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sortix--sortix/kernel/initrd.cpp

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/*
* Copyright (c) 2011, 2012, 2013, 2014, 2015, 2016 Jonas 'Sortie' Termansen.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* initrd.cpp
* Extracts initrds into the initial memory filesystem.
*/
#include <sys/types.h>
#include <assert.h>
#include <errno.h>
#include <libgen.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <timespec.h>
#include <sortix/dirent.h>
#include <sortix/fcntl.h>
#include <sortix/initrd.h>
#include <sortix/mman.h>
#include <sortix/stat.h>
#include <sortix/tar.h>
#include <sortix/kernel/addralloc.h>
#include <sortix/kernel/descriptor.h>
#include <sortix/kernel/fsfunc.h>
#include <sortix/kernel/ioctx.h>
#include <sortix/kernel/kernel.h>
#include <sortix/kernel/memorymanagement.h>
#include <sortix/kernel/string.h>
#include <sortix/kernel/syscall.h>
#include <sortix/kernel/vnode.h>
#include "initrd.h"
#include "multiboot.h"
namespace Sortix {
// TODO: The initrd is not being properly verified.
// TODO: The initrd is not handled in an endian-neutral manner.
struct initrd_context
{
uint8_t* initrd;
size_t initrd_size;
addr_t initrd_unmap_start;
addr_t initrd_unmap_end;
struct initrd_superblock* sb;
Ref<Descriptor> links;
ioctx_t ioctx;
};
// TODO: GRUB is currently buggy and doesn't ensure that other things are placed
// at the end of a module, i.e. that the module doesn't own all the bugs
// that it spans. It's thus risky to actually recycle the last page if the
// module doesn't use all of it. Remove this compatibility when this has
// been fixed in GRUB and a few years have passed such that most GRUB
// systems have this fixed.
static void UnmapInitrdPage(struct initrd_context* ctx, addr_t vaddr)
{
if ( !Memory::LookUp(vaddr, NULL, NULL) )
return;
addr_t addr = Memory::Unmap(vaddr);
if ( !(ctx->initrd_unmap_start <= addr && addr < ctx->initrd_unmap_end) )
return;
Page::Put(addr, PAGE_USAGE_WASNT_ALLOCATED);
}
static mode_t initrd_mode_to_host_mode(uint32_t mode)
{
mode_t result = mode & 0777;
if ( INITRD_S_ISVTX & mode ) result |= S_ISVTX;
if ( INITRD_S_ISSOCK(mode) ) result |= S_IFSOCK;
if ( INITRD_S_ISLNK(mode) ) result |= S_IFLNK;
if ( INITRD_S_ISREG(mode) ) result |= S_IFREG;
if ( INITRD_S_ISBLK(mode) ) result |= S_IFBLK;
if ( INITRD_S_ISDIR(mode) ) result |= S_IFDIR;
if ( INITRD_S_ISCHR(mode) ) result |= S_IFCHR;
if ( INITRD_S_ISFIFO(mode) ) result |= S_IFIFO;
return result;
}
static struct initrd_inode* initrd_get_inode(struct initrd_context* ctx,
uint32_t inode)
{
if ( ctx->sb->inodecount <= inode )
return errno = EINVAL, (struct initrd_inode*) NULL;
uint32_t pos = ctx->sb->inodeoffset + ctx->sb->inodesize * inode;
return (struct initrd_inode*) (ctx->initrd + pos);
}
static uint8_t* initrd_inode_get_data(struct initrd_context* ctx,
struct initrd_inode* inode,
size_t* size)
{
return *size = inode->size, ctx->initrd + inode->dataoffset;
}
static uint32_t initrd_directory_open(struct initrd_context* ctx,
struct initrd_inode* inode,
const char* name)
{
if ( !INITRD_S_ISDIR(inode->mode) )
return errno = ENOTDIR, 0;
uint32_t offset = 0;
while ( offset < inode->size )
{
uint32_t pos = inode->dataoffset + offset;
struct initrd_dirent* dirent =
(struct initrd_dirent*) (ctx->initrd + pos);
if ( dirent->namelen && !strcmp(dirent->name, name) )
return dirent->inode;
offset += dirent->reclen;
}
return errno = ENOENT, 0;
}
static const char* initrd_directory_get_filename(struct initrd_context* ctx,
