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-rw-r--r--security/apps/AppSignatureVerification.cpp1560
1 files changed, 1560 insertions, 0 deletions
diff --git a/security/apps/AppSignatureVerification.cpp b/security/apps/AppSignatureVerification.cpp
new file mode 100644
index 000000000..8d64bfcb9
--- /dev/null
+++ b/security/apps/AppSignatureVerification.cpp
@@ -0,0 +1,1560 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#include "nsNSSCertificateDB.h"
+
+#include "AppTrustDomain.h"
+#include "CryptoTask.h"
+#include "NSSCertDBTrustDomain.h"
+#include "ScopedNSSTypes.h"
+#include "base64.h"
+#include "certdb.h"
+#include "mozilla/Casting.h"
+#include "mozilla/Logging.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/UniquePtr.h"
+#include "nsCOMPtr.h"
+#include "nsComponentManagerUtils.h"
+#include "nsDataSignatureVerifier.h"
+#include "nsHashKeys.h"
+#include "nsIDirectoryEnumerator.h"
+#include "nsIFile.h"
+#include "nsIFileStreams.h"
+#include "nsIInputStream.h"
+#include "nsIStringEnumerator.h"
+#include "nsIZipReader.h"
+#include "nsNSSCertificate.h"
+#include "nsNetUtil.h"
+#include "nsProxyRelease.h"
+#include "nsString.h"
+#include "nsTHashtable.h"
+#include "nssb64.h"
+#include "pkix/pkix.h"
+#include "pkix/pkixnss.h"
+#include "plstr.h"
+#include "secmime.h"
+
+
+using namespace mozilla::pkix;
+using namespace mozilla;
+using namespace mozilla::psm;
+
+extern mozilla::LazyLogModule gPIPNSSLog;
+
+namespace {
+
+// Reads a maximum of 1MB from a stream into the supplied buffer.
+// The reason for the 1MB limit is because this function is used to read
+// signature-related files and we want to avoid OOM. The uncompressed length of
+// an entry can be hundreds of times larger than the compressed version,
+// especially if someone has specifically crafted the entry to cause OOM or to
+// consume massive amounts of disk space.
+//
+// @param stream The input stream to read from.
+// @param buf The buffer that we read the stream into, which must have
+// already been allocated.
+nsresult
+ReadStream(const nsCOMPtr<nsIInputStream>& stream, /*out*/ SECItem& buf)
+{
+ // The size returned by Available() might be inaccurate so we need
+ // to check that Available() matches up with the actual length of
+ // the file.
+ uint64_t length;
+ nsresult rv = stream->Available(&length);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ // Cap the maximum accepted size of signature-related files at 1MB (which is
+ // still crazily huge) to avoid OOM. The uncompressed length of an entry can be
+ // hundreds of times larger than the compressed version, especially if
+ // someone has speifically crafted the entry to cause OOM or to consume
+ // massive amounts of disk space.
+ static const uint32_t MAX_LENGTH = 1024 * 1024;
+ if (length > MAX_LENGTH) {
+ return NS_ERROR_FILE_TOO_BIG;
+ }
+
+ // With bug 164695 in mind we +1 to leave room for null-terminating
+ // the buffer.
+ SECITEM_AllocItem(buf, static_cast<uint32_t>(length + 1));
+
+ // buf.len == length + 1. We attempt to read length + 1 bytes
+ // instead of length, so that we can check whether the metadata for
+ // the entry is incorrect.
+ uint32_t bytesRead;
+ rv = stream->Read(BitwiseCast<char*, unsigned char*>(buf.data), buf.len,
+ &bytesRead);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+ if (bytesRead != length) {
+ return NS_ERROR_FILE_CORRUPTED;
+ }
+
+ buf.data[buf.len - 1] = 0; // null-terminate
+
+ return NS_OK;
+}
+
+// Finds exactly one (signature metadata) JAR entry that matches the given
+// search pattern, and then load it. Fails if there are no matches or if
+// there is more than one match. If bugDigest is not null then on success
+// bufDigest will contain the SHA-1 digeset of the entry.
+nsresult
+FindAndLoadOneEntry(nsIZipReader * zip,
+ const nsACString & searchPattern,
+ /*out*/ nsACString & filename,
+ /*out*/ SECItem & buf,
+ /*optional, out*/ Digest * bufDigest)
+{
+ nsCOMPtr<nsIUTF8StringEnumerator> files;
+ nsresult rv = zip->FindEntries(searchPattern, getter_AddRefs(files));
+ if (NS_FAILED(rv) || !files) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ bool more;
+ rv = files->HasMore(&more);
+ NS_ENSURE_SUCCESS(rv, rv);
+ if (!more) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ rv = files->GetNext(filename);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Check if there is more than one match, if so then error!
+ rv = files->HasMore(&more);
+ NS_ENSURE_SUCCESS(rv, rv);
+ if (more) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ nsCOMPtr<nsIInputStream> stream;
+ rv = zip->GetInputStream(filename, getter_AddRefs(stream));
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ rv = ReadStream(stream, buf);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_INVALID;
+ }
+
+ if (bufDigest) {
+ rv = bufDigest->DigestBuf(SEC_OID_SHA1, buf.data, buf.len - 1);
+ NS_ENSURE_SUCCESS(rv, rv);
+ }
+
+ return NS_OK;
+}
+
+// Verify the digest of an entry. We avoid loading the entire entry into memory
+// at once, which would require memory in proportion to the size of the largest
+// entry. Instead, we require only a small, fixed amount of memory.
+//
+// @param stream an input stream from a JAR entry or file depending on whether
+// it is from a signed archive or unpacked into a directory
+// @param digestFromManifest The digest that we're supposed to check the file's
+// contents against, from the manifest
+// @param buf A scratch buffer that we use for doing the I/O, which must have
+// already been allocated. The size of this buffer is the unit
+// size of our I/O.
