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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /security/manager/ssl/AppSignatureVerification.cpp
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'security/manager/ssl/AppSignatureVerification.cpp')
-rw-r--r--security/manager/ssl/AppSignatureVerification.cpp1410
1 files changed, 1410 insertions, 0 deletions
diff --git a/security/manager/ssl/AppSignatureVerification.cpp b/security/manager/ssl/AppSignatureVerification.cpp
new file mode 100644
index 0000000000..399516dd9c
--- /dev/null
+++ b/security/manager/ssl/AppSignatureVerification.cpp
@@ -0,0 +1,1410 @@
+/* -*- 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 "SharedCertVerifier.h"
+#include "certdb.h"
+#include "cms.h"
+#include "cosec.h"
+#include "mozilla/Base64.h"
+#include "mozilla/Casting.h"
+#include "mozilla/Logging.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/Unused.h"
+#include "nsCOMPtr.h"
+#include "nsComponentManagerUtils.h"
+#include "nsDependentString.h"
+#include "nsHashKeys.h"
+#include "nsIFile.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 "mozpkix/pkix.h"
+#include "mozpkix/pkixnss.h"
+#include "mozpkix/pkixutil.h"
+#include "secerr.h"
+#include "secmime.h"
+
+using namespace mozilla::pkix;
+using namespace mozilla;
+using namespace mozilla::psm;
+
+extern mozilla::LazyLogModule gPIPNSSLog;
+
+namespace {
+
+// A convenient way to pair the bytes of a digest with the algorithm that
+// purportedly produced those bytes. Only SHA-1 and SHA-256 are supported.
+struct DigestWithAlgorithm {
+ nsresult ValidateLength() const {
+ size_t hashLen;
+ switch (mAlgorithm) {
+ case SEC_OID_SHA256:
+ hashLen = SHA256_LENGTH;
+ break;
+ case SEC_OID_SHA1:
+ hashLen = SHA1_LENGTH;
+ break;
+ default:
+ MOZ_ASSERT_UNREACHABLE(
+ "unsupported hash type in DigestWithAlgorithm::ValidateLength");
+ return NS_ERROR_FAILURE;
+ }
+ if (mDigest.Length() != hashLen) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+ return NS_OK;
+ }
+
+ nsAutoCString mDigest;
+ SECOidTag mAlgorithm;
+};
+
+// The digest must have a lifetime greater than or equal to the returned string.
+inline nsDependentCSubstring DigestToDependentString(
+ nsTArray<uint8_t>& digest) {
+ return nsDependentCSubstring(BitwiseCast<char*, uint8_t*>(digest.Elements()),
+ digest.Length());
+}
+
+// Reads a maximum of 8MB from a stream into the supplied buffer.
+// The reason for the 8MB 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 8MB (which
+ // should be much larger than necessary for our purposes) to avoid OOM.
+ static const uint32_t MAX_LENGTH = 8 * 1000 * 1000;
+ 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 loads it. Fails if there are no matches or if
+// there is more than one match. If bufDigest is not null then on success
+// bufDigest will contain the digeset of the entry using the given digest
+// algorithm.
+nsresult FindAndLoadOneEntry(
+ nsIZipReader* zip, const nsACString& searchPattern,
+ /*out*/ nsACString& filename,
+ /*out*/ SECItem& buf,
+ /*optional, in*/ SECOidTag digestAlgorithm = SEC_OID_SHA1,
+ /*optional, out*/ nsTArray<uint8_t>* bufDigest = nullptr) {
+ 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 = Digest::DigestBuf(digestAlgorithm,
+ Span<uint8_t>{buf.data, buf.len - 1}, *bufDigest);
+ 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 DigestWithAlgorithm& digestFromManifest,
+ SECItem& buf) {
+ MOZ_ASSERT(buf.len > 0);
+ nsresult rv = digestFromManifest.ValidateLength();
+ if (NS_FAILED(rv)) {
+ return 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;
+ }
+
+ Digest digest;
+
+ rv = digest.Begin(digestFromManifest.mAlgorithm);
+ 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 = digest.Update(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.
+ nsTArray<uint8_t> outArray;
+ rv = digest.End(outArray);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ nsDependentCSubstring digestStr(DigestToDependentString(outArray));
+ if (!digestStr.Equals(digestFromManifest.mDigest)) {
+ return NS_ERROR_SIGNED_JAR_MODIFIED_ENTRY;
+ }
+
+ return NS_OK;
+}
+
+nsresult VerifyEntryContentDigest(nsIZipReader* zip,
+ const nsACString& aFilename,
+ const DigestWithAlgorithm& 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);
+}
+
+// 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 = 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)$"
+#define JAR_COSE_MF_SEARCH_STRING "(M|/M)ETA-INF/cose.manifest$"
+#define JAR_SF_SEARCH_STRING "(M|/M)ETA-INF/*.(SF|sf)$"
+#define JAR_RSA_SEARCH_STRING "(M|/M)ETA-INF/*.(RSA|rsa)$"
+#define JAR_COSE_SEARCH_STRING "(M|/M)ETA-INF/cose.sig$"
+#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) based on the JDK 8 JAR Specification.
