mirror of
https://github.com/topjohnwu/Magisk.git
synced 2024-11-25 11:05:34 +00:00
02dc1172be
Since we no longer need to add new properties in the device tree, and all the patches we do removes strings, we can just directly patch the flat device tree in-place, ignoring basically all the higher level DTB structure and format to accomplish 100% compatibility.
455 lines
12 KiB
C++
455 lines
12 KiB
C++
#include <unistd.h>
|
|
#include <sys/mman.h>
|
|
#include <bitset>
|
|
#include <vector>
|
|
#include <map>
|
|
|
|
#include <utils.hpp>
|
|
|
|
#include "magiskboot.hpp"
|
|
#include "dtb.hpp"
|
|
extern "C" {
|
|
#include <libfdt.h>
|
|
}
|
|
|
|
using namespace std;
|
|
|
|
constexpr int MAX_DEPTH = 32;
|
|
static bitset<MAX_DEPTH> depth_set;
|
|
|
|
static void pretty_node(int depth) {
|
|
if (depth == 0)
|
|
return;
|
|
|
|
for (int i = 0; i < depth - 1; ++i)
|
|
printf(depth_set[i] ? "│ " : " ");
|
|
|
|
printf(depth_set[depth - 1] ? "├── " : "└── ");
|
|
}
|
|
|
|
static void pretty_prop(int depth) {
|
|
for (int i = 0; i < depth; ++i)
|
|
printf(depth_set[i] ? "│ " : " ");
|
|
|
|
printf(depth_set[depth] ? "│ " : " ");
|
|
}
|
|
|
|
static void print_node(const void *fdt, int node = 0, int depth = 0) {
|
|
// Print node itself
|
|
pretty_node(depth);
|
|
printf("#%d: %s\n", node, fdt_get_name(fdt, node, nullptr));
|
|
|
|
// Print properties
|
|
depth_set[depth] = fdt_first_subnode(fdt, node) >= 0;
|
|
int prop;
|
|
fdt_for_each_property_offset(prop, fdt, node) {
|
|
pretty_prop(depth);
|
|
int size;
|
|
const char *name;
|
|
auto value = static_cast<const char *>(fdt_getprop_by_offset(fdt, prop, &name, &size));
|
|
|
|
bool is_str = !(size > 1 && value[0] == 0);
|
|
if (is_str) {
|
|
// Scan through value to see if printable
|
|
for (int i = 0; i < size; ++i) {
|
|
char c = value[i];
|
|
if (i == size - 1) {
|
|
// Make sure null terminate
|
|
is_str = c == '\0';
|
|
} else if ((c > 0 && c < 32) || c >= 127) {
|
|
is_str = false;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (is_str) {
|
|
printf("[%s]: [%s]\n", name, value);
|
|
} else {
|
|
printf("[%s]: <bytes>(%d)\n", name, size);
|
|
}
|
|
}
|
|
|
|
// Recursive
|
|
if (depth_set[depth]) {
|
|
int child;
|
|
int prev = -1;
|
|
fdt_for_each_subnode(child, fdt, node) {
|
|
if (prev >= 0)
|
|
print_node(fdt, prev, depth + 1);
|
|
prev = child;
|
|
}
|
|
depth_set[depth] = false;
|
|
print_node(fdt, prev, depth + 1);
|
|
}
|
|
}
|
|
|
|
static int find_fstab(const void *fdt, int node = 0) {
|
|
if (fdt_get_name(fdt, node, nullptr) == "fstab"sv)
|
|
return node;
|
|
int child;
|
|
fdt_for_each_subnode(child, fdt, node) {
|
|
