gecko-dev/modules/libmar/sign/mar_sign.c
Sylvestre Ledru 49c4fc149d Bug 1563903 - Reformat libmar to the coding style r=Ehsan
Depends on D37152

Differential Revision: https://phabricator.services.mozilla.com/D37153

--HG--
extra : moz-landing-system : lando
2019-07-08 15:38:50 +00:00

1131 lines
33 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_cmdline.h"
#include "mar.h"
#include "cryptox.h"
#ifndef XP_WIN
# include <unistd.h>
#endif
#include "nss_secutil.h"
#include "base64.h"
/**
* Initializes the NSS context.
*
* @param NSSConfigDir The config dir containing the private key to use
* @return 0 on success
* -1 on error
*/
int NSSInitCryptoContext(const char* NSSConfigDir) {
SECStatus status =
NSS_Initialize(NSSConfigDir, "", "", SECMOD_DB, NSS_INIT_READONLY);
if (SECSuccess != status) {
fprintf(stderr, "ERROR: Could not initialize NSS\n");
return -1;
}
return 0;
}
/**
* Obtains a signing context.
*
* @param ctx A pointer to the signing context to fill
* @return 0 on success
* -1 on error
*/
int NSSSignBegin(const char* certName, SGNContext** ctx,
SECKEYPrivateKey** privKey, CERTCertificate** cert,
uint32_t* signatureLength) {
secuPWData pwdata = {PW_NONE, 0};
if (!certName || !ctx || !privKey || !cert || !signatureLength) {
fprintf(stderr, "ERROR: Invalid parameter passed to NSSSignBegin\n");
return -1;
}
/* Get the cert and embedded public key out of the database */
*cert = PK11_FindCertFromNickname(certName, &pwdata);
if (!*cert) {
fprintf(stderr, "ERROR: Could not find cert from nickname\n");
return -1;
}
/* Get the private key out of the database */
*privKey = PK11_FindKeyByAnyCert(*cert, &pwdata);
if (!*privKey) {
fprintf(stderr, "ERROR: Could not find private key\n");
return -1;
}
*signatureLength = PK11_SignatureLen(*privKey);
if (*signatureLength > BLOCKSIZE) {
fprintf(stderr,
"ERROR: Program must be compiled with a larger block size"
" to support signing with signatures this large: %u.\n",
*signatureLength);
return -1;
}
/* Check that the key length is large enough for our requirements */
if (*signatureLength < XP_MIN_SIGNATURE_LEN_IN_BYTES) {
fprintf(stderr, "ERROR: Key length must be >= %d bytes\n",
XP_MIN_SIGNATURE_LEN_IN_BYTES);
return -1;
}
*ctx = SGN_NewContext(SEC_OID_PKCS1_SHA384_WITH_RSA_ENCRYPTION, *privKey);
if (!*ctx) {
fprintf(stderr, "ERROR: Could not create signature context\n");
return -1;
}
if (SGN_Begin(*ctx) != SECSuccess) {
fprintf(stderr, "ERROR: Could not begin signature\n");
return -1;
}
return 0;
}
/**
* Writes the passed buffer to the file fp and updates the signature contexts.
*
* @param fpDest The file pointer to write to.
* @param buffer The buffer to write.
* @param size The size of the buffer to write.
* @param ctxs Pointer to the first element in an array of signature
* contexts to update.
* @param ctxCount The number of signature contexts pointed to by ctxs
* @param err The name of what is being written to in case of error.
* @return 0 on success
* -2 on write error
* -3 on signature update error
*/
int WriteAndUpdateSignatures(FILE* fpDest, void* buffer, uint32_t size,
SGNContext** ctxs, uint32_t ctxCount,
const char* err) {
uint32_t k;
if (!size) {
return 0;
}
if (fwrite(buffer, size, 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write %s\n", err);
return -2;
}
for (k = 0; k < ctxCount; ++k) {
if (SGN_Update(ctxs[k], buffer, size) != SECSuccess) {
fprintf(stderr, "ERROR: Could not update signature context for %s\n",
err);
return -3;
}
}
return 0;
}
/**
* Adjusts each entry's content offset in the the passed in index by the
* specified amount.
