--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dbutil.c	Wed Mar 08 13:23:58 2006 +0000
@@ -0,0 +1,679 @@
+/*
+ * Dropbear - a SSH2 server
+ * 
+ * Copyright (c) 2002,2003 Matt Johnston
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * strlcat() is copyright as follows:
+ * Copyright (c) 1998 Todd C. Miller <[email protected]>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
+ * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
+
+#include "includes.h"
+#include "dbutil.h"
+#include "buffer.h"
+#include "session.h"
+#include "atomicio.h"
+
+#define MAX_FMT 100
+
+static void generic_dropbear_exit(int exitcode, const char* format, 
+		va_list param);
+static void generic_dropbear_log(int priority, const char* format, 
+		va_list param);
+
+void (*_dropbear_exit)(int exitcode, const char* format, va_list param) 
+						= generic_dropbear_exit;
+void (*_dropbear_log)(int priority, const char* format, va_list param)
+						= generic_dropbear_log;
+
+#ifdef DEBUG_TRACE
+int debug_trace = 0;
+#endif
+
+#ifndef DISABLE_SYSLOG
+void startsyslog() {
+
+	openlog(PROGNAME, LOG_PID, LOG_AUTHPRIV);
+
+}
+#endif /* DISABLE_SYSLOG */
+
+/* the "format" string must be <= 100 characters */
+void dropbear_close(const char* format, ...) {
+
+	va_list param;
+
+	va_start(param, format);
+	_dropbear_exit(EXIT_SUCCESS, format, param);
+	va_end(param);
+
+}
+
+void dropbear_exit(const char* format, ...) {
+
+	va_list param;
+
+	va_start(param, format);
+	_dropbear_exit(EXIT_FAILURE, format, param);
+	va_end(param);
+}
+
+static void generic_dropbear_exit(int exitcode, const char* format, 
+		va_list param) {
+
+	char fmtbuf[300];
+
+	snprintf(fmtbuf, sizeof(fmtbuf), "Exited: %s", format);
+
+	_dropbear_log(LOG_INFO, fmtbuf, param);
+
+	exit(exitcode);
+}
+
+void fail_assert(const char* expr, const char* file, int line) {
+	dropbear_exit("failed assertion (%s:%d): `%s'", file, line, expr);
+}
+
+static void generic_dropbear_log(int UNUSED(priority), const char* format, 
+		va_list param) {
+
+	char printbuf[1024];
+
+	vsnprintf(printbuf, sizeof(printbuf), format, param);
+
+	fprintf(stderr, "%s\n", printbuf);
+
+}
+
+/* this is what can be called to write arbitrary log messages */
+void dropbear_log(int priority, const char* format, ...) {
+
+	va_list param;
+
+	va_start(param, format);
+	_dropbear_log(priority, format, param);
+	va_end(param);
+}
+
+
+#ifdef DEBUG_TRACE
+void dropbear_trace(const char* format, ...) {
+
+	va_list param;
+
+	if (!debug_trace) {
+		return;
+	}
+
+	va_start(param, format);
+	fprintf(stderr, "TRACE: ");
+	vfprintf(stderr, format, param);
+	fprintf(stderr, "\n");
+	va_end(param);
+}
+#endif /* DEBUG_TRACE */
+
+static void set_sock_priority(int sock) {
+
+	int val;
+
+	/* disable nagle */
+	val = 1;
+	setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (void*)&val, sizeof(val));
+
+	/* set the TOS bit. note that this will fail for ipv6, I can't find any
+	 * equivalent. */
+#ifdef IPTOS_LOWDELAY
+	val = IPTOS_LOWDELAY;
+	setsockopt(sock, IPPROTO_IP, IP_TOS, (void*)&val, sizeof(val));
+#endif
+
+#ifdef SO_PRIORITY
+	/* linux specific, sets QoS class.