int fstab = find_fstab(fdt, child);
|
|
if (fstab >= 0)
|
|
return fstab;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
static void dtb_print(const char *file, bool fstab) {
|
|
size_t size;
|
|
uint8_t *dtb;
|
|
fprintf(stderr, "Loading dtbs from [%s]\n", file);
|
|
mmap_ro(file, dtb, size);
|
|
// Loop through all the dtbs
|
|
int dtb_num = 0;
|
|
for (int i = 0; i < size; ++i) {
|
|
if (memcmp(dtb + i, FDT_MAGIC_STR, 4) == 0) {
|
|
auto fdt = dtb + i;
|
|
if (fstab) {
|
|
int node = find_fstab(fdt);
|
|
if (node >= 0) {
|
|
fprintf(stderr, "Found fstab in dtb.%04d\n", dtb_num);
|
|
print_node(fdt, node);
|
|
}
|
|
} else {
|
|
fprintf(stderr, "Printing dtb.%04d\n", dtb_num);
|
|
print_node(fdt);
|
|
}
|
|
++dtb_num;
|
|
i += fdt_totalsize(fdt) - 1;
|
|
}
|
|
}
|
|
fprintf(stderr, "\n");
|
|
munmap(dtb, size);
|
|
}
|
|
|
|
static bool dtb_patch(const char *file) {
|
|
bool keepverity = check_env("KEEPVERITY");
|
|
bool patched = false;
|
|
size_t size;
|
|
uint8_t *dtb;
|
|
fprintf(stderr, "Loading dtbs from [%s]\n", file);
|
|
mmap_rw(file, dtb, size);
|
|
// Loop through all the dtbs
|
|
int dtb_num = 0;
|
|
for (int i = 0; i < size; ++i) {
|
|
if (memcmp(dtb + i, FDT_MAGIC_STR, 4) == 0) {
|
|
auto fdt = dtb + i;
|
|
fprintf(stderr, "Loading dtb.%04d\n", dtb_num);
|
|
if (int fstab = find_fstab(fdt); fstab >= 0) {
|
|
int node;
|
|
fdt_for_each_subnode(node, fdt, fstab) {
|
|
const char *name = fdt_get_name(fdt, node, nullptr);
|
|
fprintf(stderr, "Found fstab entry [%s]\n", name);
|
|
if (!keepverity) {
|
|
int len;
|
|
auto value = fdt_getprop(fdt, node, "fsmgr_flags", &len);
|
|
patched |= patch_verity(const_cast<void *>(value), len) != len;
|
|
}
|
|
}
|
|
}
|
|
++dtb_num;
|
|
i += fdt_totalsize(fdt) - 1;
|
|
}
|
|
}
|
|
fprintf(stderr, "\n");
|
|
munmap(dtb, size);
|
|
return patched;
|
|
}
|
|
|
|
int dtb_commands(int argc, char *argv[]) {
|
|
char *dtb = argv[0];
|
|
++argv;
|
|
--argc;
|
|
|
|
if (argv[0] == "print"sv) {
|
|
dtb_print(dtb, argc > 1 && argv[1] == "-f"sv);
|
|
return 0;
|
|
} else if (argv[0] == "patch"sv) {
|
|
if (!dtb_patch(dtb))
|
|
exit(1);
|
|
return 0;
|
|
} else {
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
namespace {
|
|
// Unused, but keep these precious code as they took TONs of effort to write
|
|
|
|
struct fdt_blob {
|
|
void *fdt;
|
|
uint32_t offset;
|
|
uint32_t len;
|
|
};
|
|
|
|
template <class Iter>
|
|
class fdt_map_iter {
|
|
public:
|
|
typedef decltype(std::declval<typename Iter::value_type::second_type>().fdt) value_type;
|
|
typedef value_type* pointer;
|
|
typedef value_type& reference;
|
|
|
|
explicit fdt_map_iter(Iter j) : i(j) {}
