Andrew's git / gitweb.git / credential.c
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credential.con commit t0300: work around bug in dash 0.5.6 (78ed1d2)
   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        key = skip_prefix(var, "credential.");
  44        if (!key)
  45                return 0;
  46
  47        if (!value)
  48                return config_error_nonbool(var);
  49
  50        dot = strrchr(key, '.');
  51        if (dot) {
  52                struct credential want = CREDENTIAL_INIT;
  53                char *url = xmemdupz(key, dot - key);
  54                int matched;
  55
  56                credential_from_url(&want, url);
  57                matched = credential_match(&want, c);
  58
  59                credential_clear(&want);
  60                free(url);
  61
  62                if (!matched)
  63                        return 0;
  64                key = dot + 1;
  65        }
  66
  67        if (!strcmp(key, "helper"))
  68                string_list_append(&c->helpers, value);
  69        else if (!strcmp(key, "username")) {
  70                if (!c->username)
  71                        c->username = xstrdup(value);
  72        }
  73        else if (!strcmp(key, "usehttppath"))
  74                c->use_http_path = git_config_bool(var, value);
  75
  76        return 0;
  77}
  78
  79static int proto_is_http(const char *s)
  80{
  81        if (!s)
  82                return 0;
  83        return !strcmp(s, "https") || !strcmp(s, "http");
  84}
  85
  86static void credential_apply_config(struct credential *c)
  87{
  88        if (c->configured)
  89                return;
  90        git_config(credential_config_callback, c);
  91        c->configured = 1;
  92
  93        if (!c->use_http_path && proto_is_http(c->protocol)) {
  94                free(c->path);
  95                c->path = NULL;
  96        }
  97}
  98
  99static void credential_describe(struct credential *c, struct strbuf *out)
 100{
 101        if (!c->protocol)
 102                return;
 103        strbuf_addf(out, "%s://", c->protocol);
 104        if (c->username && *c->username)
 105                strbuf_addf(out, "%s@", c->username);
 106        if (c->host)
 107                strbuf_addstr(out, c->host);
 108        if (c->path)
 109                strbuf_addf(out, "/%s", c->path);
 110}
 111
 112static char *credential_ask_one(const char *what, struct credential *c,
 113                                int flags)
 114{
 115        struct strbuf desc = STRBUF_INIT;
 116        struct strbuf prompt = STRBUF_INIT;
 117        char *r;
 118
 119        credential_describe(c, &desc);
 120        if (desc.len)
 121                strbuf_addf(&prompt, "%s for '%s': ", what, desc.buf);
 122        else
 123                strbuf_addf(&prompt, "%s: ", what);
 124
 125        r = git_prompt(prompt.buf, flags);
 126
 127        strbuf_release(&desc);
 128        strbuf_release(&prompt);
 129        return xstrdup(r);
 130}
 131
 132static void credential_getpass(struct credential *c)
 133{
 134        if (!c->username)
 135                c->username = credential_ask_one("Username", c,
 136                                                 PROMPT_ASKPASS|PROMPT_ECHO);
 137        if (!c->password)
 138                c->password = credential_ask_one("Password", c,
 139                                                 PROMPT_ASKPASS);
 140}
 141
 142int credential_read(struct credential *c, FILE *fp)
 143{
 144        struct strbuf line = STRBUF_INIT;
 145
 146        while (strbuf_getline(&line, fp, '\n') != EOF) {
 147                char *key = line.buf;
 148                char *value = strchr(key, '=');
 149
 150                if (!line.len)
 151                        break;
 152
 153                if (!value) {
 154                        warning("invalid credential line: %s", key);
 155                        strbuf_release(&line);
 156                        return -1;
 157                }
 158                *value++ = '\0';
 159
 160                if (!strcmp(key, "username")) {
 161                        free(c->username);
 162                        c->username = xstrdup(value);
 163                } else if (!strcmp(key, "password")) {
 164                        free(c->password);
 165                        c->password = xstrdup(value);
 166                } else if (!strcmp(key, "protocol")) {
 167                        free(c->protocol);
 168                        c->protocol = xstrdup(value);
 169                } else if (!strcmp(key, "host")) {
 170                        free(c->host);
 171                        c->host = xstrdup(value);
 172                } else if (!strcmp(key, "path")) {
 173                        free(c->path);
 174                        c->path = xstrdup(value);
 175                }
 176                /*
 177                 * Ignore other lines; we don't know what they mean, but
 178                 * this future-proofs us when later versions of git do
 179                 * learn new lines, and the helpers are updated to match.
