ct_exceptions.m   [plain text]

/*
* Copyright (c) 2018 Apple Inc. All Rights Reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this
* file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_LICENSE_HEADER_END@
*
* ct_exceptions.m
*/

#import <Foundation/Foundation.h>
#include <Security/SecTrustSettingsPriv.h>
#include <Security/SecCertificatePriv.h>
#include <utilities/fileIo.h>
#include <utilities/SecCFWrappers.h>

#include "SecurityCommands.h"

NSString* toolAppID = @"com.apple.security";

static int addCertFile(const char *fileName, NSMutableArray *array) {
SecCertificateRef certRef = NULL;
NSData *data = NULL;
unsigned char *buf = NULL;
size_t numBytes;
int rtn = 0;

if (readFileSizet(fileName, &buf, &numBytes)) {
rtn = -1;
goto errOut;
}

data = [NSData dataWithBytes:buf length:numBytes];
certRef = SecCertificateCreateWithData(NULL, (__bridge CFDataRef)data);
if (!certRef) {
certRef = SecCertificateCreateWithPEM(NULL, (__bridge CFDataRef)data);
if (!certRef) {
rtn = -1;
goto errOut;
}
}

[array addObject:(__bridge id)certRef];

errOut:
/* Cleanup */
free(buf);
CFReleaseNull(certRef);
return rtn;
}

static int returnCFError(CFErrorRef CF_CONSUMED error) {
CFStringRef errorString = CFErrorCopyDescription(error);
CFStringPerformWithCString(errorString, ^(const char *utf8Str) {
fprintf(stderr, "Failed to copy CT exceptions: %s\n", utf8Str);
});
CFIndex errCode = CFErrorGetCode(error);
CFReleaseNull(error);
return (int)errCode;
}

static int resetExceptions(bool resetCerts, bool resetDomains) {
bool result = false;
CFErrorRef error = NULL;
if (resetCerts) {
NSDictionary *resetCertsDict = @{ (__bridge NSString*)kSecCTExceptionsCAsKey: @[] };
result = SecTrustStoreSetCTExceptions(NULL, (__bridge CFDictionaryRef)resetCertsDict, &error);
}
if (!error && resetDomains) {
NSDictionary *resetDomainsDict = @{ (__bridge NSString*)kSecCTExceptionsDomainsKey : @[] };
result = SecTrustStoreSetCTExceptions(NULL, (__bridge CFDictionaryRef)resetDomainsDict, &error);
}
if (!result) {
return returnCFError(error);
}
return 0;
}

static int addExceptions(CFStringRef key, NSArray *newExceptions) {
CFErrorRef error = NULL;
NSDictionary *currentExceptions = CFBridgingRelease(SecTrustStoreCopyCTExceptions((__bridge CFStringRef)toolAppID, &error));
if (!currentExceptions && error) {
return returnCFError(error);
}

NSMutableArray *exceptionsForKey = nil;
if (currentExceptions && currentExceptions[(__bridge NSString*)key]) {
exceptionsForKey = [currentExceptions[(__bridge NSString*)key] mutableCopy];
[exceptionsForKey addObjectsFromArray:newExceptions];
} else {
exceptionsForKey = [newExceptions copy];
}

NSDictionary *newExceptionsDict = @{ (__bridge NSString*)key: exceptionsForKey };
bool result = SecTrustStoreSetCTExceptions(NULL, (__bridge CFDictionaryRef)newExceptionsDict, &error);
if (!result) {
return returnCFError(error);
}

return 0;
}

int add_ct_exceptions(int argc, char * const *argv) {
int arg;

bool resetDomains = false;
bool resetCerts = false;

NSMutableArray *domains = [NSMutableArray array];
NSMutableArray *certs = [NSMutableArray array];
NSDictionary *plist = nil;

/* parse args */
if (argc == 1) {
return SHOW_USAGE_MESSAGE;
}

while ((arg = getopt(argc, argv, "d:c:r:p:")) != -1) {
switch(arg) {
case 'd': {
NSString *domain = [NSString stringWithCString:optarg encoding:NSUTF8StringEncoding];
[domains addObject:domain];
break;
}
case 'c':
if (addCertFile(optarg, certs)) {
fprintf(stderr, "Failed to read cert file\n");
return 1;
}
break;
case 'r':
if (!strcmp(optarg, "all")) {
resetDomains = true;
resetCerts = true;
} else if (!strcmp(optarg, "domain")) {
resetDomains = true;
} else if (!strcmp(optarg, "cert")) {
resetCerts = true;
} else {
return SHOW_USAGE_MESSAGE;
}
break;
case 'p':
plist = [NSDictionary dictionaryWithContentsOfFile:[NSString stringWithCString:optarg encoding:NSUTF8StringEncoding]];
break;
case '?':
default:
return SHOW_USAGE_MESSAGE;
}
}

/* handle reset operation */
if (resetCerts || resetDomains) {
return resetExceptions(resetCerts, resetDomains);
}

