From 95def09838fc61b37b6ea7cd5c234a465b4b129b Mon Sep 17 00:00:00 2001 From: Damien Miller Date: Thu, 25 Nov 1999 00:26:21 +1100 Subject: - Merged very large OpenBSD source code reformat - OpenBSD CVS updates - [channels.c cipher.c compat.c log-client.c scp.c serverloop.c] [ssh.h sshd.8 sshd.c] syslog changes: * Unified Logmessage for all auth-types, for success and for failed * Standard connections get only ONE line in the LOG when level==LOG: Auth-attempts are logged only, if authentication is: a) successfull or b) with passwd or c) we had more than AUTH_FAIL_LOG failues * many log() became verbose() * old behaviour with level=VERBOSE - [readconf.c readconf.h ssh.1 ssh.h sshconnect.c sshd.c] tranfer s/key challenge/response data in SSH_SMSG_AUTH_TIS_CHALLENGE messages. allows use of s/key in windows (ttssh, securecrt) and ssh-1.2.27 clients without 'ssh -v', ok: niels@ - [sshd.8] -V, for fallback to openssh in SSH2 compatibility mode - [sshd.c] fix sigchld race; cjc5@po.cwru.edu --- packet.c | 859 +++++++++++++++++++++++++++++++-------------------------------- 1 file changed, 419 insertions(+), 440 deletions(-) (limited to 'packet.c') diff --git a/packet.c b/packet.c index 74bb38230..0e60dd5ec 100644 --- a/packet.c +++ b/packet.c @@ -1,21 +1,21 @@ /* - -packet.c - -Author: Tatu Ylonen - -Copyright (c) 1995 Tatu Ylonen , Espoo, Finland - All rights reserved - -Created: Sat Mar 18 02:40:40 1995 ylo - -This file contains code implementing the packet protocol and communication -with the other side. This same code is used both on client and server side. - -*/ + * + * packet.c + * + * Author: Tatu Ylonen + * + * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland + * All rights reserved + * + * Created: Sat Mar 18 02:40:40 1995 ylo + * + * This file contains code implementing the packet protocol and communication + * with the other side. This same code is used both on client and server side. + * + */ #include "includes.h" -RCSID("$Id: packet.c,v 1.4 1999/11/21 02:23:53 damien Exp $"); +RCSID("$Id: packet.c,v 1.5 1999/11/24 13:26:22 damien Exp $"); #include "xmalloc.h" #include "buffer.h" @@ -45,7 +45,8 @@ static unsigned int remote_protocol_flags = 0; /* Encryption context for receiving data. This is only used for decryption. */ static CipherContext receive_context; -/* Encryption coontext for sending data. This is only used for encryption. */ + +/* Encryption context for sending data. This is only used for encryption. */ static CipherContext send_context; /* Buffer for raw input data from the socket. */ @@ -81,22 +82,20 @@ static int interactive_mode = 0; void packet_set_connection(int fd_in, int fd_out) { - connection_in = fd_in; - connection_out = fd_out; - cipher_type = SSH_CIPHER_NONE; - cipher_set_key(&send_context, SSH_CIPHER_NONE, (unsigned char *)"", 0, 1); - cipher_set_key(&receive_context, SSH_CIPHER_NONE, (unsigned char *)"", 0, 0); - if (!initialized) - { - initialized = 1; - buffer_init(&input); - buffer_init(&output); - buffer_init(&outgoing_packet); - buffer_init(&incoming_packet); - } - - /* Kludge: arrange the close function to be called from fatal(). */ - fatal_add_cleanup((void (*)(void *))packet_close, NULL); + connection_in = fd_in; + connection_out = fd_out; + cipher_type = SSH_CIPHER_NONE; + cipher_set_key(&send_context, SSH_CIPHER_NONE, (unsigned char *) "", 0, 1); + cipher_set_key(&receive_context, SSH_CIPHER_NONE, (unsigned char *) "", 0, 0); + if (!initialized) { + initialized = 1; + buffer_init(&input); + buffer_init(&output); + buffer_init(&outgoing_packet); + buffer_init(&incoming_packet); + } + /* Kludge: arrange the close function to be called from fatal(). */ + fatal_add_cleanup((void (*) (void *)) packet_close, NULL); } /* Sets the connection into non-blocking mode. */ @@ -104,15 +103,14 @@ packet_set_connection(int fd_in, int fd_out) void packet_set_nonblocking() { - /* Set the socket into non-blocking mode. */ - if (fcntl(connection_in, F_SETFL, O_NONBLOCK) < 0) - error("fcntl O_NONBLOCK: %.100s", strerror(errno)); + /* Set the socket into non-blocking mode. */ + if (fcntl(connection_in, F_SETFL, O_NONBLOCK) < 0) + error("fcntl