ssh-keyscan.c revision 157019
176259Sgreen/* 276259Sgreen * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>. 376259Sgreen * 476259Sgreen * Modification and redistribution in source and binary forms is 576259Sgreen * permitted provided that due credit is given to the author and the 692555Sdes * OpenBSD project by leaving this copyright notice intact. 776259Sgreen */ 876259Sgreen 976259Sgreen#include "includes.h" 10157019SdesRCSID("$OpenBSD: ssh-keyscan.c,v 1.57 2005/10/30 04:01:03 djm Exp $"); 1176259Sgreen 12106130Sdes#include "openbsd-compat/sys-queue.h" 1376259Sgreen 1476259Sgreen#include <openssl/bn.h> 1576259Sgreen 1692555Sdes#include <setjmp.h> 1776259Sgreen#include "xmalloc.h" 1876259Sgreen#include "ssh.h" 1976259Sgreen#include "ssh1.h" 2076259Sgreen#include "key.h" 2192555Sdes#include "kex.h" 2292555Sdes#include "compat.h" 2392555Sdes#include "myproposal.h" 2492555Sdes#include "packet.h" 2592555Sdes#include "dispatch.h" 2676259Sgreen#include "buffer.h" 2776259Sgreen#include "bufaux.h" 2876259Sgreen#include "log.h" 2976259Sgreen#include "atomicio.h" 3092555Sdes#include "misc.h" 31147005Sdes#include "hostfile.h" 3276259Sgreen 3398941Sdes/* Flag indicating whether IPv4 or IPv6. This can be set on the command line. 3498941Sdes Default value is AF_UNSPEC means both IPv4 and IPv6. */ 3598941Sdesint IPv4or6 = AF_UNSPEC; 3676259Sgreen 3792555Sdesint ssh_port = SSH_DEFAULT_PORT; 3876259Sgreen 3992555Sdes#define KT_RSA1 1 4092555Sdes#define KT_DSA 2 4192555Sdes#define KT_RSA 4 4292555Sdes 4392555Sdesint get_keytypes = KT_RSA1; /* Get only RSA1 keys by default */ 4492555Sdes 45147005Sdesint hash_hosts = 0; /* Hash hostname on output */ 46147005Sdes 4776259Sgreen#define MAXMAXFD 256 4876259Sgreen 4976259Sgreen/* The number of seconds after which to give up on a TCP connection */ 5076259Sgreenint timeout = 5; 5176259Sgreen 5276259Sgreenint maxfd; 5376259Sgreen#define MAXCON (maxfd - 10) 5476259Sgreen 5576259Sgreenextern char *__progname; 5676259Sgreenfd_set *read_wait; 5776259Sgreensize_t read_wait_size; 5876259Sgreenint ncon; 5992555Sdesint nonfatal_fatal = 0; 6092555Sdesjmp_buf kexjmp; 6192555SdesKey *kexjmp_key; 6276259Sgreen 6376259Sgreen/* 6476259Sgreen * Keep a connection structure for each file descriptor. The state 6576259Sgreen * associated with file descriptor n is held in fdcon[n]. 6676259Sgreen */ 6776259Sgreentypedef struct Connection { 6876259Sgreen u_char c_status; /* State of connection on this file desc. */ 6976259Sgreen#define CS_UNUSED 0 /* File descriptor unused */ 7076259Sgreen#define CS_CON 1 /* Waiting to connect/read greeting */ 7176259Sgreen#define CS_SIZE 2 /* Waiting to read initial packet size */ 7276259Sgreen#define CS_KEYS 3 /* Waiting to read public key packet */ 7376259Sgreen int c_fd; /* Quick lookup: c->c_fd == c - fdcon */ 7476259Sgreen int c_plen; /* Packet length field for ssh packet */ 7576259Sgreen int c_len; /* Total bytes which must be read. */ 7676259Sgreen int c_off; /* Length of data read so far. */ 7792555Sdes int c_keytype; /* Only one of KT_RSA1, KT_DSA, or KT_RSA */ 7876259Sgreen char *c_namebase; /* Address to free for c_name and c_namelist */ 7976259Sgreen char *c_name; /* Hostname of connection for errors */ 8076259Sgreen char *c_namelist; /* Pointer to other possible addresses */ 8176259Sgreen char *c_output_name; /* Hostname of connection for output */ 8276259Sgreen char *c_data; /* Data read from this fd */ 8392555Sdes Kex *c_kex; /* The key-exchange struct for ssh2 */ 8476259Sgreen struct timeval c_tv; /* Time at which connection gets aborted */ 8576259Sgreen TAILQ_ENTRY(Connection) c_link; /* List of connections in timeout order. */ 8676259Sgreen} con; 8776259Sgreen 8876259SgreenTAILQ_HEAD(conlist, Connection) tq; /* Timeout Queue */ 8976259Sgreencon *fdcon; 9076259Sgreen 9176259Sgreen/* 9276259Sgreen * This is just a wrapper around fgets() to make it usable. 