*
* @param indexBuf A buffer containing the MAR index
* @param indexLength The length of the MAR index
* @param offsetAmount The amount to adjust each index entry by
*/
void AdjustIndexContentOffsets(char* indexBuf, uint32_t indexLength,
uint32_t offsetAmount) {
uint32_t* offsetToContent;
char* indexBufLoc = indexBuf;
/* Consume the index and adjust each index by the specified amount */
while (indexBufLoc != (indexBuf + indexLength)) {
/* Adjust the offset */
offsetToContent = (uint32_t*)indexBufLoc;
*offsetToContent = ntohl(*offsetToContent);
*offsetToContent += offsetAmount;
*offsetToContent = htonl(*offsetToContent);
/* Skip past the offset, length, and flags */
indexBufLoc += 3 * sizeof(uint32_t);
indexBufLoc += strlen(indexBufLoc) + 1;
}
}
/**
* Reads from fpSrc, writes it to fpDest, and updates the signature contexts.
*
* @param fpSrc The file pointer to read from.
* @param fpDest The file pointer to write to.
* @param buffer The buffer to write.
* @param size The size of the buffer to write.
* @param ctxs Pointer to the first element in an array of signature
* contexts to update.
* @param ctxCount The number of signature contexts pointed to by 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 write error
* -3 on signature update error
*/
int ReadWriteAndUpdateSignatures(FILE* fpSrc, FILE* fpDest, void* buffer,
uint32_t size, SGNContext** ctxs,
uint32_t ctxCount, const char* err) {
if (!size) {
return 0;
}
if (fread(buffer, size, 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could not read %s\n", err);
return -1;
}
return WriteAndUpdateSignatures(fpDest, buffer, size, ctxs, ctxCount, err);
}
/**
* Reads from fpSrc, writes it to fpDest.
*
* @param fpSrc The file pointer to read from.
* @param fpDest The file pointer to write to.
* @param buffer The buffer to write.
* @param size The size of the buffer to write.
* @param err The name of what is being written to in case of error.
* @return 0 on success
* -1 on read error
* -2 on write error
*/
int ReadAndWrite(FILE* fpSrc, FILE* fpDest, void* buffer, uint32_t size,
const char* err) {
if (!size) {
return 0;
}
if (fread(buffer, size, 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could not read %s\n", err);
return -1;
}
if (fwrite(buffer, size, 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write %s\n", err);
return -2;
}
return 0;
}
/**
* Writes out a copy of the MAR at src but with the signature block stripped.
*
* @param src The path of the source MAR file
* @param dest The path of the MAR file to write out that
has no signature block
* @return 0 on success
* -1 on error
*/
int strip_signature_block(const char* src, const char* dest) {
uint32_t offsetToIndex, dstOffsetToIndex, indexLength, numSignatures = 0,
leftOver;
int32_t stripAmount = 0;
int64_t oldPos, numChunks, i, realSizeOfSrcMAR, numBytesToCopy,
sizeOfEntireMAR = 0;
FILE *fpSrc = NULL, *fpDest = NULL;
int rv = -1, hasSignatureBlock;
char buf[BLOCKSIZE];
char* indexBuf = NULL;
if (!src || !dest) {
fprintf(stderr, "ERROR: Invalid parameter passed in.\n");
return -1;
}
fpSrc = fopen(src, "rb");
if (!fpSrc) {
fprintf(stderr, "ERROR: could not open source file: %s\n", src);
goto failure;
}
fpDest = fopen(dest, "wb");
if (!fpDest) {
fprintf(stderr, "ERROR: could not create target file: %s\n", dest);
goto failure;
}
/* Determine if the source MAR file has the new fields for signing or not */
if (get_mar_file_info(src, &hasSignatureBlock, NULL, NULL, NULL, NULL)) {
fprintf(stderr, "ERROR: could not determine if MAR is old or new.\n");
goto failure;
}
/* MAR ID */
if (ReadAndWrite(fpSrc, fpDest, buf, MAR_ID_SIZE, "MAR ID")) {
goto failure;
}
/* Offset to index */
if (fread(&offsetToIndex, sizeof(offsetToIndex), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could not read offset\n");
goto failure;
}
offsetToIndex = ntohl(offsetToIndex);
/* Get the real size of the MAR */
oldPos = ftello(fpSrc);
if (fseeko(fpSrc, 0, SEEK_END)) {
fprintf(stderr, "ERROR: Could not seek to end of file.\n");
goto failure;
}
realSizeOfSrcMAR = ftello(fpSrc);
if (fseeko(fpSrc, oldPos, SEEK_SET)) {
