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-rw-r--r--security/nss/lib/pkcs7/p7decode.c1919
1 files changed, 1919 insertions, 0 deletions
diff --git a/security/nss/lib/pkcs7/p7decode.c b/security/nss/lib/pkcs7/p7decode.c
new file mode 100644
index 0000000000..641d201e5a
--- /dev/null
+++ b/security/nss/lib/pkcs7/p7decode.c
@@ -0,0 +1,1919 @@
+/* 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/. */
+
+/*
+ * PKCS7 decoding, verification.
+ */
+
+#include "p7local.h"
+
+#include "cert.h"
+/* XXX do not want to have to include */
+#include "certdb.h" /* certdb.h -- the trust stuff needed by */
+ /* the add certificate code needs to get */
+ /* rewritten/abstracted and then this */
+ /* include should be removed! */
+/*#include "cdbhdl.h" */
+#include "cryptohi.h"
+#include "keyhi.h"
+#include "secasn1.h"
+#include "secitem.h"
+#include "secoid.h"
+#include "pk11func.h"
+#include "prtime.h"
+#include "secerr.h"
+#include "sechash.h" /* for HASH_GetHashObject() */
+#include "secder.h"
+#include "secpkcs5.h"
+
+struct sec_pkcs7_decoder_worker {
+ int depth;
+ int digcnt;
+ void **digcxs;
+ const SECHashObject **digobjs;
+ sec_PKCS7CipherObject *decryptobj;
+ PRBool saw_contents;
+};
+
+struct SEC_PKCS7DecoderContextStr {
+ SEC_ASN1DecoderContext *dcx;
+ SEC_PKCS7ContentInfo *cinfo;
+ SEC_PKCS7DecoderContentCallback cb;
+ void *cb_arg;
+ SECKEYGetPasswordKey pwfn;
+ void *pwfn_arg;
+ struct sec_pkcs7_decoder_worker worker;
+ PLArenaPool *tmp_poolp;
+ int error;
+ SEC_PKCS7GetDecryptKeyCallback dkcb;
+ void *dkcb_arg;
+ SEC_PKCS7DecryptionAllowedCallback decrypt_allowed_cb;
+};
+
+/*
+ * Handle one worker, decrypting and digesting the data as necessary.
+ *
+ * XXX If/when we support nested contents, this probably needs to be
+ * revised somewhat to get passed the content-info (which unfortunately
+ * can be two different types depending on whether it is encrypted or not)
+ * corresponding to the given worker.
+ */
+static void
+sec_pkcs7_decoder_work_data(SEC_PKCS7DecoderContext *p7dcx,
+ struct sec_pkcs7_decoder_worker *worker,
+ const unsigned char *data, unsigned long len,
+ PRBool final)
+{
+ unsigned char *buf = NULL;
+ SECStatus rv;
+ int i;
+
+ /*
+ * We should really have data to process, or we should be trying
+ * to finish/flush the last block. (This is an overly paranoid
+ * check since all callers are in this file and simple inspection
+ * proves they do it right. But it could find a bug in future
+ * modifications/development, that is why it is here.)
+ */
+ PORT_Assert((data != NULL && len) || final);
+
+ /*
+ * Decrypt this chunk.
+ *
+ * XXX If we get an error, we do not want to do the digest or callback,
+ * but we want to keep decoding. Or maybe we want to stop decoding
+ * altogether if there is a callback, because obviously we are not
+ * sending the data back and they want to know that.
+ */
+ if (worker->decryptobj != NULL) {
+ /* XXX the following lengths should all be longs? */
+ unsigned int inlen; /* length of data being decrypted */
+ unsigned int outlen; /* length of decrypted data */
+ unsigned int buflen; /* length available for decrypted data */
+ SECItem *plain;
+
+ inlen = len;
+ buflen = sec_PKCS7DecryptLength(worker->decryptobj, inlen, final);
+ if (buflen == 0) {
+ if (inlen == 0) /* no input and no output */
+ return;
+ /*
+ * No output is expected, but the input data may be buffered
+ * so we still have to call Decrypt.
+ */
+ rv = sec_PKCS7Decrypt(worker->decryptobj, NULL, NULL, 0,
+ data, inlen, final);
+ if (rv != SECSuccess) {
+ p7dcx->error = PORT_GetError();
+ return; /* XXX indicate error? */
+ }
+ return;
+ }
+
+ if (p7dcx->cb != NULL) {
+ buf = (unsigned char *)PORT_Alloc(buflen);
+ plain = NULL;
+ } else {
+ unsigned long oldlen;
+
+ /*
+ * XXX This assumes one level of content only.
+ * See comment above about nested content types.
+ * XXX Also, it should work for signedAndEnvelopedData, too!
+ */
+ plain = &(p7dcx->cinfo->content.envelopedData->encContentInfo.plainContent);
+
+ oldlen = plain->len;
+ if (oldlen == 0) {
+ buf = (unsigned char *)PORT_ArenaAlloc(p7dcx->cinfo->poolp,
+ buflen);
+ } else {
+ buf = (unsigned char *)PORT_ArenaGrow(p7dcx->cinfo->poolp,
+ plain->data,
+ oldlen, oldlen + buflen);
+ if (buf != NULL)
+ buf += oldlen;
+ }
+ plain->data = buf;
+ }
+ if (buf == NULL) {
+ p7dcx->error = SEC_ERROR_NO_MEMORY;
+ return; /* XXX indicate error? */
+ }
+ rv = sec_PKCS7Decrypt(worker->decryptobj, buf, &outlen, buflen,
+ data, inlen, final);
+ if (rv != SECSuccess) {
+ p7dcx->error = PORT_GetError();
+ return; /* XXX indicate error? */
+ }
+ if (plain != NULL) {
+ PORT_Assert(final || outlen == buflen);
+ plain->len += outlen;
+ }
+ data = buf;
+ len = outlen;
+ }
+
+ /*
+ * Update the running digests.
+ */
+ if (len) {
+ for (i = 0; i < worker->digcnt; i++) {
+ (*worker->digobjs[i]->update)(worker->digcxs[i], data, len);
+ }
+ }
+
+ /*
+ * Pass back the contents bytes, and free the temporary buffer.
+ */
+ if (p7dcx->cb != NULL) {
+ if (len)
+ (*p7dcx->cb)(p7dcx->cb_arg, (const char *)data, len);
+ if (worker->decryptobj != NULL) {
+ PORT_Assert(buf != NULL);
+ PORT_Free(buf);
+ }
+ }
+}
+
+static void
+sec_pkcs7_decoder_filter(void *arg, const char *data, unsigned long len,
+ int depth, SEC_ASN1EncodingPart data_kind)
+{
+ SEC_PKCS7DecoderContext *p7dcx;
+ struct sec_pkcs7_decoder_worker *worker;
+
+ /*
+ * Since we do not handle any nested contents, the only bytes we
+ * are really interested in are the actual contents bytes (not
+ * the identifier, length, or end-of-contents bytes). If we were
+ * handling nested types we would probably need to do something
+ * smarter based on depth and data_kind.
+ */
+ if (data_kind != SEC_ASN1_Contents)
+ return;
+
+ /*
+ * The ASN.1 decoder should not even call us with a length of 0.
+ * Just being paranoid.
+ */
+ PORT_Assert(len);
+ if (len == 0)
+ return;
+
+ p7dcx = (SEC_PKCS7DecoderContext *)arg;
+
+ /*
+ * Handling nested contents would mean that there is a chain
+ * of workers -- one per each level of content. The following
+ * would start with the first worker and loop over them.
+ */
+ worker = &(p7dcx->worker);
+
+ worker->saw_contents = PR_TRUE;
+
+ sec_pkcs7_decoder_work_data(p7dcx, worker,
+ (const unsigned char *)data, len, PR_FALSE);
+}
+
+/*
+ * Create digest contexts for each algorithm in "digestalgs".
+ * No algorithms is not an error, we just do not do anything.
+ * An error (like trouble allocating memory), marks the error
+ * in "p7dcx" and returns SECFailure, which means that our caller
+ * should just give up altogether.
+ */
+static SECStatus
+sec_pkcs7_decoder_start_digests(SEC_PKCS7DecoderContext *p7dcx, int depth,
+ SECAlgorithmID **digestalgs)
+{
+ int i, digcnt;
+
+ if (digestalgs == NULL)
+ return SECSuccess;
+
+ /*
+ * Count the algorithms.
+ */
+ digcnt = 0;
+ while (digestalgs[digcnt] != NULL)
+ digcnt++;
+
+ /*
+ * No algorithms means no work to do.
