Commit a99be006 authored by Rob Percival's avatar Rob Percival Committed by Rich Salz
Browse files

Check that SCT timestamps are not in the future 



Reviewed-by: default avatarViktor Dukhovni <viktor@openssl.org>
Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1554)
(cherry picked from commit 1fa9ffd9)
parent 5be6f718

crypto/ct/ct_err.c

+2 −1
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ static ERR_STRING_DATA CT_str_functs[] = { 
    {ERR_FUNC(CT_F_O2I_SCT_LIST), "o2i_SCT_LIST"},

    {ERR_FUNC(CT_F_O2I_SCT_SIGNATURE), "o2i_SCT_signature"},

    {ERR_FUNC(CT_F_SCT_CTX_NEW), "SCT_CTX_new"},

    {ERR_FUNC(CT_F_SCT_CTX_VERIFY), "SCT_CTX_verify"},

    {ERR_FUNC(CT_F_SCT_NEW), "SCT_new"},

    {ERR_FUNC(CT_F_SCT_NEW_FROM_BASE64), "SCT_new_from_base64"},

    {ERR_FUNC(CT_F_SCT_SET0_LOG_ID), "SCT_set0_log_id"},
@@ -45,7 +46,6 @@ static ERR_STRING_DATA CT_str_functs[] = { 
    {ERR_FUNC(CT_F_SCT_SET_LOG_ENTRY_TYPE), "SCT_set_log_entry_type"},

    {ERR_FUNC(CT_F_SCT_SET_SIGNATURE_NID), "SCT_set_signature_nid"},

    {ERR_FUNC(CT_F_SCT_SET_VERSION), "SCT_set_version"},

    {ERR_FUNC(CT_F_SCT_CTX_VERIFY), "SCT_CTX_verify"},

    {0, NULL}

};
@@ -58,6 +58,7 @@ static ERR_STRING_DATA CT_str_reasons[] = { 
     "log conf missing description"},

    {ERR_REASON(CT_R_LOG_CONF_MISSING_KEY), "log conf missing key"},

    {ERR_REASON(CT_R_LOG_KEY_INVALID), "log key invalid"},

    {ERR_REASON(CT_R_SCT_FUTURE_TIMESTAMP), "sct future timestamp"},

    {ERR_REASON(CT_R_SCT_INVALID), "sct invalid"},

    {ERR_REASON(CT_R_SCT_INVALID_SIGNATURE), "sct invalid signature"},

    {ERR_REASON(CT_R_SCT_LIST_INVALID), "sct list invalid"},

crypto/ct/ct_locl.h

+12 −0
Original line number Diff line number Diff line
@@ -98,6 +98,8 @@ struct sct_ctx_st { 
    /* pre-certificate encoding */

    unsigned char *preder;

    size_t prederlen;

    /* milliseconds since epoch (to check that the SCT isn't from the future) */

    uint64_t epoch_time_in_ms;

};



/* Context when evaluating whether a Certificate Transparency policy is met */
@@ -105,6 +107,8 @@ struct ct_policy_eval_ctx_st { 
    X509 *cert;

    X509 *issuer;

    CTLOG_STORE *log_store;

    /* milliseconds since epoch (to check that SCTs aren't from the future) */

    uint64_t epoch_time_in_ms;

};



/*
@@ -150,6 +154,14 @@ __owur int SCT_CTX_set1_issuer_pubkey(SCT_CTX *sctx, X509_PUBKEY *pubkey); 
 */

__owur int SCT_CTX_set1_pubkey(SCT_CTX *sctx, X509_PUBKEY *pubkey);



/*

 * Sets the current time, in milliseconds since the Unix epoch.

 * The timestamp of the SCT will be compared to this, to check that it was not

 * issued in the future. RFC6962 states that "TLS clients MUST reject SCTs whose

 * timestamp is in the future", so SCT verification will fail in this case.

 */

void SCT_CTX_set_time(SCT_CTX *sctx, uint64_t time_in_ms);



/*

 * Verifies an SCT with the given context.

 * Returns 1 if the SCT verifies successfully; any other value indicates

crypto/ct/ct_policy.c

+9 −0
Original line number Diff line number Diff line
@@ -59,6 +59,11 @@ void CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE(CT_POLICY_EVAL_CTX *ctx, 
    ctx->log_store = log_store;

}



void CT_POLICY_EVAL_CTX_set_time(CT_POLICY_EVAL_CTX *ctx, uint64_t time_in_ms)

{

    ctx->epoch_time_in_ms = time_in_ms;

}



X509* CT_POLICY_EVAL_CTX_get0_cert(const CT_POLICY_EVAL_CTX *ctx)

{

    return ctx->cert;
@@ -74,3 +79,7 @@ const CTLOG_STORE *CT_POLICY_EVAL_CTX_get0_log_store(const CT_POLICY_EVAL_CTX *c 
    return ctx->log_store;

}



uint64_t CT_POLICY_EVAL_CTX_get_time(const CT_POLICY_EVAL_CTX *ctx)

{

    return ctx->epoch_time_in_ms;

}

crypto/ct/ct_sct.c

+2 −0
Original line number Diff line number Diff line
@@ -329,6 +329,8 @@ int SCT_validate(SCT *sct, const CT_POLICY_EVAL_CTX *ctx) 
            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

crypto/ct/ct_sct_ctx.c

+5 −0
Original line number Diff line number Diff line
@@ -256,3 +256,8 @@ int SCT_CTX_set1_pubkey(SCT_CTX *sctx, X509_PUBKEY *pubkey) 
    sctx->pkey = pkey;

    return 1;

}



void SCT_CTX_set_time(SCT_CTX *sctx, uint64_t time_in_ms)

{

    sctx->epoch_time_in_ms = time_in_ms;

}