fprintf(stderr, "ERROR: Could not seek back to current location.\n");
goto failure;
}
if (hasSignatureBlock) {
/* Get the MAR length and adjust its size */
if (fread(&sizeOfEntireMAR, sizeof(sizeOfEntireMAR), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could read mar size\n");
goto failure;
}
sizeOfEntireMAR = NETWORK_TO_HOST64(sizeOfEntireMAR);
if (sizeOfEntireMAR != realSizeOfSrcMAR) {
fprintf(stderr, "ERROR: Source MAR is not of the right size\n");
goto failure;
}
/* Get the num signatures in the source file so we know what to strip */
if (fread(&numSignatures, sizeof(numSignatures), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could read num signatures\n");
goto failure;
}
numSignatures = ntohl(numSignatures);
for (i = 0; i < numSignatures; i++) {
uint32_t signatureLen;
/* Skip past the signature algorithm ID */
if (fseeko(fpSrc, sizeof(uint32_t), SEEK_CUR)) {
fprintf(stderr, "ERROR: Could not skip past signature algorithm ID\n");
}
/* Read in the length of the signature so we know how far to skip */
if (fread(&signatureLen, sizeof(uint32_t), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could not read signatures length.\n");
return CryptoX_Error;
}
signatureLen = ntohl(signatureLen);
/* Skip past the signature */
if (fseeko(fpSrc, signatureLen, SEEK_CUR)) {
fprintf(stderr, "ERROR: Could not skip past signature algorithm ID\n");
}
stripAmount += sizeof(uint32_t) + sizeof(uint32_t) + signatureLen;
}
} else {
sizeOfEntireMAR = realSizeOfSrcMAR;
numSignatures = 0;
}
if (((int64_t)offsetToIndex) > sizeOfEntireMAR) {
fprintf(stderr, "ERROR: Offset to index is larger than the file size.\n");
goto failure;
}
dstOffsetToIndex = offsetToIndex;
if (!hasSignatureBlock) {
dstOffsetToIndex += sizeof(sizeOfEntireMAR) + sizeof(numSignatures);
}
dstOffsetToIndex -= stripAmount;
/* Write out the index offset */
dstOffsetToIndex = htonl(dstOffsetToIndex);
if (fwrite(&dstOffsetToIndex, sizeof(dstOffsetToIndex), 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write offset to index\n");
goto failure;
}
dstOffsetToIndex = ntohl(dstOffsetToIndex);
/* Write out the new MAR file size */
if (!hasSignatureBlock) {
sizeOfEntireMAR += sizeof(sizeOfEntireMAR) + sizeof(numSignatures);
}
sizeOfEntireMAR -= stripAmount;
/* Write out the MAR size */
sizeOfEntireMAR = HOST_TO_NETWORK64(sizeOfEntireMAR);
if (fwrite(&sizeOfEntireMAR, sizeof(sizeOfEntireMAR), 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write size of MAR\n");
goto failure;
}
sizeOfEntireMAR = NETWORK_TO_HOST64(sizeOfEntireMAR);
/* Write out the number of signatures, which is 0 */
numSignatures = 0;
if (fwrite(&numSignatures, sizeof(numSignatures), 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write out num signatures\n");
goto failure;
}
/* Write out the rest of the MAR excluding the index header and index
offsetToIndex unfortunately has to remain 32-bit because for backwards
compatibility with the old MAR file format. */
if (ftello(fpSrc) > ((int64_t)offsetToIndex)) {
fprintf(stderr, "ERROR: Index offset is too small.\n");
goto failure;
}
numBytesToCopy = ((int64_t)offsetToIndex) - ftello(fpSrc);
numChunks = numBytesToCopy / BLOCKSIZE;
leftOver = numBytesToCopy % BLOCKSIZE;
/* Read each file and write it to the MAR file */
for (i = 0; i < numChunks; ++i) {
if (ReadAndWrite(fpSrc, fpDest, buf, BLOCKSIZE, "content block")) {
goto failure;
}
}
/* Write out the left over */
if (ReadAndWrite(fpSrc, fpDest, buf, leftOver, "left over content block")) {
goto failure;
}
/* Length of the index */
if (ReadAndWrite(fpSrc, fpDest, &indexLength, sizeof(indexLength),
"index length")) {
goto failure;
}
indexLength = ntohl(indexLength);
/* Consume the index and adjust each index by the difference */
indexBuf = malloc(indexLength);
if (fread(indexBuf, indexLength, 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could not read index\n");
goto failure;
}
/* Adjust each entry in the index */
if (hasSignatureBlock) {
AdjustIndexContentOffsets(indexBuf, indexLength, -stripAmount);
} else {
AdjustIndexContentOffsets(
indexBuf, indexLength,
sizeof(sizeOfEntireMAR) + sizeof(numSignatures) - stripAmount);
