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-rw-r--r--src/common/crypto_curve25519.c174
-rw-r--r--src/common/crypto_curve25519.h14
-rw-r--r--src/common/crypto_ed25519.c353
-rw-r--r--src/common/crypto_ed25519.h116
-rw-r--r--src/common/crypto_format.c22
-rw-r--r--src/common/include.am7
6 files changed, 644 insertions, 42 deletions
diff --git a/src/common/crypto_curve25519.c b/src/common/crypto_curve25519.c
index 9e83440e16..44b280a346 100644
--- a/src/common/crypto_curve25519.c
+++ b/src/common/crypto_curve25519.c
@@ -8,6 +8,7 @@
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
+#include "container.h"
#include "crypto.h"
#include "crypto_curve25519.h"
#include "util.h"
@@ -63,26 +64,44 @@ curve25519_public_key_is_ok(const curve25519_public_key_t *key)
return !safe_mem_is_zero(key->public_key, CURVE25519_PUBKEY_LEN);
}
-/** Generate a new keypair and return the secret key. If <b>extra_strong</b>
- * is true, this key is possibly going to get used more than once, so
- * use a better-than-usual RNG. Return 0 on success, -1 on failure. */
+/**
+ * Generate CURVE25519_SECKEY_LEN random bytes in <b>out</b>. If
+ * <b>extra_strong</b> is true, this key is possibly going to get used more
+ * than once, so use a better-than-usual RNG. Return 0 on success, -1 on
+ * failure.
+ *
+ * This function does not adjust the output of the RNG at all; the will caller
+ * will need to clear or set the appropriate bits to make curve25519 work.
+ */
int
-curve25519_secret_key_generate(curve25519_secret_key_t *key_out,
- int extra_strong)
+curve25519_rand_seckey_bytes(uint8_t *out, int extra_strong)
{
uint8_t k_tmp[CURVE25519_SECKEY_LEN];
- if (crypto_rand((char*)key_out->secret_key, CURVE25519_SECKEY_LEN) < 0)
+ if (crypto_rand((char*)out, CURVE25519_SECKEY_LEN) < 0)
return -1;
if (extra_strong && !crypto_strongest_rand(k_tmp, CURVE25519_SECKEY_LEN)) {
/* If they asked for extra-strong entropy and we have some, use it as an
* HMAC key to improve not-so-good entropy rather than using it directly,
* just in case the extra-strong entropy is less amazing than we hoped. */
- crypto_hmac_sha256((char *)key_out->secret_key,
- (const char *)k_tmp, sizeof(k_tmp),
- (const char *)key_out->secret_key, CURVE25519_SECKEY_LEN);
+ crypto_hmac_sha256((char*) out,
+ (const char *)k_tmp, sizeof(k_tmp),
+ (const char *)out, CURVE25519_SECKEY_LEN);
}
memwipe(k_tmp, 0, sizeof(k_tmp));
+ return 0;
+}
+
+/** Generate a new keypair and return the secret key. If <b>extra_strong</b>
+ * is true, this key is possibly going to get used more than once, so
+ * use a better-than-usual RNG. Return 0 on success, -1 on failure. */
+int
+curve25519_secret_key_generate(curve25519_secret_key_t *key_out,
+ int extra_strong)
+{
+ if (curve25519_rand_seckey_bytes(key_out->secret_key, extra_strong) < 0)
+ return -1;
+
key_out->secret_key[0] &= 248;
key_out->secret_key[31] &= 127;
key_out->secret_key[31] |= 64;
@@ -109,69 +128,142 @@ curve25519_keypair_generate(curve25519_keypair_t *keypair_out,
return 0;
}
+/** Write the <b>datalen</b> bytes from <b>data</b> to the file named
+ * <b>fname</b> in the tagged-data format. This format contains a
+ * 32-byte header, followed by the data itself. The header is the
+ * NUL-padded string "== <b>typestring</b>: <b>tag</b> ==". The length
+ * of <b>typestring</b> and <b>tag</b> must therefore be no more than
+ * 24.
