Initial original import from: fuse-2.4.2-2.fc4
[captive.git] / src / libcaptive / ps / signal.c
index 9ced3b0..68a08b3 100644 (file)
 #include "captive/mm.h"        /* for captive_mmap_map_get() */
 #include <sys/mman.h>
 #include "reactos/internal/mm.h"  /* for PAGE_SIZE */
+#include "captive/ldr.h"       /* for captive_ModuleList_patchpoint_find() */
+#include "captive/ldr_exports.h"       /* for struct captive_ModuleList_patchpoint */
 
 
-static greg_t val_exceptionstack_top=0;
-
-
+int _abnormal_termination_orig(void);
+extern greg_t fs_KPCR_ExceptionList;
 
 /**
- * _abnormal_termination:
+ * _abnormal_termination_wrap:
  *
- * This call can be also accessed as AbnormalTermination() or abnormal_termination().
+ * This call can be also accessed as AbnormalTermination() or _abnormal_termination().
+ * It is a captive wrapper around _abnormal_termination() function.
+ *
+ * Returns whether some exception occured in the current #try block we are currently
+ * #finish -ing. Any functions called from current #finish block will be considered
+ * for returning zero back again. It is forbidden to call this function outside
+ * of #finish block, result of such call is undefined.
  *
- * Returns whether some exception occured (FIXME: in what scope?).
  * Exception handlers are registered from W32 binary in stack frames stored in "fs:[0x00000000]"
- * value which gets mapped by libcaptive/ps/signal.c to #val_exceptionstack_top
+ * value which gets mapped by libcaptive/ps/signal.c to #fs_KPCR_ExceptionList
  * variable.
  *
- * libcaptive currently does not raise any exceptions therefore this call always returns value %0.
- * See RtlpDispatchException().
+ * If no exception handler was registered yet this function returns zero.
+ *
+ * See also RtlpDispatchException().
  *
- * Returns: non-zero if some exception is now registered and pending.
+ * Returns: non-zero if some exception is now being handled as pending.
  */
-int _abnormal_termination(void)
+int _abnormal_termination_wrap(void)
 {
-       return 0;
+       /* No handler registered yet? ntoskrnl _abnormal_termination() does not handle it
+        * and I do not want to bother with registering toplevel handler.
+        */
+       if (fs_KPCR_ExceptionList==(greg_t)-1)
+               return 0;
+
+       return _abnormal_termination_orig();
 }
 
 
+#if 0
+
 /**
  * RtlpDispatchException:
  * @ExceptionRecord: Ignored by libcaptive.
@@ -73,12 +88,33 @@ ULONG RtlpDispatchException(IN PEXCEPTION_RECORD ExceptionRecord,IN PCONTEXT Con
        g_return_val_if_reached(0);
 }
 
+#endif
+
+
+/* =='KeGetCurrentKPCR()->ExceptionList';
+ * libcaptive has reduced KPCR (named 'captive_KPCR') which
+ * does not contain this field
+ */
+greg_t fs_KPCR_ExceptionList=(greg_t)-1;
+
+/* FIXME */
+static greg_t fs_KPCR_Unknown638=0;
+
 
 static gboolean instr_mov_greg_to_fsmem(int greg,const void *fsmem,struct ucontext *ucontext)
 {
-       if (fsmem==0x00000000) {        /* exception stack top pointer */
+       if (fsmem==(const void *)0x00000000) {  /* exception stack top pointer */
                /* moving from %esp is required to pass! */
-               val_exceptionstack_top=ucontext->uc_mcontext.gregs[greg];
+               fs_KPCR_ExceptionList=ucontext->uc_mcontext.gregs[greg];
+               return TRUE;
+               }
+       g_return_val_if_reached(FALSE);
+}
+
+static gboolean instr_mov_immed_to_fsmem(greg_t immed,const void *fsmem,struct ucontext *ucontext)
+{
+       if (fsmem==(const void *)0x00000000) {  /* exception stack top pointer */
+               fs_KPCR_ExceptionList=immed;
                return TRUE;
                }
        g_return_val_if_reached(FALSE);
@@ -86,9 +122,48 @@ static gboolean instr_mov_greg_to_fsmem(int greg,const void *fsmem,struct uconte
 
