/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1991 NeXT Computer, Inc.  All rights reserved.
 *
 *      File:   bsd/kern/kern_core.c
 *
 *      This file contains machine independent code for performing core dumps.
 *
 */

#include <mach/vm_param.h>
#include <mach/thread_status.h>

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/signalvar.h>
#include <sys/resourcevar.h>
#include <sys/namei.h>
#include <sys/vnode_internal.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/timeb.h>
#include <sys/times.h>
#include <sys/acct.h>
#include <sys/file_internal.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/stat.h>

#include <mach-o/loader.h>
#include <mach/vm_region.h>
#include <mach/vm_statistics.h>

#include <vm/vm_kern.h>
#include <vm/vm_protos.h> /* last */
#include <vm/vm_map.h>          /* current_map() */
#include <mach/mach_vm.h>       /* mach_vm_region_recurse() */
#include <mach/task.h>          /* task_suspend() */
#include <kern/task.h>          /* get_task_numacts() */

typedef struct {
        int     flavor;                 /* the number for this flavor */
        int     count;                  /* count of ints in this flavor */
} mythread_state_flavor_t;

#if defined (__ppc__)

mythread_state_flavor_t thread_flavor_array[]={
                {PPC_THREAD_STATE , PPC_THREAD_STATE_COUNT},
                {PPC_FLOAT_STATE, PPC_FLOAT_STATE_COUNT}, 
                {PPC_EXCEPTION_STATE, PPC_EXCEPTION_STATE_COUNT},
                {PPC_VECTOR_STATE, PPC_VECTOR_STATE_COUNT}
                };
int mynum_flavors=4;
#elif defined (__i386__)
mythread_state_flavor_t thread_flavor_array [] = { 
                {i386_THREAD_STATE, i386_THREAD_STATE_COUNT},
                {i386_THREAD_FPSTATE, i386_THREAD_FPSTATE_COUNT},
                {i386_THREAD_EXCEPTSTATE, i386_THREAD_EXCEPTSTATE_COUNT},
                {i386_THREAD_CTHREADSTATE, i386_THREAD_CTHREADSTATE_COUNT},
                {i386_NEW_THREAD_STATE, i386_NEW_THREAD_STATE_COUNT},
                {i386_FLOAT_STATE, i386_FLOAT_STATE_COUNT},
                {i386_ISA_PORT_MAP_STATE, i386_ISA_PORT_MAP_STATE_COUNT},
                {i386_V86_ASSIST_STATE, i386_V86_ASSIST_STATE_COUNT},
                {THREAD_SYSCALL_STATE, i386_THREAD_SYSCALL_STATE_COUNT}
                };
int mynum_flavors=9;

#else
#error architecture not supported
#endif


typedef struct {
        vm_offset_t header; 
        int  hoffset;
        mythread_state_flavor_t *flavors;
        int tstate_size;
} tir_t;

/* XXX should be static */
void collectth_state(thread_t th_act, void *tirp);

/* XXX not in a Mach header anywhere */
kern_return_t thread_getstatus(register thread_t act, int flavor,
        thread_state_t tstate, mach_msg_type_number_t *count);
void task_act_iterate_wth_args(task_t, void(*)(thread_t, void *), void *);


__private_extern__ int do_coredump = 1; /* default: dump cores */
__private_extern__ int sugid_coredump = 0; /* default: but not SGUID binaries */

void
collectth_state(thread_t th_act, void *tirp)
{
        vm_offset_t     header;
        int  hoffset, i ;
        mythread_state_flavor_t *flavors;
        struct thread_command   *tc;
        tir_t *t = (tir_t *)tirp;

                /*
                 *      Fill in thread command structure.
                 */
                header = t->header;
                hoffset = t->hoffset;
                flavors = t->flavors;
        
                tc = (struct thread_command *) (header + hoffset);
                tc->cmd = LC_THREAD;
                tc->cmdsize = sizeof(struct thread_command)
                                + t->tstate_size;
                hoffset += sizeof(struct thread_command);
                /*
                 * Follow with a struct thread_state_flavor and
                 * the appropriate thread state struct for each
                 * thread state flavor.
                 */
                for (i = 0; i < mynum_flavors; i++) {
                        *(mythread_state_flavor_t *)(header+hoffset) =
                          flavors[i];
                        hoffset += sizeof(mythread_state_flavor_t);
                        thread_getstatus(th_act, flavors[i].flavor,
                                        (thread_state_t)(header+hoffset),
                                        &flavors[i].count);
                        hoffset += flavors[i].count*sizeof(int);
                }

