20001205
- (bal) OpenSSH CVS updates:
- markus@cvs.openbsd.org 2000/12/04 19:24:02
[ssh-keyscan.c ssh-keyscan.1]
David Maziere's ssh-keyscan, ok niels@
- (bal) Updated Makefile.in to include ssh-keyscan that was just added
to the recent OpenBSD source tree.
diff --git a/ssh-keyscan.c b/ssh-keyscan.c
new file mode 100644
index 0000000..0b2ed40
--- /dev/null
+++ b/ssh-keyscan.c
@@ -0,0 +1,605 @@
+/*
+ * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>.
+ *
+ * Modification and redistribution in source and binary forms is
+ * permitted provided that due credit is given to the author and the
+ * OpenBSD project (for instance by leaving this copyright notice
+ * intact).
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: ssh-keyscan.c,v 1.1 2000/12/04 19:24:02 markus Exp $");
+
+#include <sys/queue.h>
+#include <err.h>
+#include <errno.h>
+
+#include <openssl/bn.h>
+#include <openssl/rsa.h>
+#include <openssl/dsa.h>
+
+#include "xmalloc.h"
+#include "ssh.h"
+#include "key.h"
+#include "buffer.h"
+#include "bufaux.h"
+
+static int argno = 1; /* Number of argument currently being parsed */
+
+int family = AF_UNSPEC; /* IPv4, IPv6 or both */
+
+#define PORT 22
+#define MAXMAXFD 256
+
+/* The number of seconds after which to give up on a TCP connection */
+int timeout = 5;
+
+int maxfd;
+#define maxcon (maxfd - 10)
+
+char *prog;
+fd_set read_wait;
+int ncon;
+
+/*
+ * Keep a connection structure for each file descriptor. The state
+ * associated with file descriptor n is held in fdcon[n].
+ */
+typedef struct Connection {
+ unsigned char c_status; /* State of connection on this file desc. */
+#define CS_UNUSED 0 /* File descriptor unused */
+#define CS_CON 1 /* Waiting to connect/read greeting */
+#define CS_SIZE 2 /* Waiting to read initial packet size */
+#define CS_KEYS 3 /* Waiting to read public key packet */
+ int c_fd; /* Quick lookup: c->c_fd == c - fdcon */
+ int c_plen; /* Packet length field for ssh packet */
+ int c_len; /* Total bytes which must be read. */
+ int c_off; /* Length of data read so far. */
+ char *c_namebase; /* Address to free for c_name and c_namelist */
+ char *c_name; /* Hostname of connection for errors */
+ char *c_namelist; /* Pointer to other possible addresses */
+ char *c_output_name; /* Hostname of connection for output */
+ char *c_data; /* Data read from this fd */
+ struct timeval c_tv; /* Time at which connection gets aborted */
+ TAILQ_ENTRY(Connection) c_link; /* List of connections in timeout order. */
+} con;
+
+TAILQ_HEAD(conlist, Connection) tq; /* Timeout Queue */
+con *fdcon;
+
+/*
+ * This is just a wrapper around fgets() to make it usable.
+ */
+
+/* Stress-test. Increase this later. */
+#define LINEBUF_SIZE 16
+
+typedef struct {
+ char *buf;
+ unsigned int size;
+ int lineno;
+ const char *filename;
+ FILE *stream;
+ void (*errfun) (const char *,...);
+} Linebuf;
+
+static inline Linebuf *
+Linebuf_alloc(const char *filename, void (*errfun) (const char *,...))