 static gboolean instr_mov_fsmem_to_greg(const void *fsmem,int greg,struct ucontext *ucontext)
 {
-       if (fsmem==0x00000000) {        /* exception stack top pointer */
+       if (fsmem==(const void *)0x00000000) {  /* exception stack top pointer */
                /* moving to %esp is required to pass! */
-               ucontext->uc_mcontext.gregs[greg]=val_exceptionstack_top;
+               ucontext->uc_mcontext.gregs[greg]=fs_KPCR_ExceptionList;
+               return TRUE;
+               }
+       if (fsmem==(const void *)0x00000051) {  /* =='KeGetCurrentKPCR()->Number' */
+               g_return_val_if_fail(greg!=REG_ESP,FALSE);
+               ucontext->uc_mcontext.gregs[greg]=(greg_t)0;    /* ==libcaptive version of KeGetCurrentProcessorNumber() */
+               return TRUE;
+               }
+       if (fsmem==(const void *)0x00000124) {  /* =='KeGetCurrentKPCR()->CurrentThread' */
+               g_return_val_if_fail(greg!=REG_ESP,FALSE);
+               ucontext->uc_mcontext.gregs[greg]=(greg_t)captive_KeGetCurrentKPCR()->CurrentThread;
+               return TRUE;
+               }
+       g_return_val_if_reached(FALSE);
+}
+
+static gboolean instr_push_fsmem(const void *fsmem,struct ucontext *ucontext)
+{
+       if (fsmem==(const void *)0x00000000) {  /* exception stack top pointer */
+               ucontext->uc_mcontext.gregs[REG_ESP]-=4;
+               *(greg_t *)ucontext->uc_mcontext.gregs[REG_ESP]=fs_KPCR_ExceptionList;
+               return TRUE;
+               }
+       g_return_val_if_reached(FALSE);
+}
+
+static gboolean instr_pop_fsmem(const void *fsmem,struct ucontext *ucontext)
+{
+       if (fsmem==(const void *)0x00000000) {  /* exception stack top pointer */
+               fs_KPCR_ExceptionList=*(greg_t *)ucontext->uc_mcontext.gregs[REG_ESP];
+               ucontext->uc_mcontext.gregs[REG_ESP]+=4;
+               return TRUE;
+               }
+       g_return_val_if_reached(FALSE);
+}
+
+static gboolean instr_incl_fsmem(const void *fsmem,struct ucontext *ucontext)
+{
+       if (fsmem==(const void *)0x00000638) {  /* Unknown638 */
+               fs_KPCR_Unknown638++;
                return TRUE;
                }
        g_return_val_if_reached(FALSE);
@@ -111,8 +186,9 @@ static int op_regcode_to_greg(guint8 regcode)
 
 static void sigaction_SIGSEGV(int signo,siginfo_t *siginfo,struct ucontext *ucontext)
 {
-const guint8 *reg_eip;
+guint8 *reg_eip;
 const void *reg_eip_aligned;
+static const void *reg_eip_aligned_last_valid=NULL;    /* performance cache */
 
        g_return_if_fail(signo==SIGSEGV);
        g_return_if_fail(siginfo->si_signo==SIGSEGV);
@@ -125,12 +201,35 @@ const void *reg_eip_aligned;
         */
        reg_eip_aligned=(const void *)(((char *)reg_eip)-(GPOINTER_TO_UINT(reg_eip)&(PAGE_SIZE-1)));
        g_assert(reg_eip_aligned!=NULL);
-       g_return_if_fail(!(captive_mmap_map_get(reg_eip_aligned)&PROT_EXEC));
+
+       /* We do not expect any pages can get un-PROT_EXEC-ed
+        * and therefore we never invalidate our cache 'reg_eip_aligned_last_valid'.
+        */
+       if (reg_eip_aligned_last_valid!=reg_eip_aligned) {
+               g_return_if_fail(!(captive_mmap_map_get(reg_eip_aligned)&PROT_EXEC));
+               reg_eip_aligned_last_valid=reg_eip_aligned;
+               }
        