O_NONBLOCK: %.100s", strerror(errno)); - if (connection_out != connection_in) - { - if (fcntl(connection_out, F_SETFL, O_NONBLOCK) < 0) - error("fcntl O_NONBLOCK: %.100s", strerror(errno)); - } + if (connection_out != connection_in) { + if (fcntl(connection_out, F_SETFL, O_NONBLOCK) < 0) + error("fcntl O_NONBLOCK: %.100s", strerror(errno)); + } } /* Returns the socket used for reading. */ @@ -120,7 +118,7 @@ packet_set_nonblocking() int packet_get_connection_in() { - return connection_in; + return connection_in; } /* Returns the descriptor used for writing. */ @@ -128,7 +126,7 @@ packet_get_connection_in() int packet_get_connection_out() { - return connection_out; + return connection_out; } /* Closes the connection and clears and frees internal data structures. */ @@ -136,28 +134,24 @@ packet_get_connection_out() void packet_close() { - if (!initialized) - return; - initialized = 0; - if (connection_in == connection_out) - { - shutdown(connection_out, SHUT_RDWR); - close(connection_out); - } - else - { - close(connection_in); - close(connection_out); - } - buffer_free(&input); - buffer_free(&output); - buffer_free(&outgoing_packet); - buffer_free(&incoming_packet); - if (packet_compression) - { - buffer_free(&compression_buffer); - buffer_compress_uninit(); - } + if (!initialized) + return; + initialized = 0; + if (connection_in == connection_out) { + shutdown(connection_out, SHUT_RDWR); + close(connection_out); + } else { + close(connection_in); + close(connection_out); + } + buffer_free(&input); + buffer_free(&output); + buffer_free(&outgoing_packet); + buffer_free(&incoming_packet); + if (packet_compression) { + buffer_free(&compression_buffer); + buffer_compress_uninit(); + } } /* Sets remote side protocol flags. */ @@ -165,8 +159,8 @@ packet_close() void packet_set_protocol_flags(unsigned int protocol_flags) { - remote_protocol_flags = protocol_flags; - channel_set_options((protocol_flags & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) != 0); + remote_protocol_flags = protocol_flags; + channel_set_options((protocol_flags & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) != 0); } /* Returns the remote protocol flags set earlier by the above function. */ @@ -174,63 +168,60 @@ packet_set_protocol_flags(unsigned int protocol_flags) unsigned int packet_get_protocol_flags() { - return remote_protocol_flags; + return remote_protocol_flags; } -/* Starts packet compression from the next packet on in both directions. +/* Starts packet compression from the next packet on in both directions. Level is compression level 1 (fastest) - 9 (slow, best) as in gzip. */ void packet_start_compression(int level) { - if (packet_compression) - fatal("Compression already enabled."); - packet_compression = 1; - buffer_init(&compression_buffer); - buffer_compress_init(level); + if (packet_compression) + fatal("Compression already enabled."); + packet_compression = 1; + buffer_init(&compression_buffer); + buffer_compress_init(level); } /* Encrypts the given number of bytes, copying from src to dest. bytes is known to be a multiple of 8. */ void -packet_encrypt(CipherContext *cc, void *dest, void *src, +packet_encrypt(CipherContext * cc, void *dest, void *src, unsigned int bytes) { - cipher_encrypt(cc, dest, src, bytes); + cipher_encrypt(cc, dest, src, bytes); } /* Decrypts the given number of bytes, copying from src to dest. bytes is known to be a multiple of 8. */ void -packet_decrypt(CipherContext *cc, void *dest, void *src, +packet_decrypt(CipherContext * cc, void *dest, void *src, unsigned int bytes) { - int i; - - if ((bytes % 8) != 0) - fatal("packet_decrypt: bad ciphertext length %d", bytes); - - /* - Cryptographic attack detector for ssh - Modifications for packet.c - (C)1998 CORE-SDI, Buenos Aires Argentina - Ariel Futoransky(futo@core-sdi.com) - */ - switch (cc->type) - { - case SSH_CIPHER_NONE: - i = DEATTACK_OK; - break; - default: - i = detect_attack(src, bytes, NULL); - break; - } - - if (i == DEATTACK_DETECTED) - packet_disconnect("crc32 compensation attack: network attack detected"); - - cipher_decrypt(cc, dest, src, bytes); + int i; + + if ((bytes % 8) != 