mirror of
https://git.libssh.org/projects/libssh.git
synced 2025-08-10 06:23:01 +03:00
Revert "kex: server fix for first_kex_packet_follows"
The patch breaks the client with ECDSA.
This reverts commit 5865b9436f.
This commit is contained in:
Andreas Schneider
@@ -127,15 +127,6 @@ struct ssh_session_struct {
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struct ssh_agent_state_struct *agent_state;
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struct ssh_auth_auto_state_struct *auth_auto_state;
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/*
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* RFC 4253, 7.1: if the first_kex_packet_follows flag was set in
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* the received SSH_MSG_KEXINIT, but the guess was wrong, this
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* field will be set such that the following guessed packet will
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* be ignored. Once that packet has been received and ignored,
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* this field is cleared.
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*/
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int first_kex_follows_guess_wrong;
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ssh_buffer in_hashbuf;
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ssh_buffer out_hashbuf;
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struct ssh_crypto_struct *current_crypto;
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372
src/dh.c
372
src/dh.c
@@ -587,234 +587,218 @@ error:
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return SSH_ERROR;
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}
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/*
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static void sha_add(ssh_string str,SHACTX ctx){
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sha1_update(ctx,str,string_len(str)+4);
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#ifdef DEBUG_CRYPTO
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ssh_print_hexa("partial hashed sessionid",str,string_len(str)+4);
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#endif
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}
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*/
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int make_sessionid(ssh_session session) {
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ssh_string num = NULL;
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ssh_string str = NULL;
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ssh_buffer server_hash = NULL;
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ssh_buffer client_hash = NULL;
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ssh_buffer buf = NULL;
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uint32_t len;
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int rc = SSH_ERROR;
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ssh_string num = NULL;
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ssh_string str = NULL;
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ssh_buffer server_hash = NULL;
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ssh_buffer client_hash = NULL;
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ssh_buffer buf = NULL;
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uint32_t len;
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int rc = SSH_ERROR;
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buf = ssh_buffer_new();
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if (buf == NULL) {
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return rc;
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}
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buf = ssh_buffer_new();
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if (buf == NULL) {
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return rc;
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}
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str = ssh_string_from_char(session->clientbanner);
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if (str == NULL) {
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goto error;
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}
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str = ssh_string_from_char(session->clientbanner);
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if (str == NULL) {
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goto error;
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}
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rc = buffer_add_ssh_string(buf, str);
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if (rc < 0) {
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goto error;
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}
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ssh_string_free(str);
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if (buffer_add_ssh_string(buf, str) < 0) {
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goto error;
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}
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ssh_string_free(str);
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str = ssh_string_from_char(session->serverbanner);
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if (str == NULL) {
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goto error;
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}
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str = ssh_string_from_char(session->serverbanner);