9376259Sgreen */ 9476259Sgreen 9576259Sgreen/* Stress-test. Increase this later. */ 9676259Sgreen#define LINEBUF_SIZE 16 9776259Sgreen 9876259Sgreentypedef struct { 9976259Sgreen char *buf; 10076259Sgreen u_int size; 10176259Sgreen int lineno; 10276259Sgreen const char *filename; 10376259Sgreen FILE *stream; 10476259Sgreen void (*errfun) (const char *,...); 10576259Sgreen} Linebuf; 10676259Sgreen 10792555Sdesstatic Linebuf * 10876259SgreenLinebuf_alloc(const char *filename, void (*errfun) (const char *,...)) 10976259Sgreen{ 11076259Sgreen Linebuf *lb; 11176259Sgreen 11276259Sgreen if (!(lb = malloc(sizeof(*lb)))) { 11376259Sgreen if (errfun) 114106130Sdes (*errfun) ("linebuf (%s): malloc failed\n", 115106130Sdes filename ? filename : "(stdin)"); 11676259Sgreen return (NULL); 11776259Sgreen } 11876259Sgreen if (filename) { 11976259Sgreen lb->filename = filename; 12076259Sgreen if (!(lb->stream = fopen(filename, "r"))) { 12176259Sgreen xfree(lb); 12276259Sgreen if (errfun) 12376259Sgreen (*errfun) ("%s: %s\n", filename, strerror(errno)); 12476259Sgreen return (NULL); 12576259Sgreen } 12676259Sgreen } else { 12776259Sgreen lb->filename = "(stdin)"; 12876259Sgreen lb->stream = stdin; 12976259Sgreen } 13076259Sgreen 13176259Sgreen if (!(lb->buf = malloc(lb->size = LINEBUF_SIZE))) { 13276259Sgreen if (errfun) 13376259Sgreen (*errfun) ("linebuf (%s): malloc failed\n", lb->filename); 13476259Sgreen xfree(lb); 13576259Sgreen return (NULL); 13676259Sgreen } 13776259Sgreen lb->errfun = errfun; 13876259Sgreen lb->lineno = 0; 13976259Sgreen return (lb); 14076259Sgreen} 14176259Sgreen 14292555Sdesstatic void 14376259SgreenLinebuf_free(Linebuf * lb) 14476259Sgreen{ 14576259Sgreen fclose(lb->stream); 14676259Sgreen xfree(lb->buf); 14776259Sgreen xfree(lb); 14876259Sgreen} 14976259Sgreen 15092555Sdes#if 0 15192555Sdesstatic void 15276259SgreenLinebuf_restart(Linebuf * lb) 15376259Sgreen{ 15476259Sgreen clearerr(lb->stream); 15576259Sgreen rewind(lb->stream); 15676259Sgreen lb->lineno = 0; 15776259Sgreen} 15876259Sgreen 15992555Sdesstatic int 16076259SgreenLinebuf_lineno(Linebuf * lb) 16176259Sgreen{ 16276259Sgreen return (lb->lineno); 16376259Sgreen} 16492555Sdes#endif 16576259Sgreen 16692555Sdesstatic char * 16776259SgreenLinebuf_getline(Linebuf * lb) 16876259Sgreen{ 169149753Sdes size_t n = 0; 170106130Sdes void *p; 17176259Sgreen 17276259Sgreen lb->lineno++; 17376259Sgreen for (;;) { 17476259Sgreen /* Read a line */ 17576259Sgreen if (!fgets(&lb->buf[n], lb->size - n, lb->stream)) { 17676259Sgreen if (ferror(lb->stream) && lb->errfun) 177106130Sdes (*lb->errfun)("%s: %s\n", lb->filename, 17876259Sgreen strerror(errno)); 17976259Sgreen return (NULL); 18076259Sgreen } 18176259Sgreen n = strlen(lb->buf); 18276259Sgreen 18376259Sgreen /* Return it or an error if it fits */ 18476259Sgreen if (n > 0 && lb->buf[n - 1] == '\n') { 18576259Sgreen lb->buf[n - 1] = '\0'; 18676259Sgreen return (lb->buf); 18776259Sgreen } 18876259Sgreen if (n != lb->size - 1) { 18976259Sgreen if (lb->errfun) 190106130Sdes (*lb->errfun)("%s: skipping incomplete last line\n", 19176259Sgreen lb->filename); 19276259Sgreen return (NULL); 19376259Sgreen } 19476259Sgreen /* Double the buffer if we need more space */ 