0) + fatal("packet_decrypt: bad ciphertext length %d", bytes); + + /* Cryptographic attack detector for ssh - Modifications for packet.c + (C)1998 CORE-SDI, Buenos Aires Argentina Ariel Futoransky(futo@core-sdi.com) */ + + switch (cc->type) { + case SSH_CIPHER_NONE: + i = DEATTACK_OK; + break; + default: + i = detect_attack(src, bytes, NULL); + break; + } + + if (i == DEATTACK_DETECTED) + packet_disconnect("crc32 compensation attack: network attack detected"); + + cipher_decrypt(cc, dest, src, bytes); } /* Causes any further packets to be encrypted using the given key. The same @@ -241,9 +232,9 @@ void packet_set_encryption_key(const unsigned char *key, unsigned int keylen, int cipher) { - /* All other ciphers use the same key in both directions for now. */ - cipher_set_key(&receive_context, cipher, key, keylen, 0); - cipher_set_key(&send_context, cipher, key, keylen, 1); + /* All other ciphers use the same key in both directions for now. */ + cipher_set_key(&receive_context, cipher, key, keylen, 0); + cipher_set_key(&send_context, cipher, key, keylen, 1); } /* Starts constructing a packet to send. */ @@ -251,12 +242,12 @@ packet_set_encryption_key(const unsigned char *key, unsigned int keylen, void packet_start(int type) { - char buf[9]; + char buf[9]; - buffer_clear(&outgoing_packet); - memset(buf, 0, 8); - buf[8] = type; - buffer_append(&outgoing_packet, buf, 9); + buffer_clear(&outgoing_packet); + memset(buf, 0, 8); + buf[8] = type; + buffer_append(&outgoing_packet, buf, 9); } /* Appends a character to the packet data. */ @@ -264,8 +255,8 @@ packet_start(int type) void packet_put_char(int value) { - char ch = value; - buffer_append(&outgoing_packet, &ch, 1); + char ch = value; + buffer_append(&outgoing_packet, &ch, 1); } /* Appends an integer to the packet data. */ @@ -273,7 +264,7 @@ packet_put_char(int value) void packet_put_int(unsigned int value) { - buffer_put_int(&outgoing_packet, value); + buffer_put_int(&outgoing_packet, value); } /* Appends a string to packet data. */ @@ -281,84 +272,85 @@ packet_put_int(unsigned int value) void packet_put_string(const char *buf, unsigned int len) { - buffer_put_string(&outgoing_packet, buf, len); + buffer_put_string(&outgoing_packet, buf, len); } /* Appends an arbitrary precision integer to packet data. */ void -packet_put_bignum(BIGNUM *value) +packet_put_bignum(BIGNUM * value) { - buffer_put_bignum(&outgoing_packet, value); + buffer_put_bignum(&outgoing_packet, value); } /* Finalizes and sends the packet. If the encryption key has been set, encrypts the packet before sending. */ - + void packet_send() { - char buf[8], *cp; - int i, padding, len; - unsigned int checksum; - u_int32_t rand = 0; - - /* If using packet compression, compress the payload of the outgoing - packet. */ - if (packet_compression) - { - buffer_clear(&compression_buffer); - buffer_consume(&outgoing_packet, 8); /* Skip padding. */ - buffer_append(&compression_buffer, "\0\0\0\0\0\0\0\0", 8); /* padding */ - buffer_compress(&outgoing_packet, &compression_buffer); - buffer_clear(&outgoing_packet); - buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer), - buffer_len(&compression_buffer)); - } - - /* Compute packet length without padding (add checksum, remove padding). */ - len = buffer_len(&outgoing_packet) + 4 - 8; - - /* Insert padding. */ - padding = 8 - len % 8; - if (cipher_type != SSH_CIPHER_NONE) - { - cp = buffer_ptr(&outgoing_packet); - for (i = 0; i < padding; i++) { - if (i % 4 == 0) - rand = arc4random(); - cp[7 - i] = rand & 0xff; - rand >>= 8; - } - } - buffer_consume(&outgoing_packet, 8 - padding); - - /* Add check bytes. */ - checksum = crc32((unsigned char *)buffer_ptr(&outgoing_packet), - buffer_len(&outgoing_packet)); - PUT_32BIT(buf, checksum); - buffer_append(&outgoing_packet, buf, 4); + char buf[8], *cp; + int i, padding, len; + unsigned int checksum; + u_int32_t rand = 0; + + /* If using packet compression, compress the payload of the + outgoing packet. */ + if (packet_compression) { + buffer_clear(&compression_buffer); + /* Skip padding. */ + buffer_consume(&outgoing_packet, 8); + /* padding */ + buffer_append(&compression_buffer, "\0\0\0\0\0\0\0\0", 