gecko-dev/modules/libmar/verify/mar_verify.c

467 строки
15 KiB
C

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifdef XP_WIN
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include "mar_private.h"
#include "mar.h"
#include "cryptox.h"
int
mar_read_entire_file(const char * filePath, uint32_t maxSize,
/*out*/ const uint8_t * *data,
/*out*/ uint32_t *size)
{
int result;
FILE * f;
if (!filePath || !data || !size) {
return -1;
}
f = fopen(filePath, "rb");
if (!f) {
return -1;
}
result = -1;
if (!fseeko(f, 0, SEEK_END)) {
int64_t fileSize = ftello(f);
if (fileSize > 0 && fileSize <= maxSize && !fseeko(f, 0, SEEK_SET)) {
unsigned char * fileData;
*size = (unsigned int) fileSize;
fileData = malloc(*size);
if (fileData) {
if (fread(fileData, *size, 1, f) == 1) {
*data = fileData;
result = 0;
} else {
free(fileData);
}
}
}
}
fclose(f);
return result;
}
int mar_extract_and_verify_signatures_fp(FILE *fp,
CryptoX_ProviderHandle provider,
CryptoX_PublicKey *keys,
uint32_t keyCount);
int mar_verify_signatures_for_fp(FILE *fp,
CryptoX_ProviderHandle provider,
CryptoX_PublicKey *keys,
const uint8_t * const *extractedSignatures,
uint32_t keyCount,
uint32_t *numVerified);
/**
* Reads the specified number of bytes from the file pointer and
* stores them in the passed buffer.
*
* @param fp The file pointer to read from.
* @param buffer The buffer to store the read results.
* @param size The number of bytes to read, buffer must be
* at least of this size.
* @param ctxs Pointer to the first element in an array of verify context.
* @param count The number of elements in ctxs
* @param err The name of what is being written to in case of error.
* @return 0 on success
* -1 on read error
* -2 on verify update error
*/
int
ReadAndUpdateVerifyContext(FILE *fp,
void *buffer,
uint32_t size,
CryptoX_SignatureHandle *ctxs,
uint32_t count,
const char *err)
{
uint32_t k;
if (!fp || !buffer || !ctxs || count == 0 || !err) {
fprintf(stderr, "ERROR: Invalid parameter specified.\n");
return CryptoX_Error;
}
if (!size) {
return CryptoX_Success;
}
if (fread(buffer, size, 1, fp) != 1) {
fprintf(stderr, "ERROR: Could not read %s\n", err);
return CryptoX_Error;
}
for (k = 0; k < count; k++) {
if (CryptoX_Failed(CryptoX_VerifyUpdate(&ctxs[k], buffer, size))) {
fprintf(stderr, "ERROR: Could not update verify context for %s\n", err);
return -2;
}
}
return CryptoX_Success;
}
/**
* Verifies a MAR file by verifying each signature with the corresponding
* certificate. That is, the first signature will be verified using the first
* certificate given, the second signature will be verified using the second
* certificate given, etc. The signature count must exactly match the number of
* certificates given, and all signature verifications must succeed.
*
* @param mar The file who's signature should be calculated
* @param certData Pointer to the first element in an array of
* certificate data
* @param certDataSizes Pointer to the first element in an array for size of
* the data stored
* @param certCount The number of elements in certData and certDataSizes
* @return 0 on success
*/
int
mar_verify_signatures(MarFile *mar,
const uint8_t * const *certData,
const uint32_t *certDataSizes,
uint32_t certCount) {
int rv = -1;
CryptoX_ProviderHandle provider = CryptoX_InvalidHandleValue;
CryptoX_PublicKey keys[MAX_SIGNATURES];
uint32_t k;
memset(keys, 0, sizeof(keys));
if (!mar || !certData || !certDataSizes || certCount == 0) {
fprintf(stderr, "ERROR: Invalid parameter specified.\n");
goto failure;
}
if (!mar->fp) {
fprintf(stderr, "ERROR: MAR file is not open.\n");
goto failure;
}
if (CryptoX_Failed(CryptoX_InitCryptoProvider(&provider))) {
fprintf(stderr, "ERROR: Could not init crytpo library.\n");
goto failure;
}
for (k = 0; k < certCount; ++k) {
if (CryptoX_Failed(CryptoX_LoadPublicKey(provider, certData[k], certDataSizes[k],
&keys[k]))) {
fprintf(stderr, "ERROR: Could not load public key.\n");
goto failure;
}
}
rv = mar_extract_and_verify_signatures_fp(mar->fp, provider, keys, certCount);
failure:
for (k = 0; k < certCount; ++k) {
if (keys[k]) {
CryptoX_FreePublicKey(&keys[k]);
}
}
return rv;
}
/**
* Extracts each signature from the specified MAR file,
* then calls mar_verify_signatures_for_fp to verify each signature.
