* Section header table entry count */
+ bswap16s(&ehdr->e_shstrndx); /* Section header string table index */
+}
+
+static void bswap_phdr(Elf32_Phdr *phdr)
+{
+ bswap32s(&phdr->p_type); /* Segment type */
+ bswap32s(&phdr->p_offset); /* Segment file offset */
+ bswap32s(&phdr->p_vaddr); /* Segment virtual address */
+ bswap32s(&phdr->p_paddr); /* Segment physical address */
+ bswap32s(&phdr->p_filesz); /* Segment size in file */
+ bswap32s(&phdr->p_memsz); /* Segment size in memory */
+ bswap32s(&phdr->p_flags); /* Segment flags */
+ bswap32s(&phdr->p_align); /* Segment alignment */
+}
+#endif
+
+static void * get_free_page(void)
+{
+ void * retval;
+
+ /* User-space version of kernel get_free_page. Returns a page-aligned
+ * page-sized chunk of memory.
+ */
+ retval = mmap4k(0, ALPHA_PAGE_SIZE, PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+
+ if((long)retval == -1) {
+ perror("get_free_page");
+ exit(-1);
+ }
+ else {
+ return(retval);
+ }
+}
+
+static void free_page(void * pageaddr)
+{
+ (void)munmap(pageaddr, ALPHA_PAGE_SIZE);
+}
+
+/*
+ * 'copy_string()' copies argument/envelope strings from user
+ * memory to free pages in kernel mem. These are in a format ready
+ * to be put directly into the top of new user memory.
+ *
+ */
+static unsigned long copy_strings(int argc,char ** argv,unsigned long *page,
+ unsigned long p)
+{
+ char *tmp, *tmp1, *pag = NULL;
+ int len, offset = 0;
+
+ if (!p) {
+ return 0; /* bullet-proofing */
+ }
+ while (argc-- > 0) {
+ if (!(tmp1 = tmp = get_user(argv+argc))) {
+ fprintf(stderr, "VFS: argc is wrong");
+ exit(-1);
+ }
+ while (get_user(tmp++));
+ len = tmp - tmp1;
+ if (p < len) { /* this shouldn't happen - 128kB */
+ return 0;
+ }
+ while (len) {
+ --p; --tmp; --len;
+ if (--offset < 0) {
+ offset = p % X86_PAGE_SIZE;
+ if (!(pag = (char *) page[p/X86_PAGE_SIZE]) &&
+ !(pag = (char *) page[p/X86_PAGE_SIZE] =
+ (unsigned long *) get_free_page())) {
+ return 0;
+ }
+ }
+ if (len == 0 || offset == 0) {
+ *(pag + offset) = get_user(tmp);
+ }
+ else {
+ int bytes_to_copy = (len > offset) ? offset : len;
+ tmp -= bytes_to_copy;
+ p -= bytes_to_copy;
+ offset -= bytes_to_copy;
+ len -= bytes_to_copy;
+ memcpy_fromfs(pag + offset, tmp, bytes_to_copy + 1);
+ }
+ }
+ }
+ return p;
+}
+
+static int in_group_p(gid_t g)
+{
+ /* return TRUE if we're in the specified group, FALSE otherwise */
+ int ngroup;
+ int i;
+ gid_t grouplist[NGROUPS];
+
+ ngroup = getgroups(NGROUPS, grouplist);
+ for(i = 0; i < ngroup; i++) {
+ if(grouplist[i] == g) {
+ return 1;
+ }
+ }
+ return 0;
+}
+
+static int count(char ** vec)
+{
+ int i;
+
+ for(i = 0; *vec; i++) {
+ vec++;
+ }
+
+ return(i);
+}
+
+static int prepare_binprm(struct linux_binprm *bprm)
+{
+ struct stat st;
+ int mode;
+ int retval, id_change;
+
+ if(fstat(bprm->fd, &st) < 0) {
+ return(-errno);
+ }
+
+ mode = st.st_mode;
+ if(!S_ISREG(mode)) { /* Must be regular file */
+ return(-EACCES);
+ }
+ if(!(mode & 0111)) { /* Must have at least one execute bit set */
+ return(-EACCES);
+ }
+
+ bprm->e_uid = geteuid();
+ bprm->e_gid = getegid();
+ id_change = 0;
+
+ /* Set-uid? */
+ if(mode & S_ISUID) {
+ bprm->e_uid = st.st_uid;
+ if(bprm->e_uid != geteuid()) {
+ id_change = 1;
+ }
+ }
+
+ /* Set-gid? */
+ /*
+ * If setgid is set but no group execute bit then this
+ * is a candidate for mandatory locking, not a setgid
+ * executable.
