Adding base utils for JWT service account workflow. OpenSSL base64 decoding is

a disaster and does not support url_safe which we need for the JWT.
	Change on 2014/12/12 by jboeuf <jboeuf@google.com>
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=82020601

4 files changed, 458 insertions, 0 deletions

diff --git a/src/core/security/base64.c b/src/core/security/base64.c
new file mode 100644
index 0000000000..f6c3c52327
--- /dev/null
+++ b/src/core/security/base64.c
@@ -0,0 +1,197 @@
+/*
+ *
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/security/base64.h"
+
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/useful.h>
+
+/* --- Constants. --- */
+
+static const char base64_bytes[] = {
+    -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,
+    -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,
+    -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,
+    -1,   -1,   -1,   -1,   -1,   -1,   -1,   0x3E, -1,   -1,   -1,   0x3F,
+    0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, -1,   -1,
+    -1,   0x7F, -1,   -1,   -1,   0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
+    0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12,
+    0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, -1,   -1,   -1,   -1,   -1,
+    -1,   0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24,
+    0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30,
+    0x31, 0x32, 0x33, -1,   -1,   -1,   -1,   -1};
+
+static const char base64_url_unsafe_chars[] =
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+static const char base64_url_safe_chars[] =
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
+
+#define GRPC_BASE64_PAD_CHAR '='
+#define GRPC_BASE64_PAD_BYTE 0x7F
+#define GRPC_BASE64_MULTILINE_LINE_LEN 76
+#define GRPC_BASE64_MULTILINE_NUM_BLOCKS (GRPC_BASE64_MULTILINE_LINE_LEN / 4)
+
+/* --- base64 functions. --- */
+
+char *grpc_base64_encode(const void *vdata, size_t data_size, int url_safe,
+                         int multiline) {
+  const unsigned char *data = vdata;
+  const char *base64_chars =
+      url_safe ? base64_url_safe_chars : base64_url_unsafe_chars;
+  size_t result_projected_size =
+      4 * ((data_size + 3) / 3) +
+      2 * (multiline ? (data_size / (3 * GRPC_BASE64_MULTILINE_NUM_BLOCKS))
+                     : 0) +
+      1;
+  char *result = gpr_malloc(result_projected_size);
+  char *current = result;
+  size_t num_blocks = 0;
+  size_t i = 0;
+
+  /* Encode each block. */
+  while (data_size >= 3) {
+    *current++ = base64_chars[(data[i] >> 2) & 0x3F];
+    *current++ =
+        base64_chars[((data[i] & 0x03) << 4) | ((data[i + 1] >> 4) & 0x0F)];
+    *current++ =
+        base64_chars[((data[i + 1] & 0x0F) << 2) | ((data[i + 2] >> 6) & 0x03)];
+    *current++ = base64_chars[data[i + 2] & 0x3F];
+
+    data_size -= 3;
+    i += 3;
+    if (multiline && (++num_blocks == GRPC_BASE64_MULTILINE_NUM_BLOCKS)) {
+      *current++ = '\r';
+      *current++ = '\n';
+      num_blocks = 0;
+    }
+  }
+
+  /* Take care of the tail. */
+  if (data_size == 2) {
+    *current++ = base64_chars[(data[i] >> 2) & 0x3F];
+    *current++ =
+        base64_chars[((data[i] & 0x03) << 4) | ((data[i + 1] >> 4) & 0x0F)];
+    *current++ = base64_chars[(data[i + 1] & 0x0F) << 2];
+    *current++ = GRPC_BASE64_PAD_CHAR;
+  } else if (data_size == 1) {
+    *current++ = base64_chars[(data[i] >> 2) & 0x3F];
+    *current++ = base64_chars[(data[i] & 0x03) << 4];
+    *current++ = GRPC_BASE64_PAD_CHAR;
+    *current++ = GRPC_BASE64_PAD_CHAR;
+  }
+
+  GPR_ASSERT((current - result) < result_projected_size);
+  result[current - result] = '\0';
+  return result;
+}
+
+gpr_slice grpc_base64_decode(const char *b64, int url_safe) {
+  size_t b64_len = strlen(b64);
+  gpr_slice result = gpr_slice_malloc(b64_len);
+  unsigned char *current = GPR_SLICE_START_PTR(result);
+  size_t result_size = 0;
+  unsigned char codes[4];
+  size_t num_codes = 0;
+
+  while (b64_len--) {
+    unsigned char c = *b64++;
