From 248e9bb408985a7591dd97f6c0eea1e1d936379a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timo=20Ter=C3=A4s?= Date: Sat, 1 Nov 2014 17:09:13 +0200 Subject: abuild-tar: write checksum to extended header --- abuild-tar.c | 199 ++++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 156 insertions(+), 43 deletions(-) diff --git a/abuild-tar.c b/abuild-tar.c index 4a88882..2f29d30 100644 --- a/abuild-tar.c +++ b/abuild-tar.c @@ -1,6 +1,6 @@ /* abuild-tar.c - A TAR mangling utility for .APK packages * - * Copyright (C) 2009 Timo Teräs + * Copyright (C) 2009-2014 Timo Teräs * All rights reserved. * * This program is free software; you can redistribute it and/or modify it @@ -89,6 +89,19 @@ static void put_octal(char *s, size_t l, size_t value) *(ptr--) = '0'; } +static void tarhdr_checksum(struct tar_header *hdr) +{ + const unsigned char *src; + size_t chksum, i; + + /* Recalculate checksum */ + memset(hdr->chksum, ' ', sizeof(hdr->chksum)); + src = (const unsigned char *) hdr; + for (i = chksum = 0; i < sizeof(*hdr); i++) + chksum += src[i]; + put_octal(hdr->chksum, sizeof(hdr->chksum)-1, chksum); +} + static int usage(void) { fprintf(stderr, @@ -120,7 +133,7 @@ static ssize_t full_read(int fd, void *buf, size_t count) } while (1); if (total == 0 && n < 0) - return -1; + return -errno; return total; } @@ -142,7 +155,7 @@ static ssize_t full_write(int fd, const void *buf, size_t count) } while (1); if (total == 0 && n < 0) - return -1; + return -errno; return total; } @@ -163,82 +176,182 @@ static ssize_t full_splice(int from_fd, int to_fd, size_t count) } while (1); if (total == 0 && n < 0) - return -1; + return -errno; return total; } -static int do_it(const EVP_MD *md, int cut) +#define BUF_INITIALIZER {0} +struct buf { + char *ptr; + size_t size; + size_t alloc; +}; + +static void buf_free(struct buf *b) +{ + free(b->ptr); +} + +static int buf_resize(struct buf *b, size_t newsize) { - struct tar_header hdr; - size_t size, aligned_size; void *ptr; - int dohash = 0, r; + + if (b->alloc >= newsize) return 0; + ptr = realloc(b->ptr, newsize); + if (!ptr) return -ENOMEM; + b->ptr = ptr; + b->alloc = newsize; + return 0; +} + +static int buf_padto(struct buf *b, size_t alignment) +{ + size_t oldsize, newsize; + oldsize = b->size; + newsize = (oldsize + alignment - 1) & -alignment; + if (buf_resize(b, newsize)) return -ENOMEM; + b->size = newsize; + memset(b->ptr + oldsize, 0, newsize - oldsize); + return 0; +} + +static int buf_read_fd(struct buf *b, int fd, size_t size) +{ + ssize_t r; + + r = buf_resize(b, size); + if (r) return r; + + r = full_read(fd, b->ptr, size); + if (r == size) { + b->size = r; + return 0; + } + b->size = 0; + if (r < 0) return r; + return -EIO; +} + +static int buf_write_fd(struct buf *b, int fd) +{ + ssize_t r; + r = full_write(fd, b->ptr, b->size); + if (r == b->size) return 0; + if (r < 0) return r; + return -ENOSPC; +} + +static int buf_add_ext_header_hexdump(struct buf *b, const char *hdr, const char *value, int valuelen) +{ + size_t oldsize = b->size; + int i, len; + + /* "%u %s=%s\n" */ + len = 1 + 1 + strlen(hdr) + 1 + valuelen*2 + 1; + for (i = len; i > 9; i /= 10) len++; + + if (buf_resize(b, b->size + len)) return -ENOMEM; + b->size += snprintf(&b->ptr[b->size], len, "%u %s=", len, hdr); + for (i = 0; i < valuelen; i++) + b->size += snprintf(&b->ptr[b->size], 3, "%02x", (int)(unsigned char)value[i]); + b->ptr[b->size++] = '\n'; + + return 0; +} + +static void