+//
+// The SF file must contain a SHA*-Digest-Manifest attribute in the main
+// section (where the * is either 1 or 256, depending on the given digest
+// algorithm). 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.
+//
+// filebuf must be null-terminated. On output, mfDigest will contain the
+// decoded value of the appropriate SHA*-DigestManifest, if found.
+nsresult ParseSF(const char* filebuf, SECOidTag digestAlgorithm,
+ /*out*/ nsAutoCString& mfDigest) {
+ const char* digestNameToFind = nullptr;
+ switch (digestAlgorithm) {
+ case SEC_OID_SHA256:
+ digestNameToFind = "sha256-digest-manifest";
+ break;
+ case SEC_OID_SHA1:
+ digestNameToFind = "sha1-digest-manifest";
+ break;
+ default:
+ MOZ_ASSERT_UNREACHABLE("bad argument to ParseSF");
+ return NS_ERROR_FAILURE;
+ }
+
+ const char* nextLineStart = filebuf;
+ nsresult rv =
+ CheckManifestVersion(nextLineStart, nsLiteralCString(JAR_SF_HEADER));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ 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). We didn't find the
+ // SHA*-Digest-Manifest we were looking for.
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ nsAutoCString attrName;
+ nsAutoCString attrValue;
+ rv = ParseAttribute(curLine, attrName, attrValue);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ if (attrName.EqualsIgnoreCase(digestNameToFind)) {
+ rv = Base64Decode(attrValue, mfDigest);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // There could be multiple SHA*-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 SHA*-Digest-Manifest
+ // attributes.
+ return NS_OK;
+ }
+
+ // ignore unrecognized attributes
+ }
+
+ MOZ_ASSERT_UNREACHABLE("somehow exited loop in ParseSF without returning");
+ return NS_ERROR_FAILURE;
+}
+
+// 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. Each file's contents are verified against the entry in the manifest with
+// the digest algorithm that matches the given one. This algorithm comes from
+// the signature file. If the signature file has a SHA-256 digest, then SHA-256
+// entries must be present in the manifest file. If the signature file only has
+// a SHA-1 digest, then only SHA-1 digests will be used in the manifest file.
+nsresult ParseMF(const char* filebuf, nsIZipReader* zip,
+ SECOidTag digestAlgorithm,
+ /*out*/ nsTHashtable<nsCStringHashKey>& mfItems,
+ ScopedAutoSECItem& buf) {
+ const char* digestNameToFind = nullptr;
+ switch (digestAlgorithm) {
+ case SEC_OID_SHA256:
+ digestNameToFind = "sha256-digest";
+ break;
+ case SEC_OID_SHA1:
+ digestNameToFind = "sha1-digest";
+ break;
+ default:
+ MOZ_ASSERT_UNREACHABLE("bad argument to ParseMF");
+ return NS_ERROR_FAILURE;
+ }
+
+ const char* nextLineStart = filebuf;
+ nsresult rv =
+ CheckManifestVersion(nextLineStart, nsLiteralCString(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;
+ nsAutoCString 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.IsEmpty()) {
+ // 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.
+ DigestWithAlgorithm digestWithAlgorithm = {digest, digestAlgorithm};
+ rv = VerifyEntryContentDigest(zip, curItemName, digestWithAlgorithm, 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.Truncate();
+
+ 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.EqualsIgnoreCase(digestNameToFind)) {
+ if (!digest.IsEmpty()) { // multiple SHA* digests in section
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ rv = Base64Decode(attrValue, digest);
+ 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;
+}
+
+nsresult VerifyCertificate(Span<const uint8_t> signerCert,
+ AppTrustedRoot trustedRoot,
+ nsTArray<Span<const uint8_t>>&& collectedCerts) {
+ AppTrustDomain trustDomain(std::move(collectedCerts));
+ nsresult rv = trustDomain.SetTrustedRoot(trustedRoot);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ Input certDER;
+ mozilla::pkix::Result result =
+ certDER.Init(signerCert.Elements(), signerCert.Length());
+ if (result != Success) {
+ return mozilla::psm::GetXPCOMFromNSSError(MapResultToPRErrorCode(result));
+ }
+
+ result = BuildCertChain(
+ trustDomain, certDER, Now(), EndEntityOrCA::MustBeEndEntity,
+ KeyUsage::digitalSignature, KeyPurposeId::id_kp_codeSigning,
+ CertPolicyId::anyPolicy, nullptr /*stapledOCSPResponse*/);
+ if (result == mozilla::pkix::Result::ERROR_EXPIRED_CERTIFICATE ||
+ result == mozilla::pkix::Result::ERROR_NOT_YET_VALID_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. Under these conditions it's OK to ignore cert errors related
+ // to time validity (expiration and "not yet valid").