        /* all instruction notation comments are written in AT&T 'instr src,dest' syntax! */
        if (*reg_eip==0x64) {   /* prefix '%fs:' */
                reg_eip++;
                /* TODO:thread; %fs: is CPU-dependent */
+               if (*reg_eip==0x0F) {   /* two-byte opcode */
+                       reg_eip++;
+                       if (*reg_eip==0xB6) {   /* ??? */
+                               reg_eip++;
+                               if (*reg_eip==0x05) {   /* movzbl %fs:{reg_eip[1..4]},%eax */
+                                       reg_eip++;
+                                       if (instr_mov_fsmem_to_greg(*(const void **)reg_eip,REG_EAX,ucontext)) {
+                                               reg_eip+=4;
+                                               goto ok;
+                                               }
+                                       g_assert_not_reached();
+                                       }
+                               g_assert_not_reached();
+                               }
+                       g_assert_not_reached();
+                       }
                if (*reg_eip==0xA3) {   /* 'mov %eax,%fs:{reg_eip[1..4]}' */
                        reg_eip++;
                        if (instr_mov_greg_to_fsmem(REG_EAX,*(const void **)reg_eip,ucontext)) {
@@ -161,7 +260,7 @@ const void *reg_eip_aligned;
                        }
                if (*reg_eip==0x8B) {   /* prefix 0x8B */
                        reg_eip++;
-                       if ((*reg_eip & ~0x38)==0x05) { /* 'mov %fs:{reg_eip[1..4]},%{op_regcode_to_greg(*reg_eip[b3..b5])} */
+                       if ((*reg_eip & ~0x38)==0x05) { /* 'mov %fs:{reg_eip[1..4]},%{op_regcode_to_greg(*reg_eip[b3..b5])}' */
                                reg_eip++;
                                if (instr_mov_fsmem_to_greg(*(const void **)reg_eip,op_regcode_to_greg(reg_eip[-1]>>3U),ucontext)) {
                                        reg_eip+=4;
@@ -171,8 +270,120 @@ const void *reg_eip_aligned;
                                }
                        g_assert_not_reached();
                        }
+               if (*reg_eip==0xFF) {   /* prefix 0xFF */
+                       reg_eip++;
+                       if (*reg_eip==0x05) {   /* 'incl %fs:{reg_eip[1..4]}' */
+                               reg_eip++;
+                               if (instr_incl_fsmem(*(const void **)reg_eip,ucontext)) {
+                                       reg_eip+=4;
+                                       goto ok;
+                                       }
+                               g_assert_not_reached();
+                               }
+                       if (*reg_eip==0x35) {   /* 'pushl %fs:{reg_eip[1..4]}' */
+                               reg_eip++;
+                               if (instr_push_fsmem(*(const void **)reg_eip,ucontext)) {
+                                       reg_eip+=4;
+                                       goto ok;
+                                       }
+                               g_assert_not_reached();
+                               }
+                       g_assert_not_reached();
+                       }
+               if (*reg_eip==0x8F) {   /* prefix 0x0F */
+                       reg_eip++;
+                       if (*reg_eip==0x05) {   /* 'popl %fs:{reg_eip[1..4]}' */
+                               reg_eip++;
+                               if (instr_pop_fsmem(*(const void **)reg_eip,ucontext)) {
+                                       reg_eip+=4;
+                                       goto ok;
+                                       }
+                               g_assert_not_reached();
+                               }
+                       g_assert_not_reached();
+                       }
+               if (*reg_eip==0xC7) {   /* prefix 0xC7 */
+                       reg_eip++;
+                       if (*reg_eip==0x05) {   /* 'movl ${reg_eip[5..8]},%fs:{reg_eip[1..4]}' */
+                               reg_eip++;