+ **/
int
-curve25519_keypair_write_to_file(const curve25519_keypair_t *keypair,
- const char *fname,
- const char *tag)
+crypto_write_tagged_contents_to_file(const char *fname,
+ const char *typestring,
+ const char *tag,
+ const uint8_t *data,
+ size_t datalen)
{
- char contents[32 + CURVE25519_SECKEY_LEN + CURVE25519_PUBKEY_LEN];
- int r;
+ char header[32];
+ smartlist_t *chunks = smartlist_new();
+ sized_chunk_t ch0, ch1;
+ int r = -1;
- memset(contents, 0, sizeof(contents));
- tor_snprintf(contents, sizeof(contents), "== c25519v1: %s ==", tag);
- tor_assert(strlen(contents) <= 32);
- memcpy(contents+32, keypair->seckey.secret_key, CURVE25519_SECKEY_LEN);
- memcpy(contents+32+CURVE25519_SECKEY_LEN,
- keypair->pubkey.public_key, CURVE25519_PUBKEY_LEN);
+ memset(header, 0, sizeof(header));
+ if (tor_snprintf(header, sizeof(header),
+ "== %s: %s ==", typestring, tag) < 0)
+ goto end;
+ ch0.bytes = header;
+ ch0.len = 32;
+ ch1.bytes = (const char*) data;
+ ch1.len = datalen;
+ smartlist_add(chunks, &ch0);
+ smartlist_add(chunks, &ch1);
- r = write_bytes_to_file(fname, contents, sizeof(contents), 1);
+ r = write_chunks_to_file(fname, chunks, 1, 0);
- memwipe(contents, 0, sizeof(contents));
+ end:
+ smartlist_free(chunks);
return r;
}
-int
-curve25519_keypair_read_from_file(curve25519_keypair_t *keypair_out,
- char **tag_out,
- const char *fname)
+/** Read a tagged-data file from <b>fname</b> into the
+ * <b>data_out_len</b>-byte buffer in <b>data_out</b>. Check that the
+ * typestring matches <b>typestring</b>; store the tag into a newly allocated
+ * string in <b>tag_out</b>. Return -1 on failure, and the number of bytes of
+ * data on success. */
+ssize_t
+crypto_read_tagged_contents_from_file(const char *fname,
+ const char *typestring,
+ char **tag_out,
+ uint8_t *data_out,
+ ssize_t data_out_len)
{
char prefix[33];
- char *content;
+ char *content = NULL;
struct stat st;
- int r = -1;
+ ssize_t r = -1;
*tag_out = NULL;
-
st.st_size = 0;
content = read_file_to_str(fname, RFTS_BIN|RFTS_IGNORE_MISSING, &st);
if (! content)
goto end;
- if (st.st_size != 32 + CURVE25519_SECKEY_LEN + CURVE25519_PUBKEY_LEN)
+ if (st.st_size < 32 || st.st_size > 32 + data_out_len)
goto end;
memcpy(prefix, content, 32);
- prefix[32] = '\0';
- if (strcmpstart(prefix, "== c25519v1: ") ||
- strcmpend(prefix, " =="))
+ prefix[32] = 0;
+ /* Check type, extract tag. */
+ if (strcmpstart(prefix, "== ") || strcmpend(prefix, " ==") ||
+ ! tor_mem_is_zero(prefix+strlen(prefix), 32-strlen(prefix)))
+ goto end;
+
+ if (strcmpstart(prefix+3, typestring) ||
+ 3+strlen(typestring) >= 32 ||
+ strcmpstart(prefix+3+strlen(typestring), ": "))
goto end;
- *tag_out = tor_strndup(prefix+strlen("== c25519v1: "),
- strlen(prefix) - strlen("== c25519v1: =="));
+ *tag_out = tor_strndup(prefix+5+strlen(typestring),
+ strlen(prefix)-8-strlen(typestring));
+
+ memcpy(data_out, content+32, st.st_size-32);
+ r = st.st_size - 32;
+
+ end:
+ if (content)
+ memwipe(content, 0, st.st_size);
+ tor_free(content);
+ return r;
+}
+
+/** DOCDOC */
+int
+curve25519_keypair_write_to_file(const curve25519_keypair_t *keypair,
+ const char *fname,
+ const char *tag)
+{