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if (str == NULL) {
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goto error;
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}
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rc = buffer_add_ssh_string(buf, str);
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if (rc < 0) {
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goto error;
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}
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if (buffer_add_ssh_string(buf, str) < 0) {
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goto error;
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}
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if (session->client) {
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server_hash = session->in_hashbuf;
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client_hash = session->out_hashbuf;
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} else {
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server_hash = session->out_hashbuf;
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client_hash = session->in_hashbuf;
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}
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if (session->client) {
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server_hash = session->in_hashbuf;
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client_hash = session->out_hashbuf;
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} else {
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server_hash = session->out_hashbuf;
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client_hash = session->in_hashbuf;
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}
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/*
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* Handle the two final fields for the KEXINIT message (RFC 4253 7.1):
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*
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* boolean first_kex_packet_follows
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* uint32 0 (reserved for future extension)
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*/
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rc = buffer_add_u8(server_hash, 0);
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if (rc < 0) {
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goto error;
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}
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rc = buffer_add_u32(server_hash, 0);
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if (rc < 0) {
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goto error;
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}
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if (buffer_add_u32(server_hash, 0) < 0) {
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goto error;
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}
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if (buffer_add_u8(server_hash, 0) < 0) {
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goto error;
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}
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if (buffer_add_u32(client_hash, 0) < 0) {
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goto error;
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}
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if (buffer_add_u8(client_hash, 0) < 0) {
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goto error;
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}
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/* These fields are handled for the server case in ssh_packet_kexinit. */
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if (session->client) {
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rc = buffer_add_u8(client_hash, 0);
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if (rc < 0) {
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goto error;
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}
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rc = buffer_add_u32(client_hash, 0);
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if (rc < 0) {
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goto error;
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}
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}
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len = ntohl(buffer_get_rest_len(client_hash));
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if (buffer_add_u32(buf,len) < 0) {
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goto error;
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}
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if (ssh_buffer_add_data(buf, buffer_get_rest(client_hash),
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buffer_get_rest_len(client_hash)) < 0) {
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goto error;
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}
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len = ntohl(buffer_get_rest_len(client_hash));
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rc = buffer_add_u32(buf,len);
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if (rc < 0) {
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goto error;
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}
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rc = ssh_buffer_add_data(buf, buffer_get_rest(client_hash),
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buffer_get_rest_len(client_hash));
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if (rc < 0) {
