- djm@cvs.openbsd.org 2014/07/03 03:47:27

     [ssh-keygen.c]
     When hashing or removing hosts using ssh-keygen, don't choke on
     @revoked markers and don't remove @cert-authority markers;
     bz#2241, reported by mlindgren AT runelind.net

2 files changed, 49 insertions, 26 deletions

diff --git a/ChangeLog b/ChangeLog
index 1b12c37a..0f9f1ed5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -29,6 +29,11 @@
      [gss-serv.c session.c ssh-keygen.c]
      standardise on NI_MAXHOST for gethostname() string lengths; about
      1/2 the cases were using it already. Fixes bz#2239 en passant
+   - djm@cvs.openbsd.org 2014/07/03 03:47:27
+     [ssh-keygen.c]
+     When hashing or removing hosts using ssh-keygen, don't choke on
+     @revoked markers and don't remove @cert-authority markers;
+     bz#2241, reported by mlindgren AT runelind.net
 
 20140702
  - OpenBSD CVS Sync
diff --git a/ssh-keygen.c b/ssh-keygen.c
index 0ec615fd..23058ee9 100644
--- a/ssh-keygen.c
+++ b/ssh-keygen.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-keygen.c,v 1.248 2014/07/03 03:34:09 djm Exp $ */
+/* $OpenBSD: ssh-keygen.c,v 1.249 2014/07/03 03:47:27 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -987,7 +987,7 @@ do_gen_all_hostkeys(struct passwd *pw)
 }
 
 static void
-printhost(FILE *f, const char *name, Key *public, int ca, int hash)
+printhost(FILE *f, const char *name, Key *public, int ca, int revoked, int hash)
 {
 	if (print_fingerprint) {
 		enum fp_rep rep;
@@ -1007,7 +1007,8 @@ printhost(FILE *f, const char *name, Key *public, int ca, int hash)
 	} else {
 		if (hash && (name = host_hash(name, NULL, 0)) == NULL)
 			fatal("hash_host failed");
-		fprintf(f, "%s%s%s ", ca ? CA_MARKER : "", ca ? " " : "", name);
+		fprintf(f, "%s%s%s ", ca ? CA_MARKER " " : "",
+		    revoked ? REVOKE_MARKER " " : "" , name);
 		if (!key_write(public, f))
 			fatal("key_write failed");
 		fprintf(f, "\n");
@@ -1022,7 +1023,7 @@ do_known_hosts(struct passwd *pw, const char *name)
 	char *cp, *cp2, *kp, *kp2;
 	char line[16*1024], tmp[MAXPATHLEN], old[MAXPATHLEN];
 	int c, skip = 0, inplace = 0, num = 0, invalid = 0, has_unhashed = 0;
-	int ca;
+	int ca, revoked;
 	int found_key = 0;
 
 	if (!have_identity) {
@@ -1036,6 +1037,7 @@ do_known_hosts(struct passwd *pw, const char *name)
 	if ((in = fopen(identity_file, "r")) == NULL)
 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
 
+	/* XXX this code is a mess; refactor -djm */
 	/*
 	 * Find hosts goes to stdout, hash and deletions happen in-place
 	 * A corner case is ssh-keygen -HF foo, which should go to stdout
@@ -1079,7 +1081,7 @@ do_known_hosts(struct passwd *pw, const char *name)
 				fprintf(out, "%s\n", cp);
 			continue;
 		}
-		/* Check whether this is a CA key */
+		/* Check whether this is a CA key or revocation marker */
 		if (strncasecmp(cp, CA_MARKER, sizeof(CA_MARKER) - 1) == 0 &&
 		    (cp[sizeof(CA_MARKER) - 1] == ' ' ||
 		    cp[sizeof(CA_MARKER) - 1] == '\t')) {
@@ -1087,6 +1089,14 @@ do_known_hosts(struct passwd *pw, const char *name)
 			cp += sizeof(CA_MARKER);
 		} else
 			ca = 0;
+		if (strncasecmp(cp, REVOKE_MARKER,
+		    sizeof(REVOKE_MARKER) - 1) == 0 &&
+		    (cp[sizeof(REVOKE_MARKER) - 1] == ' ' ||
+		    cp[sizeof(REVOKE_MARKER) - 1] == '\t')) {
+ 			revoked = 1;
+			cp += sizeof(REVOKE_MARKER);
+		} else
+			revoked = 0;
 
