xref: /openbmc/libcper/generator/cper-generate.c (revision e42fb487)
1 /**
2  * Describes functions for generating pseudo-random specification compliant CPER records.
3  *
4  * Author: Lawrence.Tang@arm.com
5  **/
6 
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <libcper/Cper.h>
11 #include <libcper/generator/gen-utils.h>
12 #include <libcper/generator/sections/gen-section.h>
13 #include <libcper/generator/cper-generate.h>
14 
15 EFI_ERROR_SECTION_DESCRIPTOR *generate_section_descriptor(char *type,
16 							  const size_t *lengths,
17 							  int index,
18 							  int num_sections);
19 size_t generate_section(void **location, char *type);
20 
21 //Generates a CPER record with the given section types, outputting to the given stream.
generate_cper_record(char ** types,UINT16 num_sections,FILE * out)22 void generate_cper_record(char **types, UINT16 num_sections, FILE *out)
23 {
24 	//Initialise randomiser.
25 	init_random();
26 
27 	//Generate the sections.
28 	void *sections[num_sections];
29 	size_t section_lengths[num_sections];
30 	for (int i = 0; i < num_sections; i++) {
31 		section_lengths[i] = generate_section(sections + i, types[i]);
32 		if (section_lengths[i] == 0) {
33 			//Error encountered, exit.
34 			printf("Error encountered generating section %d of type '%s', length returned zero.\n",
35 			       i + 1, types[i]);
36 			return;
37 		}
38 	}
39 
40 	//Generate the header given the number of sections.
41 	EFI_COMMON_ERROR_RECORD_HEADER *header =
42 		(EFI_COMMON_ERROR_RECORD_HEADER *)calloc(
43 			1, sizeof(EFI_COMMON_ERROR_RECORD_HEADER));
44 	header->SignatureStart = 0x52455043; //CPER
45 	header->SectionCount = num_sections;
46 	header->SignatureEnd = 0xFFFFFFFF;
47 	header->Flags = 4; //HW_ERROR_FLAGS_SIMULATED
48 	header->RecordID = (UINT64)rand();
49 	header->ErrorSeverity = rand() % 4;
50 
51 	//Generate a valid timestamp.
52 	header->TimeStamp.Century = int_to_bcd(rand() % 100);
53 	header->TimeStamp.Year = int_to_bcd(rand() % 100);
54 	header->TimeStamp.Month = int_to_bcd(rand() % 12 + 1);
55 	header->TimeStamp.Day = int_to_bcd(rand() % 31 + 1);
56 	header->TimeStamp.Hours = int_to_bcd(rand() % 24 + 1);
57 	header->TimeStamp.Seconds = int_to_bcd(rand() % 60);
58 
59 	//Turn all validation bits on.
60 	header->ValidationBits = 0x3;
61 
62 	//Generate the section descriptors given the number of sections.
63 	EFI_ERROR_SECTION_DESCRIPTOR *section_descriptors[num_sections];
64 	for (int i = 0; i < num_sections; i++) {
65 		section_descriptors[i] = generate_section_descriptor(
66 			types[i], section_lengths, i, num_sections);
67 	}
68 
69 	//Calculate total length of structure, set in header.
70 	size_t total_len = sizeof(EFI_COMMON_ERROR_RECORD_HEADER);
71 	for (int i = 0; i < num_sections; i++) {
72 		total_len += section_lengths[i];
73 	}
74 	total_len += num_sections * sizeof(EFI_ERROR_SECTION_DESCRIPTOR);
75 	header->RecordLength = (UINT32)total_len;
76 
77 	//Write to stream in order, free all resources.
78 	fwrite(header, sizeof(EFI_COMMON_ERROR_RECORD_HEADER), 1, out);
79 	fflush(out);
80 	free(header);
81 	for (int i = 0; i < num_sections; i++) {
82 		fwrite(section_descriptors[i],
83 		       sizeof(EFI_ERROR_SECTION_DESCRIPTOR), 1, out);
84 		fflush(out);
85 		free(section_descriptors[i]);
86 	}
87 	for (int i = 0; i < num_sections; i++) {
88 		fwrite(sections[i], section_lengths[i], 1, out);
89 		fflush(out);
90 		free(sections[i]);
91 	}
92 }
93 
94 //Generates a single section record for the given section, and outputs to file.
generate_single_section_record(char * type,FILE * out)95 void generate_single_section_record(char *type, FILE *out)
96 {
97 	//Generate a section.
98 	void *section = NULL;
99 	size_t section_len = generate_section(&section, type);
100 
101 	//Generate a descriptor, correct the offset.
