| #include <stdio.h> |
| #include <stdlib.h> |
| #include <netinet/in.h> |
| #include <unistd.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <string.h> |
| |
| #define ElfHeaderSize (64 * 1024) |
| #define ElfPages (ElfHeaderSize / 4096) |
| #define KERNELBASE (0xc000000000000000) |
| |
| void get4k(FILE *file, char *buf ) |
| { |
| unsigned j; |
| unsigned num = fread(buf, 1, 4096, file); |
| for ( j=num; j<4096; ++j ) |
| buf[j] = 0; |
| } |
| |
| void put4k(FILE *file, char *buf ) |
| { |
| fwrite(buf, 1, 4096, file); |
| } |
| |
| void death(const char *msg, FILE *fdesc, const char *fname) |
| { |
| fprintf(stderr, msg); |
| fclose(fdesc); |
| unlink(fname); |
| exit(1); |
| } |
| |
| int main(int argc, char **argv) |
| { |
| char inbuf[4096]; |
| FILE *ramDisk = NULL; |
| FILE *sysmap = NULL; |
| FILE *inputVmlinux = NULL; |
| FILE *outputVmlinux = NULL; |
| |
| unsigned i = 0; |
| unsigned long ramFileLen = 0; |
| unsigned long ramLen = 0; |
| unsigned long roundR = 0; |
| |
| unsigned long sysmapFileLen = 0; |
| unsigned long sysmapLen = 0; |
| unsigned long sysmapPages = 0; |
| char* ptr_end = NULL; |
| unsigned long offset_end = 0; |
| |
| unsigned long kernelLen = 0; |
| unsigned long actualKernelLen = 0; |
| unsigned long round = 0; |
| unsigned long roundedKernelLen = 0; |
| unsigned long ramStartOffs = 0; |
| unsigned long ramPages = 0; |
| unsigned long roundedKernelPages = 0; |
| unsigned long hvReleaseData = 0; |
| u_int32_t eyeCatcher = 0xc8a5d9c4; |
| unsigned long naca = 0; |
| unsigned long xRamDisk = 0; |
| unsigned long xRamDiskSize = 0; |
| long padPages = 0; |
| |
| |
| if (argc < 2) { |
| fprintf(stderr, "Name of RAM disk file missing.\n"); |
| exit(1); |
| } |
| |
| if (argc < 3) { |
| fprintf(stderr, "Name of System Map input file is missing.\n"); |
| exit(1); |
| } |
| |
| if (argc < 4) { |
| fprintf(stderr, "Name of vmlinux file missing.\n"); |
| exit(1); |
| } |
| |
| if (argc < 5) { |
| fprintf(stderr, "Name of vmlinux output file missing.\n"); |
| exit(1); |
| } |
| |
| |
| ramDisk = fopen(argv[1], "r"); |
| if ( ! ramDisk ) { |
| fprintf(stderr, "RAM disk file \"%s\" failed to open.\n", argv[1]); |
| exit(1); |
| } |
| |
| sysmap = fopen(argv[2], "r"); |
| if ( ! sysmap ) { |
| fprintf(stderr, "System Map file \"%s\" failed to open.\n", argv[2]); |
| exit(1); |
| } |
| |
| inputVmlinux = fopen(argv[3], "r"); |
| if ( ! inputVmlinux ) { |
| fprintf(stderr, "vmlinux file \"%s\" failed to open.\n", argv[3]); |
| exit(1); |
| } |
| |
| outputVmlinux = fopen(argv[4], "w+"); |
| if ( ! outputVmlinux ) { |
| fprintf(stderr, "output vmlinux file \"%s\" failed to open.\n", argv[4]); |
| exit(1); |
| } |
| |
| |
| |
| /* Input Vmlinux file */ |
| fseek(inputVmlinux, 0, SEEK_END); |
| kernelLen = ftell(inputVmlinux); |
| fseek(inputVmlinux, 0, SEEK_SET); |
| printf("kernel file size = %d\n", kernelLen); |
| if ( kernelLen == 0 ) { |
| fprintf(stderr, "You must have a linux kernel specified as argv[3]\n"); |
| exit(1); |
| } |
| |
| actualKernelLen = kernelLen - ElfHeaderSize; |
| |
| printf("actual kernel length (minus ELF header) = %d\n", actualKernelLen); |
| |
| round = actualKernelLen % 4096; |
| roundedKernelLen = actualKernelLen; |
| if ( round ) |
| roundedKernelLen += (4096 - round); |