struct initrd_inode* inode,
size_t index)
{
if ( !INITRD_S_ISDIR(inode->mode) )
return errno = ENOTDIR, (const char*) NULL;
uint32_t offset = 0;
while ( offset < inode->size )
{
uint32_t pos = inode->dataoffset + offset;
struct initrd_dirent* dirent =
(struct initrd_dirent*) (ctx->initrd + pos);
if ( index-- == 0 )
return dirent->name;
offset += dirent->reclen;
}
return errno = EINVAL, (const char*) NULL;
}
static size_t initrd_directory_get_num_files(struct initrd_context* ctx,
struct initrd_inode* inode)
{
if ( !INITRD_S_ISDIR(inode->mode) )
return errno = ENOTDIR, 0;
uint32_t offset = 0;
size_t numentries = 0;
while ( offset < inode->size )
{
uint32_t pos = inode->dataoffset + offset;
const struct initrd_dirent* dirent =
(const struct initrd_dirent*) (ctx->initrd + pos);
numentries++;
offset += dirent->reclen;
}
return numentries;
}
static void ExtractNode(struct initrd_context* ctx,
struct initrd_inode* inode,
Ref<Descriptor> node);
static void ExtractFile(struct initrd_context* ctx,
struct initrd_inode* inode,
Ref<Descriptor> file)
{
size_t filesize;
uint8_t* data = initrd_inode_get_data(ctx, inode, &filesize);
if ( file->truncate(&ctx->ioctx, filesize) != 0 )
PanicF("initrd: truncate: %m");
size_t sofar = 0;
while ( sofar < filesize )
{
size_t left = filesize - sofar;
size_t chunk = 1024 * 1024;
size_t count = left < chunk ? left : chunk;
ssize_t numbytes = file->write(&ctx->ioctx, data + sofar, count);
if ( numbytes <= 0 )
PanicF("initrd: write: %m");
sofar += numbytes;
}
}
static void ExtractDir(struct initrd_context* ctx,
struct initrd_inode* inode,
Ref<Descriptor> dir)
{
size_t numfiles = initrd_directory_get_num_files(ctx, inode);
for ( size_t i = 0; i < numfiles; i++ )
{
const char* name = initrd_directory_get_filename(ctx, inode, i);
if ( !name )
PanicF("initrd_directory_get_filename: %m");
if ( IsDotOrDotDot(name) )
continue;
uint32_t childino = initrd_directory_open(ctx, inode, name);
if ( !childino )
PanicF("initrd_directory_open: %s: %m", name);
struct initrd_inode* child =
(struct initrd_inode*) initrd_get_inode(ctx, childino);
mode_t mode = initrd_mode_to_host_mode(child->mode);
if ( INITRD_S_ISDIR(child->mode) )
{
if ( dir->mkdir(&ctx->ioctx, name, mode) && errno != EEXIST )
PanicF("initrd: mkdir: %s: %m", name);
Ref<Descriptor> desc = dir->open(&ctx->ioctx, name,
O_SEARCH | O_DIRECTORY, 0);
if ( !desc )
PanicF("initrd: %s: %m", name);
ExtractNode(ctx, child, desc);
}
if ( INITRD_S_ISREG(child->mode) )
{
assert(child->nlink != 0);
char link_path[sizeof(childino) * 3];
snprintf(link_path, sizeof(link_path), "%ju", (uintmax_t) childino);
Ref<Descriptor> existing(ctx->links->open(&ctx->ioctx, link_path,
O_READ, 0));
if ( !existing || dir->link(&ctx->ioctx, name, existing) != 0 )
{
Ref<Descriptor> desc(dir->open(&ctx->ioctx, name,
O_WRITE | O_CREATE, mode));
if ( !desc )
PanicF("initrd: %s: %m", name);
ExtractNode(ctx, child, desc);
if ( 2 <= child->nlink )
ctx->links->link(&ctx->ioctx, link_path, desc);
}
if ( --child->nlink == 0 && INITRD_S_ISREG(child->mode) )
{
size_t filesize;
const uint8_t* data =
initrd_inode_get_data(ctx, child, &filesize);
uintptr_t from = (uintptr_t) data;
uintptr_t size = filesize;
uintptr_t from_aligned = Page::AlignUp(from);
uintptr_t from_distance = from_aligned - from;
if ( from_distance <= size )
{
uintptr_t size_aligned =
Page::AlignDown(size - from_distance);
for ( size_t i = 0; i < size_aligned; i += Page::Size() )
UnmapInitrdPage(ctx, from_aligned + i);
