diff options
Diffstat (limited to 'crypto/asymmetric_keys/pkcs7_parser.c')
| -rw-r--r-- | crypto/asymmetric_keys/pkcs7_parser.c | 138 |
1 files changed, 132 insertions, 6 deletions
diff --git a/crypto/asymmetric_keys/pkcs7_parser.c b/crypto/asymmetric_keys/pkcs7_parser.c index 826e2f3f507b..e6298b7a945a 100644 --- a/crypto/asymmetric_keys/pkcs7_parser.c +++ b/crypto/asymmetric_keys/pkcs7_parser.c @@ -81,6 +81,30 @@ void pkcs7_free_message(struct pkcs7_message *pkcs7) } EXPORT_SYMBOL_GPL(pkcs7_free_message); +/* + * Check authenticatedAttributes are provided or not provided consistently. + */ +static int pkcs7_check_authattrs(struct pkcs7_message *msg) +{ + struct pkcs7_signed_info *sinfo; + bool want; + + sinfo = msg->signed_infos; + if (sinfo->authattrs) { + want = true; + msg->have_authattrs = true; + } + + for (sinfo = sinfo->next; sinfo; sinfo = sinfo->next) + if (!!sinfo->authattrs != want) + goto inconsistent; + return 0; + +inconsistent: + pr_warn("Inconsistently supplied authAttrs\n"); + return -EINVAL; +} + /** * pkcs7_parse_message - Parse a PKCS#7 message * @data: The raw binary ASN.1 encoded message to be parsed @@ -113,6 +137,10 @@ struct pkcs7_message *pkcs7_parse_message(const void *data, size_t datalen) goto out; } + ret = pkcs7_check_authattrs(ctx->msg); + if (ret < 0) + goto out; + msg = ctx->msg; ctx->msg = NULL; @@ -381,6 +409,25 @@ int pkcs7_note_certificate_list(void *context, size_t hdrlen, } /* + * Note the content type. + */ +int pkcs7_note_content(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + if (ctx->last_oid != OID_data && + ctx->last_oid != OID_msIndirectData) { + pr_warn("Unsupported data type %d\n", ctx->last_oid); + return -EINVAL; + } + + ctx->msg->data_type = ctx->last_oid; + return 0; +} + +/* * Extract the data from the message and store that and its content type OID in * the context. */ @@ -395,31 +442,90 @@ int pkcs7_note_data(void *context, size_t hdrlen, ctx->msg->data = value; ctx->msg->data_len = vlen; ctx->msg->data_hdrlen = hdrlen; - ctx->msg->data_type = ctx->last_oid; return 0; } /* - * Parse authenticated attributes + * Parse authenticated attributes. */ int pkcs7_sig_note_authenticated_attr(void *context, size_t hdrlen, unsigned char tag, const void *value, size_t vlen) { struct pkcs7_parse_context *ctx = context; + struct pkcs7_signed_info *sinfo = ctx->sinfo; + enum OID content_type; pr_devel("AuthAttr: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value); switch (ctx->last_oid) { + case OID_contentType: + if (__test_and_set_bit(sinfo_has_content_type, &sinfo->aa_set)) + goto repeated; + content_type = look_up_OID(value, vlen); + if (content_type != ctx->msg->data_type) { + pr_warn("Mismatch between global data type (%d) and sinfo %u (%d)\n", + ctx->msg->data_type, sinfo->index, + content_type); + return -EBADMSG; + } + return 0; + + case OID_signingTime: + if (__test_and_set_bit(sinfo_has_signing_time, &sinfo->aa_set)) + goto repeated; + /* Should we check that the signing time is consistent + * with the signer's X.509 cert? + */ + return x509_decode_time(&sinfo->signing_time, + hdrlen, tag, value, vlen); + case OID_messageDigest: + if (__test_and_set_bit(sinfo_has_message_digest, &sinfo->aa_set)) + goto repeated; if (tag != ASN1_OTS) return -EBADMSG; - ctx->sinfo->msgdigest = value; - ctx->sinfo->msgdigest_len = vlen; + sinfo->msgdigest = value; + sinfo->msgdigest_len = vlen; + return 0; + + case OID_smimeCapabilites: + if (__test_and_set_bit(sinfo_has_smime_caps, &sinfo->aa_set)) + goto repeated; + if (ctx->msg->data_type != OID_msIndirectData) { + pr_warn("S/MIME Caps only allowed with Authenticode\n"); + return -EKEYREJECTED; + } + return 0; + + /* Microsoft SpOpusInfo seems to be contain cont[0] 16-bit BE + * char URLs and cont[1] 8-bit char URLs. + * + * Microsoft StatementType seems to contain a list of OIDs that + * are also used as extendedKeyUsage types in X.509 certs. + */ + case OID_msSpOpusInfo: + if (__test_and_set_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) + goto repeated; + goto authenticode_check; + case OID_msStatementType: + if (__test_and_set_bit(sinfo_has_ms_statement_type, &sinfo->aa_set)) + goto repeated; + authenticode_check: + if (ctx->msg->data_type != OID_msIndirectData) { + pr_warn("Authenticode AuthAttrs only allowed with Authenticode\n"); + return -EKEYREJECTED; + } + /* I'm not sure how to validate these */ return 0; default: return 0; } + +repeated: + /* We permit max one item per AuthenticatedAttribute and no repeats */ + pr_warn("Repeated/multivalue AuthAttrs not permitted\n"); + return -EKEYREJECTED; } /* @@ -430,10 +536,25 @@ int pkcs7_sig_note_set_of_authattrs(void *context, size_t hdrlen, const void *value, size_t vlen) { struct pkcs7_parse_context *ctx = context; + struct pkcs7_signed_info *sinfo = ctx->sinfo; + + if (!test_bit(sinfo_has_content_type, &sinfo->aa_set) || + !test_bit(sinfo_has_message_digest, &sinfo->aa_set) || + (ctx->msg->data_type == OID_msIndirectData && + !test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set))) { + pr_warn("Missing required AuthAttr\n"); + return -EBADMSG; + } + + if (ctx->msg->data_type != OID_msIndirectData && + test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) { + pr_warn("Unexpected Authenticode AuthAttr\n"); + return -EBADMSG; + } /* We need to switch the 'CONT 0' to a 'SET OF' when we digest */ - ctx->sinfo->authattrs = value - (hdrlen - 1); - ctx->sinfo->authattrs_len = vlen + (hdrlen - 1); + sinfo->authattrs = value - (hdrlen - 1); + sinfo->authattrs_len = vlen + (hdrlen - 1); return 0; } @@ -511,6 +632,11 @@ int pkcs7_note_signed_info(void *context, size_t hdrlen, struct pkcs7_signed_info *sinfo = ctx->sinfo; struct asymmetric_key_id *kid; + if (ctx->msg->data_type == OID_msIndirectData && !sinfo->authattrs) { + pr_warn("Authenticode requires AuthAttrs\n"); + return -EBADMSG; + } + /* Generate cert issuer + serial number key ID */ if (!ctx->expect_skid) { kid = asymmetric_key_generate_id(ctx->raw_serial, |