+ */
+ if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
+ bprm->e_gid = st.st_gid;
+ if (!in_group_p(bprm->e_gid)) {
+ id_change = 1;
+ }
+ }
+
+ memset(bprm->buf, 0, sizeof(bprm->buf));
+ retval = lseek(bprm->fd, 0L, SEEK_SET);
+ if(retval >= 0) {
+ retval = read(bprm->fd, bprm->buf, 128);
+ }
+ if(retval < 0) {
+ perror("prepare_binprm");
+ exit(-1);
+ /* return(-errno); */
+ }
+ else {
+ return(retval);
+ }
+}
+
+unsigned long setup_arg_pages(unsigned long p, struct linux_binprm * bprm,
+ struct image_info * info)
+{
+ unsigned long stack_base;
+ int i;
+ extern unsigned long stktop;
+
+ stack_base = X86_STACK_TOP - MAX_ARG_PAGES*X86_PAGE_SIZE;
+
+ p += stack_base;
+ if (bprm->loader) {
+ bprm->loader += stack_base;
+ }
+ bprm->exec += stack_base;
+
+ /* Create enough stack to hold everything. If we don't use
+ * it for args, we'll use it for something else...
+ */
+ if(x86_stack_size > MAX_ARG_PAGES*X86_PAGE_SIZE) {
+ if((long)mmap4k((void *)(X86_STACK_TOP-x86_stack_size), x86_stack_size + X86_PAGE_SIZE,
+ PROT_READ | PROT_WRITE,
+ MAP_GROWSDOWN | MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0) == -1) {
+ perror("stk mmap");
+ exit(-1);
+ }
+ }
+ else {
+ if((long)mmap4k((void *)stack_base, (MAX_ARG_PAGES+1)*X86_PAGE_SIZE,
+ PROT_READ | PROT_WRITE,
+ MAP_GROWSDOWN | MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0) == -1) {
+ perror("stk mmap");
+ exit(-1);
+ }
+ }
+
+ stktop = stack_base;
+
+ for (i = 0 ; i < MAX_ARG_PAGES ; i++) {
+ if (bprm->page[i]) {
+ info->rss++;
+
+ memcpy((void *)stack_base, (void *)bprm->page[i], X86_PAGE_SIZE);
+ free_page((void *)bprm->page[i]);
+ }
+ stack_base += X86_PAGE_SIZE;
+ }
+ return p;
+}
+
+static void set_brk(unsigned long start, unsigned long end)
+{
+ /* page-align the start and end addresses... */
+ start = ALPHA_PAGE_ALIGN(start);
+ end = ALPHA_PAGE_ALIGN(end);
+ if (end <= start)
+ return;
+ if((long)mmap4k(start, end - start,
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0) == -1) {
+ perror("cannot mmap brk");
+ exit(-1);
+ }
+}
+
+
+/* We need to explicitly zero any fractional pages
+ after the data section (i.e. bss). This would
+ contain the junk from the file that should not
+ be in memory */
+
+
+static void padzero(unsigned long elf_bss)
+{
+ unsigned long nbyte;
+ char * fpnt;
+
+ nbyte = elf_bss & (ALPHA_PAGE_SIZE-1); /* was X86_PAGE_SIZE - JRP */
+ if (nbyte) {
+ nbyte = ALPHA_PAGE_SIZE - nbyte;
+ fpnt = (char *) elf_bss;
+ do {
+ *fpnt++ = 0;
+ } while (--nbyte);
+ }
+}
+
+static unsigned int * create_elf_tables(char *p, int argc, int envc,
+ struct elfhdr * exec,
+ unsigned long load_addr,
+ unsigned long interp_load_addr, int ibcs,
+ struct image_info *info)
+{
+ unsigned int *argv, *envp, *dlinfo;
+ unsigned int *sp;
+ char **alpha_envp;
+
+ /*
+ * Force 16 byte alignment here for generality.