195106130Sdes lb->size *= 2; 196106130Sdes if ((p = realloc(lb->buf, lb->size)) == NULL) { 197106130Sdes lb->size /= 2; 19876259Sgreen if (lb->errfun) 199106130Sdes (*lb->errfun)("linebuf (%s): realloc failed\n", 20076259Sgreen lb->filename); 20176259Sgreen return (NULL); 20276259Sgreen } 203106130Sdes lb->buf = p; 20476259Sgreen } 20576259Sgreen} 20676259Sgreen 20792555Sdesstatic int 20876259Sgreenfdlim_get(int hard) 20976259Sgreen{ 21098941Sdes#if defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE) 21176259Sgreen struct rlimit rlfd; 21276259Sgreen 21376259Sgreen if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0) 21476259Sgreen return (-1); 21576259Sgreen if ((hard ? rlfd.rlim_max : rlfd.rlim_cur) == RLIM_INFINITY) 216126277Sdes return SSH_SYSFDMAX; 21776259Sgreen else 21876259Sgreen return hard ? rlfd.rlim_max : rlfd.rlim_cur; 21998941Sdes#else 220126277Sdes return SSH_SYSFDMAX; 22198941Sdes#endif 22276259Sgreen} 22376259Sgreen 22492555Sdesstatic int 22576259Sgreenfdlim_set(int lim) 22676259Sgreen{ 22798941Sdes#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_NOFILE) 22876259Sgreen struct rlimit rlfd; 22998941Sdes#endif 230106130Sdes 23176259Sgreen if (lim <= 0) 23276259Sgreen return (-1); 23398941Sdes#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_NOFILE) 23476259Sgreen if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0) 23576259Sgreen return (-1); 23676259Sgreen rlfd.rlim_cur = lim; 23776259Sgreen if (setrlimit(RLIMIT_NOFILE, &rlfd) < 0) 23876259Sgreen return (-1); 23998941Sdes#elif defined (HAVE_SETDTABLESIZE) 24098941Sdes setdtablesize(lim); 24198941Sdes#endif 24276259Sgreen return (0); 24376259Sgreen} 24476259Sgreen 24576259Sgreen/* 24676259Sgreen * This is an strsep function that returns a null field for adjacent 24776259Sgreen * separators. This is the same as the 4.4BSD strsep, but different from the 24876259Sgreen * one in the GNU libc. 24976259Sgreen */ 25092555Sdesstatic char * 25176259Sgreenxstrsep(char **str, const char *delim) 25276259Sgreen{ 25376259Sgreen char *s, *e; 25476259Sgreen 25576259Sgreen if (!**str) 25676259Sgreen return (NULL); 25776259Sgreen 25876259Sgreen s = *str; 25976259Sgreen e = s + strcspn(s, delim); 26076259Sgreen 26176259Sgreen if (*e != '\0') 26276259Sgreen *e++ = '\0'; 26376259Sgreen *str = e; 26476259Sgreen 26576259Sgreen return (s); 26676259Sgreen} 26776259Sgreen 26876259Sgreen/* 26976259Sgreen * Get the next non-null token (like GNU strsep). Strsep() will return a 27076259Sgreen * null token for two adjacent separators, so we may have to loop. 27176259Sgreen */ 27292555Sdesstatic char * 27376259Sgreenstrnnsep(char **stringp, char *delim) 27476259Sgreen{ 27576259Sgreen char *tok; 27676259Sgreen 27776259Sgreen do { 27876259Sgreen tok = xstrsep(stringp, delim); 27976259Sgreen } while (tok && *tok == '\0'); 28076259Sgreen return (tok); 28176259Sgreen} 28276259Sgreen 28392555Sdesstatic Key * 28492555Sdeskeygrab_ssh1(con *c) 28576259Sgreen{ 28676259Sgreen static Key *rsa; 28776259Sgreen static Buffer msg; 28876259Sgreen 28976259Sgreen if (rsa == NULL) { 29076259Sgreen buffer_init(&msg); 29176259Sgreen rsa = key_new(KEY_RSA1); 29276259Sgreen } 29392555Sdes buffer_append(&msg, c->c_data, c->c_plen); 29492555Sdes buffer_consume(&msg, 8 - (c->c_plen & 7)); /* padding */ 29576259Sgreen if (buffer_get_char(&msg) != (int) SSH_SMSG_PUBLIC_KEY) { 29692555Sdes error("%s: invalid packet type", c->c_name); 29776259Sgreen buffer_clear(&msg); 29892555Sdes return NULL; 29976259Sgreen } 30076259Sgreen buffer_consume(&msg, 8); /* cookie */ 30176259Sgreen 30276259Sgreen /* server key */ 30376259Sgreen (void) buffer_get_int(&msg); 30476259Sgreen buffer_get_bignum(&msg, rsa->rsa->e); 30576259Sgreen buffer_get_bignum(&msg, rsa->rsa->n); 30676259Sgreen 30776259Sgreen /* host key */ 30876259Sgreen (void) buffer_get_int(&msg); 30976259Sgreen buffer_get_bignum(&msg, rsa->rsa->e); 31076259Sgreen buffer_get_bignum(&msg, rsa->rsa->n); 31192555Sdes 31276259Sgreen buffer_clear(&msg); 31376259Sgreen 31492555Sdes return (rsa); 31592555Sdes} 31692555Sdes 31792555Sdesstatic int 31892555Sdeshostjump(Key *hostkey) 31992555Sdes{ 32092555Sdes kexjmp_key = hostkey; 32192555Sdes longjmp(kexjmp, 1); 32292555Sdes} 32392555Sdes 32492555Sdesstatic int 32592555Sdesssh2_capable(int remote_major, int remote_minor) 32692555Sdes{ 32792555Sdes switch (remote_major) { 32892555Sdes case 1: 32992555Sdes if (remote_minor == 99) 33092555Sdes return 1; 33192555Sdes break; 33292555Sdes case 2: 33392555Sdes return 1; 33492555Sdes default: 33592555Sdes break; 33692555Sdes } 33792555Sdes return 0; 33892555Sdes} 33992555Sdes 34092555Sdesstatic Key * 34192555Sdeskeygrab_ssh2(con *c) 34292555Sdes{ 34392555Sdes int j; 34492555Sdes 34592555Sdes packet_set_connection(c->c_fd, c->c_fd); 34692555Sdes enable_compat20(); 34792555Sdes myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = c->c_keytype == KT_DSA? 34892555Sdes "ssh-dss": "ssh-rsa"; 34992555Sdes c->c_kex = kex_setup(myproposal); 350113911Sdes c->c_kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client; 351137019Sdes c->c_kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client; 352113911Sdes c->c_kex->kex[KEX_DH_GEX_SHA1] = kexgex_client; 35392555Sdes c->c_kex->verify_host_key = hostjump; 35492555Sdes 35592555Sdes if (!(j = setjmp(kexjmp))) { 35692555Sdes nonfatal_fatal = 1; 35792555Sdes dispatch_run(DISPATCH_BLOCK, &c->c_kex->done, c->c_kex); 35892555Sdes fprintf(stderr, "Impossible! dispatch_run() returned!\n"); 35992555Sdes exit(1); 36092555Sdes } 36192555Sdes nonfatal_fatal = 0; 36292555Sdes xfree(c->c_kex); 36392555Sdes c->c_kex = NULL; 36492555Sdes packet_close(); 36592555Sdes 36692555Sdes return j < 0? NULL : kexjmp_key; 36792555Sdes} 36892555Sdes 36992555Sdesstatic void 37092555Sdeskeyprint(con *c, Key *key) 37192555Sdes{ 372147005Sdes char *host = c->c_output_name ? c->c_output_name : c->c_name; 373147005Sdes 37492555Sdes if (!key) 37592555Sdes return; 376147005Sdes if (hash_hosts && (host = host_hash(host, NULL, 0)) == NULL) 377147005Sdes fatal("host_hash failed"); 37892555Sdes 379147005Sdes fprintf(stdout, "%s ", host); 38092555Sdes key_write(key, stdout); 38176259Sgreen fputs("\n", stdout); 38276259Sgreen} 38376259Sgreen 38492555Sdesstatic int 38576259Sgreentcpconnect(char *host) 38676259Sgreen{ 38776259Sgreen struct addrinfo hints, *ai, *aitop; 38876259Sgreen char strport[NI_MAXSERV]; 38976259Sgreen int gaierr, s = -1; 39076259Sgreen 39192555Sdes snprintf(strport, sizeof strport, "%d", ssh_port); 39276259Sgreen memset(&hints, 0, sizeof(hints)); 39392555Sdes hints.ai_family = IPv4or6; 39476259Sgreen hints.ai_socktype = SOCK_STREAM; 39576259Sgreen if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) 39676259Sgreen fatal("getaddrinfo %s: %s", host, gai_strerror(gaierr)); 39776259Sgreen for (ai = aitop; ai; ai = ai->ai_next) { 398124211Sdes s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); 39976259Sgreen if (s < 0) { 40076259Sgreen error("socket: %s", strerror(errno)); 40176259Sgreen continue; 40276259Sgreen } 403137019Sdes if (set_nonblock(s) == -1) 404137019Sdes fatal("%s: set_nonblock(%d)", __func__, s); 40576259Sgreen if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0 && 40676259Sgreen errno != EINPROGRESS) 40776259Sgreen error("connect (`%s'): %s", host, strerror(errno)); 40876259Sgreen else 40976259Sgreen break; 41076259Sgreen close(s); 41176259Sgreen s = -1; 41276259Sgreen } 41376259Sgreen freeaddrinfo(aitop); 41476259Sgreen return s; 41576259Sgreen} 41676259Sgreen 41792555Sdesstatic int 41892555Sdesconalloc(char *iname, char *oname, int keytype) 41976259Sgreen{ 420106130Sdes char *namebase, *name, *namelist; 42176259Sgreen int s; 42276259Sgreen 42376259Sgreen namebase = namelist = xstrdup(iname); 42476259Sgreen 42576259Sgreen do { 42676259Sgreen name = xstrsep(&namelist, ","); 42776259Sgreen if (!name) { 42876259Sgreen xfree(namebase); 42976259Sgreen return (-1); 43076259Sgreen } 43176259Sgreen } while ((s = tcpconnect(name)) < 0); 43276259Sgreen 43376259Sgreen if (s >= maxfd) 43476259Sgreen fatal("conalloc: fdno %d too high", s); 43576259Sgreen if (fdcon[s].c_status) 43676259Sgreen fatal("conalloc: attempt to reuse fdno %d", s); 43776259Sgreen 43876259Sgreen fdcon[s].c_fd = s; 43976259Sgreen fdcon[s].c_status = CS_CON; 44076259Sgreen fdcon[s].c_namebase = namebase; 44176259Sgreen fdcon[s].c_name = name; 44276259Sgreen fdcon[s].c_namelist = namelist; 44376259Sgreen fdcon[s].c_output_name = xstrdup(oname); 44476259Sgreen fdcon[s].c_data = (char *) &fdcon[s].c_plen; 44576259Sgreen fdcon[s].c_len = 4; 44676259Sgreen fdcon[s].c_off = 0; 44792555Sdes fdcon[s].c_keytype = keytype; 44876259Sgreen gettimeofday(&fdcon[s].c_tv, NULL); 44976259Sgreen fdcon[s].c_tv.tv_sec += timeout; 45076259Sgreen TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link); 45176259Sgreen FD_SET(s, read_wait); 45276259Sgreen ncon++; 45376259Sgreen return (s); 45476259Sgreen} 45576259Sgreen 45692555Sdesstatic void 45776259Sgreenconfree(int s) 45876259Sgreen{ 45976259Sgreen if (s >= maxfd || fdcon[s].c_status == CS_UNUSED) 46076259Sgreen fatal("confree: attempt to free bad fdno %d", s); 46176259Sgreen close(s); 46276259Sgreen xfree(fdcon[s].c_namebase); 46376259Sgreen xfree(fdcon[s].c_output_name); 46476259Sgreen if (fdcon[s].c_status == CS_KEYS) 46576259Sgreen xfree(fdcon[s].c_data); 46676259Sgreen fdcon[s].c_status = CS_UNUSED; 46792555Sdes fdcon[s].c_keytype = 0; 46876259Sgreen TAILQ_REMOVE(&tq, &fdcon[s], c_link); 46976259Sgreen FD_CLR(s, read_wait); 47076259Sgreen ncon--; 47176259Sgreen} 47276259Sgreen 47392555Sdesstatic void 47476259Sgreencontouch(int s) 47576259Sgreen{ 47676259Sgreen TAILQ_REMOVE(&tq, &fdcon[s], c_link); 47776259Sgreen gettimeofday(&fdcon[s].c_tv, NULL); 47876259Sgreen fdcon[s].c_tv.tv_sec += timeout; 47976259Sgreen TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link); 48076259Sgreen} 48176259Sgreen 48292555Sdesstatic int 48376259Sgreenconrecycle(int s) 48476259Sgreen{ 485106130Sdes con *c = &fdcon[s]; 48676259Sgreen int ret; 48776259Sgreen 48892555Sdes ret = conalloc(c->c_namelist, c->c_output_name, c->c_keytype); 48976259Sgreen confree(s); 49076259Sgreen return (ret); 49176259Sgreen} 49276259Sgreen 49392555Sdesstatic void 49476259Sgreencongreet(int s) 49576259Sgreen{ 496149753Sdes int n = 0, remote_major = 0, remote_minor = 0; 49792555Sdes char buf[256], *cp; 49892555Sdes char remote_version[sizeof buf]; 49976259Sgreen size_t bufsiz; 50076259Sgreen con *c = &fdcon[s]; 50176259Sgreen 502157019Sdes for (;;) { 503157019Sdes memset(buf, '\0', sizeof(buf)); 504157019Sdes bufsiz = sizeof(buf); 505157019Sdes cp = buf; 506157019Sdes while (bufsiz-- && 