From 63ff242131c8e6d98917456f71f6d33b9ef3a763 Mon Sep 17 00:00:00 2001
From: Jakub Jelen <jjelen@redhat.com>
Date: Fri, 15 Dec 2023 12:55:27 +0100
Subject: [PATCH 16/20] CVE-2023-6918: Remove unused evp functions and types

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
---
 include/libssh/libcrypto.h     |  5 ---
 include/libssh/libgcrypt.h     |  1 -
 include/libssh/libmbedcrypto.h |  1 -
 include/libssh/wrapper.h       |  4 --
 src/libcrypto.c                | 54 -------------------------
 src/libgcrypt.c                | 53 ------------------------
 src/libmbedcrypto.c            | 74 ----------------------------------
 7 files changed, 192 deletions(-)

diff --git a/include/libssh/libcrypto.h b/include/libssh/libcrypto.h
index 16e5f98f..87f30a4d 100644
--- a/include/libssh/libcrypto.h
+++ b/include/libssh/libcrypto.h
@@ -39,11 +39,6 @@ typedef EVP_MD_CTX* SHA384CTX;
 typedef EVP_MD_CTX* SHA512CTX;
 typedef EVP_MD_CTX* MD5CTX;
 typedef EVP_MD_CTX* HMACCTX;
-#ifdef HAVE_ECC
-typedef EVP_MD_CTX *EVPCTX;
-#else
-typedef void *EVPCTX;
-#endif
 
 #define SHA_DIGEST_LEN SHA_DIGEST_LENGTH
 #define SHA256_DIGEST_LEN SHA256_DIGEST_LENGTH
diff --git a/include/libssh/libgcrypt.h b/include/libssh/libgcrypt.h
index e4087fd2..c6afc22e 100644
--- a/include/libssh/libgcrypt.h
+++ b/include/libssh/libgcrypt.h
@@ -32,7 +32,6 @@ typedef gcry_md_hd_t SHA384CTX;
 typedef gcry_md_hd_t SHA512CTX;
 typedef gcry_md_hd_t MD5CTX;
 typedef gcry_md_hd_t HMACCTX;
-typedef gcry_md_hd_t EVPCTX;
 #define SHA_DIGEST_LENGTH 20
 #define SHA_DIGEST_LEN SHA_DIGEST_LENGTH
 #define MD5_DIGEST_LEN 16
diff --git a/include/libssh/libmbedcrypto.h b/include/libssh/libmbedcrypto.h
index e6fc393c..540a025b 100644
--- a/include/libssh/libmbedcrypto.h
+++ b/include/libssh/libmbedcrypto.h
@@ -41,7 +41,6 @@ typedef mbedtls_md_context_t *SHA384CTX;
 typedef mbedtls_md_context_t *SHA512CTX;
 typedef mbedtls_md_context_t *MD5CTX;
 typedef mbedtls_md_context_t *HMACCTX;
-typedef mbedtls_md_context_t *EVPCTX;
 
 #define SHA_DIGEST_LENGTH 20
 #define SHA_DIGEST_LEN SHA_DIGEST_LENGTH
diff --git a/include/libssh/wrapper.h b/include/libssh/wrapper.h
index 36589cff..07e64018 100644
--- a/include/libssh/wrapper.h
+++ b/include/libssh/wrapper.h
@@ -95,10 +95,6 @@ void sha512_update(SHA512CTX c, const void *data, size_t len);
 void sha512_final(unsigned char *md,SHA512CTX c);
 void sha512(const unsigned char *digest, size_t len, unsigned char *hash);
 
-void evp(int nid, unsigned char *digest, size_t len, unsigned char *hash, unsigned int *hlen);
-EVPCTX evp_init(int nid);
-void evp_update(EVPCTX ctx, const void *data, size_t len);
-void evp_final(EVPCTX ctx, unsigned char *md, unsigned int *mdlen);
 
 HMACCTX hmac_init(const void *key,size_t len, enum ssh_hmac_e type);
 int hmac_update(HMACCTX c, const void *data, size_t len);
diff --git a/src/libcrypto.c b/src/libcrypto.c
index ebdca6e0..4f945d90 100644
--- a/src/libcrypto.c
+++ b/src/libcrypto.c
@@ -125,60 +125,6 @@ ENGINE *pki_get_engine(void)
     return engine;
 }
 
-#ifdef HAVE_OPENSSL_ECC
-static const EVP_MD *nid_to_evpmd(int nid)
-{
-    switch (nid) {
-        case NID_X9_62_prime256v1:
-            return EVP_sha256();
-        case NID_secp384r1:
-            return EVP_sha384();
-        case NID_secp521r1:
-            return EVP_sha512();
-        default:
-            return NULL;
-    }
-
-    return NULL;
-}
-
-void evp(int nid, unsigned char *digest, size_t len, unsigned char *hash, unsigned int *hlen)
-{
-    const EVP_MD *evp_md = nid_to_evpmd(nid);
-    EVP_MD_CTX *md = EVP_MD_CTX_new();
-
-    EVP_DigestInit(md, evp_md);
-    EVP_DigestUpdate(md, digest, len);
-    EVP_DigestFinal(md, hash, hlen);
-    EVP_MD_CTX_free(md);
-}
-
-EVPCTX evp_init(int nid)
-{
-    const EVP_MD *evp_md = nid_to_evpmd(nid);
-
-    EVPCTX ctx = EVP_MD_CTX_new();
-    if (ctx == NULL) {
-        return NULL;
-    }
-
-    EVP_DigestInit(ctx, evp_md);
-
-    return ctx;
-}
-
-void evp_update(EVPCTX ctx, const void *data, size_t len)
-{
-    EVP_DigestUpdate(ctx, data, len);
-}
-
-void evp_final(EVPCTX ctx, unsigned char *md, unsigned int *mdlen)
-{
-    EVP_DigestFinal(ctx, md, mdlen);
-    EVP_MD_CTX_free(ctx);
-}
-#endif /* HAVE_OPENSSL_ECC */
-
 #ifdef HAVE_OPENSSL_EVP_KDF_CTX
 #if OPENSSL_VERSION_NUMBER < 0x30000000L
 static const EVP_MD *sshkdf_digest_to_md(enum ssh_kdf_digest digest_type)
diff --git a/src/libgcrypt.c b/src/libgcrypt.c
index 2e44a53c..f410d997 100644
--- a/src/libgcrypt.c
+++ b/src/libgcrypt.c
@@ -69,59 +69,6 @@ static int alloc_key(struct ssh_cipher_struct *cipher) {
 void ssh_reseed(void){
 }
 