+ * Just act as if there were no algorithms specified.
+ */
+ if (digcnt == 0)
+ return SECSuccess;
+
+ p7dcx->worker.digcxs = (void **)PORT_ArenaAlloc(p7dcx->tmp_poolp,
+ digcnt * sizeof(void *));
+ p7dcx->worker.digobjs = (const SECHashObject **)PORT_ArenaAlloc(p7dcx->tmp_poolp,
+ digcnt * sizeof(SECHashObject *));
+ if (p7dcx->worker.digcxs == NULL || p7dcx->worker.digobjs == NULL) {
+ p7dcx->error = SEC_ERROR_NO_MEMORY;
+ return SECFailure;
+ }
+
+ p7dcx->worker.depth = depth;
+ p7dcx->worker.digcnt = 0;
+
+ /*
+ * Create a digest context for each algorithm.
+ */
+ for (i = 0; i < digcnt; i++) {
+ SECAlgorithmID *algid = digestalgs[i];
+ SECOidTag oidTag = SECOID_FindOIDTag(&(algid->algorithm));
+ const SECHashObject *digobj = HASH_GetHashObjectByOidTag(oidTag);
+ void *digcx;
+
+ /*
+ * Skip any algorithm we do not even recognize; obviously,
+ * this could be a problem, but if it is critical then the
+ * result will just be that the signature does not verify.
+ * We do not necessarily want to error out here, because
+ * the particular algorithm may not actually be important,
+ * but we cannot know that until later.
+ */
+ if (digobj == NULL) {
+ p7dcx->worker.digcnt--;
+ continue;
+ }
+
+ digcx = (*digobj->create)();
+ if (digcx != NULL) {
+ (*digobj->begin)(digcx);
+ p7dcx->worker.digobjs[p7dcx->worker.digcnt] = digobj;
+ p7dcx->worker.digcxs[p7dcx->worker.digcnt] = digcx;
+ p7dcx->worker.digcnt++;
+ }
+ }
+
+ if (p7dcx->worker.digcnt != 0)
+ SEC_ASN1DecoderSetFilterProc(p7dcx->dcx,
+ sec_pkcs7_decoder_filter,
+ p7dcx,
+ (PRBool)(p7dcx->cb != NULL));
+ return SECSuccess;
+}
+
+/*
+ * Close out all of the digest contexts, storing the results in "digestsp".
+ */
+static SECStatus
+sec_pkcs7_decoder_finish_digests(SEC_PKCS7DecoderContext *p7dcx,
+ PLArenaPool *poolp,
+ SECItem ***digestsp)
+{
+ struct sec_pkcs7_decoder_worker *worker;
+ const SECHashObject *digobj;
+ void *digcx;
+ SECItem **digests, *digest;
+ int i;
+ void *mark;
+
+ /*
+ * XXX Handling nested contents would mean that there is a chain
+ * of workers -- one per each level of content. The following
+ * would want to find the last worker in the chain.
+ */
+ worker = &(p7dcx->worker);
+
+ /*
+ * If no digests, then we have nothing to do.
+ */
+ if (worker->digcnt == 0)
+ return SECSuccess;
+
+ /*
+ * No matter what happens after this, we want to stop filtering.
+ * XXX If we handle nested contents, we only want to stop filtering
+ * if we are finishing off the *last* worker.
+ */
+ SEC_ASN1DecoderClearFilterProc(p7dcx->dcx);
+
+ /*
+ * If we ended up with no contents, just destroy each
+ * digest context -- they are meaningless and potentially
+ * confusing, because their presence would imply some content
+ * was digested.
+ */
+ if (!worker->saw_contents) {
+ for (i = 0; i < worker->digcnt; i++) {
+ digcx = worker->digcxs[i];
+ digobj = worker->digobjs[i];
+ (*digobj->destroy)(digcx, PR_TRUE);
+ }
+ return SECSuccess;
+ }
+
+ mark = PORT_ArenaMark(poolp);
+
+ /*
+ * Close out each digest context, saving digest away.
+ */
+ digests =
+ (SECItem **)PORT_ArenaAlloc(poolp, (worker->digcnt + 1) * sizeof(SECItem *));
+ digest = (SECItem *)PORT_ArenaAlloc(poolp, worker->digcnt * sizeof(SECItem));
+ if (digests == NULL || digest == NULL) {
+ p7dcx->error = PORT_GetError();
+ PORT_ArenaRelease(poolp, mark);
+ return SECFailure;
+ }
+
+ for (i = 0; i < worker->digcnt; i++, digest++) {
+ digcx = worker->digcxs[i];
+ digobj = worker->digobjs[i];
+
+ digest->data = (unsigned char *)PORT_ArenaAlloc(poolp, digobj->length);
+ if (digest->data == NULL) {
+ p7dcx->error = PORT_GetError();
+ PORT_ArenaRelease(poolp, mark);
+ return SECFailure;
+ }
+
+ digest->len = digobj->length;
+ (*digobj->end)(digcx, digest->data, &(digest->len), digest->len);
+ (*digobj->destroy)(digcx, PR_TRUE);
+
+ digests[i] = digest;
+ }
+ digests[i] = NULL;
+ *digestsp = digests;
+
+ PORT_ArenaUnmark(poolp, mark);
+ return SECSuccess;
+}
+
+/*
+ * XXX Need comment explaining following helper function (which is used
+ * by sec_pkcs7_decoder_start_decrypt).
+ */
+
+static PK11SymKey *
+sec_pkcs7_decoder_get_recipient_key(SEC_PKCS7DecoderContext *p7dcx,
+ SEC_PKCS7RecipientInfo **recipientinfos,
+ SEC_PKCS7EncryptedContentInfo *enccinfo)
+{
+ SEC_PKCS7RecipientInfo *ri;
+ CERTCertificate *cert = NULL;
+ SECKEYPrivateKey *privkey = NULL;
+ PK11SymKey *bulkkey = NULL;
+ SECOidTag keyalgtag, bulkalgtag, encalgtag;
+ PK11SlotInfo *slot = NULL;
+
+ if (recipientinfos == NULL || recipientinfos[0] == NULL) {
+ p7dcx->error = SEC_ERROR_NOT_A_RECIPIENT;
+ goto no_key_found;
+ }
+
+ cert = PK11_FindCertAndKeyByRecipientList(&slot, recipientinfos, &ri,
+ &privkey, p7dcx->pwfn_arg);
+ if (cert == NULL) {
+ p7dcx->error = SEC_ERROR_NOT_A_RECIPIENT;
+ goto no_key_found;
+ }
+
+ ri->cert = cert; /* so we can find it later */
+ PORT_Assert(privkey != NULL);
+
+ keyalgtag = SECOID_GetAlgorithmTag(&(cert->subjectPublicKeyInfo.algorithm));
+ encalgtag = SECOID_GetAlgorithmTag(&(ri->keyEncAlg));
+ if (keyalgtag != encalgtag) {
+ p7dcx->error = SEC_ERROR_PKCS7_KEYALG_MISMATCH;
+ goto no_key_found;
+ }
+ bulkalgtag = SECOID_GetAlgorithmTag(&(enccinfo->contentEncAlg));
+
+ switch (encalgtag) {
+ case SEC_OID_PKCS1_RSA_ENCRYPTION:
+ bulkkey = PK11_PubUnwrapSymKey(privkey, &ri->encKey,
+ PK11_AlgtagToMechanism(bulkalgtag),
+ CKA_DECRYPT, 0);
+ if (bulkkey == NULL) {
+ p7dcx->error = PORT_GetError();
+ PORT_SetError(0);
+ goto no_key_found;
+ }
+ break;
+ default:
+ p7dcx->error = SEC_ERROR_UNSUPPORTED_KEYALG;
+ break;
+ }
+
+no_key_found:
+ if (privkey != NULL)
+ SECKEY_DestroyPrivateKey(privkey);
+ if (slot != NULL)
+ PK11_FreeSlot(slot);
+
+ return bulkkey;
+}
+
+/*
+ * XXX The following comment is old -- the function used to only handle
+ * EnvelopedData or SignedAndEnvelopedData but now handles EncryptedData
+ * as well (and it had all of the code of the helper function above
+ * built into it), though the comment was left as is. Fix it...
+ *
+ * We are just about to decode the content of an EnvelopedData.
+ * Set up a decryption context so we can decrypt as we go.
+ * Presumably we are one of the recipients listed in "recipientinfos".
+ * (XXX And if we are not, or if we have trouble, what should we do?