507157019Sdes (n = atomicio(read, s, cp, 1)) == 1 && *cp != '\n') { 508157019Sdes if (*cp == '\r') 509157019Sdes *cp = '\n'; 510157019Sdes cp++; 511157019Sdes } 512157019Sdes if (n != 1 || strncmp(buf, "SSH-", 4) == 0) 513157019Sdes break; 51492555Sdes } 515149753Sdes if (n == 0) { 516149753Sdes switch (errno) { 517149753Sdes case EPIPE: 518149753Sdes error("%s: Connection closed by remote host", c->c_name); 519149753Sdes break; 520149753Sdes case ECONNREFUSED: 521149753Sdes break; 522149753Sdes default: 52376259Sgreen error("read (%s): %s", c->c_name, strerror(errno)); 524149753Sdes break; 525149753Sdes } 52676259Sgreen conrecycle(s); 52776259Sgreen return; 52876259Sgreen } 52976259Sgreen if (*cp != '\n' && *cp != '\r') { 53076259Sgreen error("%s: bad greeting", c->c_name); 53176259Sgreen confree(s); 53276259Sgreen return; 53376259Sgreen } 53476259Sgreen *cp = '\0'; 53592555Sdes if (sscanf(buf, "SSH-%d.%d-%[^\n]\n", 53692555Sdes &remote_major, &remote_minor, remote_version) == 3) 53792555Sdes compat_datafellows(remote_version); 53892555Sdes else 53992555Sdes datafellows = 0; 54092555Sdes if (c->c_keytype != KT_RSA1) { 54192555Sdes if (!ssh2_capable(remote_major, remote_minor)) { 54292555Sdes debug("%s doesn't support ssh2", c->c_name); 54392555Sdes confree(s); 54492555Sdes return; 54592555Sdes } 54692555Sdes } else if (remote_major != 1) { 54792555Sdes debug("%s doesn't support ssh1", c->c_name); 54892555Sdes confree(s); 54992555Sdes return; 55092555Sdes } 55192555Sdes fprintf(stderr, "# %s %s\n", c->c_name, chop(buf)); 55292555Sdes n = snprintf(buf, sizeof buf, "SSH-%d.%d-OpenSSH-keyscan\r\n", 55392555Sdes c->c_keytype == KT_RSA1? PROTOCOL_MAJOR_1 : PROTOCOL_MAJOR_2, 55492555Sdes c->c_keytype == KT_RSA1? PROTOCOL_MINOR_1 : PROTOCOL_MINOR_2); 555149753Sdes if (n < 0 || (size_t)n >= sizeof(buf)) { 556149753Sdes error("snprintf: buffer too small"); 557149753Sdes confree(s); 558149753Sdes return; 559149753Sdes } 560149753Sdes if (atomicio(vwrite, s, buf, n) != (size_t)n) { 56176259Sgreen error("write (%s): %s", c->c_name, strerror(errno)); 56276259Sgreen confree(s); 56376259Sgreen return; 56476259Sgreen } 56592555Sdes if (c->c_keytype != KT_RSA1) { 56692555Sdes keyprint(c, keygrab_ssh2(c)); 56792555Sdes confree(s); 56892555Sdes return; 56992555Sdes } 57076259Sgreen c->c_status = CS_SIZE; 57176259Sgreen contouch(s); 57276259Sgreen} 57376259Sgreen 57492555Sdesstatic void 57576259Sgreenconread(int s) 57676259Sgreen{ 577106130Sdes con *c = &fdcon[s]; 578149753Sdes size_t n; 57976259Sgreen 58076259Sgreen if (c->c_status == CS_CON) { 58176259Sgreen congreet(s); 58276259Sgreen return; 58376259Sgreen } 584137019Sdes n = atomicio(read, s, c->c_data + c->c_off, c->c_len - c->c_off); 585149753Sdes if (n == 0) { 58676259Sgreen error("read (%s): %s", c->c_name, strerror(errno)); 58776259Sgreen confree(s); 58876259Sgreen return; 58976259Sgreen } 59076259Sgreen c->c_off += n; 59176259Sgreen 59276259Sgreen if (c->c_off == c->c_len) 59376259Sgreen switch (c->c_status) { 59476259Sgreen case CS_SIZE: 59576259Sgreen c->c_plen = htonl(c->c_plen); 59676259Sgreen c->c_len = c->c_plen + 8 - (c->c_plen & 7); 59776259Sgreen c->c_off = 0; 59876259Sgreen c->c_data = xmalloc(c->c_len); 59976259Sgreen c->c_status = CS_KEYS; 60076259Sgreen break; 60176259Sgreen case CS_KEYS: 60292555Sdes keyprint(c, keygrab_ssh1(c)); 60376259Sgreen confree(s); 60476259Sgreen return; 60576259Sgreen break; 60676259Sgreen default: 60776259Sgreen fatal("conread: invalid status %d", c->c_status); 60876259Sgreen break; 60976259Sgreen } 61076259Sgreen 