+ uint8_t contents[CURVE25519_SECKEY_LEN + CURVE25519_PUBKEY_LEN];
+ int r;
+
+ memcpy(contents, keypair->seckey.secret_key, CURVE25519_SECKEY_LEN);
+ memcpy(contents+CURVE25519_SECKEY_LEN,
+ keypair->pubkey.public_key, CURVE25519_PUBKEY_LEN);
+
+ r = crypto_write_tagged_contents_to_file(fname,
+ "c25519v1",
+ tag,
+ contents,
+ sizeof(contents));
+
+ memwipe(contents, 0, sizeof(contents));
+ return r;
+}
+
+/** DOCDOC */
+int
+curve25519_keypair_read_from_file(curve25519_keypair_t *keypair_out,
+ char **tag_out,
+ const char *fname)
+{
+ uint8_t content[CURVE25519_SECKEY_LEN + CURVE25519_PUBKEY_LEN];
+ ssize_t len;
+ int r = -1;
+
+ len = crypto_read_tagged_contents_from_file(fname, "c25519v1", tag_out,
+ content, sizeof(content));
+ if (len != sizeof(content))
+ goto end;
- memcpy(keypair_out->seckey.secret_key, content+32, CURVE25519_SECKEY_LEN);
+ memcpy(keypair_out->seckey.secret_key, content, CURVE25519_SECKEY_LEN);
curve25519_public_key_generate(&keypair_out->pubkey, &keypair_out->seckey);
if (tor_memneq(keypair_out->pubkey.public_key,
- content + 32 + CURVE25519_SECKEY_LEN,
+ content + CURVE25519_SECKEY_LEN,
CURVE25519_PUBKEY_LEN))
goto end;
r = 0;
end:
- if (content) {
- memwipe(content, 0, (size_t) st.st_size);
- tor_free(content);
- }
+ memwipe(content, 0, sizeof(content));
if (r != 0) {
memset(keypair_out, 0, sizeof(*keypair_out));
tor_free(*tag_out);
diff --git a/src/common/crypto_curve25519.h b/src/common/crypto_curve25519.h
index 57018ac2f5..404f99c18e 100644
--- a/src/common/crypto_curve25519.h
+++ b/src/common/crypto_curve25519.h
@@ -57,6 +57,8 @@ int curve25519_keypair_read_from_file(curve25519_keypair_t *keypair_out,
char **tag_out,
const char *fname);
+int curve25519_rand_seckey_bytes(uint8_t *out, int extra_strong);
+
#ifdef CRYPTO_CURVE25519_PRIVATE
STATIC int curve25519_impl(uint8_t *output, const uint8_t *secret,
const uint8_t *basepoint);
@@ -70,5 +72,17 @@ int curve25519_public_from_base64(curve25519_public_key_t *pkey,
int curve25519_public_to_base64(char *output,
const curve25519_public_key_t *pkey);
+int crypto_write_tagged_contents_to_file(const char *fname,
+ const char *typestring,
+ const char *tag,
+ const uint8_t *data,
+ size_t datalen);
+
+ssize_t crypto_read_tagged_contents_from_file(const char *fname,
+ const char *typestring,
+ char **tag_out,
+ uint8_t *data_out,
+ ssize_t data_out_len);
+
#endif
diff --git a/src/common/crypto_ed25519.c b/src/common/crypto_ed25519.c
new file mode 100644
index 0000000000..408c12b4fd
--- /dev/null
+++ b/src/common/crypto_ed25519.c
@@ -0,0 +1,353 @@
+/* Copyright (c) 2013, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/* Wrapper code for an ed25519 implementation. */
+
+#include "orconfig.h"
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+
+#include "crypto.h"
+
+#include "crypto_curve25519.h"
+#include "crypto_ed25519.h"
+#include "torlog.h"
+#include "util.h"
+
+#include "ed25519/ref10/ed25519_ref10.h"
+
+#include <openssl/sha.h>
+
+/**
+ * Initialize a new ed25519 secret key in <b>seckey_out</b>. If
+ * <b>extra_strong</b>, take the RNG inputs directly from the operating
+ * system. Return 0 on success, -1 on failure.