+	 * 6 looks to be optimal for interactive traffic (see tc-prio(8) ). */
+	val = 6;
+	setsockopt(sock, SOL_SOCKET, SO_PRIORITY, (void*) &val, sizeof(val));
+#endif
+
+}
+
+/* Listen on address:port. 
+ * Special cases are address of "" listening on everything,
+ * and address of NULL listening on localhost only.
+ * Returns the number of sockets bound on success, or -1 on failure. On
+ * failure, if errstring wasn't NULL, it'll be a newly malloced error
+ * string.*/
+int dropbear_listen(const char* address, const char* port,
+		int *socks, unsigned int sockcount, char **errstring, int *maxfd) {
+
+	struct addrinfo hints, *res = NULL, *res0 = NULL;
+	int err;
+	unsigned int nsock;
+	struct linger linger;
+	int val;
+	int sock;
+
+	TRACE(("enter dropbear_listen"))
+	
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = AF_UNSPEC; /* TODO: let them flag v4 only etc */
+	hints.ai_socktype = SOCK_STREAM;
+
+	// for calling getaddrinfo:
+	// address == NULL and !AI_PASSIVE: local loopback
+	// address == NULL and AI_PASSIVE: all interfaces
+	// address != NULL: whatever the address says
+	if (!address) {
+		TRACE(("dropbear_listen: local loopback"))
+	} else {
+		if (address[0] == '\0') {
+			TRACE(("dropbear_listen: all interfaces"))
+			address = NULL;
+		}
+		hints.ai_flags = AI_PASSIVE;
+	}
+	err = getaddrinfo(address, port, &hints, &res0);
+
+	if (err) {
+		if (errstring != NULL && *errstring == NULL) {
+			int len;
+			len = 20 + strlen(gai_strerror(err));
+			*errstring = (char*)m_malloc(len);
+			snprintf(*errstring, len, "Error resolving: %s", gai_strerror(err));
+		}
+		if (res0) {
+			freeaddrinfo(res0);
+			res0 = NULL;
+		}
+		TRACE(("leave dropbear_listen: failed resolving"))
+		return -1;
+	}
+
+
+	nsock = 0;
+	for (res = res0; res != NULL && nsock < sockcount;
+			res = res->ai_next) {
+
+		/* Get a socket */
+		socks[nsock] = socket(res->ai_family, res->ai_socktype,
+				res->ai_protocol);
+
+		sock = socks[nsock]; /* For clarity */
+
+		if (sock < 0) {
+			err = errno;
+			TRACE(("socket() failed"))
+			continue;
+		}
+
+		/* Various useful socket options */
+		val = 1;
+		/* set to reuse, quick timeout */
+		setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void*) &val, sizeof(val));
+		linger.l_onoff = 1;
+		linger.l_linger = 5;
+		setsockopt(sock, SOL_SOCKET, SO_LINGER, (void*)&linger, sizeof(linger));
+
+		set_sock_priority(sock);
+
+		if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) {
+			err = errno;
+			close(sock);
+			TRACE(("bind(%s) failed", port))
+			continue;
+		}
+
+		if (listen(sock, 20) < 0) {
+			err = errno;
+			close(sock);
+			TRACE(("listen() failed"))
+			continue;
+		}
+
+		*maxfd = MAX(*maxfd, sock);
+
+		nsock++;
+	}
+
+	if (res0) {
+		freeaddrinfo(res0);
+		res0 = NULL;
+	}
+
+	if (nsock == 0) {
+		if (errstring != NULL && *errstring == NULL) {
+			int len;
+			len = 20 + strlen(strerror(err));
+			*errstring = (char*)m_malloc(len);
+			snprintf(*errstring, len, "Error listening: %s", strerror(err));
+			TRACE(("leave dropbear_listen: failure, %s", strerror(err)))
+			return -1;
+		}
+	}
+
+	TRACE(("leave dropbear_listen: success, %d socks bound", nsock))