+ //
+ // 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)
+ result = Success;
+ }
+ if (result != Success) {
+ return mozilla::psm::GetXPCOMFromNSSError(MapResultToPRErrorCode(result));
+ }
+
+ return NS_OK;
+}
+
+// Given a SECOidTag representing a digest algorithm (either SEC_OID_SHA1 or
+// SEC_OID_SHA256), returns the first signerInfo in the given signedData that
+// purports to have been created using that digest algorithm, or nullptr if
+// there is none.
+// The returned signerInfo is owned by signedData, so the caller must ensure
+// that the lifetime of the signerInfo is contained by the lifetime of the
+// signedData.
+NSSCMSSignerInfo* GetSignerInfoForDigestAlgorithm(NSSCMSSignedData* signedData,
+ SECOidTag digestAlgorithm) {
+ MOZ_ASSERT(digestAlgorithm == SEC_OID_SHA1 ||
+ digestAlgorithm == SEC_OID_SHA256);
+ if (digestAlgorithm != SEC_OID_SHA1 && digestAlgorithm != SEC_OID_SHA256) {
+ return nullptr;
+ }
+
+ int numSigners = NSS_CMSSignedData_SignerInfoCount(signedData);
+ if (numSigners < 1) {
+ return nullptr;
+ }
+ for (int i = 0; i < numSigners; i++) {
+ NSSCMSSignerInfo* signerInfo =
+ NSS_CMSSignedData_GetSignerInfo(signedData, i);
+ // NSS_CMSSignerInfo_GetDigestAlgTag isn't exported from NSS.
+ SECOidData* digestAlgOID = SECOID_FindOID(&signerInfo->digestAlg.algorithm);
+ if (!digestAlgOID) {
+ continue;
+ }
+ if (digestAlgorithm == digestAlgOID->offset) {
+ return signerInfo;
+ }
+ }
+ return nullptr;
+}
+
+Span<const uint8_t> GetPKCS7SignerCert(
+ NSSCMSSignerInfo* signerInfo,
+ nsTArray<Span<const uint8_t>>& collectedCerts) {
+ if (!signerInfo) {
+ return {};
+ }
+ // The NSS APIs use the term "CMS", but since these are all signed by Mozilla
+ // infrastructure, we know they are actually PKCS7. This means that this only
+ // needs to handle issuer/serial number signer identifiers.
+ if (signerInfo->signerIdentifier.identifierType != NSSCMSSignerID_IssuerSN) {
+ return {};
+ }
+ CERTIssuerAndSN* issuerAndSN = signerInfo->signerIdentifier.id.issuerAndSN;
+ if (!issuerAndSN) {
+ return {};
+ }
+ Input issuer;
+ mozilla::pkix::Result result =
+ issuer.Init(issuerAndSN->derIssuer.data, issuerAndSN->derIssuer.len);
+ if (result != Success) {
+ return {};
+ }
+ Input serialNumber;
+ result = serialNumber.Init(issuerAndSN->serialNumber.data,
+ issuerAndSN->serialNumber.len);
+ if (result != Success) {
+ return {};
+ }
+ for (const auto& certDER : collectedCerts) {
+ Input certInput;
+ result = certInput.Init(certDER.Elements(), certDER.Length());
+ if (result != Success) {
+ continue; // probably too big
+ }
+ // Since this only decodes the certificate and doesn't attempt to build a
+ // verified chain with it, the EndEntityOrCA parameter doesn't matter.
+ BackCert cert(certInput, EndEntityOrCA::MustBeEndEntity, nullptr);
+ result = cert.Init();
+ if (result != Success) {
+ continue;
+ }
+ if (InputsAreEqual(issuer, cert.GetIssuer()) &&
+ InputsAreEqual(serialNumber, cert.GetSerialNumber())) {
+ return certDER;
+ }
+ }
+ return {};
+}
+
+nsresult VerifySignature(AppTrustedRoot trustedRoot, const SECItem& buffer,
+ nsTArray<uint8_t>& detachedSHA1Digest,
+ nsTArray<uint8_t>& detachedSHA256Digest,
+ /*out*/ SECOidTag& digestAlgorithm,
+ /*out*/ nsTArray<uint8_t>& signerCert) {
+ if (NS_WARN_IF(!buffer.data || buffer.len == 0 ||
+ detachedSHA1Digest.Length() == 0 ||
+ detachedSHA256Digest.Length() == 0)) {
+ return NS_ERROR_INVALID_ARG;
+ }
+
+ UniqueNSSCMSMessage cmsMsg(NSS_CMSMessage_CreateFromDER(
+ const_cast<SECItem*>(&buffer), nullptr, nullptr, nullptr, nullptr,
+ nullptr, nullptr));
+ if (!cmsMsg) {
+ return NS_ERROR_CMS_VERIFY_NOT_SIGNED;
+ }
+
+ if (!NSS_CMSMessage_IsSigned(cmsMsg.get())) {
+ return NS_ERROR_CMS_VERIFY_NOT_SIGNED;
+ }
+
+ NSSCMSContentInfo* cinfo = NSS_CMSMessage_ContentLevel(cmsMsg.get(), 0);
+ if (!cinfo) {
+ return NS_ERROR_CMS_VERIFY_NO_CONTENT_INFO;
+ }
+
+ // We're expecting this to be a PKCS#7 signedData content info.