|
|
fdt_map_iter& operator++() { ++i; return *this; }
|
|
fdt_map_iter operator++(int) { auto tmp = *this; ++(*this); return tmp; }
|
|
fdt_map_iter& operator--() { --i; return *this; }
|
|
fdt_map_iter operator--(int) { auto tmp = *this; --(*this); return tmp; }
|
|
bool operator==(fdt_map_iter j) const { return i == j.i; }
|
|
bool operator!=(fdt_map_iter j) const { return !(*this == j); }
|
|
reference operator*() { return i->second.fdt; }
|
|
pointer operator->() { return &i->second.fdt; }
|
|
private:
|
|
Iter i;
|
|
};
|
|
|
|
template<class Iter>
|
|
inline fdt_map_iter<Iter> make_iter(Iter j) { return fdt_map_iter<Iter>(j); }
|
|
|
|
template <typename Iter>
|
|
static bool fdt_patch(Iter first, Iter last) {
|
|
bool keepverity = check_env("KEEPVERITY");
|
|
bool redirect = check_env("TWOSTAGEINIT");
|
|
bool modified = false;
|
|
|
|
int idx = 0;
|
|
for (auto it = first; it != last; ++it) {
|
|
++idx;
|
|
auto fdt = *it;
|
|
int fstab = find_fstab(fdt);
|
|
if (fstab < 0)
|
|
continue;
|
|
fprintf(stderr, "Found fstab in dtb.%04d\n", idx - 1);
|
|
int block;
|
|
fdt_for_each_subnode(block, fdt, fstab) {
|
|
const char *name = fdt_get_name(fdt, block, nullptr);
|
|
fprintf(stderr, "Found entry [%s] in fstab\n", name);
|
|
if (!keepverity) {
|
|
int size;
|
|
auto value = fdt_getprop(fdt, block, "fsmgr_flags", &size);
|
|
char *copy = static_cast<char *>(memcpy(malloc(size), value, size));
|
|
if (patch_verity(copy, size) != size) {
|
|
modified = true;
|
|
fdt_setprop_string(fdt, block, "fsmgr_flags", copy);
|
|
}
|
|
free(copy);
|
|
}
|
|
if (redirect && name == "system"sv) {
|
|
modified = true;
|
|
fprintf(stderr, "Changing mnt_point to /system_root\n");
|
|
fdt_setprop_string(fdt, block, "mnt_point", "/system_root");
|
|
}
|
|
}
|
|
}
|
|
return modified;
|
|
}
|
|
|
|
#define MAX_FDT_GROWTH 256
|
|
|
|
template <class Table, class Header>
|
|
static int dt_table_patch(const Header *hdr, const char *out) {
|
|
map<uint32_t, fdt_blob> dtb_map;
|
|
auto buf = reinterpret_cast<const uint8_t *>(hdr);
|
|
auto tables = reinterpret_cast<const Table *>(hdr + 1);
|
|
|
|
constexpr bool is_dt_table = std::is_same_v<Header, dt_table_header>;
|
|
|
|
using endian_conv = uint32_t (*)(uint32_t);
|
|
endian_conv be_to_le;
|
|
endian_conv le_to_be;
|
|
if constexpr (is_dt_table) {
|
|
be_to_le = fdt32_to_cpu;
|
|
le_to_be = cpu_to_fdt32;
|
|
} else {
|
|
be_to_le = le_to_be = [](uint32_t x) -> auto { return x; };
|
|
}
|
|
|
|
// Collect all dtbs
|
|
auto num_dtb = be_to_le(hdr->num_dtbs);
|
|
for (int i = 0; i < num_dtb; ++i) {
|
|
auto offset = be_to_le(tables[i].offset);
