builtin/credential-store.c

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