1 files changed, 396 insertions, 0 deletions

diff --git a/src/lib/libcrypto/ct/ct_sct.c b/src/lib/libcrypto/ct/ct_sct.c
new file mode 100644
index 0000000000..4ff36e2fbd
--- /dev/null
+++ b/src/lib/libcrypto/ct/ct_sct.c
@@ -0,0 +1,396 @@
+/*
+ * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#ifdef OPENSSL_NO_CT
+# error "CT disabled"
+#endif
+
+#include <openssl/ct.h>
+#include <openssl/err.h>
+#include <openssl/evp.h>
+#include <openssl/tls1.h>
+#include <openssl/x509.h>
+
+#include "ct_local.h"
+
+SCT *SCT_new(void)
+{
+    SCT *sct = OPENSSL_zalloc(sizeof(*sct));
+
+    if (sct == NULL) {
+        CTerr(CT_F_SCT_NEW, ERR_R_MALLOC_FAILURE);
+        return NULL;
+    }
+
+    sct->entry_type = CT_LOG_ENTRY_TYPE_NOT_SET;
+    sct->version = SCT_VERSION_NOT_SET;
+    return sct;
+}
+
+void SCT_free(SCT *sct)
+{
+    if (sct == NULL)
+        return;
+
+    OPENSSL_free(sct->log_id);
+    OPENSSL_free(sct->ext);
+    OPENSSL_free(sct->sig);
+    OPENSSL_free(sct->sct);
+    OPENSSL_free(sct);
+}
+
+void SCT_LIST_free(STACK_OF(SCT) *a)
+{
+    sk_SCT_pop_free(a, SCT_free);
+}
+
+int SCT_set_version(SCT *sct, sct_version_t version)
+{
+    if (version != SCT_VERSION_V1) {
+        CTerr(CT_F_SCT_SET_VERSION, CT_R_UNSUPPORTED_VERSION);
+        return 0;
+    }
+    sct->version = version;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+    return 1;
+}
+
+int SCT_set_log_entry_type(SCT *sct, ct_log_entry_type_t entry_type)
+{
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+
+    switch (entry_type) {
+    case CT_LOG_ENTRY_TYPE_X509:
+    case CT_LOG_ENTRY_TYPE_PRECERT:
+        sct->entry_type = entry_type;
+        return 1;
+    case CT_LOG_ENTRY_TYPE_NOT_SET:
+        break;
+    }
+    CTerr(CT_F_SCT_SET_LOG_ENTRY_TYPE, CT_R_UNSUPPORTED_ENTRY_TYPE);
+    return 0;
+}
+
+int SCT_set0_log_id(SCT *sct, unsigned char *log_id, size_t log_id_len)
+{
+    if (sct->version == SCT_VERSION_V1 && log_id_len != CT_V1_HASHLEN) {
+        CTerr(CT_F_SCT_SET0_LOG_ID, CT_R_INVALID_LOG_ID_LENGTH);
+        return 0;
+    }
+
+    OPENSSL_free(sct->log_id);
+    sct->log_id = log_id;
+    sct->log_id_len = log_id_len;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+    return 1;
+}
+
+int SCT_set1_log_id(SCT *sct, const unsigned char *log_id, size_t log_id_len)
+{
+    if (sct->version == SCT_VERSION_V1 && log_id_len != CT_V1_HASHLEN) {
+        CTerr(CT_F_SCT_SET1_LOG_ID, CT_R_INVALID_LOG_ID_LENGTH);
+        return 0;
+    }
+
+    OPENSSL_free(sct->log_id);
+    sct->log_id = NULL;
+    sct->log_id_len = 0;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+
+    if (log_id != NULL && log_id_len > 0) {
+        sct->log_id = OPENSSL_memdup(log_id, log_id_len);
+        if (sct->log_id == NULL) {
+            CTerr(CT_F_SCT_SET1_LOG_ID, ERR_R_MALLOC_FAILURE);
+            return 0;
+        }
+        sct->log_id_len = log_id_len;
+    }
+    return 1;
+}
+
+
+void SCT_set_timestamp(SCT *sct, uint64_t timestamp)
+{
+    sct->timestamp = timestamp;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+}
+
+int SCT_set_signature_nid(SCT *sct, int nid)
+{
+    switch (nid) {
+    case NID_sha256WithRSAEncryption:
+        sct->hash_alg = TLSEXT_hash_sha256;
+        sct->sig_alg = TLSEXT_signature_rsa;
+        sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+        return 1;
+    case NID_ecdsa_with_SHA256:
+        sct->hash_alg = TLSEXT_hash_sha256;
+        sct->sig_alg = TLSEXT_signature_ecdsa;
+        sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+        return 1;
+    default:
+        CTerr(CT_F_SCT_SET_SIGNATURE_NID, CT_R_UNRECOGNIZED_SIGNATURE_NID);
+        return 0;
+    }
+}
+
+void SCT_set0_extensions(SCT *sct, unsigned char *ext, size_t ext_len)
+{
+    OPENSSL_free(sct->ext);
+    sct->ext = ext;
+    sct->ext_len = ext_len;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+}
