1 //
2 //
3 // Copyright 2018 gRPC authors.
4 //
5 // Licensed under the Apache License, Version 2.0 (the "License");
6 // you may not use this file except in compliance with the License.
7 // You may obtain a copy of the License at
8 //
9 // http://www.apache.org/licenses/LICENSE-2.0
10 //
11 // Unless required by applicable law or agreed to in writing, software
12 // distributed under the License is distributed on an "AS IS" BASIS,
13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 // See the License for the specific language governing permissions and
15 // limitations under the License.
16 //
17 //
18
19 #include "src/core/lib/security/credentials/alts/check_gcp_environment.h"
20
21 #include <ctype.h>
22 #include <grpc/support/alloc.h>
23 #include <grpc/support/port_platform.h>
24 #include <stdio.h>
25 #include <string.h>
26
27 #include "absl/log/log.h"
28
29 const size_t kBiosDataBufferSize = 256;
30
trim(const char * src)31 static char* trim(const char* src) {
32 if (src == nullptr || *src == '\0') {
33 return nullptr;
34 }
35 char* des = nullptr;
36 size_t start = 0, end = strlen(src) - 1;
37 // find the last character that is not a whitespace.
38 while (end != 0 && isspace(src[end])) {
39 end--;
40 }
41 // find the first character that is not a whitespace.
42 while (start < strlen(src) && isspace(src[start])) {
43 start++;
44 }
45 if (start <= end) {
46 des = static_cast<char*>(
47 gpr_zalloc(sizeof(char) * (end - start + 2 /* '\0' */)));
48 memcpy(des, src + start, end - start + 1);
49 }
50 return des;
51 }
52
53 namespace grpc_core {
54 namespace internal {
55
read_bios_file(const char * bios_file)56 char* read_bios_file(const char* bios_file) {
57 FILE* fp = fopen(bios_file, "r");
58 if (!fp) {
59 VLOG(2) << "BIOS data file does not exist or cannot be opened.";
60 return nullptr;
61 }
62 char buf[kBiosDataBufferSize + 1];
63 size_t ret = fread(buf, sizeof(char), kBiosDataBufferSize, fp);
64 buf[ret] = '\0';
65 char* trimmed_buf = trim(buf);
66 fclose(fp);
67 return trimmed_buf;
68 }
69
70 } // namespace internal
71 } // namespace grpc_core
72