+{
+ Linebuf *lb;
+
+ if (!(lb = malloc(sizeof(*lb)))) {
+ if (errfun)
+ (*errfun) ("linebuf (%s): malloc failed\n", lb->filename);
+ return (NULL);
+ }
+ if (filename) {
+ lb->filename = filename;
+ if (!(lb->stream = fopen(filename, "r"))) {
+ free(lb);
+ if (errfun)
+ (*errfun) ("%s: %s\n", filename, strerror(errno));
+ return (NULL);
+ }
+ } else {
+ lb->filename = "(stdin)";
+ lb->stream = stdin;
+ }
+
+ if (!(lb->buf = malloc(lb->size = LINEBUF_SIZE))) {
+ if (errfun)
+ (*errfun) ("linebuf (%s): malloc failed\n", lb->filename);
+ free(lb);
+ return (NULL);
+ }
+ lb->errfun = errfun;
+ lb->lineno = 0;
+ return (lb);
+}
+
+static inline void
+Linebuf_free(Linebuf * lb)
+{
+ fclose(lb->stream);
+ free(lb->buf);
+ free(lb);
+}
+
+static inline void
+Linebuf_restart(Linebuf * lb)
+{
+ clearerr(lb->stream);
+ rewind(lb->stream);
+ lb->lineno = 0;
+}
+
+static inline int
+Linebuf_lineno(Linebuf * lb)
+{
+ return (lb->lineno);
+}
+
+static inline char *
+getline(Linebuf * lb)
+{
+ int n = 0;
+
+ lb->lineno++;
+ for (;;) {
+ /* Read a line */
+ if (!fgets(&lb->buf[n], lb->size - n, lb->stream)) {
+ if (ferror(lb->stream) && lb->errfun)
+ (*lb->errfun) ("%s: %s\n", lb->filename, strerror(errno));
+ return (NULL);
+ }
+ n = strlen(lb->buf);
+
+ /* Return it or an error if it fits */
+ if (n > 0 && lb->buf[n - 1] == '\n') {
+ lb->buf[n - 1] = '\0';
+ return (lb->buf);
+ }
+ if (n != lb->size - 1) {
+ if (lb->errfun)
+ (*lb->errfun) ("%s: skipping incomplete last line\n", lb->filename);
+ return (NULL);
+ }
+ /* Double the buffer if we need more space */
+ if (!(lb->buf = realloc(lb->buf, (lb->size *= 2)))) {
+ if (lb->errfun)
+ (*lb->errfun) ("linebuf (%s): realloc failed\n", lb->filename);
+ return (NULL);
+ }
+ }
+}
+
+static int
+fdlim_get(int hard)
+{
+ struct rlimit rlfd;
+ if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0)
+ return (-1);
+ if ((hard ? rlfd.rlim_max : rlfd.rlim_cur) == RLIM_INFINITY)
+ return 10000;
+ else
+ return hard ? rlfd.rlim_max : rlfd.rlim_cur;
+}
+
+static int
+fdlim_set(int lim)
+{
+ struct rlimit rlfd;
+ if (lim <= 0)
+ return (-1);
+ if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0)
+ return (-1);
+ rlfd.rlim_cur = lim;
+ if (setrlimit(RLIMIT_NOFILE, &rlfd) < 0)
+ return (-1);
+ return (0);
+}
+
+/*
+ * This is an strsep function that returns a null field for adjacent
+ * separators. This is the same as the 4.4BSD strsep, but different from the
+ * one in the GNU libc.
+ */
+inline char *
+xstrsep(char **str, const char *delim)
+{
+ char *s, *e;
+
+ if (!**str)
+ return (NULL);
+
+ s = *str;
+ e = s + strcspn(s, delim);
+
+ if (*e != '\0')
+ *e++ = '\0';
+ *str = e;
+
+ return (s);
+}
+
+/*
+ * Get the next non-null token (like GNU strsep). Strsep() will return a
+ * null token for two adjacent separators, so we may have to loop.
+ */
+char *
+strnnsep(char **stringp, char *delim)
+{
+ char *tok;
+
+ do {
+ tok = xstrsep(stringp, delim);
+ } while (tok && *tok == '\0');
+ return (tok);
+}
+
+void
+keyprint(char *host, char *output_name, char *kd, int len)
+{
+ static Key *rsa;
+ static Buffer msg;
+
+ if (rsa == NULL) {
+ buffer_init(&msg);
+ rsa = key_new(KEY_RSA1);
+ }
+ buffer_append(&msg, kd, len);
+ buffer_consume(&msg, 8 - (len & 7)); /* padding */
+ if (buffer_get_char(&msg) != (int) SSH_SMSG_PUBLIC_KEY) {
+ error("%s: invalid packet type", host);
+ buffer_clear(&msg);
+ return;
+ }
+ buffer_consume(&msg, 8); /* cookie */
+
+ /* server key */
+ (void) buffer_get_int(&msg);
+ buffer_get_bignum(&msg, rsa->rsa->e);
