Add support for Poly1305 in EVP_PKEY

Add Poly1305 as a "signed" digest.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2128)

3 files changed, 261 insertions, 0 deletions

diff --git a/crypto/poly1305/build.info b/crypto/poly1305/build.info
index 358fa82212..dae9aa467d 100644
--- a/crypto/poly1305/build.info
+++ b/crypto/poly1305/build.info
@@ -1,5 +1,7 @@
 LIBS=../../libcrypto
 SOURCE[../../libcrypto]=\
+        poly1305_pmeth.c \
+        poly1305_ameth.c \
         poly1305.c {- $target{poly1305_asm_src} -}
 
 GENERATE[poly1305-sparcv9.S]=asm/poly1305-sparcv9.pl $(PERLASM_SCHEME)
diff --git a/crypto/poly1305/poly1305_ameth.c b/crypto/poly1305/poly1305_ameth.c
new file mode 100644
index 0000000000..93c6bc0c33
--- /dev/null
+++ b/crypto/poly1305/poly1305_ameth.c
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2007-2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <stdio.h>
+#include "internal/cryptlib.h"
+#include <openssl/evp.h>
+#include "internal/asn1_int.h"
+#include "internal/poly1305.h"
+#include "poly1305_local.h"
+
+/*
+ * POLY1305 "ASN1" method. This is just here to indicate the maximum
+ * POLY1305 output length and to free up a POLY1305 key.
+ */
+
+static int poly1305_size(const EVP_PKEY *pkey)
+{
+    return POLY1305_DIGEST_SIZE;
+}
+
+static void poly1305_key_free(EVP_PKEY *pkey)
+{
+    ASN1_OCTET_STRING *os = EVP_PKEY_get0(pkey);
+    if (os != NULL) {
+        if (os->data != NULL)
+            OPENSSL_cleanse(os->data, os->length);
+        ASN1_OCTET_STRING_free(os);
+    }
+}
+
+static int poly1305_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
+{
+    /* nothing, (including ASN1_PKEY_CTRL_DEFAULT_MD_NID), is supported */
+    return -2;
+}
+
+static int poly1305_pkey_public_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
+{
+    return ASN1_OCTET_STRING_cmp(EVP_PKEY_get0(a), EVP_PKEY_get0(b));
+}
+
+const EVP_PKEY_ASN1_METHOD poly1305_asn1_meth = {
+    EVP_PKEY_POLY1305,
+    EVP_PKEY_POLY1305,
+    0,
+
+    "POLY1305",
+    "OpenSSL POLY1305 method",
+
+    0, 0, poly1305_pkey_public_cmp, 0,
+
+    0, 0, 0,
+
+    poly1305_size,
+    0, 0,
+    0, 0, 0, 0, 0, 0, 0,
+
+    poly1305_key_free,
+    poly1305_pkey_ctrl,
+    0, 0
+};
diff --git a/crypto/poly1305/poly1305_pmeth.c b/crypto/poly1305/poly1305_pmeth.c
new file mode 100644
index 0000000000..7bc6add681
--- /dev/null
+++ b/crypto/poly1305/poly1305_pmeth.c
@@ -0,0 +1,192 @@
+/*
+ * Copyright 2007-2017 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <stdio.h>
+#include "internal/cryptlib.h"
+#include <openssl/x509.h>
+#include <openssl/x509v3.h>
+#include <openssl/evp.h>
+#include "internal/poly1305.h"
+#include "poly1305_local.h"
+#include "internal/evp_int.h"
+
+/* POLY1305 pkey context structure */
+
+typedef struct {
+    ASN1_OCTET_STRING ktmp;     /* Temp storage for key */
+    POLY1305 ctx;
+} POLY1305_PKEY_CTX;
+
+static int pkey_poly1305_init(EVP_PKEY_CTX *ctx)
+{
+    POLY1305_PKEY_CTX *pctx;
+
+    pctx = OPENSSL_zalloc(sizeof(*pctx));
+    if (pctx == NULL)
+        return 0;
+    pctx->ktmp.type = V_ASN1_OCTET_STRING;
+
+    EVP_PKEY_CTX_set_data(ctx, pctx);
+    EVP_PKEY_CTX_set0_keygen_info(ctx, NULL, 0);
+    return 1;
+}
+
+static void pkey_poly1305_cleanup(EVP_PKEY_CTX *ctx)
+{
+    POLY1305_PKEY_CTX *pctx = EVP_PKEY_CTX_get_data(ctx);
+
+    if (pctx != NULL) {
+        OPENSSL_clear_free(pctx->ktmp.data, pctx->ktmp.length);
+        OPENSSL_clear_free(pctx, sizeof(*pctx));
+        EVP_PKEY_CTX_set_data(ctx, NULL);
+    }
+}
+
+static int pkey_poly1305_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
+{
+    POLY1305_PKEY_CTX *sctx, *dctx;
+
+    /* allocate memory for dst->data and a new POLY1305_CTX in dst->data->ctx */