+ if (NSS_CMSContentInfo_GetContentTypeTag(cinfo) !=
+ SEC_OID_PKCS7_SIGNED_DATA) {
+ return NS_ERROR_CMS_VERIFY_NO_CONTENT_INFO;
+ }
+
+ // signedData is non-owning
+ NSSCMSSignedData* signedData =
+ static_cast<NSSCMSSignedData*>(NSS_CMSContentInfo_GetContent(cinfo));
+ if (!signedData) {
+ return NS_ERROR_CMS_VERIFY_NO_CONTENT_INFO;
+ }
+
+ nsTArray<Span<const uint8_t>> collectedCerts;
+ if (signedData->rawCerts) {
+ for (size_t i = 0; signedData->rawCerts[i]; ++i) {
+ Span<const uint8_t> cert(signedData->rawCerts[i]->data,
+ signedData->rawCerts[i]->len);
+ collectedCerts.AppendElement(std::move(cert));
+ }
+ }
+
+ NSSCMSSignerInfo* signerInfo =
+ GetSignerInfoForDigestAlgorithm(signedData, SEC_OID_SHA256);
+ nsTArray<uint8_t>* tmpDetachedDigest = &detachedSHA256Digest;
+ digestAlgorithm = SEC_OID_SHA256;
+ if (!signerInfo) {
+ signerInfo = GetSignerInfoForDigestAlgorithm(signedData, SEC_OID_SHA1);
+ if (!signerInfo) {
+ return NS_ERROR_CMS_VERIFY_NOT_SIGNED;
+ }
+ tmpDetachedDigest = &detachedSHA1Digest;
+ digestAlgorithm = SEC_OID_SHA1;
+ }
+
+ const SECItem detachedDigest = {
+ siBuffer, tmpDetachedDigest->Elements(),
+ static_cast<unsigned int>(tmpDetachedDigest->Length())};
+
+ // Get the certificate that issued the PKCS7 signature.
+ Span<const uint8_t> signerCertSpan =
+ GetPKCS7SignerCert(signerInfo, collectedCerts);
+ if (signerCertSpan.IsEmpty()) {
+ return NS_ERROR_CMS_VERIFY_ERROR_PROCESSING;
+ }
+
+ nsresult rv =
+ VerifyCertificate(signerCertSpan, trustedRoot, std::move(collectedCerts));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ signerCert.Clear();
+ signerCert.AppendElements(signerCertSpan);
+
+ // Ensure that the PKCS#7 data OID is present as the PKCS#9 contentType.
+ const char* pkcs7DataOidString = "1.2.840.113549.1.7.1";
+ ScopedAutoSECItem pkcs7DataOid;
+ if (SEC_StringToOID(nullptr, &pkcs7DataOid, pkcs7DataOidString, 0) !=
+ SECSuccess) {
+ return NS_ERROR_CMS_VERIFY_ERROR_PROCESSING;
+ }
+
+ // NSS_CMSSignerInfo_Verify relies on NSS_CMSSignerInfo_GetSigningCertificate
+ // having been called already. This relies on the signing certificate being
+ // decoded as a CERTCertificate.
+ // This assertion should never fail, as this certificate has been
+ // successfully verified, which means it fits in the size of an unsigned int.
+ SECItem signingCertificateItem = {
+ siBuffer, const_cast<unsigned char*>(signerCertSpan.Elements()),
+ AssertedCast<unsigned int>(signerCertSpan.Length())};
+ UniqueCERTCertificate signingCertificateHandle(CERT_NewTempCertificate(
+ CERT_GetDefaultCertDB(), &signingCertificateItem, nullptr, false, true));
+ if (!signingCertificateHandle) {
+ return mozilla::psm::GetXPCOMFromNSSError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ }
+ // NB: This function does not return an owning reference, unlike with many
+ // other NSS APIs.
+ if (!NSS_CMSSignerInfo_GetSigningCertificate(signerInfo,
+ CERT_GetDefaultCertDB())) {
+ return mozilla::psm::GetXPCOMFromNSSError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ }
+ return MapSECStatus(NSS_CMSSignerInfo_Verify(
+ signerInfo, const_cast<SECItem*>(&detachedDigest), &pkcs7DataOid));
+}
+
+class CoseVerificationContext {
+ public:
+ explicit CoseVerificationContext(AppTrustedRoot aTrustedRoot)
+ : mTrustedRoot(aTrustedRoot) {}
+ ~CoseVerificationContext() = default;
+
+ AppTrustedRoot GetTrustedRoot() { return mTrustedRoot; }
+ void SetCert(Span<const uint8_t> certDER) {
+ mCertDER.Clear();
+ mCertDER.AppendElements(certDER);
+ }
+
+ nsTArray<uint8_t> TakeCert() { return std::move(mCertDER); }
+
+ private:
+ AppTrustedRoot mTrustedRoot;
+ nsTArray<uint8_t> mCertDER;
+};
+
+// Verification function called from cose-rust.
