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Diffstat (limited to 'lib/mlibc/options/posix/generic/lookup.cpp')
-rw-r--r--lib/mlibc/options/posix/generic/lookup.cpp512
1 files changed, 0 insertions, 512 deletions
diff --git a/lib/mlibc/options/posix/generic/lookup.cpp b/lib/mlibc/options/posix/generic/lookup.cpp
deleted file mode 100644
index f877fe5..0000000
--- a/lib/mlibc/options/posix/generic/lookup.cpp
+++ /dev/null
@@ -1,512 +0,0 @@
-#include <mlibc/lookup.hpp>
-#include <mlibc/resolv_conf.hpp>
-#include <mlibc/debug.hpp>
-#include <bits/ensure.h>
-
-#include <frg/string.hpp>
-#include <mlibc/allocator.hpp>
-#include <string.h>
-#include <errno.h>
-#include <arpa/inet.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <ctype.h>
-
-namespace mlibc {
-
-namespace {
- constexpr unsigned int RECORD_A = 1;
- constexpr unsigned int RECORD_CNAME = 5;
- constexpr unsigned int RECORD_PTR = 12;
-}
-
-static frg::string<MemoryAllocator> read_dns_name(char *buf, char *&it) {
- frg::string<MemoryAllocator> res{getAllocator()};
- while (true) {
- char code = *it++;
- if ((code & 0xC0) == 0xC0) {
- // pointer
- uint8_t offset = ((code & 0x3F) << 8) | *it++;
- auto offset_it = buf + offset;
- return res + read_dns_name(buf, offset_it);
- } else if (!(code & 0xC0)) {
- if (!code)
- break;
-
- for (int i = 0; i < code; i++)
- res += (*it++);
-
- if (*it)
- res += '.';
- } else {
- break;
- }
- }
-
- return res;
-}
-
-int lookup_name_dns(struct lookup_result &buf, const char *name,
- frg::string<MemoryAllocator> &canon_name) {
- frg::string<MemoryAllocator> request{getAllocator()};
-
- int num_q = 1;
- struct dns_header header;
- header.identification = htons(123);
- header.flags = htons(0x100);
- header.no_q = htons(num_q);
- header.no_ans = htons(0);
- header.no_auths = htons(0);
- header.no_additional = htons(0);
-
- request.resize(sizeof(header));
- memcpy(request.data(), &header, sizeof(header));
-
- const char *end = name;
- while (*end != '\0') {
- end = strchrnul(name, '.');
- size_t length = end - name;
- frg::string_view substring{name, length};
- name += length + 1;
- request += char(length);
- request += substring;
- }
-
- request += char(0);
- // set question type to fetch A records
- request += 0;
- request += 1;
- // set CLASS to IN
- request += 0;
- request += 1;
-
- struct sockaddr_in sin = {};
- sin.sin_family = AF_INET;
- // TODO(geert): we could probably make this use the service lookup
- // for dns
- sin.sin_port = htons(53);
-
- auto nameserver = get_nameserver();
- if (!inet_aton(nameserver ? nameserver->name.data() : "127.0.0.1", &sin.sin_addr)) {
- mlibc::infoLogger() << "lookup_name_dns(): inet_aton() failed!" << frg::endlog;
- return -EAI_SYSTEM;
- }
-
- int fd = socket(AF_INET, SOCK_DGRAM, 0);
- if (fd < 0) {
- mlibc::infoLogger() << "lookup_name_dns(): socket() failed" << frg::endlog;
- return -EAI_SYSTEM;
- }
-
- size_t sent = sendto(fd, request.data(), request.size(), 0,
- (struct sockaddr*)&sin, sizeof(sin));
- if (sent != request.size()) {
- mlibc::infoLogger() << "lookup_name_dns(): sendto() failed to send everything" << frg::endlog;
- return -EAI_SYSTEM;
- }
-
- char response[256];
- ssize_t rlen;
- int num_ans = 0;
- while ((rlen = recvfrom(fd, response, 256, 0, NULL, NULL)) >= 0) {