+    if (!pkey_poly1305_init(dst))
+        return 0;
+    sctx = EVP_PKEY_CTX_get_data(src);
+    dctx = EVP_PKEY_CTX_get_data(dst);
+    if (ASN1_STRING_get0_data(&sctx->ktmp) != NULL &&
+        !ASN1_STRING_copy(&dctx->ktmp, &sctx->ktmp)) {
+        /* cleanup and free the POLY1305_PKEY_CTX in dst->data */
+        pkey_poly1305_cleanup(dst);
+        return 0;
+    }
+    memcpy(&dctx->ctx, &sctx->ctx, sizeof(POLY1305));
+    return 1;
+}
+
+static int pkey_poly1305_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
+{
+    ASN1_OCTET_STRING *key;
+    POLY1305_PKEY_CTX *pctx = EVP_PKEY_CTX_get_data(ctx);
+
+    if (ASN1_STRING_get0_data(&pctx->ktmp) == NULL)
+        return 0;
+    key = ASN1_OCTET_STRING_dup(&pctx->ktmp);
+    if (key == NULL)
+        return 0;
+    return EVP_PKEY_assign_POLY1305(pkey, key);
+}
+
+static int int_update(EVP_MD_CTX *ctx, const void *data, size_t count)
+{
+    POLY1305_PKEY_CTX *pctx = EVP_PKEY_CTX_get_data(EVP_MD_CTX_pkey_ctx(ctx));
+
+    Poly1305_Update(&pctx->ctx, data, count);
+    return 1;
+}
+
+static int poly1305_signctx_init(EVP_PKEY_CTX *ctx, EVP_MD_CTX *mctx)
+{
+    POLY1305_PKEY_CTX *pctx = ctx->data;
+    ASN1_OCTET_STRING *key = (ASN1_OCTET_STRING *)ctx->pkey->pkey.ptr;
+
+    if (key->length != POLY1305_KEY_SIZE)
+        return 0;
+    EVP_MD_CTX_set_flags(mctx, EVP_MD_CTX_FLAG_NO_INIT);
+    EVP_MD_CTX_set_update_fn(mctx, int_update);
+    Poly1305_Init(&pctx->ctx, key->data);
+    return 1;
+}
+static int poly1305_signctx(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen,
+                            EVP_MD_CTX *mctx)
+{
+    POLY1305_PKEY_CTX *pctx = ctx->data;
+
+    *siglen = POLY1305_DIGEST_SIZE;
+    if (sig != NULL)
+        Poly1305_Final(&pctx->ctx, sig);
+    return 1;
+}
+
+static int pkey_poly1305_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
+{
+    POLY1305_PKEY_CTX *pctx = EVP_PKEY_CTX_get_data(ctx);
+    const unsigned char *key;
+    size_t len;
+
+    switch (type) {
+
+    case EVP_PKEY_CTRL_MD:
+        /* ignore */
+        break;
+
+    case EVP_PKEY_CTRL_SET_MAC_KEY:
+    case EVP_PKEY_CTRL_DIGESTINIT:
+        if (type == EVP_PKEY_CTRL_SET_MAC_KEY) {
+            /* user explicitly setting the key */
+            key = p2;
+            len = p1;
+        } else {
+            /* user indirectly setting the key via EVP_DigestSignInit */
+            key = EVP_PKEY_get0_poly1305(EVP_PKEY_CTX_get0_pkey(ctx), &len);
+        }
+        if (key == NULL || len != POLY1305_KEY_SIZE ||
+            !ASN1_OCTET_STRING_set(&pctx->ktmp, key, len))
+            return 0;
+        Poly1305_Init(&pctx->ctx, ASN1_STRING_get0_data(&pctx->ktmp));
+        break;
+
+    default:
+        return -2;
+
+    }
+    return 1;
+}
+
+static int pkey_poly1305_ctrl_str(EVP_PKEY_CTX *ctx,
+                                  const char *type, const char *value)
+{
+    if (value == NULL)
+        return 0;
+    if (strcmp(type, "key") == 0)
+        return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_SET_MAC_KEY, value);
+    if (strcmp(type, "hexkey") == 0)
+        return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_SET_MAC_KEY, value);
+    return -2;
+}
+
+const EVP_PKEY_METHOD poly1305_pkey_meth = {
+    EVP_PKEY_POLY1305,
+    EVP_PKEY_FLAG_SIGCTX_CUSTOM, /* we don't deal with a separate MD */
+    pkey_poly1305_init,
+    pkey_poly1305_copy,
+    pkey_poly1305_cleanup,
+
+    0, 0,
+
+    0,
+    pkey_poly1305_keygen,
+
+    0, 0,
+
+    0, 0,
+
+    0, 0,
+
+    poly1305_signctx_init,
+    poly1305_signctx,
+
+    0, 0,
+
+    0, 0,
+
+    0, 0,
+
+    0, 0,
+
+    pkey_poly1305_ctrl,
+    pkey_poly1305_ctrl_str
+};