X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/8ce72d2c1c7651def2425be607ef623e6b0b9bd2..c9def1b8e8960113ab4fd91d0b69d5b422cf339f:/ssh.c diff --git a/ssh.c b/ssh.c index d3df6bcb..65f0075c 100644 --- a/ssh.c +++ b/ssh.c @@ -1,8 +1,12 @@ #include #include +#include +#include #include #include "putty.h" +#include "ssh.h" +#include "scp.h" #ifndef FALSE #define FALSE 0 @@ -11,29 +15,48 @@ #define TRUE 1 #endif -#include "ssh.h" - -#define SSH_MSG_DISCONNECT 1 -#define SSH_SMSG_PUBLIC_KEY 2 -#define SSH_CMSG_SESSION_KEY 3 -#define SSH_CMSG_USER 4 -#define SSH_CMSG_AUTH_PASSWORD 9 -#define SSH_CMSG_REQUEST_PTY 10 -#define SSH_CMSG_EXEC_SHELL 12 -#define SSH_CMSG_STDIN_DATA 16 -#define SSH_SMSG_STDOUT_DATA 17 -#define SSH_SMSG_STDERR_DATA 18 -#define SSH_SMSG_SUCCESS 14 -#define SSH_SMSG_FAILURE 15 -#define SSH_SMSG_EXITSTATUS 20 -#define SSH_MSG_IGNORE 32 -#define SSH_CMSG_EXIT_CONFIRMATION 33 -#define SSH_MSG_DEBUG 36 -#define SSH_CMSG_AUTH_TIS 39 -#define SSH_SMSG_AUTH_TIS_CHALLENGE 40 -#define SSH_CMSG_AUTH_TIS_RESPONSE 41 - -#define SSH_AUTH_TIS 5 +#define logevent(s) { logevent(s); \ + if (IS_SCP && (scp_flags & SCP_VERBOSE) != 0) \ + fprintf(stderr, "%s\n", s); } + +#define SSH_MSG_DISCONNECT 1 +#define SSH_SMSG_PUBLIC_KEY 2 +#define SSH_CMSG_SESSION_KEY 3 +#define SSH_CMSG_USER 4 +#define SSH_CMSG_AUTH_PASSWORD 9 +#define SSH_CMSG_REQUEST_PTY 10 +#define SSH_CMSG_WINDOW_SIZE 11 +#define SSH_CMSG_EXEC_SHELL 12 +#define SSH_CMSG_EXEC_CMD 13 +#define SSH_SMSG_SUCCESS 14 +#define SSH_SMSG_FAILURE 15 +#define SSH_CMSG_STDIN_DATA 16 +#define SSH_SMSG_STDOUT_DATA 17 +#define SSH_SMSG_STDERR_DATA 18 +#define SSH_CMSG_EOF 19 +#define SSH_SMSG_EXIT_STATUS 20 +#define SSH_CMSG_EXIT_CONFIRMATION 33 +#define SSH_MSG_IGNORE 32 +#define SSH_MSG_DEBUG 36 +#define SSH_CMSG_AUTH_TIS 39 +#define SSH_SMSG_AUTH_TIS_CHALLENGE 40 +#define SSH_CMSG_AUTH_TIS_RESPONSE 41 + +#define SSH_AUTH_TIS 5 + +#define GET_32BIT(cp) \ + (((unsigned long)(unsigned char)(cp)[0] << 24) | \ + ((unsigned long)(unsigned char)(cp)[1] << 16) | \ + ((unsigned long)(unsigned char)(cp)[2] << 8) | \ + ((unsigned long)(unsigned char)(cp)[3])) + +#define PUT_32BIT(cp, value) { \ + (cp)[0] = (unsigned char)((value) >> 24); \ + (cp)[1] = (unsigned char)((value) >> 16); \ + (cp)[2] = (unsigned char)((value) >> 8); \ + (cp)[3] = (unsigned char)(value); } + +enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR }; /* Coroutine mechanics for the sillier bits of the code */ #define crBegin1 static int crLine = 0; @@ -51,18 +74,14 @@ } while (0) #define crStop(z) do{ crLine = 0; return (z); }while(0) #define crStopV do{ crLine = 0; return; }while(0) - -#ifndef FALSE -#define FALSE 0 -#endif -#ifndef TRUE -#define TRUE 1 -#endif +#define crWaitUntil(c) do { crReturn(0); } while (!(c)) static SOCKET s = INVALID_SOCKET; static unsigned char session_key[32]; static struct ssh_cipher *cipher = NULL; +int scp_flags = 0; +int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL; static char *savedhost; @@ -78,6 +97,11 @@ static int size_needed = FALSE; static void s_write (char *buf, int len) { while (len > 0) { int i = send (s, buf, len, 0); + if (IS_SCP) { + noise_ultralight(i); + if (i <= 0) + fatalbox("Lost connection while sending"); + } if (i > 0) len -= i, buf += i; } @@ -87,6 +111,8 @@ static int s_read (char *buf, int len) { int ret = 0; while (len > 0) { int i = recv (s, buf, len, 0); + if (IS_SCP) + noise_ultralight(i); if (i > 0) len -= i, buf += i, ret += i; else @@ -96,96 +122,153 @@ static int s_read (char *buf, int len) { } static void c_write (char *buf, int len) { - while (len--) { - int new_head = (inbuf_head + 1) & INBUF_MASK; - if (new_head != inbuf_reap) { - inbuf[inbuf_head] = *buf++; - inbuf_head = new_head; - } + if (IS_SCP) { + if (len > 0 && buf[len-1] == '\n') len--; + if (len > 0 && buf[len-1] == '\r') len--; + if (len > 0) { fwrite(buf, len, 1, stderr); fputc('\n', stderr); } + return; } + while (len--) + c_write1(*buf++); } struct Packet { long length; int type; - unsigned long crc; unsigned char *data; unsigned char *body; long maxlen; }; -static struct Packet pktin = { 0, 0, 0, NULL, 0 }; -static struct Packet pktout = { 0, 0, 0, NULL, 0 }; +static struct Packet pktin = { 0, 0, NULL, NULL, 0 }; +static struct Packet pktout = { 0, 0, NULL, NULL, 0 }; static void ssh_protocol(unsigned char *in, int inlen, int ispkt); static void ssh_size(void); -static void ssh_gotdata(unsigned char *data, int datalen) { - static long len, biglen, to_read; + +/* + * Collect incoming data in the incoming packet buffer. + * Decihper and verify the packet when it is completely read. + * Drop SSH_MSG_DEBUG and SSH_MSG_IGNORE packets. + * Update the *data and *datalen variables. + * Return the additional nr of bytes needed, or 0 when + * a complete packet is available. + */ +static int s_rdpkt(unsigned char **data, int *datalen) +{ + static long len, pad, biglen, to_read; + static unsigned long realcrc, gotcrc; static unsigned char *p; - static int i, pad; + static int i; crBegin; - while (1) { - for (i = len = 0; i < 4; i++) { - while (datalen == 0) - crReturnV; - len = (len << 8) + *data; - data++, datalen--; - } + +next_packet: + + pktin.type = 0; + pktin.length = 0; + + for (i = len = 0; i < 4; i++) { + while ((*datalen) == 0) + crReturn(4-i); + len = (len << 8) + **data; + (*data)++, (*datalen)--; + } #ifdef FWHACK - if (len == 0x52656d6f) { /* "Remo"te server has closed ... */ - len = 0x300; /* big enough to carry to end */ - } + if (len == 0x52656d6f) { /* "Remo"te server has closed ... */ + len = 0x300; /* big enough to carry to end */ + } #endif - pad = 8 - (len%8); + pad = 8 - (len % 8); + biglen = len + pad; + pktin.length = len - 5; + + if (pktin.maxlen < biglen) { + pktin.maxlen = biglen; +#ifdef MSCRYPTOAPI + /* Allocate enough buffer space for extra block + * for MS CryptEncrypt() */ + pktin.data = (pktin.data == NULL ? malloc(biglen+8) : + realloc(pktin.data, biglen+8)); +#else + pktin.data = (pktin.data == NULL ? malloc(biglen) : + realloc(pktin.data, biglen)); +#endif + if (!pktin.data) + fatalbox("Out of memory"); + } - biglen = len + pad; + to_read = biglen; + p = pktin.data; + while (to_read > 0) { + static int chunk; + chunk = to_read; + while ((*datalen) == 0) + crReturn(to_read); + if (chunk > (*datalen)) + chunk = (*datalen); + memcpy(p, *data, chunk); + *data += chunk; + *datalen -= chunk; + p += chunk; + to_read -= chunk; + } - len -= 5; /* type and CRC */ + if (cipher) + cipher->decrypt(pktin.data, biglen); - pktin.length = len; - if (pktin.maxlen < biglen) { - pktin.maxlen = biglen; - pktin.data = (pktin.data == NULL ? malloc(biglen) : - realloc(pktin.data, biglen)); - if (!pktin.data) - fatalbox("Out of memory"); - } + pktin.type = pktin.data[pad]; + pktin.body = pktin.data + pad + 1; - p = pktin.data, to_read = biglen; - while (to_read > 0) { - static int chunk; - chunk = to_read; - while (datalen == 0) - crReturnV; - if (chunk > datalen) - chunk = datalen; - memcpy(p, data, chunk); - data += chunk; - datalen -= chunk; - p += chunk; - to_read -= chunk; - } + realcrc = crc32(pktin.data, biglen-4); + gotcrc = GET_32BIT(pktin.data+biglen-4); + if (gotcrc != realcrc) { + fatalbox("Incorrect CRC received on packet"); + } + + if (pktin.type == SSH_SMSG_STDOUT_DATA || + pktin.type == SSH_SMSG_STDERR_DATA || + pktin.type == SSH_MSG_DEBUG || + pktin.type == SSH_SMSG_AUTH_TIS_CHALLENGE) { + long strlen = GET_32BIT(pktin.body); + if (strlen + 4 != pktin.length) + fatalbox("Received data packet with bogus