diff --git a/src/common/crypto.c b/src/common/crypto.c
index 218c7bea1e..06631e1604 100644
--- a/src/common/crypto.c
+++ b/src/common/crypto.c
@@ -1724,7 +1724,24 @@ crypto_digest_assign(crypto_digest_t *into,
  * <b>out_len</b> must be \<= DIGEST256_LEN. */
 void
 crypto_digest_smartlist(char *digest_out, size_t len_out,
-                        const smartlist_t *lst, const char *append,
+                        const smartlist_t *lst,
+                        const char *append,
+                        digest_algorithm_t alg)
+{
+  crypto_digest_smartlist_prefix(digest_out, len_out, NULL, lst, append, alg);
+}
+
+/** Given a list of strings in <b>lst</b>, set the <b>len_out</b>-byte digest
+ * at <b>digest_out</b> to the hash of the concatenation of: the
+ * optional string <b>prepend</b>, those strings,
+ * and the optional string <b>append</b>, computed with the algorithm
+ * <b>alg</b>.
+ * <b>out_len</b> must be \<= DIGEST256_LEN. */
+void
+crypto_digest_smartlist_prefix(char *digest_out, size_t len_out,
+                        const char *prepend,
+                        const smartlist_t *lst,
+                        const char *append,
                         digest_algorithm_t alg)
 {
   crypto_digest_t *d;
@@ -1732,6 +1749,8 @@ crypto_digest_smartlist(char *digest_out, size_t len_out,
     d = crypto_digest_new();
   else
     d = crypto_digest256_new(alg);
+  if (prepend)
+    crypto_digest_add_bytes(d, prepend, strlen(prepend));
   SMARTLIST_FOREACH(lst, const char *, cp,
                     crypto_digest_add_bytes(d, cp, strlen(cp)));
   if (append)
@@ -2692,6 +2711,8 @@ base64_encode(char *dest, size_t destlen, const char *src, size_t srclen)
     return -1;
   if (destlen > SIZE_T_CEILING)
     return -1;
+  if (destlen)
+    *dest = 0; /* Ensure we always initialize the buffer */
 
   EVP_EncodeInit(&ctx);
   EVP_EncodeUpdate(&ctx, (unsigned char*)dest, &len,
@@ -2701,6 +2722,65 @@ base64_encode(char *dest, size_t destlen, const char *src, size_t srclen)
   return ret;
 }
 
+/** As base64_encode, but do not add any internal spaces or external padding
+ * to the output stream. */
+int
+base64_encode_nopad(char *dest, size_t destlen,
+                    const uint8_t *src, size_t srclen)
+{
+  int n = base64_encode(dest, destlen, (const char*) src, srclen);
+  if (n <= 0)
+    return n;
+  tor_assert((size_t)n < destlen && dest[n] == 0);
+  char *in, *out;
+  in = out = dest;
+  while (*in) {
+    if (*in == '=' || *in == '\n') {
+      ++in;
+    } else {
+      *out++ = *in++;
+    }
+  }
+  *out = 0;
+
+  tor_assert(out - dest <= INT_MAX);
+
+  return (int)(out - dest);
+}
+
+/** As base64_decode, but do not require any padding on the input */
+int
+base64_decode_nopad(uint8_t *dest, size_t destlen,
+                    const char *src, size_t srclen)
+{
+  if (srclen > SIZE_T_CEILING - 4)
+    return -1;
+  char *buf = tor_malloc(srclen + 4);
+  memcpy(buf, src, srclen+1);
+  size_t buflen;
+  switch (srclen % 4)
+    {
+    case 0:
+    default:
+      buflen = srclen;
+      break;
+    case 1:
+      tor_free(buf);
+      return -1;
+    case 2:
+      memcpy(buf+srclen, "==", 3);
+      buflen = srclen + 2;
+      break;
+    case 3:
+      memcpy(buf+srclen, "=", 2);
+      buflen = srclen + 1;
+      break;
+  }
+  int n = base64_decode((char*)dest, destlen, buf, buflen);
+  tor_free(buf);
+  return n;
+}
+
 /** @{ */
 /** Special values used for the base64_decode_table */
 #define X 255
diff --git a/src/common/crypto.h b/src/common/crypto.h
index d305bc17a0..526619766d 100644
--- a/src/common/crypto.h
+++ b/src/common/crypto.h
@@ -207,6 +207,11 @@ int crypto_digest256(char *digest, const char *m, size_t len,
                      digest_algorithm_t algorithm);
 int crypto_digest_all(digests_t *ds_out, const char *m, size_t len);
 struct smartlist_t;
+void crypto_digest_smartlist_prefix(char *digest_out, size_t len_out,
+                                    const char *prepend,
+                                    const struct smartlist_t *lst,
+                                    const char *append,
+                                    digest_algorithm_t alg);
 void crypto_digest_smartlist(char *digest_out, size_t len_out,
                              const struct smartlist_t *lst, const char *append,
                              digest_algorithm_t alg);
@@ -270,6 +275,11 @@ void smartlist_shuffle(struct smartlist_t *sl);
 