+                               if (instr_mov_immed_to_fsmem(((greg_t *)reg_eip)[1],*(const void **)reg_eip,ucontext)) {
+                                       reg_eip+=4+4;
+                                       goto ok;
+                                       }
+                               g_assert_not_reached();
+                               }
+                       g_assert_not_reached();
+                       }
                g_assert_not_reached();
                }
+
+       /* all instruction notation comments are written in AT&T 'instr src,dest' syntax! */
+       if (*reg_eip==0x66) {   /* prefix '%fs:' */
+               reg_eip++;
+               /* TODO:thread; %fs: is CPU-dependent */
+               if (*reg_eip==0x8E) {   /* two-byte opcode */
+                       reg_eip++;
+                       if (*reg_eip==0xE3) {   /* 'mov %bx,%fs' */
+                               reg_eip++;
+                               g_assert(0x30==(0xFFFF&ucontext->uc_mcontext.gregs[REG_EBX]));
+                               /* 'reload' of %fs can be ignored */
+                               goto ok;
+                               }
+                       g_assert_not_reached();
+                       }
+               g_assert_not_reached();
+               }
+
+       if (*reg_eip==0xF4) {   /* hlt; from captive_ModuleList_patch() */
+struct captive_ModuleList_patchpoint *patchpoint;
+const gchar *funcname_disabled;
+
+               g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"%s: reg_eip=%p; 0xF4 hit",G_STRLOC,reg_eip);
+
+               if ((funcname_disabled=captive_ModuleList_function_disable_find(
+                                               reg_eip)))      { /* ExportAddress */
+                       g_error("%s: Reached disabled W32 function: %s",G_STRLOC,funcname_disabled);
+                       g_assert_not_reached();
+                       }
+               patchpoint=captive_ModuleList_patchpoint_find(
+                               reg_eip);       /* ExportAddress */
+               g_assert(patchpoint!=NULL);
+               if (reg_eip==patchpoint->orig_w32_func) {
+                       g_assert(0xF4 /* hlt */ ==*patchpoint->orig_w32_func);
+                       g_assert(patchpoint->orig_w32_2ndinstr_byte ==*patchpoint->orig_w32_2ndinstr);
+                       if (patchpoint->through_w32_func) {
+                               *patchpoint->orig_w32_func=patchpoint->orig_w32_func_byte;
+                               *patchpoint->orig_w32_2ndinstr=0xF4;    /* hlt */
+                               }
+                       else {  /* !patchpoint->through_w32_func */
+                               reg_eip=(guint8 *)patchpoint->wrap_wrap_func;
+                               }
+                       goto ok;
+                       }
+               if (reg_eip==patchpoint->orig_w32_2ndinstr) {
+                       g_assert(patchpoint->orig_w32_func_byte ==*patchpoint->orig_w32_func);
+                       g_assert(0xF4 /* hlt */ ==*patchpoint->orig_w32_2ndinstr);
+                       g_assert(patchpoint->through_w32_func==TRUE);
+                       *patchpoint->orig_w32_func=0xF4;        /* hlt */
+                       *patchpoint->orig_w32_2ndinstr=patchpoint->orig_w32_2ndinstr_byte;
+                       patchpoint->through_w32_func=FALSE;
+                       goto ok;
+                       }
+               g_assert_not_reached();
+               }
+
+       if (*reg_eip==0xFA) {   /* cli */
+               g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"%s: reg_eip=%p; CLI neutralized",G_STRLOC,reg_eip);
+               *reg_eip=0x90;  /* nop */
+               goto ok;
+               }
+
+       if (*reg_eip==0xFB) {   /* sti */
+               g_log(G_LOG_DOMAIN,G_LOG_LEVEL_DEBUG,"%s: reg_eip=%p; STI neutralized",G_STRLOC,reg_eip);
+               *reg_eip=0x90;  /* nop */
+               goto ok;
+               }
+
        g_assert_not_reached();
 
 ok: