DNS and ENUM functions. More...
#include "asterisk/channel.h"
Go to the source code of this file.
Data Structures | |
struct | enum_context |
struct | enum_naptr_rr |
struct | naptr |
Functions | |
int | ast_enum_init (void) |
int | ast_enum_reload (void) |
int | ast_get_enum (struct ast_channel *chan, const char *number, char *location, int maxloc, char *technology, int maxtech, char *suffix, char *options, unsigned int record, struct enum_context **argcontext) |
Lookup entry in ENUM. | |
int | ast_get_txt (struct ast_channel *chan, const char *number, char *txt, int maxtxt, char *suffix) |
Lookup DNS TXT record (used by app TXTCIDnum) |
DNS and ENUM functions.
Definition in file enum.h.
int ast_enum_init | ( | void | ) |
Definition at line 997 of file enum.c.
References private_enum_init().
Referenced by main().
{ return private_enum_init(0); }
int ast_enum_reload | ( | void | ) |
Definition at line 1002 of file enum.c.
References private_enum_init().
{ return private_enum_init(1); }
int ast_get_enum | ( | struct ast_channel * | chan, |
const char * | number, | ||
char * | location, | ||
int | maxloc, | ||
char * | technology, | ||
int | maxtech, | ||
char * | suffix, | ||
char * | options, | ||
unsigned int | record, | ||
struct enum_context ** | argcontext | ||
) |
Lookup entry in ENUM.
chan | Channel |
number | E164 number with or without the leading + |
location | Number returned (or SIP uri) |
maxloc | Max length |
technology | Technology (from url scheme in response) You can set it to get particular answer RR, if there are many techs in DNS response, example: "sip" If you need any record, then set it to "ALL" string |
maxtech | Max length |
suffix | Zone suffix (WARNING: No defaults here any more) |
options | Options 'c' - Count number of NAPTR RR number - Position of the requested RR in the answer list 'u' - Full URI return (does not strip URI scheme) 'i' - Infrastructure ENUM lookup 's' - ISN based lookup 'd' - Direct DNS query |
record | The position of required RR in the answer list |
argcontext | Argument for caching results into an enum_context pointer (NULL is used for not caching) |
1 | if found |
0 | if not found |
-1 | on hangup |
Definition at line 628 of file enum.c.
References ast_autoservice_start(), ast_autoservice_stop(), ast_calloc, ast_copy_string(), ast_debug, ast_free, ast_log(), ast_mutex_lock(), ast_mutex_unlock(), ast_search_dns(), ast_strlen_zero(), ast_tvdiff_ms(), ast_tvnow(), ast_verb, blr_ebl(), blr_txt(), cclen(), context, enum_context::count, enum_context::dst, enum_context::dstlen, enum_callback(), enumlock, ENUMLOOKUP_BLR_CC, ENUMLOOKUP_BLR_EBL, ENUMLOOKUP_BLR_TXT, ENUMLOOKUP_OPTIONS_COUNT, ENUMLOOKUP_OPTIONS_DIRECT, ENUMLOOKUP_OPTIONS_IENUM, ENUMLOOKUP_OPTIONS_ISN, errno, LOG_WARNING, enum_naptr_rr::naptr, enum_context::naptr_rrs, enum_context::naptr_rrs_count, enum_context::naptrinput, enum_context::options, naptr::order, enum_context::position, naptr::pref, enum_naptr_rr::result, enum_naptr_rr::sort_pos, enum_naptr_rr::tech, enum_context::tech, and enum_context::techlen.
Referenced by enum_query_read(), and function_enum().