- if ((size_t)rlen < sizeof(struct dns_header))
- continue;
- auto response_header = reinterpret_cast<struct dns_header*>(response);
- if (response_header->identification != header.identification)
- return -EAI_FAIL;
-
- auto it = response + sizeof(struct dns_header);
- for (int i = 0; i < ntohs(response_header->no_q); i++) {
- auto dns_name = read_dns_name(response, it);
- (void) dns_name;
- it += 4;
- }
-
- for (int i = 0; i < ntohs(response_header->no_ans); i++) {
- struct dns_addr_buf buffer;
- auto dns_name = read_dns_name(response, it);
-
- uint16_t rr_type = (it[0] << 8) | it[1];
- uint16_t rr_class = (it[2] << 8) | it[3];
- uint16_t rr_length = (it[8] << 8) | it[9];
- it += 10;
- (void)rr_class;
-
- switch (rr_type) {
- case RECORD_A:
- memcpy(buffer.addr, it, rr_length);
- it += rr_length;
- buffer.family = AF_INET;
- buffer.name = std::move(dns_name);
- buf.buf.push(std::move(buffer));
- break;
- case RECORD_CNAME:
- canon_name = read_dns_name(response, it);
- buf.aliases.push(std::move(dns_name));
- break;
- default:
- mlibc::infoLogger() << "lookup_name_dns: unknown rr type "
- << rr_type << frg::endlog;
- break;
- }
- }
- num_ans += ntohs(response_header->no_ans);
-
- if (num_ans >= num_q)
- break;
- }
-
- close(fd);
- return buf.buf.size();
-}
-
-int lookup_addr_dns(frg::span<char> name, frg::array<uint8_t, 16> &addr, int family) {
- frg::string<MemoryAllocator> request{getAllocator()};
-
- int num_q = 1;
- struct dns_header header;
- header.identification = htons(123);
- header.flags = htons(0x100);
- header.no_q = htons(num_q);
- header.no_ans = htons(0);
- header.no_auths = htons(0);
- header.no_additional = htons(0);
-
- request.resize(sizeof(header));
- memcpy(request.data(), &header, sizeof(header));
-
- char addr_str[64];
- if(!inet_ntop(family, addr.data(), addr_str, sizeof(addr_str))) {
- switch(errno) {
- case EAFNOSUPPORT:
- return -EAI_FAMILY;
- case ENOSPC:
- return -EAI_OVERFLOW;
- default:
- return -EAI_FAIL;
- }
- }
- frg::string<MemoryAllocator> req_str{getAllocator(), addr_str};
- req_str += ".in-addr.arpa";
-
- frg::string_view req_view{req_str.data(), req_str.size()};
- size_t ptr = 0;
- do {
- size_t next = req_view.find_first('.', ptr);
- size_t length = next != (size_t)-1 ? next - ptr : req_view.size() - ptr;
- frg::string_view substring = req_view.sub_string(ptr, length);
- request += char(length);
- request += substring;
- ptr = next + 1;
- } while(ptr != 0);
-
- request += char(0);
- // set question type to fetch PTR records
- request += 0;
- request += 12;
- // set CLASS to IN
- request += 0;
- request += 1;
-
-
- struct sockaddr_in sin = {};
- sin.sin_family = AF_INET;
- // TODO(geert): we could probably make this use the service lookup
- // for dns
- sin.sin_port = htons(53);
-
- auto nameserver = get_nameserver();
- if (!inet_aton(nameserver ? nameserver->name.data() : "127.0.0.1", &sin.sin_addr)) {
- mlibc::infoLogger() << "lookup_name_dns(): inet_aton() failed!" << frg::endlog;
- return -EAI_SYSTEM;
- }
-
- int fd = socket(AF_INET, SOCK_DGRAM, 0);
- if (fd < 0) {
- mlibc::infoLogger() << "lookup_name_dns(): socket() failed" << frg::endlog;
- return -EAI_SYSTEM;
- }
-
- size_t sent = sendto(fd, request.data(), request.size(), 0,
