From 6ec6d5207187dbc1dbd971bd50ea17c9a94906d0 Mon Sep 17 00:00:00 2001 From: "Dr. Stephen Henson" Date: Wed, 8 Jun 2016 19:01:42 +0100 Subject: [PATCH] Don't skip leading zeroes in PSK keys. Don't use BN_hex2bn() for PSK key conversion as the conversion to BN and back removes leading zeroes, use OPENSSL_hexstr2buf() instead. RT#4554 Reviewed-by: Matt Caswell --- apps/s_client.c | 32 +++++++++++++++----------------- apps/s_server.c | 32 +++++++++++++------------------- 2 files changed, 28 insertions(+), 36 deletions(-) diff --git a/apps/s_client.c b/apps/s_client.c index aa21ef6f41..205f283370 100644 --- a/apps/s_client.c +++ b/apps/s_client.c @@ -157,9 +157,9 @@ static unsigned int psk_client_cb(SSL *ssl, const char *hint, char *identity, unsigned char *psk, unsigned int max_psk_len) { - unsigned int psk_len = 0; int ret; - BIGNUM *bn = NULL; + long key_len; + unsigned char *key; if (c_debug) BIO_printf(bio_c_out, "psk_client_cb\n"); @@ -180,31 +180,29 @@ static unsigned int psk_client_cb(SSL *ssl, const char *hint, char *identity, if (c_debug) BIO_printf(bio_c_out, "created identity '%s' len=%d\n", identity, ret); - ret = BN_hex2bn(&bn, psk_key); - if (!ret) { - BIO_printf(bio_err, "Could not convert PSK key '%s' to BIGNUM\n", + + /* convert the PSK key to binary */ + key = OPENSSL_hexstr2buf(psk_key, &key_len); + if (key == NULL) { + BIO_printf(bio_err, "Could not convert PSK key '%s' to buffer\n", psk_key); - BN_free(bn); return 0; } - - if ((unsigned int)BN_num_bytes(bn) > max_psk_len) { + if (key_len > max_psk_len) { BIO_printf(bio_err, - "psk buffer of callback is too small (%d) for key (%d)\n", - max_psk_len, BN_num_bytes(bn)); - BN_free(bn); + "psk buffer of callback is too small (%d) for key (%ld)\n", + max_psk_len, key_len); + OPENSSL_free(key); return 0; } - psk_len = BN_bn2bin(bn, psk); - BN_free(bn); - if (psk_len == 0) - goto out_err; + memcpy(psk, key, key_len); + OPENSSL_free(key); if (c_debug) - BIO_printf(bio_c_out, "created PSK len=%d\n", psk_len); + BIO_printf(bio_c_out, "created PSK len=%ld\n", key_len); - return psk_len; + return key_len; out_err: if (c_debug) BIO_printf(bio_err, "Error in PSK client callback\n"); diff --git a/apps/s_server.c b/apps/s_server.c index dce02f036c..9188ecf29c 100644 --- a/apps/s_server.c +++ b/apps/s_server.c @@ -166,9 +166,8 @@ static unsigned int psk_server_cb(SSL *ssl, const char *identity, unsigned char *psk, unsigned int max_psk_len) { - unsigned int psk_len = 0; - int ret; - BIGNUM *bn = NULL; + long key_len = 0; + unsigned char *key; if (s_debug) BIO_printf(bio_s_out, "psk_server_cb\n"); @@ -190,31 +189,26 @@ static unsigned int psk_server_cb(SSL *ssl, const char *identity, BIO_printf(bio_s_out, "PSK client identity found\n"); /* convert the PSK key to binary */ - ret = BN_hex2bn(&bn, psk_key); - if (!ret) { - BIO_printf(bio_err, "Could not convert PSK key '%s' to BIGNUM\n", + key = OPENSSL_hexstr2buf(psk_key, &key_len); + if (key == NULL) { + BIO_printf(bio_err, "Could not convert PSK key '%s' to buffer\n", psk_key); - BN_free(bn); return 0; } - if (BN_num_bytes(bn) > (int)max_psk_len) { + if (key_len > (int)max_psk_len) { BIO_printf(bio_err, - "psk buffer of callback is too small (%d) for key (%d)\n", - max_psk_len, BN_num_bytes(bn)); - BN_free(bn); + "psk buffer of callback is too small (%d) for key (%ld)\n", + max_psk_len, key_len); + OPENSSL_free(key); return 0; } - ret = BN_bn2bin(bn, psk); - BN_free(bn); - - if (ret < 0) - goto out_err; - psk_len = (unsigned int)ret; + memcpy(psk, key, key_len); + OPENSSL_free(key); if (s_debug) - BIO_printf(bio_s_out, "fetched PSK len=%d\n", psk_len); - return psk_len; + BIO_printf(bio_s_out, "fetched PSK len=%ld\n", key_len); + return key_len; out_err: if (s_debug) BIO_printf(bio_err, "Error in PSK server callback\n"); -- 2.25.1