+ */
+ sp = (unsigned int *) (~15UL & (unsigned long) p);
+ sp -= exec ? DLINFO_ITEMS*2 : 2;
+ dlinfo = sp;
+ sp -= envc+1;
+ envp = sp;
+ sp -= argc+1;
+ argv = sp;
+ if (!ibcs) {
+ put_user(envp,--sp);
+ put_user(argv,--sp);
+ }
+ alpha_envp = (char **)malloc((envc+1) * sizeof(char *));
+
+#define NEW_AUX_ENT(id, val) \
+ put_user ((id), dlinfo++); \
+ put_user ((val), dlinfo++)
+
+ if (exec) { /* Put this here for an ELF program interpreter */
+ struct elf_phdr * eppnt;
+ eppnt = (struct elf_phdr *)((unsigned long)exec->e_phoff);
+
+ NEW_AUX_ENT (AT_PHDR, (unsigned int)(load_addr + exec->e_phoff));
+ NEW_AUX_ENT (AT_PHENT, (unsigned int)(sizeof (struct elf_phdr)));
+ NEW_AUX_ENT (AT_PHNUM, (unsigned int)(exec->e_phnum));
+ NEW_AUX_ENT (AT_PAGESZ, (unsigned int)(ALPHA_PAGE_SIZE));
+ NEW_AUX_ENT (AT_BASE, (unsigned int)(interp_load_addr));
+ NEW_AUX_ENT (AT_FLAGS, (unsigned int)0);
+ NEW_AUX_ENT (AT_ENTRY, (unsigned int) exec->e_entry);
+ NEW_AUX_ENT (AT_UID, (unsigned int) getuid());
+ NEW_AUX_ENT (AT_EUID, (unsigned int) geteuid());
+ NEW_AUX_ENT (AT_GID, (unsigned int) getgid());
+ NEW_AUX_ENT (AT_EGID, (unsigned int) getegid());
+ }
+ NEW_AUX_ENT (AT_NULL, 0);
+#undef NEW_AUX_ENT
+ put_user((unsigned int)argc,--sp);
+ info->arg_start = (unsigned int)((unsigned long)p & 0xffffffff);
+ while (argc-->0) {
+ put_user(p,argv++);
+ while (get_user(p++)) /* nothing */ ;
+ }
+ put_user(0,argv);
+ info->arg_end = info->env_start = (unsigned int)((unsigned long)p & 0xffffffff);
+ __environ = alpha_envp;
+ while (envc-->0) {
+ *alpha_envp++ = (char *)p;
+ put_user(p,envp++);
+ while (get_user(p++)) /* nothing */ ;
+ }
+ put_user(0,envp);
+ *alpha_envp = 0;
+ info->env_end = (unsigned int)((unsigned long)p & 0xffffffff);
+ return sp;
+}
+
+
+
+static unsigned long load_elf_interp(struct elfhdr * interp_elf_ex,
+ int interpreter_fd,
+ unsigned long *interp_load_addr)
+{
+ struct elf_phdr *elf_phdata = NULL;
+ struct elf_phdr *eppnt;
+ unsigned long load_addr;
+ int load_addr_set = 0;
+ int retval;
+ unsigned long last_bss, elf_bss;
+ unsigned long error;
+ int i;
+
+ elf_bss = 0;
+ last_bss = 0;
+ error = 0;
+
+ /* We put this here so that mmap will search for the *first*
+ * available memory...