8); + buffer_compress(&outgoing_packet, &compression_buffer); + buffer_clear(&outgoing_packet); + buffer_append(&outgoing_packet, buffer_ptr(&compression_buffer), + buffer_len(&compression_buffer)); + } + /* Compute packet length without padding (add checksum, remove padding). */ + len = buffer_len(&outgoing_packet) + 4 - 8; + + /* Insert padding. */ + padding = 8 - len % 8; + if (cipher_type != SSH_CIPHER_NONE) { + cp = buffer_ptr(&outgoing_packet); + for (i = 0; i < padding; i++) { + if (i % 4 == 0) + rand = arc4random(); + cp[7 - i] = rand & 0xff; + rand >>= 8; + } + } + buffer_consume(&outgoing_packet, 8 - padding); + + /* Add check bytes. */ + checksum = crc32((unsigned char *) buffer_ptr(&outgoing_packet), + buffer_len(&outgoing_packet)); + PUT_32BIT(buf, checksum); + buffer_append(&outgoing_packet, buf, 4); #ifdef PACKET_DEBUG - fprintf(stderr, "packet_send plain: "); - buffer_dump(&outgoing_packet); + fprintf(stderr, "packet_send plain: "); + buffer_dump(&outgoing_packet); #endif - /* Append to output. */ - PUT_32BIT(buf, len); - buffer_append(&output, buf, 4); - buffer_append_space(&output, &cp, buffer_len(&outgoing_packet)); - packet_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet), - buffer_len(&outgoing_packet)); - + /* Append to output. */ + PUT_32BIT(buf, len); + buffer_append(&output, buf, 4); + buffer_append_space(&output, &cp, buffer_len(&outgoing_packet)); + packet_encrypt(&send_context, cp, buffer_ptr(&outgoing_packet), + buffer_len(&outgoing_packet)); + #ifdef PACKET_DEBUG - fprintf(stderr, "encrypted: "); buffer_dump(&output); + fprintf(stderr, "encrypted: "); + buffer_dump(&output); #endif - buffer_clear(&outgoing_packet); + buffer_clear(&outgoing_packet); - /* Note that the packet is now only buffered in output. It won\'t be - actually sent until packet_write_wait or packet_write_poll is called. */ + /* Note that the packet is now only buffered in output. It won\'t + be actually sent until packet_write_wait or packet_write_poll + is called. */ } /* Waits until a packet has been received, and returns its type. Note that @@ -368,42 +360,41 @@ packet_send() int packet_read(int *payload_len_ptr) { - int type, len; - fd_set set; - char buf[8192]; - - /* Since we are blocking, ensure that all written packets have been sent. */ - packet_write_wait(); - - /* Stay in the loop until we have received a complete packet. */ - for (;;) - { - /* Try to read a packet from the buffer. */ - type = packet_read_poll(payload_len_ptr); - if (type == SSH_SMSG_SUCCESS - || type == SSH_SMSG_FAILURE - || type == SSH_CMSG_EOF - || type == SSH_CMSG_EXIT_CONFIRMATION) - packet_integrity_check(*payload_len_ptr, 0, type); - /* If we got a packet, return it. */ - if (type != SSH_MSG_NONE) - return type; - /* Otherwise, wait for some data to arrive, add it to the buffer, - and try again. */ - FD_ZERO(&set); - FD_SET(connection_in, &set); - /* Wait for some data to arrive. */ - select(connection_in + 1, &set, NULL, NULL, NULL); - /* Read data from the socket. */ - len = read(connection_in, buf, sizeof(buf)); - if (len == 0) - fatal("Connection closed by remote host."); - if (len < 0) - fatal("Read from socket failed: %.100s", strerror(errno)); - /* Append it to the buffer. */ - packet_process_incoming(buf, len); - } - /*NOTREACHED*/ + int type, len; + fd_set set; + char buf[8192]; + + /* Since we are blocking, ensure that all written packets have been sent. */ + packet_write_wait(); + + /* Stay in the loop until we have received a complete packet. */ + for (;;) { + /* Try to read a packet from the buffer. */ + type = packet_read_poll(payload_len_ptr); + if (type == SSH_SMSG_SUCCESS + || type == SSH_SMSG_FAILURE + || type == SSH_CMSG_EOF + || type == SSH_CMSG_EXIT_CONFIRMATION) + packet_integrity_check(*payload_len_ptr, 0, type); + /* If we got a packet, return it. */ + if (type != SSH_MSG_NONE) + return type; + /* Otherwise, wait for some data to arrive, add it to the + buffer, and try again. */ + FD_ZERO(&set); + FD_SET(connection_in, &set); + /* Wait for some data to arrive. */ + select(connection_in + 1, &set, NULL, NULL, NULL); + /* Read data from the