subr_module.c

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/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 1998 Michael Smith
 * All rights reserved.
 * Copyright (c) 2020 NetApp Inc.
 * Copyright (c) 2020 Klara Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
 
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
 
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/linker.h>
#include <sys/sbuf.h>
#include <sys/sysctl.h>
 
#include <machine/metadata.h>
 
#include <vm/vm.h>
#include <vm/vm_extern.h>
 
/*
 * Preloaded module support
 */
 
vm_offset_t preload_addr_relocate = 0;
caddr_t preload_metadata;
 
/*
 * Search for the preloaded module (name)
 */
caddr_t
preload_search_by_name(const char *name)
{
    caddr_t     curp;
    uint32_t    *hdr;
    int         next;
    
    if (preload_metadata != NULL) {
        curp = preload_metadata;
        for (;;) {
            hdr = (uint32_t *)curp;
            if (hdr[0] == 0 && hdr[1] == 0)
                break;
 
            /* Search for a MODINFO_NAME field */
            if ((hdr[0] == MODINFO_NAME) &&
                !strcmp(name, curp + sizeof(uint32_t) * 2))
                return(curp);
 
            /* skip to next field */
            next = sizeof(uint32_t) * 2 + hdr[1];
            next = roundup(next, sizeof(u_long));
            curp += next;
        }
    }
    return(NULL);
}
 
/*
 * Search for the first preloaded module of (type)
 */
caddr_t
preload_search_by_type(const char *type)
{
    caddr_t     curp, lname;
    uint32_t    *hdr;
    int         next;
 
    if (preload_metadata != NULL) {
        curp = preload_metadata;
        lname = NULL;
        for (;;) {
            hdr = (uint32_t *)curp;
            if (hdr[0] == 0 && hdr[1] == 0)
                break;
 
            /* remember the start of each record */
            if (hdr[0] == MODINFO_NAME)
                lname = curp;
 
            /* Search for a MODINFO_TYPE field */
            if ((hdr[0] == MODINFO_TYPE) &&
                !strcmp(type, curp + sizeof(uint32_t) * 2))
                return(lname);
 
            /* skip to next field */
            next = sizeof(uint32_t) * 2 + hdr[1];
            next = roundup(next, sizeof(u_long));
            curp += next;
        }
    }
    return(NULL);
}
 
/*
 * Walk through the preloaded module list
 */
caddr_t
preload_search_next_name(caddr_t base)
{
    caddr_t     curp;
    uint32_t    *hdr;
    int         next;
    
    if (preload_metadata != NULL) {
        /* Pick up where we left off last time */
        if (base) {
            /* skip to next field */
            curp = base;
            hdr = (uint32_t *)curp;
            next = sizeof(uint32_t) * 2 + hdr[1];
            next = roundup(next, sizeof(u_long));
            curp += next;
        } else
            curp = preload_metadata;
 
        for (;;) {
            hdr = (uint32_t *)curp;
            if (hdr[0] == 0 && hdr[1] == 0)
                break;
 
            /* Found a new record? */
            if (hdr[0] == MODINFO_NAME)
                return curp;
 
            /* skip to next field */
            next = sizeof(uint32_t) * 2 + hdr[1];
            next = roundup(next, sizeof(u_long));
            curp += next;
        }
    }
    return(NULL);
}
 
/*
 * Given a preloaded module handle (mod), return a pointer
 * to the data for the attribute (inf).
 */
caddr_t
preload_search_info(caddr_t mod, int inf)
{
    caddr_t     curp;
    uint32_t    *hdr;
    uint32_t    type = 0;
    int         next;
 
    if (mod == NULL)
        return (NULL);
 
    curp = mod;
    for (;;) {
        hdr = (uint32_t *)curp;
        /* end of module data? */
        if (hdr[0] == 0 && hdr[1] == 0)
            break;
        /* 
         * We give up once we've looped back to what we were looking at 
         * first - this should normally be a MODINFO_NAME field.
         */
        if (type == 0) {
            type = hdr[0];
        } else {
            if (hdr[0] == type)
                break;
        }
 
        /* 
         * Attribute match? Return pointer to data.
         * Consumer may safely assume that size value precedes  
         * data.
         */
        if (hdr[0] == inf)
            return(curp + (sizeof(uint32_t) * 2));
 
