1 files changed, 78 insertions, 58 deletions

diff --git a/gss-genr.c b/gss-genr.c
index 491e62cee..763a63ffa 100644
--- a/gss-genr.c
+++ b/gss-genr.c
@@ -39,12 +39,13 @@
 #include "xmalloc.h"
 #include "ssherr.h"
 #include "sshbuf.h"
-#include "sshkey.h"
 #include "log.h"
 #include "ssh2.h"
 #include "cipher.h"
+#include "sshkey.h"
 #include "kex.h"
 #include "digest.h"
+#include "packet.h"
 
 #include "ssh-gss.h"
 
@@ -65,7 +66,7 @@ Gssctxt *gss_kex_context = NULL;
 
 static ssh_gss_kex_mapping *gss_enc2oid = NULL;
 
-int 
+int
 ssh_gssapi_oid_table_ok(void) {
         return (gss_enc2oid != NULL);
 }
@@ -85,6 +86,21 @@ ssh_gssapi_get_buffer_desc(struct sshbuf *b, gss_buffer_desc *g)
         return 0;
 }
 
+/* sshpkt_get of gss_buffer_desc */
+int
+ssh_gssapi_sshpkt_get_buffer_desc(struct ssh *ssh, gss_buffer_desc *g)
+{
+        int r;
+        u_char *p;
+        size_t len;
+
+        if ((r = sshpkt_get_string(ssh, &p, &len)) != 0)
+                return r;
+        g->value = p;
+        g->length = len;
+        return 0;
+}
+
 /*
  * Return a list of the gss-group1-sha1 mechanisms supported by this program
  *
@@ -93,27 +109,30 @@ ssh_gssapi_get_buffer_desc(struct sshbuf *b, gss_buffer_desc *g)
  */
 
 char *
-ssh_gssapi_client_mechanisms(const char *host, const char *client) {
-        gss_OID_set gss_supported;
+ssh_gssapi_client_mechanisms(const char *host, const char *client,
+    const char *kex) {
+        gss_OID_set gss_supported = NULL;
         OM_uint32 min_status;
 
         if (GSS_ERROR(gss_indicate_mechs(&min_status, &gss_supported)))
                 return NULL;
 
-        return(ssh_gssapi_kex_mechs(gss_supported, ssh_gssapi_check_mechanism,
-            host, client));
+        return ssh_gssapi_kex_mechs(gss_supported, ssh_gssapi_check_mechanism,
+            host, client, kex);
 }
 
 char *
 ssh_gssapi_kex_mechs(gss_OID_set gss_supported, ssh_gssapi_check_fn *check,
-    const char *host, const char *client) {
-        struct sshbuf *buf;
+    const char *host, const char *client, const char *kex) {
+        struct sshbuf *buf = NULL;
         size_t i;
-        int r, oidpos, enclen;
+        int r = SSH_ERR_ALLOC_FAIL;
+        int oidpos, enclen;
         char *mechs, *encoded;
         u_char digest[SSH_DIGEST_MAX_LENGTH];
         char deroid[2];
-        struct ssh_digest_ctx *md;
+        struct ssh_digest_ctx *md = NULL;
+        char *s, *cp, *p;
 
         if (gss_enc2oid != NULL) {
                 for (i = 0; gss_enc2oid[i].encoded != NULL; i++)
@@ -128,6 +147,7 @@ ssh_gssapi_kex_mechs(gss_OID_set gss_supported, ssh_gssapi_check_fn *check,
                 fatal("%s: sshbuf_new failed", __func__);
 
         oidpos = 0;
+        s = cp = xstrdup(kex);
         for (i = 0; i < gss_supported->count; i++) {
                 if (gss_supported->elements[i].length < 128 &&
                     (*check)(NULL, &(gss_supported->elements[i]), host, client)) {
@@ -136,12 +156,15 @@ ssh_gssapi_kex_mechs(gss_OID_set gss_supported, ssh_gssapi_check_fn *check,
                         deroid[1] = gss_supported->elements[i].length;
 