string length"); + } - if (cipher) - cipher->decrypt(pktin.data, biglen); + if (pktin.type == SSH_MSG_DEBUG) { + /* log debug message */ + char buf[80]; + int strlen = GET_32BIT(pktin.body); + strcpy(buf, "Remote: "); + if (strlen > 70) strlen = 70; + memcpy(buf+8, pktin.body+4, strlen); + buf[8+strlen] = '\0'; + logevent(buf); + goto next_packet; + } else if (pktin.type == SSH_MSG_IGNORE) { + /* do nothing */ + goto next_packet; + } - pktin.type = pktin.data[pad]; - pktin.body = pktin.data+pad+1; + crFinish(0); +} - if (pktin.type == SSH_MSG_DEBUG) { - /* FIXME: log it */ - } else if (pktin.type == SSH_MSG_IGNORE) { - /* do nothing */; - } else +static void ssh_gotdata(unsigned char *data, int datalen) +{ + while (datalen > 0) { + if ( s_rdpkt(&data, &datalen) == 0 ) { ssh_protocol(NULL, 0, 1); + if (ssh_state == SSH_STATE_CLOSED) { + return; + } + } } - crFinishV; } + static void s_wrpkt_start(int type, int len) { int pad, biglen; @@ -196,8 +279,15 @@ static void s_wrpkt_start(int type, int len) { pktout.length = len-5; if (pktout.maxlen < biglen) { pktout.maxlen = biglen; +#ifdef MSCRYPTOAPI + /* Allocate enough buffer space for extra block + * for MS CryptEncrypt() */ + pktout.data = (pktout.data == NULL ? malloc(biglen+12) : + realloc(pktout.data, biglen+12)); +#else pktout.data = (pktout.data == NULL ? malloc(biglen+4) : realloc(pktout.data, biglen+4)); +#endif if (!pktout.data) fatalbox("Out of memory"); } @@ -218,16 +308,8 @@ static void s_wrpkt(void) { for (i=0; i> 24) & 0xFF); - pktout.data[biglen+1] = (unsigned char) ((crc >> 16) & 0xFF); - pktout.data[biglen+2] = (unsigned char) ((crc >> 8) & 0xFF); - pktout.data[biglen+3] = (unsigned char) (crc & 0xFF); - - pktout.data[0] = (len >> 24) & 0xFF; - pktout.data[1] = (len >> 16) & 0xFF; - pktout.data[2] = (len >> 8) & 0xFF; - pktout.data[3] = len & 0xFF; + PUT_32BIT(pktout.data+biglen, crc); + PUT_32BIT(pktout.data, len); if (cipher) cipher->encrypt(pktout.data+4, biglen); @@ -235,6 +317,183 @@ static void s_wrpkt(void) { s_write(pktout.data, biglen+4); } +/* + * Construct a packet with the specified contents and + * send it to the server. + */ +static void send_packet(int pkttype, ...) +{ + va_list args; + unsigned char *p, *argp, argchar; + unsigned long argint; + int pktlen, argtype, arglen; + + pktlen = 0; + va_start(args, pkttype); + while ((argtype = va_arg(args, int)) != PKT_END) { + switch (argtype) { + case PKT_INT: + (void) va_arg(args, int); + pktlen += 4; + break; + case PKT_CHAR: + (void) va_arg(args, char); + pktlen++; + break; + case PKT_DATA: + (void) va_arg(args, unsigned char *); + arglen = va_arg(args, int); + pktlen += arglen; + break; + case PKT_STR: + argp = va_arg(args, unsigned char *); + arglen = strlen(argp); + pktlen += 4 + arglen; + break; + default: + assert(0); + } + } + va_end(args); + + s_wrpkt_start(pkttype, pktlen); + p = pktout.body; + + va_start(args, pkttype); + while ((argtype = va_arg(args, int)) != PKT_END) { + switch (argtype) { + case PKT_INT: + argint = va_arg(args, int); + PUT_32BIT(p, argint); + p += 4; + break; + case PKT_CHAR: + argchar = va_arg(args, unsigned char); + *p = argchar; + p++; + break; + case PKT_DATA: + argp = va_arg(args, unsigned char *); + arglen = va_arg(args, int); + memcpy(p, argp, arglen); + p += arglen; + break; + case PKT_STR: + argp = va_arg(args, unsigned char *); + arglen = strlen(argp); + PUT_32BIT(p, arglen); + memcpy(p + 4, argp, arglen); + p += 4 + arglen; + break; + } + } + va_end(args); + + s_wrpkt(); +} + + +/* + * Connect to specified host and port. + * Returns an error message, or NULL on success. + * Also places the canonical host name into `realhost'. + */ +static char *connect_to_host(char *host, int port, char **realhost) +{ + SOCKADDR_IN addr; + struct