socket. */ + len = read(connection_in, buf, sizeof(buf)); + if (len == 0) + fatal("Connection closed by %.200s", get_remote_ipaddr()); + if (len < 0) + fatal("Read from socket failed: %.100s", strerror(errno)); + /* Append it to the buffer. */ + packet_process_incoming(buf, len); + } + /* NOTREACHED */ } /* Waits until a packet has been received, verifies that its type matches @@ -412,131 +403,126 @@ packet_read(int *payload_len_ptr) void packet_read_expect(int *payload_len_ptr, int expected_type) { - int type; + int type; - type = packet_read(payload_len_ptr); - if (type != expected_type) - packet_disconnect("Protocol error: expected packet type %d, got %d", - expected_type, type); + type = packet_read(payload_len_ptr); + if (type != expected_type) + packet_disconnect("Protocol error: expected packet type %d, got %d", + expected_type, type); } /* Checks if a full packet is available in the data received so far via - packet_process_incoming. If so, reads the packet; otherwise returns - SSH_MSG_NONE. This does not wait for data from the connection. - - SSH_MSG_DISCONNECT is handled specially here. Also, - SSH_MSG_IGNORE messages are skipped by this function and are never returned - to higher levels. - - The returned payload_len does include space consumed by: - Packet length - Padding - Packet type - Check bytes - - - */ + * packet_process_incoming. If so, reads the packet; otherwise returns + * SSH_MSG_NONE. This does not wait for data from the connection. + * + * SSH_MSG_DISCONNECT is handled specially here. Also, + * SSH_MSG_IGNORE messages are skipped by this function and are never returned + * to higher levels. + * + * The returned payload_len does include space consumed by: + * Packet length + * Padding + * Packet type + * Check bytes + */ int packet_read_poll(int *payload_len_ptr) { - unsigned int len, padded_len; - unsigned char *ucp; - char buf[8], *cp; - unsigned int checksum, stored_checksum; - - restart: - - /* Check if input size is less than minimum packet size. */ - if (buffer_len(&input) < 4 + 8) - return SSH_MSG_NONE; - /* Get length of incoming packet. */ - ucp = (unsigned char *)buffer_ptr(&input); - len = GET_32BIT(ucp); - if (len < 1 + 2 + 2 || len > 256*1024) - packet_disconnect("Bad packet length %d.", len); - padded_len = (len + 8) & ~7; - - /* Check if the packet has been entirely received. */ - if (buffer_len(&input) < 4 + padded_len) - return SSH_MSG_NONE; - - /* The entire packet is in buffer. */ - - /* Consume packet length. */ - buffer_consume(&input, 4); - - /* Copy data to incoming_packet. */ - buffer_clear(&incoming_packet); - buffer_append_space(&incoming_packet, &cp, padded_len); - packet_decrypt(&receive_context, cp, buffer_ptr(&input), padded_len); - buffer_consume(&input, padded_len); + unsigned int len, padded_len; + unsigned char *ucp; + char buf[8], *cp; + unsigned int checksum, stored_checksum; + +restart: + + /* Check if input size is less than minimum packet size. */ + if (buffer_len(&input) < 4 + 8) + return SSH_MSG_NONE; + /* Get length of incoming packet. */ + ucp = (unsigned char *) buffer_ptr(&input); + len = GET_32BIT(ucp); + if (len < 1 + 2 + 2 || len > 256 * 1024) + packet_disconnect("Bad packet length %d.", len); + padded_len = (len + 8) & ~7; + + /* Check if the packet has been entirely received. */ + if (buffer_len(&input) < 4 + padded_len) + return SSH_MSG_NONE; + + /* The entire packet is in buffer. */ + + /* Consume packet length. */ + buffer_consume(&input, 4); + + /* Copy data to incoming_packet. */ + buffer_clear(&incoming_packet); + buffer_append_space(&incoming_packet, &cp, padded_len); + packet_decrypt(&receive_context, cp, buffer_ptr(&input), padded_len); + buffer_consume(&input, padded_len); #ifdef PACKET_DEBUG - fprintf(stderr, "read_poll plain: "); buffer_dump(&incoming_packet); + fprintf(stderr, "read_poll plain: "); + buffer_dump(&incoming_packet); #endif - - /* Compute packet checksum. */ - checksum = crc32((unsigned char *)buffer_ptr(&incoming_packet), - buffer_len(&incoming_packet) - 4); - - /* Skip padding. */ - buffer_consume(&incoming_packet, 8 - len % 8); - - /* Test check bytes. */ - - if (len != buffer_len(&incoming_packet)) - packet_disconnect("packet_read_poll: len %d != buffer_len %d.", - len, buffer_len(&incoming_packet)); - - ucp = (unsigned char *)buffer_ptr(&incoming_packet) + len - 4; - stored_checksum = GET_32BIT(ucp); - if (checksum != stored_checksum) - packet_disconnect("Corrupted check bytes on input."); - buffer_consume_end(&incoming_packet, 4); - - /* If using packet compression, decompress the packet. */ - if (packet_compression) - { - buffer_clear(&compression_buffer); - buffer_uncompress(&incoming_packet, &compression_buffer); - buffer_clear(&incoming_packet); - buffer_append(&incoming_packet, buffer_ptr(&compression_buffer), - buffer_len(&compression_buffer)); - } - - /* Get packet type. */ - buffer_get(&incoming_packet, &buf[0], 1); - - /* Return length of payload (without type field). */ - *payload_len_ptr = buffer_len(&incoming_packet); - - /* Handle disconnect message. */ - if ((unsigned char)buf[0] == SSH_MSG_DISCONNECT) - fatal("%.900s", packet_get_string(NULL)); - - /* Ignore ignore messages. */ - if ((unsigned char)buf[0] == SSH_MSG_IGNORE) - goto restart; - - /* Send debug messages as debugging output. */ - if ((unsigned char)buf[0] == SSH_MSG_DEBUG) - { - debug("Remote: %.900s", packet_get_string(NULL)); - goto restart; - } - - /* Return type. */ - return (unsigned char)buf[0]; -} - + + /* Compute packet checksum. */ + checksum = crc32((unsigned char *) buffer_ptr(&incoming_packet), + buffer_len(&incoming_packet) - 4); + + /* Skip padding. */ + buffer_consume(&incoming_packet, 8 - len % 8); + + /* Test check bytes. */ + + if (len != buffer_len(&incoming_packet)) + packet_disconnect("packet_read_poll: len %d != buffer_len %d.", + len, buffer_len(&incoming_packet)); + + ucp = (unsigned char *) buffer_ptr(&incoming_packet) + len - 4; + stored_checksum = GET_32BIT(ucp); + if (checksum != stored_checksum) + packet_disconnect("Corrupted check bytes on input."); + buffer_consume_end(&incoming_packet, 4); + + /* If using packet compression, decompress the packet. */ + if (packet_compression) { + buffer_clear(&compression_buffer); + buffer_uncompress(&incoming_packet, &compression_buffer); + buffer_clear(&incoming_packet); + buffer_append(&incoming_packet, buffer_ptr(&compression_buffer), + buffer_len(&compression_buffer)); + } + /* Get packet type. */ + buffer_get(&incoming_packet, &buf[0], 1); + + /* Return length of payload (without type field). */ + *payload_len_ptr = buffer_len(&incoming_packet); + + /* Handle disconnect message. */ + if ((unsigned char) buf[0] == SSH_MSG_DISCONNECT) + fatal("Received disconnect: %.900s", packet_get_string(NULL)); + + /* Ignore ignore messages. */ + if ((unsigned char) buf[0] == SSH_MSG_IGNORE) + goto restart; + + /* Send debug messages as debugging output. */ + if ((unsigned char) buf[0] == SSH_MSG_DEBUG) { + debug("Remote: %.900s", packet_get_string(NULL)); + goto restart; + } + /* Return type. */ + return (unsigned char) buf[0]; +} + /* Buffers the given amount of input characters. This is intended to be used together with packet_read_poll. */ void packet_process_incoming(const char *buf, unsigned int len) { - buffer_append(&input, buf, len); + buffer_append(&input, buf, len); } /* Returns a character from the packet. */ @@ -544,9 +530,9 @@ packet_process_incoming(const char *buf, unsigned int len) unsigned int packet_get_char() { - char ch; - buffer_get(&incoming_packet, &ch, 1); - return (unsigned char)ch; + char ch; + buffer_get(&incoming_packet, &ch, 1); + return (unsigned char) ch; } /* Returns an integer from the packet data. */ @@ -554,16 +540,16 @@ packet_get_char() unsigned int packet_get_int() { - return buffer_get_int(&incoming_packet); + return buffer_get_int(&incoming_packet); } /* Returns an arbitrary precision integer from the packet data. The integer must have been initialized before this call. */ void -packet_get_bignum(BIGNUM *value, int *length_ptr) +packet_get_bignum(BIGNUM * value, int *length_ptr) { - *length_ptr = buffer_get_bignum(&incoming_packet, value); + *length_ptr = buffer_get_bignum(&incoming_packet, value); } /* Returns a string from the packet data. The string is