}
if (fwrite(indexBuf, indexLength, 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write index\n");
goto failure;
}
rv = 0;
failure:
if (fpSrc) {
fclose(fpSrc);
}
if (fpDest) {
fclose(fpDest);
}
if (rv) {
remove(dest);
}
if (indexBuf) {
free(indexBuf);
}
if (rv) {
remove(dest);
}
return rv;
}
/**
* Extracts a signature from a MAR file, base64 encodes it, and writes it out
*
* @param src The path of the source MAR file
* @param sigIndex The index of the signature to extract
* @param dest The path of file to write the signature to
* @return 0 on success
* -1 on error
*/
int extract_signature(const char* src, uint32_t sigIndex, const char* dest) {
FILE *fpSrc = NULL, *fpDest = NULL;
uint32_t i;
uint32_t signatureCount;
uint32_t signatureLen;
uint8_t* extractedSignature = NULL;
char* base64Encoded = NULL;
int rv = -1;
if (!src || !dest) {
fprintf(stderr, "ERROR: Invalid parameter passed in.\n");
goto failure;
}
fpSrc = fopen(src, "rb");
if (!fpSrc) {
fprintf(stderr, "ERROR: could not open source file: %s\n", src);
goto failure;
}
fpDest = fopen(dest, "wb");
if (!fpDest) {
fprintf(stderr, "ERROR: could not create target file: %s\n", dest);
goto failure;
}
/* Skip to the start of the signature block */
if (fseeko(fpSrc, SIGNATURE_BLOCK_OFFSET, SEEK_SET)) {
fprintf(stderr, "ERROR: could not seek to signature block\n");
goto failure;
}
/* Get the number of signatures */
if (fread(&signatureCount, sizeof(signatureCount), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: could not read signature count\n");
goto failure;
}
signatureCount = ntohl(signatureCount);
if (sigIndex >= signatureCount) {
fprintf(stderr, "ERROR: Signature index was out of range\n");
goto failure;
}
/* Skip to the correct signature */
for (i = 0; i <= sigIndex; i++) {
/* Avoid leaking while skipping signatures */
free(extractedSignature);
extractedSignature = NULL;
/* skip past the signature algorithm ID */
if (fseeko(fpSrc, sizeof(uint32_t), SEEK_CUR)) {
fprintf(stderr, "ERROR: Could not seek past sig algorithm ID.\n");
goto failure;
}
/* Get the signature length */
if (fread(&signatureLen, sizeof(signatureLen), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: could not read signature length\n");
goto failure;
}
signatureLen = ntohl(signatureLen);
/* Get the signature */
extractedSignature = malloc(signatureLen);
if (fread(extractedSignature, signatureLen, 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: could not read signature\n");
goto failure;
}
}
base64Encoded = BTOA_DataToAscii(extractedSignature, signatureLen);
if (!base64Encoded) {
fprintf(stderr, "ERROR: could not obtain base64 encoded data\n");
goto failure;
}
if (fwrite(base64Encoded, strlen(base64Encoded), 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write base64 encoded string\n");
goto failure;
}
rv = 0;
failure:
if (base64Encoded) {
PORT_Free(base64Encoded);
}
if (extractedSignature) {
free(extractedSignature);
}
if (fpSrc) {
fclose(fpSrc);
}
if (fpDest) {
fclose(fpDest);
}
if (rv) {
remove(dest);
}
return rv;
}
/**
* Imports a base64 encoded signature into a MAR file
*
* @param src The path of the source MAR file
* @param sigIndex The index of the signature to import
* @param base64SigFile A file which contains the signature to import
* @param dest The path of the destination MAR file with replaced
* signature
* @return 0 on success
* -1 on error
*/
int import_signature(const char* src, uint32_t sigIndex,
const char* base64SigFile, const char* dest) {
int rv = -1;
FILE* fpSrc = NULL;
FILE* fpDest = NULL;
FILE* fpSigFile = NULL;
uint32_t i;
uint32_t signatureCount, signatureLen, signatureAlgorithmID, numChunks,
leftOver;
char buf[BLOCKSIZE];
uint64_t sizeOfSrcMAR, sizeOfBase64EncodedFile;
char* passedInSignatureB64 = NULL;
uint8_t* passedInSignatureRaw = NULL;
uint8_t* extractedMARSignature = NULL;
unsigned int passedInSignatureLenRaw;
if (!src || !dest) {
fprintf(stderr, "ERROR: Invalid parameter passed in.\n");
goto failure;
}
fpSrc = fopen(src, "rb");
if (!fpSrc) {
fprintf(stderr, "ERROR: could not open source file: %s\n", src);
goto failure;
}
