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/*

 *  linux/fs/binfmt_aout.c

 *

 *  Copyright (C) 1991, 1992, 1996  Linus Torvalds

 */

#include <linux/module.h>

#include <linux/fs.h>

#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/mm.h>

#include <linux/mman.h>

#include <linux/a.out.h>

#include <linux/errno.h>

#include <linux/signal.h>

#include <linux/string.h>

#include <linux/stat.h>

#include <linux/fcntl.h>

#include <linux/ptrace.h>

#include <linux/user.h>

#include <linux/malloc.h>

#include <linux/binfmts.h>

#include <linux/personality.h>

#include <asm/system.h>

#include <asm/segment.h>

#include <asm/pgtable.h>

static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs);

static int load_aout_library(int fd);

static int aout_core_dump(long signr, struct pt_regs * regs);

extern void dump_thread(struct pt_regs *, struct user *);

static struct linux_binfmt aout_format = {

#ifndef MODULE

        NULL, NULL, load_aout_binary, load_aout_library, aout_core_dump

#else

        NULL, &mod_use_count_, load_aout_binary, load_aout_library, aout_core_dump

#endif

};

static void set_brk(unsigned long start, unsigned long end)

{

        start = PAGE_ALIGN(start);

        end = PAGE_ALIGN(end);

        if (end <= start)

                return;

        do_mmap(NULL, start, end - start,

                PROT_READ | PROT_WRITE | PROT_EXEC,

                MAP_FIXED | MAP_PRIVATE, 0);

}

/*

 * These are the only things you should do on a core-file: use only these

 * macros to write out all the necessary info.

 */

#define DUMP_WRITE(addr,nr) \

while (file.f_op->write(inode,&file,(char *)(addr),(nr)) != (nr)) goto close_coredump

#define DUMP_SEEK(offset) \

if (file.f_op->lseek) { \

        if (file.f_op->lseek(inode,&file,(offset),0) != (offset)) \

                goto close_coredump; \

} else file.f_pos = (offset)

/*

 * Routine writes a core dump image in the current directory.

 * Currently only a stub-function.

 *

 * Note that setuid/setgid files won't make a core-dump if the uid/gid

 * changed due to the set[u|g]id. It's enforced by the "current->dumpable"

 * field, which also makes sure the core-dumps won't be recursive if the

 * dumping of the process results in another error..

 */

static inline int

do_aout_core_dump(long signr, struct pt_regs * regs)

{

        struct inode * inode = NULL;

        struct file file;

        unsigned short fs;

        int has_dumped = 0;

        char corefile[6+sizeof(current->comm)];

        unsigned long dump_start, dump_size;

        struct user dump;

#ifdef __alpha__

#       define START_DATA(u)    (u.start_data)

#elif defined(CONFIG_ARM)

#       define START_DATA(u)    ((u.u_tsize << PAGE_SHIFT) + u.start_code)

#else

#       define START_DATA(u)    (u.u_tsize << PAGE_SHIFT)

#endif

        if (!current->dumpable || current->mm->count != 1)

                return 0;

        current->dumpable = 0;

/* See if we have enough room to write the upage.  */

        if (current->rlim[RLIMIT_CORE].rlim_cur < PAGE_SIZE)

                return 0;

        fs = get_fs();

        set_fs(KERNEL_DS);

        memcpy(corefile,"core.",5);

#if 0

        memcpy(corefile+5,current->comm,sizeof(current->comm));

#else

        corefile[4] = '\0';

#endif

        if (open_namei(corefile,O_CREAT | 2 | O_TRUNC,0600,&inode,NULL)) {

                inode = NULL;

                goto end_coredump;

        }

        if (!S_ISREG(inode->i_mode))

                goto end_coredump;

        if (!inode->i_op || !inode->i_op->default_file_ops)

                goto end_coredump;

        if (get_write_access(inode))

                goto end_coredump;

        file.f_mode = 3;

        file.f_flags = 0;

        file.f_count = 1;

        file.f_inode = inode;

        file.f_pos = 0;

        file.f_reada = 0;

        file.f_op = inode->i_op->default_file_ops;

        if (file.f_op->open)

                if (file.f_op->open(inode,&file))

                        goto done_coredump;

        if (!file.f_op->write)

                goto close_coredump;

        has_dumped = 1;

        current->flags |= PF_DUMPCORE;

        strncpy(dump.u_comm, current->comm, sizeof(current->comm));

        dump.u_ar0 = (void *)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump)));

        dump.signal = signr;

        dump_thread(regs, &dump);

/* If the size of the dump file exceeds the rlimit, then see what would happen

   if we wrote the stack, but not the data area.  */

        if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE >

            current->rlim[RLIMIT_CORE].rlim_cur)

                dump.u_dsize = 0;

/* Make sure we have enough room to write the stack and data areas. */

        if ((dump.u_ssize+1) * PAGE_SIZE >

            current->rlim[RLIMIT_CORE].rlim_cur)

                dump.u_ssize = 0;

/* make sure we actually have a data and stack area to dump */

        set_fs(USER_DS);

        if (verify_area(VERIFY_READ, (void *) START_DATA(dump), dump.u_dsize << PAGE_SHIFT))

                dump.u_dsize = 0;

        if (verify_area(VERIFY_READ, (void *) dump.start_stack, dump.u_ssize << PAGE_SHIFT))

                dump.u_ssize = 0;

        set_fs(KERNEL_DS);

/* struct user */

        DUMP_WRITE(&dump,sizeof(dump));

/* Now dump all of the user data.  Include malloced stuff as well */

        DUMP_SEEK(PAGE_SIZE);

/* now we start writing out the user space info */

        set_fs(USER_DS);

/* Dump the data area */

        if (dump.u_dsize != 0) {

                dump_start = START_DATA(dump);

                dump_size = dump.u_dsize << PAGE_SHIFT;

                DUMP_WRITE(dump_start,dump_size);

        }

/* Now prepare to dump the stack area */

        if (dump.u_ssize != 0) {

                dump_start = dump.start_stack;

                dump_size = dump.u_ssize << PAGE_SHIFT;

                DUMP_WRITE(dump_start,dump_size);

        }

/* Finally dump the task struct.  Not be used by gdb, but could be useful */

        set_fs(KERNEL_DS);

        DUMP_WRITE(current,sizeof(*current));

close_coredump:

        if (file.f_op->release)

                file.f_op->release(inode,&file);

done_coredump:

        put_write_access(inode);

end_coredump:

        set_fs(fs);

        iput(inode);

        return has_dumped;

}

static int

aout_core_dump(long signr, struct pt_regs * regs)

{

        int retval;

        MOD_INC_USE_COUNT;

        retval = do_aout_core_dump(signr, regs);

        MOD_DEC_USE_COUNT;

        return retval;

}

/*

 * create_aout_tables() parses the env- and arg-strings in new user

 * memory and creates the pointer tables from them, and puts their

 * addresses on the "stack", returning the new stack pointer value.

 */

static unsigned long * create_aout_tables(char * p, struct linux_binprm * bprm)

{

        unsigned long *argv,*envp;

        unsigned long * sp;

        int argc = bprm->argc;

        int envc = bprm->envc;

        sp = (unsigned long *) ((-(unsigned long)sizeof(char *)) & (unsigned long) p);

#ifdef __alpha__

/* whee.. test-programs are so much fun. */

        put_user(0, --sp);

        put_user(0, --sp);

        if (bprm->loader) {

                put_user(0, --sp);

                put_user(0x3eb, --sp);

                put_user(bprm->loader, --sp);

                put_user(0x3ea, --sp);

        }

        put_user(bprm->exec, --sp);

        put_user(0x3e9, --sp);

#endif

        sp -= envc+1;

        envp = sp;

        sp -= argc+1;

        argv = sp;

#if defined(__i386__) || defined(__mc68000__) || defined(CONFIG_ARM)

        put_user(envp,--sp);

        put_user(argv,--sp);

#endif

        put_user(argc,--sp);

        current->mm->arg_start = (unsigned long) p;

        while (argc-->0) {

                put_user(p,argv++);

                while (get_user(p++)) /* nothing */ ;

        }

        put_user(NULL,argv);

        current->mm->arg_end = current->mm->env_start = (unsigned long) p;

        while (envc-->0) {

                put_user(p,envp++);

                while (get_user(p++)) /* nothing */ ;

        }

        put_user(NULL,envp);

        current->mm->env_end = (unsigned long) p;

        return sp;

}

/*

 * These are the functions used to load a.out style executables and shared

 * libraries.  There is no binary dependent code anywhere else.

 */

static inline int

do_load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)

{

        struct exec ex;

        struct file * file;

        int fd;

        unsigned long error;

        unsigned long p = bprm->p;

        unsigned long fd_offset;

        unsigned long rlim;

        ex = *((struct exec *) bprm->buf);              /* exec-header */

        if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC &&

             N_MAGIC(ex) != QMAGIC) ||

            N_TRSIZE(ex) || N_DRSIZE(ex) ||

            bprm->inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {

                return -ENOEXEC;

        }

        current->personality = PER_LINUX;

        fd_offset = N_TXTOFF(ex);

#if defined (__i386__) || defined (CONFIG_ARM)

        if (N_MAGIC(ex) == ZMAGIC && fd_offset != BLOCK_SIZE) {

                printk(KERN_NOTICE "N_TXTOFF != BLOCK_SIZE. See a.out.h.\n");

                return -ENOEXEC;

        }

        if (N_MAGIC(ex) == ZMAGIC && ex.a_text &&

            (fd_offset < bprm->inode->i_sb->s_blocksize)) {

                printk(KERN_NOTICE "N_TXTOFF < BLOCK_SIZE. Please convert binary.\n");

                return -ENOEXEC;

        }

#endif

#if defined(CONFIG_ARM)

        if (N_MACHTYPE(ex) != M_ARM) {

                printk(KERN_NOTICE "Binary != ARM.  Please recompile binary.\n");

                return -ENOEXEC;

        }

#endif

        /* Check initial limits. This avoids letting people circumvent

         * size limits imposed on them by creating programs with large

         * arrays in the data or bss.

         */

        rlim = current->rlim[RLIMIT_DATA].rlim_cur;

        if (rlim >= RLIM_INFINITY)

                rlim = ~0;

        if (ex.a_data + ex.a_bss > rlim)

                return -ENOMEM;

        if (flush_old_exec(bprm))

                return -ENOMEM;

        /* OK, This is the point of no return */

        current->mm->end_code = ex.a_text +

                (current->mm->start_code = N_TXTADDR(ex));

        current->mm->end_data = ex.a_data +

                (current->mm->start_data = N_DATADDR(ex));

        current->mm->brk = ex.a_bss +

                (current->mm->start_brk = N_BSSADDR(ex));

        current->mm->rss = 0;

        current->mm->mmap = NULL;

        current->suid = current->euid = current->fsuid = bprm->e_uid;

        current->sgid = current->egid = current->fsgid = bprm->e_gid;

        current->flags &= ~PF_FORKNOEXEC;

        if (N_MAGIC(ex) == OMAGIC) {

#if defined(__alpha__) || defined(CONFIG_ARM)

#ifndef CONFIG_ARM

                do_mmap(NULL, N_TXTADDR(ex) & PAGE_MASK,

                        ex.a_text+ex.a_data + PAGE_SIZE - 1,

                        PROT_READ|PROT_WRITE|PROT_EXEC,

                        MAP_FIXED|MAP_PRIVATE, 0);

#else

                do_mmap(NULL, N_TXTADDR(ex),

                        ex.a_text+ex.a_data,

                        PROT_READ|PROT_WRITE|PROT_EXEC,

                        MAP_FIXED|MAP_PRIVATE, 0);

#endif

                read_exec(bprm->inode, fd_offset, (char *) N_TXTADDR(ex),

                          ex.a_text+ex.a_data, 0);

#else

                do_mmap(NULL, 0, ex.a_text+ex.a_data,

                        PROT_READ|PROT_WRITE|PROT_EXEC,

                        MAP_FIXED|MAP_PRIVATE, 0);

                read_exec(bprm->inode, 32, (char *) 0, ex.a_text+ex.a_data, 0);

#endif

        } else {

                if (ex.a_text & 0xfff || ex.a_data & 0xfff)

                        printk(KERN_NOTICE "executable not page aligned\n");

                fd = open_inode(bprm->inode, O_RDONLY);

                if (fd < 0) {

                        send_sig(SIGKILL, current, 0);

                        return fd;

                }

                file = current->files->fd[fd];

                if (!file->f_op || !file->f_op->mmap) {

                        sys_close(fd);

                        do_mmap(NULL, 0, ex.a_text+ex.a_data,

                                PROT_READ|PROT_WRITE|PROT_EXEC,

                                MAP_FIXED|MAP_PRIVATE, 0);

                        read_exec(bprm->inode, fd_offset,

                                  (char *) N_TXTADDR(ex), ex.a_text+ex.a_data, 0);

                        goto beyond_if;

                }

                error = do_mmap(file, N_TXTADDR(ex), ex.a_text,

                        PROT_READ | PROT_EXEC,

                        MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,

                        fd_offset);

                if (error != N_TXTADDR(ex)) {

                        sys_close(fd);

                        send_sig(SIGKILL, current, 0);

                        return error;

                }

                error = do_mmap(file, N_DATADDR(ex), ex.a_data,

                                PROT_READ | PROT_WRITE | PROT_EXEC,

                                MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE,

                                fd_offset + ex.a_text);

                sys_close(fd);

                if (error != N_DATADDR(ex)) {

                        send_sig(SIGKILL, current, 0);

                        return error;

                }

        }

beyond_if:

        if (current->exec_domain && current->exec_domain->use_count)

                (*current->exec_domain->use_count)--;

        if (current->binfmt && current->binfmt->use_count)