+ */
+ load_addr = INTERP_LOADADDR;
+
+ /* First of all, some simple consistency checks */
+ if ((interp_elf_ex->e_type != ET_EXEC &&
+ interp_elf_ex->e_type != ET_DYN) ||
+ !elf_check_arch(interp_elf_ex->e_machine)) {
+ return ~0UL;
+ }
+
+ /* Now read in all of the header information */
+
+ if (sizeof(struct elf_phdr) * interp_elf_ex->e_phnum > X86_PAGE_SIZE)
+ return ~0UL;
+
+ elf_phdata = (struct elf_phdr *)
+ malloc(sizeof(struct elf_phdr) * interp_elf_ex->e_phnum);
+
+ if (!elf_phdata)
+ return ~0UL;
+
+ /*
+ * If the size of this structure has changed, then punt, since
+ * we will be doing the wrong thing.
+ */
+ if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr))
+ {
+ free(elf_phdata);
+ return ~0UL;
+ }
+
+ retval = lseek(interpreter_fd, interp_elf_ex->e_phoff, SEEK_SET);
+ if(retval >= 0) {
+ retval = read(interpreter_fd,
+ (char *) elf_phdata,
+ sizeof(struct elf_phdr) * interp_elf_ex->e_phnum);
+ }
+
+ if (retval < 0) {
+ perror("load_elf_interp");
+ exit(-1);
+ free (elf_phdata);
+ return retval;
+ }
+#ifdef BSWAP_NEEDED
+ eppnt = elf_phdata;
+ for (i=0; i<interp_elf_ex->e_phnum; i++, eppnt++) {
+ bswap_phdr(eppnt);
+ }
+#endif
+ eppnt = elf_phdata;
+ for(i=0; i<interp_elf_ex->e_phnum; i++, eppnt++)
+ if (eppnt->p_type == PT_LOAD) {
+ int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
+ int elf_prot = 0;
+ unsigned long vaddr = 0;
+ unsigned long k;
+
+ if (eppnt->p_flags & PF_R) elf_prot = PROT_READ;
+ if (eppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
+ if (eppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
+ if (interp_elf_ex->e_type == ET_EXEC || load_addr_set) {
+ elf_type |= MAP_FIXED;
+ vaddr = eppnt->p_vaddr;
+ }
+ error = (unsigned long)mmap4k(load_addr+X86_ELF_PAGESTART(vaddr),
+ eppnt->p_filesz + X86_ELF_PAGEOFFSET(eppnt->p_vaddr),
+ elf_prot,
+ elf_type,
+ interpreter_fd,
+ eppnt->p_offset - X86_ELF_PAGEOFFSET(eppnt->p_vaddr));
+
+ if (error > -1024UL) {
+ /* Real error */
+ close(interpreter_fd);
+ free(elf_phdata);
+ return ~0UL;
+ }
+
+ if (!load_addr_set && interp_elf_ex->e_type == ET_DYN) {
+ load_addr = error;
+ load_addr_set = 1;
+ }
+
+ /*
+ * Find the end of the file mapping for this phdr, and keep
+ * track of the largest address we see for this.
+ */
+ k = load_addr + eppnt->p_vaddr + eppnt->p_filesz;
+ if (k > elf_bss) elf_bss = k;
+
+ /*
+ * Do the same thing for the memory mapping - between
+ * elf_bss and last_bss is the bss section.
+ */
+ k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
+ if (k > last_bss) last_bss = k;
+ }
+
+ /* Now use mmap to map the library into memory. */
+
+ close(interpreter_fd);
+
+ /*
+ * Now fill out the bss section. First pad the last page up
+ * to the page boundary, and then perform a mmap to make sure
+ * that there are zeromapped pages up to and including the last
+ * bss page.