+ */
+int
+ed25519_secret_key_generate(ed25519_secret_key_t *seckey_out,
+ int extra_strong)
+{
+ int r;
+ uint8_t seed[32];
+ if (! extra_strong || crypto_strongest_rand(seed, sizeof(seed)) < 0)
+ crypto_rand((char*)seed, sizeof(seed));
+
+ r = ed25519_ref10_seckey_expand(seckey_out->seckey, seed);
+ memwipe(seed, 0, sizeof(seed));
+
+ return r < 0 ? -1 : 0;
+}
+
+/**
+ * Given a 32-byte random seed in <b>seed</b>, expand it into an ed25519
+ * secret key in <b>seckey_out</b>. Return 0 on success, -1 on failure.
+ */
+int
+ed25519_secret_key_from_seed(ed25519_secret_key_t *seckey_out,
+ const uint8_t *seed)
+{
+ if (ed25519_ref10_seckey_expand(seckey_out->seckey, seed) < 0)
+ return -1;
+ return 0;
+}
+
+/**
+ * Given a secret key in <b>seckey</b>, expand it into an
+ * ed25519 public key. Return 0 on success, -1 on failure.
+ */
+int
+ed25519_public_key_generate(ed25519_public_key_t *pubkey_out,
+ const ed25519_secret_key_t *seckey)
+{
+ if (ed25519_ref10_pubkey(pubkey_out->pubkey, seckey->seckey) < 0)
+ return -1;
+ return 0;
+}
+
+/** Generate a new ed25519 keypair in <b>keypair_out</b>. If
+ * <b>extra_strong</b> is set, try to mix some system entropy into the key
+ * generation process. Return 0 on success, -1 on failure. */
+int
+ed25519_keypair_generate(ed25519_keypair_t *keypair_out, int extra_strong)
+{
+ if (ed25519_secret_key_generate(&keypair_out->seckey, extra_strong) < 0)
+ return -1;
+ if (ed25519_public_key_generate(&keypair_out->pubkey,
+ &keypair_out->seckey)<0)
+ return -1;
+ return 0;
+}
+
+/**
+ * Set <b>signature_out</b> to a signature of the <b>len</b>-byte message
+ * <b>msg</b>, using the secret and public key in <b>keypair</b>.
+ */
+int
+ed25519_sign(ed25519_signature_t *signature_out,
+ const uint8_t *msg, size_t len,
+ const ed25519_keypair_t *keypair)
+{
+
+ if (ed25519_ref10_sign(signature_out->sig, msg, len,
+ keypair->seckey.seckey,
+ keypair->pubkey.pubkey) < 0) {
+ return -1;
+ }
+
+ return 0;
+}
+
+/**
+ * Check whether if <b>signature</b> is a valid signature for the
+ * <b>len</b>-byte message in <b>msg</b> made with the key <b>pubkey</b>.
+ *
+ * Return 0 if the signature is valid; -1 if it isn't.
+ */
+int
+ed25519_checksig(const ed25519_signature_t *signature,
+ const uint8_t *msg, size_t len,
+ const ed25519_public_key_t *pubkey)
+{
+ return
+ ed25519_ref10_open(signature->sig, msg, len, pubkey->pubkey) < 0 ? -1 : 0;
+}
+
+/** Validate every signature among those in <b>checkable</b>, which contains
+ * exactly <b>n_checkable</b> elements. If <b>okay_out</b> is non-NULL, set
+ * the i'th element of <b>okay_out</b> to 1 if the i'th element of
+ * <b>checkable</b> is valid, and to 0 otherwise. Return 0 if every signature
+ * was valid. Otherwise return -N, where N is the number of invalid
+ * signatures.
