Mercurial > hg > nginx-quic
view src/mail/ngx_mail_imap_module.c @ 4964:2464ccebdb52
Upstream: fixed SIGSEGV with the "if" directive.
Configuration like
location / {
set $true 1;
if ($true) {
proxy_pass http://backend;
}
if ($true) {
# nothing
}
}
resulted in segmentation fault due to NULL pointer dereference as the
upstream configuration wasn't initialized in an implicit location created
by the last if(), but the r->content_handler was set due to first if().
Instead of committing a suicide by dereferencing a NULL pointer, return
500 (Internal Server Error) in such cases, i.e. if uscf is NULL. Better
fix would be to avoid such cases by fixing the "if" directive handling,
but it's out of scope of this patch.
Prodded by Piotr Sikora.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 13 Dec 2012 16:05:59 +0000 |
parents | d620f497c50f |
children | ec01b1d1fff1 |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #include <ngx_mail.h> #include <ngx_mail_imap_module.h> static void *ngx_mail_imap_create_srv_conf(ngx_conf_t *cf); static char *ngx_mail_imap_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child); static ngx_str_t ngx_mail_imap_default_capabilities[] = { ngx_string("IMAP4"), ngx_string("IMAP4rev1"), ngx_string("UIDPLUS"), ngx_null_string }; static ngx_conf_bitmask_t ngx_mail_imap_auth_methods[] = { { ngx_string("plain"), NGX_MAIL_AUTH_PLAIN_ENABLED }, { ngx_string("login"), NGX_MAIL_AUTH_LOGIN_ENABLED }, { ngx_string("cram-md5"), NGX_MAIL_AUTH_CRAM_MD5_ENABLED }, { ngx_null_string, 0 } }; static ngx_str_t ngx_mail_imap_auth_methods_names[] = { ngx_string("AUTH=PLAIN"), ngx_string("AUTH=LOGIN"), ngx_null_string, /* APOP */ ngx_string("AUTH=CRAM-MD5"), ngx_null_string /* NONE */ }; static ngx_mail_protocol_t ngx_mail_imap_protocol = { ngx_string("imap"), { 143, 993, 0, 0 }, NGX_MAIL_IMAP_PROTOCOL, ngx_mail_imap_init_session, ngx_mail_imap_init_protocol, ngx_mail_imap_parse_command, ngx_mail_imap_auth_state, ngx_string("* BAD internal server error" CRLF) }; static ngx_command_t ngx_mail_imap_commands[] = { { ngx_string("imap_client_buffer"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1, ngx_conf_set_size_slot, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_imap_srv_conf_t, client_buffer_size), NULL }, { ngx_string("imap_capabilities"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE, ngx_mail_capabilities, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_imap_srv_conf_t, capabilities), NULL }, { ngx_string("imap_auth"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE, ngx_conf_set_bitmask_slot, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_imap_srv_conf_t, auth_methods), &ngx_mail_imap_auth_methods }, ngx_null_command }; static ngx_mail_module_t ngx_mail_imap_module_ctx = { &ngx_mail_imap_protocol, /* protocol */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_mail_imap_create_srv_conf, /* create server configuration */ ngx_mail_imap_merge_srv_conf /* merge server configuration */ }; ngx_module_t ngx_mail_imap_module = { NGX_MODULE_V1, &ngx_mail_imap_module_ctx, /* module context */ ngx_mail_imap_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 void * ngx_mail_imap_create_srv_conf(ngx_conf_t *cf) { ngx_mail_imap_srv_conf_t *iscf; iscf = ngx_pcalloc(cf->pool, sizeof(ngx_mail_imap_srv_conf_t)); if (iscf == NULL) { return NULL; } iscf->client_buffer_size = NGX_CONF_UNSET_SIZE; if (ngx_array_init(&iscf->capabilities, cf->pool, 4, sizeof(ngx_str_t)) != NGX_OK) { return NULL; } return iscf; } static char * ngx_mail_imap_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_mail_imap_srv_conf_t *prev = parent; ngx_mail_imap_srv_conf_t *conf = child; u_char *p, *auth; size_t size; ngx_str_t *c, *d; ngx_uint_t i, m; ngx_conf_merge_size_value(conf->client_buffer_size, prev->client_buffer_size, (size_t) ngx_pagesize); ngx_conf_merge_bitmask_value(conf->auth_methods, prev->auth_methods, (NGX_CONF_BITMASK_SET |NGX_MAIL_AUTH_PLAIN_ENABLED)); if (conf->capabilities.nelts == 0) { conf->capabilities = prev->capabilities; } if (conf->capabilities.nelts == 0) { for (d = ngx_mail_imap_default_capabilities; d->len; d++) { c = ngx_array_push(&conf->capabilities); if (c == NULL) { return NGX_CONF_ERROR; } *c = *d; } } size = sizeof("* CAPABILITY" CRLF) - 1; c = conf->capabilities.elts; for (i = 0; i < conf->capabilities.nelts; i++) { size += 1 + c[i].len; } for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0; m <= NGX_MAIL_AUTH_CRAM_MD5_ENABLED; m <<= 1, i++) { if (m & conf->auth_methods) { size += 1 + ngx_mail_imap_auth_methods_names[i].len; } } p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->capability.len = size; conf->capability.data = p; p = ngx_cpymem(p, "* CAPABILITY", sizeof("* CAPABILITY") - 1); for (i = 0; i < conf->capabilities.nelts; i++) { *p++ = ' '; p = ngx_cpymem(p, c[i].data, c[i].len); } auth = p; for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0; m <= NGX_MAIL_AUTH_CRAM_MD5_ENABLED; m <<= 1, i++) { if (m & conf->auth_methods) { *p++ = ' '; p = ngx_cpymem(p, ngx_mail_imap_auth_methods_names[i].data, ngx_mail_imap_auth_methods_names[i].len); } } *p++ = CR; *p = LF; size += sizeof(" STARTTLS") - 1; p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->starttls_capability.len = size; conf->starttls_capability.data = p; p = ngx_cpymem(p, conf->capability.data, conf->capability.len - (sizeof(CRLF) - 1)); p = ngx_cpymem(p, " STARTTLS", sizeof(" STARTTLS") - 1); *p++ = CR; *p = LF; size = (auth - conf->capability.data) + sizeof(CRLF) - 1 + sizeof(" STARTTLS LOGINDISABLED") - 1; p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->starttls_only_capability.len = size; conf->starttls_only_capability.data = p; p = ngx_cpymem(p, conf->capability.data, auth - conf->capability.data); p = ngx_cpymem(p, " STARTTLS LOGINDISABLED", sizeof(" STARTTLS LOGINDISABLED") - 1); *p++ = CR; *p = LF; return NGX_CONF_OK; }