*
* @param fp An opened MAR file handle
* @param provider A library provider
* @param keys The public keys to use to verify the MAR
* @param keyCount The number of keys pointed to by keys
* @return 0 on success
*/
int
mar_extract_and_verify_signatures_fp(FILE *fp,
CryptoX_ProviderHandle provider,
CryptoX_PublicKey *keys,
uint32_t keyCount) {
uint32_t signatureCount, signatureLen, numVerified = 0;
uint32_t signatureAlgorithmIDs[MAX_SIGNATURES];
uint8_t *extractedSignatures[MAX_SIGNATURES];
uint32_t i;
memset(signatureAlgorithmIDs, 0, sizeof(signatureAlgorithmIDs));
memset(extractedSignatures, 0, sizeof(extractedSignatures));
if (!fp) {
fprintf(stderr, "ERROR: Invalid file pointer passed.\n");
return CryptoX_Error;
}
/* To protect against invalid MAR files, we assumes that the MAR file
size is less than or equal to MAX_SIZE_OF_MAR_FILE. */
if (fseeko(fp, 0, SEEK_END)) {
fprintf(stderr, "ERROR: Could not seek to the end of the MAR file.\n");
return CryptoX_Error;
}
if (ftello(fp) > MAX_SIZE_OF_MAR_FILE) {
fprintf(stderr, "ERROR: MAR file is too large to be verified.\n");
return CryptoX_Error;
}
/* Skip to the start of the signature block */
if (fseeko(fp, SIGNATURE_BLOCK_OFFSET, SEEK_SET)) {
fprintf(stderr, "ERROR: Could not seek to the signature block.\n");
return CryptoX_Error;
}
/* Get the number of signatures */
if (fread(&signatureCount, sizeof(signatureCount), 1, fp) != 1) {
fprintf(stderr, "ERROR: Could not read number of signatures.\n");
return CryptoX_Error;
}
signatureCount = ntohl(signatureCount);
/* Check that we have less than the max amount of signatures so we don't
waste too much of either updater's or signmar's time. */
if (signatureCount > MAX_SIGNATURES) {
fprintf(stderr, "ERROR: At most %d signatures can be specified.\n",
MAX_SIGNATURES);
return CryptoX_Error;
}
for (i = 0; i < signatureCount; i++) {
/* Get the signature algorithm ID */
if (fread(&signatureAlgorithmIDs[i], sizeof(uint32_t), 1, fp) != 1) {
fprintf(stderr, "ERROR: Could not read signatures algorithm ID.\n");
return CryptoX_Error;
}
signatureAlgorithmIDs[i] = ntohl(signatureAlgorithmIDs[i]);
if (fread(&signatureLen, sizeof(uint32_t), 1, fp) != 1) {
fprintf(stderr, "ERROR: Could not read signatures length.\n");
return CryptoX_Error;
}
signatureLen = ntohl(signatureLen);
/* To protected against invalid input make sure the signature length
isn't too big. */
if (signatureLen > MAX_SIGNATURE_LENGTH) {
fprintf(stderr, "ERROR: Signature length is too large to verify.\n");
return CryptoX_Error;
}
extractedSignatures[i] = malloc(signatureLen);
if (!extractedSignatures[i]) {
fprintf(stderr, "ERROR: Could allocate buffer for signature.\n");
return CryptoX_Error;
}
if (fread(extractedSignatures[i], signatureLen, 1, fp) != 1) {
fprintf(stderr, "ERROR: Could not read extracted signature.\n");
for (i = 0; i < signatureCount; ++i) {
free(extractedSignatures[i]);
}
return CryptoX_Error;
}
/* We don't try to verify signatures we don't know about */
if (signatureAlgorithmIDs[i] != 1) {
fprintf(stderr, "ERROR: Unknown signature algorithm ID.\n");
for (i = 0; i < signatureCount; ++i) {
free(extractedSignatures[i]);
}
return CryptoX_Error;
}
}
if (ftello(fp) == -1) {
return CryptoX_Error;
}
if (mar_verify_signatures_for_fp(fp,
provider,
keys,
(const uint8_t * const *)extractedSignatures,
signatureCount,
&numVerified) == CryptoX_Error) {
return CryptoX_Error;
}
for (i = 0; i < signatureCount; ++i) {
free(extractedSignatures[i]);
}
/* If we reached here and we verified every
signature, return success. */
if (numVerified == signatureCount && keyCount == numVerified) {
return CryptoX_Success;
}
if (numVerified == 0) {
fprintf(stderr, "ERROR: Not all signatures were verified.\n");
} else {
fprintf(stderr, "ERROR: Only %d of %d signatures were verified.\n",
numVerified, signatureCount);
}
return CryptoX_Error;
}
/**
* Verifies a MAR file by verifying each signature with the corresponding
* certificate. That is, the first signature will be verified using the first
* certificate given, the second signature will be verified using the second
* certificate given, etc. The signature count must exactly match the number of
* certificates given, and all signature verifications must succeed.
