Commit 18b3a80a authored by Matt Caswell's avatar Matt Caswell
Browse files

Fix crash in tls13_enc 



If s->s3->tmp.new_cipher is NULL then a crash can occur. This can happen
if an alert gets sent after version negotiation (i.e. we have selected
TLSv1.3 and ended up in tls13_enc), but before a ciphersuite has been
selected.

Reviewed-by: default avatarRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2575)
parent 21d94d44

ssl/record/ssl3_record_tls13.c

+12 −1
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
 * https://www.openssl.org/source/license.html

 */



#include <assert.h>

#include "../ssl_locl.h"

#include "record_locl.h"
@@ -29,7 +30,7 @@ int tls13_enc(SSL *s, SSL3_RECORD *recs, size_t n_recs, int send) 
    unsigned char *seq;

    int lenu, lenf;

    SSL3_RECORD *rec = &recs[0];

    uint32_t alg_enc = s->s3->tmp.new_cipher->algorithm_enc;

    uint32_t alg_enc;



    if (n_recs != 1) {

        /* Should not happen */
@@ -52,8 +53,18 @@ int tls13_enc(SSL *s, SSL3_RECORD *recs, size_t n_recs, int send) 
        rec->input = rec->data;

        return 1;

    }



    ivlen = EVP_CIPHER_CTX_iv_length(ctx);



    /*

     * To get here we must have selected a ciphersuite - otherwise ctx would

     * be NULL

     */

    assert(s->s3->tmp.new_cipher != NULL);

    if (s->s3->tmp.new_cipher == NULL)

        return -1;

    alg_enc = s->s3->tmp.new_cipher->algorithm_enc;



    if (alg_enc & SSL_AESCCM) {

        if (alg_enc & (SSL_AES128CCM8 | SSL_AES256CCM8))

            taglen = EVP_CCM8_TLS_TAG_LEN;

test/tls13encryptiontest.c

+18 −0
Original line number Diff line number Diff line
@@ -34,6 +34,10 @@ typedef struct { 


static RECORD_DATA refdata[] = {

    {

        /*

         * Server: EncryptedExtensions, Certificate, CertificateVerify and

         *         Finished

         */

        {

            "0800001e001c000a00140012001d001700180019010001010102010301040000"

            "00000b0001b9000001b50001b0308201ac30820115a003020102020102300d06"
@@ -85,6 +89,7 @@ static RECORD_DATA refdata[] = { 
        "0000000000000000"

    },

    {

        /* Client: Finished */

        {

            "1400002078367856d3c8cc4e0a95eb98906ca7a48bd3cc7029f48bd4ae0dc91a"

            "b903ca8916","",""
@@ -98,6 +103,7 @@ static RECORD_DATA refdata[] = { 
        "0000000000000000"

    },

    {

        /* Server: NewSessionTicket */

        {

            "040000a60002a3004abe594b00924e535321cadc96238da09caf9b02fecafdd6"

            "5e3e418f03e43772cf512ed8066100503b1c08abbbf298a9d138ce821dd12fe1"
@@ -119,6 +125,7 @@ static RECORD_DATA refdata[] = { 
        "0000000000000000"

    },

    {

        /* Client: Application Data */

        {

            "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"

            "202122232425262728292a2b2c2d2e2f303117","",""
@@ -133,6 +140,7 @@ static RECORD_DATA refdata[] = { 
        "0000000000000000"

    },

    {

        /* Server: Application Data */

        {

            "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"

            "202122232425262728292a2b2c2d2e2f303117","",""
@@ -147,6 +155,7 @@ static RECORD_DATA refdata[] = { 
        "0000000000000001"

    },

    {

        /* Client: CloseNotify */

        {

            "010015","",""

        },
@@ -158,6 +167,7 @@ static RECORD_DATA refdata[] = { 
        "0000000000000001"

    },

    {

        /* Server: CloseNotify */

        {

            "010015","",""

        },
@@ -281,6 +291,8 @@ static int test_record(SSL3_RECORD *rec, RECORD_DATA *recd, int enc) 
    return ret;

}



#define TLS13_AES_128_GCM_SHA256_BYTES  ((const unsigned char *)"\x13\x01")



static int test_tls13_encryption(void)

{

    SSL_CTX *ctx = NULL;
@@ -312,6 +324,12 @@ static int test_tls13_encryption(void) 
        goto err;

    }



    s->s3->tmp.new_cipher = SSL_CIPHER_find(s, TLS13_AES_128_GCM_SHA256_BYTES);

    if (s->s3->tmp.new_cipher == NULL) {

        fprintf(stderr, "Failed to find cipher\n");

        goto err;

    }



    for (ctr = 0; ctr < OSSL_NELEM(refdata); ctr++) {

        /* Load the record */

        ivlen = EVP_CIPHER_iv_length(ciph);