Add substituted and fix things up to use it. Still untested.

1 files changed, 173 insertions, 0 deletions

diff --git a/darwin-bootstrap/substituted-plist-loader.m b/darwin-bootstrap/substituted-plist-loader.m
new file mode 100644
index 0000000..0c8d66f
--- /dev/null
+++ b/darwin-bootstrap/substituted-plist-loader.m
@@ -0,0 +1,173 @@
+#import <Foundation/Foundation.h>
+#import <CoreFoundation/CoreFoundation.h>
+#include "substituted-messages.h"
+
+enum convert_filters_ret {
+    PROVISIONAL_PASS,
+    FAIL,
+    INVALID
+};
+
+static double id_to_double(id o) {
+    if ([o isKindOfClass:[NSString class]]) {
+        NSScanner *scan = [NSScanner scannerWithString:o];
+        double d;
+        if (![scan scanDouble:&d] || !scan.atEnd)
+            return NAN;
+        return d;
+    } else if ([o isKindOfClass:[NSNumber class]]) {
+        return [o doubleValue];
+    } else {
+        return NAN;
+    }
+}
+
+static enum convert_filters_ret convert_filters(NSDictionary *plist_dict,
+                                                const char *exec_name,
+                                                NSMutableData *test_out) {
+
+    NSDictionary *filter = [plist_dict objectForKey:@"Filter"];
+    if (!filter)
+        return PROVISIONAL_PASS;
+    if (![filter isKindOfClass:[NSDictionary class]])
+        return INVALID;
+
+    for (NSString *key in [filter allKeys]) {
+        if (!([key isEqualToString:@"CoreFoundationVersion"] ||
+              [key isEqualToString:@"Classes"] ||
+              [key isEqualToString:@"Bundles"] ||
+              [key isEqualToString:@"Executables"])) {
+            return INVALID;
+        }
+    }
+
+    /* First do the two we can test here. */
+
+    NSArray *cfv = [filter objectForKey:@"CoreFoundationVersion"];
+    if (cfv) {
+        if (![cfv isKindOfClass:[NSArray class]] ||
+            [cfv count] == 0 ||
+            [cfv count] > 2)
+            return INVALID;
+        double version = kCFCoreFoundationVersionNumber;
+        double minimum = id_to_double([cfv objectAtIndex:0]);
+        if (minimum != minimum)
+            return INVALID;
+        if (version < minimum)
+            return FAIL;
+        id supremum_o = [cfv objectAtIndex:1];
+        if (supremum_o) {
+            double supremum = id_to_double(supremum_o);
+            if (supremum != supremum)
+                return INVALID;
+            if (version >= supremum)
+                return FAIL;
+        }
+    }
+
+    NSArray *executables = [filter objectForKey:@"Executables"];
+    if (executables) {
+        NSString *exe = [NSString stringWithCString:exec_name
+                                  encoding:NSUTF8StringEncoding];
+        if (![executables isKindOfClass:[NSArray class]])
+            return INVALID;
+        for (NSString *name in executables) {
+            if (![name isKindOfClass:[NSString class]])
+                return INVALID;
+            if ([name isEqualToString:exe])
+                goto ok;
+        }
+        return FAIL;
+    ok:;
+    }
+
+    /* Convert the rest to substituted_bundle_list_ops. */
+
+    struct {
+        __unsafe_unretained NSString *key;
+        uint8_t opc;
+    } types[2] = {
+        {@"Classes", SUBSTITUTED_TEST_CLASS},
+        {@"Bundles", SUBSTITUTED_TEST_BUNDLE},
+    };
+
+    for (int i = 0; i < 2; i++) {
+        NSArray *things = [filter objectForKey:types[i].key];
+        if (things) {
+            if (![things isKindOfClass:[NSArray class]])
+                return INVALID;
+            for (NSString *name in things) {
+                if (![name isKindOfClass:[NSString class]])
+                    return INVALID;
+                NSData *name_data = [name dataUsingEncoding:NSUTF8StringEncoding];
+                size_t len = [name_data length];
+                if (len > 65535)
+                    return INVALID;
+                struct substituted_bundle_list_op op = {(uint16_t) len,
+                                                        types[i].opc};
+                [test_out appendBytes:&op length:sizeof(op)];
+                [test_out appendData:name_data];
+                static char zero = '\0';
+                [test_out appendBytes:&zero length:1];
+            }
+        }
+    }
+
+    return PROVISIONAL_PASS;
+}
+
+static NSData *the_bundle_list;
+
+void get_bundle_list(const char *exec_name,
+                     const void **bundle_list, size_t *bundle_list_size) {
+    /* TODO cache */
+    NSError *err;
+    NSString *base = @"/Library/Substitute/DynamicLibraries";
+    NSArray *list = [[NSFileManager defaultManager]
+                     contentsOfDirectoryAtPath:base
+                     error:&err];
+    if (!list)
+        return;
+
+    NSMutableData *out = [NSMutableData data];
+
+    for (NSString *dylib in list) {
+        if (![[dylib pathExtension] isEqualToString:@"dylib"])
+            continue;
+        NSString *plist = [[dylib stringByDeletingPathExtension]
+                           stringByAppendingPathExtension:@"plist"];
+        NSString *full_plist = [base stringByAppendingPathComponent:plist];
+        NSDictionary *plist_dict = [NSDictionary dictionaryWithContentsOfFile:
+                                    full_plist];
+        if (!plist_dict) {
+            NSLog(@"missing, unreadable, or invalid plist '%@' for dylib '%@'; unlike Substrate, we require plists", full_plist, dylib);
+            continue;
+        }
+
+        NSMutableData *test = [NSMutableData data];
+        enum convert_filters_ret ret = convert_filters(plist_dict, exec_name, test);
+        if (ret == FAIL) {
+            continue;
+        } else if (ret == INVALID) {
+            NSLog(@"bad data in plist '%@' for dylib '%@'", full_plist, dylib);
+            continue;
+        }
+        NSString *dylib_path = [base stringByAppendingPathComponent:dylib];
+        NSData *dylib_path_data = [dylib_path dataUsingEncoding:NSUTF8StringEncoding];
+        size_t len = [dylib_path length];
+        if (len > 65535) {
+            NSLog(@"dylib '%@' somehow has an absurdly long path", dylib);
+            continue;
+        }
+        [out appendData:test];
+        struct substituted_bundle_list_op op = {(uint16_t) len,
+                                                SUBSTITUTED_USE_DYLIB};
+        [out appendBytes:&op length:sizeof(op)];
+        [out appendData:dylib_path_data];
+        static char zero = '\0';
+        [out appendBytes:&zero length:1];
+    }
+    the_bundle_list = out;
+    *bundle_list = [out bytes];
+    *bundle_list_size = [out length];
+}