/* set plist */
if (plist) {
CFErrorRef error = NULL;
bool result = SecTrustStoreSetCTExceptions(NULL, (__bridge CFDictionaryRef)plist, &error);
if (!result) {
return returnCFError(error);
} else {
return 0;
}
}

/* add domains */
int status = 0;
if ([domains count]) {
status = addExceptions(kSecCTExceptionsDomainsKey, domains);
}
if (status != 0) {
fprintf(stderr, "failed to add domain exceptions\n");
return status;
}

/* add certs */
if ([certs count]) {
NSMutableArray<NSDictionary *>*valuesForCAsKey = [NSMutableArray arrayWithCapacity:[certs count]];
[certs enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
SecCertificateRef cert = (__bridge SecCertificateRef)obj;
NSData* hash = CFBridgingRelease(SecCertificateCopySubjectPublicKeyInfoSHA256Digest(cert));
NSDictionary *value = @{ (__bridge NSString*)kSecCTExceptionsHashAlgorithmKey:@"sha256",
(__bridge NSString*)kSecCTExceptionsSPKIHashKey:hash };
[valuesForCAsKey addObject:value];
}];
status = addExceptions(kSecCTExceptionsCAsKey, valuesForCAsKey);
}
if (status != 0) {
fprintf(stderr, "failed to add cert exceptions\n");
return status;
}

return 0;
}

static int printExceptions(CFStringRef key, NSDictionary *allExceptions) {
if (!allExceptions || !allExceptions[(__bridge NSString*)key] ||
[allExceptions[(__bridge NSString*)key] count] == 0) {
CFStringPerformWithCString(key, ^(const char *utf8Str) {
fprintf(stdout, "No CT Exceptions for %s\n", utf8Str);
});
return 0;
}

NSArray *exceptionsForKey = allExceptions[(__bridge NSString*)key];
NSMutableString *exceptionsString = [NSMutableString stringWithFormat:@"\t%@ : [",key];
[exceptionsForKey enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
if ([obj isKindOfClass:[NSString class]]) {
if (idx == 0) {
[exceptionsString appendFormat:@"\"%@\"",obj];
} else {
[exceptionsString appendFormat:@", \"%@\"", obj];
}
} else if ([obj isKindOfClass:[NSDictionary class]]) {
if (idx == 0) {
[exceptionsString appendString:@"\n\t "];
} else {
[exceptionsString appendString:@"\t "];
}
[exceptionsString appendFormat:@"\"%@:", obj[(__bridge NSString*)kSecCTExceptionsHashAlgorithmKey]];
NSString *hashHex = CFBridgingRelease(CFDataCopyHexString((__bridge CFDataRef)obj[(__bridge NSString*)kSecCTExceptionsSPKIHashKey]));
[exceptionsString appendString:hashHex];
if ([exceptionsForKey count] == idx + 1) { // last entry
[exceptionsString appendString:@"\"\n"];
} else {
[exceptionsString appendString:@"\",\n"];
}
}
}];
[exceptionsString appendString:@"]\n"];
CFStringPerformWithCString((__bridge CFStringRef)exceptionsString, ^(const char *utf8Str) {
fprintf(stdout, "\n%s\n", utf8Str);
});

return 0;
}

int show_ct_exceptions(int argc, char * const *argv) {
int arg;
bool allExceptions = false;
NSString *identifier = nil;
bool domainExceptions = false;
bool certExceptions = false;

/* parse args */
while ((arg = getopt(argc, argv, "ai:dc")) != -1) {
switch(arg) {
case 'a':
allExceptions = true;
break;
case 'i':
identifier = [NSString stringWithCString:optarg encoding:NSUTF8StringEncoding];
break;
case 'd':
domainExceptions = true;
break;
case 'c':
certExceptions = true;
break;
case '?':
default:
return SHOW_USAGE_MESSAGE;
}
}

if (!domainExceptions && !certExceptions) {
/* Nothing specified, show both */
domainExceptions = true;
certExceptions = true;
}

if (allExceptions) {
identifier = nil;
fprintf(stdout, "Showing exceptions for all apps\n");
} else if (!identifier) {
identifier = toolAppID;
}

if (identifier) {
CFStringPerformWithCString((__bridge CFStringRef)identifier, ^(const char *utf8Str) {
fprintf(stdout, "Showing exceptions for %s\n", utf8Str);
});
}

CFErrorRef error = NULL;
NSDictionary *results = CFBridgingRelease(SecTrustStoreCopyCTExceptions((__bridge CFStringRef)identifier, &error));

/* Copy failed, return error */
if (!results && error) {
return returnCFError(error);
}

/* print domain exceptions */
int status = 0;
if (domainExceptions) {
status = printExceptions(kSecCTExceptionsDomainsKey, results);
}
if (status != 0) {
fprintf(stderr, "failed to print domain exceptions\n");
return status;
}

/* print cert exceptions */
if (certExceptions) {
status = printExceptions(kSecCTExceptionsCAsKey, results);
}
if (status != 0) {
fprintf(stderr, "failed to print cert exceptions\n");
return status;
}

return 0;
}