builtin/credential-store.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "gettext.h"
   4 #include "lockfile.h"
   5 #include "credential.h"
   6 #include "path.h"
   7 #include "string-list.h"
   8 #include "parse-options.h"
   9 #include "write-or-die.h"
  10
  11 static struct lock_file credential_lock;
  12
  13 static int parse_credential_file(const char *fn,
  14                                   struct credential *c,
  15                                   void (*match_cb)(struct credential *),
  16                                   void (*other_cb)(struct strbuf *))
  17 {
  18         FILE *fh;
  19         struct strbuf line = STRBUF_INIT;
  20         struct credential entry = CREDENTIAL_INIT;
  21         int found_credential = 0;
  22
  23         fh = fopen(fn, "r");
  24         if (!fh) {
  25                 if (errno != ENOENT && errno != EACCES)
  26                         die_errno("unable to open %s", fn);
  27                 return found_credential;
  28         }
  29
  30         while (strbuf_getline_lf(&line, fh) != EOF) {
  31                 if (!credential_from_url_gently(&entry, line.buf, 1) &&
  32                     entry.username && entry.password &&
  33                     credential_match(c, &entry)) {
  34                         found_credential = 1;
  35                         if (match_cb) {
  36                                 match_cb(&entry);
  37                                 break;
  38                         }
  39                 }
  40                 else if (other_cb)
  41                         other_cb(&line);
  42         }
  43
  44         credential_clear(&entry);
  45         strbuf_release(&line);
  46         fclose(fh);
  47         return found_credential;
  48 }
  49
  50 static void print_entry(struct credential *c)
  51 {
  52         printf("username=%s\n", c->username);
  53         printf("password=%s\n", c->password);
  54 }
  55
  56 static void print_line(struct strbuf *buf)
  57 {
  58         strbuf_addch(buf, '\n');
  59         write_or_die(get_lock_file_fd(&credential_lock), buf->buf, buf->len);
  60 }
  61
  62 static void rewrite_credential_file(const char *fn, struct credential *c,
  63                                     struct strbuf *extra)
  64 {
  65         int timeout_ms = 1000;
  66
  67         git_config_get_int("credentialstore.locktimeoutms", &timeout_ms);
  68         if (hold_lock_file_for_update_timeout(&credential_lock, fn, 0, timeout_ms) < 0)
  69                 die_errno(_("unable to get credential storage lock in %d ms"), timeout_ms);
  70         if (extra)
  71                 print_line(extra);
  72         parse_credential_file(fn, c, NULL, print_line);
  73         if (commit_lock_file(&credential_lock) < 0)
  74                 die_errno("unable to write credential store");
  75 }
  76
  77 static void store_credential_file(const char *fn, struct credential *c)
  78 {
  79         struct strbuf buf = STRBUF_INIT;
  80
  81         strbuf_addf(&buf, "%s://", c->protocol);
  82         strbuf_addstr_urlencode(&buf, c->username, is_rfc3986_unreserved);
  83         strbuf_addch(&buf, ':');
  84         strbuf_addstr_urlencode(&buf, c->password, is_rfc3986_unreserved);
  85         strbuf_addch(&buf, '@');
  86         if (c->host)
  87                 strbuf_addstr_urlencode(&buf, c->host, is_rfc3986_unreserved);
  88         if (c->path) {
  89                 strbuf_addch(&buf, '/');
  90                 strbuf_addstr_urlencode(&buf, c->path,
  91                                         is_rfc3986_reserved_or_unreserved);
  92         }
  93
  94         rewrite_credential_file(fn, c, &buf);
  95         strbuf_release(&buf);
  96 }
  97
  98 static void store_credential(const struct string_list *fns, struct credential *c)
  99 {
 100         struct string_list_item *fn;
 101
 102         /*
 103          * Sanity check that what we are storing is actually sensible.
 104          * In particular, we can't make a URL without a protocol field.
 105          * Without either a host or pathname (depending on the scheme),
 106          * we have no primary key. And without a username and password,
 107          * we are not actually storing a credential.
 108          */
 109         if (!c->protocol || !(c->host || c->path) || !c->username || !c->password)
 110                 return;
 111
 112         for_each_string_list_item(fn, fns)
 113                 if (!access(fn->string, F_OK)) {
 114                         store_credential_file(fn->string, c);
 115                         return;
 116                 }
 117         /*
 118          * Write credential to the filename specified by fns->items[0], thus
 119          * creating it
 120          */
 121         if (fns->nr)
 122                 store_credential_file(fns->items[0].string, c);
 123 }
 124
 125 static void remove_credential(const struct string_list *fns, struct credential *c)
 126 {
 127         struct string_list_item *fn;
 128
 129         /*
 130          * Sanity check that we actually have something to match
 131          * against. The input we get is a restrictive pattern,
 132          * so technically a blank credential means "erase everything".
 133          * But it is too easy to accidentally send this, since it is equivalent
 134          * to empty input. So explicitly disallow it, and require that the
 135          * pattern have some actual content to match.
 136          */
 137         if (!c->protocol && !c->host && !c->path && !c->username)
 138                 return;
 139         for_each_string_list_item(fn, fns)
 140                 if (!access(fn->string, F_OK))
 141                         rewrite_credential_file(fn->string, c, NULL);
 142 }
 143
 144 static void lookup_credential(const struct string_list *fns, struct credential *c)
 145 {
 146         struct string_list_item *fn;
 147
 148         for_each_string_list_item(fn, fns)
 149                 if (parse_credential_file(fn->string, c, print_entry, NULL))
 150                         return; /* Found credential */
 151 }
 152
 153 int cmd_credential_store(int argc, const char **argv, const char *prefix)
 154 {
 155         const char * const usage[] = {
 156                 "git credential-store [<options>] <action>",
 157                 NULL
 158         };
 159         const char *op;
 160         struct credential c = CREDENTIAL_INIT;
 161         struct string_list fns = STRING_LIST_INIT_DUP;
 162         char *file = NULL;
 163         struct option options[] = {
 164                 OPT_STRING(0, "file", &file, "path",
 165                            "fetch and store credentials in <path>"),
 166                 OPT_END()
 167         };
 168
 169         umask(077);
 170
 171         argc = parse_options(argc, (const char **)argv, prefix, options, usage, 0);
 172         if (argc != 1)
 173                 usage_with_options(usage, options);
 174         op = argv[0];
 175
 176         if (file) {
 177                 string_list_append(&fns, file);
 178         } else {
 179                 if ((file = interpolate_path("~/.git-credentials", 0)))
 180                         string_list_append_nodup(&fns, file);
 181                 file = xdg_config_home("credentials");
 182                 if (file)
 183                         string_list_append_nodup(&fns, file);
 184         }
 185         if (!fns.nr)
 186                 die("unable to set up default path; use --file");
 187
 188         if (credential_read(&c, stdin) < 0)
 189                 die("unable to read credential");
 190
 191         if (!strcmp(op, "get"))
 192                 lookup_credential(&fns, &c);
 193         else if (!strcmp(op, "erase"))
 194                 remove_credential(&fns, &c);
 195         else if (!strcmp(op, "store"))
 196                 store_credential(&fns, &c);
 197         else
 198                 ; /* Ignore unknown operation. */
 199
 200         string_list_clear(&fns, 0);
 201         return 0;
 202 }