+ */
+int
+ed25519_checksig_batch(int *okay_out,
+ const ed25519_checkable_t *checkable,
+ int n_checkable)
+{
+ int res, i;
+
+ res = 0;
+ for (i = 0; i < n_checkable; ++i) {
+ const ed25519_checkable_t *ch = &checkable[i];
+ int r = ed25519_checksig(&ch->signature, ch->msg, ch->len, ch->pubkey);
+ if (r < 0)
+ --res;
+ if (okay_out)
+ okay_out[i] = (r == 0);
+ }
+
+#if 0
+ /* This is how we'd do it if we were using ed25519_donna. I'll keep this
+ * code around here in case we ever do that. */
+ const uint8_t **ms;
+ size_t *lens;
+ const uint8_t **pks;
+ const uint8_t **sigs;
+ int *oks;
+
+ ms = tor_malloc(sizeof(uint8_t*)*n_checkable);
+ lens = tor_malloc(sizeof(size_t)*n_checkable);
+ pks = tor_malloc(sizeof(uint8_t*)*n_checkable);
+ sigs = tor_malloc(sizeof(uint8_t*)*n_checkable);
+ oks = okay_out ? okay_out : tor_malloc(sizeof(int)*n_checkable);
+
+ for (i = 0; i < n_checkable; ++i) {
+ ms[i] = checkable[i].msg;
+ lens[i] = checkable[i].len;
+ pks[i] = checkable[i].pubkey->pubkey;
+ sigs[i] = checkable[i].signature.sig;
+ oks[i] = 0;
+ }
+
+ ed25519_sign_open_batch_donna_fb(ms, lens, pks, sigs, n_checkable, oks);
+
+ res = 0;
+ for (i = 0; i < n_checkable; ++i) {
+ if (!oks[i])
+ --res;
+ }
+
+ tor_free(ms);
+ tor_free(lens);
+ tor_free(pks);
+ if (! okay_out)
+ tor_free(oks);
+#endif
+
+ return res;
+}
+
+/**
+ * Given a curve25519 keypair in <b>inp</b>, generate a corresponding
+ * ed25519 keypair in <b>out</b>, and set <b>signbit_out</b> to the
+ * sign bit of the X coordinate of the ed25519 key.
+ *
+ * NOTE THAT IT IS PROBABLY NOT SAFE TO USE THE GENERATED KEY FOR ANYTHING
+ * OUTSIDE OF WHAT'S PRESENTED IN PROPOSAL 228. In particular, it's probably
+ * not a great idea to use it to sign attacker-supplied anything.
+ */
+int
+ed25519_keypair_from_curve25519_keypair(ed25519_keypair_t *out,
+ int *signbit_out,
+ const curve25519_keypair_t *inp)
+{
+ const char string[] = "Derive high part of ed25519 key from curve25519 key";
+ ed25519_public_key_t pubkey_check;
+ SHA512_CTX ctx;
+ uint8_t sha512_output[64];
+
+ memcpy(out->seckey.seckey, inp->seckey.secret_key, 32);
+ SHA512_Init(&ctx);
+ SHA512_Update(&ctx, out->seckey.seckey, 32);
+ SHA512_Update(&ctx, string, sizeof(string));
+ SHA512_Final(sha512_output, &ctx);
+ memcpy(out->seckey.seckey + 32, sha512_output, 32);
+
+ ed25519_public_key_generate(&out->pubkey, &out->seckey);
+
+ *signbit_out = out->pubkey.pubkey[31] >> 7;
+
+ ed25519_public_key_from_curve25519_public_key(&pubkey_check, &inp->pubkey,
+ *signbit_out);
+
+ tor_assert(fast_memeq(pubkey_check.pubkey, out->pubkey.pubkey, 32));
+
+ memwipe(&pubkey_check, 0, sizeof(pubkey_check));
+ memwipe(&ctx, 0, sizeof(ctx));
+ memwipe(sha512_output, 0, sizeof(sha512_output));
+
+ return 0;
+}
+
+/**
+ * Given a curve25519 public key and sign bit of X coordinate of the ed25519
+ * public key, generate the corresponding ed25519 public key.