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goto error;
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}
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len = ntohl(buffer_get_rest_len(server_hash));
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if (buffer_add_u32(buf, len) < 0) {
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goto error;
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}
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if (ssh_buffer_add_data(buf, buffer_get_rest(server_hash),
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buffer_get_rest_len(server_hash)) < 0) {
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goto error;
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}
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len = ntohl(buffer_get_rest_len(server_hash));
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rc = buffer_add_u32(buf, len);
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if (rc < 0) {
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goto error;
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}
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rc = ssh_buffer_add_data(buf, buffer_get_rest(server_hash),
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buffer_get_rest_len(server_hash));
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if (rc < 0) {
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goto error;
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}
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len = ssh_string_len(session->next_crypto->server_pubkey) + 4;
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if (ssh_buffer_add_data(buf, session->next_crypto->server_pubkey, len) < 0) {
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goto error;
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}
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if(session->next_crypto->kex_type == SSH_KEX_DH_GROUP1_SHA1 ||
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session->next_crypto->kex_type == SSH_KEX_DH_GROUP14_SHA1) {
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len = ssh_string_len(session->next_crypto->server_pubkey) + 4;
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rc = ssh_buffer_add_data(buf, session->next_crypto->server_pubkey, len);
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if (rc < 0) {
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goto error;
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}
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if (session->next_crypto->kex_type == SSH_KEX_DH_GROUP1_SHA1 ||
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session->next_crypto->kex_type == SSH_KEX_DH_GROUP14_SHA1) {
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num = make_bignum_string(session->next_crypto->e);
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if (num == NULL) {
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goto error;
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}
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len = ssh_string_len(num) + 4;
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rc = ssh_buffer_add_data(buf, num, len);
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if (rc < 0) {
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goto error;
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}
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ssh_string_free(num);
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num = make_bignum_string(session->next_crypto->f);
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if (num == NULL) {
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goto error;
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}
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len = ssh_string_len(num) + 4;
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rc = ssh_buffer_add_data(buf, num, len);
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if (rc < 0) {
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goto error;
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}
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ssh_string_free(num);
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#ifdef HAVE_ECDH
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} else if (session->next_crypto->kex_type == SSH_KEX_ECDH_SHA2_NISTP256) {
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if (session->next_crypto->ecdh_client_pubkey == NULL ||
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session->next_crypto->ecdh_server_pubkey == NULL) {
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SSH_LOG(SSH_LOG_WARNING, "ECDH parameted missing");
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goto error;
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}
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rc = buffer_add_ssh_string(buf,session->next_crypto->ecdh_client_pubkey);
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if (rc < 0) {
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goto error;
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}
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rc = buffer_add_ssh_string(buf,session->next_crypto->ecdh_server_pubkey);
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if (rc < 0) {
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goto error;
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}
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#endif
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#ifdef HAVE_CURVE25519