        /* skip to next field */
        next = sizeof(uint32_t) * 2 + hdr[1];
        next = roundup(next, sizeof(u_long));
        curp += next;
    }
    return(NULL);
}
 
/*
 * Delete a preload record by name.
 */
void
preload_delete_name(const char *name)
{
    caddr_t     addr, curp;
    uint32_t    *hdr, sz;
    int         next;
    int         clearing;
 
    addr = 0;
    sz = 0;
    
    if (preload_metadata != NULL) {
        clearing = 0;
        curp = preload_metadata;
        for (;;) {
            hdr = (uint32_t *)curp;
            if (hdr[0] == MODINFO_NAME || (hdr[0] == 0 && hdr[1] == 0)) {
                /* Free memory used to store the file. */
                if (addr != 0 && sz != 0)
                    kmem_bootstrap_free((vm_offset_t)addr, sz);
                addr = 0;
                sz = 0;
 
                if (hdr[0] == 0)
                    break;
                if (!strcmp(name, curp + sizeof(uint32_t) * 2))
                    clearing = 1;       /* got it, start clearing */
                else if (clearing) {
                    clearing = 0;       /* at next one now.. better stop */
                }
            }
            if (clearing) {
                if (hdr[0] == MODINFO_ADDR)
                    addr = *(caddr_t *)(curp + sizeof(uint32_t) * 2);
                else if (hdr[0] == MODINFO_SIZE)
                    sz = *(uint32_t *)(curp + sizeof(uint32_t) * 2);
                hdr[0] = MODINFO_EMPTY;
            }
 
            /* skip to next field */
            next = sizeof(uint32_t) * 2 + hdr[1];
            next = roundup(next, sizeof(u_long));
            curp += next;
        }
    }
}
 
void *
preload_fetch_addr(caddr_t mod)
{
        caddr_t *mdp;
 
        mdp = (caddr_t *)preload_search_info(mod, MODINFO_ADDR);
        if (mdp == NULL)
                return (NULL);
        return (*mdp + preload_addr_relocate);
}
 
size_t
preload_fetch_size(caddr_t mod)
{
        size_t *mdp;
 
        mdp = (size_t *)preload_search_info(mod, MODINFO_SIZE);
        if (mdp == NULL)
                return (0);
        return (*mdp);
}
 
/* Called from locore.  Convert physical pointers to kvm. Sigh. */
void
preload_bootstrap_relocate(vm_offset_t offset)
{
    caddr_t     curp;
    uint32_t    *hdr;
    vm_offset_t *ptr;
    int         next;
    
    if (preload_metadata != NULL) {
        curp = preload_metadata;
        for (;;) {
            hdr = (uint32_t *)curp;
            if (hdr[0] == 0 && hdr[1] == 0)
                break;
 
            /* Deal with the ones that we know we have to fix */
            switch (hdr[0]) {
            case MODINFO_ADDR:
            case MODINFO_METADATA|MODINFOMD_FONT:
            case MODINFO_METADATA|MODINFOMD_SSYM:
            case MODINFO_METADATA|MODINFOMD_ESYM:
                ptr = (vm_offset_t *)(curp + (sizeof(uint32_t) * 2));
                *ptr += offset;
                break;
            }
            /* The rest is beyond us for now */
 
            /* skip to next field */
            next = sizeof(uint32_t) * 2 + hdr[1];
            next = roundup(next, sizeof(u_long));
            curp += next;
        }
    }
}
 
/*
 * Parse the modinfo type and append to the provided sbuf.
 */
static void
preload_modinfo_type(struct sbuf *sbp, int type)
{
 
        if ((type & MODINFO_METADATA) == 0) {
                switch (type) {
                case MODINFO_END:
                        sbuf_cat(sbp, "MODINFO_END");
                        break;
                case MODINFO_NAME:
                        sbuf_cat(sbp, "MODINFO_NAME");
                        break;
                case MODINFO_TYPE:
                        sbuf_cat(sbp, "MODINFO_TYPE");
                        break;
                case MODINFO_ADDR:
                        sbuf_cat(sbp, "MODINFO_ADDR");
                        break;
                case MODINFO_SIZE:
                        sbuf_cat(sbp, "MODINFO_SIZE");
                        break;
                case MODINFO_EMPTY:
                        sbuf_cat(sbp, "MODINFO_EMPTY");
                        break;
                case MODINFO_ARGS:
                        sbuf_cat(sbp, "MODINFO_ARGS");
                        break;
                default:
                        sbuf_cat(sbp, "unrecognized modinfo attribute");
                }
 