 int base64_encode(char *dest, size_t destlen, const char *src, size_t srclen);
 int base64_decode(char *dest, size_t destlen, const char *src, size_t srclen);
+int base64_encode_nopad(char *dest, size_t destlen,
+                        const uint8_t *src, size_t srclen);
+int base64_decode_nopad(uint8_t *dest, size_t destlen,
+                        const char *src, size_t srclen);
+
 /** Characters that can appear (case-insensitively) in a base32 encoding. */
 #define BASE32_CHARS "abcdefghijklmnopqrstuvwxyz234567"
 void base32_encode(char *dest, size_t destlen, const char *src, size_t srclen);
diff --git a/src/common/crypto_ed25519.c b/src/common/crypto_ed25519.c
index 7e8b00abef..6b93751dda 100644
--- a/src/common/crypto_ed25519.c
+++ b/src/common/crypto_ed25519.c
@@ -351,6 +351,7 @@ ed25519_pubkey_read_from_file(ed25519_public_key_t *pubkey_out,
   return 0;
 }
 
+/** Release all storage held for <b>kp</b>. */
 void
 ed25519_keypair_free(ed25519_keypair_t *kp)
 {
@@ -361,3 +362,13 @@ ed25519_keypair_free(ed25519_keypair_t *kp)
   tor_free(kp);
 }
 
+/** Return true iff <b>key1</b> and <b>key2</b> are the same public key. */
+int
+ed25519_pubkey_eq(const ed25519_public_key_t *key1,
+                  const ed25519_public_key_t *key2)
+{
+  tor_assert(key1);
+  tor_assert(key2);
+  return tor_memeq(key1->pubkey, key2->pubkey, ED25519_PUBKEY_LEN);
+}
+
diff --git a/src/common/crypto_ed25519.h b/src/common/crypto_ed25519.h
index 8e06191fc5..79b3db8f9a 100644
--- a/src/common/crypto_ed25519.h
+++ b/src/common/crypto_ed25519.h
@@ -95,6 +95,13 @@ int ed25519_public_from_base64(ed25519_public_key_t *pkey,
 int ed25519_public_to_base64(char *output,
                              const ed25519_public_key_t *pkey);
 
+#define ED25519_SIG_BASE64_LEN 86
+
+int ed25519_signature_from_base64(ed25519_signature_t *sig,
+                                  const char *input);
+int ed25519_signature_to_base64(char *output,
+                                const ed25519_signature_t *sig);
+
 /* XXXX read encrypted, write encrypted. */
 
 int ed25519_seckey_write_to_file(const ed25519_secret_key_t *seckey,
@@ -112,5 +119,8 @@ int ed25519_pubkey_read_from_file(ed25519_public_key_t *pubkey_out,
 
 void ed25519_keypair_free(ed25519_keypair_t *kp);
 
+int ed25519_pubkey_eq(const ed25519_public_key_t *key1,
+                      const ed25519_public_key_t *key2);
+
 #endif
 
diff --git a/src/common/crypto_format.c b/src/common/crypto_format.c
index 00e0e9ea85..503d1de932 100644
--- a/src/common/crypto_format.c
+++ b/src/common/crypto_format.c
@@ -65,3 +65,42 @@ ed25519_public_to_base64(char *output,
   return digest256_to_base64(output, (const char *)pkey->pubkey);
 }
 
