diff options
Diffstat (limited to '')
| -rw-r--r-- | dirmngr/server.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/dirmngr/server.c b/dirmngr/server.c index e5cf2c3aa..22d6f2d1e 100644 --- a/dirmngr/server.c +++ b/dirmngr/server.c @@ -54,6 +54,7 @@ #include "mbox-util.h" #include "zb32.h" #include "server-help.h" +#include "../common/exectool.h" /* To avoid DoS attacks we limit the size of a certificate to something reasonable. The DoS was actually only an issue back when @@ -2340,6 +2341,231 @@ cmd_reloaddirmngr (assuan_context_t ctx, char *line) } + +/* Returns -1 if version a is less than b, 0 if the versions are equal and 1 otherwise. + * Versions are compared as period-separated tuples starting at the front. Elements are + * interpreted as decimals first. If this fails strcmp is used. Comparison continues + * until two elements are found the be unequal of the end is reached. */ +static int +cmp_version(const char* a, const char* b) +{ + char *a_dup, *b_dup, *strtok_internal_a = NULL, *strtok_internal_b = NULL, *a_comp, *b_comp; + int ret = 0; + + assert (a && b); + + a_dup = xstrdup (a); + b_dup = xstrdup (b); + a_comp = strtok_r (a_dup, ".", &strtok_internal_a); + b_comp = strtok_r (b_dup, ".", &strtok_internal_b); + + while (a_comp || b_comp) + { + if (a_comp && *a_comp && b_comp && *b_comp) + { + char* a_end; + char* b_end; + int a_ver = strtol (a_comp, &a_end, 10); + int b_ver = strtol (b_comp, &b_end, 10); + + if (!*a_end && !*b_end) + { + if (a_ver != b_ver) + { + ret = a_ver - b_ver; + break; + } + } + else + { + int r = strcmp (a_comp, b_comp); + if (r != 0) + { + ret = r; + break; + } + } + } + else + { + if ((!a_comp || !*a_comp) && b_comp && *b_comp) + ret = -1; + else if (a_comp && *a_comp && (!b_comp || !*b_comp)) + ret = 1; + else + ret = 0; + break; + } + + a_comp = strtok_r (NULL, ".", &strtok_internal_a); + b_comp = strtok_r (NULL, ".", &strtok_internal_b); + } + + xfree (a_dup); + xfree (b_dup); + return ret; +} + +static int +fetch_into_tmpfile(const char* url, ctrl_t ctrl, estream_t* strm_out, char** path) +{ + gpg_error_t err = 0; + char* filename = xmalloc (128); + int fd = -1; + estream_t file; + estream_t strm; + size_t len = 0; + char buf[1024]; + + if (!strm_out) + { + err = (GPG_ERR_INV_ARG); + goto leave; + } + + snprintf (filename ,128 ,"%s%s%s" ,P_tmpdir ,DIRSEP_S ,"dirmngr_fetch_XXXXXX"); + + if ((fd = mkstemp (filename)) < 0) + { + err = gpg_err_code_from_syserror (); + goto leave; + } + + file = es_fdopen (fd, "w+"); + + if ((err = ks_http_fetch (ctrl, url, &strm))) + goto leave; + + while (!es_read (strm, buf, 1024, &len)) + { + if (!len) + break; + if ((err = es_write (file, buf, len, NULL))) + { + log_error ("error writing message to pipe: %s\n", gpg_strerror (err)); + es_free (strm); + goto leave; + } + } + + es_rewind (file); + es_fclose (strm); + *strm_out = file; + + if (path) + { + *path = filename; + filename = NULL; + } + +leave: + if (filename) + xfree (filename); + return err; +} + +static const char hlp_versioncheck[] = + "VERSIONCHECK <name> <version>" + "\n" + "Checks the internet to find whenever a new program version is available." + "\n" + "<name> program name i.e. \"gnupg\"" + "<version> current version of the program i.e. \"2.0.2\""; +static gpg_error_t +cmd_versioncheck (assuan_context_t ctx, char *line) +{ + gpg_error_t err; + char* strtok_internal = NULL; + char* name = strtok_r (line, " ", &strtok_internal); + char* version = strtok_r (NULL, " ", &strtok_internal); + ctrl_t ctrl = assuan_get_pointer (ctx); + estream_t swdb; + estream_t swdb_sig; + char* swdb_path = NULL; + char* swdb_sig_path = NULL; + char* buf = NULL; + size_t len = 0; + const size_t name_len = (name ? strlen (name) : 0); + const size_t version_len = (version ? strlen (version) : 0); + const char *argv[8]; + char keyring_path[128]; + + if (!name || name_len == 0) + { + err = set_error (GPG_ERR_ASS_PARAMETER, "No program name given"); + goto out; + } + + if (!version || version_len == 0) + { + err = set_error (GPG_ERR_ASS_PARAMETER, "No program version given"); + goto out; + } + + if ((err = fetch_into_tmpfile ("https://versions.gnupg.org/swdb.lst", ctrl, &swdb, &swdb_path))) + goto out; + + if ((err = fetch_into_tmpfile ("https://versions.gnupg.org/swdb.lst.sig", ctrl, &swdb_sig, &swdb_sig_path))) + goto out; + + snprintf(keyring_path, 128, "%s%s%s", gnupg_datadir (), DIRSEP_S, "distsigkey.gpg"); + + argv[0] = "--batch"; + argv[1] = "--no-default-keyring"; + argv[2] = "--keyring"; + argv[3] = keyring_path; + argv[4] = "--verify"; + argv[5] = swdb_sig_path; + argv[6] = "-"; + argv[7] = NULL; + + if ((err = gnupg_exec_tool_stream(gnupg_module_name (GNUPG_MODULE_NAME_GPG), + argv, swdb, NULL, NULL, NULL, NULL))) + goto out; + + es_fseek (swdb, 0, SEEK_SET); + + while (es_getline (&buf, &len, swdb) > 0) + { + if (len > name_len + 5 && + strncmp (buf, name, name_len) == 0 && + strncmp (buf + name_len, "_ver ", 5) == 0) + { + const char* this_ver_start = buf + name_len + 5; + char* this_ver_end = strchr (this_ver_start, '\n'); + int cmp; + + if (this_ver_end) + *this_ver_end = 0; + + err = assuan_write_status (ctx, "LINE", buf); + + cmp = cmp_version(this_ver_start,version); + + if (cmp < 0) + err = assuan_send_data (ctx, "ROLLBACK", strlen ("ROLLBACK")); + else if (cmp == 0) + err = assuan_send_data (ctx, "CURRENT", strlen ("CURRENT")); + else + err = assuan_send_data (ctx, "UPDATE", strlen ("UPDATE")); + + goto out; + } + } + + err = assuan_send_data (ctx, "NOT_FOUND", strlen ("NOT_FOUND")); + + out: + es_fclose (swdb); + es_fclose (swdb_sig); + xfree(buf); + unlink(swdb_path); + unlink(swdb_sig_path); + xfree(swdb_path); + xfree(swdb_sig_path); + return leave_cmd (ctx, err); +} + /* Tell the assuan library about our commands. */ @@ -2370,6 +2596,7 @@ register_commands (assuan_context_t ctx) { "GETINFO", cmd_getinfo, hlp_getinfo }, { "KILLDIRMNGR",cmd_killdirmngr,hlp_killdirmngr }, { "RELOADDIRMNGR",cmd_reloaddirmngr,hlp_reloaddirmngr }, + { "VERSIONCHECK",cmd_versioncheck,hlp_versioncheck }, { NULL, NULL } }; int i, j, rc; |