tag.c

   1 #include "git-compat-util.h"
   2 #include "environment.h"
   3 #include "tag.h"
   4 #include "object-name.h"
   5 #include "object-store.h"
   6 #include "commit.h"
   7 #include "tree.h"
   8 #include "blob.h"
   9 #include "alloc.h"
  10 #include "gpg-interface.h"
  11 #include "hex.h"
  12 #include "packfile.h"
  13 #include "wrapper.h"
  14
  15 const char *tag_type = "tag";
  16
  17 static int run_gpg_verify(const char *buf, unsigned long size, unsigned flags)
  18 {
  19         struct signature_check sigc;
  20         struct strbuf payload = STRBUF_INIT;
  21         struct strbuf signature = STRBUF_INIT;
  22         int ret;
  23
  24         memset(&sigc, 0, sizeof(sigc));
  25
  26         if (!parse_signature(buf, size, &payload, &signature)) {
  27                 if (flags & GPG_VERIFY_VERBOSE)
  28                         write_in_full(1, buf, size);
  29                 return error("no signature found");
  30         }
  31
  32         sigc.payload_type = SIGNATURE_PAYLOAD_TAG;
  33         sigc.payload = strbuf_detach(&payload, &sigc.payload_len);
  34         ret = check_signature(&sigc, signature.buf, signature.len);
  35
  36         if (!(flags & GPG_VERIFY_OMIT_STATUS))
  37                 print_signature_buffer(&sigc, flags);
  38
  39         signature_check_clear(&sigc);
  40         strbuf_release(&payload);
  41         strbuf_release(&signature);
  42         return ret;
  43 }
  44
  45 int gpg_verify_tag(const struct object_id *oid, const char *name_to_report,
  46                 unsigned flags)
  47 {
  48         enum object_type type;
  49         char *buf;
  50         unsigned long size;
  51         int ret;
  52
  53         type = oid_object_info(the_repository, oid, NULL);
  54         if (type != OBJ_TAG)
  55                 return error("%s: cannot verify a non-tag object of type %s.",
  56                                 name_to_report ?
  57                                 name_to_report :
  58                                 repo_find_unique_abbrev(the_repository, oid, DEFAULT_ABBREV),
  59                                 type_name(type));
  60
  61         buf = repo_read_object_file(the_repository, oid, &type, &size);
  62         if (!buf)
  63                 return error("%s: unable to read file.",
  64                                 name_to_report ?
  65                                 name_to_report :
  66                                 repo_find_unique_abbrev(the_repository, oid, DEFAULT_ABBREV));
  67
  68         ret = run_gpg_verify(buf, size, flags);
  69
  70         free(buf);
  71         return ret;
  72 }
  73
  74 struct object *deref_tag(struct repository *r, struct object *o, const char *warn, int warnlen)
  75 {
  76         struct object_id *last_oid = NULL;
  77         while (o && o->type == OBJ_TAG)
  78                 if (((struct tag *)o)->tagged) {
  79                         last_oid = &((struct tag *)o)->tagged->oid;
  80                         o = parse_object(r, last_oid);
  81                 } else {
  82                         last_oid = NULL;
  83                         o = NULL;
  84                 }
  85         if (!o && warn) {
  86                 if (last_oid && is_promisor_object(last_oid))
  87                         return NULL;
  88                 if (!warnlen)
  89                         warnlen = strlen(warn);
  90                 error("missing object referenced by '%.*s'", warnlen, warn);
  91         }
  92         return o;
  93 }
  94
  95 struct object *deref_tag_noverify(struct object *o)
  96 {
  97         while (o && o->type == OBJ_TAG) {
  98                 o = parse_object(the_repository, &o->oid);
  99                 if (o && o->type == OBJ_TAG && ((struct tag *)o)->tagged)
 100                         o = ((struct tag *)o)->tagged;
 101                 else
 102                         o = NULL;
 103         }
 104         return o;
 105 }
 106
 107 struct tag *lookup_tag(struct repository *r, const struct object_id *oid)
 108 {
 109         struct object *obj = lookup_object(r, oid);
 110         if (!obj)
 111                 return create_object(r, oid, alloc_tag_node(r));
 112         return object_as_type(obj, OBJ_TAG, 0);
 113 }
 114
 115 static timestamp_t parse_tag_date(const char *buf, const char *tail)
 116 {
 117         const char *dateptr;
 118
 119         while (buf < tail && *buf++ != '>')
 120                 /* nada */;
 121         if (buf >= tail)
 122                 return 0;
 123         dateptr = buf;
 124         while (buf < tail && *buf++ != '\n')
 125                 /* nada */;
 126         if (buf >= tail)
 127                 return 0;
 128         /* dateptr < buf && buf[-1] == '\n', so parsing will stop at buf-1 */
 129         return parse_timestamp(dateptr, NULL, 10);
 130 }
 131
 132 void release_tag_memory(struct tag *t)
 133 {
 134         free(t->tag);
 135         t->tagged = NULL;
 136         t->object.parsed = 0;
 137         t->date = 0;
 138 }
 139
 140 int parse_tag_buffer(struct repository *r, struct tag *item, const void *data, unsigned long size)
 141 {
 142         struct object_id oid;
 143         char type[20];
 144         const char *bufptr = data;
 145         const char *tail = bufptr + size;
 146         const char *nl;
 147
 148         if (item->object.parsed)
 149                 return 0;
 150
 151         if (item->tag) {
 152                 /*
 153                  * Presumably left over from a previous failed parse;
 154                  * clear it out in preparation for re-parsing (we'll probably
 155                  * hit the same error, which lets us tell our current caller
 156                  * about the problem).