61176259Sgreen contouch(s); 61276259Sgreen} 61376259Sgreen 61492555Sdesstatic void 61576259Sgreenconloop(void) 61676259Sgreen{ 617106130Sdes struct timeval seltime, now; 61876259Sgreen fd_set *r, *e; 619106130Sdes con *c; 62076259Sgreen int i; 62176259Sgreen 62276259Sgreen gettimeofday(&now, NULL); 62398675Sdes c = TAILQ_FIRST(&tq); 62476259Sgreen 62576259Sgreen if (c && (c->c_tv.tv_sec > now.tv_sec || 62676259Sgreen (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec > now.tv_usec))) { 62776259Sgreen seltime = c->c_tv; 62876259Sgreen seltime.tv_sec -= now.tv_sec; 62976259Sgreen seltime.tv_usec -= now.tv_usec; 63076259Sgreen if (seltime.tv_usec < 0) { 63176259Sgreen seltime.tv_usec += 1000000; 63276259Sgreen seltime.tv_sec--; 63376259Sgreen } 63476259Sgreen } else 63576259Sgreen seltime.tv_sec = seltime.tv_usec = 0; 63676259Sgreen 63776259Sgreen r = xmalloc(read_wait_size); 63876259Sgreen memcpy(r, read_wait, read_wait_size); 63976259Sgreen e = xmalloc(read_wait_size); 64076259Sgreen memcpy(e, read_wait, read_wait_size); 64176259Sgreen 64276259Sgreen while (select(maxfd, r, NULL, e, &seltime) == -1 && 64376259Sgreen (errno == EAGAIN || errno == EINTR)) 64476259Sgreen ; 64576259Sgreen 64676259Sgreen for (i = 0; i < maxfd; i++) { 64776259Sgreen if (FD_ISSET(i, e)) { 64876259Sgreen error("%s: exception!", fdcon[i].c_name); 64976259Sgreen confree(i); 65076259Sgreen } else if (FD_ISSET(i, r)) 65176259Sgreen conread(i); 65276259Sgreen } 65376259Sgreen xfree(r); 65476259Sgreen xfree(e); 65576259Sgreen 65698675Sdes c = TAILQ_FIRST(&tq); 65776259Sgreen while (c && (c->c_tv.tv_sec < now.tv_sec || 65876259Sgreen (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec < now.tv_usec))) { 65976259Sgreen int s = c->c_fd; 66076259Sgreen 66198675Sdes c = TAILQ_NEXT(c, c_link); 66276259Sgreen conrecycle(s); 66376259Sgreen } 66476259Sgreen} 66576259Sgreen 66692555Sdesstatic void 66792555Sdesdo_host(char *host) 66876259Sgreen{ 66992555Sdes char *name = strnnsep(&host, " \t\n"); 67092555Sdes int j; 67176259Sgreen 67292555Sdes if (name == NULL) 67392555Sdes return; 67492555Sdes for (j = KT_RSA1; j <= KT_RSA; j *= 2) { 67592555Sdes if (get_keytypes & j) { 67692555Sdes while (ncon >= MAXCON) 67792555Sdes conloop(); 67892555Sdes conalloc(name, *host ? host : name, j); 67976259Sgreen } 68076259Sgreen } 68176259Sgreen} 68276259Sgreen 68376259Sgreenvoid 68492555Sdesfatal(const char *fmt,...) 68592555Sdes{ 68692555Sdes va_list args; 687106130Sdes 68892555Sdes va_start(args, fmt); 68992555Sdes do_log(SYSLOG_LEVEL_FATAL, fmt, args); 69092555Sdes va_end(args); 69192555Sdes if (nonfatal_fatal) 69292555Sdes longjmp(kexjmp, -1); 69392555Sdes else 694126277Sdes exit(255); 69592555Sdes} 69692555Sdes 69792555Sdesstatic void 69876259Sgreenusage(void) 69976259Sgreen{ 700147005Sdes fprintf(stderr, "usage: %s [-46Hv] [-f file] [-p port] [-T timeout] [-t type]\n" 701106130Sdes "\t\t [host | addrlist namelist] [...]\n", 70292555Sdes __progname); 70392555Sdes exit(1); 70476259Sgreen} 70576259Sgreen 70676259Sgreenint 70776259Sgreenmain(int argc, char **argv) 70876259Sgreen{ 70992555Sdes int debug_flag = 0, log_level = SYSLOG_LEVEL_INFO; 71092555Sdes int opt, fopt_count = 0; 71192555Sdes char *tname; 71276259Sgreen 71392555Sdes extern int optind; 71492555Sdes extern char *optarg; 71592555Sdes 716124211Sdes __progname = ssh_get_progname(argv[0]); 71798941Sdes init_rng(); 71898941Sdes seed_rng(); 71976259Sgreen TAILQ_INIT(&tq); 72076259Sgreen 721157019Sdes /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 722157019Sdes