hostent *h; + unsigned long a; +#ifdef FWHACK + char *FWhost; + int FWport; +#endif + + savedhost = malloc(1+strlen(host)); + if (!savedhost) + fatalbox("Out of memory"); + strcpy(savedhost, host); + + if (port < 0) + port = 22; /* default ssh port */ + +#ifdef FWHACK + FWhost = host; + FWport = port; + host = FWSTR; + port = 23; +#endif + + /* + * Try to find host. + */ + if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) { + if ( (h = gethostbyname(host)) == NULL) + switch (WSAGetLastError()) { + case WSAENETDOWN: return "Network is down"; + case WSAHOST_NOT_FOUND: case WSANO_DATA: + return "Host does not exist"; + case WSATRY_AGAIN: return "Host not found"; + default: return "gethostbyname: unknown error"; + } + memcpy (&a, h->h_addr, sizeof(a)); + *realhost = h->h_name; + } else + *realhost = host; +#ifdef FWHACK + *realhost = FWhost; +#endif + a = ntohl(a); + + /* + * Open socket. + */ + s = socket(AF_INET, SOCK_STREAM, 0); + if (s == INVALID_SOCKET) + switch (WSAGetLastError()) { + case WSAENETDOWN: return "Network is down"; + case WSAEAFNOSUPPORT: return "TCP/IP support not present"; + default: return "socket(): unknown error"; + } + + /* + * Bind to local address. + */ + addr.sin_family = AF_INET; + addr.sin_addr.s_addr = htonl(INADDR_ANY); + addr.sin_port = htons(0); + if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) + switch (WSAGetLastError()) { + case WSAENETDOWN: return "Network is down"; + default: return "bind(): unknown error"; + } + + /* + * Connect to remote address. + */ + addr.sin_addr.s_addr = htonl(a); + addr.sin_port = htons((short)port); + if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) + switch (WSAGetLastError()) { + case WSAENETDOWN: return "Network is down"; + case WSAECONNREFUSED: return "Connection refused"; + case WSAENETUNREACH: return "Network is unreachable"; + case WSAEHOSTUNREACH: return "No route to host"; + default: return "connect(): unknown error"; + } + +#ifdef FWHACK + send(s, "connect ", 8, 0); + send(s, FWhost, strlen(FWhost), 0); + { + char buf[20]; + sprintf(buf, " %d\n", FWport); + send (s, buf, strlen(buf), 0); + } +#endif + + return NULL; +} + static int ssh_versioncmp(char *a, char *b) { char *ae, *be; unsigned long av, bv; @@ -304,7 +563,11 @@ static int do_ssh_init(void) { return 1; } -static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { +/* + * Handle the key exchange and user authentication phases. + */ +static int do_ssh_login(unsigned char *in, int inlen, int ispkt) +{ int i, j, len; unsigned char session_id[16]; unsigned char *rsabuf, *keystr1, *keystr2; @@ -320,10 +583,7 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { crBegin; - random_init(); - - while (!ispkt) - crReturnV; + if (!ispkt) crWaitUntil(ispkt); if (pktin.type != SSH_SMSG_PUBLIC_KEY) fatalbox("Public key packet not received"); @@ -333,7 +593,6 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { memcpy(cookie, pktin.body, 8); i = makekey(pktin.body+8, &servkey, &keystr1); - j = makekey(pktin.body+8+i, &hostkey, &keystr2); /* @@ -355,22 +614,13 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { logevent(logmsg); } - supported_ciphers_mask = ((pktin.body[12+i+j] << 24) | - (pktin.body[13+i+j] << 16) | - (pktin.body[14+i+j] << 8) | - (pktin.body[15+i+j])); - - supported_auths_mask = ((pktin.body[16+i+j] << 24) | - (pktin.body[17+i+j] << 16) | - (pktin.body[18+i+j] << 8) | - (pktin.body[19+i+j])); + supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j); + supported_auths_mask = GET_32BIT(pktin.body+16+i+j); MD5Init(&md5c); - MD5Update(&md5c, keystr2, hostkey.bytes); MD5Update(&md5c, keystr1, servkey.bytes); MD5Update(&md5c, pktin.body, 8); - MD5Final(session_id, &md5c); for (i=0; i<32; i++) @@ -382,7 +632,21 