Andrew's git - gitweb.git/blob - contrib/credential/libsecret/git-credential-libsecret.c

   1/*
   2 * Copyright (C) 2011 John Szakmeister <john@szakmeister.net>
   3 *               2012 Philipp A. Hartmann <pah@qo.cx>
   4 *               2016 Mantas Mikulėnas <grawity@gmail.com>
   5 *
   6 *  This program is free software; you can redistribute it and/or modify
   7 *  it under the terms of the GNU General Public License as published by
   8 *  the Free Software Foundation; either version 2 of the License, or
   9 *  (at your option) any later version.
  10 *
  11 *  This program is distributed in the hope that it will be useful,
  12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 *  GNU General Public License for more details.
  15 *
  16 *  You should have received a copy of the GNU General Public License
  17 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20/*
  21 * Credits:
  22 * - GNOME Keyring API handling originally written by John Szakmeister
  23 * - ported to credential helper API by Philipp A. Hartmann
  24 */
  25
  26#include <stdio.h>
  27#include <string.h>
  28#include <stdlib.h>
  29#include <glib.h>
  30#include <libsecret/secret.h>
  31
  32/*
  33 * This credential struct and API is simplified from git's credential.{h,c}
  34 */
  35struct credential {
  36        char *protocol;
  37        char *host;
  38        unsigned short port;
  39        char *path;
  40        char *username;
  41        char *password;
  42};
  43
  44#define CREDENTIAL_INIT { NULL, NULL, 0, NULL, NULL, NULL }
  45
  46typedef int (*credential_op_cb)(struct credential *);
  47
  48struct credential_operation {
  49        char *name;
  50        credential_op_cb op;
  51};
  52
  53#define CREDENTIAL_OP_END { NULL, NULL }
  54
  55/* ----------------- Secret Service functions ----------------- */
  56
  57static char *make_label(struct credential *c)
  58{
  59        if (c->port)
  60                return g_strdup_printf("Git: %s://%s:%hu/%s",
  61                                        c->protocol, c->host, c->port, c->path ? c->path : "");
  62        else
  63                return g_strdup_printf("Git: %s://%s/%s",
  64                                        c->protocol, c->host, c->path ? c->path : "");
  65}
  66
  67static GHashTable *make_attr_list(struct credential *c)
  68{
  69        GHashTable *al = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, g_free);
  70
  71        if (c->username)
  72                g_hash_table_insert(al, "user", g_strdup(c->username));
  73        if (c->protocol)
  74                g_hash_table_insert(al, "protocol", g_strdup(c->protocol));
  75        if (c->host)
  76                g_hash_table_insert(al, "server", g_strdup(c->host));
  77        if (c->port)
  78                g_hash_table_insert(al, "port", g_strdup_printf("%hu", c->port));
  79        if (c->path)
  80                g_hash_table_insert(al, "object", g_strdup(c->path));
  81
  82        return al;
  83}
  84
  85static int keyring_get(struct credential *c)
  86{
  87        SecretService *service = NULL;
  88        GHashTable *attributes = NULL;
  89        GError *error = NULL;
  90        GList *items = NULL;
  91
  92        if (!c->protocol || !(c->host || c->path))
  93                return EXIT_FAILURE;
  94
  95        service = secret_service_get_sync(0, NULL, &error);
  96        if (error != NULL) {
  97                g_critical("could not connect to Secret Service: %s", error->message);
  98                g_error_free(error);
  99                return EXIT_FAILURE;
 100        }
 101
 102        attributes = make_attr_list(c);
 103        items = secret_service_search_sync(service,
 104                                           SECRET_SCHEMA_COMPAT_NETWORK,
 105                                           attributes,
 106                                           SECRET_SEARCH_LOAD_SECRETS | SECRET_SEARCH_UNLOCK,
 107                                           NULL,
 108                                           &error);
 109        g_hash_table_unref(attributes);
 110        if (error != NULL) {
 111                g_critical("lookup failed: %s", error->message);
 112                g_error_free(error);
 113                return EXIT_FAILURE;
 114        }
 115
 116        if (items != NULL) {
 117                SecretItem *item;
 118                SecretValue *secret;
 119                const char *s;
 120
 121                item = items->data;
 122                secret = secret_item_get_secret(item);
 123                attributes = secret_item_get_attributes(item);
 124
 125                s = g_hash_table_lookup(attributes, "user");
 126                if (s) {
 127                        g_free(c->username);
 128                        c->username = g_strdup(s);
 129                }
 130
 131                s = secret_value_get_text(secret);
 132                if (s) {
 133                        g_free(c->password);
 134                        c->password = g_strdup(s);
 135                }
 136
 137                g_hash_table_unref(attributes);
 138                secret_value_unref(secret);
 139                g_list_free_full(items, g_object_unref);
 140        }
 141
 142        return EXIT_SUCCESS;
 143}
 144
 145
 146static int keyring_store(struct credential *c)
 147{
 148        char *label = NULL;
 149        GHashTable *attributes = NULL;
 150        GError *error = NULL;
 151
 152        /*
 153         * Sanity check that what we are storing is actually sensible.