*
* @param fp An opened MAR file handle
* @param provider A library provider
* @param keys A pointer to the first element in an
* array of keys.
* @param extractedSignatures Pointer to the first element in an array
* of extracted signatures.
* @param signatureCount The number of signatures in the MAR file
* @param numVerified Out parameter which will be filled with
* the number of verified signatures.
* This information can be useful for printing
* error messages.
* @return 0 on success, *numVerified == signatureCount.
*/
int
mar_verify_signatures_for_fp(FILE *fp,
CryptoX_ProviderHandle provider,
CryptoX_PublicKey *keys,
const uint8_t * const *extractedSignatures,
uint32_t signatureCount,
uint32_t *numVerified)
{
CryptoX_SignatureHandle signatureHandles[MAX_SIGNATURES];
char buf[BLOCKSIZE];
uint32_t signatureLengths[MAX_SIGNATURES];
uint32_t i;
int rv = CryptoX_Error;
memset(signatureHandles, 0, sizeof(signatureHandles));
memset(signatureLengths, 0, sizeof(signatureLengths));
if (!extractedSignatures || !numVerified) {
fprintf(stderr, "ERROR: Invalid parameter specified.\n");
goto failure;
}
*numVerified = 0;
/* This function is only called when we have at least one signature,
but to protected against future people who call this function we
make sure a non zero value is passed in.
*/
if (!signatureCount) {
fprintf(stderr, "ERROR: There must be at least one signature.\n");
goto failure;
}
for (i = 0; i < signatureCount; i++) {
if (CryptoX_Failed(CryptoX_VerifyBegin(provider,
&signatureHandles[i], &keys[i]))) {
fprintf(stderr, "ERROR: Could not initialize signature handle.\n");
goto failure;
}
}
/* Skip to the start of the file */
if (fseeko(fp, 0, SEEK_SET)) {
fprintf(stderr, "ERROR: Could not seek to start of the file\n");
goto failure;
}
/* Bytes 0-3: MAR1
Bytes 4-7: index offset
Bytes 8-15: size of entire MAR
*/
if (CryptoX_Failed(ReadAndUpdateVerifyContext(fp, buf,
SIGNATURE_BLOCK_OFFSET +
sizeof(uint32_t),
signatureHandles,
signatureCount,
"signature block"))) {
goto failure;
}
/* Read the signature block */
for (i = 0; i < signatureCount; i++) {
/* Get the signature algorithm ID */
if (CryptoX_Failed(ReadAndUpdateVerifyContext(fp,
&buf,
sizeof(uint32_t),
signatureHandles,
signatureCount,
"signature algorithm ID"))) {
goto failure;
}
if (CryptoX_Failed(ReadAndUpdateVerifyContext(fp,
&signatureLengths[i],
sizeof(uint32_t),
signatureHandles,
signatureCount,
"signature length"))) {
goto failure;
}
signatureLengths[i] = ntohl(signatureLengths[i]);
if (signatureLengths[i] > MAX_SIGNATURE_LENGTH) {
fprintf(stderr, "ERROR: Embedded signature length is too large.\n");
goto failure;
}
/* Skip past the signature itself as those are not included */
if (fseeko(fp, signatureLengths[i], SEEK_CUR)) {
fprintf(stderr, "ERROR: Could not seek past signature.\n");
goto failure;
}
}
/* Read the rest of the file after the signature block */
while (!feof(fp)) {
int numRead = fread(buf, 1, BLOCKSIZE , fp);
if (ferror(fp)) {
fprintf(stderr, "ERROR: Error reading data block.\n");
goto failure;
}
for (i = 0; i < signatureCount; i++) {
if (CryptoX_Failed(CryptoX_VerifyUpdate(&signatureHandles[i],
buf, numRead))) {
fprintf(stderr, "ERROR: Error updating verify context with"
" data block.\n");
goto failure;
}
}
}
/* Verify the signatures */
for (i = 0; i < signatureCount; i++) {
if (CryptoX_Failed(CryptoX_VerifySignature(&signatureHandles[i],
&keys[i],
extractedSignatures[i],
signatureLengths[i]))) {
fprintf(stderr, "ERROR: Error verifying signature.\n");
goto failure;
}
++*numVerified;
}
rv = CryptoX_Success;
failure:
for (i = 0; i < signatureCount; i++) {
CryptoX_FreeSignatureHandle(&signatureHandles[i]);
}
return rv;
}