+    signed char code;
+    if (c >= GPR_ARRAY_SIZE(base64_bytes)) continue;
+    if (url_safe) {
+      if (c == '+' || c == '/') {
+        gpr_log(GPR_ERROR, "Invalid character for url safe base64 %c", c);
+        goto fail;
+      }
+      if (c == '-') {
+        c = '+';
+      } else if (c == '_') {
+        c = '/';
+      }
+    }
+    code = base64_bytes[c];
+    if (code == -1) {
+      if (c != '\r' && c != '\n') {
+        gpr_log(GPR_ERROR, "Invalid character %c", c);
+        goto fail;
+      }
+    } else {
+      codes[num_codes++] = code;
+      if (num_codes == 4) {
+        if (codes[0] == GRPC_BASE64_PAD_BYTE ||
+            codes[1] == GRPC_BASE64_PAD_BYTE) {
+          gpr_log(GPR_ERROR, "Invalid padding detected.");
+          goto fail;
+        }
+        if (codes[2] == GRPC_BASE64_PAD_BYTE) {
+          if (codes[3] == GRPC_BASE64_PAD_BYTE) {
+            /* Double padding. */
+            gpr_uint32 packed = (codes[0] << 2) | (codes[1] >> 4);
+            current[result_size++] = (unsigned char)packed;
+          } else {
+            gpr_log(GPR_ERROR, "Invalid padding detected.");
+            goto fail;
+          }
+        } else if (codes[3] == GRPC_BASE64_PAD_BYTE) {
+          /* Single padding. */
+          gpr_uint32 packed =
+              (codes[0] << 10) | (codes[1] << 4) | (codes[2] >> 2);
+          current[result_size++] = (unsigned char)(packed >> 8);
+          current[result_size++] = (unsigned char)(packed);
+        } else {
+          /* No padding. */
+          gpr_uint32 packed =
+              (codes[0] << 18) | (codes[1] << 12) | (codes[2] << 6) | codes[3];
+          current[result_size++] = (unsigned char)(packed >> 16);
+          current[result_size++] = (unsigned char)(packed >> 8);
+          current[result_size++] = (unsigned char)(packed);
+        }
+        num_codes = 0;
+      }
+    }
+  }
+
+  if (num_codes != 0) {
+    gpr_log(GPR_ERROR, "Invalid base64.");
+    gpr_slice_unref(result);
+    return gpr_empty_slice();
+  }
+  GPR_SLICE_SET_LENGTH(result, result_size);
+  return result;
+
+fail:
+  gpr_slice_unref(result);
+  return gpr_empty_slice();
+}
diff --git a/src/core/security/base64.h b/src/core/security/base64.h
new file mode 100644
index 0000000000..7bfb89b071
--- /dev/null
+++ b/src/core/security/base64.h
@@ -0,0 +1,48 @@
+/*
+ *
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef __GRPC_INTERNAL_SECURITY_BASE64_H_
+#define __GRPC_INTERNAL_SECURITY_BASE64_H_
+
+#include <grpc/support/slice.h>
+
+/* Encodes data using base64. It is the caller's responsability to free
+   the returned char * using gpr_free. Returns NULL on NULL input. */
+char *grpc_base64_encode(const void *data, size_t data_size, int url_safe,
+                         int multiline);
+
+/* Decodes data according to the base64 specification. Returns an empty
+   slice in case of failure. */
+gpr_slice grpc_base64_decode(const char *b64, int url_safe);
+
+#endif /* __GRPC_INTERNAL_SECURITY_BASE64_H_ */
diff --git a/src/core/security/json_token.c b/src/core/security/json_token.c
new file mode 100644
index 0000000000..ba5e2cf48c
--- /dev/null
+++ b/src/core/security/json_token.c
@@ -0,0 +1,152 @@
+/*
+ *
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/security/json_token.h"
+
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string.h>
+#include <openssl/bio.h>
+#include <openssl/pem.h>
+
+#include "third_party/cJSON/cJSON.h"
+
+/* --- Constants. --- */
+
+/* 1 hour max. */
+const gpr_timespec grpc_max_service_accounts_token_validity = {3600, 0};
+
+#define GRPC_AUTH_JSON_KEY_TYPE_INVALID "invalid"
+#define GRPC_AUTH_JSON_KEY_TYPE_SERVICE_ACCOUNT "service_account"
+
+/* --- grpc_auth_json_key. --- */
+
+static const char *json_get_string_property(cJSON *json,
+                                            const char *prop_name) {
+  cJSON *child = NULL;
+  child = cJSON_GetObjectItem(json, prop_name);
+  if (child == NULL || child->type != cJSON_String) {