+ * It would be nice to let the decoding still work. Maybe it should
+ * be an error if there is a content callback, but not an error otherwise?)
+ * The encryption key and related information can be found in "enccinfo".
+ */
+static SECStatus
+sec_pkcs7_decoder_start_decrypt(SEC_PKCS7DecoderContext *p7dcx, int depth,
+ SEC_PKCS7RecipientInfo **recipientinfos,
+ SEC_PKCS7EncryptedContentInfo *enccinfo,
+ PK11SymKey **copy_key_for_signature)
+{
+ PK11SymKey *bulkkey = NULL;
+ sec_PKCS7CipherObject *decryptobj;
+
+ /*
+ * If a callback is supplied to retrieve the encryption key,
+ * for instance, for Encrypted Content infos, then retrieve
+ * the bulkkey from the callback. Otherwise, assume that
+ * we are processing Enveloped or SignedAndEnveloped data
+ * content infos.
+ *
+ * XXX Put an assert here?
+ */
+ if (SEC_PKCS7ContentType(p7dcx->cinfo) == SEC_OID_PKCS7_ENCRYPTED_DATA) {
+ if (p7dcx->dkcb != NULL) {
+ bulkkey = (*p7dcx->dkcb)(p7dcx->dkcb_arg,
+ &(enccinfo->contentEncAlg));
+ }
+ enccinfo->keysize = 0;
+ } else {
+ bulkkey = sec_pkcs7_decoder_get_recipient_key(p7dcx, recipientinfos,
+ enccinfo);
+ if (bulkkey == NULL)
+ goto no_decryption;
+ enccinfo->keysize = PK11_GetKeyStrength(bulkkey,
+ &(enccinfo->contentEncAlg));
+ }
+
+ /*
+ * XXX I think following should set error in p7dcx and clear set error
+ * (as used to be done here, or as is done in get_receipient_key above.
+ */
+ if (bulkkey == NULL) {
+ goto no_decryption;
+ }
+
+ /*
+ * We want to make sure decryption is allowed. This is done via
+ * a callback specified in SEC_PKCS7DecoderStart().
+ */
+ if (p7dcx->decrypt_allowed_cb) {
+ if ((*p7dcx->decrypt_allowed_cb)(&(enccinfo->contentEncAlg),
+ bulkkey) == PR_FALSE) {
+ p7dcx->error = SEC_ERROR_DECRYPTION_DISALLOWED;
+ goto no_decryption;
+ }
+ } else {
+ p7dcx->error = SEC_ERROR_DECRYPTION_DISALLOWED;
+ goto no_decryption;
+ }
+
+ /*
+ * When decrypting a signedAndEnvelopedData, the signature also has
+ * to be decrypted with the bulk encryption key; to avoid having to
+ * get it all over again later (and do another potentially expensive
+ * RSA operation), copy it for later signature verification to use.
+ */
+ if (copy_key_for_signature != NULL)
+ *copy_key_for_signature = PK11_ReferenceSymKey(bulkkey);
+
+ /*
+ * Now we have the bulk encryption key (in bulkkey) and the
+ * the algorithm (in enccinfo->contentEncAlg). Using those,
+ * create a decryption context.
+ */
+ decryptobj = sec_PKCS7CreateDecryptObject(bulkkey,
+ &(enccinfo->contentEncAlg));
+
+ /*
+ * We are done with (this) bulkkey now.
+ */
+ PK11_FreeSymKey(bulkkey);
+
+ if (decryptobj == NULL) {
+ p7dcx->error = PORT_GetError();
+ PORT_SetError(0);
+ goto no_decryption;
+ }
+
+ SEC_ASN1DecoderSetFilterProc(p7dcx->dcx,
+ sec_pkcs7_decoder_filter,
+ p7dcx,
+ (PRBool)(p7dcx->cb != NULL));
+
+ p7dcx->worker.depth = depth;
+ p7dcx->worker.decryptobj = decryptobj;
+
+ return SECSuccess;
+
+no_decryption:
+ PK11_FreeSymKey(bulkkey);
+ /*
+ * For some reason (error set already, if appropriate), we cannot
+ * decrypt the content. I am not sure what exactly is the right
+ * thing to do here; in some cases we want to just stop, and in
+ * others we want to let the decoding finish even though we cannot
+ * decrypt the content. My current thinking is that if the caller
+ * set up a content callback, then they are really interested in
+ * getting (decrypted) content, and if they cannot they will want
+ * to know about it. However, if no callback was specified, then
+ * maybe it is not important that the decryption failed.
+ */
+ if (p7dcx->cb != NULL)
+ return SECFailure;
+ else
+ return SECSuccess; /* Let the decoding continue. */
+}
+
+static SECStatus
+sec_pkcs7_decoder_finish_decrypt(SEC_PKCS7DecoderContext *p7dcx,
+ PLArenaPool *poolp,
+ SEC_PKCS7EncryptedContentInfo *enccinfo)
+{
+ struct sec_pkcs7_decoder_worker *worker;
+
+ /*
+ * XXX Handling nested contents would mean that there is a chain
+ * of workers -- one per each level of content. The following
+ * would want to find the last worker in the chain.
+ */
+ worker = &(p7dcx->worker);
+
+ /*
+ * If no decryption context, then we have nothing to do.
+ */
+ if (worker->decryptobj == NULL)
+ return SECSuccess;
+
+ /*
+ * No matter what happens after this, we want to stop filtering.
+ * XXX If we handle nested contents, we only want to stop filtering
+ * if we are finishing off the *last* worker.
+ */
+ SEC_ASN1DecoderClearFilterProc(p7dcx->dcx);
+
+ /*
+ * Handle the last block.
+ */
+ sec_pkcs7_decoder_work_data(p7dcx, worker, NULL, 0, PR_TRUE);
+
+ /*
+ * All done, destroy it.
+ */
+ sec_PKCS7DestroyDecryptObject(worker->decryptobj);
+ worker->decryptobj = NULL;
+
+ return SECSuccess;
+}
+
+static void
+sec_pkcs7_decoder_notify(void *arg, PRBool before, void *dest, int depth)
+{
+ SEC_PKCS7DecoderContext *p7dcx;
+ SEC_PKCS7ContentInfo *cinfo;
+ SEC_PKCS7SignedData *sigd;
+ SEC_PKCS7EnvelopedData *envd;
+ SEC_PKCS7SignedAndEnvelopedData *saed;
+ SEC_PKCS7EncryptedData *encd;
+ SEC_PKCS7DigestedData *digd;
+ PRBool after;
+ SECStatus rv;
+
+ /*
+ * Just to make the code easier to read, create an "after" variable
+ * that is equivalent to "not before".
+ * (This used to be just the statement "after = !before", but that
+ * causes a warning on the mac; to avoid that, we do it the long way.)
+ */
+ if (before)
+ after = PR_FALSE;
+ else
+ after = PR_TRUE;
+
+ p7dcx = (SEC_PKCS7DecoderContext *)arg;
+ if (!p7dcx) {
+ return;
+ }
+
+ cinfo = p7dcx->cinfo;
+
+ if (!cinfo) {
+ return;
+ }
+
+ if (cinfo->contentTypeTag == NULL) {
+ if (after && dest == &(cinfo->contentType))
+ cinfo->contentTypeTag = SECOID_FindOID(&(cinfo->contentType));
+ return;
+ }
+
+ switch (cinfo->contentTypeTag->offset) {
+ case SEC_OID_PKCS7_SIGNED_DATA:
+ sigd = cinfo->content.signedData;
+ if (sigd == NULL)
+ break;
+
+ if (sigd->contentInfo.contentTypeTag == NULL) {
+ if (after && dest == &(sigd->contentInfo.contentType))
+ sigd->contentInfo.contentTypeTag =
+ SECOID_FindOID(&(sigd->contentInfo.contentType));
+ break;
+ }
+
+ /*
+ * We only set up a filtering digest if the content is
+ * plain DATA; anything else needs more work because a
+ * second pass is required to produce a DER encoding from
+ * an input that can be BER encoded. (This is a requirement
+ * of PKCS7 that is unfortunate, but there you have it.)
+ *
+ * XXX Also, since we stop here if this is not DATA, the
+ * inner content is not getting processed at all. Someday
+ * we may want to fix that.
+ */
+ if (sigd->contentInfo.contentTypeTag->offset != SEC_OID_PKCS7_DATA) {
+ /* XXX Set an error in p7dcx->error */
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+ break;
+ }
+
+ /*
+ * Just before the content, we want to set up a digest context
+ * for each digest algorithm listed, and start a filter which
+ * will run all of the contents bytes through that digest.