Memory::Flush();
}
}
}
if ( INITRD_S_ISLNK(child->mode) )
{
size_t filesize;
uint8_t* data = initrd_inode_get_data(ctx, child, &filesize);
char* oldname = new char[filesize + 1];
if ( !oldname )
PanicF("initrd: malloc: %m");
memcpy(oldname, data, filesize);
oldname[filesize] = '\0';
int ret = dir->symlink(&ctx->ioctx, oldname, name);
delete[] oldname;
if ( ret < 0 )
PanicF("initrd: symlink: %s", name);
Ref<Descriptor> desc = dir->open(&ctx->ioctx, name,
O_READ | O_SYMLINK_NOFOLLOW, 0);
if ( desc )
ExtractNode(ctx, child, desc);
}
}
}
static void ExtractNode(struct initrd_context* ctx,
struct initrd_inode* inode,
Ref<Descriptor> node)
{
if ( node->chmod(&ctx->ioctx, initrd_mode_to_host_mode(inode->mode)) < 0 )
PanicF("initrd: chmod: %m");
if ( node->chown(&ctx->ioctx, inode->uid, inode->gid) < 0 )
PanicF("initrd: chown: %m");
if ( INITRD_S_ISDIR(inode->mode) )
ExtractDir(ctx, inode, node);
if ( INITRD_S_ISREG(inode->mode) )
ExtractFile(ctx, inode, node);
struct timespec times[2];
times[0] = timespec_make((time_t) inode->mtime, 0);
times[1] = timespec_make((time_t) inode->mtime, 0);
if ( node->utimens(&ctx->ioctx, times) < 0 )
PanicF("initrd: utimens: %m");
}
static void ExtractInitrd(Ref<Descriptor> desc, struct initrd_context* ctx)
{
ctx->sb = (struct initrd_superblock*) ctx->initrd;
if ( ctx->initrd_size < ctx->sb->fssize )
Panic("Initrd header does not match its size");
if ( desc->mkdir(&ctx->ioctx, ".initrd-links", 0777) != 0 )
PanicF("initrd: .initrd-links: %m");
if ( !(ctx->links = desc->open(&ctx->ioctx, ".initrd-links",
O_READ | O_DIRECTORY, 0)) )
PanicF("initrd: .initrd-links: %m");
ExtractNode(ctx, initrd_get_inode(ctx, ctx->sb->root), desc);
union
{
struct dirent dirent;
uint8_t dirent_data[sizeof(struct dirent) + sizeof(uintmax_t) * 3];
};
while ( 0 < ctx->links->readdirents(&ctx->ioctx, &dirent, sizeof(dirent_data)) &&
((const char*) dirent.d_name)[0] )
{
if ( ((const char*) dirent.d_name)[0] == '.' )
continue;
ctx->links->unlinkat(&ctx->ioctx, dirent.d_name, AT_REMOVEFILE);
ctx->links->lseek(&ctx->ioctx, 0, SEEK_SET);
}
ctx->links.Reset();
desc->unlinkat(&ctx->ioctx, ".initrd-links", AT_REMOVEDIR);
}
struct TAR
{
unsigned char* tar_file;
size_t tar_file_size;
size_t next_offset;
size_t offset;
size_t data_offset;
char* name;
char* linkname;
unsigned char* data;
size_t size;
mode_t mode;
char typeflag;
};
static void OpenTar(TAR* TAR, unsigned char* tar_file, size_t tar_file_size)
{
memset(TAR, 0, sizeof(*TAR));
TAR->tar_file = tar_file;
TAR->tar_file_size = tar_file_size;
}
static void CloseTar(TAR* TAR)
{
free(TAR->name);
free(TAR->linkname);
memset(TAR, 0, sizeof(*TAR));
}
static bool ReadTar(TAR* TAR)
{
free(TAR->name);
free(TAR->linkname);
TAR->name = NULL;
TAR->linkname = NULL;
while ( true )
{
if ( TAR->tar_file_size - TAR->next_offset < sizeof(struct TAR) )
return false;
TAR->offset = TAR->next_offset;
struct tar* tar = (struct tar*) (TAR->tar_file + TAR->offset);
if ( tar->size[sizeof(tar->size) - 1] != '\0' )
return false;
size_t size = strtoul(tar->size, NULL, 8);
size_t dist = sizeof(struct tar) + -(-size & ~((size_t) 512 - 1));
if ( TAR->tar_file_size - TAR->offset < dist )
return false;
TAR->next_offset = TAR->offset + dist;
TAR->data_offset = TAR->offset + 512;
TAR->data = TAR->tar_file + TAR->data_offset;
TAR->size = size;
if ( tar->mode[sizeof(tar->mode) - 1] != '\0' )
return false;
TAR->mode = strtoul(tar->mode, NULL, 8) & 07777;
TAR->typeflag = tar->typeflag;
// TODO: Things like modified time and other meta data!
