Move local file handling out of url_get()

The code is mostly duplicated already, handling local files here just
makes for more complex code.  Split it out to its own function.  This
mechanically prevents redirections to local files.

Positive feedback from Hiltjo Posthuma

1 files changed, 148 insertions, 142 deletions

diff --git a/usr.bin/ftp/fetch.c b/usr.bin/ftp/fetch.c
index 2f67693c436..64c925230e9 100644
--- a/usr.bin/ftp/fetch.c
+++ b/usr.bin/ftp/fetch.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: fetch.c,v 1.185 2019/12/19 00:07:20 jca Exp $	*/
+/*	$OpenBSD: fetch.c,v 1.186 2020/01/15 14:49:38 jca Exp $	*/
 /*	$NetBSD: fetch.c,v 1.14 1997/08/18 10:20:20 lukem Exp $	*/
 
 /*-
@@ -68,6 +68,7 @@ struct tls;
 #include "ftp_var.h"
 #include "cmds.h"
 
+static int	file_get(const char *, const char *);
 static int	url_get(const char *, const char *, const char *, int);
 static int	save_chunked(FILE *, struct tls *, int , char *, size_t);
 static void	aborthttp(int);
@@ -182,6 +183,125 @@ tooslow(int signo)
 }
 
 /*
+ * Copy a local file (used by the OpenBSD installer).
+ * Returns -1 on failure, 0 on success
+ */
+static int
+file_get(const char *path, const char *outfile)
+{
+	struct stat	 st;
+	int		 fd, out, rval = -1, save_errno;
+	volatile sig_t	 oldintr, oldinti;
+	const char	*savefile;
+	char		*buf = NULL, *cp;
+	const size_t	 buflen = 128 * 1024;
+	off_t		 hashbytes;
+	ssize_t		 len, wlen;
+
+	direction = "received";
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1) {
+		warn("Can't open file %s", path);
+		return -1;
+	}
+
+	if (fstat(fd, &st) == -1)
+		filesize = -1;
+	else
+		filesize = st.st_size;
+
+	if (outfile != NULL)
+		savefile = outfile;
+	else {
+		if (path[strlen(path) - 1] == '/')	/* Consider no file */
+			savefile = NULL;		/* after dir invalid. */
+		else
+			savefile = basename(path);
+	}
+
+	if (EMPTYSTRING(savefile)) {
+		warnx("No filename after directory (use -o): %s", path);
+		goto cleanup_copy;
+	}
+
+	/* Open the output file.  */
+	if (!pipeout) {
+		out = open(savefile, O_CREAT | O_WRONLY | O_TRUNC, 0666);
+		if (out == -1) {
+			warn("Can't open %s", savefile);
+			goto cleanup_copy;
+		}
+	} else
+		out = fileno(stdout);
+
+	if ((buf = malloc(buflen)) == NULL)
+		errx(1, "Can't allocate memory for transfer buffer");
+
+	/* Trap signals */
+	oldintr = NULL;
+	oldinti = NULL;
+	if (setjmp(httpabort)) {
+		if (oldintr)
+			(void)signal(SIGINT, oldintr);
+		if (oldinti)
+			(void)signal(SIGINFO, oldinti);
+		goto cleanup_copy;
+	}
+	oldintr = signal(SIGINT, abortfile);
+
+	bytes = 0;
+	hashbytes = mark;
+	progressmeter(-1, path);
+
+	/* Finally, suck down the file. */
+	oldinti = signal(SIGINFO, psummary);
+	while ((len = read(fd, buf, buflen)) > 0) {
+		bytes += len;
+		for (cp = buf; len > 0; len -= wlen, cp += wlen) {
+			if ((wlen = write(out, cp, len)) == -1) {
+				warn("Writing %s", savefile);
+				signal(SIGINFO, oldinti);
+				goto cleanup_copy;
+			}
+		}
+		if (hash && !progress) {
+			while (bytes >= hashbytes) {
+				(void)putc('#', ttyout);
+				hashbytes += mark;
+			}
+			(void)fflush(ttyout);
+		}
+	}
+	save_errno = errno;
+	signal(SIGINFO, oldinti);
+	if (hash && !progress && bytes > 0) {
+		if (bytes < mark)
+			(void)putc('#', ttyout);
+		(void)putc('\n', ttyout);
+		(void)fflush(ttyout);
+	}
+	if (len == -1) {
+		warnc(save_errno, "Reading from file");
+		goto cleanup_copy;
+	}
+	progressmeter(1, NULL);
+	if (verbose)
+		ptransfer(0);
+	(void)signal(SIGINT, oldintr);
+
+	rval = 0;
+
+cleanup_copy:
+	free(buf);
+	if (out >= 0 && out != fileno(stdout))
+		close(out);
+	close(fd);
+
+	return rval;
+}
+
+/*
  * Retrieve URL, via the proxy in $proxyvar if necessary.
  * Returns -1 on failure, 0 on success
  */
@@ -191,7 +311,7 @@ url_get(const char *origline, const char *proxyenv, const char *outfile, int las
 	char pbuf[NI_MAXSERV], hbuf[NI_MAXHOST], *cp, *portnum, *path, ststr[4];
 	char *hosttail, *cause = "unknown", *newline, *host, *port, *buf = NULL;
 	char *epath, *redirurl, *loctail, *h, *p, gerror[200];
-	int error, i, isftpurl = 0, isfileurl = 0, isredirect = 0, rval = -1;
+	int error, i, isftpurl = 0, isredirect = 0, rval = -1;
 	int isunavail = 0, retryafter = -1;
 	struct addrinfo hints, *res0, *res;
 	const char * volatile savefile;
@@ -239,12 +359,6 @@ url_get(const char *origline, const char *proxyenv, const char *outfile, int las
 #ifndef SMALL
 		scheme = FTP_URL;
 #endif /* !SMALL */
-	} else if (strncasecmp(newline, FILE_URL, sizeof(FILE_URL) - 1) == 0) {
-		host = newline + sizeof(FILE_URL) - 1;
-		isfileurl = 1;
-#ifndef SMALL
-		scheme = FILE_URL;
-#endif /* !SMALL */
 	} else if (strncasecmp(newline, HTTPS_URL, sizeof(HTTPS_URL) - 1) == 0) {
 #ifndef NOSSL
 		host = newline + sizeof(HTTPS_URL) - 1;
@@ -256,32 +370,25 @@ url_get(const char *origline, const char *proxyenv, const char *outfile, int las
 		scheme = HTTPS_URL;
 #endif /* !SMALL */
 	} else
-		errx(1, "url_get: Invalid URL '%s'", newline);
+		errx(1, "%s: URL not permitted", newline);
 
