- dtucker@cvs.openbsd.org 2006/03/13 08:43:16

     [ssh-keygen.c]
     Make ssh-keygen handle CR and CRLF line termination when converting IETF
     format keys, in adition to vanilla LF.  mindrot #1157, tested by Chris
     Pepper, ok djm@

1 files changed, 33 insertions, 9 deletions

diff --git a/ssh-keygen.c b/ssh-keygen.c
index 8acbf7783..bea4ed59b 100644
--- a/ssh-keygen.c
+++ b/ssh-keygen.c
@@ -12,7 +12,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh-keygen.c,v 1.136 2006/02/20 17:19:54 stevesk Exp $");
+RCSID("$OpenBSD: ssh-keygen.c,v 1.137 2006/03/13 08:43:16 dtucker Exp $");
 
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -305,13 +305,42 @@ do_convert_private_ssh2_from_blob(u_char *blob, u_int blen)
         return key;
 }
 
+static int
+get_line(FILE *fp, char *line, size_t len)
+{
+        int c;
+        size_t pos = 0;
+
+        line[0] = '\0';
+        while ((c = fgetc(fp)) != EOF) {
+                if (pos >= len - 1) {
+                        fprintf(stderr, "input line too long.\n");
+                        exit(1);
+                }
+                switch(c) {
+                case '\r':
+                        c = fgetc(fp);
+                        if (c != EOF && c != '\n' && ungetc(c, fp) == EOF) {
+                                fprintf(stderr, "unget: %s\n", strerror(errno));
+                                exit(1);
+                        }
+                        return pos;
+                case '\n':
+                        return pos;
+                }
+                line[pos++] = c;
+                line[pos] = '\0';
+        }
+        return pos;
+}
+
 static void
 do_convert_from_ssh2(struct passwd *pw)
 {
         Key *k;
         int blen;
         u_int len;
-        char line[1024], *p;
+        char line[1024];
         u_char blob[8096];
         char encoded[8096];
         struct stat st;
@@ -330,12 +359,8 @@ do_convert_from_ssh2(struct passwd *pw)
                 exit(1);
         }
         encoded[0] = '\0';
-        while (fgets(line, sizeof(line), fp)) {
-                if (!(p = strchr(line, '\n'))) {
-                        fprintf(stderr, "input line too long.\n");
-                        exit(1);
-                }
-                if (p > line && p[-1] == '\\')
+        while ((blen = get_line(fp, line, sizeof(line))) != -1) {
+                if (line[blen - 1] == '\\')
                         escaped++;
                 if (strncmp(line, "----", 4) == 0 ||
                     strstr(line, ": ") != NULL) {
@@ -352,7 +377,6 @@ do_convert_from_ssh2(struct passwd *pw)
                         /* fprintf(stderr, "escaped: %s", line); */
                         continue;
                 }
-                *p = '\0';
                 strlcat(encoded, line, sizeof(encoded));
         }
         len = strlen(encoded);