fpDest = fopen(dest, "wb");
if (!fpDest) {
fprintf(stderr, "ERROR: could not open dest file: %s\n", dest);
goto failure;
}
fpSigFile = fopen(base64SigFile, "rb");
if (!fpSigFile) {
fprintf(stderr, "ERROR: could not open sig file: %s\n", base64SigFile);
goto failure;
}
/* Get the src file size */
if (fseeko(fpSrc, 0, SEEK_END)) {
fprintf(stderr, "ERROR: Could not seek to end of src file.\n");
goto failure;
}
sizeOfSrcMAR = ftello(fpSrc);
if (fseeko(fpSrc, 0, SEEK_SET)) {
fprintf(stderr, "ERROR: Could not seek to start of src file.\n");
goto failure;
}
/* Get the sig file size */
if (fseeko(fpSigFile, 0, SEEK_END)) {
fprintf(stderr, "ERROR: Could not seek to end of sig file.\n");
goto failure;
}
sizeOfBase64EncodedFile = ftello(fpSigFile);
if (fseeko(fpSigFile, 0, SEEK_SET)) {
fprintf(stderr, "ERROR: Could not seek to start of sig file.\n");
goto failure;
}
/* Read in the base64 encoded signature to import */
passedInSignatureB64 = malloc(sizeOfBase64EncodedFile + 1);
passedInSignatureB64[sizeOfBase64EncodedFile] = '\0';
if (fread(passedInSignatureB64, sizeOfBase64EncodedFile, 1, fpSigFile) != 1) {
fprintf(stderr, "ERROR: Could read b64 sig file.\n");
goto failure;
}
/* Decode the base64 encoded data */
passedInSignatureRaw =
ATOB_AsciiToData(passedInSignatureB64, &passedInSignatureLenRaw);
if (!passedInSignatureRaw) {
fprintf(stderr, "ERROR: could not obtain base64 decoded data\n");
goto failure;
}
/* Read everything up until the signature block offset and write it out */
if (ReadAndWrite(fpSrc, fpDest, buf, SIGNATURE_BLOCK_OFFSET,
"signature block offset")) {
goto failure;
}
/* Get the number of signatures */
if (ReadAndWrite(fpSrc, fpDest, &signatureCount, sizeof(signatureCount),
"signature count")) {
goto failure;
}
signatureCount = ntohl(signatureCount);
if (signatureCount > MAX_SIGNATURES) {
fprintf(stderr, "ERROR: Signature count was out of range\n");
goto failure;
}
if (sigIndex >= signatureCount) {
fprintf(stderr, "ERROR: Signature index was out of range\n");
goto failure;
}
/* Read and write the whole signature block, but if we reach the
signature offset, then we should replace it with the specified
base64 decoded signature */
for (i = 0; i < signatureCount; i++) {
/* Read/Write the signature algorithm ID */
if (ReadAndWrite(fpSrc, fpDest, &signatureAlgorithmID,
sizeof(signatureAlgorithmID), "sig algorithm ID")) {
goto failure;
}
/* Read/Write the signature length */
if (ReadAndWrite(fpSrc, fpDest, &signatureLen, sizeof(signatureLen),
"sig length")) {
goto failure;
}
signatureLen = ntohl(signatureLen);
/* Get the signature */
if (extractedMARSignature) {
free(extractedMARSignature);
}
extractedMARSignature = malloc(signatureLen);
if (sigIndex == i) {
if (passedInSignatureLenRaw != signatureLen) {
fprintf(stderr, "ERROR: Signature length must be the same\n");
goto failure;
}
if (fread(extractedMARSignature, signatureLen, 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could not read signature\n");
goto failure;
}
if (fwrite(passedInSignatureRaw, passedInSignatureLenRaw, 1, fpDest) !=
1) {
fprintf(stderr, "ERROR: Could not write signature\n");
goto failure;
}
} else {
if (ReadAndWrite(fpSrc, fpDest, extractedMARSignature, signatureLen,
"signature")) {
goto failure;
}
}
}
/* We replaced the signature so let's just skip past the rest o the
file. */
numChunks = (sizeOfSrcMAR - ftello(fpSrc)) / BLOCKSIZE;
leftOver = (sizeOfSrcMAR - ftello(fpSrc)) % BLOCKSIZE;
/* Read each file and write it to the MAR file */
for (i = 0; i < numChunks; ++i) {
if (ReadAndWrite(fpSrc, fpDest, buf, BLOCKSIZE, "content block")) {
goto failure;
}
}
if (ReadAndWrite(fpSrc, fpDest, buf, leftOver, "left over content block")) {
goto failure;
}
rv = 0;
failure:
if (fpSrc) {
fclose(fpSrc);
}
if (fpDest) {
fclose(fpDest);
}
if (fpSigFile) {
fclose(fpSigFile);
}
if (rv) {
remove(dest);
}
if (extractedMARSignature) {
free(extractedMARSignature);
}
if (passedInSignatureB64) {
free(passedInSignatureB64);
}
if (passedInSignatureRaw) {
PORT_Free(passedInSignatureRaw);
}
return rv;
}
/**
* Writes out a copy of the MAR at src but with embedded signatures.