allocated using @@ -572,9 +558,10 @@ packet_get_bignum(BIGNUM *value, int *length_ptr) integer into which the length of the string is stored. */ char -*packet_get_string(unsigned int *length_ptr) +* +packet_get_string(unsigned int *length_ptr) { - return buffer_get_string(&incoming_packet, length_ptr); + return buffer_get_string(&incoming_packet, length_ptr); } /* Sends a diagnostic message from the server to the client. This message @@ -586,19 +573,19 @@ char packet_write_wait. */ void -packet_send_debug(const char *fmt, ...) +packet_send_debug(const char *fmt,...) { - char buf[1024]; - va_list args; - - va_start(args, fmt); - vsnprintf(buf, sizeof(buf), fmt, args); - va_end(args); - - packet_start(SSH_MSG_DEBUG); - packet_put_string(buf, strlen(buf)); - packet_send(); - packet_write_wait(); + char buf[1024]; + va_list args; + + va_start(args, fmt); + vsnprintf(buf, sizeof(buf), fmt, args); + va_end(args); + + packet_start(SSH_MSG_DEBUG); + packet_put_string(buf, strlen(buf)); + packet_send(); + packet_write_wait(); } /* Logs the error plus constructs and sends a disconnect @@ -607,36 +594,35 @@ packet_send_debug(const char *fmt, ...) formatted message must not exceed 1024 bytes. */ void -packet_disconnect(const char *fmt, ...) -{ - char buf[1024]; - va_list args; - static int disconnecting = 0; - if (disconnecting) /* Guard against recursive invocations. */ - fatal("packet_disconnect called recursively."); - disconnecting = 1; - - /* Format the message. Note that the caller must make sure the message - is of limited size. */ - va_start(args, fmt); - vsnprintf(buf, sizeof(buf), fmt, args); - va_end(args); - - /* Send the disconnect message to the other side, and wait for it to get - sent. */ - packet_start(SSH_MSG_DISCONNECT); - packet_put_string(buf, strlen(buf)); - packet_send(); - packet_write_wait(); - - /* Stop listening for connections. */ - channel_stop_listening(); - - /* Close the connection. */ - packet_close(); - - /* Display the error locally and exit. */ - fatal("Local: %.100s", buf); +packet_disconnect(const char *fmt,...) +{ + char buf[1024]; + va_list args; + static int disconnecting = 0; + if (disconnecting) /* Guard against recursive invocations. */ + fatal("packet_disconnect called recursively."); + disconnecting = 1; + + /* Format the message. Note that the caller must make sure the + message is of limited size. */ + va_start(args, fmt); + vsnprintf(buf, sizeof(buf), fmt, args); + va_end(args); + + /* Send the disconnect message to the other side, and wait for it to get sent. */ + packet_start(SSH_MSG_DISCONNECT); + packet_put_string(buf, strlen(buf)); + packet_send(); + packet_write_wait(); + + /* Stop listening for connections. */ + channel_stop_listening(); + + /* Close the connection. */ + packet_close(); + + /* Display the error locally and exit. */ + fatal("Disconnecting: %.100s", buf); } /* Checks if there is any buffered output, and tries to write some of the @@ -645,18 +631,17 @@ packet_disconnect(const char *fmt, ...) void packet_write_poll() { - int len = buffer_len(&output); - if (len > 0) - { - len = write(connection_out, buffer_ptr(&output), len); - if (len <= 0) { - if (errno == EAGAIN) - return; - else - fatal("Write failed: %.100s", strerror(errno)); - } - buffer_consume(&output, len); - } + int len = buffer_len(&output); + if (len > 0) { + len = write(connection_out, buffer_ptr(&output), len); + if (len <= 0) { + if (errno == EAGAIN) + return; + else + fatal("Write failed: %.100s", strerror(errno)); + } + buffer_consume(&output, len); + } } /* Calls packet_write_poll repeatedly until all pending output data has @@ -665,15 +650,14 @@ packet_write_poll() void packet_write_wait() { - packet_write_poll(); - while (packet_have_data_to_write()) - { - fd_set set; - FD_ZERO(&set); - FD_SET(connection_out, &set); - select(connection_out + 1, NULL, &set, NULL, NULL); - packet_write_poll(); - } + packet_write_poll(); + while (packet_have_data_to_write()) { + fd_set set; + FD_ZERO(&set); + FD_SET(connection_out, &set); + select(connection_out + 1, NULL, &set, NULL, NULL); + packet_write_poll(); + } } /* Returns true if there is buffered data to