+/** Encode the signature <b>sig</b> into the buffer at <b>output</b>,
+ * which must have space for ED25519_SIG_BASE64_LEN bytes of encoded signature,
+ * plus one byte for a terminating NUL.  Return 0 on success, -1 on failure.
+ */
+int
+ed25519_signature_to_base64(char *output,
+                            const ed25519_signature_t *sig)
+{
+  char buf[256];
+  int n = base64_encode_nopad(buf, sizeof(buf), sig->sig, ED25519_SIG_LEN);
+  tor_assert(n == ED25519_SIG_BASE64_LEN);
+  memcpy(output, buf, ED25519_SIG_BASE64_LEN+1);
+  return 0;
+}
+
+/** Try to decode the string <b>input</b> into an ed25519 signature. On
+ * success, store the value in <b>sig</b> and return 0. Otherwise return
+ * -1. */
+int
+ed25519_signature_from_base64(ed25519_signature_t *sig,
+                              const char *input)
+{
+
+  if (strlen(input) != ED25519_SIG_BASE64_LEN)
+    return -1;
+  char buf[ED25519_SIG_BASE64_LEN+3];
+  memcpy(buf, input, ED25519_SIG_BASE64_LEN);
+  buf[ED25519_SIG_BASE64_LEN+0] = '=';
+  buf[ED25519_SIG_BASE64_LEN+1] = '=';
+  buf[ED25519_SIG_BASE64_LEN+2] = 0;
+  char decoded[128];
+  int n = base64_decode(decoded, sizeof(decoded), buf, strlen(buf));
+  if (n < 0 || n != ED25519_SIG_LEN)
+    return -1;
+  memcpy(sig->sig, decoded, ED25519_SIG_LEN);
+
+  return 0;
+}
+
diff --git a/src/or/or.h b/src/or/or.h
index 2044e844c3..437183e727 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -2021,6 +2021,8 @@ typedef struct {
   crypto_pk_t *identity_pkey;  /**< Public RSA key for signing. */
   /** Public curve25519 key for onions */
   curve25519_public_key_t *onion_curve25519_pkey;
+  /** Certificate for ed25519 signing key */
+  struct tor_cert_st *signing_key_cert;
 
   char *platform; /**< What software/operating system is this OR using? */
 
diff --git a/src/or/router.c b/src/or/router.c
index 135561381f..6b2a238140 100644
--- a/src/or/router.c
+++ b/src/or/router.c
@@ -30,6 +30,7 @@
 #include "routerlist.h"
 #include "routerparse.h"
 #include "statefile.h"
+#include "torcert.h"
 #include "transports.h"
 #include "routerset.h"
 
@@ -1881,6 +1882,8 @@ router_rebuild_descriptor(int force)
     routerinfo_free(ri);
     return -1;
   }
+  ri->signing_key_cert = tor_cert_dup(get_master_signing_key_cert());
+
   get_platform_str(platform, sizeof(platform));
   ri->platform = tor_strdup(platform);
 
@@ -1995,8 +1998,9 @@ router_rebuild_descriptor(int force)
     /* ri was allocated with tor_malloc_zero, so there is no need to
      * zero ri->cache_info.extra_info_digest here. */
   }
-  if (! (ri->cache_info.signed_descriptor_body = router_dump_router_to_string(
-                                           ri, get_server_identity_key()))) {
+  if (! (ri->cache_info.signed_descriptor_body =
+          router_dump_router_to_string(ri, get_server_identity_key(),
+                                       get_master_signing_keypair())) ) {
     log_warn(LD_BUG, "Couldn't generate router descriptor.");
     routerinfo_free(ri);
     extrainfo_free(ei);
@@ -2302,12 +2306,13 @@ get_platform_str(char *platform, size_t len)
  */
 char *
 router_dump_router_to_string(routerinfo_t *router,
-                             crypto_pk_t *ident_key)
+                             crypto_pk_t *ident_key,
+                             const ed25519_keypair_t *signing_keypair)
 {
   char *address = NULL;
   char *onion_pkey = NULL; /* Onion key, PEM-encoded. */
   char *identity_pkey = NULL; /* Identity key, PEM-encoded. */
-  char digest[DIGEST_LEN];
+  char digest[DIGEST256_LEN];
   char published[ISO_TIME_LEN+1];
   char fingerprint[FINGERPRINT_LEN+1];
   int has_extra_info_digest;
@@ -2318,6 +2323,8 @@ router_dump_router_to_string(routerinfo_t *router,
   const or_options_t *options = get_options();
   smartlist_t *chunks = NULL;
   char *output = NULL;
+  const int emit_ed_sigs = signing_keypair && router->signing_key_cert;
+  char *ed_cert_line = NULL;
 
   /* Make sure the identity key matches the one in the routerinfo. */
   if (!crypto_pk_eq_keys(ident_key, router->identity_pkey)) {
@@ -2325,6 +2332,15 @@ router_dump_router_to_string(routerinfo_t *router,
              "match router's public key!");
     goto err;
   }
+  if (emit_ed_sigs) {
+    if (!router->signing_key_cert->signing_key_included ||
+        !ed25519_pubkey_eq(&router->signing_key_cert->signed_key,
+                           &signing_keypair->pubkey)) {
+      log_warn(LD_BUG, "Tried to sign a router descriptor with a mismatched "
+               "ed25519 key chain");
+      goto err;
+    }
+  }
 
   /* record our fingerprint, so we can include it in the descriptor */
   if (crypto_pk_get_fingerprint(router->identity_pkey, fingerprint, 1)<0) {
@@ -2332,6 +2348,21 @@ router_dump_router_to_string(routerinfo_t *router,
     goto err;
   }
 