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} else if (session->next_crypto->kex_type == SSH_KEX_CURVE25519_SHA256_LIBSSH_ORG) {
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rc = buffer_add_u32(buf, htonl(CURVE25519_PUBKEY_SIZE));
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rc += ssh_buffer_add_data(buf, session->next_crypto->curve25519_client_pubkey,
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CURVE25519_PUBKEY_SIZE);
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rc += buffer_add_u32(buf, htonl(CURVE25519_PUBKEY_SIZE));
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rc += ssh_buffer_add_data(buf, session->next_crypto->curve25519_server_pubkey,
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CURVE25519_PUBKEY_SIZE);
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if (rc != SSH_OK) {
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goto error;
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}
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#endif
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}
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num = make_bignum_string(session->next_crypto->k);
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num = make_bignum_string(session->next_crypto->e);
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if (num == NULL) {
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goto error;
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goto error;
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}
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len = ssh_string_len(num) + 4;
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rc = ssh_buffer_add_data(buf, num, len);
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if (ssh_buffer_add_data(buf, num, len) < 0) {
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goto error;
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}
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ssh_string_free(num);
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num = make_bignum_string(session->next_crypto->f);
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if (num == NULL) {
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goto error;
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}
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len = ssh_string_len(num) + 4;
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if (ssh_buffer_add_data(buf, num, len) < 0) {
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goto error;
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}
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ssh_string_free(num);
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#ifdef HAVE_ECDH
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} else if (session->next_crypto->kex_type == SSH_KEX_ECDH_SHA2_NISTP256){
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if(session->next_crypto->ecdh_client_pubkey == NULL ||
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session->next_crypto->ecdh_server_pubkey == NULL){
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SSH_LOG(SSH_LOG_WARNING, "ECDH parameted missing");
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goto error;
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}
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rc = buffer_add_ssh_string(buf,session->next_crypto->ecdh_client_pubkey);
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if (rc < 0) {
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goto error;
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}
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rc = buffer_add_ssh_string(buf,session->next_crypto->ecdh_server_pubkey);
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if (rc < 0) {
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goto error;
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}
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#endif
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#ifdef HAVE_CURVE25519
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} else if(session->next_crypto->kex_type == SSH_KEX_CURVE25519_SHA256_LIBSSH_ORG){
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rc = buffer_add_u32(buf, htonl(CURVE25519_PUBKEY_SIZE));
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rc += ssh_buffer_add_data(buf, session->next_crypto->curve25519_client_pubkey,
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CURVE25519_PUBKEY_SIZE);
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rc += buffer_add_u32(buf, htonl(CURVE25519_PUBKEY_SIZE));
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rc += ssh_buffer_add_data(buf, session->next_crypto->curve25519_server_pubkey,
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CURVE25519_PUBKEY_SIZE);
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if (rc != SSH_OK) {
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goto error;
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}
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#endif
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}
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num = make_bignum_string(session->next_crypto->k);
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if (num == NULL) {
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goto error;
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}
|
||||
|
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len = ssh_string_len(num) + 4;
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if (ssh_buffer_add_data(buf, num, len) < 0) {
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goto error;
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}