* The passed in MAR file must not already be signed or an error will
* be returned.
*
* @param NSSConfigDir The NSS directory containing the private key for
* signing
* @param certNames The nicknames of the certificate to use for signing
* @param certCount The number of certificate names contained in certNames.
* One signature will be produced for each certificate.
* @param src The path of the source MAR file to sign
* @param dest The path of the MAR file to write out that is signed
* @return 0 on success
* -1 on error
*/
int mar_repackage_and_sign(const char* NSSConfigDir,
const char* const* certNames, uint32_t certCount,
const char* src, const char* dest) {
uint32_t offsetToIndex, dstOffsetToIndex, indexLength, leftOver,
signatureAlgorithmID, numSignatures = 0, signatureSectionLength = 0;
uint32_t signatureLengths[MAX_SIGNATURES];
int64_t oldPos, numChunks, i, realSizeOfSrcMAR, signaturePlaceholderOffset,
numBytesToCopy, sizeOfEntireMAR = 0;
FILE *fpSrc = NULL, *fpDest = NULL;
int rv = -1, hasSignatureBlock;
SGNContext* ctxs[MAX_SIGNATURES];
SECItem secItems[MAX_SIGNATURES];
char buf[BLOCKSIZE];
SECKEYPrivateKey* privKeys[MAX_SIGNATURES];
CERTCertificate* certs[MAX_SIGNATURES];
char* indexBuf = NULL;
uint32_t k;
memset(signatureLengths, 0, sizeof(signatureLengths));
memset(ctxs, 0, sizeof(ctxs));
memset(secItems, 0, sizeof(secItems));
memset(privKeys, 0, sizeof(privKeys));
memset(certs, 0, sizeof(certs));
if (!NSSConfigDir || !certNames || certCount == 0 || !src || !dest) {
fprintf(stderr, "ERROR: Invalid parameter passed in.\n");
return -1;
}
if (NSSInitCryptoContext(NSSConfigDir)) {
fprintf(stderr, "ERROR: Could not init config dir: %s\n", NSSConfigDir);
goto failure;
}
PK11_SetPasswordFunc(SECU_GetModulePassword);
fpSrc = fopen(src, "rb");
if (!fpSrc) {
fprintf(stderr, "ERROR: could not open source file: %s\n", src);
goto failure;
}
fpDest = fopen(dest, "wb");
if (!fpDest) {
fprintf(stderr, "ERROR: could not create target file: %s\n", dest);
goto failure;
}
/* Determine if the source MAR file has the new fields for signing or not */
if (get_mar_file_info(src, &hasSignatureBlock, NULL, NULL, NULL, NULL)) {
fprintf(stderr, "ERROR: could not determine if MAR is old or new.\n");
goto failure;
}
for (k = 0; k < certCount; k++) {
if (NSSSignBegin(certNames[k], &ctxs[k], &privKeys[k], &certs[k],
&signatureLengths[k])) {
fprintf(stderr, "ERROR: NSSSignBegin failed\n");
goto failure;
}
}
/* MAR ID */
if (ReadWriteAndUpdateSignatures(fpSrc, fpDest, buf, MAR_ID_SIZE, ctxs,
certCount, "MAR ID")) {
goto failure;
}
/* Offset to index */
if (fread(&offsetToIndex, sizeof(offsetToIndex), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could not read offset\n");
goto failure;
}
offsetToIndex = ntohl(offsetToIndex);
/* Get the real size of the MAR */
oldPos = ftello(fpSrc);
if (fseeko(fpSrc, 0, SEEK_END)) {
fprintf(stderr, "ERROR: Could not seek to end of file.\n");
goto failure;
}
realSizeOfSrcMAR = ftello(fpSrc);
if (fseeko(fpSrc, oldPos, SEEK_SET)) {
fprintf(stderr, "ERROR: Could not seek back to current location.\n");
goto failure;
}
if (hasSignatureBlock) {
/* Get the MAR length and adjust its size */
if (fread(&sizeOfEntireMAR, sizeof(sizeOfEntireMAR), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could read mar size\n");
