Commit 97cc9c9b authored by Shane Lontis's avatar Shane Lontis Committed by Pauli
Browse files

Coverity: hkdf ENV_MD_size() is an int that can be negative 



Reviewed-by: default avatarTim Hudson <tjh@openssl.org>
Reviewed-by: default avatarPaul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/8692)
parent e9cfa192

crypto/kdf/hkdf.c

+27 −7
Original line number Diff line number Diff line
@@ -182,6 +182,8 @@ static int kdf_hkdf_ctrl_str(EVP_KDF_IMPL *impl, const char *type, 


static size_t kdf_hkdf_size(EVP_KDF_IMPL *impl)

{

    int sz;



    if (impl->mode != EVP_KDF_HKDF_MODE_EXTRACT_ONLY)

        return SIZE_MAX;
@@ -189,7 +191,11 @@ static size_t kdf_hkdf_size(EVP_KDF_IMPL *impl) 
        KDFerr(KDF_F_KDF_HKDF_SIZE, KDF_R_MISSING_MESSAGE_DIGEST);

        return 0;

    }

    return EVP_MD_size(impl->md);

    sz = EVP_MD_size(impl->md);

    if (sz < 0)

        return 0;



    return sz;

}



static int kdf_hkdf_derive(EVP_KDF_IMPL *impl, unsigned char *key,
@@ -241,8 +247,13 @@ static int HKDF(const EVP_MD *evp_md, 
                unsigned char *okm, size_t okm_len)

{

    unsigned char prk[EVP_MAX_MD_SIZE];

    int ret;

    size_t prk_len = EVP_MD_size(evp_md);

    int ret, sz;

    size_t prk_len;



    sz = EVP_MD_size(evp_md);

    if (sz < 0)

        return 0;

    prk_len = (size_t)sz;



    if (!HKDF_Extract(evp_md, salt, salt_len, key, key_len, prk, prk_len))

        return 0;
@@ -258,7 +269,11 @@ static int HKDF_Extract(const EVP_MD *evp_md, 
                        const unsigned char *key, size_t key_len,

                        unsigned char *prk, size_t prk_len)

{

    if (prk_len != (size_t)EVP_MD_size(evp_md)) {

    int sz = EVP_MD_size(evp_md);



    if (sz < 0)

        return 0;

    if (prk_len != (size_t)sz) {

        KDFerr(KDF_F_HKDF_EXTRACT, KDF_R_WRONG_OUTPUT_BUFFER_SIZE);

        return 0;

    }
@@ -271,11 +286,16 @@ static int HKDF_Expand(const EVP_MD *evp_md, 
                       unsigned char *okm, size_t okm_len)

{

    HMAC_CTX *hmac;

    int ret = 0;

    int ret = 0, sz;

    unsigned int i;

    unsigned char prev[EVP_MAX_MD_SIZE];

    size_t done_len = 0, dig_len = EVP_MD_size(evp_md);

    size_t n = okm_len / dig_len;

    size_t done_len = 0, dig_len, n;



    sz = EVP_MD_size(evp_md);

    if (sz <= 0)

        return 0;

    dig_len = (size_t)sz;

    n = okm_len / dig_len;



    if (okm_len % dig_len)

        n++;