-	if (isfileurl && redirect_loop > 0)
-		errx(1, "Redirection to local file not permitted");
-
-	if (isfileurl) {
-		path = host;
-	} else {
-		path = strchr(host, '/');		/* Find path */
-		if (EMPTYSTRING(path)) {
-			if (outfile) {			/* No slash, but */
-				path=strchr(host,'\0');	/* we have outfile. */
-				goto noslash;
-			}
-			if (isftpurl)
-				goto noftpautologin;
-			warnx("No `/' after host (use -o): %s", origline);
-			goto cleanup_url_get;
-		}
-		*path++ = '\0';
-		if (EMPTYSTRING(path) && !outfile) {
-			if (isftpurl)
-				goto noftpautologin;
-			warnx("No filename after host (use -o): %s", origline);
-			goto cleanup_url_get;
+	path = strchr(host, '/');		/* Find path */
+	if (EMPTYSTRING(path)) {
+		if (outfile) {				/* No slash, but */
+			path = strchr(host,'\0');	/* we have outfile. */
+			goto noslash;
 		}
+		if (isftpurl)
+			goto noftpautologin;
+		warnx("No `/' after host (use -o): %s", origline);
+		goto cleanup_url_get;
+	}
+	*path++ = '\0';
+	if (EMPTYSTRING(path) && !outfile) {
+		if (isftpurl)
+			goto noftpautologin;
+		warnx("No filename after host (use -o): %s", origline);
+		goto cleanup_url_get;
 	}
 
 noslash:
@@ -324,7 +431,7 @@ noslash:
 	}
 #endif /* !SMALL */
 
-	if (!isfileurl && proxyenv != NULL) {		/* use proxy */
+	if (proxyenv != NULL) {		/* use proxy */
 #ifndef NOSSL
 		if (ishttpsurl) {
 			sslpath = strdup(path);
@@ -381,112 +488,6 @@ noslash:
 		path = newline;
 	}
 
