diff options
Diffstat (limited to 'src/imap/ngx_imap_proxy_module.c')
| -rw-r--r-- | src/imap/ngx_imap_proxy_module.c | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/src/imap/ngx_imap_proxy_module.c b/src/imap/ngx_imap_proxy_module.c new file mode 100644 index 000000000..b3bedae58 --- /dev/null +++ b/src/imap/ngx_imap_proxy_module.c @@ -0,0 +1,439 @@ + +/* + * Copyright (C) Igor Sysoev + */ + + +#include <ngx_config.h> +#include <ngx_core.h> +#include <ngx_event.h> +#include <ngx_event_connect.h> +#include <ngx_imap.h> + + +typedef struct { + ngx_flag_t enable; +} ngx_imap_proxy_conf_t; + + +static void ngx_imap_proxy_block_read(ngx_event_t *rev); +static void ngx_imap_proxy_auth_handler(ngx_event_t *rev); +static void ngx_imap_proxy_dummy_handler(ngx_event_t *ev); +static ngx_int_t ngx_imap_proxy_read_response(ngx_imap_session_t *s); +static void ngx_imap_proxy_handler(ngx_event_t *ev); +static void ngx_imap_proxy_close_session(ngx_imap_session_t *s); +static void *ngx_imap_proxy_create_conf(ngx_conf_t *cf); +static char *ngx_imap_proxy_merge_conf(ngx_conf_t *cf, void *parent, + void *child); + + +static ngx_command_t ngx_imap_proxy_commands[] = { + { ngx_string("proxy"), + NGX_IMAP_MAIN_CONF|NGX_IMAP_SRV_CONF|NGX_CONF_FLAG, + ngx_conf_set_flag_slot, + NGX_IMAP_SRV_CONF_OFFSET, + offsetof(ngx_imap_proxy_conf_t, enable), + NULL }, + + ngx_null_command +}; + + +static ngx_imap_module_t ngx_imap_proxy_module_ctx = { + NULL, /* create main configuration */ + NULL, /* init main configuration */ + + ngx_imap_proxy_create_conf, /* create server configuration */ + ngx_imap_proxy_merge_conf /* merge server configuration */ +}; + + +ngx_module_t ngx_imap_proxy_module = { + NGX_MODULE_V1, + &ngx_imap_proxy_module_ctx, /* module context */ + ngx_imap_proxy_commands, /* module directives */ + NGX_IMAP_MODULE, /* module type */ + NULL, /* init module */ + NULL /* init process */ +}; + + +void +ngx_imap_proxy_init(ngx_imap_session_t *s, ngx_peers_t *peers) +{ + ngx_int_t rc; + ngx_imap_proxy_ctx_t *p; + + p = ngx_pcalloc(s->connection->pool, sizeof(ngx_imap_proxy_ctx_t)); + if (p == NULL) { + ngx_imap_close_connection(s->connection); + return; + } + + s->proxy = p; + + p->upstream.peers = peers; + p->upstream.log = s->connection->log; + p->upstream.log_error = NGX_ERROR_ERR; + + rc = ngx_event_connect_peer(&p->upstream); + + if (rc == NGX_ERROR) { + ngx_imap_proxy_close_session(s); + return; + } + + p->upstream.connection->data = s; + p->upstream.connection->pool = s->connection->pool; + + s->connection->read->handler = ngx_imap_proxy_block_read; + p->upstream.connection->read->handler = ngx_imap_proxy_auth_handler; + p->upstream.connection->write->handler = ngx_imap_proxy_dummy_handler; +} + + +static void +ngx_imap_proxy_block_read(ngx_event_t *rev) +{ + ngx_connection_t *c; + ngx_imap_session_t *s; + + ngx_log_debug0(NGX_LOG_DEBUG_IMAP, rev->log, 0, "imap proxy block read"); + + if (ngx_handle_read_event(rev, 0) == NGX_ERROR) { + c = rev->data; + s = c->data; + + ngx_imap_proxy_close_session(s); + } +} + + +static void +ngx_imap_proxy_auth_handler(ngx_event_t *rev) +{ + u_char *p; + ngx_int_t rc; + ngx_str_t line; + ngx_connection_t *c; + ngx_imap_session_t *s; + + ngx_log_debug0(NGX_LOG_DEBUG_IMAP, rev->log, 0, "imap proxy auth handler"); + + c = rev->data; + s = c->data; + + if (rev->timedout) { + ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out"); + ngx_imap_proxy_close_session(s); + return; + } + + if (s->proxy->buffer == NULL) { + s->proxy->buffer = ngx_create_temp_buf(c->pool, /* STUB */ 4096); + if (s->proxy->buffer == NULL) { + ngx_imap_proxy_close_session(s); + return; + } + } + + rc = ngx_imap_proxy_read_response(s); + + if (rc == NGX_AGAIN) { + return; + } + + if (rc == NGX_ERROR) { + /* TODO: ngx_imap_proxy_finalize_session(s, NGX_IMAP_INTERNAL_ERROR) */ + ngx_imap_proxy_close_session(s); + return; + } + + if (s->imap_state == ngx_pop3_start) { + + ngx_log_debug0(NGX_LOG_DEBUG_IMAP, rev->log, 0, "imap proxy send user"); + + line.len = sizeof("USER ") + s->login.len - 1 + 2; + line.data = ngx_palloc(c->pool, line.len); + if (line.data == NULL) { + ngx_imap_proxy_close_session(s); + return; + } + + p = ngx_cpymem(line.data, "USER ", sizeof("USER ") - 1); + p = ngx_cpymem(p, s->login.data, s->login.len); + *p++ = CR; *p = LF; + + if (ngx_send(c, line.data, line.len) < (ssize_t) line.len) { + /* + * we treat the incomplete sending as NGX_ERROR + * because it is very strange here + */ + ngx_imap_close_connection(c); + return; + } + + s->imap_state = ngx_pop3_user; + + s->proxy->buffer->pos = s->proxy->buffer->start; + s->proxy->buffer->last = s->proxy->buffer->start; + + return; + } + + ngx_log_debug0(NGX_LOG_DEBUG_IMAP, rev->log, 0, "imap proxy send pass"); + + line.len = sizeof("PASS ") + s->passwd.len - 1 + 2; + line.data = ngx_palloc(c->pool, line.len); + if (line.data == NULL) { + ngx_imap_proxy_close_session(s); + return; + } + + p = ngx_cpymem(line.data, "PASS ", sizeof("PASS ") - 1); + p = ngx_cpymem(p, s->passwd.data, s->passwd.len); + *p++ = CR; *p = LF; + + if (ngx_send(c, line.data, line.len) < (ssize_t) line.len) { + /* + * we treat the incomplete sending as NGX_ERROR + * because it is very strange here + */ + ngx_imap_close_connection(c); + return; + } + + s->proxy->buffer->pos = s->proxy->buffer->start; + s->proxy->buffer->last = s->proxy->buffer->start; + + s->connection->read->handler = ngx_imap_proxy_handler; + s->connection->write->handler = ngx_imap_proxy_handler; + rev->handler = ngx_imap_proxy_handler; + c->write->handler = ngx_imap_proxy_handler; +} + + +static void +ngx_imap_proxy_dummy_handler(ngx_event_t *ev) +{ + ngx_log_debug0(NGX_LOG_DEBUG_IMAP, ev->log, 0, "imap proxy dummy handler"); +} + + +static ngx_int_t +ngx_imap_proxy_read_response(ngx_imap_session_t *s) +{ + u_char *p; + ssize_t n; + ngx_buf_t *b; + + b = s->proxy->buffer; + + n = ngx_recv(s->proxy->upstream.connection, b->last, b->end - b->last); + + if (n == NGX_ERROR || n == 0) { + return NGX_ERROR; + } + + if (n == NGX_AGAIN) { + return NGX_AGAIN; + } + + b->last += n; + + if (b->last - b->pos < 5) { + return NGX_AGAIN; + } + + if (*(b->last - 2) != CR || *(b->last - 1) != LF) { + if (b->last == b->end) { + *(b->last - 1) = '\0'; + ngx_log_error(NGX_LOG_ERR, s->connection->log, 0, + "upstream sent too long response line: \"%s\"", + b->pos); + return NGX_IMAP_PROXY_INVALID; + } + + return NGX_AGAIN; + } + + p = b->pos; + + if (p[0] == '+' && p[1] == 'O' && p[2] == 'K') { + return NGX_OK; + } + + if (p[0] == '-' && p[1] == 'E' && p[2] == 'R' && p[3] == 'R') { + return NGX_IMAP_PROXY_ERROR; + } + + *(b->last - 2) = '\0'; + ngx_log_error(NGX_LOG_ERR, s->connection->log, 0, + "upstream sent invalid greeting line: \"%s\"", p); + + return NGX_IMAP_PROXY_INVALID; +} + + +static void +ngx_imap_proxy_handler(ngx_event_t *ev) +{ + size_t size; + ssize_t n; + ngx_buf_t *b; + ngx_uint_t again, do_write; + ngx_connection_t *c, *src, *dst; + ngx_imap_session_t *s; + + c = ev->data; + s = c->data; + + if (ev->timedout) { + if (c == s->connection) { + ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, + "client timed out"); + } else { + ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, + "upstream timed out"); + } + + ngx_imap_proxy_close_session(s); + return; + } + + if (c == s->connection) { + if (ev->write) { + src = s->proxy->upstream.connection; + dst = c; + b = s->proxy->buffer; + + } else { + src = c; + dst = s->proxy->upstream.connection; + b = s->buffer; + } + + } else { + if (ev->write) { + src = s->connection; + dst = c; + b = s->buffer; + + } else { + src = c; + dst = s->connection; + b = s->proxy->buffer; + } + } + + do_write = ev->write ? 1 : 0; + + ngx_log_debug3(NGX_LOG_DEBUG_IMAP, ev->log, 0, + "imap proxy handler: %d, #%d > #%d", + do_write, src->fd, dst->fd); + + do { + again = 0; + + if (do_write == 1) { + + size = b->last - b->pos; + + if (size && dst->write->ready) { + n = ngx_send(dst, b->pos, size); + + if (n == NGX_ERROR) { + ngx_imap_proxy_close_session(s); + return; + } + + if (n > 0) { + again = 1; + b->pos += n; + + if (b->pos == b->last) { + b->pos = b->start; + b->last = b->start; + } + } + + if (n == NGX_AGAIN || n < (ssize_t) size) { + if (ngx_handle_write_event(dst->write, /* TODO: LOWAT */ 0) + == NGX_ERROR) + { + ngx_imap_proxy_close_session(s); + return; + } + } + } + } + + size = b->end - b->last; + + if (size && src->read->ready) { + n = ngx_recv(src, b->last, size); + + if (n == NGX_ERROR || n == 0) { + ngx_imap_proxy_close_session(s); + return; + } + + if (n > 0) { + again = 1; + do_write = 1; + b->last += n; + } + + if (n == NGX_AGAIN || n < (ssize_t) size) { + if (ngx_handle_read_event(src->read, 0) == NGX_ERROR) { + ngx_imap_proxy_close_session(s); + return; + } + } + } + + } while (again); +} + + +static void +ngx_imap_proxy_close_session(ngx_imap_session_t *s) +{ + if (s->proxy->upstream.connection) { + ngx_log_debug1(NGX_LOG_DEBUG_IMAP, s->connection->log, 0, + "close imap proxy connection: %d", + s->proxy->upstream.connection->fd); + + ngx_close_connection(s->proxy->upstream.connection); + } + + ngx_imap_close_connection(s->connection); +} + + +static void * +ngx_imap_proxy_create_conf(ngx_conf_t *cf) +{ + ngx_imap_proxy_conf_t *pcf; + + pcf = ngx_pcalloc(cf->pool, sizeof(ngx_imap_proxy_conf_t)); + if (pcf == NULL) { + return NGX_CONF_ERROR; + } + + pcf->enable = NGX_CONF_UNSET; + + return pcf; +} + + +static char * +ngx_imap_proxy_merge_conf(ngx_conf_t *cf, void *parent, void *child) +{ + ngx_imap_proxy_conf_t *prev = parent; + ngx_imap_proxy_conf_t *conf = child; + + ngx_conf_merge_msec_value(conf->enable, prev->enable, 0); + + return NGX_CONF_OK; +} |