+    gpr_log(GPR_ERROR, "Invalid or missing %s property.", prop_name);
+    return NULL;
+  }
+  return child->valuestring;
+}
+
+static int set_json_key_string_property(cJSON *json, const char *prop_name,
+                                        char **json_key_field) {
+  const char *prop_value = json_get_string_property(json, prop_name);
+  if (prop_value == NULL) return 0;
+  *json_key_field = gpr_strdup(prop_value);
+  return 1;
+}
+
+int grpc_auth_json_key_is_valid(grpc_auth_json_key *json_key) {
+  return (json_key != NULL) &&
+         strcmp(json_key->type, GRPC_AUTH_JSON_KEY_TYPE_INVALID);
+}
+
+grpc_auth_json_key grpc_auth_json_key_create_from_string(
+    const char *json_string) {
+  grpc_auth_json_key result;
+  cJSON *json = cJSON_Parse(json_string);
+  BIO *bio = NULL;
+  const char *prop_value;
+  int success = 0;
+
+  memset(&result, 0, sizeof(grpc_auth_json_key));
+  result.type = GRPC_AUTH_JSON_KEY_TYPE_INVALID;
+  if (json == NULL) {
+    gpr_log(GPR_ERROR, "Invalid json string %s", json_string);
+    return result;
+  }
+
+  prop_value = json_get_string_property(json, "type");
+  if (prop_value == NULL ||
+      strcmp(prop_value, GRPC_AUTH_JSON_KEY_TYPE_SERVICE_ACCOUNT)) {
+    goto end;
+  }
+  result.type = GRPC_AUTH_JSON_KEY_TYPE_SERVICE_ACCOUNT;
+
+  if (!set_json_key_string_property(json, "private_key_id",
+                                    &result.private_key_id) ||
+      !set_json_key_string_property(json, "client_id", &result.client_id) ||
+      !set_json_key_string_property(json, "client_email",
+                                    &result.client_email)) {
+    goto end;
+  }
+
+  prop_value = json_get_string_property(json, "private_key");
+  if (prop_value == NULL) {
+    goto end;
+  }
+  bio = BIO_new(BIO_s_mem());
+  if (BIO_puts(bio, prop_value) != strlen(prop_value)) {
+    gpr_log(GPR_ERROR, "Could not write into openssl BIO.");
+    goto end;
+  }
+  result.private_key = PEM_read_bio_RSAPrivateKey(bio, NULL, NULL, "");
+  if (result.private_key == NULL) {
+    gpr_log(GPR_ERROR, "Could not deserialize private key.");
+    goto end;
+  }
+  success = 1;
+
+end:
+  if (bio != NULL) BIO_free(bio);
+  if (json != NULL) cJSON_Delete(json);
+  if (!success) grpc_auth_json_key_destruct(&result);
+  return result;
+}
+
+void grpc_auth_json_key_destruct(grpc_auth_json_key *json_key) {
+  if (json_key == NULL) return;
+  json_key->type = GRPC_AUTH_JSON_KEY_TYPE_INVALID;
+  if (json_key->client_id != NULL) {
+    gpr_free(json_key->client_id);
+    json_key->client_id = NULL;
+  }
+  if (json_key->private_key_id != NULL) {
+    gpr_free(json_key->private_key_id);
+    json_key->private_key_id = NULL;
+  }
+  if (json_key->client_email != NULL) {
+    gpr_free(json_key->client_email);
+    json_key->client_email = NULL;
+  }
+  if (json_key->private_key != NULL) {
+    RSA_free(json_key->private_key);
+    json_key->private_key = NULL;
+  }
+}
diff --git a/src/core/security/json_token.h b/src/core/security/json_token.h
new file mode 100644
index 0000000000..a1456ebc22
--- /dev/null
+++ b/src/core/security/json_token.h
@@ -0,0 +1,61 @@
+/*
+ *
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef __GRPC_INTERNAL_SECURITY_JSON_TOKEN_H_
+#define __GRPC_INTERNAL_SECURITY_JSON_TOKEN_H_
+
+#include <grpc/support/slice.h>
+#include <openssl/rsa.h>
+
+/* --- json_key parsing. Exposed for testing only. --- */
+
+typedef struct {
+  char *type;
+  char *private_key_id;
+  char *client_id;
+  char *client_email;
+  RSA *private_key;
+} grpc_auth_json_key;
+
+/* Returns 1 if the object is valid, 0 otherwise. */
+int grpc_auth_json_key_is_valid(grpc_auth_json_key *json_key);
+
+/* Creates a json_key object from string. Returns an invalid object if a parsing
+   error has been encountered. */
+grpc_auth_json_key grpc_auth_json_key_create_from_string(
+    const char *json_string);
+
+/* Destructs the object. */
+void grpc_auth_json_key_destruct(grpc_auth_json_key *json_key);
+
+#endif /* __GRPC_INTERNAL_SECURITY_JSON_TOKEN_H_ */