-	if (isfileurl) {
-		struct stat st;
-
-		fd = open(path, O_RDONLY);
-		if (fd == -1) {
-			warn("Can't open file %s", path);
-			goto cleanup_url_get;
-		}
-
-		if (fstat(fd, &st) == -1)
-			filesize = -1;
-		else
-			filesize = st.st_size;
-
-		/* Open the output file.  */
-		if (!pipeout) {
-#ifndef SMALL
-			if (resume)
-				out = open(savefile, O_CREAT | O_WRONLY |
-					O_APPEND, 0666);
-
-			else
-#endif /* !SMALL */
-				out = open(savefile, O_CREAT | O_WRONLY |
-					O_TRUNC, 0666);
-			if (out < 0) {
-				warn("Can't open %s", savefile);
-				goto cleanup_url_get;
-			}
-		} else
-			out = fileno(stdout);
-
-#ifndef SMALL
-		if (resume) {
-			if (fstat(out, &st) == -1) {
-				warn("Can't fstat %s", savefile);
-				goto cleanup_url_get;
-			}
-			if (lseek(fd, st.st_size, SEEK_SET) == -1) {
-				warn("Can't lseek %s", path);
-				goto cleanup_url_get;
-			}
-			restart_point = st.st_size;
-		}
-#endif /* !SMALL */
-
-		/* Trap signals */
-		oldintr = NULL;
-		oldinti = NULL;
-		if (setjmp(httpabort)) {
-			if (oldintr)
-				(void)signal(SIGINT, oldintr);
-			if (oldinti)
-				(void)signal(SIGINFO, oldinti);
-			goto cleanup_url_get;
-		}
-		oldintr = signal(SIGINT, abortfile);
-
-		bytes = 0;
-		hashbytes = mark;
-		progressmeter(-1, path);
-
-		if ((buf = malloc(buflen)) == NULL)
-			errx(1, "Can't allocate memory for transfer buffer");
-
-		/* Finally, suck down the file. */
-		i = 0;
-		oldinti = signal(SIGINFO, psummary);
-		while ((len = read(fd, buf, buflen)) > 0) {
-			bytes += len;
-			for (cp = buf; len > 0; len -= i, cp += i) {
-				if ((i = write(out, cp, len)) == -1) {
-					warn("Writing %s", savefile);
-					signal(SIGINFO, oldinti);
-					goto cleanup_url_get;
-				} else if (i == 0)
-					break;
-			}
-			if (hash && !progress) {
-				while (bytes >= hashbytes) {
-					(void)putc('#', ttyout);
-					hashbytes += mark;
-				}
-				(void)fflush(ttyout);
-			}
-		}
-		signal(SIGINFO, oldinti);
-		if (hash && !progress && bytes > 0) {
-			if (bytes < mark)
-				(void)putc('#', ttyout);
-			(void)putc('\n', ttyout);
-			(void)fflush(ttyout);
-		}
-		if (len != 0) {
-			warn("Reading from file");
-			goto cleanup_url_get;
-		}
-		progressmeter(1, NULL);
-		if (verbose)
-			ptransfer(0);
-		(void)signal(SIGINT, oldintr);
-
-		rval = 0;
-		goto cleanup_url_get;
-	}
-
 	if (*host == '[' && (hosttail = strrchr(host, ']')) != NULL &&
 	    (hosttail[1] == '\0' || hosttail[1] == ':')) {
 		host++;
@@ -1272,12 +1273,17 @@ auto_fetch(int argc, char *argv[], char *outfile)
 		if (url == NULL)
 			errx(1, "Can't allocate memory for auto-fetch.");
 
+		if (strncasecmp(url, FILE_URL, sizeof(FILE_URL) - 1) == 0) {
+			if (file_get(url + sizeof(FILE_URL) - 1, outfile) == -1)
+				rval = argpos + 1;
+			continue;
+		}
+
 		/*
-		 * Try HTTP URL-style arguments first.
+		 * Try HTTP URL-style arguments next.
 		 */
 		if (strncasecmp(url, HTTP_URL, sizeof(HTTP_URL) - 1) == 0 ||
-		    strncasecmp(url, HTTPS_URL, sizeof(HTTPS_URL) -1) == 0 ||
-		    strncasecmp(url, FILE_URL, sizeof(FILE_URL) - 1) == 0) {
+		    strncasecmp(url, HTTPS_URL, sizeof(HTTPS_URL) -1) == 0) {
 			redirect_loop = 0;
 			retried = 0;
 			if (url_get(url, httpproxy, outfile, lastfile) == -1)