goto failure;
}
sizeOfEntireMAR = NETWORK_TO_HOST64(sizeOfEntireMAR);
if (sizeOfEntireMAR != realSizeOfSrcMAR) {
fprintf(stderr, "ERROR: Source MAR is not of the right size\n");
goto failure;
}
/* Get the num signatures in the source file */
if (fread(&numSignatures, sizeof(numSignatures), 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could read num signatures\n");
goto failure;
}
numSignatures = ntohl(numSignatures);
/* We do not support resigning, if you have multiple signatures,
you must add them all at the same time. */
if (numSignatures) {
fprintf(stderr, "ERROR: MAR is already signed\n");
goto failure;
}
} else {
sizeOfEntireMAR = realSizeOfSrcMAR;
}
if (((int64_t)offsetToIndex) > sizeOfEntireMAR) {
fprintf(stderr, "ERROR: Offset to index is larger than the file size.\n");
goto failure;
}
/* Calculate the total signature block length */
for (k = 0; k < certCount; k++) {
signatureSectionLength += sizeof(signatureAlgorithmID) +
sizeof(signatureLengths[k]) + signatureLengths[k];
}
dstOffsetToIndex = offsetToIndex;
if (!hasSignatureBlock) {
dstOffsetToIndex += sizeof(sizeOfEntireMAR) + sizeof(numSignatures);
}
dstOffsetToIndex += signatureSectionLength;
/* Write out the index offset */
dstOffsetToIndex = htonl(dstOffsetToIndex);
if (WriteAndUpdateSignatures(fpDest, &dstOffsetToIndex,
sizeof(dstOffsetToIndex), ctxs, certCount,
"index offset")) {
goto failure;
}
dstOffsetToIndex = ntohl(dstOffsetToIndex);
/* Write out the new MAR file size */
sizeOfEntireMAR += signatureSectionLength;
if (!hasSignatureBlock) {
sizeOfEntireMAR += sizeof(sizeOfEntireMAR) + sizeof(numSignatures);
}
/* Write out the MAR size */
sizeOfEntireMAR = HOST_TO_NETWORK64(sizeOfEntireMAR);
if (WriteAndUpdateSignatures(fpDest, &sizeOfEntireMAR,
sizeof(sizeOfEntireMAR), ctxs, certCount,
"size of MAR")) {
goto failure;
}
sizeOfEntireMAR = NETWORK_TO_HOST64(sizeOfEntireMAR);
/* Write out the number of signatures */
numSignatures = certCount;
numSignatures = htonl(numSignatures);
if (WriteAndUpdateSignatures(fpDest, &numSignatures, sizeof(numSignatures),
ctxs, certCount, "num signatures")) {
goto failure;
}
numSignatures = ntohl(numSignatures);
signaturePlaceholderOffset = ftello(fpDest);
for (k = 0; k < certCount; k++) {
/* Write out the signature algorithm ID, Only an ID of 2 is supported */
signatureAlgorithmID = htonl(2);
if (WriteAndUpdateSignatures(fpDest, &signatureAlgorithmID,
sizeof(signatureAlgorithmID), ctxs, certCount,
"num signatures")) {
goto failure;
}
signatureAlgorithmID = ntohl(signatureAlgorithmID);
/* Write out the signature length */
signatureLengths[k] = htonl(signatureLengths[k]);
if (WriteAndUpdateSignatures(fpDest, &signatureLengths[k],
sizeof(signatureLengths[k]), ctxs, certCount,
"signature length")) {
goto failure;
}
signatureLengths[k] = ntohl(signatureLengths[k]);
/* Write out a placeholder for the signature, we'll come back to this later
*** THIS IS NOT SIGNED because it is a placeholder that will be replaced
below, plus it is going to be the signature itself. *** */
memset(buf, 0, sizeof(buf));
if (fwrite(buf, signatureLengths[k], 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write signature length\n");
goto failure;
}