|
|
if (dtb_map.count(offset) == 0) {
|
|
auto blob = buf + offset;
|
|
uint32_t size = fdt_totalsize(blob);
|
|
auto fdt = xmalloc(size + MAX_FDT_GROWTH);
|
|
memcpy(fdt, blob, size);
|
|
fdt_open_into(fdt, fdt, size + MAX_FDT_GROWTH);
|
|
dtb_map[offset] = { fdt, offset };
|
|
}
|
|
}
|
|
if (dtb_map.empty())
|
|
return 1;
|
|
|
|
// Patch fdt
|
|
if (!fdt_patch(make_iter(dtb_map.begin()), make_iter(dtb_map.end())))
|
|
return 1;
|
|
|
|
unlink(out);
|
|
int fd = xopen(out, O_RDWR | O_CREAT | O_CLOEXEC, 0644);
|
|
|
|
uint32_t total_size = 0;
|
|
|
|
// Copy headers and tables
|
|
total_size += xwrite(fd, buf, dtb_map.begin()->first);
|
|
|
|
// mmap rw to patch table values retroactively
|
|
auto mmap_sz = lseek(fd, 0, SEEK_CUR);
|
|
auto addr = (uint8_t *) xmmap(nullptr, mmap_sz, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
|
|
|
|
// Guess alignment using gcd
|
|
uint32_t align = 1;
|
|
if constexpr (!is_dt_table) {
|
|
auto it = dtb_map.begin();
|
|
align = (it++)->first;
|
|
for (; it != dtb_map.end(); ++it)
|
|
align = binary_gcd(align, it->first);
|
|
}
|
|
|
|
// Write dtbs
|
|
for (auto &val : dtb_map) {
|
|
val.second.offset = lseek(fd, 0, SEEK_CUR);
|
|
auto fdt = val.second.fdt;
|
|
fdt_pack(fdt);
|
|
auto size = fdt_totalsize(fdt);
|
|
total_size += xwrite(fd, fdt, size);
|
|
val.second.len = do_align(size, align);
|
|
write_zero(fd, align_off(lseek(fd, 0, SEEK_CUR), align));
|
|
// total_size += align_off(lseek(fd, 0, SEEK_CUR), align); /* Not needed */
|
|
free(fdt);
|
|
}
|
|
|
|
// Patch headers
|
|
if constexpr (is_dt_table) {
|
|
auto hdr_rw = reinterpret_cast<Header *>(addr);
|
|
hdr_rw->total_size = le_to_be(total_size);
|
|
}
|
|
auto tables_rw = reinterpret_cast<Table *>(addr + sizeof(Header));
|
|
for (int i = 0; i < num_dtb; ++i) {
|
|
auto &blob = dtb_map[be_to_le(tables_rw[i].offset)];
|
|
tables_rw[i].offset = le_to_be(blob.offset);
|
|
tables_rw[i].len = le_to_be(blob.len);
|
|
}
|
|
|
|
munmap(addr, mmap_sz);
|
|
close(fd);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int blob_patch(uint8_t *dtb, size_t dtb_sz, const char *out) {
|
|
vector<uint8_t *> fdt_list;
|
|
vector<uint32_t> padding_list;
|
|
for (int i = 0; i < dtb_sz; ++i) {
|
|
if (memcmp(dtb + i, FDT_MAGIC_STR, 4) == 0) {
|
|
auto len = fdt_totalsize(dtb + i);
|
|
auto fdt = static_cast<uint8_t *>(xmalloc(len + MAX_FDT_GROWTH));
|
|
memcpy(fdt, dtb + i, len);
|
|
fdt_pack(fdt);
|
|
uint32_t padding = len - fdt_totalsize(fdt);
|
|
padding_list.push_back(padding);
|
|
fdt_open_into(fdt, fdt, len + MAX_FDT_GROWTH);
|
|
fdt_list.push_back(fdt);
|
|
i += len - 1;
|
|
}
|
|
}
|
|
|
|
