- Improved the get_secret()'s function comments, made it accept a line

  that doesn't end with a newline, and optimized it a bit.
- Improved getpassf() to work if the line does not end with a newline.

diff --git a/authenticate.c b/authenticate.c
index d1ffca6..927b2bf 100644 (file)
--- a/authenticate.c
+++ b/authenticate.c
@@ -20,6 +20,9 @@
 /* support rsync authentication */
 #include "rsync.h"
 
+extern char *password_file;
+extern int am_root;
+
 /***************************************************************************
 encode a buffer using base64 - simple and slow algorithm. null terminates
 the result.
@@ -68,22 +71,20 @@ static void gen_challenge(char *addr, char *challenge)
 }
 
 
-/* return the secret for a user from the sercret file. maximum length
-   is len. null terminate it */
+/* Return the secret for a user from the secret file, null terminated.
+ * Maximum length is len (not counting the null). */
 static int get_secret(int module, char *user, char *secret, int len)
 {
        char *fname = lp_secrets_file(module);
-       int fd, found=0;
-       char line[MAXPATHLEN];
-       char *p, *pass=NULL;
        STRUCT_STAT st;
-       int ok = 1;
-       extern int am_root;
+       int fd, ok = 1;
+       char ch, *p;
 
-       if (!fname || !*fname) return 0;
+       if (!fname || !*fname)
+               return 0;
 
-       fd = open(fname,O_RDONLY);
-       if (fd == -1) return 0;
+       if ((fd = open(fname, O_RDONLY)) < 0)
+               return 0;
 
        if (do_stat(fname, &st) == -1) {
                rsyserr(FERROR, errno, "stat(%s)", fname);
@@ -103,50 +104,61 @@ static int get_secret(int module, char *user, char *secret, int len)
                return 0;
        }
 
-       while (!found) {
-               int i = 0;
-               memset(line, 0, sizeof line);
-               while ((size_t) i < (sizeof(line)-1)) {
-                       if (read(fd, &line[i], 1) != 1) {
-                               memset(line, 0, sizeof(line));
-                               close(fd);
-                               return 0;
-                       }
-                       if (line[i] == '\r') continue;
-                       if (line[i] == '\n') break;
-                       i++;
+       if (*user == '#') {
+               /* Reject attempt to match a comment. */
+               close(fd);
+               return 0;
+       }
+
+       /* Try to find a line that starts with the user name and a ':'. */
+       p = user;
+       while (1) {
+               if (read(fd, &ch, 1) != 1) {
+                       close(fd);
+                       return 0;
+               }
+               if (ch == '\n')
+                       p = user;
+               else if (p) {
+                       if (*p == ch)
+                               p++;
+                       else if (!*p && ch == ':')
+                               break;
+                       else
+                               p = NULL;
                }
-               line[i] = 0;
-               if (line[0] == '#') continue;
-               p = strchr(line,':');
-               if (!p) continue;
-               *p = 0;
-               if (strcmp(user, line)) continue;
-               pass = p+1;
-               found = 1;
        }
 
+       /* Slurp the secret into the "secret" buffer. */
+       p = secret;
+       while (len > 0) {
+               if (read(fd, p, 1) != 1 || *p == '\n')
+                       break;
+               if (*p == '\r')
+                       continue;
+               p++;
+               len--;
+       }
+       *p = '\0';
        close(fd);
-       if (!found) return 0;
 
-       strlcpy(secret, pass, len);
        return 1;
 }
 
 static char *getpassf(char *filename)
 {
-       char buffer[100];
-       int fd=0;
        STRUCT_STAT st;
-       int ok = 1;
-       extern int am_root;
-       char *envpw=getenv("RSYNC_PASSWORD");
+       char buffer[512], *p;
+       int fd, n, ok = 1;
+       char *envpw = getenv("RSYNC_PASSWORD");
 
-       if (!filename) return NULL;
+       if (!filename)
+               return NULL;
 
-       if ( (fd=open(filename,O_RDONLY)) == -1) {
+       if ((fd = open(filename,O_RDONLY)) < 0) {
                rsyserr(FERROR, errno, "could not open password file \"%s\"",filename);
-               if (envpw) rprintf(FERROR,"falling back to RSYNC_PASSWORD environment variable.\n");    
+               if (envpw)
+                       rprintf(FERROR, "falling back to RSYNC_PASSWORD environment variable.\n");      
                return NULL;
        }
        
@@ -156,26 +168,27 @@ static char *getpassf(char *filename)
        } else if ((st.st_mode & 06) != 0) {
                rprintf(FERROR,"password file must not be other-accessible\n");
                ok = 0;
-       } else if (am_root && (st.st_uid != 0)) {
+       } else if (am_root && st.st_uid != 0) {
                rprintf(FERROR,"password file must be owned by root when running as root\n");
                ok = 0;
        }
        if (!ok) {
                rprintf(FERROR,"continuing without password file\n");
-               if (envpw) rprintf(FERROR,"using RSYNC_PASSWORD environment variable.\n");
+               if (envpw)
+                       rprintf(FERROR, "using RSYNC_PASSWORD environment variable.\n");
                close(fd);
                return NULL;
        }
 
-       if (envpw) rprintf(FERROR,"RSYNC_PASSWORD environment variable ignored\n");
+       if (envpw)
+               rprintf(FERROR, "RSYNC_PASSWORD environment variable ignored\n");
 
-       buffer[sizeof(buffer)-1]='\0';
-       if (read(fd,buffer,sizeof(buffer)-1) > 0)
-       {
-               char *p = strtok(buffer,"\n\r");
-               close(fd);
-               if (p) p = strdup(p);
-               return p;
+       n = read(fd, buffer, sizeof buffer - 1);
+       close(fd);
+       if (n > 0) {
+               buffer[n] = '\0';
+               if ((p = strtok(buffer, "\n\r")) != NULL)
+                       return strdup(p);
        }       
 
        return NULL;
@@ -267,7 +280,6 @@ void auth_client(int fd, char *user, char *challenge)
 {
        char *pass;
        char pass2[30];
-       extern char *password_file;
 
        if (!user || !*user)
                user = "nobody";
@@ -285,9 +297,8 @@ void auth_client(int fd, char *user, char *challenge)
                pass = getpass("Password: ");
        }
 
-       if (!pass || !*pass) {
+       if (!pass)
                pass = "";
-       }
 
        generate_hash(pass, challenge, pass2);
        io_printf(fd, "%s %s\n", user, pass2);