+nsresult
+VerifyStreamContentDigest(nsIInputStream* stream,
+ const SECItem& digestFromManifest, SECItem& buf)
+{
+ MOZ_ASSERT(buf.len > 0);
+ if (digestFromManifest.len != SHA1_LENGTH)
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+
+ nsresult rv;
+ uint64_t len64;
+ rv = stream->Available(&len64);
+ NS_ENSURE_SUCCESS(rv, rv);
+ if (len64 > UINT32_MAX) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_TOO_LARGE;
+ }
+
+ UniquePK11Context digestContext(PK11_CreateDigestContext(SEC_OID_SHA1));
+ if (!digestContext) {
+ return mozilla::psm::GetXPCOMFromNSSError(PR_GetError());
+ }
+
+ rv = MapSECStatus(PK11_DigestBegin(digestContext.get()));
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ uint64_t totalBytesRead = 0;
+ for (;;) {
+ uint32_t bytesRead;
+ rv = stream->Read(BitwiseCast<char*, unsigned char*>(buf.data), buf.len,
+ &bytesRead);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ if (bytesRead == 0) {
+ break; // EOF
+ }
+
+ totalBytesRead += bytesRead;
+ if (totalBytesRead >= UINT32_MAX) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_TOO_LARGE;
+ }
+
+ rv = MapSECStatus(PK11_DigestOp(digestContext.get(), buf.data, bytesRead));
+ NS_ENSURE_SUCCESS(rv, rv);
+ }
+
+ if (totalBytesRead != len64) {
+ // The metadata we used for Available() doesn't match the actual size of
+ // the entry.
+ return NS_ERROR_SIGNED_JAR_ENTRY_INVALID;
+ }
+
+ // Verify that the digests match.
+ Digest digest;
+ rv = digest.End(SEC_OID_SHA1, digestContext);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ if (SECITEM_CompareItem(&digestFromManifest, &digest.get()) != SECEqual) {
+ return NS_ERROR_SIGNED_JAR_MODIFIED_ENTRY;
+ }
+
+ return NS_OK;
+}
+
+nsresult
+VerifyEntryContentDigest(nsIZipReader* zip, const nsACString& aFilename,
+ const SECItem& digestFromManifest, SECItem& buf)
+{
+ nsCOMPtr<nsIInputStream> stream;
+ nsresult rv = zip->GetInputStream(aFilename, getter_AddRefs(stream));
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_MISSING;
+ }
+
+ return VerifyStreamContentDigest(stream, digestFromManifest, buf);
+}
+
+// @oaram aDir directory containing the unpacked signed archive
+// @param aFilename path of the target file relative to aDir
+// @param digestFromManifest The digest that we're supposed to check the file's
+// contents against, from the manifest
+// @param buf A scratch buffer that we use for doing the I/O
+nsresult
+VerifyFileContentDigest(nsIFile* aDir, const nsAString& aFilename,
+ const SECItem& digestFromManifest, SECItem& buf)
+{
+ // Find the file corresponding to the manifest path
+ nsCOMPtr<nsIFile> file;
+ nsresult rv = aDir->Clone(getter_AddRefs(file));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // We don't know how to handle JARs with signed directory entries.
+ // It's technically possible in the manifest but makes no sense on disk.
+ // Inside an archive we just ignore them, but here we have to treat it
+ // as an error because the signed bytes never got unpacked.
+ int32_t pos = 0;
+ int32_t slash;
+ int32_t namelen = aFilename.Length();
+ if (namelen == 0 || aFilename[namelen - 1] == '/') {
+ return NS_ERROR_SIGNED_JAR_ENTRY_INVALID;
+ }
+
+ // Append path segments one by one
+ do {
+ slash = aFilename.FindChar('/', pos);
+ int32_t segend = (slash == kNotFound) ? namelen : slash;
+ rv = file->Append(Substring(aFilename, pos, (segend - pos)));
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_INVALID;
+ }
+ pos = slash + 1;
+ } while (pos < namelen && slash != kNotFound);
+
+ bool exists;
+ rv = file->Exists(&exists);
+ if (NS_FAILED(rv) || !exists) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_MISSING;
+ }
+
+ bool isDir;
+ rv = file->IsDirectory(&isDir);
+ if (NS_FAILED(rv) || isDir) {
+ // We only support signed files, not directory entries
+ return NS_ERROR_SIGNED_JAR_ENTRY_INVALID;
+ }
+
+ // Open an input stream for that file and verify it.
+ nsCOMPtr<nsIInputStream> stream;
+ rv = NS_NewLocalFileInputStream(getter_AddRefs(stream), file, -1, -1,
+ nsIFileInputStream::CLOSE_ON_EOF);
+ if (NS_FAILED(rv) || !stream) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_MISSING;
+ }
+
+ return VerifyStreamContentDigest(stream, digestFromManifest, buf);
+}
+
+// On input, nextLineStart is the start of the current line. On output,
+// nextLineStart is the start of the next line.
+nsresult
+ReadLine(/*in/out*/ const char* & nextLineStart, /*out*/ nsCString & line,
+ bool allowContinuations = true)
+{
+ line.Truncate();
+ size_t previousLength = 0;
+ size_t currentLength = 0;
+ for (;;) {
+ const char* eol = PL_strpbrk(nextLineStart, "\r\n");
+
+ if (!eol) { // Reached end of file before newline
+ eol = nextLineStart + strlen(nextLineStart);
+ }
+
+ previousLength = currentLength;
+ line.Append(nextLineStart, eol - nextLineStart);
+ currentLength = line.Length();
+
+ // The spec says "No line may be longer than 72 bytes (not characters)"
+ // in its UTF8-encoded form.
+ static const size_t lineLimit = 72;
+ if (currentLength - previousLength > lineLimit) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // The spec says: "Implementations should support 65535-byte
+ // (not character) header values..."
+ if (currentLength > 65535) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ if (*eol == '\r') {
+ ++eol;
+ }
+ if (*eol == '\n') {
+ ++eol;
+ }
+
+ nextLineStart = eol;
+
+ if (*eol != ' ') {
+ // not a continuation
+ return NS_OK;
+ }
+
+ // continuation
+ if (!allowContinuations) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ ++nextLineStart; // skip space and keep appending
+ }
+}
+
+// The header strings are defined in the JAR specification.
+#define JAR_MF_SEARCH_STRING "(M|/M)ETA-INF/(M|m)(ANIFEST|anifest).(MF|mf)$"
+#define JAR_SF_SEARCH_STRING "(M|/M)ETA-INF/*.(SF|sf)$"
+#define JAR_RSA_SEARCH_STRING "(M|/M)ETA-INF/*.(RSA|rsa)$"
+#define JAR_META_DIR "META-INF"
+#define JAR_MF_HEADER "Manifest-Version: 1.0"
+#define JAR_SF_HEADER "Signature-Version: 1.0"
+
+nsresult
+ParseAttribute(const nsAutoCString & curLine,
+ /*out*/ nsAutoCString & attrName,
+ /*out*/ nsAutoCString & attrValue)
+{
+ // Find the colon that separates the name from the value.
+ int32_t colonPos = curLine.FindChar(':');
+ if (colonPos == kNotFound) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // set attrName to the name, skipping spaces between the name and colon
+ int32_t nameEnd = colonPos;
+ for (;;) {
+ if (nameEnd == 0) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID; // colon with no name
+ }
+ if (curLine[nameEnd - 1] != ' ')
+ break;
+ --nameEnd;
+ }
+ curLine.Left(attrName, nameEnd);
+
+ // Set attrValue to the value, skipping spaces between the colon and the
+ // value. The value may be empty.