{ struct enum_context *context; char tmp[512]; char domain[256]; char left[128]; char middle[128]; char naptrinput[128]; char apex[128] = ""; int ret = -1; /* for ISN rewrite */ char *p1 = NULL; char *p2 = NULL; char *p3 = NULL; int k = 0; int i = 0; int z = 0; int spaceleft = 0; struct timeval time_start, time_end; if (ast_strlen_zero(suffix)) { ast_log(LOG_WARNING, "ast_get_enum need a suffix parameter now.\n"); return -1; } ast_verb(2, "ast_get_enum(num='%s', tech='%s', suffix='%s', options='%s', record=%d\n", number, tech, suffix, options, record); /* We don't need that any more, that "n" preceding the number has been replaced by a flag in the options paramter. ast_copy_string(naptrinput, number, sizeof(naptrinput)); */ /* * The "number" parameter includes a leading '+' if it's a full E.164 number (and not ISN) * We need to preserve that as the regex inside NAPTRs expect the +. * * But for the domain generation, the '+' is a nuissance, so we get rid of it. */ ast_copy_string(naptrinput, number[0] == 'n' ? number + 1 : number, sizeof(naptrinput)); if (number[0] == '+') { number++; } if (!(context = ast_calloc(1, sizeof(*context)))) return -1; if((p3 = strchr(naptrinput, '*'))) { *p3='\0'; } context->naptrinput = naptrinput; /* The number */ context->dst = dst; /* Return string */ context->dstlen = dstlen; context->tech = tech; context->techlen = techlen; context->options = 0; context->position = record > 0 ? record : 1; context->count = 0; context->naptr_rrs = NULL; context->naptr_rrs_count = 0; /* * Process options: * * c Return count, not URI * i Use infrastructure ENUM * s Do ISN transformation * d Direct DNS query: no reversing. * */ if (options != NULL) { if (strchr(options,'s')) { context->options |= ENUMLOOKUP_OPTIONS_ISN; } else if (strchr(options,'i')) { context->options |= ENUMLOOKUP_OPTIONS_IENUM; } else if (strchr(options,'d')) { context->options |= ENUMLOOKUP_OPTIONS_DIRECT; } if (strchr(options,'c')) { context->options |= ENUMLOOKUP_OPTIONS_COUNT; } if (strchr(number,'*')) { context->options |= ENUMLOOKUP_OPTIONS_ISN; } } ast_verb(2, "ENUM options(%s): pos=%d, options='%d'\n", options, context->position, context->options); ast_debug(1, "ast_get_enum(): n='%s', tech='%s', suffix='%s', options='%d', record='%d'\n", number, tech, suffix, context->options, context->position); /* * This code does more than simple RFC3261 ENUM. All these rewriting * schemes have in common that they build the FQDN for the NAPTR lookup * by concatenating * - a number which needs be flipped and "."-seperated (left) * - some fixed string (middle) * - an Apex. (apex) * * The RFC3261 ENUM is: left=full number, middle="", apex=from args. * ISN: number = "middle*left", apex=from args * I-ENUM: EBL parameters build the split, can change apex * Direct: left="", middle=argument, apex=from args * */ /* default: the whole number will be flipped, no middle domain component */ ast_copy_string(left, number, sizeof(left)); middle[0] = '\0'; /* * I-ENUM can change the apex, thus we copy it */ ast_copy_string(apex, suffix, sizeof(apex)); /* ISN rewrite */ if ((context->options & ENUMLOOKUP_OPTIONS_ISN) && (p1 = strchr(number, '*'))) { *p1++ = '\0'; ast_copy_string(left, number, sizeof(left)); ast_copy_string(middle, p1, sizeof(middle) - 