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { if (!rsabuf) fatalbox("Out of memory"); - verify_ssh_host_key(savedhost, &hostkey); + /* + * Verify the host key. + */ + { + /* + * First format the key into a string. + */ + int len = rsastr_len(&hostkey); + char *keystr = malloc(len); + if (!keystr) + fatalbox("Out of memory"); + rsastr_fmt(keystr, &hostkey); + verify_ssh_host_key(savedhost, keystr); + free(keystr); + } for (i=0; i<32; i++) { rsabuf[i] = session_key[i]; @@ -413,15 +677,14 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break; } - s_wrpkt_start(SSH_CMSG_SESSION_KEY, len+15); - pktout.body[0] = cipher_type; - memcpy(pktout.body+1, cookie, 8); - pktout.body[9] = (len*8) >> 8; - pktout.body[10] = (len*8) & 0xFF; - memcpy(pktout.body+11, rsabuf, len); - pktout.body[len+11] = pktout.body[len+12] = 0; /* protocol flags */ - pktout.body[len+13] = pktout.body[len+14] = 0; - s_wrpkt(); + send_packet(SSH_CMSG_SESSION_KEY, + PKT_CHAR, cipher_type, + PKT_DATA, cookie, 8, + PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF, + PKT_DATA, rsabuf, len, + PKT_INT, 0, + PKT_END); + logevent("Trying to enable encryption..."); free(rsabuf); @@ -431,7 +694,7 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { &ssh_3des; cipher->sesskey(session_key); - do { crReturnV; } while (!ispkt); + crWaitUntil(ispkt); if (pktin.type != SSH_SMSG_SUCCESS) fatalbox("Encryption not successfully enabled"); @@ -443,10 +706,10 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { static char username[100]; static int pos = 0; static char c; - if (!*cfg.username) { + if (!IS_SCP && !*cfg.username) { c_write("login as: ", 10); while (pos >= 0) { - do { crReturnV; } while (ispkt); + crWaitUntil(!ispkt); while (inlen--) switch (c = *in++) { case 10: case 13: username[pos] = 0; @@ -469,7 +732,8 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { exit(0); break; default: - if (c >= ' ' && c <= '~' && pos < 40) { + if (((c >= ' ' && c <= '~') || + ((unsigned char)c >= 160)) && pos < 40) { username[pos++] = c; c_write(&c, 1); } @@ -482,22 +746,21 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { char stuff[200]; strncpy(username, cfg.username, 99); username[99] = '\0'; - sprintf(stuff, "Sent username \"%s\".\r\n", username); - c_write(stuff, strlen(stuff)); + if (!IS_SCP) { + sprintf(stuff, "Sent username \"%s\".\r\n", username); + c_write(stuff, strlen(stuff)); + } } - s_wrpkt_start(SSH_CMSG_USER, 4+strlen(username)); + + send_packet(SSH_CMSG_USER, PKT_STR, username, PKT_END); { char userlog[20+sizeof(username)]; sprintf(userlog, "Sent username \"%s\"", username); logevent(userlog); } - pktout.body[0] = pktout.body[1] = pktout.body[2] = 0; - pktout.body[3] = strlen(username); - memcpy(pktout.body+4, username, strlen(username)); - s_wrpkt(); } - do { crReturnV; } while (!ispkt); + crWaitUntil(ispkt); while (pktin.type == SSH_SMSG_FAILURE) { static char password[100]; @@ -510,14 +773,30 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { * exchange if we're doing TIS authentication. */ pwpkt_type = SSH_CMSG_AUTH_PASSWORD; + + if (IS_SCP) { + char prompt[200]; + sprintf(prompt, "%s@%s's password: ", cfg.username, savedhost); + if (!ssh_get_password(prompt, password, sizeof(password))) { + /* + * get_password failed to get a password (for + * example because one was supplied on the command + * line which has already failed to work). + * Terminate. + */ + logevent("No more passwords to try"); + ssh_state = SSH_STATE_CLOSED; + crReturn(1); + } + } else { + if (pktin.type == SSH_SMSG_FAILURE && cfg.try_tis_auth && (supported_auths_mask & (1<= 0) { - do { crReturnV; } while (ispkt); + crWaitUntil(!ispkt); while (inlen--) switch (c = *in++) { case 10: case 13: password[pos] = 0; @@ -553,49 +832,55 