}
/* Write out the rest of the MAR excluding the index header and index
offsetToIndex unfortunately has to remain 32-bit because for backwards
compatibility with the old MAR file format. */
if (ftello(fpSrc) > ((int64_t)offsetToIndex)) {
fprintf(stderr, "ERROR: Index offset is too small.\n");
goto failure;
}
numBytesToCopy = ((int64_t)offsetToIndex) - ftello(fpSrc);
numChunks = numBytesToCopy / BLOCKSIZE;
leftOver = numBytesToCopy % BLOCKSIZE;
/* Read each file and write it to the MAR file */
for (i = 0; i < numChunks; ++i) {
if (ReadWriteAndUpdateSignatures(fpSrc, fpDest, buf, BLOCKSIZE, ctxs,
certCount, "content block")) {
goto failure;
}
}
/* Write out the left over */
if (ReadWriteAndUpdateSignatures(fpSrc, fpDest, buf, leftOver, ctxs,
certCount, "left over content block")) {
goto failure;
}
/* Length of the index */
if (ReadWriteAndUpdateSignatures(fpSrc, fpDest, &indexLength,
sizeof(indexLength), ctxs, certCount,
"index length")) {
goto failure;
}
indexLength = ntohl(indexLength);
/* Consume the index and adjust each index by signatureSectionLength */
indexBuf = malloc(indexLength);
if (fread(indexBuf, indexLength, 1, fpSrc) != 1) {
fprintf(stderr, "ERROR: Could not read index\n");
goto failure;
}
/* Adjust each entry in the index */
if (hasSignatureBlock) {
AdjustIndexContentOffsets(indexBuf, indexLength, signatureSectionLength);
} else {
AdjustIndexContentOffsets(indexBuf, indexLength,
sizeof(sizeOfEntireMAR) + sizeof(numSignatures) +
signatureSectionLength);
}
if (WriteAndUpdateSignatures(fpDest, indexBuf, indexLength, ctxs, certCount,
"index")) {
goto failure;
}
/* Ensure that we don't sign a file that is too large to be accepted by
the verification function. */
if (ftello(fpDest) > MAX_SIZE_OF_MAR_FILE) {
goto failure;
}
for (k = 0; k < certCount; k++) {
/* Get the signature */
if (SGN_End(ctxs[k], &secItems[k]) != SECSuccess) {
fprintf(stderr, "ERROR: Could not end signature context\n");
goto failure;
}
if (signatureLengths[k] != secItems[k].len) {
fprintf(stderr, "ERROR: Signature is not the expected length\n");
goto failure;
}
}
/* Get back to the location of the signature placeholder */
if (fseeko(fpDest, signaturePlaceholderOffset, SEEK_SET)) {
fprintf(stderr, "ERROR: Could not seek to signature offset\n");
goto failure;
}
for (k = 0; k < certCount; k++) {
/* Skip to the position of the next signature */
if (fseeko(fpDest,
sizeof(signatureAlgorithmID) + sizeof(signatureLengths[k]),
SEEK_CUR)) {
fprintf(stderr, "ERROR: Could not seek to signature offset\n");
goto failure;
}
/* Write out the calculated signature.
*** THIS IS NOT SIGNED because it is the signature itself. *** */
if (fwrite(secItems[k].data, secItems[k].len, 1, fpDest) != 1) {
fprintf(stderr, "ERROR: Could not write signature\n");
goto failure;
}
}
rv = 0;
failure:
if (fpSrc) {
fclose(fpSrc);
}
if (fpDest) {
fclose(fpDest);
}
if (rv) {
remove(dest);
}
if (indexBuf) {
free(indexBuf);
}
/* Cleanup */
for (k = 0; k < certCount; k++) {
if (ctxs[k]) {
SGN_DestroyContext(ctxs[k], PR_TRUE);
}
if (certs[k]) {
CERT_DestroyCertificate(certs[k]);
}
if (privKeys[k]) {
SECKEY_DestroyPrivateKey(privKeys[k]);
}
SECITEM_FreeItem(&secItems[k], PR_FALSE);
}
(void)NSS_Shutdown();
if (rv) {
remove(dest);
}
return rv;
}