1); strcat(middle, "."); ast_verb(2, "ISN ENUM: left=%s, middle='%s'\n", left, middle); /* Direct DNS lookup rewrite */ } else if (context->options & ENUMLOOKUP_OPTIONS_DIRECT) { left[0] = 0; /* nothing to flip around */ ast_copy_string(middle, number, sizeof(middle) - 1); strcat(middle, "."); ast_verb(2, "DIRECT ENUM: middle='%s'\n", middle); /* Infrastructure ENUM rewrite */ } else if (context->options & ENUMLOOKUP_OPTIONS_IENUM) { int sdl = 0; char cc[8]; char sep[256], n_apex[256]; int cc_len = cclen(number); sdl = cc_len; ast_mutex_lock(&enumlock); ast_copy_string(sep, ienum_branchlabel, sizeof(sep)); /* default */ ast_mutex_unlock(&enumlock); switch (ebl_alg) { case ENUMLOOKUP_BLR_EBL: ast_copy_string(cc, number, cc_len); /* cclen() never returns more than 3 */ sdl = blr_ebl(cc, suffix, sep, sizeof(sep) - 1, n_apex, sizeof(n_apex) - 1); if (sdl >= 0) { ast_copy_string(apex, n_apex, sizeof(apex)); ast_verb(2, "EBL ENUM: sep=%s, apex='%s'\n", sep, n_apex); } else { sdl = cc_len; } break; case ENUMLOOKUP_BLR_TXT: ast_copy_string(cc, number, cc_len); /* cclen() never returns more than 3 */ sdl = blr_txt(cc, suffix); if (sdl < 0) sdl = cc_len; break; case ENUMLOOKUP_BLR_CC: /* BLR is at the country-code level */ default: sdl = cc_len; break; } if (sdl > strlen(number)) { /* Number too short for this sdl? */ ast_log(LOG_WARNING, "I-ENUM: subdomain location %d behind number %s\n", sdl, number); return 0; } ast_copy_string(left, number + sdl, sizeof(left)); ast_mutex_lock(&enumlock); ast_copy_string(middle, sep, sizeof(middle) - 1); strcat(middle, "."); ast_mutex_unlock(&enumlock); /* check the space we need for middle */ if ((sdl * 2 + strlen(middle) + 2) > sizeof(middle)) { ast_log(LOG_WARNING, "ast_get_enum: not enough space for I-ENUM rewrite.\n"); return -1; } p1 = middle + strlen(middle); for (p2 = (char *) number + sdl - 1; p2 >= number; p2--) { if (isdigit(*p2)) { *p1++ = *p2; *p1++ = '.'; } } *p1 = '\0'; ast_verb(2, "I-ENUM: cclen=%d, left=%s, middle='%s', apex='%s'\n", cc_len, left, middle, apex); } if (strlen(left) * 2 + 2 > sizeof(domain)) { ast_log(LOG_WARNING, "string to long in ast_get_enum\n"); return -1; } /* flip left into domain */ p1 = domain; for (p2 = left + strlen(left); p2 >= left; p2--) { if (isdigit(*p2)) { *p1++ = *p2; *p1++ = '.'; } } *p1 = '\0'; if (chan && ast_autoservice_start(chan) < 0) { ast_free(context); return -1; } spaceleft = sizeof(tmp) - 2; ast_copy_string(tmp, domain, spaceleft); spaceleft -= strlen(domain); if (*middle) { strncat(tmp, middle, spaceleft); spaceleft -= strlen(middle); } strncat(tmp,apex,spaceleft); time_start = ast_tvnow(); ret = ast_search_dns(context, tmp, C_IN, T_NAPTR, enum_callback); time_end = ast_tvnow(); ast_verb(2, "ast_get_enum() profiling: %s, %s, %d ms\n", (ret == 0) ? "OK" : "FAIL", tmp, ast_tvdiff_ms(time_end, time_start)); if (ret < 0) { ast_debug(1, "No such number found: %s (%s)\n", tmp, strerror(errno)); strcpy(dst, "0"); ret = 0; } if (context->naptr_rrs_count >= context->position && ! (context->options & ENUMLOOKUP_OPTIONS_COUNT)) { /* sort array by NAPTR order/preference */ for (k = 0; k < context->naptr_rrs_count; k++) { for (i = 0; i < context->naptr_rrs_count; i++) { /* use order first