#include <stdio.h>
#include <stdlib.h>
+/* TODO(bernhard): use {u,}int* types */
+
+#define __USE_GNU
// Note by hs: my signal.h includes sys/uconctext which conflicts with
// asm/ucontext - this hack kinda solves the problem for me ;-)
// so feel free to blame me for that s**t
#define __USE_XOPEN2K8
#endif
-#include <asm/ucontext.h>
+#include <sys/ucontext.h>
-unsigned int getMethodEntry(unsigned int, void *, void *);
+unsigned int getMethodEntry(unsigned int, unsigned int);
+unsigned int getStaticFieldAddr(unsigned int, void*);
-void *method_map = NULL;
-void *caller_map = NULL;
+#ifdef DEBUG
+#define dprintf(args...) do { printf (args); } while (0);
+#else
+#define dprintf(args...)
+#endif
-void set_mmap(void *mmap)
-{
- printf("set_mmap: 0x%08x\n", (unsigned int) mmap);
- method_map = mmap;
-}
+#define NEW_MAP(prefix) \
+ void* prefix ## _map = NULL; \
+ void set_ ## prefix ## map(void *map) \
+ { \
+ dprintf("set_%s: 0x%08x\n", #prefix , (unsigned int) map); \
+ prefix ## _map = map; \
+ } \
+ void *get_ ## prefix ## map() \
+ { \
+ dprintf("get_%s: 0x%08x\n", #prefix , (unsigned int) prefix ## _map); \
+ return prefix ## _map; \
+ }
-void *get_mmap()
-{
- printf("get_mmap: 0x%08x\n", (unsigned int) method_map);
- return method_map;
-}
+NEW_MAP(method)
+NEW_MAP(trap)
+NEW_MAP(class)
+NEW_MAP(virtual)
+NEW_MAP(strings)
-void set_cmap(void *cmap)
-{
- printf("set_cmap: 0x%08x\n", (unsigned int) cmap);
- caller_map = cmap;
-}
-void *get_cmap()
+void mainresult(unsigned int a)
{
- printf("get_cmap: 0x%08x\n", (unsigned int) caller_map);
- return caller_map;
+ dprintf("mainresult: 0x%08x\n", a);
}
-
-void mainresult(unsigned int a)
+void callertrap(int nSignal, siginfo_t *info, void *ctx)
{
- printf("mainresult: 0x%08x\n", a);
+ mcontext_t *mctx = &((ucontext_t *) ctx)->uc_mcontext;
+ unsigned int from = (unsigned int) mctx->gregs[REG_EIP] - 2;
+ unsigned int *to_patch = (unsigned int *) (from + 1);
+ dprintf("callertrap(mctx) by 0x%08x\n", from);
+ if (*to_patch != 0x90ffff90) {
+ dprintf("callertrap: something is wrong here. abort\n");
+ exit(0);
+ }
+ unsigned int patchme = getMethodEntry(from, 0);
+
+ unsigned char *insn = (unsigned char *) from;
+ *insn = 0xe8; // call opcode
+ dprintf(" to_patch: 0x%08x\n", (unsigned int) to_patch);
+ dprintf("*to_patch: 0x%08x\n", *to_patch);
+ *to_patch = patchme - (from + 5);
+ dprintf("*to_patch: 0x%08x\n", *to_patch);
+ mctx->gregs[REG_EIP] = (unsigned long) insn;
}
-void callertrap(int nSignal, siginfo_t *info, void *ctx)
+void staticfieldtrap(int nSignal, siginfo_t *info, void *ctx)
{
- struct ucontext *uctx = (struct ucontext *) ctx;
- unsigned int from = (unsigned int) uctx->uc_mcontext.eip;
- unsigned int patchme = getMethodEntry(from, method_map, caller_map);
-
- printf("callertrap(mctx) by 0x%08x\n", from);
- // printf("callertrap(addr) by 0x%08x\n", info->si_addr);
- // printf("callertrap(*esp) by 0x%08x\n", * (unsigned int *) uctx->uc_mcontext.esp);
-
- unsigned int *to_patch = (unsigned int *) (uctx->uc_mcontext.eip + 2);
- unsigned char *insn = (unsigned char *) (uctx->uc_mcontext.eip);
- *insn = 0x90; // nop
- insn++;
- *insn = 0xe8; // call
- printf(" to_patch: 0x%08x\n", (unsigned int) to_patch);
- printf("*to_patch: 0x%08x\n", *to_patch);
+ /* TODO(bernhard): more generic and cleaner please... */
+ mcontext_t *mctx = &((ucontext_t *) ctx)->uc_mcontext;
+ unsigned int from = (unsigned int) mctx->gregs[REG_EIP];
+ if (from < 0x10000) { // invokevirtual
+ if (from > 0) {
+ dprintf("from: 0x%08x but should be 0 :-(\n", from);
+ }
+ unsigned int method_table_ptr = (unsigned int) mctx->gregs[REG_EAX];
+ unsigned int *esp = (unsigned int *) mctx->gregs[REG_ESP];
+ /* get actual eip from stack storage */
+ unsigned int from = (*esp) - 3;
+ unsigned char offset = *((unsigned char *) (*esp) - 1);
+ /* method entry to patch */
+ unsigned int *to_patch = (unsigned int*) (method_table_ptr + offset);
+ dprintf("invokevirtual by 0x%08x with offset 0x%08x\n", from, offset);
+ dprintf(" to_patch: 0x%08x\n", (unsigned int) to_patch);
+ dprintf("*to_patch: 0x%08x\n", *to_patch);
+ *to_patch = getMethodEntry(from, method_table_ptr);
+ mctx->gregs[REG_EIP] = *to_patch;
+ dprintf("*to_patch: 0x%08x\n", *to_patch);
+ } else {
+ unsigned int *to_patch = (unsigned int *) (from + 2);
+ dprintf("staticfieldtrap by 0x%08x\n", from);
if (*to_patch != 0x00000000) {
- printf("something is wrong here. abort\n");
+ dprintf("staticfieldtrap: something is wrong here. abort\n");
exit(0);
}
- *to_patch = (unsigned int) patchme - ((unsigned int) insn + 5);
- printf("*to_patch: 0x%08x\n", *to_patch);
- uctx->uc_mcontext.eip = (unsigned long) insn;
- // while (1) ;
+ unsigned int patchme = getStaticFieldAddr(from, trap_map);
+
+ dprintf(" to_patch: 0x%08x\n", (unsigned int) to_patch);
+ dprintf("*to_patch: 0x%08x\n", *to_patch);
+ *to_patch = patchme;
+ dprintf("*to_patch: 0x%08x\n", *to_patch);
+ }
}
void register_signal(void)
{
+ struct sigaction illaction;
+ illaction.sa_sigaction = callertrap;
+ sigemptyset(&illaction.sa_mask);
+ illaction.sa_flags = SA_SIGINFO | SA_RESTART | SA_NODEFER;
+ sigaction(SIGILL, &illaction, NULL);
+
struct sigaction segvaction;
- segvaction.sa_sigaction = callertrap;
+ segvaction.sa_sigaction = staticfieldtrap;
sigemptyset(&segvaction.sa_mask);
- segvaction.sa_flags = SA_SIGINFO | SA_RESTART;
+ segvaction.sa_flags = SA_SIGINFO | SA_RESTART | SA_NODEFER;
sigaction(SIGSEGV, &segvaction, NULL);
}
{
return (unsigned int) mainresult;
}
+
+unsigned int getMallocAddr(void)
+{
+ return (unsigned int) malloc;
+}