102 	EFI_ERROR_SECTION_DESCRIPTOR *section_descriptor =
103 		generate_section_descriptor(type, &section_len, 0, 1);
104 	section_descriptor->SectionOffset =
105 		sizeof(EFI_ERROR_SECTION_DESCRIPTOR);
106 
107 	//Write all to file.
108 	fwrite(section_descriptor, sizeof(EFI_ERROR_SECTION_DESCRIPTOR), 1,
109 	       out);
110 	fwrite(section, section_len, 1, out);
111 	fflush(out);
112 
113 	//Free remaining resources.
114 	free(section_descriptor);
115 	free(section);
116 }
117 
118 //Generates a single section descriptor for a section with the given properties.
generate_section_descriptor(char * type,const size_t * lengths,int index,int num_sections)119 EFI_ERROR_SECTION_DESCRIPTOR *generate_section_descriptor(char *type,
120 							  const size_t *lengths,
121 							  int index,
122 							  int num_sections)
123 {
124 	EFI_ERROR_SECTION_DESCRIPTOR *descriptor =
125 		(EFI_ERROR_SECTION_DESCRIPTOR *)generate_random_bytes(
126 			sizeof(EFI_ERROR_SECTION_DESCRIPTOR));
127 
128 	//Set reserved bits to zero.
129 	descriptor->Resv1 = 0;
130 	descriptor->SectionFlags &= 0xFF;
131 
132 	//Validation bits all set to 'on'.
133 	descriptor->SecValidMask = 0x3;
134 
135 	//Set severity.
136 	descriptor->Severity = rand() % 4;
137 
138 	//Set length, offset from base record.
139 	descriptor->SectionLength = (UINT32)lengths[index];
140 	descriptor->SectionOffset =
141 		sizeof(EFI_COMMON_ERROR_RECORD_HEADER) +
142 		(num_sections * sizeof(EFI_ERROR_SECTION_DESCRIPTOR));
143 	for (int i = 0; i < index; i++) {
144 		descriptor->SectionOffset += lengths[i];
145 	}
146 
147 	//Ensure the FRU text is not null terminated early.
148 	for (int i = 0; i < 20; i++) {
149 		if (descriptor->FruString[i] == 0x0) {
150 			descriptor->FruString[i] = rand() % 127 + 1;
151 		}
152 
153 		//Null terminate last byte.
154 		if (i == 19) {
155 			descriptor->FruString[i] = 0x0;
156 		}
157 	}
158 
159 	//If section type is not "unknown", set section type GUID based on type name.
160 	int section_guid_found = 0;
161 	if (strcmp(type, "unknown") == 0) {
162 		section_guid_found = 1;
163 	} else {
164 		//Find the appropriate GUID for this section name.
165 		for (size_t i = 0; i < generator_definitions_len; i++) {
166 			if (strcmp(type, generator_definitions[i].ShortName) ==
167 			    0) {
168 				memcpy(&descriptor->SectionType,
169 				       generator_definitions[i].Guid,
170 				       sizeof(EFI_GUID));
171 				section_guid_found = 1;
172 				break;
173 			}
174 		}
175 	}
176 
177 	//Undefined section, show error.
178 	if (!section_guid_found) {
179 		//Undefined section, show error.
180 		printf("Undefined section type '%s' provided. See 'cper-generate --help' for command information.\n",
181 		       type);
182 		return 0;
183 	}
184 
185 	return descriptor;
186 }
187 
188 //Generates a single CPER section given the string type.
generate_section(void ** location,char * type)189 size_t generate_section(void **location, char *type)
190 {
191 	//The length of the section.
192 	size_t length = 0;
193 
194 	//If the section name is "unknown", simply generate a random bytes section.
195 	int section_generated = 0;
196 	if (strcmp(type, "unknown") == 0) {
197 		length = generate_random_section(location, rand() % 256);
198 		section_generated = 1;
199 	} else {
200 		//Function defined section, switch on the type, generate accordingly.
201 		for (size_t i = 0; i < generator_definitions_len; i++) {
202 			if (strcmp(type, generator_definitions[i].ShortName) ==
203 			    0) {
204 				length = generator_definitions[i].Generate(
205 					location);
206 				section_generated = 1;
207 				break;
208 			}
209 		}
210 	}
211 
212 	//If we didn't find a section generator for the given name, error out.
213 	if (!section_generated) {
214 		printf("Undefined section type '%s' given to generate. See 'cper-generate --help' for command information.\n",
215 		       type);
216 		return 0;
217 	}
218 
219 	return length;
220 }
221