add_legacy_checksum(struct tar_header *hdr, const EVP_MD *md, const char *digest) +{ struct { char id[4]; uint16_t nid; uint16_t size; } mdinfo; - if (md != NULL) { - memcpy(mdinfo.id, "APK2", 4); - mdinfo.nid = EVP_MD_nid(md); - mdinfo.size = EVP_MD_size(md); - } + memcpy(mdinfo.id, "APK2", 4); + mdinfo.nid = EVP_MD_nid(md); + mdinfo.size = EVP_MD_size(md); + memcpy(&hdr->linkname[3], &mdinfo, sizeof(mdinfo)); + memcpy(&hdr->linkname[3+sizeof(mdinfo)], digest, mdinfo.size); + tarhdr_checksum(hdr); +} + +static int do_it(const EVP_MD *md, int cut) +{ + char checksumhdr[32], digest[EVP_MAX_MD_SIZE]; + struct buf data = BUF_INITIALIZER, pax = BUF_INITIALIZER; + struct tar_header hdr, paxhdr; + size_t size, aligned_size; + int dohash = 0, r, ret = 1; + + if (md) snprintf(checksumhdr, sizeof(checksumhdr), "APK-TOOLS.checksum.%s", EVP_MD_name(md)); do { if (full_read(STDIN_FILENO, &hdr, sizeof(hdr)) != sizeof(hdr)) - return 0; + goto err; if (cut && hdr.name[0] == 0) - return 0; + break; size = GET_OCTAL(hdr.size); aligned_size = (size + 511) & ~511; - if (md != NULL) - dohash = (hdr.typeflag == '0' || hdr.typeflag == '7'); + if (hdr.typeflag == 'x') { + memcpy(&paxhdr, &hdr, sizeof(hdr)); + if (buf_read_fd(&pax, STDIN_FILENO, aligned_size)) goto err; + pax.size = size; + continue; + } + + dohash = md && (hdr.typeflag == '0' || hdr.typeflag == '7' || hdr.typeflag == '2'); if (dohash) { - const unsigned char *src; - int chksum, i; - - ptr = malloc(aligned_size); - if (full_read(STDIN_FILENO, ptr, aligned_size) != aligned_size) - return 1; - - memcpy(&hdr.linkname[3], &mdinfo, sizeof(mdinfo)); - EVP_Digest(ptr, size, &hdr.linkname[3+sizeof(mdinfo)], - NULL, md, NULL); - - /* Recalculate checksum */ - memset(hdr.chksum, ' ', sizeof(hdr.chksum)); - src = (const unsigned char *) &hdr; - for (i = chksum = 0; i < sizeof(hdr); i++) - chksum += src[i]; - put_octal(hdr.chksum, sizeof(hdr.chksum)-1, chksum); + if (buf_read_fd(&data, STDIN_FILENO, aligned_size)) goto err; + + if (hdr.typeflag != '2') { + EVP_Digest(data.ptr, size, digest, NULL, md, NULL); + add_legacy_checksum(&hdr, md, digest); + } else { + EVP_Digest(hdr.linkname, strlen(hdr.linkname), digest, NULL, md, NULL); + } + + buf_add_ext_header_hexdump(&pax, checksumhdr, digest, EVP_MD_size(md)); + PUT_OCTAL(paxhdr.size, pax.size); + tarhdr_checksum(&paxhdr); + } + + if (pax.size) { + /* write pax header + content */ + if (full_write(STDOUT_FILENO, &paxhdr, sizeof(paxhdr)) != sizeof(paxhdr) || + buf_padto(&pax, 512) || + buf_write_fd(&pax, STDOUT_FILENO)) goto err; } - if (full_write(STDOUT_FILENO, &hdr, sizeof(hdr)) != sizeof(hdr)) - return 2; + if (full_write(STDOUT_FILENO, &hdr, sizeof(hdr)) != sizeof(hdr)) goto err; if (dohash) { - if (full_write(STDOUT_FILENO, ptr, aligned_size) != aligned_size) - return 2; - free(ptr); + if (buf_write_fd(&data, STDOUT_FILENO)) goto err; } else if (aligned_size != 0) { r = full_splice(STDIN_FILENO, STDOUT_FILENO, aligned_size); if (r == -1) { while (aligned_size > 0) { if (full_read(STDIN_FILENO, &hdr, sizeof(hdr)) != sizeof(hdr)) - return 1; + goto err; if (full_write(STDOUT_FILENO, &hdr, sizeof(hdr)) != sizeof(hdr)) - return 2; + goto err; aligned_size -= sizeof(hdr); } - } else if (r != aligned_size) - return 2; + } else if (r != aligned_size) goto err; } + + memset(&paxhdr, 0, sizeof(paxhdr)); + pax.size = 0; } while (1); + + ret = 0; +err: + buf_free(&data); + buf_free(&pax); + return ret; } int main(int argc, char **argv) -- cgit v1.2.3