X-Git-Url: https://git.sommitrealweird.co.uk/onak.git/blobdiff_plain/d5ee45b742e49fa30cc8d0a5a69ee47c8c5b1eb5..89b73506f3cfe1c0238c3fb5c1af2e696a115f4d:/keyid.c diff --git a/keyid.c b/keyid.c index 6bb2e19..8cf32ba 100644 --- a/keyid.c +++ b/keyid.c @@ -4,12 +4,15 @@ * Jonathan McDowell * * Copyright 2002 Project Purple + * + * $Id: keyid.c,v 1.7 2003/06/04 20:57:09 noodles Exp $ */ #include #include "keyid.h" #include "keystructs.h" +#include "log.h" #include "md5.h" #include "sha.h" @@ -24,50 +27,55 @@ uint64_t get_keyid(struct openpgp_publickey *publickey) } /** - * get_packetid - Given a PGP packet returns the keyid. - * @packet: The packet to calculate the id for. + * get_fingerprint - Given a public key returns the fingerprint. + * @publickey: The key to calculate the id for. + * @fingerprint: The fingerprint (must be at least 20 bytes of space). + * @len: The length of the returned fingerprint. + * + * This function returns the fingerprint for a given public key. As Type 3 + * fingerprints are 16 bytes and Type 4 are 20 the len field indicates + * which we've returned. */ -uint64_t get_packetid(struct openpgp_packet *packet) +unsigned char *get_fingerprint(struct openpgp_packet *packet, + unsigned char *fingerprint, + size_t *len) { SHA1_CONTEXT sha_ctx; - uint64_t keyid = 0; - int offset = 0; - int i = 0; + MD5_CONTEXT md5_ctx; unsigned char c; unsigned char *buff = NULL; + size_t modlen, explen; - assert(packet != NULL); + assert(fingerprint != NULL); + assert(len != NULL); + + *len = 0; switch (packet->data[0]) { case 2: case 3: + md5_init(&md5_ctx); + /* - * For a type 2 or 3 key the keyid is the last 64 bits of the - * public modulus n, which is stored as an MPI from offset 8 - * onwards. - * - * We need to ensure it's an RSA key. + * MD5 the modulus and exponent. */ - if (packet->data[7] == 1) { - offset = (packet->data[8] << 8) + - packet->data[9]; - offset = ((offset + 7) / 8) + 2; + modlen = ((packet->data[8] << 8) + + packet->data[9] + 7) >> 3; + md5_write(&md5_ctx, &packet->data[10], modlen); + + explen = ((packet->data[10+modlen] << 8) + + packet->data[11+modlen] + 7) >> 3; + md5_write(&md5_ctx, &packet->data[12 + modlen], explen); + + md5_final(&md5_ctx); + buff = md5_read(&md5_ctx); + + *len = 16; + memcpy(fingerprint, buff, *len); - for (keyid = 0, i = 0; i < 8; i++) { - keyid <<= 8; - keyid += packet->data[offset++]; - } - } else { - fputs("Type 2 or 3 key, but not RSA.\n", stderr); - } break; + case 4: - /* - * For a type 4 key the keyid is the last 64 bits of the - * fingerprint, which is the 160 bit SHA-1 hash of the packet - * tag, 2 octet packet length and the public key packet - * including version field. - */ sha1_init(&sha_ctx); /* * TODO: Can this be 0x99? Are all public key packets old @@ -84,7 +92,58 @@ uint64_t get_packetid(struct openpgp_packet *packet) sha1_final(&sha_ctx); buff = sha1_read(&sha_ctx); - assert(buff != NULL); + *len = 20; + memcpy(fingerprint, buff, *len); + break; + default: + logthing(LOGTHING_ERROR, "Unknown key type: %d", + packet->data[0]); + } + + return fingerprint; +} + + +/** + * get_packetid - Given a PGP packet returns the keyid. + * @packet: The packet to calculate the id for. + */ +uint64_t get_packetid(struct openpgp_packet *packet) +{ + uint64_t keyid = 0; + int offset = 0; + int i = 0; + size_t length = 0; + unsigned char buff[20]; + + assert(packet != NULL); + + switch (packet->data[0]) { + case 2: + case 3: + /* + * For a type 2 or 3 key the keyid is the last 64 bits of the + * public modulus n, which is stored as an MPI from offset 8 + * onwards. + * + * We need to ensure it's an RSA key. + */ + if (packet->data[7] == 1) { + offset = (packet->data[8] << 8) + + packet->data[9]; + offset = ((offset + 7) / 8) + 2; + + for (keyid = 0, i = 0; i < 8; i++) { + keyid <<= 8; + keyid += packet->data[offset++]; + } + } else { + logthing(LOGTHING_ERROR, + "Type 2 or 3 key, but not RSA."); + } + break; + case 4: + get_fingerprint(packet, buff, &length); for (keyid = 0, i = 12; i < 20; i++) { keyid <<= 8; @@ -93,7 +152,7 @@ uint64_t get_packetid(struct openpgp_packet *packet) break; default: - fprintf(stderr, "Unknown key type: %d\n", + logthing(LOGTHING_ERROR, "Unknown key type: %d", packet->data[0]); }