+// Returns true if everything goes well and the signature and certificate chain
+// are good, false in any other case.
+bool CoseVerificationCallback(const uint8_t* aPayload, size_t aPayloadLen,
+ const uint8_t** aCertChain, size_t aCertChainLen,
+ const size_t* aCertsLen, const uint8_t* aEECert,
+ size_t aEECertLen, const uint8_t* aSignature,
+ size_t aSignatureLen, uint8_t aSignatureAlgorithm,
+ void* ctx) {
+ if (!ctx || !aPayload || !aEECert || !aSignature) {
+ return false;
+ }
+ // The ctx here is a pointer to a CoseVerificationContext object
+ CoseVerificationContext* context = static_cast<CoseVerificationContext*>(ctx);
+ AppTrustedRoot aTrustedRoot = context->GetTrustedRoot();
+
+ CK_MECHANISM_TYPE mechanism;
+ SECOidTag oid;
+ uint32_t hash_length;
+ SECItem param = {siBuffer, nullptr, 0};
+ switch (aSignatureAlgorithm) {
+ case ES256:
+ mechanism = CKM_ECDSA;
+ oid = SEC_OID_SHA256;
+ hash_length = SHA256_LENGTH;
+ break;
+ case ES384:
+ mechanism = CKM_ECDSA;
+ oid = SEC_OID_SHA384;
+ hash_length = SHA384_LENGTH;
+ break;
+ case ES512:
+ mechanism = CKM_ECDSA;
+ oid = SEC_OID_SHA512;
+ hash_length = SHA512_LENGTH;
+ break;
+ default:
+ return false;
+ }
+
+ uint8_t hashBuf[HASH_LENGTH_MAX];
+ SECStatus rv = PK11_HashBuf(oid, hashBuf, aPayload, aPayloadLen);
+ if (rv != SECSuccess) {
+ return false;
+ }
+ SECItem hashItem = {siBuffer, hashBuf, hash_length};
+ Input certInput;
+ if (certInput.Init(aEECert, aEECertLen) != Success) {
+ return false;
+ }
+ // Since this only decodes the certificate and doesn't attempt to build a
+ // verified chain with it, the EndEntityOrCA parameter doesn't matter.
+ BackCert backCert(certInput, EndEntityOrCA::MustBeEndEntity, nullptr);
+ if (backCert.Init() != Success) {
+ return false;
+ }
+ Input spkiInput = backCert.GetSubjectPublicKeyInfo();
+ SECItem spkiItem = {siBuffer, const_cast<uint8_t*>(spkiInput.UnsafeGetData()),
+ spkiInput.GetLength()};
+ UniqueCERTSubjectPublicKeyInfo spki(
+ SECKEY_DecodeDERSubjectPublicKeyInfo(&spkiItem));
+ if (!spki) {
+ return false;
+ }
+ UniqueSECKEYPublicKey key(SECKEY_ExtractPublicKey(spki.get()));
+ SECItem signatureItem = {siBuffer, const_cast<uint8_t*>(aSignature),
+ static_cast<unsigned int>(aSignatureLen)};
+ rv = PK11_VerifyWithMechanism(key.get(), mechanism, &param, &signatureItem,
+ &hashItem, nullptr);
+ if (rv != SECSuccess) {
+ return false;
+ }
+
+ nsTArray<Span<const uint8_t>> collectedCerts;
+ for (size_t i = 0; i < aCertChainLen; ++i) {
+ Span<const uint8_t> cert(aCertChain[i], aCertsLen[i]);
+ collectedCerts.AppendElement(std::move(cert));
+ }
+
+ Span<const uint8_t> certSpan = {aEECert, aEECertLen};
+ nsresult nrv =
+ VerifyCertificate(certSpan, aTrustedRoot, std::move(collectedCerts));
+ bool result = true;
+ if (NS_FAILED(nrv)) {
+ result = false;
+ }
+
+ // Passing back the signing certificate in form of the DER cert.
+ context->SetCert(certSpan);
+ if (NS_FAILED(nrv)) {
+ result = false;
+ }
+
+ return result;
+}
+
+nsresult VerifyAppManifest(SECOidTag aDigestToUse, nsCOMPtr<nsIZipReader> aZip,
+ nsTHashtable<nsCStringHashKey>& aIgnoredFiles,
+ const SECItem& aManifestBuffer) {
+ // 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;
+
+ nsresult rv =
+ ParseMF(BitwiseCast<char*, unsigned char*>(aManifestBuffer.data), aZip,
+ aDigestToUse, items, buf);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Verify every entry in the file.