 157                  */
 158                 FREE_AND_NULL(item->tag);
 159         }
 160
 161         if (size < the_hash_algo->hexsz + 24)
 162                 return -1;
 163         if (memcmp("object ", bufptr, 7) || parse_oid_hex(bufptr + 7, &oid, &bufptr) || *bufptr++ != '\n')
 164                 return -1;
 165
 166         if (!starts_with(bufptr, "type "))
 167                 return -1;
 168         bufptr += 5;
 169         nl = memchr(bufptr, '\n', tail - bufptr);
 170         if (!nl || sizeof(type) <= (nl - bufptr))
 171                 return -1;
 172         memcpy(type, bufptr, nl - bufptr);
 173         type[nl - bufptr] = '\0';
 174         bufptr = nl + 1;
 175
 176         if (!strcmp(type, blob_type)) {
 177                 item->tagged = (struct object *)lookup_blob(r, &oid);
 178         } else if (!strcmp(type, tree_type)) {
 179                 item->tagged = (struct object *)lookup_tree(r, &oid);
 180         } else if (!strcmp(type, commit_type)) {
 181                 item->tagged = (struct object *)lookup_commit(r, &oid);
 182         } else if (!strcmp(type, tag_type)) {
 183                 item->tagged = (struct object *)lookup_tag(r, &oid);
 184         } else {
 185                 return error("unknown tag type '%s' in %s",
 186                              type, oid_to_hex(&item->object.oid));
 187         }
 188
 189         if (!item->tagged)
 190                 return error("bad tag pointer to %s in %s",
 191                              oid_to_hex(&oid),
 192                              oid_to_hex(&item->object.oid));
 193
 194         if (bufptr + 4 < tail && starts_with(bufptr, "tag "))
 195                 ;               /* good */
 196         else
 197                 return -1;
 198         bufptr += 4;
 199         nl = memchr(bufptr, '\n', tail - bufptr);
 200         if (!nl)
 201                 return -1;
 202         item->tag = xmemdupz(bufptr, nl - bufptr);
 203         bufptr = nl + 1;
 204
 205         if (bufptr + 7 < tail && starts_with(bufptr, "tagger "))
 206                 item->date = parse_tag_date(bufptr, tail);
 207         else
 208                 item->date = 0;
 209
 210         item->object.parsed = 1;
 211         return 0;
 212 }
 213
 214 int parse_tag(struct tag *item)
 215 {
 216         enum object_type type;
 217         void *data;
 218         unsigned long size;
 219         int ret;
 220
 221         if (item->object.parsed)
 222                 return 0;
 223         data = repo_read_object_file(the_repository, &item->object.oid, &type,
 224                                      &size);
 225         if (!data)
 226                 return error("Could not read %s",
 227                              oid_to_hex(&item->object.oid));
 228         if (type != OBJ_TAG) {
 229                 free(data);
 230                 return error("Object %s not a tag",
 231                              oid_to_hex(&item->object.oid));
 232         }
 233         ret = parse_tag_buffer(the_repository, item, data, size);
 234         free(data);
 235         return ret;
 236 }
 237
 238 struct object_id *get_tagged_oid(struct tag *tag)
 239 {
 240         if (!tag->tagged)
 241                 die("bad tag");
 242         return &tag->tagged->oid;
 243 }