sanitise_stdfd(); 723157019Sdes 72492555Sdes if (argc <= 1) 72576259Sgreen usage(); 72676259Sgreen 727147005Sdes while ((opt = getopt(argc, argv, "Hv46p:T:t:f:")) != -1) { 72892555Sdes switch (opt) { 729147005Sdes case 'H': 730147005Sdes hash_hosts = 1; 731147005Sdes break; 73292555Sdes case 'p': 73392555Sdes ssh_port = a2port(optarg); 73492555Sdes if (ssh_port == 0) { 73592555Sdes fprintf(stderr, "Bad port '%s'\n", optarg); 73692555Sdes exit(1); 73792555Sdes } 73892555Sdes break; 73992555Sdes case 'T': 740106130Sdes timeout = convtime(optarg); 741106130Sdes if (timeout == -1 || timeout == 0) { 742106130Sdes fprintf(stderr, "Bad timeout '%s'\n", optarg); 74376259Sgreen usage(); 744106130Sdes } 74592555Sdes break; 74692555Sdes case 'v': 74792555Sdes if (!debug_flag) { 74892555Sdes debug_flag = 1; 74992555Sdes log_level = SYSLOG_LEVEL_DEBUG1; 75092555Sdes } 75192555Sdes else if (log_level < SYSLOG_LEVEL_DEBUG3) 75292555Sdes log_level++; 75392555Sdes else 75492555Sdes fatal("Too high debugging level."); 75592555Sdes break; 75692555Sdes case 'f': 75792555Sdes if (strcmp(optarg, "-") == 0) 75892555Sdes optarg = NULL; 75992555Sdes argv[fopt_count++] = optarg; 76092555Sdes break; 76192555Sdes case 't': 76292555Sdes get_keytypes = 0; 76392555Sdes tname = strtok(optarg, ","); 76492555Sdes while (tname) { 76592555Sdes int type = key_type_from_name(tname); 76692555Sdes switch (type) { 76792555Sdes case KEY_RSA1: 76892555Sdes get_keytypes |= KT_RSA1; 76992555Sdes break; 77092555Sdes case KEY_DSA: 77192555Sdes get_keytypes |= KT_DSA; 77292555Sdes break; 77392555Sdes case KEY_RSA: 77492555Sdes get_keytypes |= KT_RSA; 77592555Sdes break; 77692555Sdes case KEY_UNSPEC: 77792555Sdes fatal("unknown key type %s", tname); 77892555Sdes } 77992555Sdes tname = strtok(NULL, ","); 78092555Sdes } 78192555Sdes break; 78292555Sdes case '4': 78392555Sdes IPv4or6 = AF_INET; 78492555Sdes break; 78592555Sdes case '6': 78692555Sdes IPv4or6 = AF_INET6; 78792555Sdes break; 78892555Sdes case '?': 78992555Sdes default: 79092555Sdes usage(); 79176259Sgreen } 79276259Sgreen } 79392555Sdes if (optind == argc && !fopt_count) 79476259Sgreen usage(); 79576259Sgreen 79692555Sdes log_init("ssh-keyscan", log_level, SYSLOG_FACILITY_USER, 1); 79792555Sdes 79876259Sgreen maxfd = fdlim_get(1); 79976259Sgreen if (maxfd < 0) 80076259Sgreen fatal("%s: fdlim_get: bad value", __progname); 80176259Sgreen if (maxfd > MAXMAXFD) 80276259Sgreen maxfd = MAXMAXFD; 80376259Sgreen if (MAXCON <= 0) 80476259Sgreen fatal("%s: not enough file descriptors", __progname); 80576259Sgreen if (maxfd > fdlim_get(0)) 80676259Sgreen fdlim_set(maxfd); 80776259Sgreen fdcon = xmalloc(maxfd * sizeof(con)); 80876259Sgreen memset(fdcon, 0, maxfd * sizeof(con)); 80976259Sgreen 81076259Sgreen read_wait_size = howmany(maxfd, NFDBITS) * sizeof(fd_mask); 81176259Sgreen read_wait = xmalloc(read_wait_size); 81276259Sgreen memset(read_wait, 0, read_wait_size); 81376259Sgreen 81492555Sdes if (fopt_count) { 81592555Sdes Linebuf *lb; 81692555Sdes char *line; 81792555Sdes int j; 81876259Sgreen 81992555Sdes for (j = 0; j < fopt_count; j++) { 82092555Sdes lb = Linebuf_alloc(argv[j], error); 82192555Sdes if (!lb) 82292555Sdes continue; 82392555Sdes while ((line = Linebuf_getline(lb)) != NULL) 82492555Sdes do_host(line); 82592555Sdes Linebuf_free(lb); 82676259Sgreen } 82792555Sdes } 82892555Sdes 82992555Sdes while (optind < argc) 83092555Sdes do_host(argv[optind++]); 83192555Sdes 83276259Sgreen while (ncon > 0) 83376259Sgreen conloop(); 83476259Sgreen 83576259Sgreen return (0); 83676259Sgreen} 837