ngx_mail_auth_http_module.c

Nginx是一个高性能的HTTP和反向代理服务器

/*
 * Copyright (C) Igor Sysoev
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
#include <ngx_event_connect.h>
#include <ngx_mail.h>


typedef struct {
    ngx_peer_addr_t                *peer;

    ngx_msec_t                      timeout;

    ngx_str_t                       host_header;
    ngx_str_t                       uri;
    ngx_str_t                       header;

    ngx_array_t                    *headers;

    u_char                         *file;
    ngx_uint_t                      line;
} ngx_mail_auth_http_conf_t;


typedef struct ngx_mail_auth_http_ctx_s  ngx_mail_auth_http_ctx_t;

typedef void (*ngx_mail_auth_http_handler_pt)(ngx_mail_session_t *s,
    ngx_mail_auth_http_ctx_t *ctx);

struct ngx_mail_auth_http_ctx_s {
    ngx_buf_t                      *request;
    ngx_buf_t                      *response;
    ngx_peer_connection_t           peer;

    ngx_mail_auth_http_handler_pt   handler;

    ngx_uint_t                      state;
    ngx_uint_t                      hash;   /* no needed ? */

    u_char                         *header_name_start;
    u_char                         *header_name_end;
    u_char                         *header_start;
    u_char                         *header_end;

    ngx_str_t                       addr;
    ngx_str_t                       port;
    ngx_str_t                       err;
    ngx_str_t                       errmsg;
    ngx_str_t                       errcode;

    time_t                          sleep;

    ngx_pool_t                     *pool;
};


static void ngx_mail_auth_http_write_handler(ngx_event_t *wev);
static void ngx_mail_auth_http_read_handler(ngx_event_t *rev);
static void ngx_mail_auth_http_ignore_status_line(ngx_mail_session_t *s,
    ngx_mail_auth_http_ctx_t *ctx);
static void ngx_mail_auth_http_process_headers(ngx_mail_session_t *s,
    ngx_mail_auth_http_ctx_t *ctx);
static void ngx_mail_auth_sleep_handler(ngx_event_t *rev);
static ngx_int_t ngx_mail_auth_http_parse_header_line(ngx_mail_session_t *s,
    ngx_mail_auth_http_ctx_t *ctx);
static void ngx_mail_auth_http_block_read(ngx_event_t *rev);
static void ngx_mail_auth_http_dummy_handler(ngx_event_t *ev);
static ngx_buf_t *ngx_mail_auth_http_create_request(ngx_mail_session_t *s,
    ngx_pool_t *pool, ngx_mail_auth_http_conf_t *ahcf);
static ngx_int_t ngx_mail_auth_http_escape(ngx_pool_t *pool, ngx_str_t *text,
    ngx_str_t *escaped);

static void *ngx_mail_auth_http_create_conf(ngx_conf_t *cf);
static char *ngx_mail_auth_http_merge_conf(ngx_conf_t *cf, void *parent,
    void *child);
static char *ngx_mail_auth_http(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
static char *ngx_mail_auth_http_header(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);


static ngx_command_t  ngx_mail_auth_http_commands[] = {

    { ngx_string("auth_http"),
      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
      ngx_mail_auth_http,
      NGX_MAIL_SRV_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("auth_http_timeout"),
      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_msec_slot,
      NGX_MAIL_SRV_CONF_OFFSET,
      offsetof(ngx_mail_auth_http_conf_t, timeout),
      NULL },

    { ngx_string("auth_http_header"),
      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE2,
      ngx_mail_auth_http_header,
      NGX_MAIL_SRV_CONF_OFFSET,
      0,
      NULL },

      ngx_null_command
};


static ngx_mail_module_t  ngx_mail_auth_http_module_ctx = {
    NULL,                                  /* protocol */

    NULL,                                  /* create main configuration */
    NULL,                                  /* init main configuration */

    ngx_mail_auth_http_create_conf,        /* create server configuration */
    ngx_mail_auth_http_merge_conf          /* merge server configuration */
};


ngx_module_t  ngx_mail_auth_http_module = {
    NGX_MODULE_V1,
    &ngx_mail_auth_http_module_ctx,        /* module context */
    ngx_mail_auth_http_commands,           /* module directives */
    NGX_MAIL_MODULE,                       /* module type */
    NULL,                                  /* init master */
    NULL,                                  /* init module */
    NULL,                                  /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    NULL,                                  /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


static ngx_str_t   ngx_mail_auth_http_method[] = {
    ngx_string("plain"),
    ngx_string("plain"),
    ngx_string("apop"),
    ngx_string("cram-md5")
};