+ buffer_get_bignum(&msg, rsa->rsa->n);
+
+ /* host key */
+ (void) buffer_get_int(&msg);
+ buffer_get_bignum(&msg, rsa->rsa->e);
+ buffer_get_bignum(&msg, rsa->rsa->n);
+ buffer_clear(&msg);
+
+ fprintf(stdout, "%s ", output_name ? output_name : host);
+ key_write(rsa, stdout);
+ fputs("\n", stdout);
+}
+
+int
+tcpconnect(char *host)
+{
+ struct addrinfo hints, *ai, *aitop;
+ char strport[NI_MAXSERV];
+ int gaierr, s = -1;
+
+ snprintf(strport, sizeof strport, "%d", PORT);
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = family;
+ hints.ai_socktype = SOCK_STREAM;
+ if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0)
+ fatal("getaddrinfo %s: %s", host, gai_strerror(gaierr));
+ for (ai = aitop; ai; ai = ai->ai_next) {
+ s = socket(ai->ai_family, SOCK_STREAM, 0);
+ if (s < 0) {
+ error("socket: %s", strerror(errno));
+ continue;
+ }
+ if (fcntl(s, F_SETFL, O_NDELAY) < 0)
+ fatal("F_SETFL: %s", strerror(errno));
+ if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0 &&
+ errno != EINPROGRESS)
+ error("connect (`%s'): %s", host, strerror(errno));
+ else
+ break;
+ close(s);
+ s = -1;
+ }
+ freeaddrinfo(aitop);
+ return s;
+}
+
+int
+conalloc(char *iname, char *oname)
+{
+ int s;
+ char *namebase, *name, *namelist;
+
+ namebase = namelist = xstrdup(iname);
+
+ do {
+ name = xstrsep(&namelist, ",");
+ if (!name) {
+ free(namebase);
+ return (-1);
+ }
+ } while ((s = tcpconnect(name)) < 0);
+
+ if (s >= maxfd)
+ fatal("conalloc: fdno %d too high\n", s);
+ if (fdcon[s].c_status)
+ fatal("conalloc: attempt to reuse fdno %d\n", s);
+
+ fdcon[s].c_fd = s;
+ fdcon[s].c_status = CS_CON;
+ fdcon[s].c_namebase = namebase;
+ fdcon[s].c_name = name;
+ fdcon[s].c_namelist = namelist;
+ fdcon[s].c_output_name = xstrdup(oname);
+ fdcon[s].c_data = (char *) &fdcon[s].c_plen;
+ fdcon[s].c_len = 4;
+ fdcon[s].c_off = 0;
+ gettimeofday(&fdcon[s].c_tv, NULL);
+ fdcon[s].c_tv.tv_sec += timeout;
+ TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link);
+ FD_SET(s, &read_wait);
+ ncon++;
+ return (s);
+}
+
+void
+confree(int s)
+{
+ close(s);
+ if (s >= maxfd || fdcon[s].c_status == CS_UNUSED)
+ fatal("confree: attempt to free bad fdno %d\n", s);
+ free(fdcon[s].c_namebase);
+ free(fdcon[s].c_output_name);
+ if (fdcon[s].c_status == CS_KEYS)
+ free(fdcon[s].c_data);
+ fdcon[s].c_status = CS_UNUSED;
+ TAILQ_REMOVE(&tq, &fdcon[s], c_link);
+ FD_CLR(s, &read_wait);
+ ncon--;
+}
+
+void
+contouch(int s)
+{
+ TAILQ_REMOVE(&tq, &fdcon[s], c_link);
+ gettimeofday(&fdcon[s].c_tv, NULL);
+ fdcon[s].c_tv.tv_sec += timeout;
+ TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link);
+}
+
+int
+conrecycle(int s)
+{
+ int ret;
+ con *c = &fdcon[s];
+ char *iname, *oname;
+
+ iname = xstrdup(c->c_namelist);
+ oname = c->c_output_name;
+ c->c_output_name = NULL;/* prevent it from being freed */
+ confree(s);
+ ret = conalloc(iname, oname);
+ free(iname);
+ return (ret);
+}
+
+void
+congreet(int s)
+{
+ char buf[80];
+ int n;
+ con *c = &fdcon[s];
+
+ n = read(s, buf, sizeof(buf));
+ if (n < 0) {
+ if (errno != ECONNREFUSED)
+ error("read (%s): %s", c->c_name, strerror(errno));
+ conrecycle(s);
+ return;
+ }
+ if (buf[n - 1] != '\n') {
+ error("%s: bad greeting", c->c_name);
+ confree(s);
+ return;
+ }
+ buf[n - 1] = '\0';
+ fprintf(stderr, "# %s %s\n", c->c_name, buf);
+ n = snprintf(buf, sizeof buf, "SSH-1.5-OpenSSH-keyscan\r\n");
+ if (write(s, buf, n) != n) {
+ error("write (%s): %s", c->c_name, strerror(errno));
+ confree(s);
+ return;
+ }
+ c->c_status = CS_SIZE;
+ contouch(s);
+}
+
+void
+conread(int s)
+{
+ int n;