                return;
        }
 
        sbuf_cat(sbp, "MODINFO_METADATA | ");
        switch (type & ~MODINFO_METADATA) {
        case MODINFOMD_ELFHDR:
                sbuf_cat(sbp, "MODINFOMD_ELFHDR");
                break;
        case MODINFOMD_SSYM:
                sbuf_cat(sbp, "MODINFOMD_SSYM");
                break;
        case MODINFOMD_ESYM:
                sbuf_cat(sbp, "MODINFOMD_ESYM");
                break;
        case MODINFOMD_DYNAMIC:
                sbuf_cat(sbp, "MODINFOMD_DYNAMIC");
                break;
        case MODINFOMD_ENVP:
                sbuf_cat(sbp, "MODINFOMD_ENVP");
                break;
        case MODINFOMD_HOWTO:
                sbuf_cat(sbp, "MODINFOMD_HOWTO");
                break;
        case MODINFOMD_KERNEND:
                sbuf_cat(sbp, "MODINFOMD_KERNEND");
                break;
        case MODINFOMD_SHDR:
                sbuf_cat(sbp, "MODINFOMD_SHDR");
                break;
        case MODINFOMD_CTORS_ADDR:
                sbuf_cat(sbp, "MODINFOMD_CTORS_ADDR");
                break;
        case MODINFOMD_CTORS_SIZE:
                sbuf_cat(sbp, "MODINFOMD_CTORS_SIZE");
                break;
        case MODINFOMD_FW_HANDLE:
                sbuf_cat(sbp, "MODINFOMD_FW_HANDLE");
                break;
        case MODINFOMD_KEYBUF:
                sbuf_cat(sbp, "MODINFOMD_KEYBUF");
                break;
#ifdef MODINFOMD_SMAP
        case MODINFOMD_SMAP:
                sbuf_cat(sbp, "MODINFOMD_SMAP");
                break;
#endif
#ifdef MODINFOMD_SMAP_XATTR
        case MODINFOMD_SMAP_XATTR:
                sbuf_cat(sbp, "MODINFOMD_SMAP_XATTR");
                break;
#endif
#ifdef MODINFOMD_DTBP
        case MODINFOMD_DTBP:
                sbuf_cat(sbp, "MODINFOMD_DTBP");
                break;
#endif
#ifdef MODINFOMD_EFI_MAP
        case MODINFOMD_EFI_MAP:
                sbuf_cat(sbp, "MODINFOMD_EFI_MAP");
                break;
#endif
#ifdef MODINFOMD_EFI_FB
        case MODINFOMD_EFI_FB:
                sbuf_cat(sbp, "MODINFOMD_EFI_FB");
                break;
#endif
#ifdef MODINFOMD_MODULEP
        case MODINFOMD_MODULEP:
                sbuf_cat(sbp, "MODINFOMD_MODULEP");
                break;
#endif
#ifdef MODINFOMD_VBE_FB
        case MODINFOMD_VBE_FB:
                sbuf_cat(sbp, "MODINFOMD_VBE_FB");
                break;
#endif
#ifdef MODINFOMD_FONT
        case MODINFOMD_FONT:
                sbuf_cat(sbp, "MODINFOMD_FONT");
                break;
#endif
        default:
                sbuf_cat(sbp, "unrecognized metadata type");
        }
}
 
/*
 * Print the modinfo value, depending on type.
 */
static void
preload_modinfo_value(struct sbuf *sbp, uint32_t *bptr, int type, int len)
{
#ifdef __LP64__
#define sbuf_print_vmoffset(sb, o)      sbuf_printf(sb, "0x%016lx", o);
#else
#define sbuf_print_vmoffset(sb, o)      sbuf_printf(sb, "0x%08x", o);
#endif
 
