builtin/verify-tag.c

   1 /*
   2  * Builtin "git verify-tag"
   3  *
   4  * Copyright (c) 2007 Carlos Rica <jasampler@gmail.com>
   5  *
   6  * Based on git-verify-tag.sh
   7  */
   8 #include "cache.h"
   9 #include "builtin.h"
  10 #include "tag.h"
  11 #include "run-command.h"
  12 #include <signal.h>
  13 #include "parse-options.h"
  14
  15 static const char * const verify_tag_usage[] = {
  16                 "git verify-tag [-v|--verbose] <tag>...",
  17                 NULL
  18 };
  19
  20 static int run_gpg_verify(const char *buf, unsigned long size, int verbose)
  21 {
  22         struct child_process gpg;
  23         const char *args_gpg[] = {"gpg", "--verify", "FILE", "-", NULL};
  24         char path[PATH_MAX];
  25         size_t len;
  26         int fd, ret;
  27
  28         fd = git_mkstemp(path, PATH_MAX, ".git_vtag_tmpXXXXXX");
  29         if (fd < 0)
  30                 return error("could not create temporary file '%s': %s",
  31                                                 path, strerror(errno));
  32         if (write_in_full(fd, buf, size) < 0)
  33                 return error("failed writing temporary file '%s': %s",
  34                                                 path, strerror(errno));
  35         close(fd);
  36
  37         /* find the length without signature */
  38         len = parse_signature(buf, size);
  39         if (verbose)
  40                 write_in_full(1, buf, len);
  41
  42         memset(&gpg, 0, sizeof(gpg));
  43         gpg.argv = args_gpg;
  44         gpg.in = -1;
  45         args_gpg[2] = path;
  46         if (start_command(&gpg)) {
  47                 unlink(path);
  48                 return error("could not run gpg.");
  49         }
  50
  51         write_in_full(gpg.in, buf, len);
  52         close(gpg.in);
  53         ret = finish_command(&gpg);
  54
  55         unlink_or_warn(path);
  56
  57         return ret;
  58 }
  59
  60 static int verify_tag(const char *name, int verbose)
  61 {
  62         enum object_type type;
  63         unsigned char sha1[20];
  64         char *buf;
  65         unsigned long size;
  66         int ret;
  67
  68         if (get_sha1(name, sha1))
  69                 return error("tag '%s' not found.", name);
  70
  71         type = sha1_object_info(sha1, NULL);
  72         if (type != OBJ_TAG)
  73                 return error("%s: cannot verify a non-tag object of type %s.",
  74                                 name, typename(type));
  75
  76         buf = read_sha1_file(sha1, &type, &size);
  77         if (!buf)
  78                 return error("%s: unable to read file.", name);
  79
  80         ret = run_gpg_verify(buf, size, verbose);
  81
  82         free(buf);
  83         return ret;
  84 }
  85
  86 int cmd_verify_tag(int argc, const char **argv, const char *prefix)
  87 {
  88         int i = 1, verbose = 0, had_error = 0;
  89         const struct option verify_tag_options[] = {
  90                 OPT__VERBOSE(&verbose, "print tag contents"),
  91                 OPT_END()
  92         };
  93
  94         git_config(git_default_config, NULL);
  95
  96         argc = parse_options(argc, argv, prefix, verify_tag_options,
  97                              verify_tag_usage, PARSE_OPT_KEEP_ARGV0);
  98         if (argc <= i)
  99                 usage_with_options(verify_tag_usage, verify_tag_options);
 100
 101         /* sometimes the program was terminated because this signal
 102          * was received in the process of writing the gpg input: */
 103         signal(SIGPIPE, SIG_IGN);
 104         while (i < argc)
 105                 if (verify_tag(argv[i++], verbose))
 106                         had_error = 1;
 107         return had_error;
 108 }