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { exit(0); break; default: - if (c >= ' ' && c <= '~' && pos < 40) + if (((c >= ' ' && c <= '~') || + ((unsigned char)c >= 160)) && pos < 40) password[pos++] = c; break; } } c_write("\r\n", 2); - s_wrpkt_start(pwpkt_type, 4+strlen(password)); - pktout.body[0] = pktout.body[1] = pktout.body[2] = 0; - pktout.body[3] = strlen(password); - memcpy(pktout.body+4, password, strlen(password)); - s_wrpkt(); + + } + + send_packet(pwpkt_type, PKT_STR, password, PKT_END); logevent("Sent password"); memset(password, 0, strlen(password)); - do { crReturnV; } while (!ispkt); - if (pktin.type == 15) { + crWaitUntil(ispkt); + if (pktin.type == SSH_SMSG_FAILURE) { c_write("Access denied\r\n", 15); logevent("Authentication refused"); - } else if (pktin.type != 14) { + } else if (pktin.type == SSH_MSG_DISCONNECT) { + logevent("Received disconnect request"); + ssh_state = SSH_STATE_CLOSED; + crReturn(1); + } else if (pktin.type != SSH_SMSG_SUCCESS) { fatalbox("Strange packet received, type %d", pktin.type); } } logevent("Authentication successful"); + crFinish(1); +} + +static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { + crBegin; + + random_init(); + + while (!do_ssh_login(in, inlen, ispkt)) { + crReturnV; + } + if (ssh_state == SSH_STATE_CLOSED) + crReturnV; + if (!cfg.nopty) { - i = strlen(cfg.termtype); - s_wrpkt_start(SSH_CMSG_REQUEST_PTY, i+5*4+1); - pktout.body[0] = (i >> 24) & 0xFF; - pktout.body[1] = (i >> 16) & 0xFF; - pktout.body[2] = (i >> 8) & 0xFF; - pktout.body[3] = i & 0xFF; - memcpy(pktout.body+4, cfg.termtype, i); - i += 4; - pktout.body[i++] = (rows >> 24) & 0xFF; - pktout.body[i++] = (rows >> 16) & 0xFF; - pktout.body[i++] = (rows >> 8) & 0xFF; - pktout.body[i++] = rows & 0xFF; - pktout.body[i++] = (cols >> 24) & 0xFF; - pktout.body[i++] = (cols >> 16) & 0xFF; - pktout.body[i++] = (cols >> 8) & 0xFF; - pktout.body[i++] = cols & 0xFF; - memset(pktout.body+i, 0, 9); /* 0 pixwidth, 0 pixheight, 0.b endofopt */ - s_wrpkt(); + send_packet(SSH_CMSG_REQUEST_PTY, + PKT_STR, cfg.termtype, + PKT_INT, rows, PKT_INT, cols, + PKT_INT, 0, PKT_INT, 0, + PKT_CHAR, 0, + PKT_END); ssh_state = SSH_STATE_INTERMED; do { crReturnV; } while (!ispkt); if (pktin.type != SSH_SMSG_SUCCESS && pktin.type != SSH_SMSG_FAILURE) { @@ -606,8 +891,7 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { logevent("Allocated pty"); } - s_wrpkt_start(SSH_CMSG_EXEC_SHELL, 0); - s_wrpkt(); + send_packet(SSH_CMSG_EXEC_SHELL, PKT_END); logevent("Started session"); ssh_state = SSH_STATE_SESSION; @@ -619,9 +903,7 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { if (ispkt) { if (pktin.type == SSH_SMSG_STDOUT_DATA || pktin.type == SSH_SMSG_STDERR_DATA) { - long len = 0; - for (i = 0; i < 4; i++) - len = (len << 8) + pktin.body[i]; + long len = GET_32BIT(pktin.body); c_write(pktin.body+4, len); } else if (pktin.type == SSH_MSG_DISCONNECT) { ssh_state = SSH_STATE_CLOSED; @@ -631,20 +913,14 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { } else if (pktin.type == SSH_SMSG_FAILURE) { /* may be from EXEC_SHELL on some servers * if no pty is available or in other odd cases. Ignore */ - } else if (pktin.type == SSH_SMSG_EXITSTATUS) { - s_wrpkt_start(SSH_CMSG_EXIT_CONFIRMATION, 0); - s_wrpkt(); + } else if (pktin.type == SSH_SMSG_EXIT_STATUS) { + send_packet(SSH_CMSG_EXIT_CONFIRMATION, PKT_END); } else { fatalbox("Strange packet received: type %d", pktin.type); } } else { - s_wrpkt_start(SSH_CMSG_STDIN_DATA, 4+inlen); - pktout.body[0] = (inlen >> 24) & 0xFF; - pktout.body[1] = (inlen >> 16) & 0xFF; - pktout.body[2] = (inlen >> 8) & 0xFF; - pktout.body[3] = inlen & 0xFF; - memcpy(pktout.body+4, in, inlen); - s_wrpkt(); + send_packet(SSH_CMSG_STDIN_DATA, + PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END); } } @@ -657,100 +933,18 @@ static void ssh_protocol(unsigned char *in, int inlen, int ispkt) { * procedure should then call telnet_msg(). * * Returns an error message, or NULL on success. - * - * Also places the canonical host name into `realhost'. */ static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) { - SOCKADDR_IN addr; - struct hostent *h; - unsigned long a; -#ifdef FWHACK - char *FWhost; - int FWport; -#endif - - savedhost = malloc(1+strlen(host)); - if (!savedhost) - fatalbox("Out of memory"); - strcpy(savedhost, host); - -#ifdef FWHACK - FWhost = host; - FWport = port; - host = FWSTR; - port = 23; -#endif - - /* - * Try to find host. - */ - if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) { - if ( (h = gethostbyname(host)) == NULL) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - case WSAHOST_NOT_FOUND: case WSANO_DATA: - return "Host does not exist"; - case WSATRY_AGAIN: return "Host not found"; - default: return "gethostbyname: unknown error"; - } - memcpy (&a, h->h_addr, sizeof(a)); - *realhost = h->h_name; - } else - *realhost = host; -#ifdef FWHACK - *realhost = FWhost; + char *p; + +#ifdef MSCRYPTOAPI + if(crypto_startup() == 0) + return "Microsoft high encryption pack not installed!"; #endif - a = ntohl(a); - - if (port < 0) - port = 22; /* default ssh port */ - - /* - * Open socket. - */ - s = socket(AF_INET, SOCK_STREAM, 0); - if (s == INVALID_SOCKET) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - case WSAEAFNOSUPPORT: return "TCP/IP support not present"; - default: return "socket(): unknown error"; - } - - /* - * Bind to local address. - */ - addr.sin_family = AF_INET; - addr.sin_addr.s_addr = htonl(INADDR_ANY); - addr.sin_port = htons(0); - if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - default: return "bind(): unknown error"; - } - - /* - * Connect to remote address. - */ - addr.sin_addr.s_addr = htonl(a); - addr.sin_port = htons((short)port); - if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR) - switch (WSAGetLastError()) { - case WSAENETDOWN: return "Network is down"; - case WSAECONNREFUSED: return "Connection refused"; - case WSAENETUNREACH: return "Network is unreachable"; - case WSAEHOSTUNREACH: return "No route to host"; - default: return "connect(): unknown error"; - } -#ifdef FWHACK - send(s, "connect ", 8, 0); - send(s, FWhost, strlen(FWhost), 0); - { - char buf[20]; - sprintf(buf, " %d\n", FWport); - send (s, buf, strlen(buf), 0); - } -#endif + p = connect_to_host(host, port, realhost); + if (p != NULL) + return p; if (!do_ssh_init()) return "Protocol initialisation error"; @@ -798,6 +992,11 @@ static int ssh_msg (WPARAM wParam, LPARAM lParam) { return 0; } ssh_gotdata (buf, ret); + if (ssh_state == SSH_STATE_CLOSED) { + closesocket(s); + s = INVALID_SOCKET; + return 0; + } return 1; } return 1; /* shouldn't happen, but WTF */ @@ -826,17 +1025,9 @@ static void ssh_size(void) { break; case SSH_STATE_SESSION: if (!cfg.nopty) { - s_wrpkt_start(11, 16); - pktout.body[0] = (rows >> 24) & 0xFF; - pktout.body[1] = (rows >> 16) & 0xFF; - pktout.body[2] = (rows >> 8) & 0xFF; - pktout.body[3] = rows & 0xFF; - pktout.body[4] = (cols >> 24) & 0xFF; - pktout.body[5] = (cols >> 16) & 0xFF; - pktout.body[6] = (cols >> 8) & 0xFF; - pktout.body[7] = cols & 0xFF; - memset(pktout.body+8, 0, 8); - s_wrpkt(); + send_packet(SSH_CMSG_WINDOW_SIZE, + PKT_INT, rows, PKT_INT, cols, + PKT_INT, 0, PKT_INT, 0, PKT_END); } } } @@ -848,6 +1039,179 @@ static void ssh_special (Telnet_Special code) { /* do nothing */ } + +/* + * Read and decrypt one incoming SSH packet. + * (only used by pSCP) + */ +static void get_packet(void) +{ + unsigned char buf[4096], *p; + long to_read; + int len; + + assert(IS_SCP); + + p = NULL; + len = 