and then preference to compare */ if ((ntohs(context->naptr_rrs[k].naptr.order) < ntohs(context->naptr_rrs[i].naptr.order) && context->naptr_rrs[k].sort_pos > context->naptr_rrs[i].sort_pos) || (ntohs(context->naptr_rrs[k].naptr.order) > ntohs(context->naptr_rrs[i].naptr.order) && context->naptr_rrs[k].sort_pos < context->naptr_rrs[i].sort_pos)) { z = context->naptr_rrs[k].sort_pos; context->naptr_rrs[k].sort_pos = context->naptr_rrs[i].sort_pos; context->naptr_rrs[i].sort_pos = z; continue; } if (ntohs(context->naptr_rrs[k].naptr.order) == ntohs(context->naptr_rrs[i].naptr.order)) { if ((ntohs(context->naptr_rrs[k].naptr.pref) < ntohs(context->naptr_rrs[i].naptr.pref) && context->naptr_rrs[k].sort_pos > context->naptr_rrs[i].sort_pos) || (ntohs(context->naptr_rrs[k].naptr.pref) > ntohs(context->naptr_rrs[i].naptr.pref) && context->naptr_rrs[k].sort_pos < context->naptr_rrs[i].sort_pos)) { z = context->naptr_rrs[k].sort_pos; context->naptr_rrs[k].sort_pos = context->naptr_rrs[i].sort_pos; context->naptr_rrs[i].sort_pos = z; } } } } for (k = 0; k < context->naptr_rrs_count; k++) { if (context->naptr_rrs[k].sort_pos == context->position - 1) { ast_copy_string(context->dst, context->naptr_rrs[k].result, dstlen); ast_copy_string(context->tech, context->naptr_rrs[k].tech, techlen); break; } } } else if (!(context->options & ENUMLOOKUP_OPTIONS_COUNT)) { context->dst[0] = 0; } else if ((context->options & ENUMLOOKUP_OPTIONS_COUNT)) { snprintf(context->dst,context->dstlen,"%d",context->count); } if (chan) ret |= ast_autoservice_stop(chan); if (!argcontext) { for (k = 0; k < context->naptr_rrs_count; k++) { ast_free(context->naptr_rrs[k].result); ast_free(context->naptr_rrs[k].tech); } ast_free(context->naptr_rrs); ast_free(context); } else *argcontext = context; return ret; }
int ast_get_txt | ( | struct ast_channel * | chan, |
const char * | number, | ||
char * | txt, | ||
int | maxtxt, | ||
char * | suffix | ||
) |
Lookup DNS TXT record (used by app TXTCIDnum)
Really has nothing to do with enum, but anyway... Actually, there is now an internet-draft which describes how callerID should be stored in ENUM domains: draft-ietf-enum-cnam-04.txt The algorithm implemented here will thus be obsolete soon.
chan | Channel |
number | E164 number with or without the leading + |
txt | Text string (return value) |
maxtxt | Max length of "txt" |
suffix | Zone suffix |
Definition at line 918 of file enum.c.
References ast_autoservice_start(), ast_autoservice_stop(), ast_copy_string(), ast_debug, errno, and txt_context::txt.
Referenced by function_txtcidname().
{ struct txt_context context; char tmp[259 + 512]; int pos = strlen(number) - 1; int newpos = 0; int ret = -1; ast_debug(4, "ast_get_txt: Number = '%s', suffix = '%s'\n", number, suffix); if (chan && ast_autoservice_start(chan) < 0) { return -1; } if (pos > 128) { pos = 128; } while (pos >= 0) { if (isdigit(number[pos])) { tmp[newpos++] = number[pos]; tmp[newpos++] = '.'; } pos--; } ast_copy_string(&tmp[newpos], suffix, sizeof(tmp) - newpos); if (ret < 0) { ast_debug(2, "No such number found in ENUM: %s (%s)\n", tmp, strerror(errno)); ret = 0; } else { ast_copy_string(txt, context.txt, txtlen); } if (chan) { ret |= ast_autoservice_stop(chan); } return ret; }