if ( tar->typeflag == 'L' )
{
free(TAR->name);
if ( !(TAR->name = (char*) malloc(size + 1)) )
Panic("initrd tar malloc failure");
memcpy(TAR->name, TAR->data, size);
TAR->name[size] = '\0';
continue;
}
else if ( tar->typeflag == 'g' )
{
// TODO: Implement pax extensions.
continue;
}
else if ( tar->typeflag == 'x' )
{
// TODO: Implement pax extensions.
continue;
}
if ( !tar->name[0] )
continue;
if ( !TAR->name )
{
if ( tar->prefix[0] )
{
size_t prefix_len = strnlen(tar->prefix, sizeof(tar->prefix));
size_t name_len = strnlen(tar->name, sizeof(tar->name));
size_t name_size = prefix_len + 1 + name_len + 1;
if ( !(TAR->name = (char*) malloc(name_size)) )
Panic("initrd tar malloc failure");
memcpy(TAR->name, tar->prefix, prefix_len);
TAR->name[prefix_len] = '/';
memcpy(TAR->name + prefix_len + 1, tar->name, name_len);
TAR->name[prefix_len + 1 + name_len] = '\0';
}
else
{
TAR->name = (char*) strndup(tar->name, sizeof(tar->name));
if ( !TAR->name )
Panic("initrd tar malloc failure");
}
}
if ( !TAR->linkname )
{
TAR->linkname = (char*) strndup(tar->linkname, sizeof(tar->linkname));
if ( !TAR->linkname )
Panic("initrd tar malloc failure");
}
return true;
}
}
static bool SearchTar(struct initrd_context* ctx, TAR* TAR, const char* path)
{
OpenTar(TAR, ctx->initrd, ctx->initrd_size);
while ( ReadTar(TAR) )
{
if ( !strcmp(TAR->name, path) )
return true;
}
CloseTar(TAR);
return false;
}
static void ExtractTarObject(Ref<Descriptor> desc,
struct initrd_context* ctx,
TAR* TAR)
{
if ( TAR->typeflag == '0' )
{
int oflags = O_WRITE | O_CREATE | O_TRUNC;
Ref<Descriptor> file(desc->open(&ctx->ioctx, TAR->name, oflags, TAR->mode));
if ( !file )
PanicF("%s: %m", TAR->name);
if ( file->truncate(&ctx->ioctx, TAR->size) != 0 )
PanicF("truncate: %s: %m", TAR->name);
size_t sofar = 0;
while ( sofar < TAR->size )
{
size_t left = TAR->size - sofar;
size_t chunk = 1024 * 1024;
size_t count = left < chunk ? left : chunk;
ssize_t numbytes = file->write(&ctx->ioctx, TAR->data + sofar, count);
if ( numbytes <= 0 )
PanicF("write: %s: %m", TAR->name);
sofar += numbytes;
}
}
else if ( TAR->typeflag == '1' )
{
Ref<Descriptor> dest(desc->open(&ctx->ioctx, TAR->linkname, O_READ, 0));
if ( !dest )
PanicF("%s: %m", TAR->linkname);
if ( desc->link(&ctx->ioctx, TAR->name, dest) != 0 )
PanicF("link: %s -> %s: %m", TAR->linkname, TAR->name);
}
else if ( TAR->typeflag == '2' )
{
if ( desc->symlink(&ctx->ioctx, TAR->linkname, TAR->name) != 0 )
PanicF("symlink: %s: %m", TAR->name);
}
else if ( TAR->typeflag == '5' )
{
if ( desc->mkdir(&ctx->ioctx, TAR->name, TAR->mode) && errno != EEXIST )
PanicF("mkdir: %s: %m", TAR->name);
}
else
{
Log::PrintF("kernel: initrd: %s: Unsupported tar filetype '%c'\n",
TAR->name, TAR->typeflag);
}
}
static void ExtractTar(Ref<Descriptor> desc, struct initrd_context* ctx)
{
TAR TAR;
OpenTar(&TAR, ctx->initrd, ctx->initrd_size);
while ( ReadTar(&TAR) )
ExtractTarObject(desc, ctx, &TAR);
CloseTar(&TAR);
}