0; + + while ((to_read = s_rdpkt(&p, &len)) > 0) { + if (to_read > sizeof(buf)) to_read = sizeof(buf); + len = s_read(buf, to_read); + if (len != to_read) { + closesocket(s); + s = INVALID_SOCKET; + return; + } + p = buf; + } + + assert(len == 0); +} + +/* + * Receive a block of data over the SSH link. Block until + * all data is available. Return nr of bytes read (0 if lost connection). + * (only used by pSCP) + */ +int ssh_scp_recv(unsigned char *buf, int len) +{ + static int pending_input_len = 0; + static unsigned char *pending_input_ptr; + int to_read = len; + + assert(IS_SCP); + + if (pending_input_len >= to_read) { + memcpy(buf, pending_input_ptr, to_read); + pending_input_ptr += to_read; + pending_input_len -= to_read; + return len; + } + + if (pending_input_len > 0) { + memcpy(buf, pending_input_ptr, pending_input_len); + buf += pending_input_len; + to_read -= pending_input_len; + pending_input_len = 0; + } + + if (s == INVALID_SOCKET) + return 0; + while (to_read > 0) { + get_packet(); + if (s == INVALID_SOCKET) + return 0; + if (pktin.type == SSH_SMSG_STDOUT_DATA) { + int plen = GET_32BIT(pktin.body); + if (plen <= to_read) { + memcpy(buf, pktin.body + 4, plen); + buf += plen; + to_read -= plen; + } else { + memcpy(buf, pktin.body + 4, to_read); + pending_input_len = plen - to_read; + pending_input_ptr = pktin.body + 4 + to_read; + to_read = 0; + } + } else if (pktin.type == SSH_SMSG_STDERR_DATA) { + int plen = GET_32BIT(pktin.body); + fwrite(pktin.body + 4, plen, 1, stderr); + } else if (pktin.type == SSH_MSG_DISCONNECT) { + logevent("Received disconnect request"); + } else if (pktin.type == SSH_SMSG_SUCCESS || + pktin.type == SSH_SMSG_FAILURE) { + /* ignore */ + } else if (pktin.type == SSH_SMSG_EXIT_STATUS) { + char logbuf[100]; + sprintf(logbuf, "Remote exit status: %d", GET_32BIT(pktin.body)); + logevent(logbuf); + send_packet(SSH_CMSG_EXIT_CONFIRMATION, PKT_END); + logevent("Closing connection"); + closesocket(s); + s = INVALID_SOCKET; + } else { + fatalbox("Strange packet received: type %d", pktin.type); + } + } + + return len; +} + +/* + * Send a block of data over the SSH link. + * Block until all data is sent. + * (only used by pSCP) + */ +void ssh_scp_send(unsigned char *buf, int len) +{ + assert(IS_SCP); + if (s == INVALID_SOCKET) + return; + send_packet(SSH_CMSG_STDIN_DATA, + PKT_INT, len, PKT_DATA, buf, len, PKT_END); +} + +/* + * Send an EOF notification to the server. + * (only used by pSCP) + */ +void ssh_scp_send_eof(void) +{ + assert(IS_SCP); + if (s == INVALID_SOCKET) + return; + send_packet(SSH_CMSG_EOF, PKT_END); +} + +/* + * Set up the connection, login on the remote host and + * start execution of a command. + * Returns an error message, or NULL on success. + * (only used by pSCP) + */ +char *ssh_scp_init(char *host, int port, char *cmd, char **realhost) +{ + char buf[160], *p; + + assert(IS_SCP); + +#ifdef MSCRYPTOAPI + if (crypto_startup() == 0) + return "Microsoft high encryption pack not installed!"; +#endif + + p = connect_to_host(host, port, realhost); + if (p != NULL) + return p; + + random_init(); + + if (!do_ssh_init()) + return "Protocol initialisation error"; + + /* Exchange keys and login */ + do { + get_packet(); + if (s == INVALID_SOCKET) + return "Connection closed by remote host"; + } while (!do_ssh_login(NULL, 0, 1)); + + if (ssh_state == SSH_STATE_CLOSED) { + closesocket(s); + s = INVALID_SOCKET; + return "Session initialisation error"; + } + + /* Execute command */ + sprintf(buf, "Sending command: %.100s", cmd); + logevent(buf); + send_packet(SSH_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END); + + return NULL; +} + + Backend ssh_backend = { ssh_init, ssh_msg, @@ -855,3 +1219,4 @@ Backend ssh_backend = { ssh_size, ssh_special }; +