                         if ((md = ssh_digest_start(SSH_DIGEST_MD5)) == NULL ||
-                            ssh_digest_update(md, deroid, 2) != 0 ||
-                            ssh_digest_update(md,
-                            gss_supported->elements[i].elements,
-                            gss_supported->elements[i].length) != 0 ||
-                            ssh_digest_final(md, digest, sizeof(digest)) != 0)
-                                fatal("%s: digest failed", __func__);
+                            (r = ssh_digest_update(md, deroid, 2)) != 0 ||
+                            (r = ssh_digest_update(md,
+                                gss_supported->elements[i].elements,
+                                gss_supported->elements[i].length)) != 0 ||
+                            (r = ssh_digest_final(md, digest, sizeof(digest))) != 0)
+                                fatal("%s: digest failed: %s", __func__,
+                                    ssh_err(r));
+                        ssh_digest_free(md);
+                        md = NULL;
 
                         encoded = xmalloc(ssh_digest_bytes(SSH_DIGEST_MD5)
                             * 2);
@@ -149,69 +172,66 @@ ssh_gssapi_kex_mechs(gss_OID_set gss_supported, ssh_gssapi_check_fn *check,
                             ssh_digest_bytes(SSH_DIGEST_MD5), encoded,
                             ssh_digest_bytes(SSH_DIGEST_MD5) * 2);
 
-                        if (oidpos != 0) {
-                                if ((r = sshbuf_put_u8(buf, ',')) != 0)
-                                        fatal("%s: buffer error: %s",
+                        cp = strncpy(s, kex, strlen(kex));
+                        for ((p = strsep(&cp, ",")); p && *p != '\0';
+                                (p = strsep(&cp, ","))) {
+                                if (sshbuf_len(buf) != 0 &&
+                                    (r = sshbuf_put_u8(buf, ',')) != 0)
+                                        fatal("%s: sshbuf_put_u8 error: %s",
+                                            __func__, ssh_err(r));
+                                if ((r = sshbuf_put(buf, p, strlen(p))) != 0 ||
+                                    (r = sshbuf_put(buf, encoded, enclen)) != 0)
+                                        fatal("%s: sshbuf_put error: %s",
                                             __func__, ssh_err(r));
                         }
 
-                        if ((r = sshbuf_put(buf, KEX_GSS_GEX_SHA1_ID,
-                            sizeof(KEX_GSS_GEX_SHA1_ID) - 1)) != 0 ||
-                            (r = sshbuf_put(buf, encoded, enclen)) != 0 ||
-                            (r = sshbuf_put_u8(buf, ',')) != 0 ||
-                            (r = sshbuf_put(buf, KEX_GSS_GRP1_SHA1_ID,
-                            sizeof(KEX_GSS_GRP1_SHA1_ID) - 1)) != 0 ||
-                            (r = sshbuf_put(buf, encoded, enclen)) != 0 ||
-                            (r = sshbuf_put_u8(buf, ',')) != 0 ||
-                            (r = sshbuf_put(buf, KEX_GSS_GRP14_SHA1_ID,
-                            sizeof(KEX_GSS_GRP14_SHA1_ID) - 1)) != 0 ||
-                            (r = sshbuf_put(buf, encoded, enclen)) != 0)
-                                fatal("%s: buffer error: %s",
-                                    __func__, ssh_err(r));
-
                         gss_enc2oid[oidpos].oid = &(gss_supported->elements[i]);
                         gss_enc2oid[oidpos].encoded = encoded;
                         oidpos++;
                 }
         }
+        free(s);
         gss_enc2oid[oidpos].oid = NULL;
         gss_enc2oid[oidpos].encoded = NULL;
 
         if ((mechs = sshbuf_dup_string(buf)) == NULL)
                 fatal("%s: sshbuf_dup_string failed", __func__);
 
+        sshbuf_free(buf);
+
         if (strlen(mechs) == 0) {
                 free(mechs);
                 mechs = NULL;
         }
-        
+
         return (mechs);
 }
 
 gss_OID
 ssh_gssapi_id_kex(Gssctxt *ctx, char *name, int kex_type) {
         int i = 0;
-        
-        switch (kex_type) {
-        case KEX_GSS_GRP1_SHA1:
-                if (strlen(name) < sizeof(KEX_GSS_GRP1_SHA1_ID))
-                        return GSS_C_NO_OID;
-                name += sizeof(KEX_GSS_GRP1_SHA1_ID) - 1;
-                break;
-        case KEX_GSS_GRP14_SHA1:
-                if (strlen(name) < sizeof(KEX_GSS_GRP14_SHA1_ID))
-                        return GSS_C_NO_OID;
-                name += sizeof(KEX_GSS_GRP14_SHA1_ID) - 1;
-                break;
-        case KEX_GSS_GEX_SHA1:
-                if (strlen(name) < sizeof(KEX_GSS_GEX_SHA1_ID))
-                        return GSS_C_NO_OID;
-                name += sizeof(KEX_GSS_GEX_SHA1_ID) - 1;
+
+#define SKIP_KEX_NAME(type) \
+        case type: \
+                if (strlen(name) < sizeof(type##_ID)) \
+                        return GSS_C_NO_OID; \
+                name += sizeof(type##_ID) - 1; \
                 break;
+
+        switch (kex_type) {
+        SKIP_KEX_NAME(KEX_GSS_GRP1_SHA1)
+        SKIP_KEX_NAME(KEX_GSS_GRP14_SHA1)
+        SKIP_KEX_NAME(KEX_GSS_GRP14_SHA256)
+        SKIP_KEX_NAME(KEX_GSS_GRP16_SHA512)
+        SKIP_KEX_NAME(KEX_GSS_GEX_SHA1)
+        SKIP_KEX_NAME(KEX_GSS_NISTP256_SHA256)
+        SKIP_KEX_NAME(KEX_GSS_C25519_SHA256)
         default:
                 return GSS_C_NO_OID;
         }
 
+#undef SKIP_KEX_NAME
+
         while (gss_enc2oid[i].encoded != NULL &&
             strcmp(name, gss_enc2oid[i].encoded) != 0)
                 i++;
@@ -425,8 +445,8 @@ ssh_gssapi_client_identity(Gssctxt *ctx, const char *name)
             GSS_C_NT_USER_NAME, &gssname);
 
         if (!ctx->major)
-                ctx->major = gss_acquire_cred(&ctx->minor, 
-                    gssname, 0, oidset, GSS_C_INITIATE, 
+                ctx->major = gss_acquire_cred(&ctx->minor,
+                    gssname, 0, oidset, GSS_C_INITIATE,
                     &ctx->client_creds, NULL, NULL);
 
         gss_release_name(&status, &gssname);
@@ -441,7 +461,7 @@ ssh_gssapi_client_identity(Gssctxt *ctx, const char *name)
 OM_uint32
 ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
 {
-        if (ctx == NULL) 
+        if (ctx == NULL)
                 return -1;
 
         if ((ctx->major = gss_get_mic(&ctx->minor, ctx->context,
@@ -480,7 +500,7 @@ ssh_gssapi_buildmic(struct sshbuf *b, const char *user, const char *service,
 }
 
 int
-ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host, 
+ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host,
     const char *client)
 {
         gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
@@ -512,7 +532,7 @@ ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host,
                             GSS_C_NO_BUFFER);
         }
 
-        if (GSS_ERROR(major) || intctx != NULL) 
+        if (GSS_ERROR(major) || intctx != NULL)
                 ssh_gssapi_delete_ctx(ctx);
 
         return (!GSS_ERROR(major));
@@ -527,7 +547,7 @@ ssh_gssapi_credentials_updated(Gssctxt *ctxt) {
         static OM_uint32 last_call = 0;
         OM_uint32 lifetime, now, major, minor;
         int equal;
-        
+
         now = time(NULL);
 
         if (ctxt) {
@@ -555,8 +575,8 @@ ssh_gssapi_credentials_updated(Gssctxt *ctxt) {
 
         if (saved_mech == GSS_C_NO_OID)
                 return 0;
-        
-        major = gss_inquire_cred(&minor, GSS_C_NO_CREDENTIAL, 
+
+        major = gss_inquire_cred(&minor, GSS_C_NO_CREDENTIAL,
             &name, &lifetime, NULL, NULL);
         if (major == GSS_S_CREDENTIALS_EXPIRED)
                 return 0;