static ngx_str_t   ngx_mail_smtp_errcode = ngx_string("535 5.7.0");


void
ngx_mail_auth_http_init(ngx_mail_session_t *s)
{
    ngx_int_t                   rc;
    ngx_pool_t                 *pool;
    ngx_mail_auth_http_ctx_t   *ctx;
    ngx_mail_auth_http_conf_t  *ahcf;

    s->connection->log->action = "in http auth state";

    pool = ngx_create_pool(2048, s->connection->log);
    if (pool == NULL) {
        ngx_mail_session_internal_server_error(s);
        return;
    }

    ctx = ngx_pcalloc(pool, sizeof(ngx_mail_auth_http_ctx_t));
    if (ctx == NULL) {
        ngx_destroy_pool(pool);
        ngx_mail_session_internal_server_error(s);
        return;
    }

    ctx->pool = pool;

    ahcf = ngx_mail_get_module_srv_conf(s, ngx_mail_auth_http_module);

    ctx->request = ngx_mail_auth_http_create_request(s, pool, ahcf);
    if (ctx->request == NULL) {
        ngx_destroy_pool(ctx->pool);
        ngx_mail_session_internal_server_error(s);
        return;
    }

    ngx_mail_set_ctx(s, ctx, ngx_mail_auth_http_module);

    ctx->peer.sockaddr = ahcf->peer->sockaddr;
    ctx->peer.socklen = ahcf->peer->socklen;
    ctx->peer.name = &ahcf->peer->name;
    ctx->peer.get = ngx_event_get_peer;
    ctx->peer.log = s->connection->log;
    ctx->peer.log_error = NGX_ERROR_ERR;

    rc = ngx_event_connect_peer(&ctx->peer);

    if (rc == NGX_ERROR || rc == NGX_BUSY || rc == NGX_DECLINED) {
        if (ctx->peer.connection) {
            ngx_close_connection(ctx->peer.connection);
        }

        ngx_destroy_pool(ctx->pool);
        ngx_mail_session_internal_server_error(s);
        return;
    }

    ctx->peer.connection->data = s;
    ctx->peer.connection->pool = s->connection->pool;

    s->connection->read->handler = ngx_mail_auth_http_block_read;
    ctx->peer.connection->read->handler = ngx_mail_auth_http_read_handler;
    ctx->peer.connection->write->handler = ngx_mail_auth_http_write_handler;

    ctx->handler = ngx_mail_auth_http_ignore_status_line;

    ngx_add_timer(ctx->peer.connection->read, ahcf->timeout);
    ngx_add_timer(ctx->peer.connection->write, ahcf->timeout);

    if (rc == NGX_OK) {
        ngx_mail_auth_http_write_handler(ctx->peer.connection->write);
        return;
    }
}


static void
ngx_mail_auth_http_write_handler(ngx_event_t *wev)
{
    ssize_t                     n, size;
    ngx_connection_t           *c;
    ngx_mail_session_t         *s;
    ngx_mail_auth_http_ctx_t   *ctx;
    ngx_mail_auth_http_conf_t  *ahcf;

    c = wev->data;
    s = c->data;

    ctx = ngx_mail_get_module_ctx(s, ngx_mail_auth_http_module);

    ngx_log_debug0(NGX_LOG_DEBUG_MAIL, wev->log, 0,
                   "mail auth http write handler");

    if (wev->timedout) {
        ngx_log_error(NGX_LOG_ERR, wev->log, NGX_ETIMEDOUT,
                      "auth http server %V timed out", ctx->peer.name);
        ngx_close_connection(c);
        ngx_destroy_pool(ctx->pool);
        ngx_mail_session_internal_server_error(s);
        return;
    }

    size = ctx->request->last - ctx->request->pos;

    n = ngx_send(c, ctx->request->pos, size);

    if (n == NGX_ERROR) {
        ngx_close_connection(c);
        ngx_destroy_pool(ctx->pool);
        ngx_mail_session_internal_server_error(s);
        return;
    }

    if (n > 0) {
        ctx->request->pos += n;

        if (n == size) {
            wev->handler = ngx_mail_auth_http_dummy_handler;

            if (wev->timer_set) {
                ngx_del_timer(wev);
            }

            if (ngx_handle_write_event(wev, 0) == NGX_ERROR) {
                ngx_close_connection(c);
                ngx_destroy_pool(ctx->pool);
                ngx_mail_session_internal_server_error(s);
            }

            return;
        }
    }

    if (!wev->timer_set) {
        ahcf = ngx_mail_get_module_srv_conf(s, ngx_mail_auth_http_module);
        ngx_add_timer(wev, ahcf->timeout);
    }
}


