1 /* 2 * Copyright 2018 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "cpld.hpp" 18 19 #include "main.hpp" 20 21 #include <cstring> 22 #include <experimental/filesystem> 23 #include <fstream> 24 #include <sstream> 25 26 namespace google 27 { 28 namespace ipmi 29 { 30 namespace fs = std::experimental::filesystem; 31 32 struct CpldRequest 33 { 34 uint8_t subcommand; 35 uint8_t id; 36 } __attribute__((packed)); 37 38 struct CpldReply 39 { 40 uint8_t subcommand; 41 uint8_t major; 42 uint8_t minor; 43 uint8_t point; 44 uint8_t subpoint; 45 } __attribute__((packed)); 46 47 // 48 // Handle reading the cpld version from the tmpfs. 49 // 50 ipmi_ret_t CpldVersion(const uint8_t* reqBuf, uint8_t* replyBuf, 51 size_t* dataLen) 52 { 53 if ((*dataLen) < sizeof(struct CpldRequest)) 54 { 55 std::fprintf(stderr, "Invalid command length: %u\n", 56 static_cast<uint32_t>(*dataLen)); 57 return IPMI_CC_INVALID; 58 } 59 60 // reqBuf[0] is the subcommand. 61 // reqBuf[1] is the CPLD id. "/run/cpld{id}.version" is what we read. 62 // Verified that this cast actually returns the value 255 and not something 63 // negative in the case where reqBuf[1] is 0xff. However, it looks weird 64 // since I would expect int(uint8(0xff)) to be -1. So, just cast it 65 // unsigned. we're casting to an int width to avoid it thinking it's a 66 // letter, because it does that. 67 68 const auto request = 69 reinterpret_cast<const struct CpldRequest*>(&reqBuf[0]); 70 71 std::ostringstream opath; 72 opath << "/run/cpld" << static_cast<unsigned int>(request->id) 73 << ".version"; 74 // Check for file 75 76 std::error_code ec; 77 if (!fs::exists(opath.str(), ec)) 78 { 79 std::fprintf(stderr, "Path: '%s' doesn't exist.\n", 80 opath.str().c_str()); 81 return IPMI_CC_INVALID; 82 } 83 // We're uninterested in the state of ec. 84 85 // If file exists, read. 86 std::ifstream ifs; 87 ifs.exceptions(std::ifstream::failbit); 88 std::string value; 89 try 90 { 91 ifs.open(opath.str()); 92 ifs >> value; 93 } 94 catch (std::ios_base::failure& fail) 95 { 96 return IPMI_CC_INVALID; 97 } 98 99 // If value parses as expected, return version. 100 int major = 0; 101 int minor = 0; 102 int point = 0; 103 int subpoint = 0; 104 105 int num_fields = 106 sscanf(value.c_str(), "%d.%d.%d.%d", &major, &minor, &point, &subpoint); 107 if (num_fields == 0) 108 { 109 std::fprintf(stderr, "Invalid version.\n"); 110 return IPMI_CC_INVALID; 111 } 112 113 // Truncate if the version is too high (documented). 114 struct CpldReply reply; 115 reply.subcommand = SysCpldVersion; 116 reply.major = static_cast<uint8_t>(major); 117 reply.minor = static_cast<uint8_t>(minor); 118 reply.point = static_cast<uint8_t>(point); 119 reply.subpoint = static_cast<uint8_t>(subpoint); 120 121 std::memcpy(&replyBuf[0], &reply, sizeof(struct CpldReply)); 122 (*dataLen) = sizeof(struct CpldReply); 123 124 return IPMI_CC_OK; 125 } 126 127 } // namespace ipmi 128 } // namespace google 129