|
||||
|
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#ifdef DEBUG_CRYPTO
|
||||
ssh_print_hexa("hash buffer", ssh_buffer_get_begin(buf), ssh_buffer_get_len(buf));
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ssh_print_hexa("hash buffer", ssh_buffer_get_begin(buf), ssh_buffer_get_len(buf));
|
||||
#endif
|
||||
|
||||
switch (session->next_crypto->kex_type) {
|
||||
switch(session->next_crypto->kex_type){
|
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case SSH_KEX_DH_GROUP1_SHA1:
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||||
case SSH_KEX_DH_GROUP14_SHA1:
|
||||
session->next_crypto->digest_len = SHA_DIGEST_LENGTH;
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session->next_crypto->mac_type = SSH_MAC_SHA1;
|
||||
session->next_crypto->secret_hash = malloc(session->next_crypto->digest_len);
|
||||
if (session->next_crypto->secret_hash == NULL) {
|
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ssh_set_error_oom(session);
|
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goto error;
|
||||
}
|
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sha1(buffer_get_rest(buf), buffer_get_rest_len(buf),
|
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session->next_crypto->secret_hash);
|
||||
break;
|
||||
session->next_crypto->digest_len = SHA_DIGEST_LENGTH;
|
||||
session->next_crypto->mac_type = SSH_MAC_SHA1;
|
||||
session->next_crypto->secret_hash = malloc(session->next_crypto->digest_len);
|
||||
if(session->next_crypto->secret_hash == NULL){
|
||||
ssh_set_error_oom(session);
|
||||
goto error;
|
||||
}
|
||||
sha1(buffer_get_rest(buf), buffer_get_rest_len(buf),
|
||||
session->next_crypto->secret_hash);
|
||||
break;
|
||||
case SSH_KEX_ECDH_SHA2_NISTP256:
|
||||
case SSH_KEX_CURVE25519_SHA256_LIBSSH_ORG:
|
||||
session->next_crypto->digest_len = SHA256_DIGEST_LENGTH;
|
||||
session->next_crypto->mac_type = SSH_MAC_SHA256;
|
||||
session->next_crypto->secret_hash = malloc(session->next_crypto->digest_len);
|
||||
if (session->next_crypto->secret_hash == NULL) {
|
||||
ssh_set_error_oom(session);
|
||||
goto error;
|
||||
}
|
||||
sha256(buffer_get_rest(buf), buffer_get_rest_len(buf),
|
||||
session->next_crypto->secret_hash);
|
||||
break;
|
||||
}
|
||||
/* During the first kex, secret hash and session ID are equal. However, after
|
||||
* a key re-exchange, a new secret hash is calculated. This hash will not replace
|
||||
* but complement existing session id.
|
||||
*/
|
||||
if (!session->next_crypto->session_id) {
|
||||
session->next_crypto->session_id = malloc(session->next_crypto->digest_len);
|
||||
if (session->next_crypto->session_id == NULL) {
|
||||
ssh_set_error_oom(session);
|
||||
goto error;
|
||||
}
|
||||
memcpy(session->next_crypto->session_id, session->next_crypto->secret_hash,
|
||||
session->next_crypto->digest_len);
|
||||
}
|
||||
session->next_crypto->digest_len = SHA256_DIGEST_LENGTH;
|
||||
session->next_crypto->mac_type = SSH_MAC_SHA256;
|
||||
session->next_crypto->secret_hash = malloc(session->next_crypto->digest_len);
|
||||
if(session->next_crypto->secret_hash == NULL){
|
||||
ssh_set_error_oom(session);
|
||||
goto error;
|
||||
}
|
||||
sha256(buffer_get_rest(buf), buffer_get_rest_len(buf),
|
||||
session->next_crypto->secret_hash);
|
||||
break;
|
||||
}
|
||||
/* During the first kex, secret hash and session ID are equal. However, after
|
||||
* a key re-exchange, a new secret hash is calculated. This hash will not replace
|
||||
* but complement existing session id.
|
||||
*/
|
||||
if (!session->next_crypto->session_id){
|
||||
session->next_crypto->session_id = malloc(session->next_crypto->digest_len);
|
||||
if (session->next_crypto->session_id == NULL){
|
||||
ssh_set_error_oom(session);
|
||||
goto error;
|
||||
}
|
||||
memcpy(session->next_crypto->session_id, session->next_crypto->secret_hash,
|
||||
session->next_crypto->digest_len);
|
||||
}
|
||||
#ifdef DEBUG_CRYPTO
|
||||
printf("Session hash: \n");
|
||||
ssh_print_hexa("secret hash", session->next_crypto->secret_hash, session->next_crypto->digest_len);
|
||||
ssh_print_hexa("session id", session->next_crypto->session_id, session->next_crypto->digest_len);
|
||||
printf("Session hash: \n");
|
||||
ssh_print_hexa("secret hash", session->next_crypto->secret_hash, session->next_crypto->digest_len);
|
||||
ssh_print_hexa("session id", session->next_crypto->session_id, session->next_crypto->digest_len);
|
||||
#endif
|
||||
|
||||
rc = SSH_OK;
|
||||
rc = SSH_OK;
|
||||
error:
|
||||
ssh_buffer_free(buf);
|
||||
ssh_buffer_free(client_hash);
|
||||
ssh_buffer_free(server_hash);
|
||||
ssh_buffer_free(buf);
|
||||
ssh_buffer_free(client_hash);
|
||||
ssh_buffer_free(server_hash);
|
||||
|
||||
session->in_hashbuf = NULL;
|
||||
session->out_hashbuf = NULL;
|
||||
session->in_hashbuf = NULL;
|
||||
session->out_hashbuf = NULL;
|
||||
|
||||
ssh_string_free(str);
|
||||
ssh_string_free(num);
|
||||
ssh_string_free(str);
|
||||
ssh_string_free(num);
|
||||
|
||||
return rc;
|
||||
return rc;
|
||||
}
|
||||
|
||||
int hashbufout_add_cookie(ssh_session session) {
|
||||
|
||||
213
src/kex.c
213
src/kex.c
@@ -275,172 +275,87 @@ char *ssh_find_matching(const char *available_d, const char *preferred_d){
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/**
|
||||
* @internal
|
||||
* @brief returns whether the first client key exchange algorithm matches
|
||||
* the first server key exchange algorithm
|
||||
* @returns whether the first client key exchange algorithm matches
|
||||
* the first server key exchange algorithm
|
||||
*/
|
||||
static int is_first_kex_packet_follows_guess_wrong(const char *client_kex,
|
||||
const char *server_kex) {