+ */
+ padzero(elf_bss);
+ elf_bss = X86_ELF_PAGESTART(elf_bss + ALPHA_PAGE_SIZE - 1); /* What we have mapped so far */
+
+ /* Map the last of the bss segment */
+ if (last_bss > elf_bss) {
+ mmap4k(elf_bss, last_bss-elf_bss,
+ PROT_READ|PROT_WRITE|PROT_EXEC,
+ MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+ }
+ free(elf_phdata);
+
+ *interp_load_addr = load_addr;
+ return ((unsigned long) interp_elf_ex->e_entry) + load_addr;
+}
+
+
+
+static int load_elf_binary(struct linux_binprm * bprm, struct pt_regs * regs,
+ struct image_info * info)
+{
+ struct elfhdr elf_ex;
+ struct elfhdr interp_elf_ex;
+ struct exec interp_ex;
+ int interpreter_fd = -1; /* avoid warning */
+ unsigned long load_addr;
+ int load_addr_set = 0;
+ unsigned int interpreter_type = INTERPRETER_NONE;
+ unsigned char ibcs2_interpreter;
+ int i;
+ void * mapped_addr;
+ struct elf_phdr * elf_ppnt;
+ struct elf_phdr *elf_phdata;
+ unsigned long elf_bss, k, elf_brk;
+ int retval;
+ char * elf_interpreter;
+ unsigned long elf_entry, interp_load_addr = 0;
+ int status;
+ unsigned long start_code, end_code, end_data;
+ unsigned long elf_stack;
+ char passed_fileno[6];
+
+ ibcs2_interpreter = 0;
+ status = 0;
+ load_addr = 0;
+ elf_ex = *((struct elfhdr *) bprm->buf); /* exec-header */
+#ifdef BSWAP_NEEDED
+ bswap_ehdr(&elf_ex);
+#endif
+
+ if (elf_ex.e_ident[0] != 0x7f ||
+ strncmp(&elf_ex.e_ident[1], "ELF",3) != 0) {
+ return -ENOEXEC;
+ }
+
+
+ /* First of all, some simple consistency checks */
+ if ((elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN) ||
+ (! elf_check_arch(elf_ex.e_machine))) {
+ return -ENOEXEC;
+ }
+
+ /* Now read in all of the header information */
+
+ elf_phdata = (struct elf_phdr *)malloc(elf_ex.e_phentsize*elf_ex.e_phnum);
+ if (elf_phdata == NULL) {
+ return -ENOMEM;
+ }
+
+ retval = lseek(bprm->fd, elf_ex.e_phoff, SEEK_SET);
+ if(retval > 0) {
+ retval = read(bprm->fd, (char *) elf_phdata,
+ elf_ex.e_phentsize * elf_ex.e_phnum);
+ }
+
+ if (retval < 0) {
+ perror("load_elf_binary");
+ exit(-1);
+ free (elf_phdata);
+ return -errno;
+ }
+
+ elf_ppnt = elf_phdata;
+
+ elf_bss = 0;
+ elf_brk = 0;
+
+
+ elf_stack = ~0UL;
+ elf_interpreter = NULL;
+ start_code = ~0UL;
+ end_code = 0;
+ end_data = 0;
+
+ for(i=0;i < elf_ex.e_phnum; i++) {
+ if (elf_ppnt->p_type == PT_INTERP) {
+ if ( elf_interpreter != NULL )
+ {
+ free (elf_phdata);
+ free(elf_interpreter);
+ close(bprm->fd);
+ return -EINVAL;
+ }
+
+ /* This is the program interpreter used for
+ * shared libraries - for now assume that this
+ * is an a.out format binary
+ */
+
+ elf_interpreter = (char *)malloc(elf_ppnt->p_filesz+strlen(X86_DEFAULT_LIB_DIR));
+
+ if (elf_interpreter == NULL) {
+ free (elf_phdata);
+ close(bprm->fd);
+ return -ENOMEM;
+ }
+
+ strcpy(elf_interpreter, X86_DEFAULT_LIB_DIR);
+ retval = lseek(bprm->fd, elf_ppnt->p_offset, SEEK_SET);
+ if(retval >= 0) {
+ retval = read(bprm->fd,
+ elf_interpreter+strlen(X86_DEFAULT_LIB_DIR),