 180                 */
 181        }
 182
 183        strbuf_release(&line);
 184        return 0;
 185}
 186
 187static void credential_write_item(FILE *fp, const char *key, const char *value)
 188{
 189        if (!value)
 190                return;
 191        fprintf(fp, "%s=%s\n", key, value);
 192}
 193
 194static void credential_write(const struct credential *c, FILE *fp)
 195{
 196        credential_write_item(fp, "protocol", c->protocol);
 197        credential_write_item(fp, "host", c->host);
 198        credential_write_item(fp, "path", c->path);
 199        credential_write_item(fp, "username", c->username);
 200        credential_write_item(fp, "password", c->password);
 201}
 202
 203static int run_credential_helper(struct credential *c,
 204                                 const char *cmd,
 205                                 int want_output)
 206{
 207        struct child_process helper;
 208        const char *argv[] = { NULL, NULL };
 209        FILE *fp;
 210
 211        memset(&helper, 0, sizeof(helper));
 212        argv[0] = cmd;
 213        helper.argv = argv;
 214        helper.use_shell = 1;
 215        helper.in = -1;
 216        if (want_output)
 217                helper.out = -1;
 218        else
 219                helper.no_stdout = 1;
 220
 221        if (start_command(&helper) < 0)
 222                return -1;
 223
 224        fp = xfdopen(helper.in, "w");
 225        credential_write(c, fp);
 226        fclose(fp);
 227
 228        if (want_output) {
 229                int r;
 230                fp = xfdopen(helper.out, "r");
 231                r = credential_read(c, fp);
 232                fclose(fp);
 233                if (r < 0) {
 234                        finish_command(&helper);
 235                        return -1;
 236                }
 237        }
 238
 239        if (finish_command(&helper))
 240                return -1;
 241        return 0;
 242}
 243
 244static int credential_do(struct credential *c, const char *helper,
 245                         const char *operation)
 246{
 247        struct strbuf cmd = STRBUF_INIT;
 248        int r;
 249
 250        if (helper[0] == '!')
 251                strbuf_addstr(&cmd, helper + 1);
 252        else if (is_absolute_path(helper))
 253                strbuf_addstr(&cmd, helper);
 254        else
 255                strbuf_addf(&cmd, "git credential-%s", helper);
 256
 257        strbuf_addf(&cmd, " %s", operation);
 258        r = run_credential_helper(c, cmd.buf, !strcmp(operation, "get"));
 259
 260        strbuf_release(&cmd);
 261        return r;
 262}
 263
 264void credential_fill(struct credential *c)
 265{
 266        int i;
 267
 268        if (c->username && c->password)
 269                return;
 270
 271        credential_apply_config(c);
 272
 273        for (i = 0; i < c->helpers.nr; i++) {
 274                credential_do(c, c->helpers.items[i].string, "get");
 275                if (c->username && c->password)
 276                        return;
 277        }
 278
 279        credential_getpass(c);
 280        if (!c->username && !c->password)
 281                die("unable to get password from user");
 282}
 283
 284void credential_approve(struct credential *c)
 285{
 286        int i;
 287
 288        if (c->approved)
 289                return;
 290        if (!c->username || !c->password)
 291                return;
 292
 293        credential_apply_config(c);
 294
 295        for (i = 0; i < c->helpers.nr; i++)
 296                credential_do(c, c->helpers.items[i].string, "store");
 297        c->approved = 1;
 298}
 299
 300void credential_reject(struct credential *c)
 301{
 302        int i;
 303
 304        credential_apply_config(c);
 305
 306        for (i = 0; i < c->helpers.nr; i++)
 307                credential_do(c, c->helpers.items[i].string, "erase");
 308
 309        free(c->username);
 310        c->username = NULL;
 311        free(c->password);
 312        c->password = NULL;
 313        c->approved = 0;
 314}
 315
 316void credential_from_url(struct credential *c, const char *url)
 317{
 318        const char *at, *colon, *cp, *slash, *host, *proto_end;
 319
 320        credential_clear(c);
 321
 322        /*
 323         * Match one of:
 324         *   (1) proto://<host>/...
 325         *   (2) proto://<user>@<host>/...
 326         *   (3) proto://<user>:<pass>@<host>/...
 327         */
 328        proto_end = strstr(url, "://");
 329        if (!proto_end)
 330                return;
 331        cp = proto_end + 3;
 332        at = strchr(cp, '@');
 333        colon = strchr(cp, ':');
 334        slash = strchrnul(cp, '/');
 335
 336        if (!at || slash <= at) {
 337                /* Case (1) */
 338                host = cp;
 339        }
 340        else if (!colon || at <= colon) {
 341                /* Case (2) */
 342                c->username = url_decode_mem(cp, at - cp);
 343                host = at + 1;
 344        } else {
 345                /* Case (3) */
 346                c->username = url_decode_mem(cp, colon - cp);
 347                c->password = url_decode_mem(colon + 1, at - (colon + 1));
 348                host = at + 1;
 349        }
 350
 351        if (proto_end - url > 0)
 352                c->protocol = xmemdupz(url, proto_end - url);
 353        if (slash - host > 0)
 354                c->host = url_decode_mem(host, slash - host);
 355        /* Trim leading and trailing slashes from path */
 356        while (*slash == '/')
 357                slash++;
 358        if (*slash) {
 359                char *p;
 360                c->path = url_decode(slash);
 361                p = c->path + strlen(c->path) - 1;
 362                while (p > c->path && *p == '/')
 363                        *p-- = '\0';
 364        }
 365}