+ con *c = &fdcon[s];
+
+ if (c->c_status == CS_CON) {
+ congreet(s);
+ return;
+ }
+ n = read(s, c->c_data + c->c_off, c->c_len - c->c_off);
+ if (n < 0) {
+ error("read (%s): %s", c->c_name, strerror(errno));
+ confree(s);
+ return;
+ }
+ c->c_off += n;
+
+ if (c->c_off == c->c_len)
+ switch (c->c_status) {
+ case CS_SIZE:
+ c->c_plen = htonl(c->c_plen);
+ c->c_len = c->c_plen + 8 - (c->c_plen & 7);
+ c->c_off = 0;
+ c->c_data = xmalloc(c->c_len);
+ c->c_status = CS_KEYS;
+ break;
+ case CS_KEYS:
+ keyprint(c->c_name, c->c_output_name, c->c_data, c->c_plen);
+ confree(s);
+ return;
+ break;
+ default:
+ fatal("conread: invalid status %d\n", c->c_status);
+ break;
+ }
+
+ contouch(s);
+}
+
+void
+conloop(void)
+{
+ fd_set r, e;
+ struct timeval seltime, now;
+ int i;
+ con *c;
+
+ gettimeofday(&now, NULL);
+ c = tq.tqh_first;
+
+ if (c &&
+ (c->c_tv.tv_sec > now.tv_sec ||
+ (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec > now.tv_usec))) {
+ seltime = c->c_tv;
+ seltime.tv_sec -= now.tv_sec;
+ seltime.tv_usec -= now.tv_usec;
+ if ((int) seltime.tv_usec < 0) {
+ seltime.tv_usec += 1000000;
+ seltime.tv_sec--;
+ }
+ } else
+ seltime.tv_sec = seltime.tv_usec = 0;
+
+ r = e = read_wait;
+ select(maxfd, &r, NULL, &e, &seltime);
+ for (i = 0; i < maxfd; i++)
+ if (FD_ISSET(i, &e)) {
+ error("%s: exception!", fdcon[i].c_name);
+ confree(i);
+ } else if (FD_ISSET(i, &r))
+ conread(i);
+
+ c = tq.tqh_first;
+ while (c &&
+ (c->c_tv.tv_sec < now.tv_sec ||
+ (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec < now.tv_usec))) {
+ int s = c->c_fd;
+ c = c->c_link.tqe_next;
+ conrecycle(s);
+ }
+}
+
+char *
+nexthost(int argc, char **argv)
+{
+ static Linebuf *lb;
+
+ for (;;) {
+ if (!lb) {
+ if (argno >= argc)
+ return (NULL);
+ if (argv[argno][0] != '-')
+ return (argv[argno++]);
+ if (!strcmp(argv[argno], "--")) {
+ if (++argno >= argc)
+ return (NULL);
+ return (argv[argno++]);
+ } else if (!strncmp(argv[argno], "-f", 2)) {
+ char *fname;
+ if (argv[argno][2])
+ fname = &argv[argno++][2];
+ else if (++argno >= argc) {
+ error("missing filename for `-f'");
+ return (NULL);
+ } else
+ fname = argv[argno++];
+ if (!strcmp(fname, "-"))
+ fname = NULL;
+ lb = Linebuf_alloc(fname, warn);
+ } else
+ error("ignoring invalid/misplaced option `%s'", argv[argno++]);
+ } else {
+ char *line;
+ line = getline(lb);
+ if (line)
+ return (line);
+ Linebuf_free(lb);
+ lb = NULL;
+ }
+ }
+}
+
+static void
+usage(void)
+{
+ fatal("usage: %s [-t timeout] { [--] host | -f file } ...\n", prog);
+ return;
+}
+
+int
+main(int argc, char **argv)
+{
+ char *host = NULL;
+
+ TAILQ_INIT(&tq);
+
+ if ((prog = strrchr(argv[0], '/')))
+ prog++;
+ else
+ prog = argv[0];
+
+ if (argc <= argno)
+ usage();
+
+ if (argv[1][0] == '-' && argv[1][1] == 't') {
+ argno++;
+ if (argv[1][2])
+ timeout = atoi(&argv[1][2]);
+ else {
+ if (argno >= argc)
+ usage();
+ timeout = atoi(argv[argno++]);
+ }
+ if (timeout <= 0)
+ usage();
+ }
+ if (argc <= argno)
+ usage();
+
+ maxfd = fdlim_get(1);
+ if (maxfd < 0)
+ fatal("%s: fdlim_get: bad value\n", prog);
+ if (maxfd > MAXMAXFD)
+ maxfd = MAXMAXFD;
+ if (maxcon <= 0)
+ fatal("%s: not enough file descriptors\n", prog);
+ if (maxfd > fdlim_get(0))
+ fdlim_set(maxfd);
+ fdcon = xmalloc(maxfd * sizeof(con));
+
+ do {
+ while (ncon < maxcon) {
+ char *name;
+
+ host = nexthost(argc, argv);
+ if (host == NULL)
+ break;
+ name = strnnsep(&host, " \t\n");
+ conalloc(name, *host ? host : name);
+ }
+ conloop();
+ } while (host);
+ while (ncon > 0)
+ conloop();
+
+ return (0);
+}