+ */
+ if (before && dest == &(sigd->contentInfo.content)) {
+ rv = sec_pkcs7_decoder_start_digests(p7dcx, depth,
+ sigd->digestAlgorithms);
+ if (rv != SECSuccess)
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+
+ break;
+ }
+
+ /*
+ * XXX To handle nested types, here is where we would want
+ * to check for inner boundaries that need handling.
+ */
+
+ /*
+ * Are we done?
+ */
+ if (after && dest == &(sigd->contentInfo.content)) {
+ /*
+ * Close out the digest contexts. We ignore any error
+ * because we are stopping anyway; the error status left
+ * behind in p7dcx will be seen by outer functions.
+ */
+ (void)sec_pkcs7_decoder_finish_digests(p7dcx, cinfo->poolp,
+ &(sigd->digests));
+
+ /*
+ * XXX To handle nested contents, we would need to remove
+ * the worker from the chain (and free it).
+ */
+
+ /*
+ * Stop notify.
+ */
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+ }
+ break;
+
+ case SEC_OID_PKCS7_ENVELOPED_DATA:
+ envd = cinfo->content.envelopedData;
+ if (envd == NULL)
+ break;
+
+ if (envd->encContentInfo.contentTypeTag == NULL) {
+ if (after && dest == &(envd->encContentInfo.contentType))
+ envd->encContentInfo.contentTypeTag =
+ SECOID_FindOID(&(envd->encContentInfo.contentType));
+ break;
+ }
+
+ /*
+ * Just before the content, we want to set up a decryption
+ * context, and start a filter which will run all of the
+ * contents bytes through it to determine the plain content.
+ */
+ if (before && dest == &(envd->encContentInfo.encContent)) {
+ rv = sec_pkcs7_decoder_start_decrypt(p7dcx, depth,
+ envd->recipientInfos,
+ &(envd->encContentInfo),
+ NULL);
+ if (rv != SECSuccess)
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+
+ break;
+ }
+
+ /*
+ * Are we done?
+ */
+ if (after && dest == &(envd->encContentInfo.encContent)) {
+ /*
+ * Close out the decryption context. We ignore any error
+ * because we are stopping anyway; the error status left
+ * behind in p7dcx will be seen by outer functions.
+ */
+ (void)sec_pkcs7_decoder_finish_decrypt(p7dcx, cinfo->poolp,
+ &(envd->encContentInfo));
+
+ /*
+ * XXX To handle nested contents, we would need to remove
+ * the worker from the chain (and free it).
+ */
+
+ /*
+ * Stop notify.
+ */
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+ }
+ break;
+
+ case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
+ saed = cinfo->content.signedAndEnvelopedData;
+ if (saed == NULL)
+ break;
+
+ if (saed->encContentInfo.contentTypeTag == NULL) {
+ if (after && dest == &(saed->encContentInfo.contentType))
+ saed->encContentInfo.contentTypeTag =
+ SECOID_FindOID(&(saed->encContentInfo.contentType));
+ break;
+ }
+
+ /*
+ * Just before the content, we want to set up a decryption
+ * context *and* digest contexts, and start a filter which
+ * will run all of the contents bytes through both.
+ */
+ if (before && dest == &(saed->encContentInfo.encContent)) {
+ rv = sec_pkcs7_decoder_start_decrypt(p7dcx, depth,
+ saed->recipientInfos,
+ &(saed->encContentInfo),
+ &(saed->sigKey));
+ if (rv == SECSuccess)
+ rv = sec_pkcs7_decoder_start_digests(p7dcx, depth,
+ saed->digestAlgorithms);
+ if (rv != SECSuccess)
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+
+ break;
+ }
+
+ /*
+ * Are we done?
+ */
+ if (after && dest == &(saed->encContentInfo.encContent)) {
+ /*
+ * Close out the decryption and digests contexts.
+ * We ignore any errors because we are stopping anyway;
+ * the error status left behind in p7dcx will be seen by
+ * outer functions.
+ *
+ * Note that the decrypt stuff must be called first;
+ * it may have a last buffer to do which in turn has
+ * to be added to the digest.
+ */
+ (void)sec_pkcs7_decoder_finish_decrypt(p7dcx, cinfo->poolp,
+ &(saed->encContentInfo));
+ (void)sec_pkcs7_decoder_finish_digests(p7dcx, cinfo->poolp,
+ &(saed->digests));
+
+ /*
+ * XXX To handle nested contents, we would need to remove
+ * the worker from the chain (and free it).
+ */
+
+ /*
+ * Stop notify.
+ */
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+ }
+ break;
+
+ case SEC_OID_PKCS7_DIGESTED_DATA:
+ digd = cinfo->content.digestedData;
+
+ /*
+ * XXX Want to do the digest or not? Maybe future enhancement...
+ */
+ if (before && dest == &(digd->contentInfo.content.data)) {
+ SEC_ASN1DecoderSetFilterProc(p7dcx->dcx, sec_pkcs7_decoder_filter,
+ p7dcx,
+ (PRBool)(p7dcx->cb != NULL));
+ break;
+ }
+
+ /*
+ * Are we done?
+ */
+ if (after && dest == &(digd->contentInfo.content.data)) {
+ SEC_ASN1DecoderClearFilterProc(p7dcx->dcx);
+ }
+ break;
+
+ case SEC_OID_PKCS7_ENCRYPTED_DATA:
+ encd = cinfo->content.encryptedData;
+
+ if (!encd) {
+ break;
+ }
+
+ /*
+ * XXX If the decryption key callback is set, we want to start
+ * the decryption. If the callback is not set, we will treat the
+ * content as plain data, since we do not have the key.
+ *
+ * Is this the proper thing to do?
+ */
+ if (before && dest == &(encd->encContentInfo.encContent)) {
+ /*
+ * Start the encryption process if the decryption key callback
+ * is present. Otherwise, treat the content like plain data.
+ */
+ rv = SECSuccess;
+ if (p7dcx->dkcb != NULL) {
+ rv = sec_pkcs7_decoder_start_decrypt(p7dcx, depth, NULL,
+ &(encd->encContentInfo),
+ NULL);
+ }
+
+ if (rv != SECSuccess)
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+
+ break;
+ }
+
+ /*
+ * Are we done?
+ */
+ if (after && dest == &(encd->encContentInfo.encContent)) {
+ /*
+ * Close out the decryption context. We ignore any error
+ * because we are stopping anyway; the error status left
+ * behind in p7dcx will be seen by outer functions.
+ */
+ (void)sec_pkcs7_decoder_finish_decrypt(p7dcx, cinfo->poolp,
+ &(encd->encContentInfo));
+
+ /*
+ * Stop notify.
+ */
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+ }
+ break;
+
+ case SEC_OID_PKCS7_DATA:
+ /*
+ * If a output callback has been specified, we want to set the filter
+ * to call the callback. This is taken care of in
+ * sec_pkcs7_decoder_start_decrypt() or
+ * sec_pkcs7_decoder_start_digests() for the other content types.
+ */
+
+ if (before && dest == &(cinfo->content.data)) {
+
+ /*
+ * Set the filter proc up.
+ */
+ SEC_ASN1DecoderSetFilterProc(p7dcx->dcx,
+ sec_pkcs7_decoder_filter,
+ p7dcx,
+ (PRBool)(p7dcx->cb != NULL));
+ break;
+ }
+
+ if (after && dest == &(cinfo->content.data)) {
+ /*
+ * Time to clean up after ourself, stop the Notify and Filter
+ * procedures.