+ int32_t valueStart = colonPos + 1;
+ int32_t curLineLength = curLine.Length();
+ while (valueStart != curLineLength && curLine[valueStart] == ' ') {
+ ++valueStart;
+ }
+ curLine.Right(attrValue, curLineLength - valueStart);
+
+ return NS_OK;
+}
+
+// Parses the version line of the MF or SF header.
+nsresult
+CheckManifestVersion(const char* & nextLineStart,
+ const nsACString & expectedHeader)
+{
+ // The JAR spec says: "Manifest-Version and Signature-Version must be first,
+ // and in exactly that case (so that they can be recognized easily as magic
+ // strings)."
+ nsAutoCString curLine;
+ nsresult rv = ReadLine(nextLineStart, curLine, false);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ if (!curLine.Equals(expectedHeader)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+ return NS_OK;
+}
+
+// Parses a signature file (SF) as defined in the JDK 8 JAR Specification.
+//
+// The SF file *must* contain exactly one SHA1-Digest-Manifest attribute in
+// the main section. All other sections are ignored. This means that this will
+// NOT parse old-style signature files that have separate digests per entry.
+// The JDK8 x-Digest-Manifest variant is better because:
+//
+// (1) It allows us to follow the principle that we should minimize the
+// processing of data that we do before we verify its signature. In
+// particular, with the x-Digest-Manifest style, we can verify the digest
+// of MANIFEST.MF before we parse it, which prevents malicious JARs
+// exploiting our MANIFEST.MF parser.
+// (2) It is more time-efficient and space-efficient to have one
+// x-Digest-Manifest instead of multiple x-Digest values.
+//
+// In order to get benefit (1), we do NOT implement the fallback to the older
+// mechanism as the spec requires/suggests. Also, for simplity's sake, we only
+// support exactly one SHA1-Digest-Manifest attribute, and no other
+// algorithms.
+//
+// filebuf must be null-terminated. On output, mfDigest will contain the
+// decoded value of SHA1-Digest-Manifest.
+nsresult
+ParseSF(const char* filebuf, /*out*/ SECItem & mfDigest)
+{
+ nsresult rv;
+
+ const char* nextLineStart = filebuf;
+ rv = CheckManifestVersion(nextLineStart, NS_LITERAL_CSTRING(JAR_SF_HEADER));
+ if (NS_FAILED(rv))
+ return rv;
+
+ // Find SHA1-Digest-Manifest
+ for (;;) {
+ nsAutoCString curLine;
+ rv = ReadLine(nextLineStart, curLine);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ if (curLine.Length() == 0) {
+ // End of main section (blank line or end-of-file), and no
+ // SHA1-Digest-Manifest found.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ nsAutoCString attrName;
+ nsAutoCString attrValue;
+ rv = ParseAttribute(curLine, attrName, attrValue);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ if (attrName.LowerCaseEqualsLiteral("sha1-digest-manifest")) {
+ rv = MapSECStatus(ATOB_ConvertAsciiToItem(&mfDigest, attrValue.get()));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // There could be multiple SHA1-Digest-Manifest attributes, which
+ // would be an error, but it's better to just skip any erroneous
+ // duplicate entries rather than trying to detect them, because:
+ //
+ // (1) It's simpler, and simpler generally means more secure
+ // (2) An attacker can't make us accept a JAR we would otherwise
+ // reject just by adding additional SHA1-Digest-Manifest
+ // attributes.
+ break;
+ }
+
+ // ignore unrecognized attributes
+ }
+
+ return NS_OK;
+}
+
+// Parses MANIFEST.MF. The filenames of all entries will be returned in
+// mfItems. buf must be a pre-allocated scratch buffer that is used for doing
+// I/O.
+nsresult
+ParseMF(const char* filebuf, nsIZipReader * zip,
+ /*out*/ nsTHashtable<nsCStringHashKey> & mfItems,
+ ScopedAutoSECItem & buf)
+{
+ nsresult rv;
+
+ const char* nextLineStart = filebuf;
+
+ rv = CheckManifestVersion(nextLineStart, NS_LITERAL_CSTRING(JAR_MF_HEADER));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Skip the rest of the header section, which ends with a blank line.
+ {
+ nsAutoCString line;
+ do {
+ rv = ReadLine(nextLineStart, line);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ } while (line.Length() > 0);
+
+ // Manifest containing no file entries is OK, though useless.
+ if (*nextLineStart == '\0') {
+ return NS_OK;
+ }
+ }
+
+ nsAutoCString curItemName;
+ ScopedAutoSECItem digest;
+
+ for (;;) {
+ nsAutoCString curLine;
+ rv = ReadLine(nextLineStart, curLine);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ if (curLine.Length() == 0) {
+ // end of section (blank line or end-of-file)
+
+ if (curItemName.Length() == 0) {
+ // '...Each section must start with an attribute with the name as
+ // "Name",...', so every section must have a Name attribute.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ if (digest.len == 0) {
+ // We require every entry to have a digest, since we require every
+ // entry to be signed and we don't allow duplicate entries.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ if (mfItems.Contains(curItemName)) {
+ // Duplicate entry
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // Verify that the entry's content digest matches the digest from this
+ // MF section.
+ rv = VerifyEntryContentDigest(zip, curItemName, digest, buf);
+ if (NS_FAILED(rv))
+ return rv;
+
+ mfItems.PutEntry(curItemName);
+
+ if (*nextLineStart == '\0') // end-of-file
+ break;
+
+ // reset so we know we haven't encountered either of these for the next
+ // item yet.
+ curItemName.Truncate();
+ digest.reset();
+
+ continue; // skip the rest of the loop below
+ }
+
+ nsAutoCString attrName;
+ nsAutoCString attrValue;
+ rv = ParseAttribute(curLine, attrName, attrValue);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Lines to look for:
+
+ // (1) Digest:
+ if (attrName.LowerCaseEqualsLiteral("sha1-digest"))
+ {
+ if (digest.len > 0) // multiple SHA1 digests in section
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+
+ rv = MapSECStatus(ATOB_ConvertAsciiToItem(&digest, attrValue.get()));
+ if (NS_FAILED(rv))
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+
+ continue;
+ }
+
+ // (2) Name: associates this manifest section with a file in the jar.
