static void send_client_banner(int connection_out, int minor1) { /* Send our own protocol version identification. */ if (compat20) { #ifndef WIN32_FIXME xasprintf(&client_version_string, "SSH-%d.%d-%.100s\r\n", PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2, SSH_VERSION); #else #ifdef WIN32_VS xasprintf(&client_version_string, "SSH-%d.%d-%.100sp1 Microsoft Win32 port with VS %s\r\n", PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2, SSH_VERSION, __DATE__ ); #else xasprintf(&client_version_string, "SSH-%d.%d-%.100sp1 Microsoft Win32 port %s\r\n", PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2, SSH_VERSION, __DATE__ ); #endif #endif } else { xasprintf(&client_version_string, "SSH-%d.%d-%.100s\n", PROTOCOL_MAJOR_1, minor1, SSH_VERSION); } if (roaming_atomicio(vwrite, connection_out, client_version_string, strlen(client_version_string)) != strlen(client_version_string)) fatal("write: %.100s", strerror(errno)); chop(client_version_string); debug("Local version string %.100s", client_version_string); }
static void send_client_banner(int connection_out, int minor1) { /* Send our own protocol version identification. */ xasprintf(&client_version_string, "SSH-%d.%d-%.100s%s%s%s", compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, compat20 ? PROTOCOL_MINOR_2 : minor1, SSH_VERSION, *options.version_addendum == '\0' ? "" : " ", options.version_addendum, compat20 ? "\r\n" : "\n"); if (roaming_atomicio(vwrite, connection_out, client_version_string, strlen(client_version_string)) != strlen(client_version_string)) fatal("write: %.100s", strerror(errno)); chop(client_version_string); debug("Local version string %.100s", client_version_string); }
static void send_client_banner(int connection_out, int minor1) { /* Send our own protocol version identification. */ if (compat20) { xasprintf(&client_version_string, "SSH-%d.%d-%.100s\r\n", PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2, SSH_VERSION); } else { xasprintf(&client_version_string, "SSH-%d.%d-%.100s\n", PROTOCOL_MAJOR_1, minor1, SSH_VERSION); } if (roaming_atomicio(vwrite, connection_out, client_version_string, strlen(client_version_string)) != strlen(client_version_string)) fatal("write: %.100s", strerror(errno)); chop(client_version_string); debug("Local version string %.100s", client_version_string); }
/* * Waits for the server identification string, and sends our own * identification string. */ void ssh_exchange_identification(int timeout_ms) { char buf[256], remote_version[256]; /* must be same size! */ int remote_major, remote_minor, mismatch; int connection_in = packet_get_connection_in(); int connection_out = packet_get_connection_out(); int minor1 = PROTOCOL_MINOR_1, client_banner_sent = 0; u_int i, n; size_t len; int fdsetsz, remaining, rc; struct timeval t_start, t_remaining; fd_set *fdset; fdsetsz = howmany(connection_in + 1, NFDBITS) * sizeof(fd_mask); fdset = xcalloc(1, fdsetsz); /* * If we are SSH2-only then we can send the banner immediately and * save a round-trip. */ if (options.protocol == SSH_PROTO_2) { enable_compat20(); send_client_banner(connection_out, 0); client_banner_sent = 1; } /* Read other side's version identification. */ remaining = timeout_ms; for (n = 0;;) { for (i = 0; i < sizeof(buf) - 1; i++) { if (timeout_ms > 0) { gettimeofday(&t_start, NULL); ms_to_timeval(&t_remaining, remaining); FD_SET(connection_in, fdset); rc = select(connection_in + 1, fdset, NULL, fdset, &t_remaining); ms_subtract_diff(&t_start, &remaining); if (rc == 0 || remaining <= 0) fatal("Connection timed out during " "banner exchange"); if (rc == -1) { if (errno == EINTR) continue; fatal("ssh_exchange_identification: " "select: %s", strerror(errno)); } } len = roaming_atomicio(read, connection_in, &buf[i], 1); if (len != 1 && errno == EPIPE) fatal("ssh_exchange_identification: " "Connection closed by remote host"); else if (len != 1) fatal("ssh_exchange_identification: " "read: %.100s", strerror(errno)); if (buf[i] == '\r') { buf[i] = '\n'; buf[i + 1] = 0; continue; /**XXX wait for \n */ } if (buf[i] == '\n') { buf[i + 1] = 0; break; } if (++n > 65536) fatal("ssh_exchange_identification: " "No banner received"); } buf[sizeof(buf) - 1] = 0; if (strncmp(buf, "SSH-", 4) == 0) break; debug("ssh_exchange_identification: %s", buf); } server_version_string = xstrdup(buf); free(fdset); /* * Check that the versions match. In future this might accept * several versions and set appropriate flags to handle them. */ if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n", &remote_major, &remote_minor, remote_version) != 3) fatal("Bad remote protocol version identification: '%.100s'", buf); debug("Remote protocol version %d.%d, remote software version %.100s", remote_major, remote_minor, remote_version); active_state->compat = compat_datafellows(remote_version); mismatch = 0; switch (remote_major) { case 1: if (remote_minor == 99 && (options.protocol & SSH_PROTO_2) && !