+ */
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+ SEC_ASN1DecoderClearFilterProc(p7dcx->dcx);
+ }
+ break;
+
+ default:
+ SEC_ASN1DecoderClearNotifyProc(p7dcx->dcx);
+ break;
+ }
+}
+
+SEC_PKCS7DecoderContext *
+SEC_PKCS7DecoderStart(SEC_PKCS7DecoderContentCallback cb, void *cb_arg,
+ SECKEYGetPasswordKey pwfn, void *pwfn_arg,
+ SEC_PKCS7GetDecryptKeyCallback decrypt_key_cb,
+ void *decrypt_key_cb_arg,
+ SEC_PKCS7DecryptionAllowedCallback decrypt_allowed_cb)
+{
+ SEC_PKCS7DecoderContext *p7dcx;
+ SEC_ASN1DecoderContext *dcx;
+ SEC_PKCS7ContentInfo *cinfo;
+ PLArenaPool *poolp;
+
+ poolp = PORT_NewArena(1024); /* XXX what is right value? */
+ if (poolp == NULL)
+ return NULL;
+
+ cinfo = (SEC_PKCS7ContentInfo *)PORT_ArenaZAlloc(poolp, sizeof(*cinfo));
+ if (cinfo == NULL) {
+ PORT_FreeArena(poolp, PR_FALSE);
+ return NULL;
+ }
+
+ cinfo->poolp = poolp;
+ cinfo->pwfn = pwfn;
+ cinfo->pwfn_arg = pwfn_arg;
+ cinfo->created = PR_FALSE;
+ cinfo->refCount = 1;
+
+ p7dcx =
+ (SEC_PKCS7DecoderContext *)PORT_ZAlloc(sizeof(SEC_PKCS7DecoderContext));
+ if (p7dcx == NULL) {
+ PORT_FreeArena(poolp, PR_FALSE);
+ return NULL;
+ }
+
+ p7dcx->tmp_poolp = PORT_NewArena(1024); /* XXX what is right value? */
+ if (p7dcx->tmp_poolp == NULL) {
+ PORT_Free(p7dcx);
+ PORT_FreeArena(poolp, PR_FALSE);
+ return NULL;
+ }
+
+ dcx = SEC_ASN1DecoderStart(poolp, cinfo, sec_PKCS7ContentInfoTemplate);
+ if (dcx == NULL) {
+ PORT_FreeArena(p7dcx->tmp_poolp, PR_FALSE);
+ PORT_Free(p7dcx);
+ PORT_FreeArena(poolp, PR_FALSE);
+ return NULL;
+ }
+
+ SEC_ASN1DecoderSetNotifyProc(dcx, sec_pkcs7_decoder_notify, p7dcx);
+
+ p7dcx->dcx = dcx;
+ p7dcx->cinfo = cinfo;
+ p7dcx->cb = cb;
+ p7dcx->cb_arg = cb_arg;
+ p7dcx->pwfn = pwfn;
+ p7dcx->pwfn_arg = pwfn_arg;
+ p7dcx->dkcb = decrypt_key_cb;
+ p7dcx->dkcb_arg = decrypt_key_cb_arg;
+ p7dcx->decrypt_allowed_cb = decrypt_allowed_cb;
+
+ return p7dcx;
+}
+
+/*
+ * Do the next chunk of PKCS7 decoding. If there is a problem, set
+ * an error and return a failure status. Note that in the case of
+ * an error, this routine is still prepared to be called again and
+ * again in case that is the easiest route for our caller to take.
+ * We simply detect it and do not do anything except keep setting
+ * that error in case our caller has not noticed it yet...
+ */
+SECStatus
+SEC_PKCS7DecoderUpdate(SEC_PKCS7DecoderContext *p7dcx,
+ const char *buf, unsigned long len)
+{
+ if (!p7dcx) {
+ PORT_SetError(SEC_ERROR_INVALID_ARGS);
+ return SECFailure;
+ }
+
+ if (p7dcx->cinfo != NULL && p7dcx->dcx != NULL) {
+ PORT_Assert(p7dcx->error == 0);
+ if (p7dcx->error == 0) {
+ if (SEC_ASN1DecoderUpdate(p7dcx->dcx, buf, len) != SECSuccess) {
+ p7dcx->error = PORT_GetError();
+ PORT_Assert(p7dcx->error);
+ if (p7dcx->error == 0)
+ p7dcx->error = -1;
+ }
+ }
+ }
+
+ if (p7dcx->error) {
+ if (p7dcx->dcx != NULL) {
+ (void)SEC_ASN1DecoderFinish(p7dcx->dcx);
+ p7dcx->dcx = NULL;
+ }
+ if (p7dcx->cinfo != NULL) {
+ SEC_PKCS7DestroyContentInfo(p7dcx->cinfo);
+ p7dcx->cinfo = NULL;
+ }
+ PORT_SetError(p7dcx->error);
+ return SECFailure;
+ }
+
+ return SECSuccess;
+}
+
+SEC_PKCS7ContentInfo *
+SEC_PKCS7DecoderFinish(SEC_PKCS7DecoderContext *p7dcx)
+{
+ SEC_PKCS7ContentInfo *cinfo;
+
+ cinfo = p7dcx->cinfo;
+ if (p7dcx->dcx != NULL) {
+ if (SEC_ASN1DecoderFinish(p7dcx->dcx) != SECSuccess) {
+ SEC_PKCS7DestroyContentInfo(cinfo);
+ cinfo = NULL;
+ }
+ }
+ /* free any NSS data structures */
+ if (p7dcx->worker.decryptobj) {
+ sec_PKCS7DestroyDecryptObject(p7dcx->worker.decryptobj);
+ }
+ PORT_FreeArena(p7dcx->tmp_poolp, PR_FALSE);
+ PORT_Free(p7dcx);
+ return cinfo;
+}
+
+SEC_PKCS7ContentInfo *
+SEC_PKCS7DecodeItem(SECItem *p7item,
+ SEC_PKCS7DecoderContentCallback cb, void *cb_arg,
+ SECKEYGetPasswordKey pwfn, void *pwfn_arg,
+ SEC_PKCS7GetDecryptKeyCallback decrypt_key_cb,
+ void *decrypt_key_cb_arg,
+ SEC_PKCS7DecryptionAllowedCallback decrypt_allowed_cb)
+{
+ SEC_PKCS7DecoderContext *p7dcx;
+
+ p7dcx = SEC_PKCS7DecoderStart(cb, cb_arg, pwfn, pwfn_arg, decrypt_key_cb,
+ decrypt_key_cb_arg, decrypt_allowed_cb);
+ if (!p7dcx) {
+ /* error code is set */
+ return NULL;
+ }
+ (void)SEC_PKCS7DecoderUpdate(p7dcx, (char *)p7item->data, p7item->len);
+ return SEC_PKCS7DecoderFinish(p7dcx);
+}
+
+/*
+ * Abort the ASN.1 stream. Used by pkcs 12
+ */
+void
+SEC_PKCS7DecoderAbort(SEC_PKCS7DecoderContext *p7dcx, int error)
+{
+ PORT_Assert(p7dcx);
+ SEC_ASN1DecoderAbort(p7dcx->dcx, error);
+}
+
+/*
+ * If the thing contains any certs or crls return true; false otherwise.
+ */
+PRBool
+SEC_PKCS7ContainsCertsOrCrls(SEC_PKCS7ContentInfo *cinfo)
+{
+ SECOidTag kind;
+ SECItem **certs;
+ CERTSignedCrl **crls;
+
+ kind = SEC_PKCS7ContentType(cinfo);
+ switch (kind) {
+ default:
+ case SEC_OID_PKCS7_DATA:
+ case SEC_OID_PKCS7_DIGESTED_DATA:
+ case SEC_OID_PKCS7_ENVELOPED_DATA:
+ case SEC_OID_PKCS7_ENCRYPTED_DATA:
+ return PR_FALSE;
+ case SEC_OID_PKCS7_SIGNED_DATA:
+ certs = cinfo->content.signedData->rawCerts;
+ crls = cinfo->content.signedData->crls;
+ break;
+ case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
+ certs = cinfo->content.signedAndEnvelopedData->rawCerts;
+ crls = cinfo->content.signedAndEnvelopedData->crls;
+ break;
+ }
+
+ /*
+ * I know this could be collapsed, but I was in a mood to be explicit.
+ */
+ if (certs != NULL && certs[0] != NULL)
+ return PR_TRUE;
+ else if (crls != NULL && crls[0] != NULL)
+ return PR_TRUE;
+ else
+ return PR_FALSE;
+}
+
+/* return the content length...could use GetContent, however we
+ * need the encrypted content length
+ */
+PRBool
+SEC_PKCS7IsContentEmpty(SEC_PKCS7ContentInfo *cinfo, unsigned int minLen)
+{
+ SECItem *item = NULL;
+
+ if (cinfo == NULL) {
+ return PR_TRUE;
+ }
+
+ switch (SEC_PKCS7ContentType(cinfo)) {
+ case SEC_OID_PKCS7_DATA:
+ item = cinfo->content.data;
+ break;
+ case SEC_OID_PKCS7_ENCRYPTED_DATA:
+ item = &cinfo->content.encryptedData->encContentInfo.encContent;
+ break;
+ default:
+ /* add other types */
+ return PR_FALSE;
+ }
+
+ if (!item) {
+ return PR_TRUE;
+ } else if (item->len <= minLen) {
+ return PR_TRUE;
+ }
+
+ return PR_FALSE;
+}
+
+PRBool
+SEC_PKCS7ContentIsEncrypted(SEC_PKCS7ContentInfo *cinfo)
+{
+ SECOidTag kind;
+
+ kind = SEC_PKCS7ContentType(cinfo);
+ switch (kind) {
+ default:
+ case SEC_OID_PKCS7_DATA:
+ case SEC_OID_PKCS7_DIGESTED_DATA:
+ case SEC_OID_PKCS7_SIGNED_DATA:
+ return PR_FALSE;
+ case SEC_OID_PKCS7_ENCRYPTED_DATA:
+ case SEC_OID_PKCS7_ENVELOPED_DATA:
+ case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
+ return PR_TRUE;
+ }
+}
+
+/*
+ * If the PKCS7 content has a signature (not just *could* have a signature)
+ * return true; false otherwise. This can/should be called before calling
+ * VerifySignature, which will always indicate failure if no signature is
+ * present, but that does not mean there even was a signature!
