Andrew's git / gitweb.git / credential.c
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credential.con commit mergetools/meld: make usage of `--output` configurable and more robust (b12d045)
   1#include "cache.h"
   2#include "credential.h"
   3#include "string-list.h"
   4#include "run-command.h"
   5#include "url.h"
   6#include "prompt.h"
   7
   8void credential_init(struct credential *c)
   9{
  10        memset(c, 0, sizeof(*c));
  11        c->helpers.strdup_strings = 1;
  12}
  13
  14void credential_clear(struct credential *c)
  15{
  16        free(c->protocol);
  17        free(c->host);
  18        free(c->path);
  19        free(c->username);
  20        free(c->password);
  21        string_list_clear(&c->helpers, 0);
  22
  23        credential_init(c);
  24}
  25
  26int credential_match(const struct credential *want,
  27                     const struct credential *have)
  28{
  29#define CHECK(x) (!want->x || (have->x && !strcmp(want->x, have->x)))
  30        return CHECK(protocol) &&
  31               CHECK(host) &&
  32               CHECK(path) &&
  33               CHECK(username);
  34#undef CHECK
  35}
  36
  37static int credential_config_callback(const char *var, const char *value,
  38                                      void *data)
  39{
  40        struct credential *c = data;
  41        const char *key, *dot;
  42
  43        if (!skip_prefix(var, "credential.", &key))
  44                return 0;
  45
  46        if (!value)
  47                return config_error_nonbool(var);
  48
  49        dot = strrchr(key, '.');
  50        if (dot) {
  51                struct credential want = CREDENTIAL_INIT;
  52                char *url = xmemdupz(key, dot - key);
  53                int matched;
  54
  55                credential_from_url(&want, url);
  56                matched = credential_match(&want, c);
  57
  58                credential_clear(&want);
  59                free(url);
  60
  61                if (!matched)
  62                        return 0;
  63                key = dot + 1;
  64        }
  65
  66        if (!strcmp(key, "helper"))
  67                string_list_append(&c->helpers, value);
  68        else if (!strcmp(key, "username")) {
  69                if (!c->username)
  70                        c->username = xstrdup(value);
  71        }
  72        else if (!strcmp(key, "usehttppath"))
  73                c->use_http_path = git_config_bool(var, value);
  74
  75        return 0;
  76}
  77
  78static int proto_is_http(const char *s)
  79{
  80        if (!s)
  81                return 0;
  82        return !strcmp(s, "https") || !strcmp(s, "http");
  83}
  84
  85static void credential_apply_config(struct credential *c)
  86{
  87        if (c->configured)
  88                return;
  89        git_config(credential_config_callback, c);
  90        c->configured = 1;
  91
  92        if (!c->use_http_path && proto_is_http(c->protocol)) {
  93                free(c->path);
  94                c->path = NULL;
  95        }
  96}
  97
  98static void credential_describe(struct credential *c, struct strbuf *out)
  99{
 100        if (!c->protocol)
 101                return;
 102        strbuf_addf(out, "%s://", c->protocol);
 103        if (c->username && *c->username)
 104                strbuf_addf(out, "%s@", c->username);
 105        if (c->host)
 106                strbuf_addstr(out, c->host);
 107        if (c->path)
 108                strbuf_addf(out, "/%s", c->path);
 109}
 110
 111static char *credential_ask_one(const char *what, struct credential *c,
 112                                int flags)
 113{
 114        struct strbuf desc = STRBUF_INIT;
 115        struct strbuf prompt = STRBUF_INIT;
 116        char *r;
 117
 118        credential_describe(c, &desc);
 119        if (desc.len)
 120                strbuf_addf(&prompt, "%s for '%s': ", what, desc.buf);
 121        else
 122                strbuf_addf(&prompt, "%s: ", what);
 123
 124        r = git_prompt(prompt.buf, flags);
 125
 126        strbuf_release(&desc);
 127        strbuf_release(&prompt);
 128        return xstrdup(r);
 129}
 130
 131static void credential_getpass(struct credential *c)
 132{
 133        if (!c->username)
 134                c->username = credential_ask_one("Username", c,
 135                                                 PROMPT_ASKPASS|PROMPT_ECHO);
 136        if (!c->password)
 137                c->password = credential_ask_one("Password", c,
 138                                                 PROMPT_ASKPASS);
 139}
 140
 141int credential_read(struct credential *c, FILE *fp)
 142{
 143        struct strbuf line = STRBUF_INIT;
 144
 145        while (strbuf_getline(&line, fp, '\n') != EOF) {
 146                char *key = line.buf;
 147                char *value = strchr(key, '=');
 148
 149                if (!line.len)
 150                        break;
 151
 152                if (!value) {
 153                        warning("invalid credential line: %s", key);
 154                        strbuf_release(&line);
 155                        return -1;
 156                }
 157                *value++ = '\0';
 158
 159                if (!strcmp(key, "username")) {
 160                        free(c->username);
 161                        c->username = xstrdup(value);
 162                } else if (!strcmp(key, "password")) {
 163                        free(c->password);
 164                        c->password = xstrdup(value);
 165                } else if (!strcmp(key, "protocol")) {
 166                        free(c->protocol);
 167                        c->protocol = xstrdup(value);
 168                } else if (!strcmp(key, "host")) {
 169                        free(c->host);
 170                        c->host = xstrdup(value);
 171                } else if (!strcmp(key, "path")) {
 172                        free(c->path);
 173                        c->path = xstrdup(value);
 174                } else if (!strcmp(key, "url")) {
 175                        credential_from_url(c, value);
 176                }
 177                /*
 178                 * Ignore other lines; we don't know what they mean, but
 179                 * this future-proofs us when later versions of git do
 180                 * learn new lines, and the helpers are updated to match.
