hook: Update capnhook source files from latest master

https://github.com/decafcode/capnhook

src/main/hook/table.c

@@ -1,5 +1,6 @@
 #include <windows.h>
 
+#include <assert.h>
 #include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
@@ -8,32 +9,44 @@
 #include "hook/peb.h"
 #include "hook/table.h"
 
-#include "util/mem.h"
+static const char apiset_prefix[] = "api-ms-win-core-";
+static const size_t apiset_prefix_len = sizeof(apiset_prefix) - 1;
 
 static void hook_table_apply_to_all(
-    const char *depname, const struct hook_symbol *syms, size_t nsyms);
+        const char *depname,
+        const struct hook_symbol *syms,
+        size_t nsyms);
 
 static void hook_table_apply_to_iid(
-    HMODULE target,
-    const pe_iid_t *iid,
-    const struct hook_symbol *syms,
-    size_t nsyms);
+        HMODULE target,
+        const pe_iid_t *iid,
+        const struct hook_symbol *syms,
+        size_t nsyms);
+
+static bool hook_table_match_module(
+        HMODULE target,
+        const char *iid_name,
+        const char *depname);
 
 static bool hook_table_match_proc(
-    const struct pe_iat_entry *iate, const struct hook_symbol *sym);
+        const struct pe_iat_entry *iate,
+        const struct hook_symbol *sym);
 
 static void hook_table_apply_to_all(
-    const char *depname, const struct hook_symbol *syms, size_t nsyms)
+        const char *depname,
+        const struct hook_symbol *syms,
+        size_t nsyms)
 {
     const peb_dll_t *dll;
     HMODULE pe;
 
-    for (dll = peb_dll_get_first(); dll != NULL; dll = peb_dll_get_next(dll)) {
+    for (   dll = peb_dll_get_first() ;
+            dll != NULL ;
+            dll = peb_dll_get_next(dll)) {
         pe = peb_dll_get_base(dll);
 
         if (pe == NULL) {
-            /* wtf? */
-            continue;
+            continue; /* ?? Happens sometimes. */
         }
 
         hook_table_apply(pe, depname, syms, nsyms);
@@ -41,25 +54,29 @@ static void hook_table_apply_to_all(
 }
 
 void hook_table_apply(
-    HMODULE target,
-    const char *depname,
-    const struct hook_symbol *syms,
-    size_t nsyms)
+        HMODULE target,
+        const char *depname,
+        const struct hook_symbol *syms,
+        size_t nsyms)
 {
     const pe_iid_t *iid;
     const char *iid_name;
 
+    assert(depname != NULL);
+    assert(syms != NULL || nsyms == 0);
+
     if (target == NULL) {
         /*  Call out, which will then call us back repeatedly. Awkward, but
             viewed from the outside it's good for usability. */
 
         hook_table_apply_to_all(depname, syms, nsyms);
     } else {
-        for (iid = pe_iid_get_first(target); iid != NULL;
-             iid = pe_iid_get_next(target, iid)) {
+        for (   iid = pe_iid_get_first(target) ;
+                iid != NULL ;
+                iid = pe_iid_get_next(target, iid)) {
             iid_name = pe_iid_get_name(target, iid);
 
-            if (_stricmp(iid_name, depname) == 0) {
+            if (hook_table_match_module(target, iid_name, depname)) {
                 hook_table_apply_to_iid(target, iid, syms, nsyms);
             }
         }
@@ -67,10 +84,10 @@ void hook_table_apply(
 }
 
 static void hook_table_apply_to_iid(
-    HMODULE target,
-    const pe_iid_t *iid,
-    const struct hook_symbol *syms,
-    size_t nsyms)
+        HMODULE target,
+        const pe_iid_t *iid,
+        const struct hook_symbol *syms,
+        size_t nsyms)
 {
     struct pe_iat_entry iate;
     size_t i;
@@ -79,8 +96,8 @@ static void hook_table_apply_to_iid(
 
     i = 0;
 
-    while (pe_iid_get_iat_entry(target, iid, i++, &iate)) {
-        for (j = 0; j < nsyms; j++) {
+    while (pe_iid_get_iat_entry(target, iid, i++, &iate) == S_OK) {
+        for (j = 0 ; j < nsyms ; j++) {
             sym = &syms[j];
 
             if (hook_table_match_proc(&iate, sym)) {
@@ -88,17 +105,70 @@ static void hook_table_apply_to_iid(
                     *sym->link = *iate.ppointer;
                 }
 
-                pe_patch_pointer(iate.ppointer, sym->patch);
+                pe_patch(iate.ppointer, &sym->patch, sizeof(sym->patch));
             }
         }
     }
 }
 
-static bool hook_table_match_proc(
-    const struct pe_iat_entry *iate, const struct hook_symbol *sym)
+static bool hook_table_match_module(
+        HMODULE target,
+        const char *iid_name,
+        const char *depname)
 {
-    if (sym->name != NULL && iate->name != NULL &&
-        strcmp(sym->name, iate->name) == 0) {
+    HMODULE kernel32;
+    int result;
+
+    /* OK, first do a straightforward match on the imported DLL name versus
+       the hook table DLL name. If it succeeds then we're done. */
+
+    result = _stricmp(iid_name, depname);
+
+    if (result == 0) {
+        return true;
+    }
+
+    /* If it failed then we have to check if this hook table targets kernel32.
+       We have to do some special processing around API sets in that case, so
+       stop here if kernel32 is not the subject of this hook table. */
+
+    if (_stricmp(depname, "kernel32.dll") != 0) {
+        return false;
+    }
+
+    /* There isn't really any good test for whether a DLL import wants a
+       concrete DLL or an abstract DLL providing a particular Windows API-set,
+       so we use a hacky check against the prefix. If the imported DLL name
+       looks like an apiset then we'll allow kernel32 hook tables to apply. */
+
+    result = _strnicmp(iid_name, apiset_prefix, apiset_prefix_len);
+
+    if (result != 0) {
+        return false;
+    }
+
+    /* ... EXCEPT for the case where we're hooking all DLLs loaded into the
+       process and we are currently examining kernel32 itself. In that case
+       there's some weird reference loops issues I don't entirely understand
+       right now. To avoid those, we just don't apply kernel32 hook tables to
+       kernel32 itself. */
+
+    kernel32 = GetModuleHandleW(L"kernel32.dll");
+
+    if (target == kernel32) {
+        return false;
+    }
+
+    return true;
+}
+
+static bool hook_table_match_proc(
+        const struct pe_iat_entry *iate,
+        const struct hook_symbol *sym)
+{
+    if (    sym->name != NULL &&
+            iate->name != NULL &&
+            strcmp(sym->name, iate->name) == 0) {
         return true;
     }