+ * Note that the content itself can be empty (detached content was sent
+ * another way); it is the presence of the signature that matters.
+ */
+PRBool
+SEC_PKCS7ContentIsSigned(SEC_PKCS7ContentInfo *cinfo)
+{
+ SECOidTag kind;
+ SEC_PKCS7SignerInfo **signerinfos;
+
+ kind = SEC_PKCS7ContentType(cinfo);
+ switch (kind) {
+ default:
+ case SEC_OID_PKCS7_DATA:
+ case SEC_OID_PKCS7_DIGESTED_DATA:
+ case SEC_OID_PKCS7_ENVELOPED_DATA:
+ case SEC_OID_PKCS7_ENCRYPTED_DATA:
+ return PR_FALSE;
+ case SEC_OID_PKCS7_SIGNED_DATA:
+ signerinfos = cinfo->content.signedData->signerInfos;
+ break;
+ case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
+ signerinfos = cinfo->content.signedAndEnvelopedData->signerInfos;
+ break;
+ }
+
+ /*
+ * I know this could be collapsed; but I kind of think it will get
+ * more complicated before I am finished, so...
+ */
+ if (signerinfos != NULL && signerinfos[0] != NULL)
+ return PR_TRUE;
+ else
+ return PR_FALSE;
+}
+
+/*
+ * sec_pkcs7_verify_signature
+ *
+ * Look at a PKCS7 contentInfo and check if the signature is good.
+ * The digest was either calculated earlier (and is stored in the
+ * contentInfo itself) or is passed in via "detached_digest".
+ *
+ * The verification checks that the signing cert is valid and trusted
+ * for the purpose specified by "certusage" at
+ * - "*atTime" if "atTime" is not null, or
+ * - the signing time if the signing time is available in "cinfo", or
+ * - the current time (as returned by PR_Now).
+ *
+ * In addition, if "keepcerts" is true, add any new certificates found
+ * into our local database.
+ *
+ * XXX Each place which returns PR_FALSE should be sure to have a good
+ * error set for inspection by the caller. Alternatively, we could create
+ * an enumeration of success and each type of failure and return that
+ * instead of a boolean. For now, the default in a bad situation is to
+ * set the error to SEC_ERROR_PKCS7_BAD_SIGNATURE. But this should be
+ * reviewed; better (more specific) errors should be possible (to distinguish
+ * a signature failure from a badly-formed pkcs7 signedData, for example).
+ * Some of the errors should probably just be SEC_ERROR_BAD_SIGNATURE,
+ * but that has a less helpful error string associated with it right now;
+ * if/when that changes, review and change these as needed.
+ *
+ * XXX This is broken wrt signedAndEnvelopedData. In that case, the
+ * message digest is doubly encrypted -- first encrypted with the signer
+ * private key but then again encrypted with the bulk encryption key used
+ * to encrypt the content. So before we can pass the digest to VerifyDigest,
+ * we need to decrypt it with the bulk encryption key. Also, in this case,
+ * there should be NO authenticatedAttributes (signerinfo->authAttr should
+ * be NULL).
+ */
+static PRBool
+sec_pkcs7_verify_signature(SEC_PKCS7ContentInfo *cinfo,
+ SECCertUsage certusage,
+ const SECItem *detached_digest,
+ HASH_HashType digest_type,
+ PRBool keepcerts,
+ const PRTime *atTime)
+{
+ SECAlgorithmID **digestalgs, *bulkid;
+ const SECItem *digest;
+ SECItem **digests;
+ SECItem **rawcerts;
+ SEC_PKCS7SignerInfo **signerinfos, *signerinfo;
+ CERTCertificate *cert, **certs;
+ PRBool goodsig;
+ CERTCertDBHandle *certdb, *defaultdb;
+ SECOidTag encTag, digestTag;
+ HASH_HashType found_type;
+ int i, certcount;
+ SECKEYPublicKey *publickey;
+ SECItem *content_type;
+ PK11SymKey *sigkey;
+ SECItem *encoded_stime;
+ PRTime stime;
+ PRTime verificationTime;
+ SECStatus rv;
+
+ /*
+ * Everything needed in order to "goto done" safely.
+ */
+ goodsig = PR_FALSE;
+ certcount = 0;
+ cert = NULL;
+ certs = NULL;
+ certdb = NULL;
+ defaultdb = CERT_GetDefaultCertDB();
+ publickey = NULL;
+
+ if (!SEC_PKCS7ContentIsSigned(cinfo)) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ PORT_Assert(cinfo->contentTypeTag != NULL);
+
+ switch (cinfo->contentTypeTag->offset) {
+ default:
+ case SEC_OID_PKCS7_DATA:
+ case SEC_OID_PKCS7_DIGESTED_DATA:
+ case SEC_OID_PKCS7_ENVELOPED_DATA:
+ case SEC_OID_PKCS7_ENCRYPTED_DATA:
+ /* Could only get here if SEC_PKCS7ContentIsSigned is broken. */
+ PORT_Assert(0);
+ case SEC_OID_PKCS7_SIGNED_DATA: {
+ SEC_PKCS7SignedData *sdp;
+
+ sdp = cinfo->content.signedData;
+ digestalgs = sdp->digestAlgorithms;
+ digests = sdp->digests;
+ rawcerts = sdp->rawCerts;
+ signerinfos = sdp->signerInfos;
+ content_type = &(sdp->contentInfo.contentType);
+ sigkey = NULL;
+ bulkid = NULL;
+ } break;
+ case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA: {
+ SEC_PKCS7SignedAndEnvelopedData *saedp;
+
+ saedp = cinfo->content.signedAndEnvelopedData;
+ digestalgs = saedp->digestAlgorithms;
+ digests = saedp->digests;
+ rawcerts = saedp->rawCerts;
+ signerinfos = saedp->signerInfos;
+ content_type = &(saedp->encContentInfo.contentType);
+ sigkey = saedp->sigKey;
+ bulkid = &(saedp->encContentInfo.contentEncAlg);
+ } break;
+ }
+
+ if ((signerinfos == NULL) || (signerinfos[0] == NULL)) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ /*
+ * XXX Need to handle multiple signatures; checking them is easy,
+ * but what should be the semantics here (like, return value)?
+ */
+ if (signerinfos[1] != NULL) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ signerinfo = signerinfos[0];
+
+ /*
+ * XXX I would like to just pass the issuerAndSN, along with the rawcerts
+ * and crls, to some function that did all of this certificate stuff
+ * (open/close the database if necessary, verifying the certs, etc.)
+ * and gave me back a cert pointer if all was good.
+ */
+ certdb = defaultdb;
+ if (certdb == NULL) {
+ goto done;
+ }
+
+ certcount = 0;
+ if (rawcerts != NULL) {
+ for (; rawcerts[certcount] != NULL; certcount++) {
+ /* just counting */
+ }
+ }
+
+ /*
+ * Note that the result of this is that each cert in "certs"
+ * needs to be destroyed.
+ */
+ rv = CERT_ImportCerts(certdb, certusage, certcount, rawcerts, &certs,
+ keepcerts, PR_FALSE, NULL);
+ if (rv != SECSuccess) {
+ goto done;
+ }
+
+ /*
+ * This cert will also need to be freed, but since we save it
+ * in signerinfo for later, we do not want to destroy it when
+ * we leave this function -- we let the clean-up of the entire
+ * cinfo structure later do the destroy of this cert.