                (*current->binfmt->use_count)--;

        current->exec_domain = lookup_exec_domain(current->personality);

        current->binfmt = &aout_format;

        if (current->exec_domain && current->exec_domain->use_count)

                (*current->exec_domain->use_count)++;

        if (current->binfmt && current->binfmt->use_count)

                (*current->binfmt->use_count)++;

        set_brk(current->mm->start_brk, current->mm->brk);

        p = setup_arg_pages(p, bprm);

        p = (unsigned long) create_aout_tables((char *)p, bprm);

        current->mm->start_stack = p;

#ifdef __alpha__

        regs->gp = ex.a_gpvalue;

#endif

        start_thread(regs, ex.a_entry, p);

        if (current->flags & PF_PTRACED)

                send_sig(SIGTRAP, current, 0);

#ifndef CONFIG_ARM

        return 0;

#else

        return regs->ARM_r0;

#endif

}

static int

load_aout_binary(struct linux_binprm * bprm, struct pt_regs * regs)

{

        int retval;

        MOD_INC_USE_COUNT;

        retval = do_load_aout_binary(bprm, regs);

        MOD_DEC_USE_COUNT;

        return retval;

}

static inline int

do_load_aout_library(int fd)

{

        struct file * file;

        struct exec ex;

        struct  inode * inode;

        unsigned int len;

        unsigned int bss;

        unsigned int start_addr;

        unsigned long error;

        file = current->files->fd[fd];

        inode = file->f_inode;

        if (!file || !file->f_op)

                return -EACCES;

        /* Seek into the file */

        if (file->f_op->lseek) {

                if ((error = file->f_op->lseek(inode, file, 0, 0)) != 0)

                        return -ENOEXEC;

        } else

                file->f_pos = 0;

        set_fs(KERNEL_DS);

        error = file->f_op->read(inode, file, (char *) &ex, sizeof(ex));

        set_fs(USER_DS);

        if (error != sizeof(ex))

                return -ENOEXEC;

        /* We come in here for the regular a.out style of shared libraries */

        if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) ||

            N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) ||

            inode->i_size < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {

                return -ENOEXEC;

        }

        if (N_MAGIC(ex) == ZMAGIC && N_TXTOFF(ex) &&

            (N_TXTOFF(ex) < inode->i_sb->s_blocksize)) {

                printk("N_TXTOFF < BLOCK_SIZE. Please convert library\n");

                return -ENOEXEC;

        }

        if (N_FLAGS(ex)) return -ENOEXEC;

        /* For  QMAGIC, the starting address is 0x20 into the page.  We mask

           this off to get the starting address for the page */

#ifndef CONFIG_ARM

        start_addr =  ex.a_entry & 0xfffff000;

        /* Now use mmap to map the library into memory. */

        error = do_mmap(file, start_addr, ex.a_text + ex.a_data,

                        PROT_READ | PROT_WRITE | PROT_EXEC,

                        MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,

                        N_TXTOFF(ex));

        if (error != start_addr)

                return error;

        len = PAGE_ALIGN(ex.a_text + ex.a_data);

        bss = ex.a_text + ex.a_data + ex.a_bss;

#else

        start_addr = ex.a_entry & 0xffff8000;

        {

                unsigned int offset;

                unsigned int length;

                switch (N_MAGIC(ex)) {

                case QMAGIC:

                        offset = 0;

                        length = ex.a_text + ex.a_data;

                        break;

                case ZMAGIC: /* or QMAGIC */

                        offset = N_TXTOFF(ex);

                        length = ex.a_text + ex.a_data;

                        break;

                default:

                        return -ENOEXEC;

                }

                /* Now use mmap to map the library into memory. */

                error = do_mmap(file, start_addr, length,

                                PROT_READ | PROT_WRITE | PROT_EXEC,

                                MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE,

                                offset);

                if (error != start_addr)

                        return error;

                len = PAGE_ALIGN(length);

                bss = length + ex.a_bss;

        }

#endif

        if (bss > len) {

                error = do_mmap(NULL, start_addr + len, bss-len,

                                PROT_READ|PROT_WRITE|PROT_EXEC,

                                MAP_PRIVATE|MAP_FIXED, 0);

                if (error != start_addr + len)

                        return error;

        }

        return 0;

}

static int

load_aout_library(int fd)

{

        int retval;

        MOD_INC_USE_COUNT;

        retval = do_load_aout_library(fd);

        MOD_DEC_USE_COUNT;

        return retval;

}

int init_aout_binfmt(void) {

        return register_binfmt(&aout_format);

}

#ifdef MODULE

int init_module(void) {

        return init_aout_binfmt();

}

void cleanup_module( void) {

        unregister_binfmt(&aout_format);

}

#endif