 		/* Find the end of the host name portion. */
 		for (kp = cp; *kp && *kp != ' ' && *kp != '\t'; kp++)
@@ -1130,20 +1140,23 @@ do_known_hosts(struct passwd *pw, const char *name)
 						printf("# Host %s found: "
 						    "line %d type %s%s\n", name,
 						    num, key_type(pub),
-						    ca ? " (CA key)" : "");
-					printhost(out, cp, pub, ca, 0);
+						    ca ? " (CA key)" :
+						    revoked? " (revoked)" : "");
+					printhost(out, cp, pub, ca, revoked, 0);
 					found_key = 1;
 				}
 				if (delete_host) {
-					if (!c && !ca)
-						printhost(out, cp, pub, ca, 0);
-					else
+					if (!c || ca || revoked) {
+						printhost(out, cp, pub,
+						    ca, revoked, 0);
+					} else {
 						printf("# Host %s found: "
 						    "line %d type %s\n", name,
 						    num, key_type(pub));
+					}
 				}
 			} else if (hash_hosts)
-				printhost(out, cp, pub, ca, 0);
+				printhost(out, cp, pub, ca, revoked, 0);
 		} else {
 			if (find_host || delete_host) {
 				c = (match_hostname(name, cp,
@@ -1154,38 +1167,43 @@ do_known_hosts(struct passwd *pw, const char *name)
 						    "line %d type %s%s\n", name,
 						    num, key_type(pub),
 						    ca ? " (CA key)" : "");
-					printhost(out, name, pub,
-					    ca, hash_hosts && !ca);
+					printhost(out, name, pub, ca, revoked,
+					    hash_hosts && !(ca || revoked));
 					found_key = 1;
 				}
 				if (delete_host) {
-					if (!c && !ca)
-						printhost(out, cp, pub, ca, 0);
-					else
+					if (!c || ca || revoked) {
+						printhost(out, cp, pub,
+						    ca, revoked, 0);
+					} else {
 						printf("# Host %s found: "
 						    "line %d type %s\n", name,
 						    num, key_type(pub));
+					}
 				}
+			} else if (hash_hosts && (ca || revoked)) {
+				/* Don't hash CA and revoked keys' hostnames */
+				printhost(out, cp, pub, ca, revoked, 0);
+				has_unhashed = 1;
 			} else if (hash_hosts) {
+				/* Hash each hostname separately */
 				for (cp2 = strsep(&cp, ",");
 				    cp2 != NULL && *cp2 != '\0';
 				    cp2 = strsep(&cp, ",")) {
-					if (ca) {
-						fprintf(stderr, "Warning: "
-						    "ignoring CA key for host: "
-						    "%.64s\n", cp2);
-						printhost(out, cp2, pub, ca, 0);
-					} else if (strcspn(cp2, "*?!") !=
+					if (strcspn(cp2, "*?!") !=
 					    strlen(cp2)) {
 						fprintf(stderr, "Warning: "
 						    "ignoring host name with "
 						    "metacharacters: %.64s\n",
 						    cp2);
-						printhost(out, cp2, pub, ca, 0);
-					} else
-						printhost(out, cp2, pub, ca, 1);
+						printhost(out, cp2, pub, ca,
+						    revoked, 0);
+						has_unhashed = 1;
+					} else {
+						printhost(out, cp2, pub, ca,
+						    revoked, 1);
+					}
 				}
-				has_unhashed = 1;
 			}
 		}
 		key_free(pub);