+	return nsock;
+}
+
+/* Connect via TCP to a host. Connection will try ipv4 or ipv6, will
+ * return immediately if nonblocking is set. On failure, if errstring
+ * wasn't null, it will be a newly malloced error message */
+
+/* TODO: maxfd */
+int connect_remote(const char* remotehost, const char* remoteport,
+		int nonblocking, char ** errstring) {
+
+	struct addrinfo *res0 = NULL, *res = NULL, hints;
+	int sock;
+	int err;
+
+	TRACE(("enter connect_remote"))
+
+	if (errstring != NULL) {
+		*errstring = NULL;
+	}
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_family = PF_UNSPEC;
+
+	err = getaddrinfo(remotehost, remoteport, &hints, &res0);
+	if (err) {
+		if (errstring != NULL && *errstring == NULL) {
+			int len;
+			len = 20 + strlen(gai_strerror(err));
+			*errstring = (char*)m_malloc(len);
+			snprintf(*errstring, len, "Error resolving: %s", gai_strerror(err));
+		}
+		TRACE(("Error resolving: %s", gai_strerror(err)))
+		return -1;
+	}
+
+	sock = -1;
+	err = EADDRNOTAVAIL;
+	for (res = res0; res; res = res->ai_next) {
+
+		sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
+		if (sock < 0) {
+			err = errno;
+			continue;
+		}
+
+		if (nonblocking) {
+			if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) {
+				close(sock);
+				sock = -1;
+				if (errstring != NULL && *errstring == NULL) {
+					*errstring = m_strdup("Failed non-blocking");
+				}
+				TRACE(("Failed non-blocking: %s", strerror(errno)))
+				continue;
+			}
+		}
+
+		if (connect(sock, res->ai_addr, res->ai_addrlen) < 0) {
+			if (errno == EINPROGRESS && nonblocking) {
+				TRACE(("Connect in progress"))
+				break;
+			} else {
+				err = errno;
+				close(sock);
+				sock = -1;
+				continue;
+			}
+		}
+
+		break; /* Success */
+	}
+
+	if (sock < 0 && !(errno == EINPROGRESS && nonblocking)) {
+		/* Failed */
+		if (errstring != NULL && *errstring == NULL) {
+			int len;
+			len = 20 + strlen(strerror(err));
+			*errstring = (char*)m_malloc(len);
+			snprintf(*errstring, len, "Error connecting: %s", strerror(err));
+		}
+		TRACE(("Error connecting: %s", strerror(err)))
+	} else {
+		/* Success */
+		set_sock_priority(sock);
+	}
+
+	freeaddrinfo(res0);
+	if (sock > 0 && errstring != NULL && *errstring != NULL) {
+		m_free(*errstring);
+	}
+
+	TRACE(("leave connect_remote: sock %d\n", sock))
+	return sock;
+}
+
+/* Return a string representation of the socket address passed. The return
+ * value is allocated with malloc() */
+unsigned char * getaddrstring(struct sockaddr_storage* addr, int withport) {
+
+	char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
+	char *retstring = NULL;
+	int ret;
+	unsigned int len;
+
+	len = sizeof(struct sockaddr_storage);
+	/* Some platforms such as Solaris 8 require that len is the length
+	 * of the specific structure. */
+	if (addr->ss_family == AF_INET) {
+		len = sizeof(struct sockaddr_in);
+	}
+#ifdef AF_INET6
+	if (addr->ss_family == AF_INET6) {
+		len = sizeof(struct sockaddr_in6);
+	}
+#endif
+
+	ret = getnameinfo((struct sockaddr*)addr, len, hbuf, sizeof(hbuf), 
+			sbuf, sizeof(sbuf), NI_NUMERICSERV | NI_NUMERICHOST);
+
+	if (ret != 0) {