write to the connection. */ @@ -681,7 +665,7 @@ packet_write_wait() int packet_have_data_to_write() { - return buffer_len(&output) != 0; + return buffer_len(&output) != 0; } /* Returns true if there is not too much data to write to the connection. */ @@ -689,10 +673,10 @@ packet_have_data_to_write() int packet_not_very_much_data_to_write() { - if (interactive_mode) - return buffer_len(&output) < 16384; - else - return buffer_len(&output) < 128*1024; + if (interactive_mode) + return buffer_len(&output) < 16384; + else + return buffer_len(&output) < 128 * 1024; } /* Informs that the current session is interactive. Sets IP flags for that. */ @@ -700,45 +684,40 @@ packet_not_very_much_data_to_write() void packet_set_interactive(int interactive, int keepalives) { - int on = 1; - - /* Record that we are in interactive mode. */ - interactive_mode = interactive; - - /* Only set socket options if using a socket (as indicated by the descriptors - being the same). */ - if (connection_in != connection_out) - return; - - if (keepalives) - { - /* Set keepalives if requested. */ - if (setsockopt(connection_in, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, - sizeof(on)) < 0) - error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); - } - - if (interactive) - { - /* Set IP options for an interactive connection. Use IPTOS_LOWDELAY - and TCP_NODELAY. */ - int lowdelay = IPTOS_LOWDELAY; - if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *)&lowdelay, - sizeof(lowdelay)) < 0) - error("setsockopt IPTOS_LOWDELAY: %.100s", strerror(errno)); - if (setsockopt(connection_in, IPPROTO_TCP, TCP_NODELAY, (void *)&on, - sizeof(on)) < 0) - error("setsockopt TCP_NODELAY: %.100s", strerror(errno)); - } - else - { - /* Set IP options for a non-interactive connection. Use - IPTOS_THROUGHPUT. */ - int throughput = IPTOS_THROUGHPUT; - if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *)&throughput, - sizeof(throughput)) < 0) - error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno)); - } + int on = 1; + + /* Record that we are in interactive mode. */ + interactive_mode = interactive; + + /* Only set socket options if using a socket (as indicated by the + descriptors being the same). */ + if (connection_in != connection_out) + return; + + if (keepalives) { + /* Set keepalives if requested. */ + if (setsockopt(connection_in, SOL_SOCKET, SO_KEEPALIVE, (void *) &on, + sizeof(on)) < 0) + error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); + } + if (interactive) { + /* Set IP options for an interactive connection. Use + IPTOS_LOWDELAY and TCP_NODELAY. */ + int lowdelay = IPTOS_LOWDELAY; + if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *) &lowdelay, + sizeof(lowdelay)) < 0) + error("setsockopt IPTOS_LOWDELAY: %.100s", strerror(errno)); + if (setsockopt(connection_in, IPPROTO_TCP, TCP_NODELAY, (void *) &on, + sizeof(on)) < 0) + error("setsockopt TCP_NODELAY: %.100s", strerror(errno)); + } else { + /* Set IP options for a non-interactive connection. Use + IPTOS_THROUGHPUT. */ + int throughput = IPTOS_THROUGHPUT; + if (setsockopt(connection_in, IPPROTO_IP, IP_TOS, (void *) &throughput, + sizeof(throughput)) < 0) + error("setsockopt IPTOS_THROUGHPUT: %.100s", strerror(errno)); + } } /* Returns true if the current connection is interactive. */ @@ -746,22 +725,22 @@ packet_set_interactive(int interactive, int keepalives) int packet_is_interactive() { - return interactive_mode; + return interactive_mode; } int packet_set_maxsize(int s) { - static int called = 0; - if (called) { - log("packet_set_maxsize: called twice: old %d new %d", max_packet_size, s); - return -1; - } - if (s < 4*1024 || s > 1024*1024) { - log("packet_set_maxsize: bad size %d", s); - return -1; - } - log("packet_set_maxsize: setting to %d", s); - max_packet_size = s; - return s; + static int called = 0; + if (called) { + log("packet_set_maxsize: called twice: old %d new %d", max_packet_size, s); + return -1; + } + if (s < 4 * 1024 || s > 1024 * 1024) { + log("packet_set_maxsize: bad size %d", s); + return -1; + } + log("packet_set_maxsize: setting to %d", s); + max_packet_size = s; + return s; } -- cgit v1.2.3