+ */
+ cert = CERT_FindCertByIssuerAndSN(certdb, signerinfo->issuerAndSN);
+ if (cert == NULL) {
+ goto done;
+ }
+
+ signerinfo->cert = cert;
+
+ /*
+ * Get and convert the signing time; if available, it will be used
+ * both on the cert verification and for importing the sender
+ * email profile.
+ */
+ encoded_stime = SEC_PKCS7GetSigningTime(cinfo);
+ if (encoded_stime != NULL) {
+ if (DER_DecodeTimeChoice(&stime, encoded_stime) != SECSuccess)
+ encoded_stime = NULL; /* conversion failed, so pretend none */
+ }
+
+ /*
+ * XXX This uses the signing time, if available. Additionally, we
+ * might want to, if there is no signing time, get the message time
+ * from the mail header itself, and use that. That would require
+ * a change to our interface though, and for S/MIME callers to pass
+ * in a time (and for non-S/MIME callers to pass in nothing, or
+ * maybe make them pass in the current time, always?).
+ */
+ if (atTime) {
+ verificationTime = *atTime;
+ } else if (encoded_stime != NULL) {
+ verificationTime = stime;
+ } else {
+ verificationTime = PR_Now();
+ }
+ if (CERT_VerifyCert(certdb, cert, PR_TRUE, certusage, verificationTime,
+ cinfo->pwfn_arg, NULL) != SECSuccess) {
+ /*
+ * XXX Give the user an option to check the signature anyway?
+ * If we want to do this, need to give a way to leave and display
+ * some dialog and get the answer and come back through (or do
+ * the rest of what we do below elsewhere, maybe by putting it
+ * in a function that we call below and could call from a dialog
+ * finish handler).
+ */
+ goto savecert;
+ }
+
+ publickey = CERT_ExtractPublicKey(cert);
+ if (publickey == NULL)
+ goto done;
+
+ /*
+ * XXX No! If digests is empty, see if we can create it now by
+ * digesting the contents. This is necessary if we want to allow
+ * somebody to do a simple decode (without filtering, etc.) and
+ * then later call us here to do the verification.
+ * OR, we can just specify that the interface to this routine
+ * *requires* that the digest(s) be done before calling and either
+ * stashed in the struct itself or passed in explicitly (as would
+ * be done for detached contents).
+ */
+ if ((digests == NULL || digests[0] == NULL) && (detached_digest == NULL || detached_digest->data == NULL))
+ goto done;
+
+ /*
+ * Find and confirm digest algorithm.
+ */
+ digestTag = SECOID_FindOIDTag(&(signerinfo->digestAlg.algorithm));
+
+ /* make sure we understand the digest type first */
+ found_type = HASH_GetHashTypeByOidTag(digestTag);
+ if ((digestTag == SEC_OID_UNKNOWN) || (found_type == HASH_AlgNULL)) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ if (detached_digest != NULL) {
+ unsigned int hashLen = HASH_ResultLen(found_type);
+
+ if (digest_type != found_type ||
+ detached_digest->len != hashLen) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+ digest = detached_digest;
+ } else {
+ PORT_Assert(digestalgs != NULL && digestalgs[0] != NULL);
+ if (digestalgs == NULL || digestalgs[0] == NULL) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ /*
+ * pick digest matching signerinfo->digestAlg from digests
+ */
+ for (i = 0; digestalgs[i] != NULL; i++) {
+ if (SECOID_FindOIDTag(&(digestalgs[i]->algorithm)) == digestTag)
+ break;
+ }
+ if (digestalgs[i] == NULL) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ digest = digests[i];
+ }
+
+ encTag = SECOID_FindOIDTag(&(signerinfo->digestEncAlg.algorithm));
+ if (encTag == SEC_OID_UNKNOWN) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ if (signerinfo->authAttr != NULL) {
+ SEC_PKCS7Attribute *attr;
+ SECItem *value;
+ SECItem encoded_attrs;
+
+ /*
+ * We have a sigkey only for signedAndEnvelopedData, which is
+ * not supposed to have any authenticated attributes.
+ */
+ if (sigkey != NULL) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ /*
+ * PKCS #7 says that if there are any authenticated attributes,
+ * then there must be one for content type which matches the
+ * content type of the content being signed, and there must
+ * be one for message digest which matches our message digest.
+ * So check these things first.
+ * XXX Might be nice to have a compare-attribute-value function
+ * which could collapse the following nicely.
+ */
+ attr = sec_PKCS7FindAttribute(signerinfo->authAttr,
+ SEC_OID_PKCS9_CONTENT_TYPE, PR_TRUE);
+ value = sec_PKCS7AttributeValue(attr);
+ if (value == NULL || value->len != content_type->len) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+ if (PORT_Memcmp(value->data, content_type->data, value->len) != 0) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ attr = sec_PKCS7FindAttribute(signerinfo->authAttr,
+ SEC_OID_PKCS9_MESSAGE_DIGEST, PR_TRUE);
+ value = sec_PKCS7AttributeValue(attr);
+ if (value == NULL || value->len != digest->len) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+ if (PORT_Memcmp(value->data, digest->data, value->len) != 0) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ /*
+ * Okay, we met the constraints of the basic attributes.
+ * Now check the signature, which is based on a digest of
+ * the DER-encoded authenticated attributes. So, first we
+ * encode and then we digest/verify.
+ */
+ encoded_attrs.data = NULL;
+ encoded_attrs.len = 0;
+ if (sec_PKCS7EncodeAttributes(NULL, &encoded_attrs,
+ &(signerinfo->authAttr)) == NULL)
+ goto done;
+
+ if (encoded_attrs.data == NULL || encoded_attrs.len == 0) {
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ goodsig = (PRBool)(VFY_VerifyDataDirect(encoded_attrs.data,
+ encoded_attrs.len,
+ publickey, &(signerinfo->encDigest),
+ encTag, digestTag, NULL,
+ cinfo->pwfn_arg) == SECSuccess);
+ PORT_Free(encoded_attrs.data);
+ } else {
+ SECItem *sig;
+ SECItem holder;
+
+ /*
+ * No authenticated attributes.
+ * The signature is based on the plain message digest.
+ */
+
+ sig = &(signerinfo->encDigest);
+ if (sig->len == 0) { /* bad signature */
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ goto done;
+ }
+
+ if (sigkey != NULL) {
+ sec_PKCS7CipherObject *decryptobj;
+ unsigned int buflen;
+
+ /*
+ * For signedAndEnvelopedData, we first must decrypt the encrypted
+ * digest with the bulk encryption key. The result is the normal
+ * encrypted digest (aka the signature).
+ */
+ decryptobj = sec_PKCS7CreateDecryptObject(sigkey, bulkid);
+ if (decryptobj == NULL)
+ goto done;
+
+ buflen = sec_PKCS7DecryptLength(decryptobj, sig->len, PR_TRUE);
+ PORT_Assert(buflen);
+ if (buflen == 0) { /* something is wrong */
+ sec_PKCS7DestroyDecryptObject(decryptobj);
+ goto done;
+ }
+
+ holder.data = (unsigned char *)PORT_Alloc(buflen);
+ if (holder.data == NULL) {
+ sec_PKCS7DestroyDecryptObject(decryptobj);
+ goto done;
+ }
+
+ rv = sec_PKCS7Decrypt(decryptobj, holder.data, &holder.len, buflen,
+ sig->data, sig->len, PR_TRUE);
+ sec_PKCS7DestroyDecryptObject(decryptobj);
+ if (rv != SECSuccess) {
+ goto done;
+ }
+
+ sig = &holder;
+ }
+
+ goodsig = (PRBool)(VFY_VerifyDigestDirect(digest, publickey, sig,
+ encTag, digestTag, cinfo->pwfn_arg) == SECSuccess);
+
+ if (sigkey != NULL) {
+ PORT_Assert(sig == &holder);
+ PORT_ZFree(holder.data, holder.len);
+ }
+ }
+
+ if (!goodsig) {
+ /*
+ * XXX Change the generic error into our specific one, because
+ * in that case we get a better explanation out of the Security
+ * Advisor. This is really a bug in our error strings (the
+ * "generic" error has a lousy/wrong message associated with it
+ * which assumes the signature verification was done for the
+ * purposes of checking the issuer signature on a certificate)
+ * but this is at least an easy workaround and/or in the
+ * Security Advisor, which specifically checks for the error
+ * SEC_ERROR_PKCS7_BAD_SIGNATURE and gives more explanation
+ * in that case but does not similarly check for
+ * SEC_ERROR_BAD_SIGNATURE. It probably should, but then would
+ * probably say the wrong thing in the case that it *was* the
+ * certificate signature check that failed during the cert
+ * verification done above. Our error handling is really a mess.