+		/* This is a fairly bad failure - it'll fallback to IP if it
+		 * just can't resolve */
+		dropbear_exit("failed lookup (%d, %d)", ret, errno);
+	}
+
+	if (withport) {
+		len = strlen(hbuf) + 2 + strlen(sbuf);
+		retstring = (char*)m_malloc(len);
+		snprintf(retstring, len, "%s:%s", hbuf, sbuf);
+	} else {
+		retstring = m_strdup(hbuf);
+	}
+
+	return retstring;
+
+}
+
+/* Get the hostname corresponding to the address addr. On failure, the IP
+ * address is returned. The return value is allocated with strdup() */
+char* getaddrhostname(struct sockaddr_storage * addr) {
+
+	char hbuf[NI_MAXHOST];
+	char sbuf[NI_MAXSERV];
+	int ret;
+	unsigned int len;
+#ifdef DO_HOST_LOOKUP
+	const int flags = NI_NUMERICSERV;
+#else
+	const int flags = NI_NUMERICHOST | NI_NUMERICSERV;
+#endif
+
+	len = sizeof(struct sockaddr_storage);
+	/* Some platforms such as Solaris 8 require that len is the length
+	 * of the specific structure. */
+	if (addr->ss_family == AF_INET) {
+		len = sizeof(struct sockaddr_in);
+	}
+#ifdef AF_INET6
+	if (addr->ss_family == AF_INET6) {
+		len = sizeof(struct sockaddr_in6);
+	}
+#endif
+
+
+	ret = getnameinfo((struct sockaddr*)addr, len, hbuf, sizeof(hbuf),
+			sbuf, sizeof(sbuf), flags);
+
+	if (ret != 0) {
+		/* On some systems (Darwin does it) we get EINTR from getnameinfo
+		 * somehow. Eew. So we'll just return the IP, since that doesn't seem
+		 * to exhibit that behaviour. */
+		return getaddrstring(addr, 0);
+	}
+
+	return m_strdup(hbuf);
+}
+
+#ifdef DEBUG_TRACE
+void printhex(const char * label, const unsigned char * buf, int len) {
+
+	int i;
+
+	fprintf(stderr, "%s\n", label);
+	for (i = 0; i < len; i++) {
+		fprintf(stderr, "%02x", buf[i]);
+		if (i % 16 == 15) {
+			fprintf(stderr, "\n");
+		}
+		else if (i % 2 == 1) {
+			fprintf(stderr, " ");
+		}
+	}
+	fprintf(stderr, "\n");
+}
+#endif
+
+/* Strip all control characters from text (a null-terminated string), except
+ * for '\n', '\r' and '\t'.
+ * The result returned is a newly allocated string, this must be free()d after
+ * use */
+char * stripcontrol(const char * text) {
+
+	char * ret;
+	int len, pos;
+	int i;
+	
+	len = strlen(text);
+	ret = m_malloc(len+1);
+
+	pos = 0;
+	for (i = 0; i < len; i++) {
+		if ((text[i] <= '~' && text[i] >= ' ') /* normal printable range */
+				|| text[i] == '\n' || text[i] == '\r' || text[i] == '\t') {
+			ret[pos] = text[i];
+			pos++;
+		}
+	}
+	ret[pos] = 0x0;
+	return ret;
+}
+			
+
+/* reads the contents of filename into the buffer buf, from the current
+ * position, either to the end of the file, or the buffer being full.
+ * Returns DROPBEAR_SUCCESS or DROPBEAR_FAILURE */
+int buf_readfile(buffer* buf, const char* filename) {
+
+	int fd;
+	int len;
+	int maxlen;
+
+	fd = open(filename, O_RDONLY);
+
+	if (fd < 0) {
+		close(fd);
+		return DROPBEAR_FAILURE;
+	}
+	
+	do {
+		maxlen = buf->size - buf->pos;
+		len = read(fd, buf_getwriteptr(buf, maxlen),
+				maxlen);
+		buf_incrwritepos(buf, len);
+	} while (len < maxlen && len > 0);
+
+	close(fd);
+	return DROPBEAR_SUCCESS;
+}
+
+/* get a line from the file into buffer in the style expected for an
+ * authkeys file.