+  if (emit_ed_sigs) {
+    /* Encode ed25519 signing cert */
+    char ed_cert_base64[256];
+    if (base64_encode(ed_cert_base64, sizeof(ed_cert_base64),
+                      (const char*)router->signing_key_cert->encoded,
+                      router->signing_key_cert->encoded_len) < 0) {
+      log_err(LD_BUG,"Couldn't base64-encode signing key certificate!");
+      goto err;
+    }
+    tor_asprintf(&ed_cert_line, "identity-ed25519\n"
+                 "-----BEGIN ED25519 CERT-----\n"
+                 "%s"
+                 "-----END ED25519 CERT-----\n", ed_cert_base64);
+  }
+
   /* PEM-encode the onion key */
   if (crypto_pk_write_public_key_to_string(router->onion_pkey,
                                            &onion_pkey,&onion_pkeylen)<0) {
@@ -2385,6 +2416,7 @@ router_dump_router_to_string(routerinfo_t *router,
   smartlist_add_asprintf(chunks,
                     "router %s %s %d 0 %d\n"
                     "%s"
+                    "%s"
                     "platform %s\n"
                     "protocols Link 1 2 Circuit 1\n"
                     "published %s\n"
@@ -2399,6 +2431,7 @@ router_dump_router_to_string(routerinfo_t *router,
     address,
     router->or_port,
     decide_to_advertise_dirport(options, router->dir_port),
+    ed_cert_line ? ed_cert_line : "",
     extra_or_address ? extra_or_address : "",
     router->platform,
     published,
@@ -2455,7 +2488,24 @@ router_dump_router_to_string(routerinfo_t *router,
     tor_free(p6);
   }
 
-  /* Sign the descriptor */
+  /* Sign the descriptor with Ed25519 */
+  if (emit_ed_sigs)  {
+    smartlist_add(chunks, tor_strdup("router-sig-ed25519 "));
+    crypto_digest_smartlist_prefix(digest, DIGEST256_LEN,
+                                   ED_DESC_SIGNATURE_PREFIX,
+                                   chunks, "", DIGEST_SHA256);
+    ed25519_signature_t sig;
+    char buf[ED25519_SIG_BASE64_LEN+1];
+    if (ed25519_sign(&sig, (const uint8_t*)digest, DIGEST256_LEN,
+                     signing_keypair) < 0)
+      goto err;
+    if (ed25519_signature_to_base64(buf, &sig) < 0)
+      goto err;
+
+    smartlist_add_asprintf(chunks, "%s\n", buf);
+  }
+
+  /* Sign the descriptor with RSA */
   smartlist_add(chunks, tor_strdup("router-signature\n"));
 
   crypto_digest_smartlist(digest, DIGEST_LEN, chunks, "", DIGEST_SHA1);
@@ -2507,6 +2557,7 @@ router_dump_router_to_string(routerinfo_t *router,
   tor_free(onion_pkey);
   tor_free(identity_pkey);
   tor_free(extra_or_address);
+  tor_free(ed_cert_line);
 
   return output;
 }
diff --git a/src/or/router.h b/src/or/router.h
index 8108ffb22f..c53a104ebc 100644
--- a/src/or/router.h
+++ b/src/or/router.h
@@ -91,7 +91,8 @@ int router_is_me(const routerinfo_t *router);
 int router_pick_published_address(const or_options_t *options, uint32_t *addr);
 int router_rebuild_descriptor(int force);
 char *router_dump_router_to_string(routerinfo_t *router,
-                                   crypto_pk_t *ident_key);
+                                   crypto_pk_t *ident_key,
+                                   const ed25519_keypair_t *signing_keypair);
 char *router_dump_exit_policy_to_string(const routerinfo_t *router,
                                          int include_ipv4,
                                          int include_ipv6);
diff --git a/src/or/routerkeys.c b/src/or/routerkeys.c
index fb61c310bd..6609d89311 100644
--- a/src/or/routerkeys.c
+++ b/src/or/routerkeys.c
@@ -300,7 +300,7 @@ load_ed_keys(const or_options_t *options, time_t now)
   (void) options;
 
   id = ed_key_init_from_file(
-               options_get_datadir_fname2(options, "keys", "ed25519_master_id"),
+             options_get_datadir_fname2(options, "keys", "ed25519_master_id"),
                              (INIT_ED_KEY_CREATE|INIT_ED_KEY_SPLIT|
                               INIT_ED_KEY_MISSING_SECRET_OK|
                               INIT_ED_KEY_EXTRA_STRONG),
diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index f4f6200bbc..069f70d662 100644
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -13,6 +13,7 @@
 
 #define ROUTERLIST_PRIVATE
 #include "or.h"
+#include "crypto_ed25519.h"
 #include "circuitstats.h"
 #include "config.h"
 #include "connection.h"
@@ -38,6 +39,7 @@
 #include "routerparse.h"
 #include "routerset.h"
 #include "../common/sandbox.h"
+#include "torcert.h"
 // #define DEBUG_ROUTERLIST
 
 /****************************************************************************/
@@ -2663,6 +2665,7 @@ routerinfo_free(routerinfo_t *router)
   tor_free(router->onion_curve25519_pkey);
   if (router->identity_pkey)
     crypto_pk_free(router->identity_pkey);
+  tor_cert_free(router->signing_key_cert);
   if (router->declared_family) {
     SMARTLIST_FOREACH(router->declared_family, char *, s, tor_free(s));
     smartlist_free(router->declared_family);
diff --git a/src/or/routerparse.c b/src/or/routerparse.c
index 5a9626f0a2..dbd6fdd472 100644
--- a/src/or/routerparse.c
+++ b/src/or/routerparse.c
@@ -26,6 +26,8 @@
 #include "rephist.h"
 #include "routerparse.h"
 #include "entrynodes.h"
+#include "torcert.h"
+
 #undef log
 #include <math.h>
 
@@ -83,6 +85,8 @@ typedef enum {
   K_HIDDEN_SERVICE_DIR,
   K_ALLOW_SINGLE_HOP_EXITS,
   K_IPV6_POLICY,
+  K_ROUTER_SIG_ED25519,
+  K_IDENTITY_ED25519,
 
   K_DIRREQ_END,
   K_DIRREQ_V2_IPS,
@@ -293,6 +297,9 @@ static token_rule_t routerdesc_token_table[] = {
   T01("write-history",       K_WRITE_HISTORY,       ARGS,    NO_OBJ ),
   T01("extra-info-digest",   K_EXTRA_INFO_DIGEST,   GE(1),   NO_OBJ ),
   T01("hidden-service-dir",  K_HIDDEN_SERVICE_DIR,  NO_ARGS, NO_OBJ ),
+  T01("identity-ed25519",    K_IDENTITY_ED25519,    NO_ARGS, NEED_OBJ ),
+  T01("router-sig-ed25519",  K_ROUTER_SIG_ED25519,  GE(1),   NO_OBJ ),
+
   T01("allow-single-hop-exits",K_ALLOW_SINGLE_HOP_EXITS,    NO_ARGS, NO_OBJ ),
 
   T01("family",              K_FAMILY,              ARGS,    NO_OBJ ),
@@ -506,6 +513,10 @@ static addr_policy_t *router_parse_addr_policy(directory_token_t *tok,
                                                unsigned fmt_flags);
 static addr_policy_t *router_parse_addr_policy_private(directory_token_t *tok);
 
+static int router_get_hash_impl_helper(const char *s, size_t s_len,
+                            const char *start_str,
+                            const char *end_str, char end_c,
+                            const char **start_out, const char **end_out);
 static int router_get_hash_impl(const char *s, size_t s_len, char *digest,
                                 const char *start_str, const char *end_str,
                                 char end_char,
@@ -1302,6 +1313,86 @@ router_parse_entry_from_string(const char *s, const char *end,
       tor_memdup(&k, sizeof(curve25519_public_key_t));
   }
 