static void
ngx_mail_auth_http_read_handler(ngx_event_t *rev)
{
    ssize_t                     n, size;
    ngx_connection_t          *c;
    ngx_mail_session_t        *s;
    ngx_mail_auth_http_ctx_t  *ctx;

    c = rev->data;
    s = c->data;

    ngx_log_debug0(NGX_LOG_DEBUG_MAIL, rev->log, 0,
                   "mail auth http read handler");

    ctx = ngx_mail_get_module_ctx(s, ngx_mail_auth_http_module);

    if (rev->timedout) {
        ngx_log_error(NGX_LOG_ERR, rev->log, NGX_ETIMEDOUT,
                      "auth http server %V timed out", ctx->peer.name);
        ngx_close_connection(c);
        ngx_destroy_pool(ctx->pool);
        ngx_mail_session_internal_server_error(s);
        return;
    }

    if (ctx->response == NULL) {
        ctx->response = ngx_create_temp_buf(ctx->pool, 1024);
        if (ctx->response == NULL) {
            ngx_close_connection(c);
            ngx_destroy_pool(ctx->pool);
            ngx_mail_session_internal_server_error(s);
            return;
        }
    }

    size = ctx->response->end - ctx->response->last;

    n = ngx_recv(c, ctx->response->pos, size);

    if (n > 0) {
        ctx->response->last += n;

        ctx->handler(s, ctx);
        return;
    }

    if (n == NGX_AGAIN) {
        return;
    }

    ngx_close_connection(c);
    ngx_destroy_pool(ctx->pool);
    ngx_mail_session_internal_server_error(s);
}


static void
ngx_mail_auth_http_ignore_status_line(ngx_mail_session_t *s,
    ngx_mail_auth_http_ctx_t *ctx)
{
    u_char  *p, ch;
    enum  {
        sw_start = 0,
        sw_H,
        sw_HT,
        sw_HTT,
        sw_HTTP,
        sw_skip,
        sw_almost_done
    } state;

    ngx_log_debug0(NGX_LOG_DEBUG_MAIL, s->connection->log, 0,
                   "mail auth http process status line");

    state = ctx->state;

    for (p = ctx->response->pos; p < ctx->response->last; p++) {
        ch = *p;

        switch (state) {

        /* "HTTP/" */
        case sw_start:
            if (ch == 'H') {
                state = sw_H;
                break;
            }
            goto next;

        case sw_H:
            if (ch == 'T') {
                state = sw_HT;
                break;
            }
            goto next;

        case sw_HT:
            if (ch == 'T') {
                state = sw_HTT;
                break;
            }
            goto next;

        case sw_HTT:
            if (ch == 'P') {
                state = sw_HTTP;
                break;
            }
            goto next;

        case sw_HTTP:
            if (ch == '/') {
                state = sw_skip;
                break;
            }
            goto next;

        /* any text until end of line */
        case sw_skip:
            switch (ch) {
            case CR:
                state = sw_almost_done;

                break;
            case LF:
                goto done;
            }
            break;

        /* end of status line */
        case sw_almost_done:
            if (ch == LF) {
                goto done;
            }

            ngx_log_error(NGX_LOG_ERR, s->connection->log, 0,
                          "auth http server &V sent invalid response",
                          ctx->peer.name);
            ngx_close_connection(ctx->peer.connection);
            ngx_destroy_pool(ctx->pool);
            ngx_mail_session_internal_server_error(s);
            return;
        }
    }

    ctx->response->pos = p;
    ctx->state = state;

    return;

next:

    p = ctx->response->start - 1;

done:

    ctx->response->pos = p + 1;
    ctx->state = 0;
    ctx->handler = ngx_mail_auth_http_process_headers;
    ctx->handler(s, ctx);
}


static void
ngx_mail_auth_http_process_headers(ngx_mail_session_t *s,
    ngx_mail_auth_http_ctx_t *ctx)
{
    u_char              *p;
    time_t               timer;
    size_t               len, size;
    ngx_int_t            rc, port, n;
    ngx_peer_addr_t     *peer;
    struct sockaddr_in  *sin;

    ngx_log_debug0(NGX_LOG_DEBUG_MAIL, s->connection->log, 0,
                   "mail auth http process headers");

    for ( ;; ) {
        rc = ngx_mail_auth_http_parse_header_line(s, ctx);

        if (rc == NGX_OK) {

#if (NGX_DEBUG)
            {
            ngx_str_t  key, value;

            key.len = ctx->header_name_end - ctx->header_name_start;