+
+int SCT_set1_extensions(SCT *sct, const unsigned char *ext, size_t ext_len)
+{
+    OPENSSL_free(sct->ext);
+    sct->ext = NULL;
+    sct->ext_len = 0;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+
+    if (ext != NULL && ext_len > 0) {
+        sct->ext = OPENSSL_memdup(ext, ext_len);
+        if (sct->ext == NULL) {
+            CTerr(CT_F_SCT_SET1_EXTENSIONS, ERR_R_MALLOC_FAILURE);
+            return 0;
+        }
+        sct->ext_len = ext_len;
+    }
+    return 1;
+}
+
+void SCT_set0_signature(SCT *sct, unsigned char *sig, size_t sig_len)
+{
+    OPENSSL_free(sct->sig);
+    sct->sig = sig;
+    sct->sig_len = sig_len;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+}
+
+int SCT_set1_signature(SCT *sct, const unsigned char *sig, size_t sig_len)
+{
+    OPENSSL_free(sct->sig);
+    sct->sig = NULL;
+    sct->sig_len = 0;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+
+    if (sig != NULL && sig_len > 0) {
+        sct->sig = OPENSSL_memdup(sig, sig_len);
+        if (sct->sig == NULL) {
+            CTerr(CT_F_SCT_SET1_SIGNATURE, ERR_R_MALLOC_FAILURE);
+            return 0;
+        }
+        sct->sig_len = sig_len;
+    }
+    return 1;
+}
+
+sct_version_t SCT_get_version(const SCT *sct)
+{
+    return sct->version;
+}
+
+ct_log_entry_type_t SCT_get_log_entry_type(const SCT *sct)
+{
+    return sct->entry_type;
+}
+
+size_t SCT_get0_log_id(const SCT *sct, unsigned char **log_id)
+{
+    *log_id = sct->log_id;
+    return sct->log_id_len;
+}
+
+uint64_t SCT_get_timestamp(const SCT *sct)
+{
+    return sct->timestamp;
+}
+
+int SCT_get_signature_nid(const SCT *sct)
+{
+    if (sct->version == SCT_VERSION_V1) {
+        if (sct->hash_alg == TLSEXT_hash_sha256) {
+            switch (sct->sig_alg) {
+            case TLSEXT_signature_ecdsa:
+                return NID_ecdsa_with_SHA256;
+            case TLSEXT_signature_rsa:
+                return NID_sha256WithRSAEncryption;
+            default:
+                return NID_undef;
+            }
+        }
+    }
+    return NID_undef;
+}
+
+size_t SCT_get0_extensions(const SCT *sct, unsigned char **ext)
+{
+    *ext = sct->ext;
+    return sct->ext_len;
+}
+
+size_t SCT_get0_signature(const SCT *sct, unsigned char **sig)
+{
+    *sig = sct->sig;
+    return sct->sig_len;
+}
+
+int SCT_is_complete(const SCT *sct)
+{
+    switch (sct->version) {
+    case SCT_VERSION_NOT_SET:
+        return 0;
+    case SCT_VERSION_V1:
+        return sct->log_id != NULL && SCT_signature_is_complete(sct);
+    default:
+        return sct->sct != NULL; /* Just need cached encoding */
+    }
+}
+
+int SCT_signature_is_complete(const SCT *sct)
+{
+    return SCT_get_signature_nid(sct) != NID_undef &&
+        sct->sig != NULL && sct->sig_len > 0;
+}
+
+sct_source_t SCT_get_source(const SCT *sct)
+{
+    return sct->source;
+}
+
+int SCT_set_source(SCT *sct, sct_source_t source)
+{
+    sct->source = source;
+    sct->validation_status = SCT_VALIDATION_STATUS_NOT_SET;
+    switch (source) {
+    case SCT_SOURCE_TLS_EXTENSION:
+    case SCT_SOURCE_OCSP_STAPLED_RESPONSE:
+        return SCT_set_log_entry_type(sct, CT_LOG_ENTRY_TYPE_X509);
+    case SCT_SOURCE_X509V3_EXTENSION:
+        return SCT_set_log_entry_type(sct, CT_LOG_ENTRY_TYPE_PRECERT);
+    case SCT_SOURCE_UNKNOWN:
+        break;
+    }
+    /* if we aren't sure, leave the log entry type alone */
+    return 1;
+}
+
+sct_validation_status_t SCT_get_validation_status(const SCT *sct)
+{
+    return sct->validation_status;
+}
+
+int SCT_validate(SCT *sct, const CT_POLICY_EVAL_CTX *ctx)
+{
+    int is_sct_valid = -1;
+    SCT_CTX *sctx = NULL;
+    X509_PUBKEY *pub = NULL, *log_pkey = NULL;
+    const CTLOG *log;
+
+    /*
+     * With an unrecognized SCT version we don't know what such an SCT means,
+     * let alone validate one.  So we return validation failure (0).