+ if (attrName.LowerCaseEqualsLiteral("name"))
+ {
+ if (MOZ_UNLIKELY(curItemName.Length() > 0)) // multiple names in section
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+
+ if (MOZ_UNLIKELY(attrValue.Length() == 0))
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+
+ curItemName = attrValue;
+
+ continue;
+ }
+
+ // (3) Magic: the only other must-understand attribute
+ if (attrName.LowerCaseEqualsLiteral("magic")) {
+ // We don't understand any magic, so we can't verify an entry that
+ // requires magic. Since we require every entry to have a valid
+ // signature, we have no choice but to reject the entry.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // unrecognized attributes must be ignored
+ }
+
+ return NS_OK;
+}
+
+struct VerifyCertificateContext {
+ AppTrustedRoot trustedRoot;
+ UniqueCERTCertList& builtChain;
+};
+
+nsresult
+VerifyCertificate(CERTCertificate* signerCert, void* voidContext, void* pinArg)
+{
+ // TODO: null pinArg is tolerated.
+ if (NS_WARN_IF(!signerCert) || NS_WARN_IF(!voidContext)) {
+ return NS_ERROR_INVALID_ARG;
+ }
+ const VerifyCertificateContext& context =
+ *static_cast<const VerifyCertificateContext*>(voidContext);
+
+ AppTrustDomain trustDomain(context.builtChain, pinArg);
+ if (trustDomain.SetTrustedRoot(context.trustedRoot) != SECSuccess) {
+ return MapSECStatus(SECFailure);
+ }
+ Input certDER;
+ mozilla::pkix::Result rv = certDER.Init(signerCert->derCert.data,
+ signerCert->derCert.len);
+ if (rv != Success) {
+ return mozilla::psm::GetXPCOMFromNSSError(MapResultToPRErrorCode(rv));
+ }
+
+ rv = BuildCertChain(trustDomain, certDER, Now(),
+ EndEntityOrCA::MustBeEndEntity,
+ KeyUsage::digitalSignature,
+ KeyPurposeId::id_kp_codeSigning,
+ CertPolicyId::anyPolicy,
+ nullptr/*stapledOCSPResponse*/);
+ if (rv == mozilla::pkix::Result::ERROR_EXPIRED_CERTIFICATE) {
+ // For code-signing you normally need trusted 3rd-party timestamps to
+ // handle expiration properly. The signer could always mess with their
+ // system clock so you can't trust the certificate was un-expired when
+ // the signing took place. The choice is either to ignore expiration
+ // or to enforce expiration at time of use. The latter leads to the
+ // user-hostile result that perfectly good code stops working.
+ //
+ // Our package format doesn't support timestamps (nor do we have a
+ // trusted 3rd party timestamper), but since we sign all of our apps and
+ // add-ons ourselves we can trust ourselves not to mess with the clock
+ // on the signing systems. We also have a revocation mechanism if we
+ // need it. It's OK to ignore cert expiration under these conditions.
+ //
+ // This is an invalid approach if
+ // * we issue certs to let others sign their own packages
+ // * mozilla::pkix returns "expired" when there are "worse" problems
+ // with the certificate or chain.
+ // (see bug 1267318)
+ rv = Success;
+ }
+ if (rv != Success) {
+ return mozilla::psm::GetXPCOMFromNSSError(MapResultToPRErrorCode(rv));
+ }
+
+ return NS_OK;
+}
+
+nsresult
+VerifySignature(AppTrustedRoot trustedRoot, const SECItem& buffer,
+ const SECItem& detachedDigest,
+ /*out*/ UniqueCERTCertList& builtChain)
+{
+ // Currently, this function is only called within the CalculateResult() method
+ // of CryptoTasks. As such, NSS should not be shut down at this point and the
+ // CryptoTask implementation should already hold a nsNSSShutDownPreventionLock.
+ // We acquire a nsNSSShutDownPreventionLock here solely to prove we did to
+ // VerifyCMSDetachedSignatureIncludingCertificate().
+ nsNSSShutDownPreventionLock locker;
+ VerifyCertificateContext context = { trustedRoot, builtChain };
+ // XXX: missing pinArg
+ return VerifyCMSDetachedSignatureIncludingCertificate(buffer, detachedDigest,
+ VerifyCertificate,
+ &context, nullptr,
+ locker);
+}
+
+NS_IMETHODIMP
+OpenSignedAppFile(AppTrustedRoot aTrustedRoot, nsIFile* aJarFile,
+ /*out, optional */ nsIZipReader** aZipReader,
+ /*out, optional */ nsIX509Cert** aSignerCert)
+{
+ NS_ENSURE_ARG_POINTER(aJarFile);
+
+ if (aZipReader) {
+ *aZipReader = nullptr;
+ }
+
+ if (aSignerCert) {
+ *aSignerCert = nullptr;
+ }
+
+ nsresult rv;
+
+ static NS_DEFINE_CID(kZipReaderCID, NS_ZIPREADER_CID);
+ nsCOMPtr<nsIZipReader> zip = do_CreateInstance(kZipReaderCID, &rv);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ rv = zip->Open(aJarFile);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Signature (RSA) file
+ nsAutoCString sigFilename;
+ ScopedAutoSECItem sigBuffer;
+ rv = FindAndLoadOneEntry(zip, nsLiteralCString(JAR_RSA_SEARCH_STRING),
+ sigFilename, sigBuffer, nullptr);
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_NOT_SIGNED;
+ }
+
+ // Signature (SF) file
+ nsAutoCString sfFilename;
+ ScopedAutoSECItem sfBuffer;
+ Digest sfCalculatedDigest;
+ rv = FindAndLoadOneEntry(zip, NS_LITERAL_CSTRING(JAR_SF_SEARCH_STRING),
+ sfFilename, sfBuffer, &sfCalculatedDigest);
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ sigBuffer.type = siBuffer;
+ UniqueCERTCertList builtChain;
+ rv = VerifySignature(aTrustedRoot, sigBuffer, sfCalculatedDigest.get(),
+ builtChain);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ ScopedAutoSECItem mfDigest;
+ rv = ParseSF(BitwiseCast<char*, unsigned char*>(sfBuffer.data), mfDigest);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Manifest (MF) file
+ nsAutoCString mfFilename;
+ ScopedAutoSECItem manifestBuffer;
+ Digest mfCalculatedDigest;
+ rv = FindAndLoadOneEntry(zip, NS_LITERAL_CSTRING(JAR_MF_SEARCH_STRING),
+ mfFilename, manifestBuffer, &mfCalculatedDigest);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ if (SECITEM_CompareItem(&mfDigest, &mfCalculatedDigest.get()) != SECEqual) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // Allocate the I/O buffer only once per JAR, instead of once per entry, in
+ // order to minimize malloc/free calls and in order to avoid fragmenting
+ // memory.
