X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=gnutls-helpers.c;h=6eae29e0aa3a32352c62212587a33118d5ca973f;hb=9c7796a6c4f3964c9255b3741fe92ed4ddd9a41d;hp=f5d37e602eb40da9aad86d93d4f1473b067a19cb;hpb=106d82cc8db97956d373f09e44dcdee661918c90;p=monkeysphere.git diff --git a/gnutls-helpers.c b/gnutls-helpers.c index f5d37e6..6eae29e 100644 --- a/gnutls-helpers.c +++ b/gnutls-helpers.c @@ -3,6 +3,14 @@ /* License: GPL v3 or later */ #include "gnutls-helpers.h" +/* for htonl() */ +#include + +/* for setlocale() */ +#include + +/* for isalnum() */ +#include int loglevel = 0; @@ -12,12 +20,31 @@ void err(const char* fmt, ...) { va_start(ap, fmt); vfprintf(stderr, fmt, ap); va_end(ap); + fflush(stderr); } void logfunc(int level, const char* string) { fprintf(stderr, "GnuTLS Logging (%d): %s\n", level, string); } +void init_keyid(gnutls_openpgp_keyid_t keyid) { + memset(keyid, 'x', sizeof(gnutls_openpgp_keyid_t)); +} + + + +void make_keyid_printable(printable_keyid out, gnutls_openpgp_keyid_t keyid) +{ + static const char hex[16] = "0123456789ABCDEF"; + unsigned int kix = 0, outix = 0; + + while (kix < sizeof(gnutls_openpgp_keyid_t)) { + out[outix] = hex[(keyid[kix] >> 4) & 0x0f]; + out[outix + 1] = hex[keyid[kix] & 0x0f]; + kix++; + outix += 2; + } +} int init_gnutls() { @@ -137,7 +164,7 @@ int set_datum_fd(gnutls_datum_t* d, int fd) { return 0; } -/* read the file indicated (by na1me) in the fname parameter. store +/* read the file indicated (by name) in the fname parameter. store its entire contents in a single datum. */ int set_datum_file(gnutls_datum_t* d, const char* fname) { struct stat sbuf; @@ -173,3 +200,165 @@ int set_datum_file(gnutls_datum_t* d, const char* fname) { fclose(file); return 0; } + +int write_datum_fd(int fd, const gnutls_datum_t* d) { + if (d->size != write(fd, d->data, d->size)) { + err("failed to write body of datum.\n"); + return -1; + } + return 0; +} + + +int write_datum_fd_with_length(int fd, const gnutls_datum_t* d) { + uint32_t len; + int looks_negative = (d->data[0] & 0x80); + unsigned char zero = 0; + + /* if the first bit is 1, then the datum will appear negative in the + MPI encoding style used by OpenSSH. In that case, we'll increase + the length by one, and dump out one more byte */ + + if (looks_negative) { + len = htonl(d->size + 1); + } else { + len = htonl(d->size); + } + if (write(fd, &len, sizeof(len)) != sizeof(len)) { + err("failed to write size of datum.\n"); + return -2; + } + if (looks_negative) { + if (write(fd, &zero, 1) != 1) { + err("failed to write padding byte for MPI.\n"); + return -2; + } + } + return write_datum_fd(fd, d); +} + +int write_data_fd_with_length(int fd, const gnutls_datum_t** d, unsigned int num) { + unsigned int i; + int ret; + + for (i = 0; i < num; i++) + if (ret = write_datum_fd_with_length(fd, d[i]), ret != 0) + return ret; + + return 0; +} + + +int datum_from_string(gnutls_datum_t* d, const char* str) { + d->size = strlen(str); + d->data = gnutls_realloc(d->data, d->size); + if (d->data == 0) + return ENOMEM; + memcpy(d->data, str, d->size); + return 0; +} + + +int create_writing_pipe(pid_t* pid, const char* path, char* const argv[]) { + int p[2]; + int ret; + + if (pid == NULL) { + err("bad pointer passed to create_writing_pipe()\n"); + return -1; + } + + if (ret = pipe(p), ret == -1) { + err("failed to create a pipe (error: %d \"%s\")\n", errno, strerror(errno)); + return -1; + } + + *pid = fork(); + if (*pid == -1) { + err("Failed to fork (error: %d \"%s\")\n", errno, strerror(errno)); + return -1; + } + if (*pid == 0) { /* this is the child */ + close(p[1]); /* close unused write end */ + + if (0 != dup2(p[0], 0)) { /* map the reading end into stdin */ + err("Failed to transfer reading file descriptor to stdin (error: %d \"%s\")\n", errno, strerror(errno)); + exit(1); + } + execv(path, argv); + err("exec %s failed (error: %d \"%s\")\n", path, errno, strerror(errno)); + /* close the open file descriptors */ + close(p[0]); + close(0); + + exit(1); + } else { /* this is the parent */ + close(p[0]); /* close unused read end */ + return p[1]; + } +} + +int validate_ssh_host_userid(const char* userid) { + char* oldlocale = setlocale(LC_ALL, "C"); + + /* choke if userid does not match the expected format + ("ssh://fully.qualified.domain.name") */ + if (strncmp("ssh://", userid, strlen("ssh://")) != 0) { + err("The user ID should start with ssh:// for a host key\n"); + goto fail; + } + /* so that isalnum will work properly */ + userid += strlen("ssh://"); + while (0 != (*userid)) { + if (!isalnum(*userid)) { + err("label did not start with a letter or a digit! (%s)\n", userid); + goto fail; + } + userid++; + while (isalnum(*userid) || ('-' == (*userid))) + userid++; + if (('.' == (*userid)) || (0 == (*userid))) { /* clean end of label: + check last char + isalnum */ + if (!isalnum(*(userid - 1))) { + err("label did not end with a letter or a digit!\n"); + goto fail; + } + if ('.' == (*userid)) /* advance to the start of the next label */ + userid++; + } else { + err("invalid character in domain name: %c\n", *userid); + goto fail; + } + } + /* ensure that the last character is valid: */ + if (!isalnum(*(userid - 1))) { + err("hostname did not end with a letter or a digit!\n"); + goto fail; + } + /* FIXME: fqdn's can be unicode now, thanks to RFC 3490 -- how do we + make sure that we've got an OK string? */ + + return 0; + + fail: + setlocale(LC_ALL, oldlocale); + return 1; +} + +/* http://tools.ietf.org/html/rfc4880#section-5.5.2 */ +size_t get_openpgp_mpi_size(gnutls_datum_t* d) { + return 2 + d->size; +} + +int write_openpgp_mpi_to_fd(int fd, gnutls_datum_t* d) { + uint16_t x; + + x = d->size * 8; + x = htons(x); + + write(fd, &x, sizeof(x)); + write(fd, d->data, d->size); + + return 0; +}