int parse_elf_to_payload(const struct buffer *input, struct buffer *output, enum comp_algo algo) { Elf64_Phdr *phdr; Elf64_Ehdr ehdr; Elf64_Shdr *shdr; char *header; char *strtab; int headers; int segments = 1; int isize = 0, osize = 0; int doffset = 0; struct cbfs_payload_segment *segs = NULL; int i; int ret = 0; comp_func_ptr compress = compression_function(algo); if (!compress) return -1; if (elf_headers(input, &ehdr, &phdr, &shdr) < 0) return -1; DEBUG("start: parse_elf_to_payload\n"); headers = ehdr.e_phnum; header = input->data; strtab = &header[shdr[ehdr.e_shstrndx].sh_offset]; /* Count the number of headers - look for the .notes.pinfo * section */ for (i = 0; i < ehdr.e_shnum; i++) { char *name; if (i == ehdr.e_shstrndx) continue; if (shdr[i].sh_size == 0) continue; name = (char *)(strtab + shdr[i].sh_name); if (!strcmp(name, ".note.pinfo")) { segments++; isize += (unsigned int)shdr[i].sh_size; } } /* Now, regular headers - we only care about PT_LOAD headers, * because thats what we're actually going to load */ for (i = 0; i < headers; i++) { if (phdr[i].p_type != PT_LOAD) continue; /* Empty segments are never interesting */ if (phdr[i].p_memsz == 0) continue; isize += phdr[i].p_filesz; segments++; } /* allocate the segment header array */ segs = calloc(segments, sizeof(*segs)); if (segs == NULL) { ret = -1; goto out; } /* Allocate a block of memory to store the data in */ if (buffer_create(output, (segments * sizeof(*segs)) + isize, input->name) != 0) { ret = -1; goto out; } memset(output->data, 0, output->size); doffset = (segments * sizeof(*segs)); /* set up for output marshaling. This is a bit * tricky as we are marshaling the headers at the front, * and the data starting after the headers. We need to convert * the headers to the right format but the data * passes through unchanged. Unlike most XDR code, * we are doing these two concurrently. The doffset is * used to compute the address for the raw data, and the * outheader is used to marshal the headers. To make it simpler * for The Reader, we set up the headers in a separate array, * then marshal them all at once to the output. */ segments = 0; for (i = 0; i < ehdr.e_shnum; i++) { char *name; if (i == ehdr.e_shstrndx) continue; if (shdr[i].sh_size == 0) continue; name = (char *)(strtab + shdr[i].sh_name); if (!strcmp(name, ".note.pinfo")) { segs[segments].type = PAYLOAD_SEGMENT_PARAMS; segs[segments].load_addr = 0; segs[segments].len = (unsigned int)shdr[i].sh_size; segs[segments].offset = doffset; memcpy((unsigned long *)(output->data + doffset), &header[shdr[i].sh_offset], shdr[i].sh_size); doffset += segs[segments].len; osize += segs[segments].len; segments++; } } for (i = 0; i < headers; i++) { if (phdr[i].p_type != PT_LOAD) continue; if (phdr[i].p_memsz == 0) continue; if (phdr[i].p_filesz == 0) { segs[segments].type = PAYLOAD_SEGMENT_BSS; segs[segments].load_addr = phdr[i].p_paddr; segs[segments].mem_len = phdr[i].p_memsz; segs[segments].offset = doffset; segments++; continue; } if (phdr[i].p_flags & PF_X) segs[segments].type = PAYLOAD_SEGMENT_CODE; else segs[segments].type = PAYLOAD_SEGMENT_DATA; segs[segments].load_addr = phdr[i].p_paddr; segs[segments].mem_len = phdr[i].p_memsz; segs[segments].offset = doffset; /* If the compression failed or made the section is larger, use the original stuff */ int len; if (compress((char *)&header[phdr[i].p_offset], phdr[i].p_filesz, output->data + doffset, &len) || (unsigned int)len > phdr[i].p_filesz) { WARN("Compression failed or would make the data bigger " "- disabled.\n"); segs[segments].compression = 0; segs[segments].len = phdr[i].p_filesz; memcpy(output->data + doffset, &header[phdr[i].p_offset], phdr[i].p_filesz); } else { segs[segments].compression = algo; segs[segments].len = len; } doffset += segs[segments].len; osize += segs[segments].len; segments++; } segs[segments].type = PAYLOAD_SEGMENT_ENTRY; segs[segments++].load_addr = ehdr.e_entry; output->size = (segments * sizeof(*segs)) + osize; xdr_segs(output, segs, segments); out: if (segs) free(segs); if (shdr) free(shdr); if (phdr) free(phdr); return ret; }