+ ScopedAutoSECItem buf(128 * 1024);
+
+ nsTHashtable<nsCStringHashKey> items;
+
+ rv = ParseMF(BitwiseCast<char*, unsigned char*>(manifestBuffer.data), zip,
+ items, buf);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Verify every entry in the file.
+ nsCOMPtr<nsIUTF8StringEnumerator> entries;
+ rv = zip->FindEntries(EmptyCString(), getter_AddRefs(entries));
+ if (NS_SUCCEEDED(rv) && !entries) {
+ rv = NS_ERROR_UNEXPECTED;
+ }
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ for (;;) {
+ bool hasMore;
+ rv = entries->HasMore(&hasMore);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ if (!hasMore) {
+ break;
+ }
+
+ nsAutoCString entryFilename;
+ rv = entries->GetNext(entryFilename);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ MOZ_LOG(gPIPNSSLog, LogLevel::Debug, ("Verifying digests for %s",
+ entryFilename.get()));
+
+ // The files that comprise the signature mechanism are not covered by the
+ // signature.
+ //
+ // XXX: This is OK for a single signature, but doesn't work for
+ // multiple signatures, because the metadata for the other signatures
+ // is not signed either.
+ if (entryFilename == mfFilename ||
+ entryFilename == sfFilename ||
+ entryFilename == sigFilename) {
+ continue;
+ }
+
+ if (entryFilename.Length() == 0) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_INVALID;
+ }
+
+ // Entries with names that end in "/" are directory entries, which are not
+ // signed.
+ //
+ // XXX: As long as we don't unpack the JAR into the filesystem, the "/"
+ // entries are harmless. But, it is not clear what the security
+ // implications of directory entries are if/when we were to unpackage the
+ // JAR into the filesystem.
+ if (entryFilename[entryFilename.Length() - 1] == '/') {
+ continue;
+ }
+
+ nsCStringHashKey * item = items.GetEntry(entryFilename);
+ if (!item) {
+ return NS_ERROR_SIGNED_JAR_UNSIGNED_ENTRY;
+ }
+
+ // Remove the item so we can check for leftover items later
+ items.RemoveEntry(item);
+ }
+
+ // We verified that every entry that we require to be signed is signed. But,
+ // were there any missing entries--that is, entries that are mentioned in the
+ // manifest but missing from the archive?
+ if (items.Count() != 0) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_MISSING;
+ }
+
+ // Return the reader to the caller if they want it
+ if (aZipReader) {
+ zip.forget(aZipReader);
+ }
+
+ // Return the signer's certificate to the reader if they want it.
+ // XXX: We should return an nsIX509CertList with the whole validated chain.
+ if (aSignerCert) {
+ CERTCertListNode* signerCertNode = CERT_LIST_HEAD(builtChain);
+ if (!signerCertNode || CERT_LIST_END(signerCertNode, builtChain) ||
+ !signerCertNode->cert) {
+ return NS_ERROR_FAILURE;
+ }
+ nsCOMPtr<nsIX509Cert> signerCert =
+ nsNSSCertificate::Create(signerCertNode->cert);
+ NS_ENSURE_TRUE(signerCert, NS_ERROR_OUT_OF_MEMORY);
+ signerCert.forget(aSignerCert);
+ }
+
+ return NS_OK;
+}
+
+nsresult
+VerifySignedManifest(AppTrustedRoot aTrustedRoot,
+ nsIInputStream* aManifestStream,
+ nsIInputStream* aSignatureStream,
+ /*out, optional */ nsIX509Cert** aSignerCert)
+{
+ NS_ENSURE_ARG(aManifestStream);
+ NS_ENSURE_ARG(aSignatureStream);
+
+ if (aSignerCert) {
+ *aSignerCert = nullptr;
+ }
+
+ // Load signature file in buffer
+ ScopedAutoSECItem signatureBuffer;
+ nsresult rv = ReadStream(aSignatureStream, signatureBuffer);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ signatureBuffer.type = siBuffer;
+
+ // Load manifest file in buffer
+ ScopedAutoSECItem manifestBuffer;
+ rv = ReadStream(aManifestStream, manifestBuffer);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Calculate SHA1 digest of the manifest buffer
+ Digest manifestCalculatedDigest;
+ rv = manifestCalculatedDigest.DigestBuf(SEC_OID_SHA1,
+ manifestBuffer.data,
+ manifestBuffer.len - 1); // buffer is null terminated
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ // Get base64 encoded string from manifest buffer digest
+ UniquePORTString
+ base64EncDigest(NSSBase64_EncodeItem(nullptr, nullptr, 0,
+ const_cast<SECItem*>(&manifestCalculatedDigest.get())));
+ if (NS_WARN_IF(!base64EncDigest)) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+
+ // Calculate SHA1 digest of the base64 encoded string
+ Digest doubleDigest;
+ rv = doubleDigest.DigestBuf(SEC_OID_SHA1,
+ BitwiseCast<uint8_t*, char*>(base64EncDigest.get()),
+ strlen(base64EncDigest.get()));
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ // Verify the manifest signature (signed digest of the base64 encoded string)
+ UniqueCERTCertList builtChain;
+ rv = VerifySignature(aTrustedRoot, signatureBuffer,
+ doubleDigest.get(), builtChain);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Return the signer's certificate to the reader if they want it.