+ */
+int
+ed25519_public_key_from_curve25519_public_key(ed25519_public_key_t *pubkey,
+ const curve25519_public_key_t *pubkey_in,
+ int signbit)
+{
+ return ed25519_ref10_pubkey_from_curve25519_pubkey(pubkey->pubkey,
+ pubkey_in->public_key,
+ signbit);
+}
+
+/**
+ * Given an ed25519 keypair in <b>inp</b>, generate a corresponding
+ * ed25519 keypair in <b>out</b>, blinded by the corresponding 32-byte input
+ * in 'param'.
+ *
+ * Tor uses key blinding for the "next-generation" hidden services design:
+ * service descriptors are encrypted with a key derived from the service's
+ * long-term public key, and then signed with (and stored at a position
+ * indexed by) a short-term key derived by blinding the long-term keys.
+ */
+int
+ed25519_keypair_blind(ed25519_keypair_t *out,
+ const ed25519_keypair_t *inp,
+ const uint8_t *param)
+{
+ ed25519_public_key_t pubkey_check;
+
+ ed25519_ref10_blind_secret_key(out->seckey.seckey,
+ inp->seckey.seckey, param);
+
+ ed25519_public_blind(&pubkey_check, &inp->pubkey, param);
+ ed25519_public_key_generate(&out->pubkey, &out->seckey);
+
+ tor_assert(fast_memeq(pubkey_check.pubkey, out->pubkey.pubkey, 32));
+
+ memwipe(&pubkey_check, 0, sizeof(pubkey_check));
+
+ return 0;
+}
+
+/**
+ * Given an ed25519 public key in <b>inp</b>, generate a corresponding blinded
+ * public key in <b>out</b>, blinded with the 32-byte parameter in
+ * <b>param</b>. Return 0 on sucess, -1 on railure.
+ */
+int
+ed25519_public_blind(ed25519_public_key_t *out,
+ const ed25519_public_key_t *inp,
+ const uint8_t *param)
+{
+ ed25519_ref10_blind_public_key(out->pubkey, inp->pubkey, param);
+ return 0;
+}
+
+/**
+ * Store seckey unencrypted to <b>filename</b>, marking it with <b>tag</b>.
+ * Return 0 on success, -1 on failure.
+ */
+int
+ed25519_seckey_write_to_file(const ed25519_secret_key_t *seckey,
+ const char *filename,
+ const char *tag)
+{
+ return crypto_write_tagged_contents_to_file(filename,
+ "ed25519v1-secret",
+ tag,
+ seckey->seckey,
+ sizeof(seckey->seckey));
+}
+
+/**
+ * Read seckey unencrypted from <b>filename</b>, storing it into
+ * <b>seckey_out</b>. Set *<b>tag_out</> to the tag it was marked with.
+ * Return 0 on success, -1 on failure.
+ */
+int
+ed25519_seckey_read_from_file(ed25519_secret_key_t *seckey_out,
+ char **tag_out,
+ const char *filename)
+{
+ ssize_t len;
+
+ len = crypto_read_tagged_contents_from_file(filename, "ed25519v1-secret",
+ tag_out, seckey_out->seckey,
+ sizeof(seckey_out->seckey));
+ if (len != sizeof(seckey_out->seckey))
+ return -1;
+
+ return 0;
+}
+
+/**
+ * Store pubkey unencrypted to <b>filename</b>, marking it with <b>tag</b>.
+ * Return 0 on success, -1 on failure.