static bool TarIsTix(struct initrd_context* ctx)
{
TAR TAR;
bool result = SearchTar(ctx, &TAR, "tix/tixinfo");
CloseTar(&TAR);
return result;
}
static char* tixinfo_lookup(const char* info,
size_t info_size,
const char* what)
{
size_t what_length = strlen(what);
while ( info_size )
{
size_t line_length = 0;
while ( line_length < info_size && info[line_length] != '\n' )
line_length++;
if ( what_length <= line_length &&
!strncmp(info, what, what_length) &&
info[what_length] == '=' )
{
char* result = strndup(info + what_length + 1,
line_length - (what_length + 1));
if ( !result )
Panic("initrd tar malloc failure");
return result;
}
info += line_length;
info_size -= line_length;
if ( info_size && info[0] == '\n' )
{
info++;
info_size--;
}
}
return NULL;
}
static void DescriptorWriteLine(Ref<Descriptor> desc,
ioctx_t* ioctx,
const char* str)
{
size_t len = strlen(str);
while ( str[0] )
{
ssize_t done = desc->write(ioctx, (unsigned char*) str, len);
if ( done <= 0 )
PanicF("initrd tix metadata write: %m");
str += done;
len -= done;
}
if ( desc->write(ioctx, (unsigned char*) "\n", 1) != 1 )
PanicF("initrd tix metadata write: %m");
}
static int manifest_sort(const void* a_ptr, const void* b_ptr)
{
const char* a = *(const char* const*) a_ptr;
const char* b = *(const char* const*) b_ptr;
return strcmp(a, b);
}
static void ExtractTix(Ref<Descriptor> desc, struct initrd_context* ctx)
{
TAR TAR;
if ( !SearchTar(ctx, &TAR, "tix/tixinfo") )
Panic("initrd was not tix");
char* pkg_name =
tixinfo_lookup((const char*) TAR.data, TAR.size, "pkg.name");
if ( !pkg_name )
Panic("initrd tixinfo lacked pkg.name");
if ( desc->mkdir(&ctx->ioctx, "/tix", 0755) < 0 && errno != EEXIST )
PanicF("/tix: %m");
if ( desc->mkdir(&ctx->ioctx, "/tix/tixinfo", 0755) < 0 && errno != EEXIST )
PanicF("/tix/tixinfo: %m");
if ( desc->mkdir(&ctx->ioctx, "/tix/manifest", 0755) < 0 && errno != EEXIST )
PanicF("/tix/manifest: %m");
char* tixinfo_path;
if ( asprintf(&tixinfo_path, "/tix/tixinfo/%s", pkg_name) < 0 )
Panic("initrd tar malloc failure");
char* TAR_oldname = TAR.name;
TAR.name = tixinfo_path;
ExtractTarObject(desc, ctx, &TAR);
TAR.name = TAR_oldname;
free(tixinfo_path);
CloseTar(&TAR);
Ref<Descriptor> installed_list =
desc->open(&ctx->ioctx, "/tix/installed.list",
O_CREATE | O_WRITE | O_APPEND, 0644);
if ( !installed_list )
PanicF("/tix/installed.list: %m");
DescriptorWriteLine(installed_list, &ctx->ioctx, pkg_name);
installed_list.Reset();
size_t manifest_list_size = 0;
OpenTar(&TAR, ctx->initrd, ctx->initrd_size);
while ( ReadTar(&TAR) )
{
if ( !strncmp(TAR.name, "data", 4) && TAR.name[4] == '/' )
manifest_list_size++;
}
CloseTar(&TAR);
char** manifest_list = new char*[manifest_list_size];
if ( !manifest_list )
Panic("initrd tar malloc failure");
OpenTar(&TAR, ctx->initrd, ctx->initrd_size);
size_t manifest_list_count = 0;
while ( ReadTar(&TAR) )
{
if ( strncmp(TAR.name, "data", 4) != 0 || TAR.name[4] != '/' )
continue;