| printf("Vmlinux length rounded up to a 4k multiple = %ld/0x%lx \n", roundedKernelLen, roundedKernelLen); |
| roundedKernelPages = roundedKernelLen / 4096; |
| printf("Vmlinux pages to copy = %ld/0x%lx \n", roundedKernelPages, roundedKernelPages); |
| |
| |
| |
| /* Input System Map file */ |
| /* (needs to be processed simply to determine if we need to add pad pages due to the static variables not being included in the vmlinux) */ |
| fseek(sysmap, 0, SEEK_END); |
| sysmapFileLen = ftell(sysmap); |
| fseek(sysmap, 0, SEEK_SET); |
| printf("%s file size = %ld/0x%lx \n", argv[2], sysmapFileLen, sysmapFileLen); |
| |
| sysmapLen = sysmapFileLen; |
| |
| roundR = 4096 - (sysmapLen % 4096); |
| if (roundR) { |
| printf("Rounding System Map file up to a multiple of 4096, adding %ld/0x%lx \n", roundR, roundR); |
| sysmapLen += roundR; |
| } |
| printf("Rounded System Map size is %ld/0x%lx \n", sysmapLen, sysmapLen); |
| |
| /* Process the Sysmap file to determine where _end is */ |
| sysmapPages = sysmapLen / 4096; |
| /* read the whole file line by line, expect that it doesn't fail */ |
| while ( fgets(inbuf, 4096, sysmap) ) ; |
| /* search for _end in the last page of the system map */ |
| ptr_end = strstr(inbuf, " _end"); |
| if (!ptr_end) { |
| fprintf(stderr, "Unable to find _end in the sysmap file \n"); |
| fprintf(stderr, "inbuf: \n"); |
| fprintf(stderr, "%s \n", inbuf); |
| exit(1); |
| } |
| printf("Found _end in the last page of the sysmap - backing up 10 characters it looks like %s", ptr_end-10); |
| /* convert address of _end in system map to hex offset. */ |
| offset_end = (unsigned int)strtol(ptr_end-10, NULL, 16); |
| /* calc how many pages we need to insert between the vmlinux and the start of the ram disk */ |
| padPages = offset_end/4096 - roundedKernelPages; |
| |
| /* Check and see if the vmlinux is already larger than _end in System.map */ |
| if (padPages < 0) { |
| /* vmlinux is larger than _end - adjust the offset to the start of the embedded ram disk */ |
| offset_end = roundedKernelLen; |
| printf("vmlinux is larger than _end indicates it needs to be - offset_end = %lx \n", offset_end); |
| padPages = 0; |
| printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages); |
| } |
| else { |
| /* _end is larger than vmlinux - use the offset to _end that we calculated from the system map */ |
| printf("vmlinux is smaller than _end indicates is needed - offset_end = %lx \n", offset_end); |
| printf("will insert %lx pages between the vmlinux and the start of the ram disk \n", padPages); |
| } |
| |
| |
| |
| /* Input Ram Disk file */ |
| // Set the offset that the ram disk will be started at. |
| ramStartOffs = offset_end; /* determined from the input vmlinux file and the system map */ |
| printf("Ram Disk will start at offset = 0x%lx \n", ramStartOffs); |
| |
| fseek(ramDisk, 0, SEEK_END); |
| ramFileLen = ftell(ramDisk); |
| fseek(ramDisk, 0, SEEK_SET); |
| printf("%s file size = %ld/0x%lx \n", argv[1], ramFileLen, ramFileLen); |
| |
| ramLen = ramFileLen; |
| |
| roundR = 4096 - (ramLen % 4096); |
| if ( roundR ) { |
| printf("Rounding RAM disk file up to a multiple of 4096, adding %ld/0x%lx \n", roundR, roundR); |
| ramLen += roundR; |
| } |
| |