 154         * In particular, we can't make a URL without a protocol field.
 155         * Without either a host or pathname (depending on the scheme),
 156         * we have no primary key. And without a username and password,
 157         * we are not actually storing a credential.
 158         */
 159        if (!c->protocol || !(c->host || c->path) ||
 160            !c->username || !c->password)
 161                return EXIT_FAILURE;
 162
 163        label = make_label(c);
 164        attributes = make_attr_list(c);
 165        secret_password_storev_sync(SECRET_SCHEMA_COMPAT_NETWORK,
 166                                    attributes,
 167                                    NULL,
 168                                    label,
 169                                    c->password,
 170                                    NULL,
 171                                    &error);
 172        g_free(label);
 173        g_hash_table_unref(attributes);
 174
 175        if (error != NULL) {
 176                g_critical("store failed: %s", error->message);
 177                g_error_free(error);
 178                return EXIT_FAILURE;
 179        }
 180
 181        return EXIT_SUCCESS;
 182}
 183
 184static int keyring_erase(struct credential *c)
 185{
 186        GHashTable *attributes = NULL;
 187        GError *error = NULL;
 188
 189        /*
 190         * Sanity check that we actually have something to match
 191         * against. The input we get is a restrictive pattern,
 192         * so technically a blank credential means "erase everything".
 193         * But it is too easy to accidentally send this, since it is equivalent
 194         * to empty input. So explicitly disallow it, and require that the
 195         * pattern have some actual content to match.
 196         */
 197        if (!c->protocol && !c->host && !c->path && !c->username)
 198                return EXIT_FAILURE;
 199
 200        attributes = make_attr_list(c);
 201        secret_password_clearv_sync(SECRET_SCHEMA_COMPAT_NETWORK,
 202                                    attributes,
 203                                    NULL,
 204                                    &error);
 205        g_hash_table_unref(attributes);
 206
 207        if (error != NULL) {
 208                g_critical("erase failed: %s", error->message);
 209                g_error_free(error);
 210                return EXIT_FAILURE;
 211        }
 212
 213        return EXIT_SUCCESS;
 214}
 215
 216/*
 217 * Table with helper operation callbacks, used by generic
 218 * credential helper main function.