                t->hoffset = hoffset;
}

/*
 * Create a core image on the file "core".
 */
#define MAX_TSTATE_FLAVORS      10
int
coredump(struct proc *p)
{
        int error=0;
        kauth_cred_t cred = kauth_cred_get();
        struct vnode_attr va;
        struct vfs_context context;
        vm_map_t        map;
        int             thread_count, segment_count;
        int             command_size, header_size, tstate_size;
        int             hoffset;
        off_t           foffset;
        vm_map_offset_t vmoffset;
        vm_offset_t     header;
        vm_map_size_t   vmsize;
        vm_prot_t       prot;
        vm_prot_t       maxprot;
        vm_inherit_t    inherit;
        int             error1;
        task_t          task;
        char            core_name[MAXCOMLEN+6];
        char            *name;
        mythread_state_flavor_t flavors[MAX_TSTATE_FLAVORS];
        vm_size_t       mapsize;
        int             i;
        int nesting_depth = 0;
        kern_return_t   kret;
        struct vm_region_submap_info_64 vbr;
        int vbrcount=0;
        tir_t tir1;
        struct vnode * vp;
        struct mach_header      *mh;
        struct mach_header_64   *mh64;
        int             is_64 = 0;
        size_t          mach_header_sz = sizeof(struct mach_header);
        size_t          segment_command_sz = sizeof(struct segment_command);

        if (do_coredump == 0 ||         /* Not dumping at all */
            ( (sugid_coredump == 0) &&  /* Not dumping SUID/SGID binaries */
              ( (cred->cr_svuid != cred->cr_ruid) ||
                (cred->cr_svgid != cred->cr_rgid)))) {
            
                return (EFAULT);
        }

        if (IS_64BIT_PROCESS(p)) {
                is_64 = 1;
                mach_header_sz = sizeof(struct mach_header_64);
                segment_command_sz = sizeof(struct segment_command_64);
        }

        task = current_task();
        map = current_map();
        mapsize = get_vmmap_size(map);

        if (mapsize >=  p->p_rlimit[RLIMIT_CORE].rlim_cur)
                return (EFAULT);
        (void) task_suspend(task);

        /* create name according to sysctl'able format string */
        name = proc_core_name(p->p_comm, kauth_cred_getuid(cred), p->p_pid);

        /* if name creation fails, fall back to historical behaviour... */
        if (name == NULL) {
                sprintf(core_name, "/cores/core.%d", p->p_pid);
                name = core_name;
        }
        context.vc_proc = p;
        context.vc_ucred = cred;

        if ((error = vnode_open(name, (O_CREAT | FWRITE | O_NOFOLLOW), S_IRUSR, VNODE_LOOKUP_NOFOLLOW, &vp, &context)))
                return (error);

        VATTR_INIT(&va);
        VATTR_WANTED(&va, va_nlink);
        /* Don't dump to non-regular files or files with links. */
        if (vp->v_type != VREG ||
            vnode_getattr(vp, &va, &context) || va.va_nlink != 1) {
                error = EFAULT;
                goto out;
        }

        VATTR_INIT(&va);        /* better to do it here than waste more stack in vnode_setsize */
        VATTR_SET(&va, va_data_size, 0);
        vnode_setattr(vp, &va, &context);
        p->p_acflag |= ACORE;

        /*
         *      If the task is modified while dumping the file
         *      (e.g., changes in threads or VM, the resulting
         *      file will not necessarily be correct.
         */

        thread_count = get_task_numacts(task);
        segment_count = get_vmmap_entries(map); /* XXX */
        bcopy(thread_flavor_array,flavors,sizeof(thread_flavor_array));
        tstate_size = 0;
        for (i = 0; i < mynum_flavors; i++)
                tstate_size += sizeof(mythread_state_flavor_t) +
                  (flavors[i].count * sizeof(int));

        command_size = segment_count * segment_command_sz +
          thread_count*sizeof(struct thread_command) +
          tstate_size*thread_count;

        header_size = command_size + mach_header_sz;

        (void) kmem_alloc(kernel_map,
                                    (vm_offset_t *)&header,
                                    (vm_size_t)header_size);

        /*
         *      Set up Mach-O header.
         */
        if (is_64) {
                mh64 = (struct mach_header_64 *)header;
                mh64->magic = MH_MAGIC_64;
                mh64->cputype = cpu_type();
                mh64->cpusubtype = cpu_subtype();
                mh64->filetype = MH_CORE;
                mh64->ncmds = segment_count + thread_count;
                mh64->sizeofcmds = command_size;
                mh64->reserved = 0;             /* 8 byte alignment */
        } else {
                mh = (struct mach_header *)header;
                mh->magic = MH_MAGIC;
                mh->cputype = cpu_type();
                mh->cpusubtype = cpu_subtype();
                mh->filetype = MH_CORE;
                mh->ncmds = segment_count + thread_count;
                mh->sizeofcmds = command_size;
        }

        hoffset = mach_header_sz;       /* offset into header */
        foffset = round_page(header_size);      /* offset into file */
        vmoffset = MACH_VM_MIN_ADDRESS;         /* offset into VM */

        /*
         * We use to check for an error, here, now we try and get 
         * as much as we can
         */
        while (segment_count > 0) {
                struct segment_command          *sc;
                struct segment_command_64       *sc64;