| printf("Rounded RAM disk size is %ld/0x%lx \n", ramLen, ramLen); |
| ramPages = ramLen / 4096; |
| printf("RAM disk pages to copy = %ld/0x%lx\n", ramPages, ramPages); |
| |
| |
| |
| // Copy 64K ELF header |
| for (i=0; i<(ElfPages); ++i) { |
| get4k( inputVmlinux, inbuf ); |
| put4k( outputVmlinux, inbuf ); |
| } |
| |
| /* Copy the vmlinux (as full pages). */ |
| fseek(inputVmlinux, ElfHeaderSize, SEEK_SET); |
| for ( i=0; i<roundedKernelPages; ++i ) { |
| get4k( inputVmlinux, inbuf ); |
| put4k( outputVmlinux, inbuf ); |
| } |
| |
| /* Insert pad pages (if appropriate) that are needed between */ |
| /* | the end of the vmlinux and the ram disk. */ |
| for (i=0; i<padPages; ++i) { |
| memset(inbuf, 0, 4096); |
| put4k(outputVmlinux, inbuf); |
| } |
| |
| /* Copy the ram disk (as full pages). */ |
| for ( i=0; i<ramPages; ++i ) { |
| get4k( ramDisk, inbuf ); |
| put4k( outputVmlinux, inbuf ); |
| } |
| |
| /* Close the input files */ |
| fclose(ramDisk); |
| fclose(inputVmlinux); |
| /* And flush the written output file */ |
| fflush(outputVmlinux); |
| |
| |
| |
| /* Fixup the new vmlinux to contain the ram disk starting offset (xRamDisk) and the ram disk size (xRamDiskSize) */ |
| /* fseek to the hvReleaseData pointer */ |
| fseek(outputVmlinux, ElfHeaderSize + 0x24, SEEK_SET); |
| if (fread(&hvReleaseData, 4, 1, outputVmlinux) != 1) { |
| death("Could not read hvReleaseData pointer\n", outputVmlinux, argv[4]); |
| } |
| hvReleaseData = ntohl(hvReleaseData); /* Convert to native int */ |
| printf("hvReleaseData is at %08x\n", hvReleaseData); |
| |
| /* fseek to the hvReleaseData */ |
| fseek(outputVmlinux, ElfHeaderSize + hvReleaseData, SEEK_SET); |
| if (fread(inbuf, 0x40, 1, outputVmlinux) != 1) { |
| death("Could not read hvReleaseData\n", outputVmlinux, argv[4]); |
| } |
| /* Check hvReleaseData sanity */ |
| if (memcmp(inbuf, &eyeCatcher, 4) != 0) { |
| death("hvReleaseData is invalid\n", outputVmlinux, argv[4]); |
| } |
| /* Get the naca pointer */ |
| naca = ntohl(*((u_int32_t*) &inbuf[0x0C])) - KERNELBASE; |
| printf("Naca is at offset 0x%lx \n", naca); |
| |
| /* fseek to the naca */ |
| fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET); |
| if (fread(inbuf, 0x18, 1, outputVmlinux) != 1) { |
| death("Could not read naca\n", outputVmlinux, argv[4]); |
| } |
| xRamDisk = ntohl(*((u_int32_t *) &inbuf[0x0c])); |
| xRamDiskSize = ntohl(*((u_int32_t *) &inbuf[0x14])); |
| /* Make sure a RAM disk isn't already present */ |
| if ((xRamDisk != 0) || (xRamDiskSize != 0)) { |
| death("RAM disk is already attached to this kernel\n", outputVmlinux, argv[4]); |
| } |
| /* Fill in the values */ |
| *((u_int32_t *) &inbuf[0x0c]) = htonl(ramStartOffs); |
| *((u_int32_t *) &inbuf[0x14]) = htonl(ramPages); |
| |
| /* Write out the new naca */ |
| fflush(outputVmlinux); |
| fseek(outputVmlinux, ElfHeaderSize + naca, SEEK_SET); |
| if (fwrite(inbuf, 0x18, 1, outputVmlinux) != 1) { |
| death("Could not write naca\n", outputVmlinux, argv[4]); |
| } |
| printf("Ram Disk of 0x%lx pages is attached to the kernel at offset 0x%08x\n", |
| ramPages, ramStartOffs); |
| |
| /* Done */ |
| fclose(outputVmlinux); |
| /* Set permission to executable */ |
| chmod(argv[4], S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH); |
| |
| return 0; |
| } |
| |