Fix the types used in token counts.

The number of tokens is inconsistent throughout the API. max_batchsize
is a uint16_t. max_issuance is a size_t. out_tokens_issued is a
uint8_t*. The serialization only supports up to uint16_t.

Standardize on size_t. The natural size for a count of elements is
size_t. Protocol limitations can be handled within the implementation.
Additionally, it is best not to use small types for counters in public
APIs in C/C++ because the language has implicit truncating conversions.
(Whereas code points or other enum-like values are fine because the
caller won't managed to get a 32-bit cipher suite.)

Update-Note: Fix callers of TRUST_TOKEN_ISSUER_issue to use size_t
instead of uint8_t. The max_batchsize changes should go through without
changes to the caller.

Change-Id: I9be5dd8f61abdbe5a1dbe70b8dc72d06114b1022
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/41044
Commit-Queue: Steven Valdez <svaldez@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
diff --git a/crypto/trust_token/trust_token_test.cc b/crypto/trust_token/trust_token_test.cc
index ce832db..2da8b08 100644
--- a/crypto/trust_token/trust_token_test.cc
+++ b/crypto/trust_token/trust_token_test.cc
@@ -110,7 +110,7 @@
   size_t msg_len, resp_len;
 
   size_t key_index;
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(
       TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg, &msg_len, 1));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
@@ -152,7 +152,7 @@
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
   msg_len = 10;
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_FALSE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       /*public_metadata=*/KeyID(0), /*private_metadata=*/0,
@@ -168,7 +168,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg,
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       /*public_metadata=*/KeyID(0), /*private_metadata=*/0,
@@ -190,7 +190,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &request,
                                                 &request_len, 10));
   bssl::UniquePtr<uint8_t> free_request(request);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(issuer.get(), &response, &response_len,
                                        &tokens_issued, request, request_len,
                                        /*public_metadata=*/KeyID(0),
@@ -214,7 +214,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg,
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       /*public_metadata=*/KeyID(0), /*private_metadata=*/0,
@@ -255,7 +255,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg,
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       /*public_metadata=*/KeyID(0), /*private_metadata=*/0,
@@ -349,7 +349,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg,
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       /*public_metadata=*/42, /*private_metadata=*/0, /*max_issuance=*/10));
@@ -372,7 +372,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg,
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       std::get<0>(GetParam()), std::get<1>(GetParam()), /*max_issuance=*/1));
@@ -446,7 +446,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg,
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       std::get<0>(GetParam()), std::get<1>(GetParam()), /*max_issuance=*/1));
@@ -469,7 +469,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg,
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       std::get<0>(GetParam()), std::get<1>(GetParam()), /*max_issuance=*/1));
@@ -524,7 +524,7 @@
   ASSERT_TRUE(TRUST_TOKEN_CLIENT_begin_issuance(client.get(), &issue_msg,
                                                 &msg_len, 10));
   bssl::UniquePtr<uint8_t> free_issue_msg(issue_msg);
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       std::get<0>(GetParam()), std::get<1>(GetParam()), /*max_issuance=*/1));
@@ -602,7 +602,7 @@
   // Corrupt private key scalar.
   scalars[corrupted_key]->bytes[0] ^= 42;
 
-  uint8_t tokens_issued;
+  size_t tokens_issued;
   ASSERT_TRUE(TRUST_TOKEN_ISSUER_issue(
       issuer.get(), &issue_resp, &resp_len, &tokens_issued, issue_msg, msg_len,
       /*public_metadata=*/7, std::get<0>(GetParam()), /*max_issuance=*/1));