 181                 */
 182        }
 183
 184        strbuf_release(&line);
 185        return 0;
 186}
 187
 188static void credential_write_item(FILE *fp, const char *key, const char *value)
 189{
 190        if (!value)
 191                return;
 192        fprintf(fp, "%s=%s\n", key, value);
 193}
 194
 195void credential_write(const struct credential *c, FILE *fp)
 196{
 197        credential_write_item(fp, "protocol", c->protocol);
 198        credential_write_item(fp, "host", c->host);
 199        credential_write_item(fp, "path", c->path);
 200        credential_write_item(fp, "username", c->username);
 201        credential_write_item(fp, "password", c->password);
 202}
 203
 204static int run_credential_helper(struct credential *c,
 205                                 const char *cmd,
 206                                 int want_output)
 207{
 208        struct child_process helper;
 209        const char *argv[] = { NULL, NULL };
 210        FILE *fp;
 211
 212        memset(&helper, 0, sizeof(helper));
 213        argv[0] = cmd;
 214        helper.argv = argv;
 215        helper.use_shell = 1;
 216        helper.in = -1;
 217        if (want_output)
 218                helper.out = -1;
 219        else
 220                helper.no_stdout = 1;
 221
 222        if (start_command(&helper) < 0)
 223                return -1;
 224
 225        fp = xfdopen(helper.in, "w");
 226        credential_write(c, fp);
 227        fclose(fp);
 228
 229        if (want_output) {
 230                int r;
 231                fp = xfdopen(helper.out, "r");
 232                r = credential_read(c, fp);
 233                fclose(fp);
 234                if (r < 0) {
 235                        finish_command(&helper);
 236                        return -1;
 237                }
 238        }
 239
 240        if (finish_command(&helper))
 241                return -1;
 242        return 0;
 243}
 244
 245static int credential_do(struct credential *c, const char *helper,
 246                         const char *operation)
 247{
 248        struct strbuf cmd = STRBUF_INIT;
 249        int r;
 250
 251        if (helper[0] == '!')
 252                strbuf_addstr(&cmd, helper + 1);
 253        else if (is_absolute_path(helper))
 254                strbuf_addstr(&cmd, helper);
 255        else
 256                strbuf_addf(&cmd, "git credential-%s", helper);
 257
 258        strbuf_addf(&cmd, " %s", operation);
 259        r = run_credential_helper(c, cmd.buf, !strcmp(operation, "get"));
 260
 261        strbuf_release(&cmd);
 262        return r;
 263}
 264
 265void credential_fill(struct credential *c)
 266{
 267        int i;
 268
 269        if (c->username && c->password)
 270                return;
 271
 272        credential_apply_config(c);
 273
 274        for (i = 0; i < c->helpers.nr; i++) {
 275                credential_do(c, c->helpers.items[i].string, "get");
 276                if (c->username && c->password)
 277                        return;
 278        }
 279
 280        credential_getpass(c);
 281        if (!c->username && !c->password)
 282                die("unable to get password from user");
 283}
 284
 285void credential_approve(struct credential *c)
 286{
 287        int i;
 288
 289        if (c->approved)
 290                return;
 291        if (!c->username || !c->password)
 292                return;
 293
 294        credential_apply_config(c);
 295
 296        for (i = 0; i < c->helpers.nr; i++)
 297                credential_do(c, c->helpers.items[i].string, "store");
 298        c->approved = 1;
 299}
 300
 301void credential_reject(struct credential *c)
 302{
 303        int i;
 304
 305        credential_apply_config(c);
 306
 307        for (i = 0; i < c->helpers.nr; i++)
 308                credential_do(c, c->helpers.items[i].string, "erase");
 309
 310        free(c->username);
 311        c->username = NULL;
 312        free(c->password);
 313        c->password = NULL;
 314        c->approved = 0;
 315}
 316
 317void credential_from_url(struct credential *c, const char *url)
 318{
 319        const char *at, *colon, *cp, *slash, *host, *proto_end;
 320
 321        credential_clear(c);
 322
 323        /*
 324         * Match one of:
 325         *   (1) proto://<host>/...
 326         *   (2) proto://<user>@<host>/...
 327         *   (3) proto://<user>:<pass>@<host>/...
 328         */
 329        proto_end = strstr(url, "://");
 330        if (!proto_end)
 331                return;
 332        cp = proto_end + 3;
 333        at = strchr(cp, '@');
 334        colon = strchr(cp, ':');
 335        slash = strchrnul(cp, '/');
 336
 337        if (!at || slash <= at) {
 338                /* Case (1) */
 339                host = cp;
 340        }
 341        else if (!colon || at <= colon) {
 342                /* Case (2) */
 343                c->username = url_decode_mem(cp, at - cp);
 344                host = at + 1;
 345        } else {
 346                /* Case (3) */
 347                c->username = url_decode_mem(cp, colon - cp);
 348                c->password = url_decode_mem(colon + 1, at - (colon + 1));
 349                host = at + 1;
 350        }
 351
 352        if (proto_end - url > 0)
 353                c->protocol = xmemdupz(url, proto_end - url);
 354        if (slash - host > 0)
 355                c->host = url_decode_mem(host, slash - host);
 356        /* Trim leading and trailing slashes from path */
 357        while (*slash == '/')
 358                slash++;
 359        if (*slash) {
 360                char *p;
 361                c->path = url_decode(slash);
 362                p = c->path + strlen(c->path) - 1;
 363                while (p > c->path && *p == '/')
 364                        *p-- = '\0';
 365        }
 366}