+ elf_ppnt->p_filesz);
+ }
+ if(retval < 0) {
+ perror("load_elf_binary2");
+ exit(-1);
+ }
+
+ /* If the program interpreter is one of these two,
+ then assume an iBCS2 image. Otherwise assume
+ a native linux image. */
+
+ /* JRP - Need to add X86 lib dir stuff here... */
+
+ if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 ||
+ strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0) {
+ ibcs2_interpreter = 1;
+ }
+
+#if 0
+ printf("Using ELF interpreter %s\n", elf_interpreter);
+#endif
+ if (retval >= 0) {
+ retval = open(elf_interpreter, O_RDONLY);
+ if(retval >= 0) {
+ interpreter_fd = retval;
+ }
+ else {
+ perror(elf_interpreter);
+ exit(-1);
+ /* retval = -errno; */
+ }
+ }
+
+ if (retval >= 0) {
+ retval = lseek(interpreter_fd, 0, SEEK_SET);
+ if(retval >= 0) {
+ retval = read(interpreter_fd,bprm->buf,128);
+ }
+ }
+ if (retval >= 0) {
+ interp_ex = *((struct exec *) bprm->buf); /* aout exec-header */
+ interp_elf_ex=*((struct elfhdr *) bprm->buf); /* elf exec-header */
+ }
+ if (retval < 0) {
+ perror("load_elf_binary3");
+ exit(-1);
+ free (elf_phdata);
+ free(elf_interpreter);
+ close(bprm->fd);
+ return retval;
+ }
+ }
+ elf_ppnt++;
+ }
+
+ /* Some simple consistency checks for the interpreter */
+ if (elf_interpreter){
+ interpreter_type = INTERPRETER_ELF | INTERPRETER_AOUT;
+
+ /* Now figure out which format our binary is */
+ if ((N_MAGIC(interp_ex) != OMAGIC) && (N_MAGIC(interp_ex) != ZMAGIC) &&
+ (N_MAGIC(interp_ex) != QMAGIC)) {
+ interpreter_type = INTERPRETER_ELF;
+ }
+
+ if (interp_elf_ex.e_ident[0] != 0x7f ||
+ strncmp(&interp_elf_ex.e_ident[1], "ELF",3) != 0) {
+ interpreter_type &= ~INTERPRETER_ELF;
+ }
+
+ if (!interpreter_type) {
+ free(elf_interpreter);
+ free(elf_phdata);
+ close(bprm->fd);
+ return -ELIBBAD;
+ }
+ }
+
+ /* OK, we are done with that, now set up the arg stuff,
+ and then start this sucker up */
+
+ if (!bprm->sh_bang) {
+ char * passed_p;
+
+ if (interpreter_type == INTERPRETER_AOUT) {
+ sprintf(passed_fileno, "%d", bprm->fd);
+ passed_p = passed_fileno;
+
+ if (elf_interpreter) {
+ bprm->p = copy_strings(1,&passed_p,bprm->page,bprm->p);
+ bprm->argc++;
+ }
+ }
+ if (!bprm->p) {
+ if (elf_interpreter) {
+ free(elf_interpreter);
+ }
+ free (elf_phdata);
+ close(bprm->fd);
+ return -E2BIG;
+ }
+ }
+
+ /* OK, This is the point of no return */
+ info->end_data = 0;
+ info->end_code = 0;
+ info->start_mmap = (unsigned long)ELF_START_MMAP;
+ info->mmap = 0;
+ elf_entry = (unsigned long) elf_ex.e_entry;
+
+ /* Do this so that we can load the interpreter, if need be. We will
+ change some of these later */
+ info->rss = 0;
+ bprm->p = setup_arg_pages(bprm->p, bprm, info);
+ info->start_stack = bprm->p;
+
+ /* Now we do a little grungy work by mmaping the ELF image into
+ * the correct location in memory. At this point, we assume that
+ * the image should be loaded at fixed address, not at a variable
+ * address.