+ */
+int
+ed25519_pubkey_write_to_file(const ed25519_public_key_t *pubkey,
+ const char *filename,
+ const char *tag)
+{
+ return crypto_write_tagged_contents_to_file(filename,
+ "ed25519v1-public",
+ tag,
+ pubkey->pubkey,
+ sizeof(pubkey->pubkey));
+}
+
+/**
+ * Store pubkey unencrypted to <b>filename</b>, marking it with <b>tag</b>.
+ * Return 0 on success, -1 on failure.
+ */
+int
+ed25519_pubkey_read_from_file(ed25519_public_key_t *pubkey_out,
+ char **tag_out,
+ const char *filename)
+{
+ ssize_t len;
+
+ len = crypto_read_tagged_contents_from_file(filename, "ed25519v1-public",
+ tag_out, pubkey_out->pubkey,
+ sizeof(pubkey_out->pubkey));
+ if (len != sizeof(pubkey_out->pubkey))
+ return -1;
+
+ return 0;
+}
+
diff --git a/src/common/crypto_ed25519.h b/src/common/crypto_ed25519.h
new file mode 100644
index 0000000000..13b05c7c1e
--- /dev/null
+++ b/src/common/crypto_ed25519.h
@@ -0,0 +1,116 @@
+/* Copyright (c) 2012-2013, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_CRYPTO_ED25519_H
+#define TOR_CRYPTO_ED25519_H
+
+#include "testsupport.h"
+#include "torint.h"
+
+#define ED25519_PUBKEY_LEN 32
+#define ED25519_SECKEY_LEN 64
+#define ED25519_SECKEY_SEED_LEN 32
+#define ED25519_SIG_LEN 64
+
+/** An Ed25519 signature. */
+typedef struct {
+ uint8_t sig[ED25519_SIG_LEN];
+} ed25519_signature_t;
+
+/** An Ed25519 public key */
+typedef struct {
+ uint8_t pubkey[ED25519_PUBKEY_LEN];
+} ed25519_public_key_t;
+
+/** An Ed25519 secret key */
+typedef struct {
+ /** Note that we store secret keys in an expanded format that doesn't match
+ * the format from standard ed25519. Ed25519 stores a 32-byte value k and
+ * expands it into a 64-byte H(k), using the first 32 bytes for a multiplier
+ * of the base point, and second 32 bytes as an input to a hash function
+ * for deriving r. But because we implement key blinding, we need to store
+ * keys in the 64-byte expanded form. */
+ uint8_t seckey[ED25519_SECKEY_LEN];
+} ed25519_secret_key_t;
+
+/** An Ed25519 keypair. */
+typedef struct {
+ ed25519_public_key_t pubkey;
+ ed25519_secret_key_t seckey;
+} ed25519_keypair_t;
+
+#ifdef CURVE25519_ENABLED
+int ed25519_secret_key_generate(ed25519_secret_key_t *seckey_out,
+ int extra_strong);
+int ed25519_secret_key_from_seed(ed25519_secret_key_t *seckey_out,
+ const uint8_t *seed);
+
+int ed25519_public_key_generate(ed25519_public_key_t *pubkey_out,
+ const ed25519_secret_key_t *seckey);
+int ed25519_keypair_generate(ed25519_keypair_t *keypair_out, int extra_strong);
+int ed25519_sign(ed25519_signature_t *signature_out,
+ const uint8_t *msg, size_t len,
+ const ed25519_keypair_t *key);
+int ed25519_checksig(const ed25519_signature_t *signature,
+ const uint8_t *msg, size_t len,
+ const ed25519_public_key_t *pubkey);
+
+/**
+ * A collection of information necessary to check an Ed25519 signature. Used
+ * for batch verification.