+ nsCOMPtr<nsIUTF8StringEnumerator> entries;
+ rv = aZip->FindEntries(""_ns, getter_AddRefs(entries));
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ if (!entries) {
+ return NS_ERROR_UNEXPECTED;
+ }
+
+ 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()));
+
+ if (entryFilename.Length() == 0) {
+ return NS_ERROR_SIGNED_JAR_ENTRY_INVALID;
+ }
+
+ // The files that comprise the signature mechanism are not covered by the
+ // signature. Ignore these files.
+ if (aIgnoredFiles.Contains(entryFilename)) {
+ continue;
+ }
+
+ // Entries with names that end in "/" are directory entries, which are not
+ // signed.
+ //
+ // Since bug 1415991 we don't support unpacked JARs. The "/" entries are
+ // therefore harmless.
+ if (entryFilename.Last() == '/') {
+ 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 NS_OK;
+}
+
+// This corresponds to the preference "security.signed_app_signatures.policy".
+// The lowest order bit determines which PKCS#7 algorithms are accepted.
+// xxx_0_: SHA-1 and/or SHA-256 PKCS#7 allowed
+// xxx_1_: SHA-256 PKCS#7 allowed
+// The next two bits determine whether COSE is required and PKCS#7 is allowed
+// x_00_x: COSE disabled, ignore files, PKCS#7 must verify
+// x_01_x: COSE is verified if present, PKCS#7 must verify
+// x_10_x: COSE is required, PKCS#7 must verify if present
+// x_11_x: COSE is required, PKCS#7 disabled (fail when present)
+class SignaturePolicy {
+ public:
+ explicit SignaturePolicy(int32_t preference)
+ : mProcessCose(true),
+ mCoseRequired(false),
+ mProcessPK7(true),
+ mPK7Required(true),
+ mSHA1Allowed(true),
+ mSHA256Allowed(true) {
+ mCoseRequired = (preference & 0b100) != 0;
+ mProcessCose = (preference & 0b110) != 0;
+ mPK7Required = (preference & 0b100) == 0;
+ mProcessPK7 = (preference & 0b110) != 0b110;
+ if ((preference & 0b1) == 0) {
+ mSHA1Allowed = true;
+ mSHA256Allowed = true;
+ } else {
+ mSHA1Allowed = false;
+ mSHA256Allowed = true;
+ }
+ }
+ ~SignaturePolicy() = default;
+ bool ProcessCOSE() { return mProcessCose; }
+ bool COSERequired() { return mCoseRequired; }
+ bool PK7Required() { return mPK7Required; }
+ bool ProcessPK7() { return mProcessPK7; }
+ bool IsPK7HashAllowed(SECOidTag aHashAlg) {
+ if (aHashAlg == SEC_OID_SHA256 && mSHA256Allowed) {
+ return true;
+ }
+ if (aHashAlg == SEC_OID_SHA1 && mSHA1Allowed) {
+ return true;
+ }
+ return false;
+ }
+
+ private:
+ bool mProcessCose;
+ bool mCoseRequired;
+ bool mProcessPK7;
+ bool mPK7Required;
+ bool mSHA1Allowed;
+ bool mSHA256Allowed;
+};
+
+nsresult VerifyCOSESignature(AppTrustedRoot aTrustedRoot, nsIZipReader* aZip,
+ SignaturePolicy& aPolicy,
+ nsTHashtable<nsCStringHashKey>& aIgnoredFiles,
+ /* out */ bool& aVerified,
+ /* out */ nsTArray<uint8_t>& aCoseCertDER) {
+ NS_ENSURE_ARG_POINTER(aZip);
+ bool required = aPolicy.COSERequired();
+ aVerified = false;
+
+ // Read COSE signature file.
+ nsAutoCString coseFilename;
+ ScopedAutoSECItem coseBuffer;
+ nsresult rv = FindAndLoadOneEntry(
+ aZip, nsLiteralCString(JAR_COSE_SEARCH_STRING), coseFilename, coseBuffer);
+ if (NS_FAILED(rv)) {
+ return required ? NS_ERROR_SIGNED_JAR_WRONG_SIGNATURE : NS_OK;
+ }
+
+ // Verify COSE signature.
+ nsAutoCString mfFilename;
+ ScopedAutoSECItem manifestBuffer;
+ rv = FindAndLoadOneEntry(aZip, nsLiteralCString(JAR_COSE_MF_SEARCH_STRING),
+ mfFilename, manifestBuffer);
+ if (NS_FAILED(rv)) {
+ return required ? NS_ERROR_SIGNED_JAR_WRONG_SIGNATURE : rv;
+ }
+ MOZ_ASSERT(manifestBuffer.len >= 1);
+ MOZ_ASSERT(coseBuffer.len >= 1);
+ CoseVerificationContext context(aTrustedRoot);
+ bool coseVerification = verify_cose_signature_ffi(
+ manifestBuffer.data, manifestBuffer.len - 1, coseBuffer.data,
+ coseBuffer.len - 1, &context, CoseVerificationCallback);
+ if (!coseVerification) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+ // CoseVerificationCallback sets the context certificate to the first cert
+ // it encounters.
+ aCoseCertDER = context.TakeCert();
+
+ // aIgnoredFiles contains the PKCS#7 manifest and signature files iff the
+ // PKCS#7 verification was successful.