+ */
+
+
+
+ for(i = 0, elf_ppnt = elf_phdata; i < elf_ex.e_phnum; i++, elf_ppnt++) {
+ if (elf_ppnt->p_type == PT_LOAD) {
+ int elf_prot = 0;
+ if (elf_ppnt->p_flags & PF_R) elf_prot |= PROT_READ;
+ if (elf_ppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
+ if (elf_ppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
+
+ mapped_addr = mmap4k(X86_ELF_PAGESTART(elf_ppnt->p_vaddr),
+ (elf_ppnt->p_filesz +
+ X86_ELF_PAGEOFFSET(elf_ppnt->p_vaddr)),
+ elf_prot,
+ (MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE),
+ bprm->fd,
+ (elf_ppnt->p_offset -
+ X86_ELF_PAGEOFFSET(elf_ppnt->p_vaddr)));
+
+ if((unsigned long)mapped_addr == 0xffffffffffffffff) {
+ perror("mmap");
+ exit(-1);
+ }
+
+
+
+#ifdef LOW_ELF_STACK
+ if (X86_ELF_PAGESTART(elf_ppnt->p_vaddr) < elf_stack)
+ elf_stack = X86_ELF_PAGESTART(elf_ppnt->p_vaddr);
+#endif
+
+ if (!load_addr_set) {
+ load_addr = elf_ppnt->p_vaddr - elf_ppnt->p_offset;
+ load_addr_set = 1;
+ }
+ k = elf_ppnt->p_vaddr;
+ if (k < start_code) start_code = k;
+ k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
+ if (k > elf_bss) elf_bss = k;
+#if 1
+ if ((elf_ppnt->p_flags & PF_X) && end_code < k)
+#else
+ if ( !(elf_ppnt->p_flags & PF_W) && end_code < k)
+#endif
+ end_code = k;
+ if (end_data < k) end_data = k;
+ k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
+ if (k > elf_brk) elf_brk = k;
+ }
+ }
+
+ if (elf_interpreter) {
+ if (interpreter_type & 1) {
+ elf_entry = load_aout_interp(&interp_ex, interpreter_fd);
+ }
+ else if (interpreter_type & 2) {
+ elf_entry = load_elf_interp(&interp_elf_ex, interpreter_fd,
+ &interp_load_addr);
+ }
+
+ close(interpreter_fd);
+ free(elf_interpreter);
+
+ if (elf_entry == ~0UL) {
+ printf("Unable to load interpreter\n");
+ free(elf_phdata);
+ exit(-1);
+ return 0;
+ }
+ }
+
+ free(elf_phdata);
+
+ if (interpreter_type != INTERPRETER_AOUT) close(bprm->fd);
+ info->personality = (ibcs2_interpreter ? PER_SVR4 : PER_LINUX);
+
+#ifdef LOW_ELF_STACK
+ info->start_stack = bprm->p = elf_stack - 4;
+#endif
+ bprm->p = (unsigned long)
+ create_elf_tables((char *)bprm->p,
+ bprm->argc,
+ bprm->envc,
+ (interpreter_type == INTERPRETER_ELF ? &elf_ex : NULL),
+ load_addr,
+ interp_load_addr,
+ (interpreter_type == INTERPRETER_AOUT ? 0 : 1),
+ info);
+ if (interpreter_type == INTERPRETER_AOUT)
+ info->arg_start += strlen(passed_fileno) + 1;
+ info->start_brk = info->brk = elf_brk;
+ info->end_code = end_code;
+ info->start_code = start_code;
+ info->end_data = end_data;
+ info->start_stack = bprm->p;
+
+ /* Calling set_brk effectively mmaps the pages that we need for the bss and break
+ sections */
+ set_brk(elf_bss, elf_brk);
+
+ padzero(elf_bss);
+
+#if 0
+ printf("(start_brk) %x\n" , info->start_brk);
+ printf("(end_code) %x\n" , info->end_code);
+ printf("(start_code) %x\n" , info->start_code);
+ printf("(end_data) %x\n" , info->end_data);
+ printf("(start_stack) %x\n" , info->start_stack);
+ printf("(brk) %x\n" , info->brk);
+#endif
+
+ if ( info->personality == PER_SVR4 )
+ {
+ /* Why this, you ask??? Well SVr4 maps page 0 as read-only,
+ and some applications "depend" upon this behavior.
