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 <experimental/filesystem> 22 #include <fstream> 23 #include <sstream> 24 25 namespace google 26 { 27 namespace ipmi 28 { 29 namespace fs = std::experimental::filesystem; 30 31 struct CpldRequest 32 { 33 uint8_t subcommand; 34 uint8_t id; 35 } __attribute__((packed)); 36 37 struct CpldReply 38 { 39 uint8_t subcommand; 40 uint8_t major; 41 uint8_t minor; 42 uint8_t point; 43 uint8_t subpoint; 44 } __attribute__((packed)); 45 46 // 47 // Handle reading the cpld version from the tmpfs. 48 // 49 ipmi_ret_t CpldVersion(const uint8_t* reqBuf, uint8_t* replyBuf, 50 size_t* dataLen) 51 { 52 if ((*dataLen) < sizeof(struct CpldRequest)) 53 { 54 fprintf(stderr, "Invalid command length: %u\n", 55 static_cast<uint32_t>(*dataLen)); 56 return IPMI_CC_INVALID; 57 } 58 59 // reqBuf[0] is the subcommand. 60 // reqBuf[1] is the CPLD id. "/run/cpld{id}.version" is what we read. 61 // Verified that this cast actually returns the value 255 and not something 62 // negative in the case where reqBuf[1] is 0xff. However, it looks weird 63 // since I would expect int(uint8(0xff)) to be -1. So, just cast it 64 // unsigned. we're casting to an int width to avoid it thinking it's a 65 // letter, because it does that. 66 67 const auto request = 68 reinterpret_cast<const struct CpldRequest*>(&reqBuf[0]); 69 70 std::ostringstream opath; 71 opath << "/run/cpld" << static_cast<unsigned int>(request->id) 72 << ".version"; 73 // Check for file 74 75 std::error_code ec; 76 if (!fs::exists(opath.str(), ec)) 77 { 78 fprintf(stderr, "Path: '%s' doesn't exist.\n", opath.str().c_str()); 79 return IPMI_CC_INVALID; 80 } 81 // We're uninterested in the state of ec. 82 83 // If file exists, read. 84 std::ifstream ifs; 85 ifs.exceptions(std::ifstream::failbit); 86 std::string value; 87 try 88 { 89 ifs.open(opath.str()); 90 ifs >> value; 91 } 92 catch (std::ios_base::failure& fail) 93 { 94 return IPMI_CC_INVALID; 95 } 96 97 // If value parses as expected, return version. 98 int major = 0; 99 int minor = 0; 100 int point = 0; 101 int subpoint = 0; 102 103 int num_fields = 104 sscanf(value.c_str(), "%d.%d.%d.%d", &major, &minor, &point, &subpoint); 105 if (num_fields == 0) 106 { 107 fprintf(stderr, "Invalid version.\n"); 108 return IPMI_CC_INVALID; 109 } 110 111 // Truncate if the version is too high (documented). 112 struct CpldReply reply; 113 reply.subcommand = SysCpldVersion; 114 reply.major = static_cast<uint8_t>(major); 115 reply.minor = static_cast<uint8_t>(minor); 116 reply.point = static_cast<uint8_t>(point); 117 reply.subpoint = static_cast<uint8_t>(subpoint); 118 119 memcpy(&replyBuf[0], &reply, sizeof(struct CpldReply)); 120 (*dataLen) = sizeof(struct CpldReply); 121 122 return IPMI_CC_OK; 123 } 124 125 } // namespace ipmi 126 } // namespace google 127