+ aIgnoredFiles.PutEntry(mfFilename);
+ aIgnoredFiles.PutEntry(coseFilename);
+ rv = VerifyAppManifest(SEC_OID_SHA256, aZip, aIgnoredFiles, manifestBuffer);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ aVerified = true;
+ return NS_OK;
+}
+
+nsresult VerifyPK7Signature(
+ AppTrustedRoot aTrustedRoot, nsIZipReader* aZip, SignaturePolicy& aPolicy,
+ /* out */ nsTHashtable<nsCStringHashKey>& aIgnoredFiles,
+ /* out */ bool& aVerified,
+ /* out */ nsTArray<uint8_t>& aSignerCert) {
+ NS_ENSURE_ARG_POINTER(aZip);
+ bool required = aPolicy.PK7Required();
+ aVerified = false;
+
+ // Signature (RSA) file
+ nsAutoCString sigFilename;
+ ScopedAutoSECItem sigBuffer;
+ nsresult rv = FindAndLoadOneEntry(
+ aZip, nsLiteralCString(JAR_RSA_SEARCH_STRING), sigFilename, sigBuffer);
+ if (NS_FAILED(rv)) {
+ return required ? NS_ERROR_SIGNED_JAR_NOT_SIGNED : NS_OK;
+ }
+
+ // Signature (SF) file
+ nsAutoCString sfFilename;
+ ScopedAutoSECItem sfBuffer;
+ rv = FindAndLoadOneEntry(aZip, nsLiteralCString(JAR_SF_SEARCH_STRING),
+ sfFilename, sfBuffer);
+ if (NS_FAILED(rv)) {
+ return required ? NS_ERROR_SIGNED_JAR_MANIFEST_INVALID : NS_OK;
+ }
+
+ // Calculate both the SHA-1 and SHA-256 hashes of the signature file - we
+ // don't know what algorithm the PKCS#7 signature used.
+ nsTArray<uint8_t> sfCalculatedSHA1Digest;
+ rv = Digest::DigestBuf(SEC_OID_SHA1, sfBuffer.data, sfBuffer.len - 1,
+ sfCalculatedSHA1Digest);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ nsTArray<uint8_t> sfCalculatedSHA256Digest;
+ rv = Digest::DigestBuf(SEC_OID_SHA256, sfBuffer.data, sfBuffer.len - 1,
+ sfCalculatedSHA256Digest);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Verify PKCS#7 signature.
+ // If we get here, the signature has to verify even if PKCS#7 is not required.
+ sigBuffer.type = siBuffer;
+ SECOidTag digestToUse;
+ rv = VerifySignature(aTrustedRoot, sigBuffer, sfCalculatedSHA1Digest,
+ sfCalculatedSHA256Digest, digestToUse, aSignerCert);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Check the digest used for the signature against the policy.
+ if (!aPolicy.IsPK7HashAllowed(digestToUse)) {
+ return NS_ERROR_SIGNED_JAR_WRONG_SIGNATURE;
+ }
+
+ nsAutoCString mfDigest;
+ rv = ParseSF(BitwiseCast<char*, unsigned char*>(sfBuffer.data), digestToUse,
+ mfDigest);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // Read PK7 manifest (MF) file.
+ ScopedAutoSECItem manifestBuffer;
+ nsTArray<uint8_t> digestArray;
+ nsAutoCString mfFilename;
+ rv = FindAndLoadOneEntry(aZip, nsLiteralCString(JAR_MF_SEARCH_STRING),
+ mfFilename, manifestBuffer, digestToUse,
+ &digestArray);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ nsDependentCSubstring calculatedDigest(
+ BitwiseCast<char*, uint8_t*>(digestArray.Elements()),
+ digestArray.Length());
+ if (!mfDigest.Equals(calculatedDigest)) {
+ return NS_ERROR_SIGNED_JAR_MANIFEST_INVALID;
+ }
+
+ // Verify PKCS7 manifest file hashes.
+ aIgnoredFiles.PutEntry(sfFilename);
+ aIgnoredFiles.PutEntry(sigFilename);
+ aIgnoredFiles.PutEntry(mfFilename);
+ rv = VerifyAppManifest(digestToUse, aZip, aIgnoredFiles, manifestBuffer);
+ if (NS_FAILED(rv)) {
+ aIgnoredFiles.Clear();
+ return rv;
+ }
+
+ aVerified = true;
+ return NS_OK;
+}
+
+nsresult OpenSignedAppFile(AppTrustedRoot aTrustedRoot, nsIFile* aJarFile,
+ SignaturePolicy aPolicy,
+ /* 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);
+
+ bool pk7Verified = false;
+ bool coseVerified = false;
+ nsTHashtable<nsCStringHashKey> ignoredFiles;
+ nsTArray<uint8_t> pkcs7CertDER;
+ nsTArray<uint8_t> coseCertDER;
+
+ // First we have to verify the PKCS#7 signature if there is one.
