From 48e3cf25a80db9a2991daccb0d8d1848065bca63 Mon Sep 17 00:00:00 2001 From: Jiasheng Jiang Date: Fri, 22 Mar 2024 16:00:39 +0000 Subject: [PATCH] ssl/statem: Replace size_t with int and add the checks Replace the type of variables with int to avoid implicit conversion when it is assigned by EVP_MD_get_size(). Moreover, add the checks to avoid integer overflow. Fixes: 6594189 ("Merge early_data_info extension into early_data") Fixes: 9368f86 ("Add TLSv1.3 client side external PSK support") Fixes: 1053a6e ("Implement Server side of PSK extension parsing") Signed-off-by: Jiasheng Jiang Reviewed-by: Tom Cosgrove Reviewed-by: Tomas Mraz (Merged from https://github.com/openssl/openssl/pull/23937) --- ssl/statem/extensions_clnt.c | 15 +++++++++++++-- ssl/statem/extensions_srvr.c | 7 +++++-- 2 files changed, 18 insertions(+), 4 deletions(-) diff --git a/ssl/statem/extensions_clnt.c b/ssl/statem/extensions_clnt.c index 77fe629132..ef51c61ef3 100644 --- a/ssl/statem/extensions_clnt.c +++ b/ssl/statem/extensions_clnt.c @@ -979,8 +979,12 @@ EXT_RETURN tls_construct_ctos_padding(SSL_CONNECTION *s, WPACKET *pkt, * Add the fixed PSK overhead, the identity length and the binder * length. */ + int md_size = EVP_MD_get_size(md); + + if (md_size <= 0) + return EXT_RETURN_FAIL; hlen += PSK_PRE_BINDER_OVERHEAD + s->session->ext.ticklen - + EVP_MD_get_size(md); + + md_size; } } @@ -1019,7 +1023,8 @@ EXT_RETURN tls_construct_ctos_psk(SSL_CONNECTION *s, WPACKET *pkt, { #ifndef OPENSSL_NO_TLS1_3 uint32_t agesec, agems = 0; - size_t reshashsize = 0, pskhashsize = 0, binderoffset, msglen; + size_t binderoffset, msglen; + int reshashsize = 0, pskhashsize = 0; unsigned char *resbinder = NULL, *pskbinder = NULL, *msgstart = NULL; const EVP_MD *handmd = NULL, *mdres = NULL, *mdpsk = NULL; int dores = 0; @@ -1115,6 +1120,8 @@ EXT_RETURN tls_construct_ctos_psk(SSL_CONNECTION *s, WPACKET *pkt, agems += s->session->ext.tick_age_add; reshashsize = EVP_MD_get_size(mdres); + if (reshashsize <= 0) + goto dopsksess; s->ext.tick_identity++; dores = 1; } @@ -1144,6 +1151,10 @@ EXT_RETURN tls_construct_ctos_psk(SSL_CONNECTION *s, WPACKET *pkt, } pskhashsize = EVP_MD_get_size(mdpsk); + if (pskhashsize <= 0) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK); + return EXT_RETURN_FAIL; + } } /* Create the extension, but skip over the binder for now */ diff --git a/ssl/statem/extensions_srvr.c b/ssl/statem/extensions_srvr.c index 21db977c88..2962a0bdcd 100644 --- a/ssl/statem/extensions_srvr.c +++ b/ssl/statem/extensions_srvr.c @@ -1020,7 +1020,8 @@ int tls_parse_ctos_psk(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, X509 *x, size_t chainidx) { PACKET identities, binders, binder; - size_t binderoffset, hashsize; + size_t binderoffset; + int hashsize; SSL_SESSION *sess = NULL; unsigned int id, i, ext = 0; const EVP_MD *md = NULL; @@ -1221,6 +1222,8 @@ int tls_parse_ctos_psk(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, binderoffset = PACKET_data(pkt) - (const unsigned char *)s->init_buf->data; hashsize = EVP_MD_get_size(md); + if (hashsize <= 0) + goto err; if (!PACKET_get_length_prefixed_2(pkt, &binders)) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); @@ -1234,7 +1237,7 @@ int tls_parse_ctos_psk(SSL_CONNECTION *s, PACKET *pkt, unsigned int context, } } - if (PACKET_remaining(&binder) != hashsize) { + if (PACKET_remaining(&binder) != (size_t)hashsize) { SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_BAD_EXTENSION); goto err; }