+ */
+typedef struct {
+ /** The public key that supposedly generated the signature. */
+ ed25519_public_key_t *pubkey;
+ /** The signature to check. */
+ ed25519_signature_t signature;
+ /** The message that the signature is supposed to have been applied to. */
+ const uint8_t *msg;
+ /** The length of the message. */
+ size_t len;
+} ed25519_checkable_t;
+
+int ed25519_checksig_batch(int *okay_out,
+ const ed25519_checkable_t *checkable,
+ int n_checkable);
+
+int ed25519_keypair_from_curve25519_keypair(ed25519_keypair_t *out,
+ int *signbit_out,
+ const curve25519_keypair_t *inp);
+
+int ed25519_public_key_from_curve25519_public_key(ed25519_public_key_t *pubkey,
+ const curve25519_public_key_t *pubkey_in,
+ int signbit);
+int ed25519_keypair_blind(ed25519_keypair_t *out,
+ const ed25519_keypair_t *inp,
+ const uint8_t *param);
+int ed25519_public_blind(ed25519_public_key_t *out,
+ const ed25519_public_key_t *inp,
+ const uint8_t *param);
+
+#endif
+
+#define ED25519_BASE64_LEN 43
+
+int ed25519_public_from_base64(ed25519_public_key_t *pkey,
+ const char *input);
+int ed25519_public_to_base64(char *output,
+ const ed25519_public_key_t *pkey);
+
+/* XXXX read encrypted, write encrypted. */
+
+int ed25519_seckey_write_to_file(const ed25519_secret_key_t *seckey,
+ const char *filename,
+ const char *tag);
+int ed25519_seckey_read_from_file(ed25519_secret_key_t *seckey_out,
+ char **tag_out,
+ const char *filename);
+int ed25519_pubkey_write_to_file(const ed25519_public_key_t *pubkey,
+ const char *filename,
+ const char *tag);
+int ed25519_pubkey_read_from_file(ed25519_public_key_t *pubkey_out,
+ char **tag_out,
+ const char *filename);
+
+#endif
+
diff --git a/src/common/crypto_format.c b/src/common/crypto_format.c
index be669c8d2b..a9f104cab2 100644
--- a/src/common/crypto_format.c
+++ b/src/common/crypto_format.c
@@ -9,6 +9,7 @@
#endif
#include "crypto.h"
#include "crypto_curve25519.h"
+#include "crypto_ed25519.h"
#include "util.h"
#include "torlog.h"
@@ -43,3 +44,24 @@ curve25519_public_from_base64(curve25519_public_key_t *pkey,
}
}
+/** Try to decode the string <b>input</b> into an ed25519 public key. On
+ * success, store the value in <b>pkey</b> and return 0. Otherwise return
+ * -1. */
+int
+ed25519_public_from_base64(ed25519_public_key_t *pkey,
+ const char *input)
+{
+ return digest256_from_base64((char*)pkey->pubkey, input);
+}
+
+/** Encode the public key <b>pkey</b> into the buffer at <b>output</b>,
+ * which must have space for ED25519_BASE64_LEN bytes of encoded key,
+ * plus one byte for a terminating NUL. Return 0 on success, -1 on failure.
+ */
+int
+ed25519_public_to_base64(char *output,
+ const ed25519_public_key_t *pkey)
+{
+ return digest256_to_base64(output, (const char *)pkey->pubkey);
+}
+
diff --git a/src/common/include.am b/src/common/include.am
index d669cf473a..5c000e86f3 100644
--- a/src/common/include.am
+++ b/src/common/include.am
@@ -52,8 +52,12 @@ LIBDONNA=
endif
endif
+LIBDONNA += $(LIBED25519_REF10)
+
if CURVE25519_ENABLED
-libcrypto_extra_source=src/common/crypto_curve25519.c
+libcrypto_extra_source = \
+ src/common/crypto_curve25519.c \
+ src/common/crypto_ed25519.c
endif
LIBOR_A_SOURCES = \
@@ -114,6 +118,7 @@ COMMONHEADERS = \
src/common/container.h \
src/common/crypto.h \
src/common/crypto_curve25519.h \
+ src/common/crypto_ed25519.h \
src/common/crypto_pwbox.h \
src/common/crypto_s2k.h \
src/common/di_ops.h \