#include "Digest_block.h"
#include "SecCustomTransform.h"
#include <CommonCrypto/CommonDigest.h>
#include "Utilities.h"
extern const CFStringRef kSecDigestMD2, kSecDigestMD4, kSecDigestMD5, kSecDigestSHA1, kSecDigestSHA2;
extern const CFStringRef kSecDigestTypeAttribute, kSecDigestLengthAttribute;
static CFStringRef kCustomDigestTransformName = CFSTR("com.apple.security.digest");
SecTransformRef SecDigestTransformCreate_block(SecProviderRef device, CFTypeRef digestType, CFIndex digestLength, CFErrorRef* error) {
static dispatch_once_t inited;
__block CFStringRef current_algo;
__block CFIndex current_length;
dispatch_once(&inited, ^{
SecTransformRegister(kCustomDigestTransformName, ^(CFStringRef name, SecTransformRebindActionBlock rebind) {
rebind(kSecTransformActionProcessData, NULL, ^(SecTransformRef tr, CFDataRef d, SecTransformSendAttribute set) {
set(kSecDigestTypeAttribute, kSecDigestSHA2);
});
rebind(SecTransformSetAttributeAction, NULL, ^(SecTransformRef tr, CFStringRef name, CFTypeRef value, SecTransformSendAttribute set) {
Boolean algo_changed = FALSE;
if (name == kSecDigestTypeAttribute || CFStringCompare(kSecDigestTypeAttribute, name, 0) == kCFCompareEqualTo) {
algo_changed = TRUE;
current_algo = CFStringCreateCopy(NULL, (CFStringRef)value);
} else if (name == kSecDigestLengthAttribute || CFStringCompare(kSecDigestLengthAttribute, name, 0) == kCFCompareEqualTo) {
algo_changed = TRUE;
CFNumberGetValue(value, kCFNumberCFIndexType, ¤t_length);
} else if (CFStringCompare(kSecTransformInputAttributeName, name, 0) == kCFCompareEqualTo) {
return (CFTypeRef)CreateSecTransformErrorRef(kSecTransformErrorInvalidType, "The type %@ is invalid.", name);
} else {
return (CFTypeRef)CreateSecTransformErrorRef(kSecTransformErrorInvalidType, "The type %@ is invalid.", name);
}
if (!algo_changed) {
return value;
}
if (current_algo == kSecDigestSHA2 || CFStringCompare(current_algo, kSecDigestSHA2, 0) == kCFCompareEqualTo) {
switch (current_length) {
case 0:
case 512: {
__block CC_SHA512_CTX cc_context;
CC_SHA512_Init(&cc_context);
rebind(kSecTransformActionProcessData, NULL, ^(SecTransformRef tr, CFDataRef d, SecTransformSendAttribute set) {
if (d) {
CC_SHA512_Update(&cc_context, CFDataGetBytePtr(d), CFDataGetLength(d));
return SecTransformNoData();
} else {
u_int8_t digest_buffer[CC_SHA512_DIGEST_LENGTH];
CC_SHA512_Final(digest_buffer, &cc_context);
set(kSecTransformOutputAttributeName, CFDataCreate(NULL, digest_buffer, CC_SHA512_DIGEST_LENGTH));
return NULL;
}
});
return value;
}
}
return (CFTypeRef)CreateSecTransformErrorRef(kSecTransformErrorInvalidLength, "Invalid length.");
} else {
return (CFTypeRef)CreateSecTransformErrorRef(kSecTransformErrorInvalidAlgorithm, "Invalid algorithm.");
}
});
}, NULL);
});
SecTransformRef dt = SecTransformCreate(kCustomDigestTransformName, NULL);
SecTransformSetAttribute(dt, kSecDigestTypeAttribute, digestType, error);
CFNumberRef dlen = CFNumberCreate(NULL, kCFNumberCFIndexType, &digestLength);
SecTransformSetAttribute(dt, kSecDigestLengthAttribute, dlen, error);
CFRelease(dlen);
return dt;
}