+ if (aSignerCert) {
+ CERTCertListNode* signerCertNode = CERT_LIST_HEAD(builtChain);
+ if (!signerCertNode || CERT_LIST_END(signerCertNode, builtChain) ||
+ !signerCertNode->cert) {
+ return NS_ERROR_FAILURE;
+ }
+ nsCOMPtr<nsIX509Cert> signerCert =
+ nsNSSCertificate::Create(signerCertNode->cert);
+ if (NS_WARN_IF(!signerCert)) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+
+ signerCert.forget(aSignerCert);
+ }
+
+ return NS_OK;
+}
+
+class OpenSignedAppFileTask final : public CryptoTask
+{
+public:
+ OpenSignedAppFileTask(AppTrustedRoot aTrustedRoot, nsIFile* aJarFile,
+ nsIOpenSignedAppFileCallback* aCallback)
+ : mTrustedRoot(aTrustedRoot)
+ , mJarFile(aJarFile)
+ , mCallback(new nsMainThreadPtrHolder<nsIOpenSignedAppFileCallback>(aCallback))
+ {
+ }
+
+private:
+ virtual nsresult CalculateResult() override
+ {
+ return OpenSignedAppFile(mTrustedRoot, mJarFile,
+ getter_AddRefs(mZipReader),
+ getter_AddRefs(mSignerCert));
+ }
+
+ // nsNSSCertificate implements nsNSSShutdownObject, so there's nothing that
+ // needs to be released
+ virtual void ReleaseNSSResources() override { }
+
+ virtual void CallCallback(nsresult rv) override
+ {
+ (void) mCallback->OpenSignedAppFileFinished(rv, mZipReader, mSignerCert);
+ }
+
+ const AppTrustedRoot mTrustedRoot;
+ const nsCOMPtr<nsIFile> mJarFile;
+ nsMainThreadPtrHandle<nsIOpenSignedAppFileCallback> mCallback;
+ nsCOMPtr<nsIZipReader> mZipReader; // out
+ nsCOMPtr<nsIX509Cert> mSignerCert; // out
+};
+
+class VerifySignedmanifestTask final : public CryptoTask
+{
+public:
+ VerifySignedmanifestTask(AppTrustedRoot aTrustedRoot,
+ nsIInputStream* aManifestStream,
+ nsIInputStream* aSignatureStream,
+ nsIVerifySignedManifestCallback* aCallback)
+ : mTrustedRoot(aTrustedRoot)
+ , mManifestStream(aManifestStream)
+ , mSignatureStream(aSignatureStream)
+ , mCallback(
+ new nsMainThreadPtrHolder<nsIVerifySignedManifestCallback>(aCallback))
+ {
+ }
+
+private:
+ virtual nsresult CalculateResult() override
+ {
+ return VerifySignedManifest(mTrustedRoot, mManifestStream,
+ mSignatureStream, getter_AddRefs(mSignerCert));
+ }
+
+ // nsNSSCertificate implements nsNSSShutdownObject, so there's nothing that
+ // needs to be released
+ virtual void ReleaseNSSResources() override { }
+
+ virtual void CallCallback(nsresult rv) override
+ {
+ (void) mCallback->VerifySignedManifestFinished(rv, mSignerCert);
+ }
+
+ const AppTrustedRoot mTrustedRoot;
+ const nsCOMPtr<nsIInputStream> mManifestStream;
+ const nsCOMPtr<nsIInputStream> mSignatureStream;
+ nsMainThreadPtrHandle<nsIVerifySignedManifestCallback> mCallback;
+ nsCOMPtr<nsIX509Cert> mSignerCert; // out
+};
+
+} // unnamed namespace
+
+NS_IMETHODIMP
+nsNSSCertificateDB::OpenSignedAppFileAsync(
+ AppTrustedRoot aTrustedRoot, nsIFile* aJarFile,
+ nsIOpenSignedAppFileCallback* aCallback)
+{
+ NS_ENSURE_ARG_POINTER(aJarFile);
+ NS_ENSURE_ARG_POINTER(aCallback);
+ RefPtr<OpenSignedAppFileTask> task(new OpenSignedAppFileTask(aTrustedRoot,
+ aJarFile,
+ aCallback));
+ return task->Dispatch("SignedJAR");
+}
+
+NS_IMETHODIMP
+nsNSSCertificateDB::VerifySignedManifestAsync(
+ AppTrustedRoot aTrustedRoot, nsIInputStream* aManifestStream,
+ nsIInputStream* aSignatureStream, nsIVerifySignedManifestCallback* aCallback)
+{
+ NS_ENSURE_ARG_POINTER(aManifestStream);
+ NS_ENSURE_ARG_POINTER(aSignatureStream);
+ NS_ENSURE_ARG_POINTER(aCallback);
+
+ RefPtr<VerifySignedmanifestTask> task(
+ new VerifySignedmanifestTask(aTrustedRoot, aManifestStream,
+ aSignatureStream, aCallback));
+ return task->Dispatch("SignedManifest");
+}
+
+
+//
+// Signature verification for archives unpacked into a file structure
+//
+
+// Finds the "*.rsa" signature file in the META-INF directory and returns
+// the name. It is an error if there are none or more than one .rsa file
+nsresult
+FindSignatureFilename(nsIFile* aMetaDir,
+ /*out*/ nsAString& aFilename)
+{
+ nsCOMPtr<nsISimpleEnumerator> entries;
+ nsresult rv = aMetaDir->GetDirectoryEntries(getter_AddRefs(entries));
+ nsCOMPtr<nsIDirectoryEnumerator> files = do_QueryInterface(entries);
+ if (NS_FAILED(rv) || !files) {
+ return NS_ERROR_SIGNED_JAR_NOT_SIGNED;
+ }
+
+ bool found = false;
+ nsCOMPtr<nsIFile> file;
+ rv = files->GetNextFile(getter_AddRefs(file));
+
+ while (NS_SUCCEEDED(rv) && file) {
+ nsAutoString leafname;
+ rv = file->GetLeafName(leafname);
+ if (NS_SUCCEEDED(rv)) {
+ if (StringEndsWith(leafname, NS_LITERAL_STRING(".rsa"))) {
+ if (!found) {
+ found = true;
+ aFilename = leafname;
+ } else {
+ // second signature file is an error
+ rv = NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ break;
+ }
+ }
+ rv = files->GetNextFile(getter_AddRefs(file));
+ }
+ }
+
+ if (!found) {
+ rv = NS_ERROR_SIGNED_JAR_NOT_SIGNED;
+ }
+
+ files->Close();
+ return rv;
+}
+
+// Loads the signature metadata file that matches the given filename in
+// the passed-in Meta-inf directory. If bufDigest is not null then on
+// success bufDigest will contain the SHA-1 digest of the entry.
+nsresult
+LoadOneMetafile(nsIFile* aMetaDir,
+ const nsAString& aFilename,
+ /*out*/ SECItem& aBuf,
+ /*optional, out*/ Digest* aBufDigest)
+{
+ nsCOMPtr<nsIFile> metafile;
+ nsresult rv = aMetaDir->Clone(getter_AddRefs(metafile));
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ rv = metafile->Append(aFilename);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ bool exists;
+ rv = metafile->Exists(&exists);
+ if (NS_FAILED(rv) || !exists) {
+ // we can call a missing .rsa file "unsigned" but FindSignatureFilename()
+ // already found one: missing other metadata files means a broken signature.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ nsCOMPtr<nsIInputStream> stream;
+ rv = NS_NewLocalFileInputStream(getter_AddRefs(stream), metafile);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ rv = ReadStream(stream, aBuf);
+ stream->Close();
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ if (aBufDigest) {
+ rv = aBufDigest->DigestBuf(SEC_OID_SHA1, aBuf.data, aBuf.len - 1);
+ NS_ENSURE_SUCCESS(rv, rv);
+ }
+
+ return NS_OK;
+}
+
+// Parses MANIFEST.MF and verifies the contents of the unpacked files
+// listed in the manifest.
