src/lib-imap/imap-id.c

/* Copyright (c) 2008-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "str.h"
#include "str-sanitize.h"
#include "istream.h"
#include "imap-parser.h"
#include "imap-quote.h"
#include "imap-id.h"

#ifdef HAVE_SYS_UTSNAME_H
#  include <sys/utsname.h>
#endif

#ifdef HAVE_UNAME
static struct utsname utsname_result;
static bool utsname_set = FALSE;

static const char *imap_id_get_uname(const char *key)
{
    if (!utsname_set) {
        utsname_set = TRUE;
        if (uname(&utsname_result) < 0) {
            i_error("uname() failed: %m");
            i_zero(&utsname_result);
        }
    }

    if (strcasecmp(key, "os") == 0)
        return utsname_result.sysname;
    if (strcasecmp(key, "os-version") == 0)
        return utsname_result.release;
    return NULL;
}
#endif

static const char *imap_id_get_default(const char *key)
{
    if (strcasecmp(key, "name") == 0)
        return PACKAGE_NAME;
    if (strcasecmp(key, "version") == 0)
        return PACKAGE_VERSION;
    if (strcasecmp(key, "support-url") == 0)
        return PACKAGE_WEBPAGE;
    if (strcasecmp(key, "support-email") == 0)
        return PACKAGE_BUGREPORT;
#ifdef HAVE_UNAME
    return imap_id_get_uname(key);
#endif
}

static const char *
imap_id_reply_generate_from_imap_args(const struct imap_arg *args)
{
    string_t *str;
    const char *key, *value;

    if (IMAP_ARG_IS_EOL(args))
        return "NIL";

    str = t_str_new(256);
    str_append_c(str, '(');
    for (; !IMAP_ARG_IS_EOL(args); args++) {
        if (!imap_arg_get_astring(args, &key)) {
            /* broken input */
            if (IMAP_ARG_IS_EOL(&args[1]))
                break;
            args++;
        } else {
            /* key */
            if (str_len(str) > 1)
                str_append_c(str, ' ');
            imap_append_quoted(str, key);
            str_append_c(str, ' ');
            /* value */
            if (IMAP_ARG_IS_EOL(&args[1])) {
                str_append(str, "NIL");
                break;
            }
            args++;
            if (!imap_arg_get_astring(args, &value))
                value = NULL;
            else {
                if (strcmp(value, "*") == 0)
                    value = imap_id_get_default(key);
            }
            imap_append_nstring(str, value);
        }
    }
    if (str_len(str) == 1) {
        /* broken */
        return "NIL";
    }
    str_append_c(str, ')');
    return str_c(str);
}

const char *imap_id_reply_generate(const char *settings)
{
    struct istream *input;
    struct imap_parser *parser;
    const struct imap_arg *args;
    const char *ret;

    if (settings == NULL)
        return "NIL";

    input = i_stream_create_from_data(settings, strlen(settings));
    (void)i_stream_read(input);

    parser = imap_parser_create(input, NULL, (size_t)-1);
    if (imap_parser_finish_line(parser, 0, 0, &args) <= 0)
        ret = "NIL";
    else
        ret = imap_id_reply_generate_from_imap_args(args);

    imap_parser_unref(&parser);
    i_stream_destroy(&input);
    return ret;
}

void imap_id_log_reply_append(string_t *reply, const char *key,
                  const char *value)
{
    if (str_len(reply) > 0)
        str_append(reply, ", ");
    str_append(reply, str_sanitize(key, IMAP_ID_KEY_MAX_LEN));
    str_append_c(reply, '=');
    str_append(reply, value == NULL ? "NIL" : str_sanitize(value, 80));
}

const char *imap_id_args_get_log_reply(const struct imap_arg *args,
                       const char *settings)
{
    const char *const *keys, *key, *value;
    string_t *reply;
    bool log_all;

    if (settings == NULL || *settings == '\0')
        return NULL;
    if (!imap_arg_get_list(args, &args))
        return NULL;

    log_all = strcmp(settings, "*") == 0;
    reply = t_str_new(256);
    keys = t_strsplit_spaces(settings, " ");
    while (!IMAP_ARG_IS_EOL(&args[0]) &&
           !IMAP_ARG_IS_EOL(&args[1])) {
        if (!imap_arg_get_string(args, &key)) {
            /* broken input */
            args += 2;
            continue;
        }
        args++;
        if (strlen(key) > 30) {
            /* broken: ID spec requires fields to be max. 30
               octets */
            args++;
            continue;
        }

        if (log_all || str_array_icase_find(keys, key)) {
            if (!imap_arg_get_nstring(args, &value))
                value = "";
            imap_id_log_reply_append(reply, key, value);
        }
        args++;
    }
    return str_len(reply) == 0 ? NULL : str_c(reply);
}