diff options
Diffstat (limited to 'src/usr.bin/gzsig/verify.c')
| -rw-r--r-- | src/usr.bin/gzsig/verify.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/src/usr.bin/gzsig/verify.c b/src/usr.bin/gzsig/verify.c new file mode 100644 index 0000000..f0e9373 --- /dev/null +++ b/src/usr.bin/gzsig/verify.c @@ -0,0 +1,216 @@ +/* $OpenBSD: verify.c,v 1.10 2013/03/10 10:36:57 tobias Exp $ */ + +/* + * verify.c + * + * Copyright (c) 2001 Dug Song <dugsong@arbor.net> + * Copyright (c) 2001 Arbor Networks, Inc. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The names of the copyright holders may not be used to endorse or + * promote products derived from this software without specific + * prior written permission. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL + * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; + * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * $Vendor: verify.c,v 1.3 2005/04/07 23:19:35 dugsong Exp $ + */ + +#include <sys/types.h> + +#include <openssl/ssl.h> +#include <openssl/evp.h> +#include <openssl/sha.h> + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "extern.h" +#include "gzip.h" +#include "key.h" +#include "util.h" + +static int +verify_signature(struct key *key, FILE *fin) +{ + struct gzip_header gh; + struct gzip_xfield *gx; + struct gzsig_data *gd; + u_char *sig, digest[20], buf[8192], sbuf[4096]; + SHA_CTX ctx; + int i, siglen; + + /* Read gzip header. */ + if ((i = fread((u_char *)&gh, 1, sizeof(gh), fin)) != sizeof(gh)) { + fprintf(stderr, "Error reading gzip header: %s\n", + strerror(errno)); + return (-1); + } + /* Verify gzip header. */ + if (memcmp(gh.magic, GZIP_MAGIC, sizeof(gh.magic)) != 0) { + fprintf(stderr, "Invalid gzip file\n"); + return (-1); + } else if (gh.flags & GZIP_FCONT){ + fprintf(stderr, "Multi-part gzip files not supported\n"); + return (-1); + } else if ((gh.flags & GZIP_FEXTRA) == 0) { + fprintf(stderr, "No gzip signature found\n"); + return (-1); + } + /* Read signature. */ + gx = (struct gzip_xfield *)buf; + + if ((i = fread((u_char *)gx, 1, sizeof(*gx), fin)) != sizeof(*gx)) { + fprintf(stderr, "Error reading extra field: %s\n", + strerror(errno)); + return (-1); + } + if (memcmp(gx->subfield.id, GZSIG_ID, sizeof(gx->subfield.id)) != 0) { + fprintf(stderr, "Unknown extra field\n"); + return (-1); + } + gx->subfield.len = letoh16(gx->subfield.len); + + if (gx->subfield.len <= 0 || gx->subfield.len > sizeof(sbuf)) { + fprintf(stderr, "Invalid signature length\n"); + return (-1); + } + gd = (struct gzsig_data *)sbuf; + + if ((i = fread((u_char *)gd, 1, gx->subfield.len, fin)) != + gx->subfield.len) { + fprintf(stderr, "Error reading signature: %s\n", + strerror(errno)); + return (-1); + } + /* Skip over any options. */ + if (gh.flags & GZIP_FNAME) { + if (skip_string(fin)) + return (-1); + } + if (gh.flags & GZIP_FCOMMENT) { + if (skip_string(fin)) + return (-1); + } + if (gh.flags & GZIP_FENCRYPT && + fread(buf, 1, GZIP_FENCRYPT_LEN, fin) != GZIP_FENCRYPT_LEN) + return (-1); + + /* Check signature version. */ + if (gd->version != GZSIG_VERSION) { + fprintf(stderr, "Unknown signature version: %d\n", + gd->version); + return (-1); + } + /* Compute SHA1 checksum over compressed data and trailer. */ + sig = (u_char *)(gd + 1); + siglen = gx->subfield.len - sizeof(*gd); + + SHA1_Init(&ctx); + + while ((i = fread(buf, 1, sizeof(buf), fin)) > 0) { + SHA1_Update(&ctx, buf, i); + } + SHA1_Final(digest, &ctx); + + /* Verify signature. */ + if (key_verify(key, digest, sizeof(digest), sig, siglen) < 0) { + fprintf(stderr, "Error verifying signature\n"); + return (-1); + } + return (0); +} + +void +verify_usage(void) +{ + fprintf(stderr, "usage: %s verify [-q | -v] [-f secret_file] pubkey " + "[file ...]\n", __progname); +} + +void +verify(int argc, char *argv[]) +{ + struct key *key; + char *gzipfile; + FILE *fin; + int i, error, qflag; + + qflag = 0; + + while ((i = getopt(argc, argv, "qv")) != -1) { + switch (i) { + case 'q': + qflag = 1; + break; + case 'v': + qflag = 0; + break; + default: + verify_usage(); + exit(1); + } + } + argc -= optind; + argv += optind; + + if (argc < 1) { + verify_usage(); + exit(1); + } + OpenSSL_add_all_algorithms(); + + if ((key = key_new()) == NULL) + fatal(1, "Can't initialize public key"); + + if (key_load_public(key, argv[0]) < 0) + fatal(1, "Can't load public key"); + + if (argc == 1 || *argv[1] == '-') { + argc = 0; + + if (verify_signature(key, stdin) == 0) { + if (!qflag) + fprintf(stderr, "Verified input\n"); + } else + fatal(1, "Couldn't verify input"); + } + for (i = 1; i < argc; i++) { + gzipfile = argv[i]; + + if ((fin = fopen(gzipfile, "r")) == NULL) { + fprintf(stderr, "Couldn't open %s: %s\n", + gzipfile, strerror(errno)); + continue; + } + error = verify_signature(key, fin); + fclose(fin); + + if (!error) { + if (!qflag) + fprintf(stderr, "Verified %s\n", gzipfile); + } else + fatal(1, "Couldn't verify %s", gzipfile); + } + key_free(key); +} |