- (struct sockaddr*)&sin, sizeof(sin));
- if (sent != request.size()) {
- mlibc::infoLogger() << "lookup_name_dns(): sendto() failed to send everything" << frg::endlog;
- return -EAI_SYSTEM;
- }
-
- char response[256];
- ssize_t rlen;
- int num_ans = 0;
- while ((rlen = recvfrom(fd, response, 256, 0, NULL, NULL)) >= 0) {
- if ((size_t)rlen < sizeof(struct dns_header))
- continue;
- auto response_header = reinterpret_cast<struct dns_header*>(response);
- if (response_header->identification != header.identification)
- return -EAI_FAIL;
-
- auto it = response + sizeof(struct dns_header);
- for (int i = 0; i < ntohs(response_header->no_q); i++) {
- auto dns_name = read_dns_name(response, it);
- (void) dns_name;
- it += 4;
- }
-
- for (int i = 0; i < ntohs(response_header->no_ans); i++) {
- struct dns_addr_buf buffer;
- auto dns_name = read_dns_name(response, it);
-
- uint16_t rr_type = (it[0] << 8) | it[1];
- uint16_t rr_class = (it[2] << 8) | it[3];
- uint16_t rr_length = (it[8] << 8) | it[9];
- it += 10;
- (void)rr_class;
- (void)rr_length;
-
- (void)dns_name;
-
- switch (rr_type) {
- case RECORD_PTR: {
- auto ptr_name = read_dns_name(response, it);
- if (ptr_name.size() >= name.size())
- return -EAI_OVERFLOW;
- std::copy(ptr_name.begin(), ptr_name.end(), name.data());
- name.data()[ptr_name.size()] = '\0';
- return 1;
- }
- default:
- mlibc::infoLogger() << "lookup_addr_dns: unknown rr type "
- << rr_type << frg::endlog;
- break;
- }
- num_ans += ntohs(response_header->no_ans);
-
- if (num_ans >= num_q)
- break;
- }
- }
-
- close(fd);
- return 0;
-}
-
-int lookup_name_hosts(struct lookup_result &buf, const char *name,
- frg::string<MemoryAllocator> &canon_name) {
- auto file = fopen("/etc/hosts", "r");
- if (!file) {
- switch (errno) {
- case ENOENT:
- case ENOTDIR:
- case EACCES:
- return -EAI_SERVICE;
- default:
- return -EAI_SYSTEM;
- }
- }
-
- char line[128];
- int name_length = strlen(name);
- while (fgets(line, 128, file)) {
- char *pos;
- // same way to deal with comments as in services.cpp
- if ((pos = strchr(line, '#'))) {
- *pos++ = '\n';
- *pos = '\0';
- }
-
- for(pos = line + 1; (pos = strstr(pos, name)) &&
- (!isspace(pos[-1]) || !isspace(pos[name_length])); pos++);
- if (!pos)
- continue;
-
- for (pos = line; !isspace(*pos); pos++);
- *pos = '\0';
-
- // TODO(geert): we assume ipv4 for now
- struct in_addr addr;
- if (!inet_aton(line, &addr))
- continue;
-
- pos++;
- for(; *pos && isspace(*pos); pos++);
- char *end;
- for(end = pos; *end && !isspace(*end); end++);
-
- struct dns_addr_buf buffer;
- memcpy(buffer.addr, &addr, 4);
- buffer.family = AF_INET;
- buffer.name = frg::string<MemoryAllocator>{pos,
- static_cast<size_t>(end - pos), getAllocator()};
- canon_name = buffer.name;
-
- buf.buf.push(std::move(buffer));
-
- pos = end;
- while (pos[1]) {
- for (; *pos && isspace(*pos); pos++);
- for (end = pos; *end && !isspace(*end); end++);
- auto name = frg::string<MemoryAllocator>{pos,
- static_cast<size_t>(end - pos), getAllocator()};
- buf.aliases.push(std::move(name));
- pos = end;
- }
- }
-
- fclose(file);
- return buf.buf.size();
-}
-
-int lookup_addr_hosts(frg::span<char> name, frg::array<uint8_t, 16> &addr, int family) {
- auto file = fopen("/etc/hosts", "r");
- if (!file) {