+  {
+    directory_token_t *ed_sig_tok, *ed_cert_tok;
+    ed_sig_tok = find_opt_by_keyword(tokens, K_ROUTER_SIG_ED25519);
+    ed_cert_tok = find_opt_by_keyword(tokens, K_IDENTITY_ED25519);
+    if (!ed_sig_tok != !ed_cert_tok) {
+      log_warn(LD_DIR, "Router descriptor with only partial ed25519 support");
+      goto err;
+    }
+    if (ed_sig_tok) {
+      tor_assert(ed_cert_tok);
+      if (ed_cert_tok != smartlist_get(tokens, 0) &&
+          ed_cert_tok != smartlist_get(tokens, 1)) {
+        log_warn(LD_DIR, "Ed25519 certificate in wrong position");
+        goto err;
+      }
+      if (ed_sig_tok != smartlist_get(tokens, smartlist_len(tokens)-2)) {
+        log_warn(LD_DIR, "Ed25519 signature in wrong position");
+        goto err;
+      }
+      if (strcmp(ed_cert_tok->object_type, "ED25519 CERT")) {
+        log_warn(LD_DIR, "Wrong object type on identity-ed25519 in decriptor");
+        goto err;
+      }
+
+      uint8_t d256[DIGEST256_LEN];
+      const char *signed_start, *signed_end;
+
+      tor_cert_t *cert = tor_cert_parse(
+                       (const uint8_t*)ed_cert_tok->object_body,
+                       ed_cert_tok->object_size);
+      if (! cert) {
+        log_warn(LD_DIR, "Couldn't parse ed25519 cert");
+        goto err;
+      }
+      router->signing_key_cert = cert;
+      if (cert->cert_type != CERT_TYPE_ID_SIGNING ||
+          ! cert->signing_key_included) {
+        log_warn(LD_DIR, "Invalid form for ed25519 cert");
+        goto err;
+      }
+
+      if (router_get_hash_impl_helper(s, end-s, "router ",
+                                      "\nrouter-sig-ed25519",
+                                      ' ', &signed_start, &signed_end) < 0) {
+        log_warn(LD_DIR, "Can't find ed25519-signed portion of descriptor");
+        goto err;
+      }
+      crypto_digest_t *d = crypto_digest256_new(DIGEST_SHA256);
+      crypto_digest_add_bytes(d, ED_DESC_SIGNATURE_PREFIX,
+        strlen(ED_DESC_SIGNATURE_PREFIX));
+      crypto_digest_add_bytes(d, signed_start, signed_end-signed_start);
+      crypto_digest_get_digest(d, (char*)d256, sizeof(d256));
+      crypto_digest_free(d);
+
+      ed25519_checkable_t check[2];
+      int check_ok[2];
+      if (tor_cert_get_checkable_sig(&check[0], cert, NULL) < 0) {
+        log_err(LD_BUG, "Couldn't create 'checkable' for cert.");
+        goto err;
+      }
+      if (ed25519_signature_from_base64(&check[1].signature,
+                                        ed_sig_tok->args[0])<0) {
+        log_warn(LD_DIR, "Couldn't decode ed25519 signature");
+        goto err;
+      }
+      check[1].pubkey = &cert->signed_key;
+      check[1].msg = d256;
+      check[1].len = DIGEST256_LEN;
+
+      if (ed25519_checksig_batch(check_ok, check, 2) < 0) {
+        log_warn(LD_DIR, "Incorrect ed25519 signatures");
+        goto err;
+      }
+      if (cert->valid_until < time(NULL)) {
+        log_warn(LD_DIR, "Expired ed25519 certificate in router descriptor");
+        goto err;
+      }
+    }
+  }
+
   tok = find_by_keyword(tokens, K_SIGNING_KEY);
   router->identity_pkey = tok->key;
   tok->key = NULL; /* Prevent free */
diff --git a/src/or/routerparse.h b/src/or/routerparse.h
index fc21cb1041..52e53a833c 100644
--- a/src/or/routerparse.h
+++ b/src/or/routerparse.h
@@ -92,5 +92,7 @@ STATIC int routerstatus_parse_guardfraction(const char *guardfraction_str,
                                             routerstatus_t *rs);
 #endif
 
+#define ED_DESC_SIGNATURE_PREFIX "Tor router descriptor signature v1"
+
 #endif
 
diff --git a/src/or/torcert.c b/src/or/torcert.c
index 478ec4d5ac..8fe9c12000 100644
--- a/src/or/torcert.c
+++ b/src/or/torcert.c
@@ -206,3 +206,13 @@ tor_cert_checksig(tor_cert_t *cert,
   }
 }
 
+/** Return a new copy of <b>cert</b> */
+tor_cert_t *
+tor_cert_dup(const tor_cert_t *cert)
+{
+  tor_cert_t *newcert = tor_memdup(cert, sizeof(tor_cert_t));
+  if (cert->encoded)
+    newcert->encoded = tor_memdup(cert->encoded, cert->encoded_len);
+  return newcert;
+}
+
diff --git a/src/or/torcert.h b/src/or/torcert.h
index 7e9c3f5b2d..644cbf812d 100644
--- a/src/or/torcert.h
+++ b/src/or/torcert.h
@@ -62,5 +62,7 @@ int tor_cert_get_checkable_sig(ed25519_checkable_t *checkable_out,
 int tor_cert_checksig(tor_cert_t *cert,
                       const ed25519_public_key_t *pubkey, time_t now);
 