        switch (type) {
        case MODINFO_NAME:
        case MODINFO_TYPE:
        case MODINFO_ARGS:
                sbuf_printf(sbp, "%s", (char *)bptr);
                break;
        case MODINFO_SIZE:
        case MODINFO_METADATA | MODINFOMD_CTORS_SIZE:
                sbuf_printf(sbp, "%lu", *(u_long *)bptr);
                break;
        case MODINFO_ADDR:
        case MODINFO_METADATA | MODINFOMD_SSYM:
        case MODINFO_METADATA | MODINFOMD_ESYM:
        case MODINFO_METADATA | MODINFOMD_DYNAMIC:
        case MODINFO_METADATA | MODINFOMD_KERNEND:
        case MODINFO_METADATA | MODINFOMD_ENVP:
        case MODINFO_METADATA | MODINFOMD_CTORS_ADDR:
#ifdef MODINFOMD_SMAP
        case MODINFO_METADATA | MODINFOMD_SMAP:
#endif
#ifdef MODINFOMD_SMAP_XATTR
        case MODINFO_METADATA | MODINFOMD_SMAP_XATTR:
#endif
#ifdef MODINFOMD_DTBP
        case MODINFO_METADATA | MODINFOMD_DTBP:
#endif
#ifdef MODINFOMD_EFI_FB
        case MODINFO_METADATA | MODINFOMD_EFI_FB:
#endif
#ifdef MODINFOMD_VBE_FB
        case MODINFO_METADATA | MODINFOMD_VBE_FB:
#endif
#ifdef MODINFOMD_FONT
        case MODINFO_METADATA | MODINFOMD_FONT:
#endif
                sbuf_print_vmoffset(sbp, *(vm_offset_t *)bptr);
                break;
        case MODINFO_METADATA | MODINFOMD_HOWTO:
                sbuf_printf(sbp, "0x%08x", *bptr);
                break;
        case MODINFO_METADATA | MODINFOMD_SHDR:
        case MODINFO_METADATA | MODINFOMD_ELFHDR:
        case MODINFO_METADATA | MODINFOMD_FW_HANDLE:
        case MODINFO_METADATA | MODINFOMD_KEYBUF:
#ifdef MODINFOMD_EFI_MAP
        case MODINFO_METADATA | MODINFOMD_EFI_MAP:
#endif
                /* Don't print data buffers. */
                sbuf_cat(sbp, "buffer contents omitted");
                break;
        default:
                break;
        }
#undef sbuf_print_vmoffset
}
 
static void
preload_dump_internal(struct sbuf *sbp)
{
        uint32_t *bptr, type, len;
 
        KASSERT(preload_metadata != NULL,
            ("%s called without setting up preload_metadata", __func__));
 
        /*
         * Iterate through the TLV-encoded sections.
         */
        bptr = (uint32_t *)preload_metadata;
        sbuf_putc(sbp, '\n');
        while (bptr[0] != MODINFO_END || bptr[1] != MODINFO_END) {
                sbuf_printf(sbp, " %p:\n", bptr);
                type = *bptr++;
                len = *bptr++;
 
                sbuf_printf(sbp, "\ttype:\t(%#04x) ", type);
                preload_modinfo_type(sbp, type);
                sbuf_putc(sbp, '\n');
                sbuf_printf(sbp, "\tlen:\t%u\n", len);
                sbuf_cat(sbp, "\tvalue:\t");
                preload_modinfo_value(sbp, bptr, type, len);
                sbuf_putc(sbp, '\n');
 
                bptr += roundup(len, sizeof(u_long)) / sizeof(uint32_t);
        }
}
 
/*
 * Print the preloaded data to the console. Called from the machine-dependent
 * initialization routines, e.g. hammer_time().
 */
void
preload_dump(void)
{
        char buf[512];
        struct sbuf sb;
 
        /*
         * This function is expected to be called before malloc is available,
         * so use a static buffer and struct sbuf.
         */
        sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
        sbuf_set_drain(&sb, sbuf_printf_drain, NULL);
        preload_dump_internal(&sb);
 
        sbuf_finish(&sb);
        sbuf_delete(&sb);
}
 
static int
sysctl_preload_dump(SYSCTL_HANDLER_ARGS)
{
        struct sbuf sb;
        int error;
 
        if (preload_metadata == NULL)
                return (EINVAL);
 
        sbuf_new_for_sysctl(&sb, NULL, 512, req);
        preload_dump_internal(&sb);
 
        error = sbuf_finish(&sb);
        sbuf_delete(&sb);
 
        return (error);
}
SYSCTL_PROC(_debug, OID_AUTO, dump_modinfo,
    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
    NULL, 0, sysctl_preload_dump, "A",
    "pretty-print the bootloader metadata");