X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/1dd353b59d3feeaef262801cde4a023eed3c983e..38d228a25df956ea1c28bd5d5b234bd07b0140a7:/ssh.c?ds=sidebyside diff --git a/ssh.c b/ssh.c index 339b98ea..a3ac60b4 100644 --- a/ssh.c +++ b/ssh.c @@ -515,8 +515,6 @@ static const struct ssh_compress *sccomp = NULL; static const struct ssh_kex *kex = NULL; static const struct ssh_signkey *hostkey = NULL; static unsigned char ssh2_session_id[20]; -int (*ssh_get_line) (const char *prompt, char *str, int maxlen, - int is_pw) = NULL; static char *savedhost; static int savedport; @@ -1541,6 +1539,7 @@ static int ssh2_pkt_getbool(void) static void ssh2_pkt_getstring(char **p, int *length) { *p = NULL; + *length = 0; if (pktin.length - pktin.savedpos < 4) return; *length = GET_32BIT(pktin.data + pktin.savedpos); @@ -1711,6 +1710,7 @@ static int do_ssh_init(unsigned char c) static int vstrsize; static char *vlog; static int i; + static int proto1, proto2; crBegin; @@ -1767,12 +1767,26 @@ static int do_ssh_init(unsigned char c) sfree(vlog); /* - * Server version "1.99" means we can choose whether we use v1 - * or v2 protocol. Choice is based on cfg.sshprot. + * Decide which SSH protocol version to support. */ - if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) { + + /* Anything strictly below "2.0" means protocol 1 is supported. */ + proto1 = ssh_versioncmp(version, "2.0") < 0; + /* Anything greater or equal to "1.99" means protocol 2 is supported. */ + proto2 = ssh_versioncmp(version, "1.99") > 0; + + if (cfg.sshprot == 0 && !proto1) { + bombout(("SSH protocol version 1 required by user but not provided by server")); + crReturn(0); + } + if (cfg.sshprot == 3 && !proto2) { + bombout(("SSH protocol version 2 required by user but not provided by server")); + crReturn(0); + } + + if (proto2 && (cfg.sshprot == 2 || !proto1)) { /* - * This is a v2 server. Begin v2 protocol. + * Use v2 protocol. */ char verstring[80], vlog[100]; sprintf(verstring, "SSH-2.0-%s", sshver); @@ -1792,7 +1806,7 @@ static int do_ssh_init(unsigned char c) s_rdpkt = ssh2_rdpkt; } else { /* - * This is a v1 server. Begin v1 protocol. + * Use v1 protocol. */ char verstring[80], vlog[100]; sprintf(verstring, "SSH-%s-%s", @@ -1801,11 +1815,6 @@ static int do_ssh_init(unsigned char c) sprintf(vlog, "We claim version: %s", verstring); logevent(vlog); strcat(verstring, "\n"); - - if (cfg.sshprot == 3) { - bombout(("SSH protocol version 2 required by user but not provided by server")); - crReturn(0); - } logevent("Using SSH protocol version 1"); sk_write(s, verstring, strlen(verstring)); @@ -2227,7 +2236,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt) static int pos = 0; static char c; if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { - if (ssh_get_line) { + if (ssh_get_line && !ssh_getline_pw_only) { if (!ssh_get_line("login as: ", username, sizeof(username), FALSE)) { /* @@ -4034,7 +4043,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) static int tried_pubkey_config, tried_agent, tried_keyb_inter; static int kbd_inter_running; static int we_are_in; - static int num_prompts, echo; + static int num_prompts, curr_prompt, echo; static char username[100]; static int got_username; static char pwprompt[200]; @@ -4097,7 +4106,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) * it again. */ } else if ((flags & FLAG_INTERACTIVE) && !*cfg.username) { - if (ssh_get_line) { + if (ssh_get_line && !ssh_getline_pw_only) { if (!ssh_get_line("login as: ", username, sizeof(username), FALSE)) { /* @@ -4235,9 +4244,14 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) if (kbd_inter_running && pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) { /* - * This is a further prompt in keyboard-interactive - * authentication. Do nothing. + * This is either a further set-of-prompts packet + * in keyboard-interactive authentication, or it's + * the same one and we came back here with `gotit' + * set. In the former case, we must reset the + * curr_prompt variable. */ + if (!gotit) + curr_prompt = 0; } else if (pktin.type != SSH2_MSG_USERAUTH_FAILURE) { bombout(("Strange packet received during authentication: type %d", pktin.type)); @@ -4321,6 +4335,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) static