-#ifdef HAVE_GCRYPT_ECC
-static int nid_to_md_algo(int nid)
-{
-    switch (nid) {
-    case NID_gcrypt_nistp256:
-        return GCRY_MD_SHA256;
-    case NID_gcrypt_nistp384:
-        return GCRY_MD_SHA384;
-    case NID_gcrypt_nistp521:
-        return GCRY_MD_SHA512;
-    }
-    return GCRY_MD_NONE;
-}
-
-void evp(int nid, unsigned char *digest, size_t len,
-         unsigned char *hash, unsigned int *hlen)
-{
-    int algo = nid_to_md_algo(nid);
-
-    /* Note: What gcrypt calls 'hash' is called 'digest' here and
-       vice-versa.  */
-    gcry_md_hash_buffer(algo, hash, digest, len);
-    *hlen = gcry_md_get_algo_dlen(algo);
-}
-
-EVPCTX evp_init(int nid)
-{
-    gcry_error_t err;
-    int algo = nid_to_md_algo(nid);
-    EVPCTX ctx;
-
-    err = gcry_md_open(&ctx, algo, 0);
-    if (err) {
-        return NULL;
-    }
-
-    return ctx;
-}
-
-void evp_update(EVPCTX ctx, const void *data, size_t len)
-{
-    gcry_md_write(ctx, data, len);
-}
-
-void evp_final(EVPCTX ctx, unsigned char *md, unsigned int *mdlen)
-{
-    int algo = gcry_md_get_algo(ctx);
-    *mdlen = gcry_md_get_algo_dlen(algo);
-    memcpy(md, gcry_md_read(ctx, algo), *mdlen);
-    gcry_md_close(ctx);
-}
-#endif
-
 int ssh_kdf(struct ssh_crypto_struct *crypto,
             unsigned char *key, size_t key_len,
             uint8_t key_type, unsigned char *output,
diff --git a/src/libmbedcrypto.c b/src/libmbedcrypto.c
index 594e5369..caa3b6e9 100644
--- a/src/libmbedcrypto.c
+++ b/src/libmbedcrypto.c
@@ -51,80 +51,6 @@ void ssh_reseed(void)
     mbedtls_ctr_drbg_reseed(&ssh_mbedtls_ctr_drbg, NULL, 0);
 }
 
-static mbedtls_md_type_t nid_to_md_algo(int nid)
-{
-    switch (nid) {
-        case NID_mbedtls_nistp256:
-            return MBEDTLS_MD_SHA256;
-        case NID_mbedtls_nistp384:
-            return MBEDTLS_MD_SHA384;
-        case NID_mbedtls_nistp521:
-            return MBEDTLS_MD_SHA512;
-    }
-    return MBEDTLS_MD_NONE;
-}
-
-void evp(int nid, unsigned char *digest, size_t len,
-        unsigned char *hash, unsigned int *hlen)
-{
-    mbedtls_md_type_t algo = nid_to_md_algo(nid);
-    const mbedtls_md_info_t *md_info =
-        mbedtls_md_info_from_type(algo);
-
-
-    if (md_info != NULL) {
-        *hlen = mbedtls_md_get_size(md_info);
-        mbedtls_md(md_info, digest, len, hash);
-    }
-}
-
-EVPCTX evp_init(int nid)
-{
-    EVPCTX ctx = NULL;
-    int rc;
-    mbedtls_md_type_t algo = nid_to_md_algo(nid);
-    const mbedtls_md_info_t *md_info =
-        mbedtls_md_info_from_type(algo);
-
-    if (md_info == NULL) {
-        return NULL;
-    }
-
-    ctx = malloc(sizeof(mbedtls_md_context_t));
-    if (ctx == NULL) {
-        return NULL;
-    }
-
-    mbedtls_md_init(ctx);
-
-    rc = mbedtls_md_setup(ctx, md_info, 0);
-    if (rc != 0) {
-        SAFE_FREE(ctx);
-        return NULL;
-    }
-
-    rc = mbedtls_md_starts(ctx);
-    if (rc != 0) {
-        SAFE_FREE(ctx);
-        return NULL;
-    }
-
-    return ctx;
-}
-
-void evp_update(EVPCTX ctx, const void *data, size_t len)
-{
-    mbedtls_md_update(ctx, data, len);
-}
-
-void evp_final(EVPCTX ctx, unsigned char *md, unsigned int *mdlen)
-{
-    *mdlen = mbedtls_md_get_size(ctx->MBEDTLS_PRIVATE(md_info));
-    mbedtls_md_finish(ctx, md);
-    mbedtls_md_free(ctx);
-    SAFE_FREE(ctx);
-}
-
 int ssh_kdf(struct ssh_crypto_struct *crypto,
             unsigned char *key, size_t key_len,
             uint8_t key_type, unsigned char *output,
-- 
2.33.0