+// The filenames of all entries will be returned in aMfItems. aBuf must
+// be a pre-allocated scratch buffer that is used for doing I/O.
+nsresult
+ParseMFUnpacked(const char* aFilebuf, nsIFile* aDir,
+ /*out*/ nsTHashtable<nsStringHashKey>& aMfItems,
+ ScopedAutoSECItem& aBuf)
+{
+ nsresult rv;
+
+ const char* nextLineStart = aFilebuf;
+
+ rv = CheckManifestVersion(nextLineStart, NS_LITERAL_CSTRING(JAR_MF_HEADER));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Skip the rest of the header section, which ends with a blank line.
+ {
+ nsAutoCString line;
+ do {
+ rv = ReadLine(nextLineStart, line);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ } while (line.Length() > 0);
+
+ // Manifest containing no file entries is OK, though useless.
+ if (*nextLineStart == '\0') {
+ return NS_OK;
+ }
+ }
+
+ nsAutoString curItemName;
+ ScopedAutoSECItem digest;
+
+ for (;;) {
+ nsAutoCString curLine;
+ rv = ReadLine(nextLineStart, curLine);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ if (curLine.Length() == 0) {
+ // end of section (blank line or end-of-file)
+
+ if (curItemName.Length() == 0) {
+ // '...Each section must start with an attribute with the name as
+ // "Name",...', so every section must have a Name attribute.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ if (digest.len == 0) {
+ // We require every entry to have a digest, since we require every
+ // entry to be signed and we don't allow duplicate entries.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ if (aMfItems.Contains(curItemName)) {
+ // Duplicate entry
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // Verify that the file's content digest matches the digest from this
+ // MF section.
+ rv = VerifyFileContentDigest(aDir, curItemName, digest, aBuf);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ aMfItems.PutEntry(curItemName);
+
+ if (*nextLineStart == '\0') {
+ // end-of-file
+ break;
+ }
+
+ // reset so we know we haven't encountered either of these for the next
+ // item yet.
+ curItemName.Truncate();
+ digest.reset();
+
+ continue; // skip the rest of the loop below
+ }
+
+ nsAutoCString attrName;
+ nsAutoCString attrValue;
+ rv = ParseAttribute(curLine, attrName, attrValue);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Lines to look for:
+
+ // (1) Digest:
+ if (attrName.LowerCaseEqualsLiteral("sha1-digest")) {
+ if (digest.len > 0) {
+ // multiple SHA1 digests in section
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ rv = MapSECStatus(ATOB_ConvertAsciiToItem(&digest, attrValue.get()));
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ continue;
+ }
+
+ // (2) Name: associates this manifest section with a file in the jar.
+ if (attrName.LowerCaseEqualsLiteral("name")) {
+ if (MOZ_UNLIKELY(curItemName.Length() > 0)) {
+ // multiple names in section
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ if (MOZ_UNLIKELY(attrValue.Length() == 0)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ curItemName = NS_ConvertUTF8toUTF16(attrValue);
+
+ continue;
+ }
+
+ // (3) Magic: the only other must-understand attribute
+ if (attrName.LowerCaseEqualsLiteral("magic")) {
+ // We don't understand any magic, so we can't verify an entry that
+ // requires magic. Since we require every entry to have a valid
+ // signature, we have no choice but to reject the entry.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // unrecognized attributes must be ignored
+ }
+
+ return NS_OK;
+}
+
+// recursively check a directory tree for files not in the list of
+// verified files we found in the manifest. For each file we find
+// Check it against the files found in the manifest. If the file wasn't
+// in the manifest then it's unsigned and we can stop looking. Otherwise
+// remove it from the collection so we can check leftovers later.
+//
+// @param aDir Directory to check
+// @param aPath Relative path to that directory (to check against aItems)
+// @param aItems All the files found
+// @param *Filename signature files that won't be in the manifest
+nsresult
+CheckDirForUnsignedFiles(nsIFile* aDir,
+ const nsString& aPath,
+ /* in/out */ nsTHashtable<nsStringHashKey>& aItems,
+ const nsAString& sigFilename,
+ const nsAString& sfFilename,
+ const nsAString& mfFilename)
+{
+ nsCOMPtr<nsISimpleEnumerator> entries;
+ nsresult rv = aDir->GetDirectoryEntries(getter_AddRefs(entries));
+ nsCOMPtr<nsIDirectoryEnumerator> files = do_QueryInterface(entries);
+ if (NS_FAILED(rv) || !files) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_MISSING;
+ }
+
+ bool inMeta = StringBeginsWith(aPath, NS_LITERAL_STRING(JAR_META_DIR));
+
+ while (NS_SUCCEEDED(rv)) {
+ nsCOMPtr<nsIFile> file;
+ rv = files->GetNextFile(getter_AddRefs(file));
+ if (NS_FAILED(rv) || !file) {
+ break;
+ }
+
+ nsAutoString leafname;
+ rv = file->GetLeafName(leafname);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ nsAutoString curName(aPath + leafname);
+
+ bool isDir;
+ rv = file->IsDirectory(&isDir);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // if it's a directory we need to recurse
+ if (isDir) {
+ curName.Append(NS_LITERAL_STRING("/"));
+ rv = CheckDirForUnsignedFiles(file, curName, aItems,
+ sigFilename, sfFilename, mfFilename);
+ } else {
+ // The files that comprise the signature mechanism are not covered by the
+ // signature.
+ //
+ // XXX: This is OK for a single signature, but doesn't work for
+ // multiple signatures because the metadata for the other signatures
+ // is not signed either.