int authed = FALSE; void *r; + ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK; ssh_pkt_ctx |= SSH2_PKTCTX_PUBLICKEY; tried_agent = TRUE; @@ -4463,6 +4478,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) tried_pubkey_config = TRUE; + ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK; ssh_pkt_ctx |= SSH2_PKTCTX_PUBLICKEY; /* @@ -4517,6 +4533,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) type = AUTH_TYPE_KEYBOARD_INTERACTIVE; tried_keyb_inter = TRUE; + ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK; ssh_pkt_ctx |= SSH2_PKTCTX_KBDINTER; ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST); @@ -4537,6 +4554,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) } kbd_inter_running = TRUE; + curr_prompt = 0; } if (kbd_inter_running) { @@ -4544,34 +4562,58 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) type = AUTH_TYPE_KEYBOARD_INTERACTIVE; tried_keyb_inter = TRUE; + ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK; ssh_pkt_ctx |= SSH2_PKTCTX_KBDINTER; - /* We've got packet with that "interactive" info - dump banners, and set its prompt as ours */ - { - char *name, *inst, *lang, *prompt; - int name_len, inst_len, lang_len, prompt_len; + if (curr_prompt == 0) { + /* + * We've got a fresh USERAUTH_INFO_REQUEST. + * Display header data, and start going through + * the prompts. + */ + char *name, *inst, *lang; + int name_len, inst_len, lang_len; + ssh2_pkt_getstring(&name, &name_len); ssh2_pkt_getstring(&inst, &inst_len); ssh2_pkt_getstring(&lang, &lang_len); - if (name_len > 0) + if (name_len > 0) { c_write_untrusted(name, name_len); - if (inst_len > 0) + c_write_str("\n"); + } + if (inst_len > 0) { c_write_untrusted(inst, inst_len); + c_write_str("\n"); + } num_prompts = ssh2_pkt_getuint32(); + } - ssh2_pkt_getstring(&prompt, &prompt_len); - strncpy(pwprompt, prompt, sizeof(pwprompt)); - pwprompt[prompt_len < sizeof(pwprompt) ? - prompt_len : sizeof(pwprompt)-1] = '\0'; - need_pw = TRUE; + /* + * If there are prompts remaining in the packet, + * display one and get a response. + */ + if (curr_prompt < num_prompts) { + char *prompt; + int prompt_len; + ssh2_pkt_getstring(&prompt, &prompt_len); + if (prompt_len > 0) { + strncpy(pwprompt, prompt, sizeof(pwprompt)); + pwprompt[prompt_len < sizeof(pwprompt) ? + prompt_len : sizeof(pwprompt)-1] = '\0'; + } else { + strcpy(pwprompt, + ": "); + } echo = ssh2_pkt_getbool(); - } + need_pw = TRUE; + } else + need_pw = FALSE; } if (!method && can_passwd) { method = AUTH_PASSWORD; + ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK; ssh_pkt_ctx |= SSH2_PKTCTX_PASSWORD; sprintf(pwprompt, "%.90s@%.90s's password: ", username, savedhost); @@ -4763,11 +4805,28 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) logevent("Sent password"); type = AUTH_TYPE_PASSWORD; } else if (method == AUTH_KEYBOARD_INTERACTIVE) { - ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE); - ssh2_pkt_adduint32(num_prompts); - ssh2_pkt_addstring(password); - memset(password, 0, sizeof(password)); - ssh2_pkt_send(); + if (curr_prompt == 0) { + ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE); + ssh2_pkt_adduint32(num_prompts); + } + if (need_pw) { /* only add pw if we just got one! */ + ssh2_pkt_addstring(password); + memset(password, 0, sizeof(password)); + curr_prompt++; + } + if (curr_prompt >= num_prompts) { + ssh2_pkt_send(); + } else { + /* + * If there are prompts remaining, we set + * `gotit' so that we won't attempt to get + * another packet. Then we go back round the + * loop and will end up retrieving another + * prompt out of the existing packet. Funky or + * what? + */ + gotit = TRUE; + } type = AUTH_TYPE_KEYBOARD_INTERACTIVE; } else { c_write_str @@ -5357,7 +5416,6 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt) c->type = CHAN_SOCKDATA; c->v.v2.remwindow = ssh2_pkt_getuint32(); c->v.v2.remmaxpkt = ssh2_pkt_getuint32(); - bufchain_init(&c->v.v2.outbuffer); if (c->u.pfd.s) pfd_confirm(c->u.pfd.s); if (c->closes) { @@ -5759,6 +5817,7 @@ void *new_sock_channel(Socket s) c->closes = 0; c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */ c->u.pfd.s = s; + bufchain_init(&c->v.v2.outbuffer); add234(ssh_channels, c); } return c;