                /*
                 *      Get region information for next region.
                 */
                
                while (1) {
                        vbrcount = VM_REGION_SUBMAP_INFO_COUNT_64;
                        if((kret = mach_vm_region_recurse(map, 
                                        &vmoffset, &vmsize, &nesting_depth, 
                                        (vm_region_recurse_info_t)&vbr,
                                        &vbrcount)) != KERN_SUCCESS) {
                                break;
                        }
                        /*
                         * If we get a valid mapping back, but we're dumping
                         * a 32 bit process,  and it's over the allowable
                         * address space of a 32 bit process, it's the same
                         * as if mach_vm_region_recurse() failed.
                         */
                        if (!(is_64) &&
                            (vmoffset + vmsize > VM_MAX_ADDRESS)) {
                                kret = KERN_INVALID_ADDRESS;
                                break;
                        }
                        if(vbr.is_submap) {
                                nesting_depth++;
                                continue;
                        } else {
                                break;
                        }
                }
                if(kret != KERN_SUCCESS)
                        break;

                prot = vbr.protection;
                maxprot = vbr.max_protection;
                inherit = vbr.inheritance;
                /*
                 *      Fill in segment command structure.
                 */
                if (is_64) {
                        sc64 = (struct segment_command_64 *)(header + hoffset);
                        sc64->cmd = LC_SEGMENT_64;
                        sc64->cmdsize = sizeof(struct segment_command_64);
                        /* segment name is zeroed by kmem_alloc */
                        sc64->segname[0] = 0;
                        sc64->vmaddr = vmoffset;
                        sc64->vmsize = vmsize;
                        sc64->fileoff = foffset;
                        sc64->filesize = vmsize;
                        sc64->maxprot = maxprot;
                        sc64->initprot = prot;
                        sc64->nsects = 0;
                } else  {
                        sc = (struct segment_command *) (header + hoffset);
                        sc->cmd = LC_SEGMENT;
                        sc->cmdsize = sizeof(struct segment_command);
                        /* segment name is zeroed by kmem_alloc */
                        sc->segname[0] = 0;
                        sc->vmaddr = CAST_DOWN(vm_offset_t,vmoffset);
                        sc->vmsize = CAST_DOWN(vm_size_t,vmsize);
                        sc->fileoff = CAST_DOWN(uint32_t,foffset);
                        sc->filesize = CAST_DOWN(uint32_t,vmsize);
                        sc->maxprot = maxprot;
                        sc->initprot = prot;
                        sc->nsects = 0;
                }

                /*
                 *      Write segment out.  Try as hard as possible to
                 *      get read access to the data.
                 */
                if ((prot & VM_PROT_READ) == 0) {
                        mach_vm_protect(map, vmoffset, vmsize, FALSE,
                                           prot|VM_PROT_READ);
                }
                /*
                 *      Only actually perform write if we can read.
                 *      Note: if we can't read, then we end up with
                 *      a hole in the file.
                 */
                if ((maxprot & VM_PROT_READ) == VM_PROT_READ
                        && vbr.user_tag != VM_MEMORY_IOKIT
                        && coredumpok(map,vmoffset)) {
                        vm_map_size_t   tmp_vmsize = vmsize;
                        off_t           xfer_foffset = foffset;

                        //LP64todo - works around vn_rdwr_64() 2G limit
                        while (tmp_vmsize > 0) {
                                vm_map_size_t   xfer_vmsize = tmp_vmsize;
                                if (xfer_vmsize > INT_MAX)
                                        xfer_vmsize = INT_MAX;
                                error = vn_rdwr_64(UIO_WRITE, vp,
                                                vmoffset, xfer_vmsize, xfer_foffset,
                                        (IS_64BIT_PROCESS(p) ? UIO_USERSPACE64 : UIO_USERSPACE32), 
                                        IO_NODELOCKED|IO_UNIT, cred, (int *) 0, p);
                                tmp_vmsize -= xfer_vmsize;
                                xfer_foffset += xfer_vmsize;
                        }
                }

                hoffset += segment_command_sz;
                foffset += vmsize;
                vmoffset += vmsize;
                segment_count--;
        }

        /*
         * If there are remaining segments which have not been written
         * out because break in the loop above, then they were not counted
         * because they exceed the real address space of the executable
         * type: remove them from the header's count.  This is OK, since
         * we are allowed to have a sparse area following the segments.
         */
        if (is_64) {
                mh64->ncmds -= segment_count;
        } else {
                mh->ncmds -= segment_count;
        }

        tir1.header = header;
        tir1.hoffset = hoffset;
        tir1.flavors = flavors;
        tir1.tstate_size = tstate_size;
        task_act_iterate_wth_args(task, collectth_state,&tir1);

        /*
         *      Write out the Mach header at the beginning of the
         *      file.  OK to use a 32 bit write for this.
         */
        error = vn_rdwr(UIO_WRITE, vp, (caddr_t)header, header_size, (off_t)0,
                        UIO_SYSSPACE32, IO_NODELOCKED|IO_UNIT, cred, (int *) 0, p);
        kmem_free(kernel_map, header, header_size);
out:
        error1 = vnode_close(vp, FWRITE, &context);
        if (error == 0)
                error = error1;

        return (error);
}