From: Todd C. Miller <Todd.Miller@courtesan.com>
Date: Sat, 4 Sep 1993 12:17:33 +0000 (+0000)
Subject: now works correctly (ttaltotal rewrite)
X-Git-Tag: SUDO_1_3_0~109
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=223b37b147823f0aecc17c4981d8717fd4d65cbb;p=sudo

now works correctly (ttaltotal rewrite)
---

diff --git a/qualify.c b/qualify.c
index 399a04f04..e62963e24 100644
--- a/qualify.c
+++ b/qualify.c
@@ -1,51 +1,198 @@
 #include <stdio.h>
 #include <strings.h>
 #include <sys/param.h>
+#include <sys/stat.h>
+#include "sudo.h"
 
-char * mfq (p)
-    char * p;			/* path to make fully qualified */
+/*
+ * qualify() takes a path and makes it fully qualified and resolves
+ * all symbolic links, returning the fully qualfied path.
+ */
+
+char * qualify(n)
+    char * n;				/* name to make fully qualified */
 {
-    char * tmp1, * tmp2;
-    static char path[MAXPATHLEN+1];
-    int done = 0;
+    char * beg = NULL;			/* begining of a path component */
+    char * end;				/* end of a path component */
+    char * tmp;				/* temporary pointer */
+    char name[MAXPATHLEN+1];		/* local copy of n */
+    char full[MAXPATHLEN+1];		/* the fully qualified name */
+    struct stat statbuf;		/* for lstat() */
+    /* for lint and gcc -Wall */
+#ifdef USE_CWD
+    char * getcwd();
+#else
+    char * getwd();
+#endif
+    int fprintf();
+    int readlink();
+    int stat();
+    int lstat();
+    char * strdup();
 
-    if ( *p == '/' )		/* starts at root */
+    if (stat(n, &statbuf))		/* is it a bogus path? */
+	return(NULL);
+
+    /* if n is relative, fill full with working dir */
+    if (*n != '/')
     {
-	path[0] = '\0';
-	++p;
-    }
-    else
-#ifdef hpux
-	getcwd(path, (size_t)(MAXPATHLEN+1));
+#ifdef USE_CWD
+	if (!getcwd(full, (size_t)(MAXPATHLEN+1)))
 #else
-	getwd(path);
+	if (!getwd(full))
 #endif
+	{
+	    fprintf(stderr, "Can't get working dir!  Quitting\n");
+	    exit(-1);
+	}
+    }
+    else
+	full[0] = '\0';
 
-    while ((tmp1 = index(p, '/')) || !done)
+    strcpy(name, n);			/* working copy... */
+
+    do					/* while (end) */
     {
-	if (tmp1)
-    	    *tmp1 = '\0';		/* only want up to '/' */
+	if (beg)
+	    beg = end + 1;		/* skip past the NULL */
 	else
-	    done = 1;
+	    beg = name;			/* just starting out... */
+
+	/* find and terminate end of path component */
+	if ((end = index(beg, '/')))
+	    *end = '\0';
 
-	if (!strcmp(p, ".."))
+	if (beg == end)
+	    continue;
+	else if (!strcmp(beg, "."))
+	    ;				/* ignore "." */
+	else if (!strcmp(beg, ".."))
 	{
-	    tmp2 = rindex(path, '/');
-	    if (tmp2)
-		*tmp2 = '\0';	/* nuke last component if it exists */
+	    tmp = rindex(full, '/');
+	    if (tmp && tmp != &full[0])
+		*tmp = '\0';
 	}
-	else if (strcmp(p, "."))	/* not .. or . */
+	else
 	{
-	    strcat(path, "/");		/* add a '/' */
-	    strcat(path, p);		/* add component form p */
+	    strcat(full, "/");
+	    strcat(full, beg);		/* copy in new component */
 	}
 
-	if (tmp1)
+	/* check for symbolic links */
+	lstat(full, &statbuf);
+	if ((statbuf.st_mode & S_IFMT) == S_IFLNK)
 	{
-	    *tmp1 = '/';		/* leave p as we found it */
-	    p = tmp1 + 1;
+	    char newname[MAXPATHLEN+1];
+	    int linklen;
+
+	    linklen = readlink(full, newname, sizeof(newname));
+	    newname[linklen] = '\0';
+	    
+	    /* check to make sure we don't go past MAXPATHLEN */
+	    ++end;
+	    if (end != (char *)1)
+	    {
+		if (linklen + strlen(end) >= MAXPATHLEN)
+		{
+		    fprintf(stderr, "Symbolic link too long!  Quitting\n");
+		    exit(-1);
+		}
+
+		strcat(newname, "/");
+		strcat(newname, end);	/* copy what's left of end */
+	    }
+
+	    if (newname[0] == '/')	/* reset full if necesary */
+		full[0] = '\0';
+	    else
+		if ((tmp = rindex(full, '/')))	/* remove component from full */
+		    *tmp = '\0';
+
+	    strcpy(name, newname);	/* reset name with new path */
+	    beg = NULL;			/* since we have a new name */
 	}
     }
+    while (end);
+
+    return(strdup(full));		/* malloc space for return path */
+}
+
+/******************************************************************
+ *
+ *  strdup()
+ *
+ *  this function returns a pointer a string copied into 
+ *  a malloc()ed buffer
+ */
+
+char * strdup(s1)
+    char *s1;
+{
+    char * s;
+    char * strcpy();
+    char * malloc();
+
+    if ((s = (char *) malloc(strlen(s1) + 1)) == NULL)
+	return (NULL);
+
+    (void)strcpy(s, s1);
+    return(s);
+}
+
+extern char *malloc();
+extern char *getenv();
+
+extern char **Argv;
+char *find_path();
+char *strdup();
+
+
+
+/*******************************************************************
+ *
+ * find_path()
+ *
+ * this function finds the full pathname for a command
+ */
+
+char *find_path(file)
+char *file;
+{
+    register char *n;
+    char *path=NULL;
+    char fn[MAXPATHLEN+1];
+    char *cmd;
+    struct stat statbuf;		/* for stat() */
+
+    if ( strlen ( file ) > MAXPATHLEN ) {
+	fprintf ( stderr, "%s:  path too long:  %s\n", Argv[0], file );
+	exit (1);
+    }
+	
+    /* do we need to search the path? */
+    if ( index(file, '/') )
+	return (qualify(file));
+
+    /* grab PATH out of environment and make a local copy */
+    if ( ( path = getenv("PATH") ) == NULL )
+	return ( NULL ) ;
+
+    if ( ( path=strdup(path) ) == NULL ) {
+	perror ( "find_path:  malloc" );
+	exit (1);
+    }
+
+    while ( n = index ( path, ':' ) ) {
+	*n='\0';
+	strcpy(fn, path);
+	strcat(fn, "/");
+	strcat(fn, file);
 
-    return((char *)path);
+	/* stat the file to make sure it exists and is executable */
+	if (!stat(fn, &statbuf) && (statbuf.st_mode & 0000111))
+	    return (qualify(fn));
+	else
+	    path=n+1;
+    }
+    return(NULL);
 }