+ if (inMeta && ( leafname == sigFilename ||
+ leafname == sfFilename ||
+ leafname == mfFilename )) {
+ continue;
+ }
+
+ // make sure the current file was found in the manifest
+ nsStringHashKey* item = aItems.GetEntry(curName);
+ if (!item) {
+ return NS_ERROR_SIGNED_JAR_UNSIGNED_ENTRY;
+ }
+
+ // Remove the item so we can check for leftover items later
+ aItems.RemoveEntry(item);
+ }
+ }
+ files->Close();
+ return rv;
+}
+
+/*
+ * Verify the signature of a directory structure as if it were a
+ * signed JAR file (used for unpacked JARs)
+ */
+nsresult
+VerifySignedDirectory(AppTrustedRoot aTrustedRoot,
+ nsIFile* aDirectory,
+ /*out, optional */ nsIX509Cert** aSignerCert)
+{
+ NS_ENSURE_ARG_POINTER(aDirectory);
+
+ if (aSignerCert) {
+ *aSignerCert = nullptr;
+ }
+
+ // Make sure there's a META-INF directory
+
+ nsCOMPtr<nsIFile> metaDir;
+ nsresult rv = aDirectory->Clone(getter_AddRefs(metaDir));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ rv = metaDir->Append(NS_LITERAL_STRING(JAR_META_DIR));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ bool exists;
+ rv = metaDir->Exists(&exists);
+ if (NS_FAILED(rv) || !exists) {
+ return NS_ERROR_SIGNED_JAR_NOT_SIGNED;
+ }
+ bool isDirectory;
+ rv = metaDir->IsDirectory(&isDirectory);
+ if (NS_FAILED(rv) || !isDirectory) {
+ return NS_ERROR_SIGNED_JAR_NOT_SIGNED;
+ }
+
+ // Find and load the Signature (RSA) file
+
+ nsAutoString sigFilename;
+ rv = FindSignatureFilename(metaDir, sigFilename);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ ScopedAutoSECItem sigBuffer;
+ rv = LoadOneMetafile(metaDir, sigFilename, sigBuffer, nullptr);
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_NOT_SIGNED;
+ }
+
+ // Load the signature (SF) file and verify the signature.
+ // The .sf and .rsa files must have the same name apart from the extension.
+
+ nsAutoString sfFilename(Substring(sigFilename, 0, sigFilename.Length() - 3)
+ + NS_LITERAL_STRING("sf"));
+
+ ScopedAutoSECItem sfBuffer;
+ Digest sfCalculatedDigest;
+ rv = LoadOneMetafile(metaDir, sfFilename, sfBuffer, &sfCalculatedDigest);
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ sigBuffer.type = siBuffer;
+ UniqueCERTCertList builtChain;
+ rv = VerifySignature(aTrustedRoot, sigBuffer, sfCalculatedDigest.get(),
+ builtChain);
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // Get the expected manifest hash from the signed .sf file
+
+ ScopedAutoSECItem mfDigest;
+ rv = ParseSF(BitwiseCast<char*, unsigned char*>(sfBuffer.data), mfDigest);
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // Load manifest (MF) file and verify signature
+
+ nsAutoString mfFilename(NS_LITERAL_STRING("manifest.mf"));
+ ScopedAutoSECItem manifestBuffer;
+ Digest mfCalculatedDigest;
+ rv = LoadOneMetafile(metaDir, mfFilename, manifestBuffer, &mfCalculatedDigest);
+ if (NS_FAILED(rv)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ if (SECITEM_CompareItem(&mfDigest, &mfCalculatedDigest.get()) != SECEqual) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // Parse manifest and verify signed hash of all listed files
+
+ // Allocate the I/O buffer only once per JAR, instead of once per entry, in
+ // order to minimize malloc/free calls and in order to avoid fragmenting
+ // memory.
+ ScopedAutoSECItem buf(128 * 1024);
+
+ nsTHashtable<nsStringHashKey> items;
+ rv = ParseMFUnpacked(BitwiseCast<char*, unsigned char*>(manifestBuffer.data),
+ aDirectory, items, buf);
+ if (NS_FAILED(rv)){
+ return rv;
+ }
+
+ // We've checked that everything listed in the manifest exists and is signed
+ // correctly. Now check on disk for extra (unsigned) files.
+ // Deletes found entries from items as it goes.
+ rv = CheckDirForUnsignedFiles(aDirectory, EmptyString(), items,
+ sigFilename, sfFilename, mfFilename);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // We verified that every entry that we require to be signed is signed. But,
+ // were there any missing entries--that is, entries that are mentioned in the
+ // manifest but missing from the directory tree? (There shouldn't be given
+ // ParseMFUnpacked() checking them all, but it's a cheap sanity check.)
+ if (items.Count() != 0) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_MISSING;
+ }
+
+ // Return the signer's certificate to the reader if they want it.
+ // XXX: We should return an nsIX509CertList with the whole validated chain.
+ if (aSignerCert) {
+ CERTCertListNode* signerCertNode = CERT_LIST_HEAD(builtChain);
+ if (!signerCertNode || CERT_LIST_END(signerCertNode, builtChain) ||
+ !signerCertNode->cert) {
+ return NS_ERROR_FAILURE;
+ }
+ nsCOMPtr<nsIX509Cert> signerCert =
+ nsNSSCertificate::Create(signerCertNode->cert);
+ NS_ENSURE_TRUE(signerCert, NS_ERROR_OUT_OF_MEMORY);
+ signerCert.forget(aSignerCert);
+ }
+
+ return NS_OK;
+}
+
+class VerifySignedDirectoryTask final : public CryptoTask
+{
+public:
+ VerifySignedDirectoryTask(AppTrustedRoot aTrustedRoot, nsIFile* aUnpackedJar,
+ nsIVerifySignedDirectoryCallback* aCallback)
+ : mTrustedRoot(aTrustedRoot)
+ , mDirectory(aUnpackedJar)
+ , mCallback(new nsMainThreadPtrHolder<nsIVerifySignedDirectoryCallback>(aCallback))
+ {
+ }
+
+private:
+ virtual nsresult CalculateResult() override
+ {
+ return VerifySignedDirectory(mTrustedRoot,
+ mDirectory,
+ getter_AddRefs(mSignerCert));
+ }
+
+ // This class doesn't directly hold NSS resources so there's nothing that
+ // needs to be released
+ virtual void ReleaseNSSResources() override { }
+
+ virtual void CallCallback(nsresult rv) override
+ {
+ (void) mCallback->VerifySignedDirectoryFinished(rv, mSignerCert);
+ }
+
+ const AppTrustedRoot mTrustedRoot;
+ const nsCOMPtr<nsIFile> mDirectory;
+ nsMainThreadPtrHandle<nsIVerifySignedDirectoryCallback> mCallback;
+ nsCOMPtr<nsIX509Cert> mSignerCert; // out
+};
+
+NS_IMETHODIMP
+nsNSSCertificateDB::VerifySignedDirectoryAsync(
+ AppTrustedRoot aTrustedRoot, nsIFile* aUnpackedJar,
+ nsIVerifySignedDirectoryCallback* aCallback)
+{
+ NS_ENSURE_ARG_POINTER(aUnpackedJar);
+ NS_ENSURE_ARG_POINTER(aCallback);
+ RefPtr<VerifySignedDirectoryTask> task(new VerifySignedDirectoryTask(aTrustedRoot,
+ aUnpackedJar,
+ aCallback));
+ return task->Dispatch("UnpackedJar");
+}