+ * Will return DROPBEAR_SUCCESS if data is read, or DROPBEAR_FAILURE on EOF.*/
+/* Only used for ~/.ssh/known_hosts and ~/.ssh/authorized_keys */
+#if defined(DROPBEAR_CLIENT) || defined(ENABLE_SVR_PUBKEY_AUTH)
+int buf_getline(buffer * line, FILE * authfile) {
+
+	int c = EOF;
+
+	TRACE(("enter buf_getline"))
+
+	buf_setpos(line, 0);
+	buf_setlen(line, 0);
+
+	while (line->pos < line->size) {
+
+		c = fgetc(authfile); /*getc() is weird with some uClibc systems*/
+		if (c == EOF || c == '\n' || c == '\r') {
+			goto out;
+		}
+
+		buf_putbyte(line, (unsigned char)c);
+	}
+
+	TRACE(("leave getauthline: line too long"))
+	/* We return success, but the line length will be zeroed - ie we just
+	 * ignore that line */
+	buf_setlen(line, 0);
+
+out:
+
+
+	/* if we didn't read anything before EOF or error, exit */
+	if (c == EOF && line->pos == 0) {
+		TRACE(("leave buf_getline: failure"))
+		return DROPBEAR_FAILURE;
+	} else {
+		TRACE(("leave buf_getline: success"))
+		buf_setpos(line, 0);
+		return DROPBEAR_SUCCESS;
+	}
+
+}	
+#endif
+
+/* make sure that the socket closes */
+void m_close(int fd) {
+
+	int val;
+	do {
+		val = close(fd);
+	} while (val < 0 && errno == EINTR);
+
+	if (val < 0 && errno != EBADF) {
+		/* Linux says EIO can happen */
+		dropbear_exit("Error closing fd %d, %s", fd, strerror(errno));
+	}
+}
+	
+void * m_malloc(size_t size) {
+
+	void* ret;
+
+	if (size == 0) {
+		dropbear_exit("m_malloc failed");
+	}
+	ret = calloc(1, size);
+	if (ret == NULL) {
+		dropbear_exit("m_malloc failed");
+	}
+	return ret;
+
+}
+
+void * m_strdup(const char * str) {
+	char* ret;
+
+	ret = strdup(str);
+	if (ret == NULL) {
+		dropbear_exit("m_strdup failed");
+	}
+	return ret;
+}
+
+void __m_free(void* ptr) {
+	if (ptr != NULL) {
+		free(ptr);
+	}
+}
+
+void * m_realloc(void* ptr, size_t size) {
+
+	void *ret;
+
+	if (size == 0) {
+		dropbear_exit("m_realloc failed");
+	}
+	ret = realloc(ptr, size);
+	if (ret == NULL) {
+		dropbear_exit("m_realloc failed");
+	}
+	return ret;
+}
+
+/* Clear the data, based on the method in David Wheeler's
+ * "Secure Programming for Linux and Unix HOWTO" */
+/* Beware of calling this from within dbutil.c - things might get
+ * optimised away */
+void m_burn(void *data, unsigned int len) {
+	volatile char *p = data;
+
+	if (data == NULL)
+		return;
+	while (len--) {
+		*p++ = 0x66;
+	}
+}
+
+
+void setnonblocking(int fd) {
+
+	TRACE(("setnonblocking: %d", fd))
+
+	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) {
+		if (errno == ENODEV) {
+			/* Some devices (like /dev/null redirected in)
+			 * can't be set to non-blocking */
+			TRACE(("ignoring ENODEV for setnonblocking"))
+		} else {
+			dropbear_exit("Couldn't set nonblocking");
+		}
+	}
+	TRACE(("leave setnonblocking"))
+}