+tor_cert_t *tor_cert_dup(const tor_cert_t *cert);
+
 #endif
 
diff --git a/src/test/test_crypto.c b/src/test/test_crypto.c
index e9fb8bf084..15ba14b3bf 100644
--- a/src/test/test_crypto.c
+++ b/src/test/test_crypto.c
@@ -620,9 +620,18 @@ test_crypto_formats(void *arg)
   for (idx = 0; idx < 10; ++idx) {
     i = base64_encode(data2, 1024, data1, idx);
     tt_int_op(i, OP_GE, 0);
+    tt_int_op(i, OP_EQ, strlen(data2));
     j = base64_decode(data3, 1024, data2, i);
     tt_int_op(j,OP_EQ, idx);
     tt_mem_op(data3,OP_EQ, data1, idx);
+
+    i = base64_encode_nopad(data2, 1024, (uint8_t*)data1, idx);
+    tt_int_op(i, OP_GE, 0);
+    tt_int_op(i, OP_EQ, strlen(data2));
+    tt_assert(! strchr(data2, '='));
+    j = base64_decode_nopad((uint8_t*)data3, 1024, data2, i);
+    tt_int_op(j, OP_EQ, idx);
+    tt_mem_op(data3,OP_EQ, data1, idx);
   }
 
   strlcpy(data1, "Test string that contains 35 chars.", 1024);
@@ -1172,6 +1181,8 @@ test_crypto_ed25519_simple(void *arg)
   tt_int_op(0, OP_EQ, ed25519_public_key_generate(&pub2, &sec1));
 
   tt_mem_op(pub1.pubkey, OP_EQ, pub2.pubkey, sizeof(pub1.pubkey));
+  tt_assert(ed25519_pubkey_eq(&pub1, &pub2));
+  tt_assert(ed25519_pubkey_eq(&pub1, &pub1));
 
   memcpy(&kp1.pubkey, &pub1, sizeof(pub1));
   memcpy(&kp1.seckey, &sec1, sizeof(sec1));
@@ -1191,6 +1202,7 @@ test_crypto_ed25519_simple(void *arg)
   /* Wrong public key doesn't work. */
   tt_int_op(0, OP_EQ, ed25519_public_key_generate(&pub2, &sec2));
   tt_int_op(-1, OP_EQ, ed25519_checksig(&sig2, msg, msg_len, &pub2));
+  tt_assert(! ed25519_pubkey_eq(&pub1, &pub2));
 
   /* Wrong message doesn't work. */
   tt_int_op(0, OP_EQ, ed25519_checksig(&sig2, msg, msg_len, &pub1));
@@ -1329,9 +1341,10 @@ test_crypto_ed25519_test_vectors(void *arg)
 static void
 test_crypto_ed25519_encode(void *arg)
 {
-  char buf[ED25519_BASE64_LEN+1];
+  char buf[ED25519_SIG_BASE64_LEN+1];
   ed25519_keypair_t kp;
   ed25519_public_key_t pk;
+  ed25519_signature_t sig1, sig2;
   char *mem_op_hex_tmp = NULL;
   (void) arg;
 
@@ -1342,6 +1355,11 @@ test_crypto_ed25519_encode(void *arg)
   tt_int_op(0, OP_EQ, ed25519_public_from_base64(&pk, buf));
   tt_mem_op(kp.pubkey.pubkey, OP_EQ, pk.pubkey, ED25519_PUBKEY_LEN);
 
+  tt_int_op(0, OP_EQ, ed25519_sign(&sig1, (const uint8_t*)"ABC", 3, &kp));
+  tt_int_op(0, OP_EQ, ed25519_signature_to_base64(buf, &sig1));
+  tt_int_op(0, OP_EQ, ed25519_signature_from_base64(&sig2, buf));
+  tt_mem_op(sig1.sig, OP_EQ, sig2.sig, ED25519_SIG_LEN);
+
   /* Test known value. */
   tt_int_op(0, OP_EQ, ed25519_public_from_base64(&pk,
                              "lVIuIctLjbGZGU5wKMNXxXlSE3cW4kaqkqm04u6pxvM"));
diff --git a/src/test/test_dir.c b/src/test/test_dir.c
index a949f5de73..85ca40f3de 100644
--- a/src/test/test_dir.c
+++ b/src/test/test_dir.c
@@ -14,6 +14,7 @@
 #define NETWORKSTATUS_PRIVATE
 #include "or.h"
 #include "config.h"
+#include "crypto_ed25519.h"
 #include "directory.h"
 #include "dirserv.h"
 #include "dirvote.h"
@@ -23,6 +24,7 @@
 #include "routerlist.h"
 #include "routerparse.h"
 #include "test.h"
+#include "torcert.h"
 
 static void
 test_dir_nicknames(void *arg)
@@ -89,6 +91,7 @@ test_dir_formats(void *arg)
   routerlist_t *dir1 = NULL, *dir2 = NULL;
   or_options_t *options = get_options_mutable();
   const addr_policy_t *p;
+  time_t now = time(NULL);
 