+ Since we do not have the power to recompile these, we
+ emulate the SVr4 behavior. Sigh. */
+ mapped_addr = mmap4k(NULL, ALPHA_PAGE_SIZE, PROT_READ | PROT_EXEC,
+ MAP_FIXED | MAP_PRIVATE, -1, 0);
+ }
+
+#ifdef ELF_PLAT_INIT
+ /*
+ * The ABI may specify that certain registers be set up in special
+ * ways (on i386 %edx is the address of a DT_FINI function, for
+ * example. This macro performs whatever initialization to
+ * the regs structure is required.
+ */
+ ELF_PLAT_INIT(regs);
+#endif
+
+
+ info->entry = elf_entry;
+
+ return 0;
+}
+
+
+
+int elf_exec(const char * filename, char ** argv, char ** envp,
+ struct pt_regs * regs, struct image_info *infop)
+{
+ struct linux_binprm bprm;
+ int retval;
+ int i;
+
+ bprm.p = X86_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int);
+ for (i=0 ; i<MAX_ARG_PAGES ; i++) /* clear page-table */
+ bprm.page[i] = 0;
+ retval = open(filename, O_RDONLY);
+ if (retval == -1) {
+ perror(filename);
+ exit(-1);
+ /* return retval; */
+ }
+ else {
+ bprm.fd = retval;
+ }
+ bprm.filename = (char *)filename;
+ bprm.sh_bang = 0;
+ bprm.loader = 0;
+ bprm.exec = 0;
+ bprm.dont_iput = 0;
+ bprm.argc = count(argv);
+ bprm.envc = count(envp);
+
+ retval = prepare_binprm(&bprm);
+
+ if(retval>=0) {
+ bprm.p = copy_strings(1, &bprm.filename, bprm.page, bprm.p);
+ bprm.exec = bprm.p;
+ bprm.p = copy_strings(bprm.envc,envp,bprm.page,bprm.p);
+ bprm.p = copy_strings(bprm.argc,argv,bprm.page,bprm.p);
+ if (!bprm.p) {
+ retval = -E2BIG;
+ }
+ }
+
+ if(retval>=0) {
+ retval = load_elf_binary(&bprm,regs,infop);
+ }
+ if(retval>=0) {
+ /* success. Initialize important registers */
+ regs->esp = infop->start_stack;
+ regs->eip = infop->entry;
+ return retval;
+ }
+
+ /* Something went wrong, return the inode and free the argument pages*/
+ for (i=0 ; i<MAX_ARG_PAGES ; i++) {
+ free_page((void *)bprm.page[i]);
+ }
+ return(retval);
+}
+
+
+static int load_aout_interp(void * exptr, int interp_fd)
+{
+ printf("a.out interpreter not yet supported\n");
+ return(0);
+}
+
generated by cgit v1.2.1 (git 2.18.0) at 2024-05-29 23:02:46 +0000