+ // This signature covers all files (except for the signature files itself),
+ // including the COSE signature files. Only when this verification is
+ // successful the respective files will be ignored in the subsequent COSE
+ // signature verification.
+ if (aPolicy.ProcessPK7()) {
+ rv = VerifyPK7Signature(aTrustedRoot, zip, aPolicy, ignoredFiles,
+ pk7Verified, pkcs7CertDER);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ }
+
+ if (aPolicy.ProcessCOSE()) {
+ rv = VerifyCOSESignature(aTrustedRoot, zip, aPolicy, ignoredFiles,
+ coseVerified, coseCertDER);
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+ }
+
+ // Bits 1 and 2
+ // 00 = Didn't Process PKCS#7 signatures
+ // 01 = Processed but no valid cert or signature
+ // 10 = Processed and valid cert found, but addon didn't match manifest
+ // 11 = Processed and valid.
+ // Bits 3 and 4 are the same but for COSE.
+ uint32_t bucket = 0;
+ bucket += aPolicy.ProcessCOSE();
+ bucket += !coseCertDER.IsEmpty();
+ bucket += coseVerified;
+ bucket <<= 2;
+ bucket += aPolicy.ProcessPK7();
+ bucket += !pkcs7CertDER.IsEmpty();
+ bucket += pk7Verified;
+ Telemetry::Accumulate(Telemetry::ADDON_SIGNATURE_VERIFICATION_STATUS, bucket);
+
+ if ((aPolicy.PK7Required() && !pk7Verified) ||
+ (aPolicy.COSERequired() && !coseVerified)) {
+ return NS_ERROR_SIGNED_JAR_WRONG_SIGNATURE;
+ }
+
+ // 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.
+ if (aSignerCert) {
+ // The COSE certificate is authoritative.
+ if (aPolicy.COSERequired() || !coseCertDER.IsEmpty()) {
+ if (coseCertDER.IsEmpty()) {
+ return NS_ERROR_FAILURE;
+ }
+ nsCOMPtr<nsIX509Cert> signerCert(
+ new nsNSSCertificate(std::move(coseCertDER)));
+ signerCert.forget(aSignerCert);
+ } else {
+ if (pkcs7CertDER.IsEmpty()) {
+ return NS_ERROR_FAILURE;
+ }
+ nsCOMPtr<nsIX509Cert> signerCert(
+ new nsNSSCertificate(std::move(pkcs7CertDER)));
+ signerCert.forget(aSignerCert);
+ }
+ }
+
+ return NS_OK;
+}
+
+class OpenSignedAppFileTask final : public CryptoTask {
+ public:
+ OpenSignedAppFileTask(AppTrustedRoot aTrustedRoot, nsIFile* aJarFile,
+ SignaturePolicy aPolicy,
+ nsIOpenSignedAppFileCallback* aCallback)
+ : mTrustedRoot(aTrustedRoot),
+ mJarFile(aJarFile),
+ mPolicy(aPolicy),
+ mCallback(new nsMainThreadPtrHolder<nsIOpenSignedAppFileCallback>(
+ "OpenSignedAppFileTask::mCallback", aCallback)) {}
+
+ private:
+ virtual nsresult CalculateResult() override {
+ return OpenSignedAppFile(mTrustedRoot, mJarFile, mPolicy,
+ getter_AddRefs(mZipReader),
+ getter_AddRefs(mSignerCert));
+ }
+
+ virtual void CallCallback(nsresult rv) override {
+ (void)mCallback->OpenSignedAppFileFinished(rv, mZipReader, mSignerCert);
+ }
+
+ const AppTrustedRoot mTrustedRoot;
+ const nsCOMPtr<nsIFile> mJarFile;
+ const SignaturePolicy mPolicy;
+ nsMainThreadPtrHandle<nsIOpenSignedAppFileCallback> mCallback;
+ nsCOMPtr<nsIZipReader> mZipReader; // out
+ nsCOMPtr<nsIX509Cert> mSignerCert; // out
+};
+
+static const int32_t sDefaultSignaturePolicy = 0b10;
+
+} // unnamed namespace
+
+NS_IMETHODIMP
+nsNSSCertificateDB::OpenSignedAppFileAsync(
+ AppTrustedRoot aTrustedRoot, nsIFile* aJarFile,
+ nsIOpenSignedAppFileCallback* aCallback) {
+ NS_ENSURE_ARG_POINTER(aJarFile);
+ NS_ENSURE_ARG_POINTER(aCallback);
+ if (!NS_IsMainThread()) {
+ return NS_ERROR_NOT_SAME_THREAD;
+ }
+ int32_t policyInt =
+ Preferences::GetInt("security.signed_app_signatures.policy",
+ static_cast<int32_t>(sDefaultSignaturePolicy));
+ SignaturePolicy policy(policyInt);
+ RefPtr<OpenSignedAppFileTask> task(
+ new OpenSignedAppFileTask(aTrustedRoot, aJarFile, policy, aCallback));
+ return task->Dispatch();
+}