+     */
+    if (sct->version != SCT_VERSION_V1) {
+        sct->validation_status = SCT_VALIDATION_STATUS_UNKNOWN_VERSION;
+        return 0;
+    }
+
+    log = CTLOG_STORE_get0_log_by_id(ctx->log_store,
+                                     sct->log_id, sct->log_id_len);
+
+    /* Similarly, an SCT from an unknown log also cannot be validated. */
+    if (log == NULL) {
+        sct->validation_status = SCT_VALIDATION_STATUS_UNKNOWN_LOG;
+        return 0;
+    }
+
+    sctx = SCT_CTX_new();
+    if (sctx == NULL)
+        goto err;
+
+    if (X509_PUBKEY_set(&log_pkey, CTLOG_get0_public_key(log)) != 1)
+        goto err;
+    if (SCT_CTX_set1_pubkey(sctx, log_pkey) != 1)
+        goto err;
+
+    if (SCT_get_log_entry_type(sct) == CT_LOG_ENTRY_TYPE_PRECERT) {
+        EVP_PKEY *issuer_pkey;
+
+        if (ctx->issuer == NULL) {
+            sct->validation_status = SCT_VALIDATION_STATUS_UNVERIFIED;
+            goto end;
+        }
+
+        issuer_pkey = X509_get0_pubkey(ctx->issuer);
+
+        if (X509_PUBKEY_set(&pub, issuer_pkey) != 1)
+            goto err;
+        if (SCT_CTX_set1_issuer_pubkey(sctx, pub) != 1)
+            goto err;
+    }
+
+    SCT_CTX_set_time(sctx, ctx->epoch_time_in_ms);
+
+    /*
+     * XXX: Potential for optimization.  This repeats some idempotent heavy
+     * lifting on the certificate for each candidate SCT, and appears to not
+     * use any information in the SCT itself, only the certificate is
+     * processed.  So it may make more sense to to do this just once, perhaps
+     * associated with the shared (by all SCTs) policy eval ctx.
+     *
+     * XXX: Failure here is global (SCT independent) and represents either an
+     * issue with the certificate (e.g. duplicate extensions) or an out of
+     * memory condition.  When the certificate is incompatible with CT, we just
+     * mark the SCTs invalid, rather than report a failure to determine the
+     * validation status.  That way, callbacks that want to do "soft" SCT
+     * processing will not abort handshakes with false positive internal
+     * errors.  Since the function does not distinguish between certificate
+     * issues (peer's fault) and internal problems (out fault) the safe thing
+     * to do is to report a validation failure and let the callback or
+     * application decide what to do.
+     */
+    if (SCT_CTX_set1_cert(sctx, ctx->cert, NULL) != 1)
+        sct->validation_status = SCT_VALIDATION_STATUS_UNVERIFIED;
+    else
+        sct->validation_status = SCT_CTX_verify(sctx, sct) == 1 ?
+            SCT_VALIDATION_STATUS_VALID : SCT_VALIDATION_STATUS_INVALID;
+
+end:
+    is_sct_valid = sct->validation_status == SCT_VALIDATION_STATUS_VALID;
+err:
+    X509_PUBKEY_free(pub);
+    X509_PUBKEY_free(log_pkey);
+    SCT_CTX_free(sctx);
+
+    return is_sct_valid;
+}
+
+int SCT_LIST_validate(const STACK_OF(SCT) *scts, CT_POLICY_EVAL_CTX *ctx)
+{
+    int are_scts_valid = 1;
+    int sct_count = scts != NULL ? sk_SCT_num(scts) : 0;
+    int i;
+
+    for (i = 0; i < sct_count; ++i) {
+        int is_sct_valid = -1;
+        SCT *sct = sk_SCT_value(scts, i);
+
+        if (sct == NULL)
+            continue;
+
+        is_sct_valid = SCT_validate(sct, ctx);
+        if (is_sct_valid < 0)
+            return is_sct_valid;
+        are_scts_valid &= is_sct_valid;
+    }
+
+    return are_scts_valid;
+}