 219 */
 220static struct credential_operation const credential_helper_ops[] = {
 221        { "get",   keyring_get },
 222        { "store", keyring_store },
 223        { "erase", keyring_erase },
 224        CREDENTIAL_OP_END
 225};
 226
 227/* ------------------ credential functions ------------------ */
 228
 229static void credential_init(struct credential *c)
 230{
 231        memset(c, 0, sizeof(*c));
 232}
 233
 234static void credential_clear(struct credential *c)
 235{
 236        g_free(c->protocol);
 237        g_free(c->host);
 238        g_free(c->path);
 239        g_free(c->username);
 240        g_free(c->password);
 241
 242        credential_init(c);
 243}
 244
 245static int credential_read(struct credential *c)
 246{
 247        char *buf;
 248        size_t line_len;
 249        char *key;
 250        char *value;
 251
 252        key = buf = g_malloc(1024);
 253
 254        while (fgets(buf, 1024, stdin)) {
 255                line_len = strlen(buf);
 256
 257                if (line_len && buf[line_len-1] == '\n')
 258                        buf[--line_len] = '\0';
 259
 260                if (!line_len)
 261                        break;
 262
 263                value = strchr(buf, '=');
 264                if (!value) {
 265                        g_warning("invalid credential line: %s", key);
 266                        g_free(buf);
 267                        return -1;
 268                }
 269                *value++ = '\0';
 270
 271                if (!strcmp(key, "protocol")) {
 272                        g_free(c->protocol);
 273                        c->protocol = g_strdup(value);
 274                } else if (!strcmp(key, "host")) {
 275                        g_free(c->host);
 276                        c->host = g_strdup(value);
 277                        value = strrchr(c->host, ':');
 278                        if (value) {
 279                                *value++ = '\0';
 280                                c->port = atoi(value);
 281                        }
 282                } else if (!strcmp(key, "path")) {
 283                        g_free(c->path);
 284                        c->path = g_strdup(value);
 285                } else if (!strcmp(key, "username")) {
 286                        g_free(c->username);
 287                        c->username = g_strdup(value);
 288                } else if (!strcmp(key, "password")) {
 289                        g_free(c->password);
 290                        c->password = g_strdup(value);
 291                        while (*value)
 292                                *value++ = '\0';
 293                }
 294                /*
 295                 * Ignore other lines; we don't know what they mean, but
 296                 * this future-proofs us when later versions of git do
 297                 * learn new lines, and the helpers are updated to match.
 298                 */
 299        }
 300
 301        g_free(buf);
 302
 303        return 0;
 304}
 305
 306static void credential_write_item(FILE *fp, const char *key, const char *value)
 307{
 308        if (!value)
 309                return;
 310        fprintf(fp, "%s=%s\n", key, value);
 311}
 312
 313static void credential_write(const struct credential *c)
 314{
 315        /* only write username/password, if set */
 316        credential_write_item(stdout, "username", c->username);
 317        credential_write_item(stdout, "password", c->password);
 318}
 319
 320static void usage(const char *name)
 321{
 322        struct credential_operation const *try_op = credential_helper_ops;
 323        const char *basename = strrchr(name, '/');
 324
 325        basename = (basename) ? basename + 1 : name;
 326        fprintf(stderr, "usage: %s <", basename);
 327        while (try_op->name) {
 328                fprintf(stderr, "%s", (try_op++)->name);
 329                if (try_op->name)
 330                        fprintf(stderr, "%s", "|");
 331        }
 332        fprintf(stderr, "%s", ">\n");
 333}
 334
 335int main(int argc, char *argv[])
 336{
 337        int ret = EXIT_SUCCESS;
 338
 339        struct credential_operation const *try_op = credential_helper_ops;
 340        struct credential cred = CREDENTIAL_INIT;
 341
 342        if (!argv[1]) {
 343                usage(argv[0]);
 344                exit(EXIT_FAILURE);
 345        }
 346
 347        g_set_application_name("Git Credential Helper");
 348
 349        /* lookup operation callback */
 350        while (try_op->name && strcmp(argv[1], try_op->name))
 351                try_op++;
 352
 353        /* unsupported operation given -- ignore silently */
 354        if (!try_op->name || !try_op->op)
 355                goto out;
 356
 357        ret = credential_read(&cred);
 358        if (ret)
 359                goto out;
 360
 361        /* perform credential operation */
 362        ret = (*try_op->op)(&cred);
 363
 364        credential_write(&cred);
 365
 366out:
 367        credential_clear(&cred);
 368        return ret;
 369}