diff options
Diffstat (limited to 'src/mail/ngx_mail_imap_handler.c')
-rw-r--r-- | src/mail/ngx_mail_imap_handler.c | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/src/mail/ngx_mail_imap_handler.c b/src/mail/ngx_mail_imap_handler.c new file mode 100644 index 000000000..bf3468273 --- /dev/null +++ b/src/mail/ngx_mail_imap_handler.c @@ -0,0 +1,492 @@ + +/* + * Copyright (C) Igor Sysoev + */ + + +#include <ngx_config.h> +#include <ngx_core.h> +#include <ngx_event.h> +#include <ngx_mail.h> + + +static ngx_int_t ngx_mail_imap_login(ngx_mail_session_t *s, + ngx_connection_t *c); +static ngx_int_t ngx_mail_imap_authenticate(ngx_mail_session_t *s, + ngx_connection_t *c); +static ngx_int_t ngx_mail_imap_capability(ngx_mail_session_t *s, + ngx_connection_t *c); +static ngx_int_t ngx_mail_imap_starttls(ngx_mail_session_t *s, + ngx_connection_t *c); + + +static u_char imap_greeting[] = "* OK IMAP4 ready" CRLF; +static u_char imap_star[] = "* "; +static u_char imap_ok[] = "OK completed" CRLF; +static u_char imap_next[] = "+ OK" CRLF; +static u_char imap_plain_next[] = "+ " CRLF; +static u_char imap_username[] = "+ VXNlcm5hbWU6" CRLF; +static u_char imap_password[] = "+ UGFzc3dvcmQ6" CRLF; +static u_char imap_bye[] = "* BYE" CRLF; +static u_char imap_invalid_command[] = "BAD invalid command" CRLF; + + +void +ngx_mail_imap_init_session(ngx_mail_session_t *s, ngx_connection_t *c) +{ + ngx_mail_core_srv_conf_t *cscf; + + cscf = ngx_mail_get_module_srv_conf(s, ngx_mail_core_module); + + if (cscf->imap_auth_methods & NGX_MAIL_AUTH_CRAM_MD5_ENABLED) { + if (ngx_mail_salt(s, c, cscf) != NGX_OK) { + ngx_mail_session_internal_server_error(s); + return; + } + } + + c->read->handler = ngx_mail_imap_init_protocol; + + s->out.len = sizeof(imap_greeting) - 1; + s->out.data = imap_greeting; + + ngx_mail_send(c->write); +} + + +void +ngx_mail_imap_init_protocol(ngx_event_t *rev) +{ + ngx_connection_t *c; + ngx_mail_session_t *s; + ngx_mail_core_srv_conf_t *cscf; + + c = rev->data; + + c->log->action = "in auth state"; + + if (rev->timedout) { + ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out"); + c->timedout = 1; + ngx_mail_close_connection(c); + return; + } + + s = c->data; + + if (s->buffer == NULL) { + if (ngx_array_init(&s->args, c->pool, 2, sizeof(ngx_str_t)) + == NGX_ERROR) + { + ngx_mail_session_internal_server_error(s); + return; + } + + cscf = ngx_mail_get_module_srv_conf(s, ngx_mail_core_module); + + s->buffer = ngx_create_temp_buf(c->pool, cscf->imap_client_buffer_size); + if (s->buffer == NULL) { + ngx_mail_session_internal_server_error(s); + return; + } + } + + s->mail_state = ngx_imap_start; + c->read->handler = ngx_imap_auth_state; + + ngx_imap_auth_state(rev); +} + + +void +ngx_imap_auth_state(ngx_event_t *rev) +{ + u_char *p, *dst, *src, *end; + ngx_str_t *arg; + ngx_int_t rc; + ngx_uint_t tag, i; + ngx_connection_t *c; + ngx_mail_session_t *s; + + c = rev->data; + s = c->data; + + ngx_log_debug0(NGX_LOG_DEBUG_MAIL, c->log, 0, "imap auth state"); + + if (rev->timedout) { + ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out"); + c->timedout = 1; + ngx_mail_close_connection(c); + return; + } + + if (s->out.len) { + ngx_log_debug0(NGX_LOG_DEBUG_MAIL, c->log, 0, "imap send handler busy"); + s->blocked = 1; + return; + } + + s->blocked = 0; + + rc = ngx_mail_read_command(s); + + if (rc == NGX_AGAIN || rc == NGX_ERROR) { + return; + } + + tag = 1; + s->text.len = 0; + s->out.len = sizeof(imap_ok) - 1; + s->out.data = imap_ok; + + if (rc == NGX_OK) { + + ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0, "imap auth command: %i", + s->command); + + if (s->backslash) { + + arg = s->args.elts; + + for (i = 0; i < s->args.nelts; i++) { + dst = arg[i].data; + end = dst + arg[i].len; + + for (src = dst; src < end; dst++) { + *dst = *src; + if (*src++ == '\\') { + *dst = *src++; + } + } + + arg[i].len = dst - arg[i].data; + } + + s->backslash = 0; + } + + switch (s->mail_state) { + + case ngx_imap_start: + + switch (s->command) { + + case NGX_IMAP_LOGIN: + rc = ngx_mail_imap_login(s, c); + break; + + case NGX_IMAP_AUTHENTICATE: + rc = ngx_mail_imap_authenticate(s, c); + + if (rc == NGX_OK) { + tag = 0; + } + + break; + + case NGX_IMAP_CAPABILITY: + rc = ngx_mail_imap_capability(s, c); + break; + + case NGX_IMAP_LOGOUT: + s->quit = 1; + s->text.len = sizeof(imap_bye) - 1; + s->text.data = imap_bye; + break; + + case NGX_IMAP_NOOP: + break; + + case NGX_IMAP_STARTTLS: + rc = ngx_mail_imap_starttls(s, c); + break; + + default: + rc = NGX_MAIL_PARSE_INVALID_COMMAND; + break; + } + + break; + + case ngx_imap_auth_login_username: + rc = ngx_mail_auth_login_username(s, c); + + tag = 0; + s->out.len = sizeof(imap_password) - 1; + s->out.data = imap_password; + s->mail_state = ngx_imap_auth_login_password; + + break; + + case ngx_imap_auth_login_password: + rc = ngx_mail_auth_login_password(s, c); + break; + + case ngx_imap_auth_plain: + rc = ngx_mail_auth_plain(s, c, 0); + break; + + case ngx_imap_auth_cram_md5: + rc = ngx_mail_auth_cram_md5(s, c); + break; + } + + } else if (rc == NGX_IMAP_NEXT) { + tag = 0; + s->out.len = sizeof(imap_next) - 1; + s->out.data = imap_next; + } + + switch (rc) { + + case NGX_DONE: + ngx_mail_auth(s); + return; + + case NGX_ERROR: + ngx_mail_session_internal_server_error(s); + return; + + case NGX_MAIL_PARSE_INVALID_COMMAND: + s->state = 0; + s->out.len = sizeof(imap_invalid_command) - 1; + s->out.data = imap_invalid_command; + s->mail_state = ngx_imap_start; + break; + } + + if (tag) { + if (s->tag.len == 0) { + s->tag.len = sizeof(imap_star) - 1; + s->tag.data = (u_char *) imap_star; + } + + if (s->tagged_line.len < s->tag.len + s->text.len + s->out.len) { + s->tagged_line.len = s->tag.len + s->text.len + s->out.len; + s->tagged_line.data = ngx_palloc(c->pool, s->tagged_line.len); + if (s->tagged_line.data == NULL) { + ngx_mail_close_connection(c); + return; + } + } + + p = s->tagged_line.data; + + if (s->text.len) { + p = ngx_cpymem(p, s->text.data, s->text.len); + } + + p = ngx_cpymem(p, s->tag.data, s->tag.len); + ngx_memcpy(p, s->out.data, s->out.len); + + s->out.len = s->text.len + s->tag.len + s->out.len; + s->out.data = s->tagged_line.data; + } + + if (rc != NGX_IMAP_NEXT) { + s->args.nelts = 0; + + if (s->state) { + /* preserve tag */ + s->arg_start = s->buffer->start + s->tag.len; + s->buffer->pos = s->arg_start; + s->buffer->last = s->arg_start; + + } else { + s->buffer->pos = s->buffer->start; + s->buffer->last = s->buffer->start; + s->tag.len = 0; + } + } + + ngx_mail_send(c->write); +} + + +static ngx_int_t +ngx_mail_imap_login(ngx_mail_session_t *s, ngx_connection_t *c) +{ + ngx_str_t *arg; +#if (NGX_MAIL_SSL) + ngx_mail_ssl_conf_t *sslcf; + + if (c->ssl == NULL) { + sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module); + + if (sslcf->starttls == NGX_MAIL_STARTTLS_ONLY) { + return NGX_MAIL_PARSE_INVALID_COMMAND; + } + } +#endif + + arg = s->args.elts; + + if (s->args.nelts != 2 || arg[0].len == 0) { + return NGX_MAIL_PARSE_INVALID_COMMAND; + } + + s->login.len = arg[0].len; + s->login.data = ngx_palloc(c->pool, s->login.len); + if (s->login.data == NULL) { + return NGX_ERROR; + } + + ngx_memcpy(s->login.data, arg[0].data, s->login.len); + + s->passwd.len = arg[1].len; + s->passwd.data = ngx_palloc(c->pool, s->passwd.len); + if (s->passwd.data == NULL) { + return NGX_ERROR; + } + + ngx_memcpy(s->passwd.data, arg[1].data, s->passwd.len); + +#if (NGX_DEBUG_MAIL_PASSWD) + ngx_log_debug2(NGX_LOG_DEBUG_MAIL, c->log, 0, + "imap login:\"%V\" passwd:\"%V\"", + &s->login, &s->passwd); +#else + ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0, + "imap login:\"%V\"", &s->login); +#endif + + return NGX_DONE; +} + + +static ngx_int_t +ngx_mail_imap_authenticate(ngx_mail_session_t *s, ngx_connection_t *c) +{ + u_char *p; + ngx_str_t *arg, salt; + ngx_uint_t n; + ngx_mail_core_srv_conf_t *cscf; +#if (NGX_MAIL_SSL) + ngx_mail_ssl_conf_t *sslcf; + + if (c->ssl == NULL) { + sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module); + + if (sslcf->starttls == NGX_MAIL_STARTTLS_ONLY) { + return NGX_MAIL_PARSE_INVALID_COMMAND; + } + } +#endif + + if (s->args.nelts != 1) { + return NGX_MAIL_PARSE_INVALID_COMMAND; + } + + arg = s->args.elts; + + if (arg[0].len == 5) { + + if (ngx_strncasecmp(arg[0].data, (u_char *) "LOGIN", 5) == 0) { + + s->out.len = sizeof(imap_username) - 1; + s->out.data = imap_username; + s->mail_state = ngx_imap_auth_login_username; + + return NGX_OK; + + } else if (ngx_strncasecmp(arg[0].data, (u_char *) "PLAIN", 5) == 0) { + + s->out.len = sizeof(imap_plain_next) - 1; + s->out.data = imap_plain_next; + s->mail_state = ngx_imap_auth_plain; + + return NGX_OK; + } + + } else if (arg[0].len == 8 + && ngx_strncasecmp(arg[0].data, (u_char *) "CRAM-MD5", 8) == 0) + { + if (s->args.nelts != 1) { + return NGX_MAIL_PARSE_INVALID_COMMAND; + } + + cscf = ngx_mail_get_module_srv_conf(s, ngx_mail_core_module); + + if (!(cscf->imap_auth_methods & NGX_MAIL_AUTH_CRAM_MD5_ENABLED)) { + return NGX_MAIL_PARSE_INVALID_COMMAND; + } + + p = ngx_palloc(c->pool, + sizeof("+ " CRLF) - 1 + + ngx_base64_encoded_length(s->salt.len)); + if (p == NULL) { + return NGX_ERROR; + } + + p[0] = '+'; p[1]= ' '; + salt.data = &p[2]; + s->salt.len -= 2; + + ngx_encode_base64(&salt, &s->salt); + + s->salt.len += 2; + n = 2 + salt.len; + p[n++] = CR; p[n++] = LF; + + s->out.len = n; + s->out.data = p; + s->mail_state = ngx_imap_auth_cram_md5; + + return NGX_OK; + } + + return NGX_MAIL_PARSE_INVALID_COMMAND; +} + + +static ngx_int_t +ngx_mail_imap_capability(ngx_mail_session_t *s, ngx_connection_t *c) +{ + ngx_mail_core_srv_conf_t *cscf; +#if (NGX_MAIL_SSL) + ngx_mail_ssl_conf_t *sslcf; +#endif + + cscf = ngx_mail_get_module_srv_conf(s, ngx_mail_core_module); + +#if (NGX_MAIL_SSL) + + if (c->ssl == NULL) { + sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module); + + if (sslcf->starttls == NGX_MAIL_STARTTLS_ON) { + s->text = cscf->imap_starttls_capability; + return NGX_OK; + } + + if (sslcf->starttls == NGX_MAIL_STARTTLS_ONLY) { + s->text = cscf->imap_starttls_only_capability; + return NGX_OK; + } + } +#endif + + s->text = cscf->imap_capability; + + return NGX_OK; +} + + +static ngx_int_t +ngx_mail_imap_starttls(ngx_mail_session_t *s, ngx_connection_t *c) +{ +#if (NGX_MAIL_SSL) + ngx_mail_ssl_conf_t *sslcf; + + if (c->ssl == NULL) { + sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module); + if (sslcf->starttls) { + c->read->handler = ngx_mail_starttls_handler; + return NGX_OK; + } + } + +#endif + + return NGX_MAIL_PARSE_INVALID_COMMAND; +} |