if ( !(manifest_list[manifest_list_count++] = strdup(TAR.name + 4)) )
Panic("initrd tar malloc failure");
}
CloseTar(&TAR);
qsort(manifest_list, manifest_list_count, sizeof(char*), manifest_sort);
char* manifest_path;
if ( asprintf(&manifest_path, "/tix/manifest/%s", pkg_name) < 0 )
Panic("initrd tar malloc failure");
Ref<Descriptor> manifest =
desc->open(&ctx->ioctx, manifest_path, O_WRITE | O_CREATE | O_TRUNC, 0644);
if ( !manifest )
PanicF("%s: %m", manifest_path);
free(manifest_path);
for ( size_t i = 0; i < manifest_list_count; i++ )
DescriptorWriteLine(manifest, &ctx->ioctx, manifest_list[i]);
manifest.Reset();
for ( size_t i = 0; i < manifest_list_count; i++ )
free(manifest_list[i]);
delete[] manifest_list;
OpenTar(&TAR, ctx->initrd, ctx->initrd_size);
const char* subdir = "data/";
size_t subdir_length = strlen(subdir);
while ( ReadTar(&TAR) )
{
bool name_data = !strncmp(TAR.name, subdir, subdir_length) &&
TAR.name[subdir_length];
bool linkname_data = !strncmp(TAR.linkname, subdir, subdir_length) &&
TAR.linkname[subdir_length];
if ( name_data )
{
TAR.name += subdir_length;
if ( linkname_data )
TAR.linkname += subdir_length;
ExtractTarObject(desc, ctx, &TAR);
TAR.name -= subdir_length;
if ( linkname_data )
TAR.linkname -= subdir_length;
}
}
CloseTar(&TAR);
free(pkg_name);
}
static int ExtractTo_mkdir(Ref<Descriptor> desc, ioctx_t* ctx,
const char* path, mode_t mode)
{
int saved_errno = errno;
if ( !desc->mkdir(ctx, path, mode) )
return 0;
if ( errno == ENOENT )
{
char* prev = strdup(path);
if ( !prev )
return -1;
int status = ExtractTo_mkdir(desc, ctx, dirname(prev), mode | 0500);
free(prev);
if ( status < 0 )
return -1;
errno = saved_errno;
if ( !desc->mkdir(ctx, path, mode) )
return 0;
}
if ( errno == EEXIST )
return errno = saved_errno, 0;
return -1;
}
static void ExtractTo(Ref<Descriptor> desc,
struct initrd_context* ctx,
const char* path)
{
int oflags = O_WRITE | O_CREATE | O_TRUNC;
Ref<Descriptor> file(desc->open(&ctx->ioctx, path, oflags, 0644));
if ( !file && errno == ENOENT )
{
char* prev = strdup(path);
if ( !prev )
PanicF("%s: strdup: %m", path);
if ( ExtractTo_mkdir(desc, &ctx->ioctx, dirname(prev), 755) < 0 )
PanicF("%s: mkdir -p: %s: %m", path, prev);
free(prev);
file = desc->open(&ctx->ioctx, path, oflags, 0644);
}
if ( !file )
PanicF("%s: %m", path);
if ( file->truncate(&ctx->ioctx, ctx->initrd_size) != 0 )
PanicF("truncate: %s: %m", path);
size_t sofar = 0;
while ( sofar < ctx->initrd_size )
{
size_t left = ctx->initrd_size - sofar;
size_t chunk = 1024 * 1024;
size_t count = left < chunk ? left : chunk;
ssize_t numbytes = file->write(&ctx->ioctx, ctx->initrd + sofar, count);
if ( numbytes <= 0 )
PanicF("write: %s: %m", path);
sofar += numbytes;
}
}
static void ExtractModule(struct multiboot_mod_list* module,
Ref<Descriptor> desc,
struct initrd_context* ctx)
{
size_t mod_size = module->mod_end - module->mod_start;
const char* cmdline = (const char*) (uintptr_t) module->cmdline;
// Ignore the random seed.