/* returns size of result, or -1 if error. * Note that, with the new code, this function * works for all elf files, not just the restricted set. */ int parse_elf_to_stage(const struct buffer *input, struct buffer *output, uint32_t arch, comp_algo algo, uint32_t *location) { Elf64_Phdr *phdr; Elf64_Ehdr ehdr; char *buffer; struct buffer outheader; int headers; int i, outlen; uint32_t data_start, data_end, mem_end; comp_func_ptr compress = compression_function(algo); if (!compress) return -1; DEBUG("start: parse_elf_to_stage(location=0x%x)\n", *location); if (elf_headers(input, arch, &ehdr, &phdr, NULL) < 0) return -1; headers = ehdr.e_phnum; data_start = ~0; data_end = 0; mem_end = 0; for (i = 0; i < headers; i++) { unsigned int start, mend, rend; if (phdr[i].p_type != PT_LOAD) continue; /* Empty segments are never interesting */ if (phdr[i].p_memsz == 0) continue; /* BSS */ start = phdr[i].p_paddr; mend = start + phdr[i].p_memsz; rend = start + phdr[i].p_filesz; if (start < data_start) data_start = start; if (rend > data_end) data_end = rend; if (mend > mem_end) mem_end = mend; } if (data_start < *location) { data_start = *location; } if (data_end <= data_start) { ERROR("data ends (%08lx) before it starts (%08lx). Make sure " "the ELF file is correct and resides in ROM space.\n", (unsigned long)data_end, (unsigned long)data_start); exit(1); } /* allocate an intermediate buffer for the data */ buffer = calloc(data_end - data_start, 1); if (buffer == NULL) { ERROR("Unable to allocate memory: %m\n"); return -1; } /* Copy the file data into the buffer */ for (i = 0; i < headers; i++) { unsigned int l_start, l_offset = 0; if (phdr[i].p_type != PT_LOAD) continue; if (phdr[i].p_memsz == 0) continue; l_start = phdr[i].p_paddr; if (l_start < *location) { l_offset = *location - l_start; l_start = *location; } /* A legal ELF file can have a program header with * non-zero length but zero-length file size and a * non-zero offset which, added together, are > than * input->size (i.e. the total file size). So we need * to not even test in the case that p_filesz is zero. */ if (! phdr[i].p_filesz) continue; if (input->size < (phdr[i].p_offset + phdr[i].p_filesz)){ ERROR("Underflow copying out the segment." "File has %zu bytes left, segment end is %zu\n", input->size, (size_t)(phdr[i].p_offset + phdr[i].p_filesz)); free(buffer); return -1; } memcpy(buffer + (l_start - data_start), &input->data[phdr[i].p_offset + l_offset], phdr[i].p_filesz - l_offset); } /* Now make the output buffer */ if (buffer_create(output, sizeof(struct cbfs_stage) + data_end - data_start, input->name) != 0) { ERROR("Unable to allocate memory: %m\n"); free(buffer); return -1; } memset(output->data, 0, output->size); /* Compress the data, at which point we'll know information * to fill out the header. This seems backward but it works because * - the output header is a known size (not always true in many xdr's) * - we do need to know the compressed output size first * If compression fails or makes the data bigger, we'll warn about it * and use the original data. */ if (compress(buffer, data_end - data_start, (output->data + sizeof(struct cbfs_stage)), &outlen) < 0 || outlen > data_end - data_start) { WARN("Compression failed or would make the data bigger " "- disabled.\n"); memcpy(output->data + sizeof(struct cbfs_stage), buffer, data_end - data_start); algo = CBFS_COMPRESS_NONE; } free(buffer); /* Set up for output marshaling. */ outheader.data = output->data; outheader.size = 0; /* N.B. The original plan was that SELF data was B.E. * but: this is all L.E. * Maybe we should just change the spec. */ xdr_le.put32(&outheader, algo); xdr_le.put64(&outheader, ehdr.e_entry); xdr_le.put64(&outheader, data_start); xdr_le.put32(&outheader, outlen); xdr_le.put32(&outheader, mem_end - data_start); if (*location) *location -= sizeof(struct cbfs_stage); output->size = sizeof(struct cbfs_stage) + outlen; return 0; }