+ */
+ if (PORT_GetError() == SEC_ERROR_BAD_SIGNATURE)
+ PORT_SetError(SEC_ERROR_PKCS7_BAD_SIGNATURE);
+ }
+
+savecert:
+ /*
+ * Only save the smime profile if we are checking an email message and
+ * the cert has an email address in it.
+ */
+ if (cert->emailAddr && cert->emailAddr[0] &&
+ ((certusage == certUsageEmailSigner) ||
+ (certusage == certUsageEmailRecipient))) {
+ SECItem *profile = NULL;
+ int save_error;
+
+ /*
+ * Remember the current error set because we do not care about
+ * anything set by the functions we are about to call.
+ */
+ save_error = PORT_GetError();
+
+ if (goodsig && (signerinfo->authAttr != NULL)) {
+ /*
+ * If the signature is good, then we can save the S/MIME profile,
+ * if we have one.
+ */
+ SEC_PKCS7Attribute *attr;
+
+ attr = sec_PKCS7FindAttribute(signerinfo->authAttr,
+ SEC_OID_PKCS9_SMIME_CAPABILITIES,
+ PR_TRUE);
+ profile = sec_PKCS7AttributeValue(attr);
+ }
+
+ rv = CERT_SaveSMimeProfile(cert, profile, encoded_stime);
+
+ /*
+ * Restore the saved error in case the calls above set a new
+ * one that we do not actually care about.
+ */
+ PORT_SetError(save_error);
+
+ /*
+ * XXX Failure is not indicated anywhere -- the signature
+ * verification itself is unaffected by whether or not the
+ * profile was successfully saved.
+ */
+ }
+
+done:
+
+ /*
+ * See comment above about why we do not want to destroy cert
+ * itself here.
+ */
+
+ if (certs != NULL)
+ CERT_DestroyCertArray(certs, certcount);
+
+ if (publickey != NULL)
+ SECKEY_DestroyPublicKey(publickey);
+
+ return goodsig;
+}
+
+/*
+ * SEC_PKCS7VerifySignature
+ * Look at a PKCS7 contentInfo and check if the signature is good.
+ * The verification checks that the signing cert is valid and trusted
+ * for the purpose specified by "certusage".
+ *
+ * In addition, if "keepcerts" is true, add any new certificates found
+ * into our local database.
+ */
+PRBool
+SEC_PKCS7VerifySignature(SEC_PKCS7ContentInfo *cinfo,
+ SECCertUsage certusage,
+ PRBool keepcerts)
+{
+ return sec_pkcs7_verify_signature(cinfo, certusage,
+ NULL, HASH_AlgNULL, keepcerts, NULL);
+}
+
+/*
+ * SEC_PKCS7VerifyDetachedSignature
+ * Look at a PKCS7 contentInfo and check if the signature matches
+ * a passed-in digest (calculated, supposedly, from detached contents).
+ * The verification checks that the signing cert is valid and trusted
+ * for the purpose specified by "certusage".
+ *
+ * In addition, if "keepcerts" is true, add any new certificates found
+ * into our local database.
+ */
+PRBool
+SEC_PKCS7VerifyDetachedSignature(SEC_PKCS7ContentInfo *cinfo,
+ SECCertUsage certusage,
+ const SECItem *detached_digest,
+ HASH_HashType digest_type,
+ PRBool keepcerts)
+{
+ return sec_pkcs7_verify_signature(cinfo, certusage,
+ detached_digest, digest_type,
+ keepcerts, NULL);
+}
+
+/*
+ * SEC_PKCS7VerifyDetachedSignatureAtTime
+ * Look at a PKCS7 contentInfo and check if the signature matches
+ * a passed-in digest (calculated, supposedly, from detached contents).
+ * The verification checks that the signing cert is valid and trusted
+ * for the purpose specified by "certusage" at time "atTime".
+ *
+ * In addition, if "keepcerts" is true, add any new certificates found
+ * into our local database.
+ */
+PRBool
+SEC_PKCS7VerifyDetachedSignatureAtTime(SEC_PKCS7ContentInfo *cinfo,
+ SECCertUsage certusage,
+ const SECItem *detached_digest,
+ HASH_HashType digest_type,
+ PRBool keepcerts,
+ PRTime atTime)
+{
+ return sec_pkcs7_verify_signature(cinfo, certusage,
+ detached_digest, digest_type,
+ keepcerts, &atTime);
+}
+
+/*
+ * Return the asked-for portion of the name of the signer of a PKCS7
+ * signed object.
+ *
+ * Returns a pointer to allocated memory, which must be freed.
+ * A NULL return value is an error.
+ */
+
+#define sec_common_name 1
+#define sec_email_address 2
+
+static char *
+sec_pkcs7_get_signer_cert_info(SEC_PKCS7ContentInfo *cinfo, int selector)
+{
+ SECOidTag kind;
+ SEC_PKCS7SignerInfo **signerinfos;
+ CERTCertificate *signercert;
+ char *container;
+
+ kind = SEC_PKCS7ContentType(cinfo);
+ switch (kind) {
+ default:
+ case SEC_OID_PKCS7_DATA:
+ case SEC_OID_PKCS7_DIGESTED_DATA:
+ case SEC_OID_PKCS7_ENVELOPED_DATA:
+ case SEC_OID_PKCS7_ENCRYPTED_DATA:
+ PORT_Assert(0);
+ return NULL;
+ case SEC_OID_PKCS7_SIGNED_DATA: {
+ SEC_PKCS7SignedData *sdp;
+
+ sdp = cinfo->content.signedData;
+ signerinfos = sdp->signerInfos;
+ } break;
+ case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA: {
+ SEC_PKCS7SignedAndEnvelopedData *saedp;
+
+ saedp = cinfo->content.signedAndEnvelopedData;
+ signerinfos = saedp->signerInfos;
+ } break;
+ }
+
+ if (signerinfos == NULL || signerinfos[0] == NULL)
+ return NULL;
+
+ signercert = signerinfos[0]->cert;
+
+ /*
+ * No cert there; see if we can find one by calling verify ourselves.
+ */
+ if (signercert == NULL) {
+ /*
+ * The cert usage does not matter in this case, because we do not
+ * actually care about the verification itself, but we have to pick
+ * some valid usage to pass in.
+ */
+ (void)sec_pkcs7_verify_signature(cinfo, certUsageEmailSigner,
+ NULL, HASH_AlgNULL, PR_FALSE, NULL);
+ signercert = signerinfos[0]->cert;
+ if (signercert == NULL)
+ return NULL;
+ }
+
+ switch (selector) {
+ case sec_common_name:
+ container = CERT_GetCommonName(&signercert->subject);
+ break;
+ case sec_email_address:
+ if (signercert->emailAddr && signercert->emailAddr[0]) {
+ container = PORT_Strdup(signercert->emailAddr);
+ } else {
+ container = NULL;
+ }
+ break;
+ default:
+ PORT_Assert(0);
+ container = NULL;
+ break;
+ }
+
+ return container;
+}
+
+char *
+SEC_PKCS7GetSignerCommonName(SEC_PKCS7ContentInfo *cinfo)
+{
+ return sec_pkcs7_get_signer_cert_info(cinfo, sec_common_name);
+}
+
+char *
+SEC_PKCS7GetSignerEmailAddress(SEC_PKCS7ContentInfo *cinfo)
+{
+ return sec_pkcs7_get_signer_cert_info(cinfo, sec_email_address);
+}
+
+/*
+ * Return the signing time, in UTCTime format, of a PKCS7 contentInfo.
+ */
+SECItem *
+SEC_PKCS7GetSigningTime(SEC_PKCS7ContentInfo *cinfo)
+{
+ SEC_PKCS7SignerInfo **signerinfos;
+ SEC_PKCS7Attribute *attr;
+
+ if (SEC_PKCS7ContentType(cinfo) != SEC_OID_PKCS7_SIGNED_DATA)
+ return NULL;
+
+ signerinfos = cinfo->content.signedData->signerInfos;
+
+ /*
+ * No signature, or more than one, means no deal.
+ */
+ if (signerinfos == NULL || signerinfos[0] == NULL || signerinfos[1] != NULL)
+ return NULL;
+
+ attr = sec_PKCS7FindAttribute(signerinfos[0]->authAttr,
+ SEC_OID_PKCS9_SIGNING_TIME, PR_TRUE);
+ return sec_PKCS7AttributeValue(attr);
+}