if ( !strcmp(cmdline, "--random-seed") )
return;
// Allocate the needed kernel virtual address space.
addralloc_t initrd_addr_alloc;
if ( !AllocateKernelAddress(&initrd_addr_alloc, mod_size) )
PanicF("Failed to allocate kernel address space for the initrd");
// Map the physical frames onto our address space.
addr_t physfrom = module->mod_start;
addr_t mapat = initrd_addr_alloc.from;
for ( size_t i = 0; i < mod_size; i += Page::Size() )
{
if ( !Memory::Map(physfrom + i, mapat + i, PROT_KREAD | PROT_KWRITE) )
PanicF("Unable to map the initrd into virtual memory");
}
Memory::Flush();
ctx->initrd = (uint8_t*) initrd_addr_alloc.from;
ctx->initrd_size = mod_size;
ctx->initrd_unmap_start = module->mod_start;
ctx->initrd_unmap_end = Page::AlignDown(module->mod_end);
const unsigned char xz_magic[] = { 0xFD, '7', 'z', 'X', 'Z', 0x00 };
const unsigned char bzip2_magic[] = { 'B', 'Z' };
const unsigned char gz_magic[] = { 0x1F, 0x8B };
if ( !strncmp(cmdline, "--to ", strlen("--to ")) )
ExtractTo(desc, ctx, cmdline + strlen("--to "));
else if ( sizeof(struct initrd_superblock) <= ctx->initrd_size &&
!memcmp(ctx->initrd, "sortix-initrd-2", strlen("sortix-initrd-2")) )
ExtractInitrd(desc, ctx);
else if ( sizeof(struct tar) <= ctx->initrd_size &&
!memcmp(ctx->initrd + offsetof(struct tar, magic), "ustar", 5) )
{
if ( !strcmp(cmdline, "--tar") )
ExtractTar(desc, ctx);
else if ( !strcmp(cmdline, "--tix") )
ExtractTix(desc, ctx);
else if ( TarIsTix(ctx) )
ExtractTix(desc, ctx);
else
ExtractTar(desc, ctx);
}
else if ( sizeof(xz_magic) <= ctx->initrd_size &&
!memcmp(ctx->initrd, xz_magic, sizeof(xz_magic)) )
Panic("Bootloader failed to decompress an xz initrd, "
"or try the --to <path> option");
else if ( sizeof(gz_magic) <= ctx->initrd_size &&
!memcmp(ctx->initrd, gz_magic, sizeof(gz_magic)) )
Panic("Bootloader failed to decompress a gzip initrd, "
"or try the --to <path> option");
else if ( sizeof(bzip2_magic) <= ctx->initrd_size &&
!memcmp(ctx->initrd, bzip2_magic, sizeof(bzip2_magic)) )
Panic("Bootloader failed to decompress a bzip2 initrd, "
"or try the --to <path> option");
else
Panic("Unsupported initrd format, or try the --to <path> option");
// Unmap the pages and return the physical frames for reallocation.
for ( size_t i = 0; i < mod_size; i += Page::Size() )
UnmapInitrdPage(ctx, mapat + i);
Memory::Flush();
// Free the used virtual address space.
FreeKernelAddress(&initrd_addr_alloc);
}
void ExtractModules(struct multiboot_info* bootinfo, Ref<Descriptor> root)
{
struct multiboot_mod_list* modules =
(struct multiboot_mod_list*) (uintptr_t) bootinfo->mods_addr;
struct initrd_context ctx;
memset(&ctx, 0, sizeof(ctx));
SetupKernelIOCtx(&ctx.ioctx);
for ( uint32_t i = 0; i < bootinfo->mods_count; i++ )
ExtractModule(&modules[i], root, &ctx);
}
} // namespace Sortix
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