X-Git-Url: http://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fgcrypt%2Frsagen.c;fp=src%2Fgcrypt%2Frsagen.c;h=d9f42b70ce9f55616dcb738b706cadb3f55babf1;hb=551cd19406a560d0d206bff5b4e9da064ec222b6;hp=0000000000000000000000000000000000000000;hpb=911c05f873ad967c40d04aa7347b1067fe62c055;p=tinc diff --git a/src/gcrypt/rsagen.c b/src/gcrypt/rsagen.c new file mode 100644 index 00000000..d9f42b70 --- /dev/null +++ b/src/gcrypt/rsagen.c @@ -0,0 +1,222 @@ +/* + rsagen.c -- RSA key generation and export + Copyright (C) 2008 Guus Sliepen + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + $Id$ +*/ + +#include "system.h" + +#include + +#include "rsagen.h" + +#if 0 +// Base64 encoding table + +static const char b64e[64] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + +// PEM encoding + +static bool pem_encode(FILE *fp, const char *header, uint8_t *buf, size_t size) { + bool decode = false; + char line[1024]; + uint32_t word = 0; + int shift = 0; + size_t i, j = 0; + + fprintf(fp, "-----BEGIN %s-----\n", header); + + for(i = 0; i < size; i += 3) { + if(i <= size - 3) { + word = buf[i] << 16 | buf[i + 1] << 8 | buf[i + 2]; + } else { + word = buf[i] << 16; + if(i == size - 2) + word |= buf[i + 1] << 8; + } + + line[j++] = b64e[(word >> 18) ]; + line[j++] = b64e[(word >> 12) & 0x3f]; + line[j++] = b64e[(word >> 6) & 0x3f]; + line[j++] = b64e[(word ) & 0x3f]; + + if(j >= 64) { + line[j++] = '\n'; + line[j] = 0; + fputs(line, fp); + j = 0; + } + } + + if(size % 3 > 0) { + if(size % 3 > 1) + line[j++] = '='; + line[j++] = '='; + } + + if(j) { + line[j++] = '\n'; + line[j] = 0; + fputs(line, fp); + } + + fprintf(fp, "-----END %s-----\n", header); + + return true; +} + + +// BER encoding functions + +static bool ber_write_id(uint8_t **p, size_t *buflen, int id) { + if(*buflen <= 0) + return false; + + if(id >= 0x1f) { + while(id) { + if(*buflen <= 0) + return false; + + (*buflen)--; + **p = id & 0x7f; + id >>= 7; + if(id) + **p |= 0x80; + (*p)++; + } + } else { + (*buflen)--; + *(*p)++ = id; + } + + return true; +} + +static bool ber_write_len(uint8_t **p, size_t *buflen, size_t len) { + do { + if(*buflen <= 0) + return false; + + (*buflen)--; + **p = len & 0x7f; + len >>= 7; + if(len) + **p |= 0x80; + (*p)++; + } while(len); + + return true; +} + +static bool ber_write_sequence(uint8_t **p, size_t *buflen, uint8_t *seqbuf, size_t seqlen) { + if(!ber_write_id(p, buflen, 0x10) || !ber_write_len(p, buflen, seqlen) || *buflen < seqlen) + return false; + + memcpy(*p, seqbuf, seqlen); + *p += seqlen; + *buflen -= seqlen; + + return true; +} + +static bool ber_write_mpi(uint8_t **p, size_t *buflen, gcry_mpi_t mpi) { + uint8_t tmpbuf[1024]; + size_t tmplen = sizeof tmpbuf; + gcry_error_t err; + + err = gcry_mpi_aprint(GCRYMPI_FMT_USG, &tmpbuf, &tmplen, mpi); + if(err) + return false; + + if(!ber_write_id(p, buflen, 0x02) || !ber_write_len(p, buflen, tmplen) || *buflen < tmplen) + return false; + + memcpy(*p, tmpbuf, tmplen); + *p += tmplen; + *buflen -= tmplen; + + return true; +} + +// Write PEM RSA keys + +bool rsa_write_pem_public_key(rsa_t *rsa, FILE *fp) { + uint8_t derbuf1[8096]; + uint8_t derbuf2[8096]; + uint8_t *derp1 = derbuf1; + uint8_t *derp2 = derbuf2; + size_t derlen1 = sizeof derbuf1; + size_t derlen2 = sizeof derbuf2; + + if(!ber_write_mpi(&derp1, &derlen1, &rsa->n) + || !ber_write_mpi(&derp1, &derlen1, &rsa->e) + || !ber_write_sequence(&derp2, &derlen2, derbuf1, derlen1)) { + logger(LOG_ERR, _("Error while encoding RSA public key")); + return false; + } + + if(!pem_encode(fp, "RSA PUBLIC KEY", derbuf2, derlen2)) { + logger(LOG_ERR, _("Unable to write RSA public key: %s"), strerror(errno)); + return false; + } + + return true; +} + +bool rsa_write_pem_private_key(rsa_t *rsa, FILE *fp) { + uint8_t derbuf1[8096]; + uint8_t derbuf2[8096]; + uint8_t *derp1 = derbuf1; + uint8_t *derp2 = derbuf2; + size_t derlen1 = sizeof derbuf1; + size_t derlen2 = sizeof derbuf2; + + if(!ber_write_mpi(&derp1, &derlen1, &bits) + || ber_write_mpi(&derp1, &derlen1, &rsa->n) // modulus + || ber_write_mpi(&derp1, &derlen1, &rsa->e) // public exponent + || ber_write_mpi(&derp1, &derlen1, &rsa->d) // private exponent + || ber_write_mpi(&derp1, &derlen1, &p) + || ber_write_mpi(&derp1, &derlen1, &q) + || ber_write_mpi(&derp1, &derlen1, &exp1) + || ber_write_mpi(&derp1, &derlen1, &exp2) + || ber_write_mpi(&derp1, &derlen1, &coeff)) + logger(LOG_ERR, _("Error while encoding RSA private key")); + return false; + } + + if(!pem_encode(fp, "RSA PRIVATE KEY", derbuf2, derlen2)) { + logger(LOG_ERR, _("Unable to write RSA private key: %s"), strerror(errno)); + return false; + } + + return true; +} +#endif + +bool rsa_write_pem_public_key(rsa_t *rsa, FILE *fp) { + return false; +} + +bool rsa_write_pem_private_key(rsa_t *rsa, FILE *fp) { + return false; +} + +bool rsa_generate(rsa_t *rsa, size_t bits, unsigned long exponent) { + fprintf(stderr, _("Generating RSA keys with libgcrypt not implemented yet\n")); + return false; +}