(options.protocol & SSH_PROTO_1_PREFERRED)) { enable_compat20(); break; } if (!(options.protocol & SSH_PROTO_1)) { mismatch = 1; break; } if (remote_minor < 3) { fatal("Remote machine has too old SSH software version."); } else if (remote_minor == 3 || remote_minor == 4) { /* We speak 1.3, too. */ enable_compat13(); minor1 = 3; if (options.forward_agent) { logit("Agent forwarding disabled for protocol 1.3"); options.forward_agent = 0; } } break; case 2: if (options.protocol & SSH_PROTO_2) { enable_compat20(); break; } /* FALLTHROUGH */ default: mismatch = 1; break; } if (mismatch) fatal("Protocol major versions differ: %d vs. %d", (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, remote_major); if ((datafellows & SSH_BUG_DERIVEKEY) != 0) fatal("Server version \"%.100s\" uses unsafe key agreement; " "refusing connection", remote_version); if ((datafellows & SSH_BUG_RSASIGMD5) != 0) logit("Server version \"%.100s\" uses unsafe RSA signature " "scheme; disabling use of RSA keys", remote_version); if (!client_banner_sent) send_client_banner(connection_out, minor1); chop(server_version_string); }
/* * Waits for the server identification string, and sends our own * identification string. */ void ssh_exchange_identification(struct ssh *ssh, int timeout_ms) { char buf[256], remote_version[256]; /* must be same size! */ int remote_major, remote_minor, mismatch; int connection_in = ssh_packet_get_connection_in(ssh); int connection_out = ssh_packet_get_connection_out(ssh); int minor1 = PROTOCOL_MINOR_1; u_int i, n; size_t len; int fdsetsz, remaining, rc; struct timeval t_start, t_remaining; fd_set *fdset; fdsetsz = howmany(connection_in + 1, NFDBITS) * sizeof(fd_mask); fdset = xcalloc(1, fdsetsz); /* Read other side's version identification. */ remaining = timeout_ms; for (n = 0;;) { for (i = 0; i < sizeof(buf) - 1; i++) { if (timeout_ms > 0) { gettimeofday(&t_start, NULL); ms_to_timeval(&t_remaining, remaining); FD_SET(connection_in, fdset); rc = select(connection_in + 1, fdset, NULL, fdset, &t_remaining); ms_subtract_diff(&t_start, &remaining); if (rc == 0 || remaining <= 0) fatal("Connection timed out during " "banner exchange"); if (rc == -1) { if (errno == EINTR) continue; fatal("ssh_exchange_identification: " "select: %s", strerror(errno)); } } len = roaming_atomicio(read, connection_in, &buf[i], 1); if (len != 1 && errno == EPIPE) fatal("ssh_exchange_identification: " "Connection closed by remote host"); else if (len != 1) fatal("ssh_exchange_identification: " "read: %.100s", strerror(errno)); if (buf[i] == '\r') { buf[i] = '\n'; buf[i + 1] = 0; continue; /**XXX wait for \n */ } if (buf[i] == '\n') { buf[i + 1] = 0; break; } if (++n > 65536) fatal("ssh_exchange_identification: " "No banner received"); } buf[sizeof(buf) - 1] = 0; if (strncmp(buf, "SSH-", 4) == 0) break; debug("ssh_exchange_identification: %s", buf); } server_version_string = xstrdup(buf); xfree(fdset); /* * Check that the versions match. In future this might accept * several versions and set appropriate flags to handle them. */ if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n", &remote_major, &remote_minor, remote_version) != 3) fatal("Bad remote protocol version identification: '%.100s'", buf); debug("Remote protocol version %d.%d, remote software version %.100s", remote_major, remote_minor, remote_version); ssh->compat = compat_datafellows(remote_version); mismatch = 0; switch (remote_major) { case 1: if (remote_minor == 99 && (options.protocol & SSH_PROTO_2) && !(options.protocol & SSH_PROTO_1_PREFERRED)) { enable_compat20(); break; } if (!(options.protocol & SSH_PROTO_1)) { mismatch = 1; break; } if (remote_minor < 3) { fatal("Remote machine has too old SSH software version."); } else if (remote_minor == 3 || remote_minor == 4) { /* We speak 1.3, too. */ enable_compat13(); minor1 = 3; if (options.forward_agent) { logit("Agent forwarding disabled for protocol 1.3"); options.forward_agent = 0; } } break; case 2: if (options.protocol & SSH_PROTO_2) { enable_compat20(); break; } /* FALLTHROUGH */ default: mismatch = 1; break; } if (mismatch) fatal("Protocol major versions differ: %d vs. %d", (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, remote_major); /* Send our own protocol version identification. */ snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s%s", compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, compat20 ? PROTOCOL_MINOR_2 : minor1, SSH_VERSION, compat20 ? "\r\n" : "\n"); if (roaming_atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf)) fatal("write: %.100s", strerror(errno)); client_version_string = xstrdup(buf); chop(client_version_string); chop(server_version_string); debug("Local version string %.100s", client_version_string); }