if (!fdt_patch(fdt_list.begin(), fdt_list.end()))
|
|
return 1;
|
|
|
|
unlink(out);
|
|
int fd = xopen(out, O_WRONLY | O_CREAT | O_CLOEXEC, 0644);
|
|
|
|
for (int i = 0; i < fdt_list.size(); ++i) {
|
|
auto fdt = fdt_list[i];
|
|
fdt_pack(fdt);
|
|
// Only add padding back if it is anything meaningful
|
|
if (padding_list[i] > 4) {
|
|
auto len = fdt_totalsize(fdt);
|
|
fdt_set_totalsize(fdt, len + padding_list[i]);
|
|
}
|
|
xwrite(fd, fdt, fdt_totalsize(fdt));
|
|
free(fdt);
|
|
}
|
|
close(fd);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define MATCH(s) (memcmp(dtb, s, sizeof(s) - 1) == 0)
|
|
|
|
[[maybe_unused]] static int dtb_patch(const char *in, const char *out) {
|
|
if (!out)
|
|
out = in;
|
|
size_t dtb_sz ;
|
|
uint8_t *dtb;
|
|
fprintf(stderr, "Loading dtbs from [%s]\n", in);
|
|
mmap_ro(in, dtb, dtb_sz);
|
|
run_finally f([&]{ munmap(dtb, dtb_sz); });
|
|
|
|
if (MATCH(QCDT_MAGIC)) {
|
|
auto hdr = reinterpret_cast<qcdt_hdr*>(dtb);
|
|
switch (hdr->version) {
|
|
case 1:
|
|
fprintf(stderr, "QCDT v1\n");
|
|
return dt_table_patch<qctable_v1>(hdr, out);
|
|
case 2:
|
|
fprintf(stderr, "QCDT v2\n");
|
|
return dt_table_patch<qctable_v2>(hdr, out);
|
|
case 3:
|
|
fprintf(stderr, "QCDT v3\n");
|
|
return dt_table_patch<qctable_v3>(hdr, out);
|
|
default:
|
|
return 1;
|
|
}
|
|
} else if (MATCH(DTBH_MAGIC)) {
|
|
auto hdr = reinterpret_cast<dtbh_hdr *>(dtb);
|
|
switch (hdr->version) {
|
|
case 2:
|
|
fprintf(stderr, "DTBH v2\n");
|
|
return dt_table_patch<bhtable_v2>(hdr, out);
|
|
default:
|
|
return 1;
|
|
}
|
|
} else if (MATCH(PXADT_MAGIC)) {
|
|
auto hdr = reinterpret_cast<pxadt_hdr *>(dtb);
|
|
switch (hdr->version) {
|
|
case 1:
|
|
fprintf(stderr, "PXA-DT v1\n");
|
|
return dt_table_patch<pxatable_v1>(hdr, out);
|
|
default:
|
|
return 1;
|
|
}
|
|
} else if (MATCH(PXA19xx_MAGIC)) {
|
|
auto hdr = reinterpret_cast<pxa19xx_hdr *>(dtb);
|
|
switch (hdr->version) {
|
|
case 1:
|
|
fprintf(stderr, "PXA-19xx v1\n");
|
|
return dt_table_patch<pxatable_v1>(hdr, out);
|
|
default:
|
|
return 1;
|
|
}
|
|
} else if (MATCH(SPRD_MAGIC)) {
|
|
auto hdr = reinterpret_cast<sprd_hdr *>(dtb);
|
|
switch (hdr->version) {
|
|
case 1:
|
|
fprintf(stderr, "SPRD v1\n");
|
|
return dt_table_patch<sprdtable_v1>(hdr, out);
|
|
default:
|
|
return 1;
|
|
}
|
|
} else if (MATCH(DT_TABLE_MAGIC)) {
|
|
auto hdr = reinterpret_cast<dt_table_header *>(dtb);
|
|
switch (hdr->version) {
|
|
case 0:
|
|
fprintf(stderr, "DT_TABLE v0\n");
|
|
return dt_table_patch<dt_table_entry>(hdr, out);
|
|
default:
|
|
return 1;
|
|
}
|
|
} else {
|
|
return blob_patch(dtb, dtb_sz, out);
|
|
}
|
|
}
|
|
}
|