|
||||
int is_wrong = 1;
|
||||
char **server_kex_tokens = NULL;
|
||||
char **client_kex_tokens = tokenize(client_kex);
|
||||
|
||||
if (client_kex_tokens == NULL) {
|
||||
goto out;
|
||||
}
|
||||
|
||||
if (client_kex_tokens[0] == NULL) {
|
||||
goto freeout;
|
||||
}
|
||||
|
||||
server_kex_tokens = tokenize(server_kex);
|
||||
if (server_kex_tokens == NULL) {
|
||||
goto freeout;
|
||||
}
|
||||
|
||||
is_wrong = (strcmp(client_kex_tokens[0], server_kex_tokens[0]) != 0);
|
||||
|
||||
SAFE_FREE(server_kex_tokens[0]);
|
||||
SAFE_FREE(server_kex_tokens);
|
||||
freeout:
|
||||
SAFE_FREE(client_kex_tokens[0]);
|
||||
SAFE_FREE(client_kex_tokens);
|
||||
out:
|
||||
return is_wrong;
|
||||
}
|
||||
|
||||
SSH_PACKET_CALLBACK(ssh_packet_kexinit){
|
||||
int i;
|
||||
int server_kex=session->server;
|
||||
ssh_string str = NULL;
|
||||
char *strings[KEX_METHODS_SIZE];
|
||||
int rc = SSH_ERROR;
|
||||
int server_kex=session->server;
|
||||
ssh_string str = NULL;
|
||||
char *strings[KEX_METHODS_SIZE];
|
||||
int i;
|
||||
|
||||
uint8_t first_kex_packet_follows = 0;
|
||||
uint32_t kexinit_reserved = 0;
|
||||
|
||||
(void)type;
|
||||
(void)user;
|
||||
|
||||
memset(strings, 0, sizeof(strings));
|
||||
if (session->session_state == SSH_SESSION_STATE_AUTHENTICATED){
|
||||
SSH_LOG(SSH_LOG_WARNING, "Other side initiating key re-exchange");
|
||||
} else if(session->session_state != SSH_SESSION_STATE_INITIAL_KEX){
|
||||
ssh_set_error(session,SSH_FATAL,"SSH_KEXINIT received in wrong state");
|
||||
(void)type;
|
||||
(void)user;
|
||||
memset(strings, 0, sizeof(strings));
|
||||
if (session->session_state == SSH_SESSION_STATE_AUTHENTICATED){
|
||||
SSH_LOG(SSH_LOG_WARNING, "Other side initiating key re-exchange");
|
||||
} else if(session->session_state != SSH_SESSION_STATE_INITIAL_KEX){
|
||||
ssh_set_error(session,SSH_FATAL,"SSH_KEXINIT received in wrong state");
|
||||
goto error;
|
||||
}
|
||||
if (server_kex) {
|
||||
if (buffer_get_data(packet,session->next_crypto->client_kex.cookie,16) != 16) {
|
||||
ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: no cookie in packet");
|
||||
goto error;
|
||||
}
|
||||
}
|
||||
|
||||
if (server_kex) {
|
||||
rc = buffer_get_data(packet,session->next_crypto->client_kex.cookie, 16);
|
||||
if (rc != 16) {
|
||||
ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: no cookie in packet");
|
||||
goto error;
|
||||
}
|
||||
|
||||
rc = hashbufin_add_cookie(session, session->next_crypto->client_kex.cookie);
|
||||
if (rc < 0) {
|
||||
ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: adding cookie failed");
|
||||
goto error;
|
||||
}
|
||||
} else {
|
||||
rc = buffer_get_data(packet,session->next_crypto->server_kex.cookie, 16);
|
||||
if (rc != 16) {
|
||||
ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: no cookie in packet");
|
||||
goto error;
|
||||
}
|
||||
|
||||
rc = hashbufin_add_cookie(session, session->next_crypto->server_kex.cookie);
|
||||
if (rc < 0) {
|
||||
ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: adding cookie failed");
|
||||
goto error;
|
||||
}
|
||||
}
|
||||
|
||||
for (i = 0; i < KEX_METHODS_SIZE; i++) {
|
||||
str = buffer_get_ssh_string(packet);
|
||||
if (str == NULL) {
|
||||
break;
|
||||
}
|
||||
|
||||
rc = buffer_add_ssh_string(session->in_hashbuf, str);
|
||||
if (rc < 0) {
|
||||
ssh_set_error(session, SSH_FATAL, "Error adding string in hash buffer");
|
||||
goto error;
|
||||
}
|
||||
|
||||
strings[i] = ssh_string_to_char(str);
|
||||
if (strings[i] == NULL) {
|
||||
ssh_set_error_oom(session);
|
||||
goto error;
|
||||
}
|
||||
ssh_string_free(str);
|
||||
str = NULL;
|
||||
}
|
||||
|
||||
/* copy the server kex info into an array of strings */
|
||||
if (server_kex) {
|
||||
for (i = 0; i < SSH_KEX_METHODS; i++) {
|
||||
session->next_crypto->client_kex.methods[i] = strings[i];
|
||||
}
|
||||
} else { /* client */
|
||||
for (i = 0; i < SSH_KEX_METHODS; i++) {
|
||||
session->next_crypto->server_kex.methods[i] = strings[i];
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Handle the two final fields for the KEXINIT message (RFC 4253 7.1):
|
||||
*
|
||||
* boolean first_kex_packet_follows
|
||||
* uint32 0 (reserved for future extension)
|
||||
*
|
||||
* Notably if clients set 'first_kex_packet_follows', it is expected
|
||||
* that its value is included when computing the session ID (see
|
||||
* 'make_sessionid').
|
||||
*/
|
||||
rc = buffer_get_u8(packet, &first_kex_packet_follows);
|
||||
if (rc != 1) {
|
||||
if (hashbufin_add_cookie(session, session->next_crypto->client_kex.cookie) < 0) {
|
||||
ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: adding cookie failed");
|
||||
goto error;
|
||||
}
|
||||
|
||||
rc = buffer_add_u8(session->in_hashbuf, first_kex_packet_follows);
|
||||
if (rc < 0) {
|
||||
}
|
||||
} else {
|
||||
if (buffer_get_data(packet,session->next_crypto->server_kex.cookie,16) != 16) {
|
||||
ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: no cookie in packet");
|
||||
goto error;
|
||||
}
|
||||
}
|
||||
|
||||
rc = buffer_add_u32(session->in_hashbuf, kexinit_reserved);
|
||||
if (rc < 0) {
|
||||
if (hashbufin_add_cookie(session, session->next_crypto->server_kex.cookie) < 0) {
|
||||
ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: adding cookie failed");
|
||||
goto error;
|
||||
}
|
||||
}
|
||||
|
||||
for (i = 0; i < KEX_METHODS_SIZE; i++) {
|
||||
str = buffer_get_ssh_string(packet);
|
||||
if (str == NULL) {
|
||||
break;
|
||||
}
|
||||
|
||||
/*
|
||||
* Remember whether 'first_kex_packet_follows' was set and the client
|
||||
* guess was wrong: in this case the next SSH_MSG_KEXDH_INIT message
|
||||
* must be ignored.