- switch (errno) {
- case ENOENT:
- case ENOTDIR:
- case EACCES:
- return -EAI_SERVICE;
- default:
- return -EAI_SYSTEM;
- }
- }
-
- // Buffer to hold ASCII version of address
- char addr_str[64];
- if(!inet_ntop(family, addr.data(), addr_str, sizeof(addr_str))) {
- switch(errno) {
- case EAFNOSUPPORT:
- return -EAI_FAMILY;
- case ENOSPC:
- return -EAI_OVERFLOW;
- default:
- return -EAI_FAIL;
- }
- }
- int addr_str_len = strlen(addr_str);
-
- char line[128];
- while (fgets(line, 128, file)) {
- char *pos;
- // same way to deal with comments as in services.cpp
- if ((pos = strchr(line, '#'))) {
- *pos++ = '\n';
- *pos = '\0';
- }
- if (strncmp(line, addr_str, addr_str_len))
- continue;
-
- for (pos = line + addr_str_len + 1; isspace(*pos); pos++);
- char *begin = pos;
- for (; !isspace(*pos); pos++);
- char *end = pos;
-
- size_t size = end - begin;
- if (size >= name.size())
- return -EAI_OVERFLOW;
- std::copy(begin, end, name.data());
- name.data()[size] = '\0';
- return 1;
- }
- return 0;
-}
-
-int lookup_name_null(struct lookup_result &buf, int flags, int family) {
- if (flags & AI_PASSIVE) {
- if (family != AF_INET6) {
- struct dns_addr_buf addr_buf;
- addr_buf.family = AF_INET;
-
- in_addr_t addr = INADDR_ANY;
- memcpy(&addr_buf.addr, &addr, 4);
-
- buf.buf.push_back(addr_buf);
- }
- if (family != AF_INET) {
- struct dns_addr_buf addr_buf;
- addr_buf.family = AF_INET6;
-
- struct in6_addr addr = IN6ADDR_ANY_INIT;
- memcpy(&addr_buf.addr, &addr, 16);
-
- buf.buf.push_back(addr_buf);
- }
- } else {
- if (family != AF_INET6) {
- struct dns_addr_buf addr_buf;
- addr_buf.family = AF_INET;
-
- in_addr_t addr = INADDR_LOOPBACK;
- memcpy(&addr_buf.addr, &addr, 4);
-
- buf.buf.push_back(addr_buf);
- }
- if (family != AF_INET) {
- struct dns_addr_buf addr_buf;
- addr_buf.family = AF_INET6;
-
- struct in6_addr addr = IN6ADDR_LOOPBACK_INIT;
- memcpy(&addr_buf.addr, &addr, 16);
-
- buf.buf.push_back(addr_buf);
- }
- }
- return buf.buf.size();
-}
-
-int lookup_name_ip(struct lookup_result &buf, const char *name, int family) {
- if (family == AF_INET) {
- in_addr_t addr = 0;
- int res = inet_pton(AF_INET, name, &addr);
-
- if (res <= 0)
- return -EAI_NONAME;
-
- struct dns_addr_buf addr_buf;
- addr_buf.family = AF_INET;
- memcpy(&addr_buf.addr, &addr, 4);
-
- buf.buf.push_back(addr_buf);
- return 1;
- }
-
- if (family == AF_INET6) {
- struct in6_addr addr{0};
- int res = inet_pton(AF_INET6, name, &addr);
-
- if (res <= 0)
- return -EAI_NONAME;
-
- struct dns_addr_buf addr_buf;
- addr_buf.family = AF_INET6;
- memcpy(&addr_buf.addr, &addr, 16);
-
- buf.buf.push_back(addr_buf);
- return 1;
- }
-
- // If no family was specified we try ipv4 and then ipv6.
- in_addr_t addr4 = 0;
- int res = inet_pton(AF_INET, name, &addr4);
-
- if (res > 0) {
- struct dns_addr_buf addr_buf;
- addr_buf.family = AF_INET;
- memcpy(&addr_buf.addr, &addr4, 4);
-
- buf.buf.push_back(addr_buf);
- return 1;
- }
-
- struct in6_addr addr6{0};
- res = inet_pton(AF_INET6, name, &addr6);
-
- if (res <= 0)
- return -EAI_NONAME;
-
- struct dns_addr_buf addr_buf;
- addr_buf.family = AF_INET6;
- memcpy(&addr_buf.addr, &addr6, 16);
-
- buf.buf.push_back(addr_buf);
- return 1;
-}
-
-} // namespace mlibc
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