   (void)arg;
   pk1 = pk_generate(0);
@@ -127,6 +130,22 @@ test_dir_formats(void *arg)
   ex2->prt_min = ex2->prt_max = 24;
   r2 = tor_malloc_zero(sizeof(routerinfo_t));
   r2->addr = 0x0a030201u; /* 10.3.2.1 */
+  ed25519_keypair_t kp1, kp2;
+  ed25519_secret_key_from_seed(&kp1.seckey,
+                          (const uint8_t*)"YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY");
+  ed25519_public_key_generate(&kp1.pubkey, &kp1.seckey);
+  ed25519_secret_key_from_seed(&kp2.seckey,
+                          (const uint8_t*)"XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX");
+  ed25519_public_key_generate(&kp2.pubkey, &kp2.seckey);
+  r2->signing_key_cert = tor_cert_create(&kp1,
+                                         CERT_TYPE_ID_SIGNING,
+                                         &kp2.pubkey,
+                                         now, 86400,
+                                         CERT_FLAG_INCLUDE_SIGNING_KEY);
+  char cert_buf[256];
+  base64_encode(cert_buf, sizeof(cert_buf),
+                (const char*)r2->signing_key_cert->encoded,
+                r2->signing_key_cert->encoded_len);
   r2->platform = tor_strdup(platform);
   r2->cache_info.published_on = 5;
   r2->or_port = 9005;
@@ -150,7 +169,7 @@ test_dir_formats(void *arg)
   /* XXXX025 router_dump_to_string should really take this from ri.*/
   options->ContactInfo = tor_strdup("Magri White "
                                     "<magri@elsewhere.example.com>");
-  buf = router_dump_router_to_string(r1, pk2);
+  buf = router_dump_router_to_string(r1, pk2, NULL);
   tor_free(options->ContactInfo);
   tt_assert(buf);
 
@@ -183,7 +202,7 @@ test_dir_formats(void *arg)
   tt_str_op(buf,OP_EQ, buf2);
   tor_free(buf);
 
-  buf = router_dump_router_to_string(r1, pk2);
+  buf = router_dump_router_to_string(r1, pk2, NULL);
   tt_assert(buf);
   cp = buf;
   rp1 = router_parse_entry_from_string((const char*)cp,NULL,1,0,NULL,NULL);
@@ -201,6 +220,10 @@ test_dir_formats(void *arg)
 
   strlcpy(buf2,
           "router Fred 10.3.2.1 9005 0 0\n"
+          "identity-ed25519\n"
+          "-----BEGIN ED25519 CERT-----\n", sizeof(buf2));
+  strlcat(buf2, cert_buf, sizeof(buf2));
+  strlcat(buf2, "-----END ED25519 CERT-----\n"
           "platform Tor "VERSION" on ", sizeof(buf2));
   strlcat(buf2, get_uname(), sizeof(buf2));
   strlcat(buf2, "\n"
@@ -219,15 +242,16 @@ test_dir_formats(void *arg)
   strlcat(buf2, "ntor-onion-key "
           "skyinAnvardNostarsNomoonNowindormistsorsnow=\n", sizeof(buf2));
   strlcat(buf2, "accept *:80\nreject 18.0.0.0/8:24\n", sizeof(buf2));
-  strlcat(buf2, "router-signature\n", sizeof(buf2));
+  strlcat(buf2, "router-sig-ed25519 ", sizeof(buf2));
 
-  buf = router_dump_router_to_string(r2, pk1);
+  buf = router_dump_router_to_string(r2, pk1, &kp2);
+  tt_assert(buf);
   buf[strlen(buf2)] = '\0'; /* Don't compare the sig; it's never the same
                              * twice */
   tt_str_op(buf,OP_EQ, buf2);
   tor_free(buf);
 
-  buf = router_dump_router_to_string(r2, pk1);
+  buf = router_dump_router_to_string(r2, pk1, NULL);
   cp = buf;
   rp2 = router_parse_entry_from_string((const char*)cp,NULL,1,0,NULL,NULL);
   tt_assert(rp2);
diff --git a/src/test/test_routerkeys.c b/src/test/test_routerkeys.c
index 63284b798b..8780213a29 100644
--- a/src/test/test_routerkeys.c
+++ b/src/test/test_routerkeys.c
@@ -90,6 +90,7 @@ test_routerkeys_ed_certs(void *args)
   tor_cert_t *parsed_cert[2] = {NULL, NULL};
   time_t now = 1412094534;
   uint8_t *junk = NULL;
+  char *base64 = NULL;
 
   tt_int_op(0,==,ed25519_keypair_generate(&kp1, 0));
   tt_int_op(0,==,ed25519_keypair_generate(&kp2, 0));
@@ -186,6 +187,7 @@ test_routerkeys_ed_certs(void *args)
   tor_cert_free(parsed_cert[0]);
   tor_cert_free(parsed_cert[1]);
   tor_free(junk);
+  tor_free(base64);
 }
 
 static void