|
||||
*/
|
||||
if (server_kex && first_kex_packet_follows) {
|
||||
session->first_kex_follows_guess_wrong =
|
||||
is_first_kex_packet_follows_guess_wrong(session->next_crypto->client_kex.methods[SSH_KEX],
|
||||
session->next_crypto->server_kex.methods[SSH_KEX]);
|
||||
if (buffer_add_ssh_string(session->in_hashbuf, str) < 0) {
|
||||
ssh_set_error(session, SSH_FATAL, "Error adding string in hash buffer");
|
||||
goto error;
|
||||
}
|
||||
|
||||
session->session_state = SSH_SESSION_STATE_KEXINIT_RECEIVED;
|
||||
session->dh_handshake_state = DH_STATE_INIT;
|
||||
session->ssh_connection_callback(session);
|
||||
return SSH_PACKET_USED;
|
||||
|
||||
error:
|
||||
strings[i] = ssh_string_to_char(str);
|
||||
if (strings[i] == NULL) {
|
||||
ssh_set_error_oom(session);
|
||||
goto error;
|
||||
}
|
||||
ssh_string_free(str);
|
||||
str = NULL;
|
||||
}
|
||||
|
||||
/* copy the server kex info into an array of strings */
|
||||
if (server_kex) {
|
||||
for (i = 0; i < SSH_KEX_METHODS; i++) {
|
||||
SAFE_FREE(strings[i]);
|
||||
session->next_crypto->client_kex.methods[i] = strings[i];
|
||||
}
|
||||
} else { /* client */
|
||||
for (i = 0; i < SSH_KEX_METHODS; i++) {
|
||||
session->next_crypto->server_kex.methods[i] = strings[i];
|
||||
}
|
||||
}
|
||||
|
||||
session->session_state = SSH_SESSION_STATE_ERROR;
|
||||
session->session_state=SSH_SESSION_STATE_KEXINIT_RECEIVED;
|
||||
session->dh_handshake_state=DH_STATE_INIT;
|
||||
session->ssh_connection_callback(session);
|
||||
return SSH_PACKET_USED;
|
||||
error:
|
||||
ssh_string_free(str);
|
||||
for (i = 0; i < SSH_KEX_METHODS; i++) {
|
||||
SAFE_FREE(strings[i]);
|
||||
}
|
||||
|
||||
return SSH_PACKET_USED;
|
||||
session->session_state = SSH_SESSION_STATE_ERROR;
|
||||
|
||||
return SSH_PACKET_USED;
|
||||
}
|
||||
|
||||
void ssh_list_kex(struct ssh_kex_struct *kex) {
|
||||
|
||||
@@ -174,15 +174,6 @@ SSH_PACKET_CALLBACK(ssh_packet_kexdh_init){
|
||||
SSH_LOG(SSH_LOG_RARE,"Invalid state for SSH_MSG_KEXDH_INIT");
|
||||
goto error;
|
||||
}
|
||||
|
||||
/* If first_kex_packet_follows guess was wrong, ignore this message. */
|
||||
if (session->first_kex_follows_guess_wrong != 0) {
|
||||
SSH_LOG(SSH_LOG_RARE, "first_kex_packet_follows guess was wrong, "
|
||||
"ignoring first SSH_MSG_KEXDH_INIT message");
|
||||
session->first_kex_follows_guess_wrong = 0;
|
||||
goto error;
|
||||
}
|
||||
|
||||
switch(session->next_crypto->kex_type){
|
||||
case SSH_KEX_DH_GROUP1_SHA1:
|
||||
case SSH_KEX_DH_GROUP14_SHA1:
|
||||
|
||||
Reference in New Issue
Block a user